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Sample records for hydrochemical conditions controlling

  1. Hydrochemical Atlas of the Arctic Ocean (NODC Accession 0044630)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The present Hydrochemical Atlas of the Arctic Ocean is a description of hydrochemical conditions in the Arctic Ocean on the basis of a greater body of hydrochemical...

  2. Expertize of hydrochemical investigation Know-how for deep underground

    International Nuclear Information System (INIS)

    Iwatsuki, Teruki; Mizuno, Takashi; Amano, Yuki; Kunimaru, Takanori; Semba, Takeshi

    2012-03-01

    This report summarizes technical basis and the Know-how on hydrochemical investigations for deep underground as a part of METI project 'Development of Information Synthesis and Interpretation System (ISIS)'. We describe the procedures and methods of hydrochemical investigation in following stages; 1) initial analysis of previous information, 2) planning of borehole investigation, 3) borehole investigation at field, and 4) construct the 'hydrochemical model' representing hydrochemical condition and the evolution process. The contents of this report are inputted to 'Expert system' developed by METI project and are available on WEB system (internet). (author)

  3. Scenario development of long-term evolution for deep hydrochemical conditions in Horonobe area, Hokkaido, Japan

    International Nuclear Information System (INIS)

    Iwatsuki, Teruki; Ishii, Eiichi; Niizato, Tadafumi

    2009-01-01

    A methodology to estimate long-term hydrochemical evolution of deep underground is indispensable for the safe geological isolation of high-level radioactive waste (HLW). This study demonstrates the methodology by illustrating scenarios of past geological events, processes, and their interrelationships with present-day hydrochemical conditions. Besides, we infer long-term variations of groundwater chemistry at Horonobe, Hokkaido, Japan. The region is underlain mainly by Neogene to Quaternary marine sedimentary rocks, (the Wakkanai Formation (Fm) and the overlying Koetoi Fm: siliceous and diatomaceous mudstones). During various events in the geological past, such as deposition, compaction, uplift, and denudation, and the more recent Neotectonic activities in this area, highly permeable hydrogeological structures formed at depths not over than 400 m below ground level in the Wakkanai Fm. The hydrogeological system can be subdivided into three hydrogeological sub-systems: (1) overlying, relatively low permeability Koetoi Fm., (2) highly permeable, upper Wakkanai Fm at depths less than 400 m and (3) relatively low permeability Wakkanai Fm, at depths greater than 400 m. The present-day hydrochemical conditions in each sub-system have been influenced by hydrogeological properties and hydraulic conditions over a long period. In subsystems 1 and 2, recharging with meteoric water flushed connate seawater during uplifting and denudation during the last 1 Ma. In contrast, fossil seawater with one-third to one-half the salinity of present-day seawater has been preserved in subsystem 3. The relatively low permeability sequence in sub-system 3 was formed by the compaction of diatomaceous mudstone during subsidence prior to 1.0 Ma. After that, changes of climatic conditions and geographical features would not have influenced groundwater flow. The groundwater chemistry evolved from seawater during long-term geochemical diagenesis in a relatively closed system. The long

  4. Hydrochemical characterization of groundwater aquifer using ...

    African Journals Online (AJOL)

    Hydrochemical data analysis revealed four sources of solutes. The processes responsible for their enrichment include: chemical weathering, leaching of the overlying sediments, domestic activities, climatic condition and the flow pattern of the aquifer. The factors have contributed to the changes of the groundwater chemistry ...

  5. Hydrochemical aspects of the Aue pit flooding

    International Nuclear Information System (INIS)

    Meyer, J.; Jenk, U.; Schuppan, W.; Knappik, R.

    1998-01-01

    WISMUT is conducting controlled flooding of underground mines at the Schlema-Alberoda and Poehla sites. Flooding of the Poehla mine lasted from January 1992 through September 1995. Flooding at the Niederschlema-Alberoda site began in July 1990 and will continue to approximately 2002. In mid-1998 the flood level had reached the - 420 m level which is about 1,400 m above the lowest mine level. Only ground waters with low mineral and pollutant content are used for flooding purposes. Typically, the flooding process results in elevated levels of mineral salts and of uranium, radium, arsenic, iron, and manganese in flooding waters. However, the mobilised part of these contaminants represents only a small fraction of potential concentrations contained in the surrounding rock. Geochemical and hydrochemical conditions at both mines are characterised by the presence of carbonate buffers and by neutral pH and intermediate to low Eh. Decrease due to oxidation of sulphides in the long term is unlikely. Environmentally relevant metals in flooding waters may be dissolved, colloidal, or suspended solids with uranium present as uranyl carbonate complexes. Intensity of mobilisation is primarily a function of kinetic processes. Post flooding conditions at the Poehla subsite exhibit specific hydrochemical phenomena such as extremely reduced SO 4 concentrations and an increase in Ra concentrations over time. Continued flood monitoring will provide the basis for more in-depth interpretation and prognosis of contaminant mobilisation. Current investigations focus on technically feasible in situ control of mine flooding at the Schlema-Alberoda site to reduce contaminant mobilisation. At both sites water treatment plants are either on stream or under construction. (orig.)

  6. Hydrochemical Characteristics and Evolution Laws of Drinking Groundwater in Pengyang County, Ningxia, Northwest China

    Directory of Open Access Journals (Sweden)

    Li Peiyue

    2011-01-01

    Full Text Available The purpose of the paper is to identify the chemical characteristics of drinking groundwater and its distribution patterns in Pengyang County and to discover the hydrochemical evolution laws of groundwater. The temporal and spatial variation of groundwater hydrochemical characteristics and evolution laws were comprehensively and systematically studied based on the understanding of the geological, hydrogeological, meteorological and hydrological conditions. Many analytical methods such as descriptive statistics, geostatistical analysis, ionic ratio coefficient method and correlation analysis were adopted based on the underground water quality analysis data. Study results showed that variation coefficients of chemical parameters of pore water in unconsolidated rocks were relatively high which indicated that water chemical compositions are vulnerable to topography, meteorology, hydrology and human activities. TDS variation was in accordance with the changes in Ca2+, Mg2+ and SO42- concentration. Hydrochemical type varied from HCO3•SO4-Na•Ca•Mg type and HCO3•SO4-Ca•Mg type at the upper reaches towards gradually to HCO3-Na type at the lower reaches. Ionic ratio coefficient analysis showed that the hydrodynamic conditions of the pore water in loose rocks were better than that of pore-fissure water in clastic rocks and groundwater was non-marine deposited water. Its formation effects include the weathering leaching effects of the formation containing rock salt, water-rock interaction and cation exchange reaction. Hydrochemical characteristics were mainly controlled by geological and hydrogeological conditions. Correlation analysis showed that the dissolution of rock salt and sodium sulfate salt as well as calcite precipitation occurred in pore water and in pore-crack water in clastic rocks the dissolution of albite, K-feldspar and the precipitation of dolomite were also important effects.

  7. Hydrochemical evolution and groundwater flow processes in the Galilee and Eromanga basins, Great Artesian Basin, Australia: a multivariate statistical approach.

    Science.gov (United States)

    Moya, Claudio E; Raiber, Matthias; Taulis, Mauricio; Cox, Malcolm E

    2015-03-01

    The Galilee and Eromanga basins are sub-basins of the Great Artesian Basin (GAB). In this study, a multivariate statistical approach (hierarchical cluster analysis, principal component analysis and factor analysis) is carried out to identify hydrochemical patterns and assess the processes that control hydrochemical evolution within key aquifers of the GAB in these basins. The results of the hydrochemical assessment are integrated into a 3D geological model (previously developed) to support the analysis of spatial patterns of hydrochemistry, and to identify the hydrochemical and hydrological processes that control hydrochemical variability. In this area of the GAB, the hydrochemical evolution of groundwater is dominated by evapotranspiration near the recharge area resulting in a dominance of the Na-Cl water types. This is shown conceptually using two selected cross-sections which represent discrete groundwater flow paths from the recharge areas to the deeper parts of the basins. With increasing distance from the recharge area, a shift towards a dominance of carbonate (e.g. Na-HCO3 water type) has been observed. The assessment of hydrochemical changes along groundwater flow paths highlights how aquifers are separated in some areas, and how mixing between groundwater from different aquifers occurs elsewhere controlled by geological structures, including between GAB aquifers and coal bearing strata of the Galilee Basin. The results of this study suggest that distinct hydrochemical differences can be observed within the previously defined Early Cretaceous-Jurassic aquifer sequence of the GAB. A revision of the two previously recognised hydrochemical sequences is being proposed, resulting in three hydrochemical sequences based on systematic differences in hydrochemistry, salinity and dominant hydrochemical processes. The integrated approach presented in this study which combines different complementary multivariate statistical techniques with a detailed assessment of the

  8. Tomographic, hydrochemical and isotopic investigations of the ...

    Indian Academy of Sciences (India)

    An electrical imaging tomography survey was carried out to identify the lateral and vertical salinity distribution in the oasis shallow aquifers of the Nefzaoua region located in southwestern Tunisia. In addition, hydrochemical and isotopic data were examined to determine the main factors and mechanisms controlling the ...

  9. Design considerations for the acquisition of hydrochemical data from deep boreholes

    International Nuclear Information System (INIS)

    McCartney, R.; Ledingham, P.

    1998-01-01

    Deep (>300 m) subsurface hydrochemical data are important components of geological investigations of potential radioactive waste disposal sites. These data can be interpreted to yield information that supports conceptual hydrogeological models, constrains palaeohydrogeological evolution and characterises subsurface hydrochemical conditions of a site. The most important sources of these data are the analyses of groundwater samples collected during extraction tests performed in boreholes either during drilling or after drilling has been completed. To maximise the information obtained from their interpretation, the quality and quantity of hydrochemical data obtained should be such that they are representative of the compositions of the in-situ groundwaters, the in-situ location of all groundwaters should be known, and the key trends in groundwater compositions should be identifiable from the data set. The design of deep borehole-based hydrochemical data acquisition programmes to meet such objectives is a complex task. It is useful to simplify the design process by focusing attention on those activities and parameters that are most likely to affect the quality and quantity of hydrochemical data obtained from the final implemented design. In this paper we examine those design parameters associated with drilling (cutting method, drilling fluids, flushing method, drill string and bottom hole assembly), fluid extraction testing (timing, test tools, fluid extraction method), sampling (sampling locations, timing of sampling, numbers of samples, sample collection methods), and sample analysis (analytical precision and accuracy, location and timing of analyses) activities. For each parameter we discuss the design options available , and identify those with features that are most likely to be beneficial or detrimental to the quality and quantity of hydrochemical data. Preferred design options have been identified where possible. However, each investigation will have a number of

  10. Experimental evidence on formation of imminent and short-term hydrochemical precursors for earthquakes

    International Nuclear Information System (INIS)

    Du Jianguo; Amita, Kazuhiro; Ohsawa, Shinji; Zhang Youlian; Kang Chunli; Yamada, Makoto

    2010-01-01

    The formation of imminent hydrochemical precursors of earthquakes is investigated by the simulation for water-rock reaction in a brittle aquifer. Sixty-one soaking experiments were carried out with granodiorite and trachyandesite grains of different sizes and three chemically-distinct waters for 6 to 168 h. The experimental data demonstrate that water-rock reaction can result in both measurable increases and decreases of ion concentrations in short times and that the extents of hydrochemical variations are controlled by the grain size, dissolution and secondary mineral precipitation, as well as the chemistry of the rock and groundwater. The results indicate that water-rock reactions in brittle aquifers and aquitards may be an important genetic mechanism of hydrochemical seismic precursors when the aquifers and aquitards are fractured in response to tectonic stress.

  11. Site characterization and validation - hydrochemical investigations. Stage 3

    International Nuclear Information System (INIS)

    Laaksoharju, M.

    1990-02-01

    The objective for the Stage 3 hydrochemical investigations was to classify groundwater and to determine the different flow paths within the investigated SCV-site by using water analyses from the C and D boreholes. The water was divided into three classes shallow (A), mixed (B) and deep groundwater (C) based on Cl and HCO 3 concentration. The local geohydrological situation in the SCV-site can be divided into a disturbed situation and an undisturbed situation. Opening of the boreholes and smapling causes a disturbance of hydrochemical conditions. Three water types were found in the important water conductors, the GB and the GH zones. Shallow water (A-type) is flowing downwards while deep groundwater (C-type) is flowing upwards driven by the pumping of the mine. Where the two water types meet a zone of approximately 30 m thickness with mixed (B-type) water is formed. The flow situation is revealed by the geohydrological measurements. At undisturbed conditions shallow water (A-type) is flowing down in the investigated zones. The B and C water types are then found at a deeper level than during disturbed conditions. A regional model can be constructed based on the described chemical and geohydrological investigations. Shallow water from the top and deep groundwater from below are drawn towards the mine by the pumping. Where these waters meet mixed water is formed. (orig./HP)

  12. Hydrochemical characterizatin and water quality monitoring by means of specific computer systems

    International Nuclear Information System (INIS)

    Alvarez, E.; Fagundo, J.R.

    1998-01-01

    The computer systems SAPHIQ and SIMUCIN, for the hydrochemical data process with the aim to characterize and control the water quality, as well as to simulate the water-rock interaction process are presented. (author)

  13. Hydrochemical investigations in crystalline bedrock in relation to existing hydraulic conditions: experiences from the SKB test-sites in Sweden

    International Nuclear Information System (INIS)

    Smellie, J.; Larsson, N.Aa.; Wikberg, P.; Carlsson, L.

    1985-11-01

    This report represents the compilation, discussion and interpretation of hydrochemical and hydraulic data resulting from the SKB test-site investigations carried out over a period of three years (1982-84). By systematically applying hydrological and geological considerations to each sampled horizon, it has been possible to differentiate between those groundwaters which are reasonably representative for the depth sampled, from those which have been subject to contamination from different sources. Groundwaters which are here considered representative are defined as those which show no evidence of mixing with other water sources, whether from drilling water, younger, near-surface water, or other deeper groundwaters. As a consequence, only a few sampled horizons can be considered with serious hydrochemical attention. The lack of representative groundwater samples, whilst often due to technical problems or sampling from non-conductive sections of the boreholes, also illustrate the extremely complex geometry of the premeable fracture systems in crystalline bedrock, and thus the difficulty of establishing the nature and depth relation of the groundwater tapped. Although the main findings of this study have revealed gross inadequacies in the hydrochemical programme, valuable experience has nevertheless been gained. Consequently, some of the improvements recommended in Section 7 of this report have been already implemented resulting in higher sampling standards and thus water samples which are much more representative for the hydrogeological environment under investigation. (author)

  14. The investigation of the kinetics of hydrochemical oxidation of metal sulphides with the aim of determination of the optimal conditions for the selective extraction of molybdenum from ores

    Directory of Open Access Journals (Sweden)

    Lutsik V.

    2005-01-01

    Full Text Available The kinetics of the oxidation of molybdenyte, pyrite and sphalerite in solutions of nitric acid, hydrogen peroxide, and sodium hypochlorite was studied by the rotating disk method. The influence of the molar concentration of reagent, pH of solution, temperature, disk rotation frequency, and duration of measurements on the specific rate of hydrochemical oxidation of sulpfides was determined. The kinetic models allowing to calculate the dissolution rate of sulphides when these parameters change simultaneously were obtained. The conditions of kinetically and diffusion-controlled processes were detected. The details of mechanism of the studied processes were revealed. The nature of intermediate solid products, the reasons and the conditions of their formation as well as the character of their influence on the kinetics of dissolution processes were determined. The probable schemes of interactions corresponding to the observable kinetic dependences were offered. The conditions of the effective and selective molybdenum leaching directly from ore without its concentration were found.

  15. Prospecting effect of the combined gamma-ray survey in the hydrochemical reconnaissance

    International Nuclear Information System (INIS)

    Hu Zheng'an.

    1991-01-01

    Gamma-ray survey is characterized by economies, rapidness, portability and continuous measurement in uranium reconnaissance. Combined gamma-ray survey can be conducted in hydrochemical reconnaissance with less investment and faster results, and prospects for detailed prospecting and exposing can be directly found by the survey. The arrangements in the field operation is suited to hydrochemical reconnaissance. By working for one time two sets of data with different characteristics could be obtained. In data interpretation and application, both data can be mutually complementary. It is a blank area for the non-water section in hydrochemical reconnaissance in which gamma-ray survey can be supplemented. Gamma-ray survey can provide data for the interpretation of hydrochemical anomalies and the size and concentration of hydrochemical anomalies are the basis for the inference of the mineralization at depth. The statistical results confirm that as compared with the conventional gamma-ray survey (at 1:10000 scale), the discovery rate of anomalies from the combined gamma-ray survey (at 1: 25000 scale) may reach 60%. It is thus that the data from the combined gamma-ray survey can be applied by lowering one grade in measurement accuracy which can meet the demand for accuracy

  16. Hydrochemical synthesis Northern Switzerland: tertiary- and Malm-aquifers

    International Nuclear Information System (INIS)

    Schmassmann, H.; Kullin, M.; Wexsteen, P.

    1990-05-01

    This Tertiary-Malm synthesis represents the first part of an overall hydrochemical synthesis of deep groundwaters in Northern Switzerland and adjacent areas. The investigation is mainly based on data from Nagra deep boreholes, from Nagra regional programme as well as from external sources. The first part provides a hydrogeological overview including a brief description of the aquifer rocks. A compilation of all existing hydraulic potential data is given and discussed for Northern Switzerland, Bodensee area and western Swabian Alb. In the Molasse Basin, hydrochemical and isotope analyses allowed a distinction of three main water types positioned one upon another: calcium-magnesium-bicarbonate groundwaters, sodium-bicarbonate and sodium-chloride deep groundwaters. Hydrochemical and isotopegeochemical details of these three water types comprise the major part of this report. Unlike the other two water types, the calcium-magnesium-bicarbonate groundwaters also include shallow waters with considerable tritium activities, indicating a mean residence time of less than 35 years. The spacial distribution of these three water types are demonstrated and different secular flow models in the Tertiary-Malm Aquifer group are discussed. (author) figs., tabs., 194 refs

  17. [Temporal-spatial Variation and Source Identification of Hydro-chemical Characteristics in Shima River Catchment, Dongguan City].

    Science.gov (United States)

    Gao, Lei; Chen, Jian-yao; Wang, Jiang; Ke, Zhi-ting; Zhu, Ai-ping; Xu, Kai

    2015-05-01

    Shima River catchment is of strategic importance to urban water supply in Dongjiang portable water source area. To investigate the hydro-chemical characteristics of Shima River, 39 river water samples were collected in February, June and November, 2012 to analyze the major ions (K+, Na+, Ca2+, Mg2+, Cl-, SO4(2-) , HCO3-) and nutritive salts (PO4(3-), NO3- and NH4+) and to discuss the temporal-spatial variation and controlling factors of hydro-chemical composition, relative sources identification of varied ions was performed as well. The results showed that the hydro-chemical composition exhibited significant differences in different periods. The average concentration of total dissolved solid ( TDS) and nutritive salts in different investigated periods followed the decreasing order of November > February > June. The dominant anion of Shima River was HCO3-, and Na+ + K+ were the major cations in February and November which were changed to Ca2+ in June, the hydro-chemical types were determined as HCO(3-)-Na+ and HCO(3-)- Ca2+ in dry (February and November) and rainy (June) seasons, respectively. Spatial variations of concentration of nutritive salts were mainly affected by the discharges of N- and P-containing waste water resulted from human activities. The ratio between N and P of water sample (R7) was 18.4:1 which boosted the "crazy growth" of phytoplankton and led to severe eutrophication. According to Gibbs distribution of water samples, dissolution of hydatogenic rocks was the primary factor to control the major cations of river water in dry season, however, the hydro-chemical composition was significantly affected by the combination of hydatogenic and carbonate rocks in rainy season. The deposition of sea-salts contributed less to chemical substances in river. Correlation analysis revealed that K+, Na+, Mg2+, Cl- and SO4(2-) were partly derived from the application of fertilizer and the discharge of industrial effluent; Waste water of poultry feeding and

  18. Tomographic, hydrochemical and isotopic investigations of the ...

    Indian Academy of Sciences (India)

    2Department of Geography, Laboratory of Radio-Analyses and Environment, BP 1168, ... addition, hydrochemical and isotopic data were examined to determine the main factors and mecha- .... Previous hydrogeologic studies identified lentic-.

  19. Scale dependence of the episodic hydrochemical response of nested catchments at Plynlimon

    Directory of Open Access Journals (Sweden)

    H. J. Foster

    1997-01-01

    Full Text Available Previous monitoring of the surface water chemistry of the forested catchments at Plynlimon has concentrated on weekly measurements. Hence, peak values and details of the rapid changes in chemistry occurring during events tend to be missed, particularly for smaller catchments. Knowledge of the detailed hydrochemical response is necessary to predict effects on stream ecology and to quantify processes occurring within the catchment. This information is vital if the likely impacts of changes in landuse and pollutant input on episodic hydrochemical variations are to be modelled. A summary of daily and three-hourly chemistry for the River Severn headwaters at Plynlimon, central Wales is presented. Data are from the summer and autumn of 1995 and the winter and summer of 1996. The effects of antecedent conditions, soiltype, landuse and groundwater and tributary inflow on stream episodic hydrochemical response are discussed for a range of spatial scales, including first, second and third order streams. Detailed information on the chemical changes due to a discrete groundwater inflow into the bed of one stream shows that, during episodes, its influence on stream chemistry is overridden by that of event water. A comparison of drainage ditch chemistry with main stream chemistry during storm events is used to consider the importance of tributary inflow at these times. The contrast in results between sites is assessed, to evaluate the effects of clearfelling and soil type on stream event chemistry.

  20. Spatio-temporal variation analysis of hydrochemical characteristics in the Luanhe River Basin, China.

    Science.gov (United States)

    Xie, Ying; Li, Xuyong; Wang, Huiliang; Li, Wenzan

    2013-01-01

    The analysis of river pollution and assessment of spatial and temporal variation in hydrochemistry are essential to river water pollution control in the context of rapid economic growth and growing pollution threats in China. In this study, we focused on hydrochemical characteristics of the Luanhe River Basin (China) and evaluation of 12 hydrochemical variables obtained from 32 monitoring stations during 2001-2010. In each study year, the streams were monitored in the three hydrological periods (April, August, and October) to observe differences in the impacts of agricultural activity and rainfall pattern. Multivariate statistical methods were applied to the data set, and the river water hydrochemical characteristics were assessed using the water quality identification index (WQIIM). The results showed that parameters had variable contribution to water quality status in different months except for ammonia nitrogen (NH4-N) and total nitrogen (TN), which were the most important parameters in contributing to water quality variations for all three periods. Results of WQIIM revealed that 18 sites were classified as 'meeting standard' while the other 14 sites were classified as 'not meeting standard', with most of the seriously polluted sites located in urban area, mainly due to discharge of wastewater from domestic and industrial sources. Sites with low pollution level were located primarily in smaller tributaries, whereas sites of medium and high pollution levels were in the main river channel and the larger tributaries. Our findings provide valuable information and guidance for water pollution control and water resource management in the Luanhe River Basin.

  1. Groundwater Chemistry Regulated by Hydrochemical Processes and Geological Structures: A Case Study in Tongchuan, China

    Directory of Open Access Journals (Sweden)

    Xinyan Li

    2018-03-01

    Full Text Available Knowledge of hydrochemical processes in groundwater helps to identify the relationship between geochemical processes and groundwater quality as well as to understand the hydrochemical evaluation of groundwater, which is important for the sustainable management of groundwater resources. This study aims to identify the chemical characteristics of groundwater in the area of Tongchuan City, China. A total of 58 groundwater samples were collected. A hierarchical cluster analysis divided samples into three clusters and six sub-clusters (cluster 1a, 1b, 2a, 2b, 3a, 3b according to hydrochemical facies. Graphical plots of multiple ionic ratios, saturation indices, and ion exchange indices were employed to examine hydrochemical processes that result in different hydrochemical facies of each cluster. Results show the predominance of carbonate and silicate weathering in cluster 1, silicate weathering in cluster 2, and carbonate weathering in cluster 3. Ionic exchange is a ubiquitous process among all clusters. The distribution of clusters is related to the regional geology, which may result in different hydrochemical processes. Two stratigraphic sections identify the differences in hydrochemical processes resulting from complex stratum structures and varied aquifer media. Cluster 2a shows an interesting difference in water chemistry along the groundwater flow path. Further study by oxygen and hydrogen isotope indicated that mixing between Quaternary and the Permian aquifers resulting from faulting is the main reason for the distinctive characteristic of cluster 2a.

  2. Hydraulic and hydrochemical characteristics of the phreatic ...

    African Journals Online (AJOL)

    Hydraulic and hydrochemical characteristics of the phreatic basement aquifers in parts of southwestern Nigeria. OA Idowu, O Martins, AM Gbadebo. Abstract. No Abstract. Journal of Mining and Geology Vol. 43 (1) 2007: pp. 71-78. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD ...

  3. Assessment of groundwater–surface water interaction using long-term hydrochemical data and isotope hydrology: Headwaters of the Condamine River, Southeast Queensland, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Jorge L., E-mail: jlmarti@ig.com.br [Queensland University of Technology, Brisbane (Australia); Raiber, Matthias [CSIRO Land and Water Flagship, Brisbane (Australia); Cox, Malcolm E. [Queensland University of Technology, Brisbane (Australia)

    2015-12-01

    A spatial analysis of hydrochemical data of groundwater and surface water was undertaken to identify groundwater-surface water connectivity in the headwaters of the Condamine River catchment, Southeast Queensland, Australia. An assessment of long-term hydrochemical and water level data supplemented by stable- and radioisotope measurements following a prolonged dry period dominated by baseflow, helped in determining patterns of interaction in different tributaries of the upper Condamine catchment. A conceptual hydrological model representing the major hydrochemical processes and their implications for stream-aquifer connectivity was developed and tested using multiple lines of evidence. The results of a multivariate statistical analysis highlight that there are two main regions with distinct hydrochemical facies (salinity, alkalinity, and predominant ions) in surface water. Geomorphology, geology, anthropogenic and climate influence were identified as the most relevant controlling factors of the spatial variability in water quality. Stable isotope data confirmed a clear evaporation trend in almost all surface water samples during baseflow conditions. Two water types can be identified and separated by the degree of evaporation and the proximity of one group to the local meteoric water line. The results confirm the discharge of groundwater from aquifers recharged by rainfall and located upstream of the surface water sampling sites. Overall, {sup 222}Rn data show a trend of increased activity in surface water towards the upstream portions of these tributaries, validating the use of this tracer to estimate groundwater input to the local creeks. The proportion of groundwater contribution to stream flow calculated by {sup 222}Rn and chloride mass balance is in agreement, and ranges between 20–70% in tributaries in the northern areas, and between 8–50% in the upper reaches of the main river channel. This study shows the efficacy of an integrated approach combining long

  4. Assessment of groundwater–surface water interaction using long-term hydrochemical data and isotope hydrology: Headwaters of the Condamine River, Southeast Queensland, Australia

    International Nuclear Information System (INIS)

    Martinez, Jorge L.; Raiber, Matthias; Cox, Malcolm E.

    2015-01-01

    A spatial analysis of hydrochemical data of groundwater and surface water was undertaken to identify groundwater-surface water connectivity in the headwaters of the Condamine River catchment, Southeast Queensland, Australia. An assessment of long-term hydrochemical and water level data supplemented by stable- and radioisotope measurements following a prolonged dry period dominated by baseflow, helped in determining patterns of interaction in different tributaries of the upper Condamine catchment. A conceptual hydrological model representing the major hydrochemical processes and their implications for stream-aquifer connectivity was developed and tested using multiple lines of evidence. The results of a multivariate statistical analysis highlight that there are two main regions with distinct hydrochemical facies (salinity, alkalinity, and predominant ions) in surface water. Geomorphology, geology, anthropogenic and climate influence were identified as the most relevant controlling factors of the spatial variability in water quality. Stable isotope data confirmed a clear evaporation trend in almost all surface water samples during baseflow conditions. Two water types can be identified and separated by the degree of evaporation and the proximity of one group to the local meteoric water line. The results confirm the discharge of groundwater from aquifers recharged by rainfall and located upstream of the surface water sampling sites. Overall, 222 Rn data show a trend of increased activity in surface water towards the upstream portions of these tributaries, validating the use of this tracer to estimate groundwater input to the local creeks. The proportion of groundwater contribution to stream flow calculated by 222 Rn and chloride mass balance is in agreement, and ranges between 20–70% in tributaries in the northern areas, and between 8–50% in the upper reaches of the main river channel. This study shows the efficacy of an integrated approach combining long

  5. Hydrochemical and isotopic tracing of mixing dynamics and water quality evolution under pumping conditions in the mine shaft of the abandoned Frances Colliery, Scotland

    International Nuclear Information System (INIS)

    Elliot, Trevor; Younger, Paul L.

    2007-01-01

    Since 1995, when pumps were withdrawn from deep mines in East Fife (Scotland), mine waters have been rebounding throughout the coalfield. Recently, it has become necessary to pump and treat these waters to prevent their uncontrolled emergence at the surface. However, even relatively shallow pumping to surface treatment lagoons of the initially chemically-stratified mine water from a shaft in the coastal Frances Colliery during two dynamic step-drawdown tests to establish the hydraulic characteristics of the system resulted in rapid breakdown of the stratification within 24 h and a poor pumped water quality with high dissolved Fe loading. Further, data are presented here of hydrochemical and isotopic sampling of the extended pump testing lasting up to several weeks. The use in particular of the environmental isotopes δ 18 O, δ 2 H, δ 34 S, 3 H, 13 C and 14 C alongside hydrochemical and hydraulic pump test data allowed characterisation of the Frances system dynamics, mixing patterns and water quality sources feeding into this mineshaft under continuously pumped conditions. The pumped water quality reflects three significant components of mixing: shallow freshwater, seawater, and leakage from the surface treatment lagoons. In spite of the early impact of recirculating lagoon waters on the hydrochemistries, the highest Fe loadings in the longer-term pumped waters are identified with a mixed freshwater-seawater component affected by pyrite oxidation/melanterite dissolution in the subsurface system

  6. Groundwater hydrochemical assessment of the crystalline aquifer of ...

    African Journals Online (AJOL)

    The data sets obtained from the laboratory were subjected to descriptive statistics and correlation matrix to establish their relationship, including water quality index were calculated. The hydrochemical results revealed high mean concentrations of conductivity followed by total hardness, total dissolved solids, alkalinity, ...

  7. Hydrochemical characteristics and spatial analysis of groundwater quality in parts of Bundelkhand Massif, India

    Science.gov (United States)

    Ali, Syed Ahmad; Ali, Umair

    2018-03-01

    The tribulations of water quality have become more serious than the quantity, as the environmental evils are getting more severe day by day in different parts of the world. Large number of components like soil, geology, sewage disposal, effluents and other environmental conditions in which the water tends to reside or move and interact with ground and biological characteristics, greatly persuade the groundwater quality. Therefore, hydrochemical study has been carried out graphically and spatially in GIS environment in part of Bundelkhand Massif. The hydrochemical study exposes the water quality by measuring the concentration of parameters and comparing them with the drinking water and irrigation standards. Groundwater samples have been collected and analysed for physiochemical characteristics in order to understand the hydrochemistry of the water. The results revealed that ground water is alkaline in nature and total hardness observed in all samples falls under moderately hard to very hard category. At some places higher concentration of Cl- could be dangerous from health point of view. Major hydrochemical facies were identified using Piper Trilinear diagram and Durov diagrams, etc. Analysis of different determinations such as sodium adsorption ratio, residual sodium carbonate and per cent sodium revealed that most of the samples are unsuitable for irrigation. It was also observed that the quality of groundwater was not suitable for drinking purpose in industrial and irrigation area. In the area, few sampling sites showed unsuitability because of influences of urban and industrial waste discharge, aquifer material mineralogy, other anthropogenic activities and increased human interventions.

  8. Thermodynamic and hydrochemical controls on CH4 in a coal seam gas and overlying alluvial aquifer: new insights into CH4 origins

    OpenAIRE

    Owen, D. Des. R.; Shouakar-Stash, O.; Morgenstern, U.; Aravena, R.

    2016-01-01

    Using a comprehensive data set (dissolved CH4, ?13C-CH4, ?2H-CH4, ?13C-DIC, ?37Cl, ?2H-H2O, ?18O-H2O, Na, K, Ca, Mg, HCO3, Cl, Br, SO4, NO3 and DO), in combination with a novel application of isometric log ratios, this study describes hydrochemical and thermodynamic controls on dissolved CH4 from a coal seam gas reservoir and an alluvial aquifer in the Condamine catchment, eastern Surat/north-western Clarence-Moreton basins, Australia. ?13C-CH4 data in the gas reservoir (?58? to ?49?) and sha...

  9. Hydrochemical simulation of a mountain basin under hydrological variability

    Science.gov (United States)

    Montserrat, S.; Trewhela, T. A.; Navarro, L.; Navarrete, A.; Lagos Zuniga, M. A.; Garcia, A.; Caraballo, M.; Niño, Y.; McPhee, J. P.

    2016-12-01

    Water quality and the comprehension of hydrochemical phenomena in natural basins should be of complete relevance under hydrological uncertainties. The importance of identifying the main variables that are controlling a natural system and finding a way to predict their behavior under variable scenarios is mandatory to preserve these natural basins. This work presents an interdisciplinary model for the Yerba Loca watershed, a natural reserve basin in the Chilean central Andes. Based on different data sets, provided by public and private campaigns, a natural hydrochemical regime was identified. Yerba Loca is a natural reserve, characterized by the presence of several glaciers and wide sediment deposits crossed by a small low-slope creek in the upper part of the basin that leads to a high-slope narrow channel with less sediment depositions. Most relevant is the geological context around the glaciers, considering that most of them cover hydrothermal zones rich in both sulfides and sulfates, a situation commonly found in the Andes due to volcanic activity. Low pH (around 3), calcium-sulfate water with high concentrations of Iron, Copper and Zinc are found in the upper part of the basin in summer. These values can be attributed to the glaciers melting down and draining of the mentioned country rocks, which provide most of the creek flow in the upper basin. The latter clearly contrasts with the creek outlet, located 18 km downstream, showing near to neutral pH values and lower concentrations of the elements already mentioned. The scope of the present research is to account for the sources of the different hydrological inlets (e.g., rainfall, snow and/or glacier melting) that, depending on their location, may interact with a variety of reactive minerals and generate acid rock drainage (ARD). The inlet water is modeled along the creek using the softwares HEC-RAS and PHREEQC coupled, in order to characterize the water quality and to detect preferred sedimentation sections

  10. Groundwater Hydrochemical Zoning in Inland Plains and its Genetic Mechanisms

    Directory of Open Access Journals (Sweden)

    Liting Xing

    2018-06-01

    Full Text Available Pore water in inland plain areas, generally having poor water quality, contain complex hydrochemical properties. In order to examine groundwater chemical composition formation characteristics, groundwater in the Jiyang area of Lubei Plain was studied using stratified monitoring of drilling, analysis of water level and water quality, isotope analysis, ion ratio coefficient and isothermal adsorption experiments, hydrochemical characteristics, and analysis of variations in different shallow depths. Results show that: (1 Numerous hydrochemistry types are present in the diving. Along with the direction of groundwater flow, total dissolved solids (TDS of diving in the study area generally increases and the hydrochemical type changes from the HCO3 type to the HCO3·SO4 type, Cl·HCO3 type and the Cl·SO4 type. (2 Shallow brackish water and freshwater in the horizontal direction are alternately distributed, and shallow brackish water is distributed in the area between old channels, showing sporadic spots or bands, whose hydrochemistry type is predominantly Cl·SO4-Na·Mg·Ca. (3 Affected by the sedimentary environment, hydrodynamic conditions and other factors; diving, middle brackish water and deep freshwater are vertically deposited in the study area. The dynamics of middle brackish water quality are stable due to the sedimentary environment and clay deposits. The hydrochemistry types of middle brackish water are mainly Cl·SO4-Mg·Na and SO4·Cl-Na·Mg, while the deep confined water is dominated by HCO3. (4 The optimal adsorption isotherms of Na+, Ca2+ and Mg2+ in groundwater from clay, with a thickness raging from 6–112 m, conformed to the Henry equation and the Langmuir equation. The retardation of Na+, Ca2+ and Mg2+ in groundwater differed with differing depths of the clay deposit. The trend of change in retardation strength correlates strongly with the TDS of groundwater. Groundwater in the inland plain area is affected by complicated

  11. Hydrochemical and isotopic study of the Botucatu aquifer ground waters in Sao Paulo State

    International Nuclear Information System (INIS)

    Silva, R.B.G. da.

    1983-01-01

    The process controlling chemical composition of ground water,its origin and apparent age as well as, the natural flow rate of the water in Botucatu aquifer in state of Sao Paulo, Brazil, have been investigated using hydrochemical and environmental isotopic ( 18 O, 2 H, 13 C, 14 C) Technics. The main recharge process is assumed to be the infiltration of rain water in the aquifer outcrop area. The progressive confining conditions with the increasing depth of the top of the aquifer layer makes the ground water temperature slowly greater. The recent magnesium and sodium bicarbonated waters changes first to sodium bicarbonated and then to sodium chloride-sulfated waters which are oldest found out in the research area(around 30.000 years ago). The mean Darcy permeability estimated on basis of 14 C and hydraulic gradient data is 2.6x10 -5 m/s. 9 maps (author) [pt

  12. Hydrochemical analysis of groundwater using a tree-based model

    Science.gov (United States)

    Litaor, M. Iggy; Brielmann, H.; Reichmann, O.; Shenker, M.

    2010-06-01

    SummaryHydrochemical indices are commonly used to ascertain aquifer characteristics, salinity problems, anthropogenic inputs and resource management, among others. This study was conducted to test the applicability of a binary decision tree model to aquifer evaluation using hydrochemical indices as input. The main advantage of the tree-based model compared to other commonly used statistical procedures such as cluster and factor analyses is the ability to classify groundwater samples with assigned probability and the reduction of a large data set into a few significant variables without creating new factors. We tested the model using data sets collected from headwater springs of the Jordan River, Israel. The model evaluation consisted of several levels of complexity, from simple separation between the calcium-magnesium-bicarbonate water type of karstic aquifers to the more challenging separation of calcium-sodium-bicarbonate water type flowing through perched and regional basaltic aquifers. In all cases, the model assigned measures for goodness of fit in the form of misclassification errors and singled out the most significant variable in the analysis. The model proceeded through a sequence of partitions providing insight into different possible pathways and changing lithology. The model results were extremely useful in constraining the interpretation of geological heterogeneity and constructing a conceptual flow model for a given aquifer. The tree model clearly identified the hydrochemical indices that were excluded from the analysis, thus providing information that can lead to a decrease in the number of routinely analyzed variables and a significant reduction in laboratory cost.

  13. Hydrochemical Characteristics and Multivariate Statistical Analysis of Natural Water System: A Case Study in Kangding County, Southwestern China

    Directory of Open Access Journals (Sweden)

    Yunhui Zhang

    2018-01-01

    Full Text Available The utilization for water resource has been of great concern to human life. To assess the natural water system in Kangding County, the integrated methods of hydrochemical analysis, multivariate statistics and geochemical modelling were conducted on surface water, groundwater, and thermal water samples. Surface water and groundwater were dominated by Ca-HCO3 type, while thermal water belonged to Ca-HCO3 and Na-Cl-SO4 types. The analyzing results concluded the driving factors that affect hydrochemical components. Following the results of the combined assessments, hydrochemical process was controlled by the dissolution of carbonate and silicate minerals with slight influence from anthropogenic activity. The mixing model of groundwater and thermal water was calculated using silica-enthalpy method, yielding cold-water fraction of 0.56–0.79 and an estimated reservoir temperature of 130–199 °C, respectively. δD and δ18O isotopes suggested that surface water, groundwater and thermal springs were of meteoric origin. Thermal water should have deep circulation through the Xianshuihe fault zone, while groundwater flows through secondary fractures where it recharges with thermal water. Those analytical results were used to construct a hydrological conceptual model, providing a better understanding of the natural water system in Kangding County.

  14. Subsurface probe and hydrochemical analysis for the purpose of ...

    African Journals Online (AJOL)

    analysis for the purpose of siting waste landfill. The landfill design made provision for secured containment of the segregated waste and associated leachate from man and industrial activities. The waste types that are disposed of in the landfill are mainly domestic and non-hazardous industrial wastes. The hydrochemical ...

  15. Hydrochemical Regions of the Glacial Aquifer System, Northern United States, and Their Environmental and Water-Quality Characteristics

    Science.gov (United States)

    Arnold, Terri L.; Warner, Kelly L.; Groschen, George E.; Caldwell, James P.; Kalkhoff, Stephen J.

    2008-01-01

    characteristics of the clusters. The result of the Maximum Likelihood Classification is a map showing five hydrochemical regions of the glacial aquifer system. Statistical analysis of ion concentrations (calcium, chloride, fluoride, magnesium, sodium, potassium, sulfate, and bicarbonate) in samples collected from wells completed in the glacial aquifer system illustrates that variations in water quality can be explained, in part, by related environmental characteristics that control the movement of ground water through the aquifer system. A comparison of median concentrations of chemical constituents in ground water among the five hydrochemical regions indicates that ground water in the Midwestern Agricultural Region, the Urban-Influenced Region, and the Western Agriculture and Grassland Region has the highest concentrations of major and minor ions, whereas ground water in the Northern and Great Lakes Forested Region and the Mountain and Coastal Forested Region has the lowest concentrations of these ions. Median concentrations of barium, arsenic, lithium, boron, strontium, and nitrite plus nitrate as nitrogen also are significantly different among the hydrochemical regions.

  16. Hydrochemical zonation of the western part of Göksu Delta aquifer system, Southern Turkey

    Science.gov (United States)

    Dokuz, U. E.; Çelik, M.; Arslan, Ş.; Engin, H.

    2012-04-01

    In general, coastal areas are preferred places for human settlement, especially at places where infrastructure routes benefit from rivers, streets, or harbours. As a result, these areas usually suffer from rising population and endure increasingly high demand on natural resources like water. Göksu Delta, located in southern Turkey, is one of the important wetland areas of Turkey at the Mediterranean coast. It is divided into two parts by Göksu River. The western part of the delta, which is the subject matter of this study, hosts fertile agricultural fields, touristic places and a Special Environmental Protection Area. These properties of the region lead to a water-dependent ecosystem where groundwater has widely been used for agricultural and domestic purposes. When the exploitation of groundwater peaked in the middle of 1990s, the groundwater levels dropped and seawater intruded. General Directorate of State Hydraulic Works tried to stop seawater intrusion by building irrigation channels connected to Göksu River and banned drilling of new wells for groundwater exploitation, although it is hard to control the drilling of wells without official permit. Geological studies show that the delta is composed of terrestrial sediments including clay to coarse sand deposited during Quaternary. The heterogeneous sediments of Göksu Delta cause hydrogeological features of the aquifer systems to be heterogeneous and anisotropic. Hydrogeological investigations, therefore, indicate mainly two different aquifers, shallow and deep, separated by an aquitard. The shallow aquifer is under unconfined to confined conditions from north to south while the deep aquifer is under confined conditions. This study focuses on hydrogeochemical zonation in terms of hydrochemical processes that affect the Göksu Delta aquifer systems. For this purpose, hydrogeochemical and isotopic studies are conducted to understand the salinisation and softening processes of groundwater. The physicochemical

  17. Hydrochemical modelling of water quality in terms of emerging micropollutants in Mpumalanga, Gauteng and North West Provinces

    Science.gov (United States)

    Wanda, Elijah M. M.; Mamba, Bhekie B.; Msagati, Titus A. M.

    2017-08-01

    Emerging micropollutants (EMPs) are ubiquitous in aquatic systems and are associated with a wide range of eco-toxicological effects worldwide. There remains a lack of scientific understanding of the major underlying hydrochemical factors behind variations in concentration heterogeneities of EMPs in time and space. This study was therefore conducted to determine major hydrochemical processes controlling water quality and the occurrence of EMPs mainly, carbamazepine (CBZ), tonalide (AHTN), galaxolide (HHCB), caffeine (CAF), technical 4-nonylphenol (NP) and bisphenol A (BPA) in water from Mpumalanga, Gauteng and North West Provinces in South Africa. Grab water samples were collected bi-monthly between June 2014 and April 2016 from 44 water sources using standard sampling procedures. BPA, NP, CAF, HHCB, AHTN, CBZ were extracted, cleaned and enriched using autotrace-SPE at neutral pH and analyzed using GC × GC-TOFMS. Kruskal Wallis-test was used to test for temporal variations in occurrence of the analytes. The Geochemist's Workbench® Release 11 software, Surfer Golden Graphics for surface mapping, PHREEQC software and bivariate ion plots were used determine the major hydrogeochemical processes. The mean concentrations of EMPs varied from 3.48 μg/L for CAF to 421.53 μg/L for HHCB. Although the Kruskal Wallis test revealed no any statistically significant temporal variations in concentrations of the analytes in water samples at 95% confidence level, their occurrence and distribution vary spatially with BPA being the most widely distributed EMP and was present in 62% of the sampled sites. Municipal waste water inputs, agricultural pollution, ion-exchange reactions, carbonate and silicate weathering were the major processes controlling water quality in the study area. This study may assist water resource managers to ably address and manage water pollution resulting from a number of natural and anthropogenic hydrochemical processes in the study area.

  18. Colloidal stability of CeO2 nanoparticles coated with either natural organic matter or organic polymers under various hydrochemical conditions

    Science.gov (United States)

    Dippon, Urs; Pabst, Silke; Klitzke, Sondra

    2016-04-01

    The worldwide marked for engineered nanoparticles (ENPs) is growing and concerns on the environmental fate- and toxicity of ENPs are rising. Understanding the transport of ENPs within and between environmental compartments such as surface water and groundwater is crucial for exposition modeling, risk assessment and ultimately the protection of drinking water resources. The transport of ENPs is strongly influenced by the surface properties and aggregation behavior of the particles, which is strongly controlled by synthetic and natural organic coatings. Both, surface properties and aggregation characteristics are also key properties for the industrial application of ENPs, which leads to the development and commercialization of an increasing number of surface-functionalized ENPs. These include metals and oxides such as Cerium dioxide (CeO2) with various organic coatings. Therefore, we investigate CeO2 ENPs with different surface coatings such as weakly anionic polyvinyl alcohol (PVA) or strongly anionic poly acrylic acid (PAA) with respect to their colloidal stability in aqueous matrix under various hydrochemical conditions (pH, ionic strength) and their transport behavior in sand filter columns. Furthermore, we investigate the interaction of naturally occurring organic matter (NOM) with CeO2 ENPs and its effect on surface charge (zeta potential), colloidal stability and transport. While uncoated CeO2 ENPs aggregate at pH > 4 in aqueous matrix, our results show that PAA and PVA surface coatings as well as NOM sorbed to CeO2-NP surfaces can stabilize CeO2 ENPs under neutral and alkaline pH conditions in 1 mM KCl solution. Under slightly acidic conditions, differences between the three particle types were observed. PVA can stabilize particle suspensions in presence of 1 mM KCl at pH > 4.3, PAA at pH >4.0 and NOM at >3.2. While the presence of KCl did not influence particle size of NOM-CeO2 ENPs, CaCl2 at >2 mM lead to aggregation. Further results on the influence of KCl

  19. A hydrochemical data base for the Hanford Site, Washington

    International Nuclear Information System (INIS)

    Early, T.O.; Mudd, R.D.; Spice, G.D.; Starr, D.L.

    1985-02-01

    This data package contains a complete listing of the Site Hydrochemical Data Base for water samples associated with the Basalt Waste Isolation Project (BWIP). In addition to the detailed chemical analyses are a summary description of the data base format, detailed descriptions of verification procedures used to check data entries, and detailed descriptions of validation procedures used to evaluate data quality

  20. Groundwater quality and hydrochemical properties of Al-Ula Region, Saudi Arabia.

    Science.gov (United States)

    Toumi, Naji; Hussein, Belal H M; Rafrafi, Sarra; El Kassas, Neama

    2015-03-01

    Groundwater quality monitoring is one of the most important aspects in groundwater studies in arid environments particularly in developing countries, like Saudi Arabia, due to the fast population growth and the expansion of irrigated agriculture and industrial uses. Groundwater samples have been collected from eight locations in Al-Ula in Saudi Arabia during June 2012 and January 2013 in order to investigate the hydrochemical characteristics and the groundwater quality and to understand the sources of dissolved ions. Physicochemical parameters of groundwater such as electrical conductivity, pH, total dissolved solid, and major cations and anions were determined. Chloride was found to be the dominant anion followed by HCO(-) 3 and SO4 (2-). Groundwater of the study area is characterized by the dominance of alkaline earths (Ca(2+) + Mg(2+)) over alkali metals (Na(+) + K(+)). The analytical results show that the groundwater is generally moderately hard and slightly alkaline in nature. The binary relationships of the major ions reveal that water quality of the Al-Ula region is mainly controlled by rock weathering, evaporation, and ion exchange reactions. Piper diagram was constructed to identify hydrochemical facies, and it was found that majority of the samples belong to Ca-Cl and mixed Ca-Mg-Cl facies. Chemical indices like chloro-alkali indices, sodium adsorption ratio, percentage of sodium, residual sodium carbonate, and permeability index were calculated. Also, the results show that the chemical composition of groundwater sources of Al-Ula is strongly influenced by lithology of country rocks rather than anthropogenic activities.

  1. Water hydrochemical of the Punta Espinillo fissured aquifer, Montevideo-Uruguay

    International Nuclear Information System (INIS)

    Montano, J.; Peel, E.; Sienra, M.; Gianotti, V.; Lacues, X. . E mail: montanox@movinet.com.uy

    2004-01-01

    In the westernmost part of the Department of Montevideo an intensive agronomic activity is developed based on irrigation systems. There, the majority of the vegetables and fruits consumed in Montevideo city are produced. The studied area consists in approximately 1500 ha. divided into orchards of 5 ha or less. Former studies show that salinization risk is due to the proximity of de La Plata river and / or the draw - downs in static levels because of over exploitation. The aquifer type is fractured and shows flows from 2 m3/h to 20 m3/h. The aim of this work is to perform a preliminary hydrochemical characterization of the Punta Espinillo fractured aquifer system and to determine human use and irrigation aptitudes. The results show that the groundwater is sodi c bi carbonated and it varies from hard to very hard. Moreover, from the correlation studies between hydrochemical parameters it is observed that Cl- and SO42- ions are responsible for the high salinity. It is also observed that exist important restrictions for human and irrigation use [es

  2. Uranium as a possible criterion for the hydro-chemical alteration of betafite

    Science.gov (United States)

    Hosseinpour Khanmiri, Mohammad; Yanson, Svetlana Yu.; Fomin, Edward V.; Titov, Anatoly V.; Grebeniuk, Andrey V.; Polekhovsky, Yury S.; Bogdanov, Roman V.

    2018-01-01

    Hydro-chemical processes significantly alter the original composition of metamict minerals. In the work presented here, an attempt was made to reconstruct the chemical composition of betafite in the earlier stages of its geological history. The time scale is determined by the leaching rate of the isotope 238U, a process that takes its course in line with first-order kinetics, or something close to it. The leaching rate constant of this uranium isotope was assessed. Based on available data in the literature, the hydro-chemical behavior of various atoms in group A of betafite was analyzed. The chemical composition of the mineral was calculated taking into account the total charge of the cations that the betafite had at the time it was formed, or possibly the last time it was completely reformed as a result of diverse endogenic processes.

  3. Uranium as a possible criterion for the hydro-chemical alteration of betafite

    Science.gov (United States)

    Hosseinpour Khanmiri, Mohammad; Yanson, Svetlana Yu.; Fomin, Edward V.; Titov, Anatoly V.; Grebeniuk, Andrey V.; Polekhovsky, Yury S.; Bogdanov, Roman V.

    2018-06-01

    Hydro-chemical processes significantly alter the original composition of metamict minerals. In the work presented here, an attempt was made to reconstruct the chemical composition of betafite in the earlier stages of its geological history. The time scale is determined by the leaching rate of the isotope 238U, a process that takes its course in line with first-order kinetics, or something close to it. The leaching rate constant of this uranium isotope was assessed. Based on available data in the literature, the hydro-chemical behavior of various atoms in group A of betafite was analyzed. The chemical composition of the mineral was calculated taking into account the total charge of the cations that the betafite had at the time it was formed, or possibly the last time it was completely reformed as a result of diverse endogenic processes.

  4. Geophysical and hydro-chemical investigation of the area around a ...

    African Journals Online (AJOL)

    From the 2-D resistivity structures, contaminant plumes characterized by relatively low resistivity values (< 150 ohm-m) were identified down to depth of about 40 m in some places. Hydro-chemical results showed that the total acidity and concentration of Na+ Cl- and heavy metals (Cd, Cu, Fe, Hg and Pb) in wells closest to ...

  5. Hydrochemical characteristics of aquifers near Sutherland in the Western Karoo, South Africa

    CSIR Research Space (South Africa)

    Adams, S

    2001-01-15

    Full Text Available management. Descriptive statistics, correlation matrices and factor analysis, together with stable isotope data were used to gain an understanding of the hydrochemical processes of the groundwaters in the fractured rocks around Sutherland in the Western Karoo...

  6. Evolutionary analysis of groundwater flow: Application of multivariate statistical analysis to hydrochemical data in the Densu Basin, Ghana

    Science.gov (United States)

    Yidana, Sandow Mark; Bawoyobie, Patrick; Sakyi, Patrick; Fynn, Obed Fiifi

    2018-02-01

    An evolutionary trend has been postulated through the analysis of hydrochemical data of a crystalline rock aquifer system in the Densu Basin, Southern Ghana. Hydrochemcial data from 63 groundwater samples, taken from two main groundwater outlets (Boreholes and hand dug wells) were used to postulate an evolutionary theory for the basin. Sequential factor and hierarchical cluster analysis were used to disintegrate the data into three factors and five clusters (spatial associations). These were used to characterize the controls on groundwater hydrochemistry and its evolution in the terrain. The dissolution of soluble salts and cation exchange processes are the dominant processes controlling groundwater hydrochemistry in the terrain. The trend of evolution of this set of processes follows the pattern of groundwater flow predicted by a calibrated transient groundwater model in the area. The data suggest that anthropogenic activities represent the second most important process in the hydrochemistry. Silicate mineral weathering is the third most important set of processes. Groundwater associations resulting from Q-mode hierarchical cluster analysis indicate an evolutionary pattern consistent with the general groundwater flow pattern in the basin. These key findings are at variance with results of previous investigations and indicate that when carefully done, groundwater hydrochemical data can be very useful for conceptualizing groundwater flow in basins.

  7. A new groundwater radiocarbon correction approach accounting for palaeoclimate conditions during recharge and hydrochemical evolution: The Ledo-Paniselian Aquifer, Belgium

    Energy Technology Data Exchange (ETDEWEB)

    Blaser, P.C., E-mail: petra.blaser@petraconsult.com [Petraconsult buero fuer angewandte geologie dipl. geol. petra c. blaser, Bergstrasse 269, CH 8707 Uetikon am See (Switzerland); Coetsiers, M. [Laboratory for Applied Geology and Hydrogeology, Ghent University, B-9000 Ghent (Belgium); Aeschbach-Hertig, W. [Institut fuer Umweltphysik, Universitaet Heidelberg, D-69120 Heidelberg (Germany); Kipfer, R. [Department of Water Resources and Drinking Water, Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Duebendorf (Switzerland)] [Institute of Isotope Geochemistry and Mineral Resources, ETH Zurich, CH-8092 Zurich (Switzerland); Van Camp, M. [Laboratory for Applied Geology and Hydrogeology, Ghent University, B-9000 Ghent (Belgium); Loosli, H.H. [Department of Climate and Environmental Physics, University of Bern, CH 3012 Bern (Switzerland); Walraevens, K. [Laboratory for Applied Geology and Hydrogeology, Ghent University, B-9000 Ghent (Belgium)

    2010-03-15

    The particular objective of the present work is the development of a new radiocarbon correction approach accounting for palaeoclimate conditions at recharge and hydrochemical evolution. Relevant climate conditions at recharge are atmospheric pCO{sub 2} and infiltration temperatures, influencing C isotope concentrations in recharge waters. The new method is applied to the Ledo-Paniselian Aquifer in Belgium. This is a typical freshening aquifer where recharge takes place through the semi-confining cover of the Bartonian Clay. Besides cation exchange which is the major influencing process for the evolution of groundwater chemistry (particularly in the Bartonian Clay), also mixing with the original porewater solution (fossil seawater) occurs in the aquifer. Recharge temperatures were based on noble gas measurements. Potential infiltration water compositions, for a range of possible pCO{sub 2}, temperature and calcite dissolution system conditions, were calculated by means of PHREEQC. Then the sampled groundwaters were modelled starting from these infiltration waters, using the computer code NETPATH and considering a wide range of geochemical processes. Fitting models were selected on the basis of correspondence of calculated {delta}{sup 13}C with measured {delta}{sup 13}C. The {sup 14}C modelling resulted in residence times ranging from Holocene to Pleistocene (few hundred years to over 40 ka) and yielded consistent results within the uncertainty estimation. Comparison was made with the {delta}{sup 13}C and Fontes and Garnier correction models, that do not take climate conditions at recharge into account. To date these are considered as the most representative process-oriented existing models, yet differences in calculated residence times of mostly several thousands of years (up to 19 ka) are revealed with the newly calculated ages being mostly (though not always) younger. Not accounting for climate conditions at recharge (pCO{sub 2} and temperature) is thus producing

  8. Environmental hydrochemical and stabile isotope methods used to characterise the relation between karst water and surface water

    Directory of Open Access Journals (Sweden)

    Romeo Eftimi

    2017-03-01

    Full Text Available Karst aquifers are characterized by high heterogeneity of groundwater flow. The classical study methods such as boreholes, pumping tests, and point observations give important data but cannot be extended to the entire aquifer. However the environmental hydrochemical and stabile isotope methods could give important information about large scale aquifer characterization. Some study examples from Albania, shown in this paper, demonstrate the successful application of the isotope methods, which are more powerful if applied in combination with hydrochemical ones, for the identification of the karst water recharge sources. Among the isotope methods the altitude effect seems to be more indicative for the solution of the problem concerned. For characterising the lithology of karst rocks and the physical aspects of karst aquifers (type of groundwater flow the combined use of some hydrochemical parameters like the water conductivity, total hardness, ionic ratios rCa/ rMg, rSO4/r/mg, CO2 pressure and the indexes of calcite and (Sic and of dolomite saturation (Sid, result very useful.

  9. Hydrochemical characterization and pollution sources identification of groundwater in Salawusu aquifer system of Ordos Basin, China.

    Science.gov (United States)

    Yang, Qingchun; Wang, Luchen; Ma, Hongyun; Yu, Kun; Martín, Jordi Delgado

    2016-09-01

    Ordos Basin is located in an arid and semi-arid region of northwestern China, which is the most important energy source bases in China. Salawusu Formation (Q3 s) is one of the most important aquifer systems of Ordos Basin, which is adjacent to Jurassic coalfield areas. A large-scale exploitation of Jurassic coal resources over ten years results in series of influences to the coal minerals, such as exposed to the oxidation process and dissolution into the groundwater due to the precipitation infiltration. Therefore, how these processes impact groundwater quality is of great concerns. In this paper, the descriptive statistical method, Piper trilinear diagram, ratios of major ions and canonical correspondence analysis are employed to investigate the hydrochemical evolution, determine the possible sources of pollution processes, and assess the controls on groundwater compositions using the monitored data in 2004 and 2014 (before and after large-scale coal mining). Results showed that long-term exploration of coal resources do not result in serious groundwater pollution. The hydrochemical types changed from HCO3(-)-CO3(2-) facies to SO4(2-)-Cl facies during 10 years. Groundwater hardness, nitrate and sulfate pollution were identified in 2014, which was most likely caused by agricultural activities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Lessons learned from the use of hydrochemical data for the evaluation of the groundwater-flow models developed within the Swiss L/ILW programme

    International Nuclear Information System (INIS)

    Vomvoris, S.; Scholtis, A.; Vinard, P.; Waber, H.N.; Voborny, O.; Schindler, M.; Pearson, F.J.

    1999-01-01

    Hydrochemical data and their interpretations were used within the hydrogeological synthesis of the Swiss low and short-lived intermediate-level radioactive waste site to evaluate and improve the groundwater flow models. The groundwater flow models were developed on the basis of the structural geological models and hydraulic measurements, such as hydraulic conductivity and piezometric head profiles along seven deep boreholes. The hydrochemical interpretation for the deep circulation systems was based on samples collected in the deep boreholes and subsequent chemical and isotopic analyses. The lessons learned from the evaluation, which was abbreviated to the hydrochemical consistency check, result primarily from the fact that two different disciplines, which use models focusing on different processes, were brought together. The hydrochemical consistency check was proven to be very useful, both in terms of improving the groundwater flow models used in the synthesis but also in identifying the best process for performing similar comparisons in the future. (author)

  11. Hydrochemical processes in lowland rivers: insights from in situ, high-resolution monitoring

    Directory of Open Access Journals (Sweden)

    A. J. Wade

    2012-11-01

    Full Text Available This paper introduces new insights into the hydrochemical functioning of lowland river systems using field-based spectrophotometric and electrode technologies. The streamwater concentrations of nitrogen species and phosphorus fractions were measured at hourly intervals on a continuous basis at two contrasting sites on tributaries of the River Thames – one draining a rural catchment, the River Enborne, and one draining a more urban system, The Cut. The measurements complement those from an existing network of multi-parameter water quality sondes maintained across the Thames catchment and weekly monitoring based on grab samples. The results of the sub-daily monitoring show that streamwater phosphorus concentrations display highly complex dynamics under storm conditions dependent on the antecedent catchment wetness, and that diurnal phosphorus and nitrogen cycles occur under low flow conditions. The diurnal patterns highlight the dominance of sewage inputs in controlling the streamwater phosphorus and nitrogen concentrations at low flows, even at a distance of 7 km from the nearest sewage treatment works in the rural River Enborne. The time of sample collection is important when judging water quality against ecological thresholds or standards. An exhaustion of the supply of phosphorus from diffuse and multiple septic tank sources during storm events was evident and load estimation was not improved by sub-daily monitoring beyond that achieved by daily sampling because of the eventual reduction in the phosphorus mass entering the stream during events. The results highlight the utility of sub-daily water quality measurements and the discussion considers the practicalities and challenges of in situ, sub-daily monitoring.

  12. Influence of shear forces on the aggregation and sedimentation behavior of cerium dioxide (CeO{sub 2}) nanoparticles under different hydrochemical conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Bowen; Wang, Chao; Hou, Jun, E-mail: hhuhjyhj@126.com; Wang, Peifang, E-mail: pfwang2005@hhu.edu.cn; Miao, Lingzhan; Li, Yi; Ao, Yanhui; Yang, Yangyang; You, Guoxiang; Xu, Yi [Hohai University, Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education (China)

    2016-07-15

    This study contributed to a better understanding of the behavior of nanoparticles (NPs) in dynamic water. First, the aggregation behavior of CeO{sub 2} NPs at different pH values in various salt solutions was examined to determine the appropriate hydrochemical conditions for hydrodynamics study. Second, the aggregation behavior of CeO{sub 2} NPs under different shear forces was investigated at pH 4 and ionic strength 0 in various salt solutions to find out whether shear forces could influence the stability of the nanoparticles and if yes, how. Also, five-stage sedimentation tests were conducted to understand the influence of shear stress on the vertical distribution of CeO{sub 2} NPs in natural waters. The aggregation test showed that the shear force could increase the collision efficiency between NPs during aggregation and cause a relatively large mass of NPs to remain in suspension. Consequently, the nanoparticles had a greater possibility of continued aggregation. The sedimentation test under static conditions indicated that a large mass of NPs (>1000 nm) sink to the bottom layer, leaving only small aggregates dispersed in the upper or middle layer of the solution. However, later sedimentation studies under stirring conditions demonstrated that shear forces can disrupt this stratification phenomenon. These results suggest that shear forces can influence the spatial distribution of NPs in natural waters, which might lead to different toxicities of CeO{sub 2} NPs to aquatic organisms distributed in the different water layers. This study contributes to a better understanding of nanomaterial toxicology and provides a way for further research.Graphical Abstract.

  13. Interrelationships and distribution of hydrochemical parameters in coastal waters off Visakhapatnam, east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.; Rao, T.V.N.; RamaRaju, V.S.; Rathod, V.; Suguna, C.

    The distribution of hydrochemical parameters in the coastal waters off Visakhapatnam during the July 1979-June 1980 showed distinct changes with time The observed supersaturation and saturation of oxygen in surface waters was due to favourable...

  14. Hydrochemical stability of groundwaters surrounding a spent nuclear fuel repository in a 100,000 year perspective

    International Nuclear Information System (INIS)

    Puigdomeneck, I.

    2001-09-01

    This report is focussed on the effects of climate changes on the chemical composition of deep groundwaters. The aim of the work has been to assess the hydrochemical stability at nuclear repository sites in Finland and Sweden. Sites investigated by SKB and POSIVA have been compared. The corresponding features are important in judging how sensitive a site might be to climatic changes. Evidence for climate effects in the past on groundwater compositions has been reviewed, including isotopic and mineralogical data. There is for example evidence that glacial meltwaters are currently present at repository depths in the Fennoscandian Shield. No evidence has been found however that oxidising conditions have ever prevailed at depth, even if glacial meltwaters presumably had a substantial amount of dissolved O 2 . The depth distribution of different calcite types (and other fracture minerals) indicates stability in large-scale groundwater circulation over time. Information on past (and future) groundwater salinities has been sought after in the results of hydrological numerical models for Aespoe in Sweden and Olkiluoto in Finland. It is expected that groundwater salinities will change due to future climatic variations. The main effects will be from shoreline movements, permafrost and continental ice-sheets. In most sites the present reducing redox conditions will remain undisturbed during glacial cycles. The modelling indicated that most of the SKB suitability criteria will be met during the life-span of the repository and the groundwater composition will vary within what is observed in the samples collected today at various depths. The expected changes are therefore not judged to threaten the integrity and functioning of the repository. The major conclusion is that despite long-term hydrodynamic changes hydrochemical stability is expected to dominate at repository depth

  15. Hydrochemical stability of groundwaters surrounding a spent nuclear fuel repository in a 100,000 year perspective

    Energy Technology Data Exchange (ETDEWEB)

    Puigdomeneck, I. (ed.)

    2001-09-01

    This report is focussed on the effects of climate changes on the chemical composition of deep groundwaters. The aim of the work has been to assess the hydrochemical stability at nuclear repository sites in Finland and Sweden. Sites investigated by SKB and POSIVA have been compared. The corresponding features are important in judging how sensitive a site might be to climatic changes. Evidence for climate effects in the past on groundwater compositions has been reviewed, including isotopic and mineralogical data. There is for example evidence that glacial meltwaters are currently present at repository depths in the Fennoscandian Shield. No evidence has been found however that oxidising conditions have ever prevailed at depth, even if glacial meltwaters presumably had a substantial amount of dissolved O{sub 2}. The depth distribution of different calcite types (and other fracture minerals) indicates stability in large-scale groundwater circulation over time. Information on past (and future) groundwater salinities has been sought after in the results of hydrological numerical models for Aespoe in Sweden and Olkiluoto in Finland. It is expected that groundwater salinities will change due to future climatic variations. The main effects will be from shoreline movements, permafrost and continental ice-sheets. In most sites the present reducing redox conditions will remain undisturbed during glacial cycles. The modelling indicated that most of the SKB suitability criteria will be met during the life-span of the repository and the groundwater composition will vary within what is observed in the samples collected today at various depths. The expected changes are therefore not judged to threaten the integrity and functioning of the repository. The major conclusion is that despite long-term hydrodynamic changes hydrochemical stability is expected to dominate at repository depth.

  16. Hydrochemical stability of groundwaters surrounding a spent nuclear fuel repository in a 100,000 year perspective

    Energy Technology Data Exchange (ETDEWEB)

    Puigdomenech, I. (ed.); Gurban, I.; Laaksoharju, M. [and others

    2001-12-01

    This report is focused on the effects of climate changes on the chemical composition of deep groundwaters. The aim of the work has been to assess the hydrochemical stability at nuclear repository sites in Finland and Sweden. Sites investigated by SKB and POSIVA have been compared. The corresponding features are important in judging how sensitive a site might be to climatic changes. Evidence for climate effects in the past on groundwater compositions has been reviewed, including isotopic and mineralogical data. There is for example evidence that glacial meltwaters are currently present at repository depths in the Fennoscandian Shield. No evidence has been found however that oxidising conditions have ever prevailed at depth, even if glacial meltwaters presumably had a substantial amount of dissolved 0{sub 2}. The depth distribution of different calcite types (and other fracture minerals) indicates stability in large-scale groundwater circulation over time. Information on past (and future) groundwater salinities has been sought after in the results of hydrological numerical models for Aespoe in Sweden and Olkiluoto in Finland. It is expected that groundwater salinities will change due to future climatic variations. The main effects will be from shoreline movements, permafrost and continental ice-sheets. In most sites the present reducing redox conditions will remain undisturbed during glacial cycles. The modelling indicated that most of the SKB suitability criteria will be met during the life-span of the repository and the groundwater composition will vary within what is observed in the samples collected today at various depths. The expected changes are therefore not judged to threaten the integrity and functioning of the repository. The major conclusion is that despite long-term hydrodynamic changes hydrochemical stability is expected to dominate at repository depth. (orig.)

  17. Hydrochemical and isotopic studies of ground water from Botucatu Aquifer - Partial results for North region of Parana Basin

    International Nuclear Information System (INIS)

    Silva, R.B.G. da; Kimmelmann, A.A.; Cunha Reboucas, A. da

    1985-01-01

    The first results of an investigation, to study the flow path, the processes controlling the chemical composition, the recharge, as well as, the origin, apparent ages and dynamic of the groundwater of the Botucatu Aquifer in the Brazilian part of the Parana Basin (818.000 Km 2 ), using hydrochemical and environmental isotope technics ( 2 H, 18 O, 13 C, 3 H, 14 C), are presented. Samples of 20 deep wells, located in the northern part of the Basin (states of Sao Paulo, Mato Grosso do Sul and Goias), were analysed. (Author) [pt

  18. Testing and validation of numerical models of groundwater flow, solute transport and chemical reactions in fractured granites: A quantitative study of the hydrogeological and hydrochemical impact produced

    Energy Technology Data Exchange (ETDEWEB)

    Molinero Huguet, J

    2001-07-01

    This work deals with numerical modeling of groundwater flow, solute transport and chemical reactions through fractured media. These models have been developed within the framework of research activities founded by ENRESA , the Spanish Company for Nuclear Waste Management. This project is the result of a collaborative agreement between ENRESA and his equivalent Swedish Company (SKB) through the research project Task Force 5 of the Aspo Underground Laboratory. One of the objectives of this project is to assess quantitatively th hydrogeological and hydrochemical impact produced by the construction of a Deep Geological Repository in fractured granites. This is important because the new conditions altered construction impact will constitute the initial conditions for the repository closure stage. A second goo l of this work deals with testing the ability of current numerical tools to cope simultaneously with the complex hydrogeological and hydrochemical settlings, which are expected to take place in actual nuclear waste underground repositories constructed in crystalline fractured bed racks. This study has been undertaken through the performance of numerical models, which have subsequently been applied to simulate the hydrogeological and hydrochemical behavior of a granite massif, at a kilo metrical scale, during construction of the Aspo Hard Rock Underground Laboratory (Sweden). The Aspo Hard Rock Laboratory is a prototype, full-scale underground facility launched and operated by SKB. The main aim of the laboratory is to provide an opportunity for research, development and demonstration in a realistic rock environment down to the depth planned for the future deep repository. The framework of this underground facility provides a unique opportunity to attempt the objectives of the present dissertation. (Author)

  19. Testing and validation of numerical models of groundwater flow, solute transport and chemical reactions in fractured granites: A quantitative study of the hydrogeological and hydrochemical impact produced

    International Nuclear Information System (INIS)

    Molinero Huguet, J.

    2001-06-01

    This work deals with numerical modeling of groundwater flow, solute transport and chemical reactions through fractured media. These models have been developed within the framework of research activities founded by ENRESA , the Spanish Company for Nuclear Waste Management. This project is the result of a collaborative agreement between ENRESA and his equivalent Swedish Company (SKB) through the research project Task Force 5 of the Aspo Underground Laboratory. One of the objectives of this project is to assess quantitatively th hydrogeological and hydrochemical impact produced by the construction of a Deep Geological Repository in fractured granites. This is important because the new conditions altered construction impact will constitute the initial conditions for the repository closure stage. A second goo l of this work deals with testing the ability of current numerical tools to cope simultaneously with the complex hydrogeological and hydrochemical settlings, which are expected to take place in actual nuclear waste underground repositories constructed in crystalline fractured bed racks. This study has been undertaken through the performance of numerical models, which have subsequently been applied to simulate the hydrogeological and hydrochemical behavior of a granite massif, at a kilo metrical scale, during construction of the Aspo Hard Rock Underground Laboratory (Sweden). The Aspo Hard Rock Laboratory is a prototype, full-scale underground facility launched and operated by SKB. The main aim of the laboratory is to provide an opportunity for research, development and demonstration in a realistic rock environment down to the depth planned for the future deep repository. The framework of this underground facility provides a unique opportunity to attempt the objectives of the present dissertation. (Author)

  20. Seasonal hydrochemical variation in a tropical coastal lagoon (Açu Lagoon, Brazil

    Directory of Open Access Journals (Sweden)

    G. G. Chagas

    Full Text Available Hydrochemical conditions in the Açu Lagoon are described using spatial and temporal variations of various limnological variables (water temperature, dissolved oxygen, electric conductivity, total alkalinity, carbon dioxide, dissolved and total nutrients (N, P and Si, and chlorophyll a. Collected data was used in order to understand the structure and functioning of an enclosed coastal lagoon strongly influenced by climatic conditions. Water samples were collected monthly (November 1999-December 2000 in five sampling stations established along the lagoon. A decreasing spatial gradient of electrical conductivity was observed beginning from a sand bar region between the lagoon and the sea in the direction of the sweet-water input area. The positive correlation observed between the pH and dissolved oxygen (DO values, and the negative one observed between pH values and those of carbon dioxide (CO2, evidenced coupled biological processes, e.g., primary production and decomposition. Both spatial and temporal variation of dissolved nutrients showed fast increase and decrease in the beginning of summer, suggesting that nutrient input resulting from rainfall stimulates phytoplankton production, as reflected by chlorophyll a concentration increase.

  1. Temporal hydrological and hydrochemical behaviour of the regional discharge area of a carbonate system - why we can not see fast responses?

    Science.gov (United States)

    Bodor, Petra; Eröss, Anita; Kovács, József; Mádl-Szönyi, Judit

    2016-04-01

    The subsurface part of the hydrologic cycle, the saturated groundwater flow can be mostly studied in regional discharge areas. In these regions the water has already spent geologically long time under the surface, therefore the upwelling water reflect the effect of the geometry and boundary conditions of the whole flow field, its geology and chemical processes. According to these conditions, the discharging waters can be characterized with different values and variability of physicochemical parameters (temperature, total dissolved solids, cations, anions, gas content etc.). This question has special interest in carbonate systems where the concept of regional groundwater flow was only introduced in the last few years. Hydrographs and chemographs are frequently used in karst studies to demonstrate the effect of variability of the system and to derive information for the nature of flow inside the karst (channel, fracture or matrix). Usually these graphs show abrupt changes after precipitation events, but this is typical for epigenic karsts. However, discharge areas, where hypogenic karsts developed, can behave differently due to their feeding flow systems. These systems and their effects are not so well studied yet. In this study we examined hydrographs and chemographs of the regional discharge area of a deep and thick carbonate range of Buda Thermal Karst and tried to understand those mechanisms which determine the hydrological and hydrochemical behaviour of the region. Here cold, lukewarm and also thermal waters discharge along the River Danube. The variability of physicochemical parameters (temperature, electric conductivity, pH, volume discharge, water level, dissolved CO2 and 222Rn, δ18O, δD) of the discharging water was studied to understand influencing mechanisms. We tried to understand the effect of precipitation (short and long term) and the effect of River Danube with geomathematical methods for the lukewarm components of the discharging water. Based on

  2. Variability and Uncertainties of Key Hydrochemical Parameters for SKB Sites

    Energy Technology Data Exchange (ETDEWEB)

    Bath, Adrian [Intellisci Ltd, Willoughby on the Wolds, Loughborough (United Kingdom); Hermansson, Hans-Peter [Studsvik Nuclear AB, Nykoeping (Sweden)

    2006-12-15

    The work described in this report is a development of SKI's capability for the review and evaluation of data that will constitute part of SKB's case for selection of a suitable site and application to construct a geological repository for spent nuclear fuel. The aim has been to integrate a number of different approaches to interpreting and evaluating hydrochemical data, especially with respect to the parameters that matter most in assessing the suitability of a site and in understanding the geochemistry and groundwater conditions at a site. It has been focused on taking an independent view of overall uncertainties in reported data, taking account of analytical, sampling and other random and systematic sources of error. This evaluation was carried out initially with a compilation and general inspection of data from the Simpevarp, Forsmark and Laxemar sites plus data from older 'historical' boreholes in the Aespoe area. That was followed by a more specific interpretation by means of geochemical calculations which test the robustness of certain parameters, namely pH and redox/Eh. Geochemical model calculations have been carried out with widely available computer software. Data sources and their handling were also considered, especially access to SKB's SICADA database. In preparation for the use of geochemical modelling programs and to establish comparability of model results with those reported by SKB, the underlying thermodynamic databases were compared with each other and with other generally accepted databases. Comparisons of log K data for selected solid phases and solution complexes from the different thermodynamic databases were made. In general, there is a large degree of comparability between the databases, but there are some significant, and in a few cases large, differences. The present situation is however adequate for present purposes. The interpretation of redox equilibria is dependent on identifying the relevant solid phases and

  3. Insights into hydrologic and hydrochemical processes based on concentration-discharge and end-member mixing analyses in the mid-Merced River Basin, Sierra Nevada, California

    Science.gov (United States)

    Liu, Fengjing; Conklin, Martha H.; Shaw, Glenn D.

    2017-01-01

    Both concentration-discharge relation and end-member mixing analysis were explored to elucidate the connectivity of hydrologic and hydrochemical processes using chemical data collected during 2006-2008 at Happy Isles (468 km2), Pohono Bridge (833 km2), and Briceburg (1873 km2) in the snowmelt-fed mid-Merced River basin, augmented by chemical data collected by the USGS during 1990-2014 at Happy Isles. Concentration-discharge (C-Q) in streamflow was dominated by a well-defined power law relation, with the magnitude of exponent (0.02-0.6) and R2 values (p lower on rising than falling limbs. Concentrations of conservative solutes in streamflow resulted from mixing of two end-members at Happy Isles and Pohono Bridge and three at Briceburg, with relatively constant solute concentrations in end-members. The fractional contribution of groundwater was higher on rising than falling limbs at all basin scales. The relationship between the fractional contributions of subsurface flow and groundwater and streamflow (F-Q) followed the same relation as C-Q as a result of end-member mixing. The F-Q relation was used as a simple model to simulate subsurface flow and groundwater discharges to Happy Isles from 1990 to 2014 and was successfully validated by solute concentrations measured by the USGS. It was also demonstrated that the consistency of F-Q and C-Q relations is applicable to other catchments where end-members and the C-Q relationships are well defined, suggesting hydrologic and hydrochemical processes are strongly coupled and mutually predictable. Combining concentration-discharge and end-member mixing analyses could be used as a diagnostic tool to understand streamflow generation and hydrochemical controls in catchment hydrologic studies.

  4. Site investigation - equipment for geological, geophysical, hydrogeological and hydrochemical characterization

    International Nuclear Information System (INIS)

    Almen, K.E.; Fridh, B.; Johansson, B.E.; Sehlstedt, M.

    1986-11-01

    The investigations are performed within a site investigation program. In total about 60,000 m of cored 56 mm boreholes have been drilled and investigated at eight study sites. A summarized description of the main investigation methods is included. Instruments for geophysical investigations contains equipment for ground measurements as well as for borehole logging. The Geophysical investigations including the borehole radar measurements, are indirect methods for the geological and hydrogeological characterization of the rock formation. Great effort has been laid on the development of hydrogeological instruments for hydraulic tests and groundwater head measurements. In order to obtain hydrochemical investigations with high quality, a complete system for sampling and analysis of ground water has been developed. (orig./PW)

  5. The international project of radiation and hydrochemical investigation and monitoring of general Caspian rivers

    International Nuclear Information System (INIS)

    Passell, H.D.; Barber, D.S.; Kadyrzhanov, K.K; Solodukhin, V.P.; Chernykh, E.E.; Arutyunyan, R.V.; Valyaev, A.N.; Kadik, A.A.; Stepanetts, O.V; Vernadsky, V.I.; Alizade, A.A.; Gutiev, I.S.; Mamedov, R.F.; Nadareishvili, K.S.; Chkhartishvili, A.G.; Tsitskishvili, M.S.; Chubaryan, E. V; Gevorgyan, R.G.; Puskyulyan, K.I.

    2005-01-01

    Full text: The scientific community of six countries (USA, Kazakhstan, Russia, Georgia, Armenia, and Azerbaijan) has developed the ecological project 'Joint International Researches and Creation of the General System of Radiation and Hydro-chemical Monitoring of Rivers of the Caspian Sea Basin.' The purpose of this project is to investigate and characterized contamination by radionuclides and toxic and chemically hazardous elements and create a valid system of radiation and hydro-chemical monitoring of the main river basins of the Caspian region: the Volga, Ural, Emba and Kura. The basins of these rivers cover large parts of Europe and Asia, including parts of Russia, West Kazakhstan and the South Caucasus and including territories of Georgia, Armenia and Azerbaijan. The total area of the basins of these rivers exceeds combined area of such large European states as France, Spain and Germany, and comprises 1631 sq. km. All these rivers are the main life-supporting water arteries for the region's inhabitants, a population that comprises tens of millions of people Also, the outlets of these rivers determine the condition of the aquatic environment of the Caspian Sea. The ecological condition of the aquatic environment of all the rivers of the Caspian Sea is to a great extent due to contamination, the main components of which are anthropogenic radioactive elements, heavy metals and oil products. At present, information about contamination levels of these rivers is not known and is occasionally contradictory. In this connection there is an obvious need of qualified investigation of contamination levels and its character in the basins of these rivers and in creating a common monitoring system to assess the quality of the aquatic environment. The present project is devoted to this matter. 1. The project provides for the following main tasks: 1. Wide-ranging investigation of the level and character of contamination by radionuclides and toxic elements of the river basins

  6. Evaluation of the Marine Intrusion in Havana Province Groundwater Using Hydrochemical and Isotopic Tools

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, A. M.; Bombuse, D. L.; Estevez Alvarez, J. R. [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear (CEADEN), Havana (Cuba); others, and

    2013-07-15

    In the present paper the spatial distribution and temporal evolution of the saline intrusion in the most important aquifer of Havana province is presented. Results were obtained through the application of hydrochemical and isotopic tools. Studies were carried out within the framework of the IAEA Regional Project RLA/8/041. The survey was carried out in 2008 during the dry and rainy seasons. Sampling points were selected according to a monitoring network located along the north-south line following the main groundwater flow direction. Stable isotopes ({sup 2}H and {sup 18}O) were used to identify and characterize the groundwater origin and mixing processes. Changes in the chemical composition of groundwater were shown to be mainly controlled by the groundwater and seawater mixing process, followed by cation exchange reactions and a Ca-Mg precipitation process due to the strong influence of the costal wetland. A gradual decreasing of the spatial and temporal saline intrusion was observed. (author)

  7. NODC Standard Product: International ocean atlas Volume 3 - Hydrochemical Atlas of the Sea of Okhotsk 2001 (NODC Accession 0000521)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hydrochemical and other data were collected from bottle casts in the Sea of Okhotsk from the Protractor from 01 June 1990 to 31 August 1997. Data were compiled as an...

  8. Using hydrochemical data and modelling to enhance the knowledge of groundwater flow and quality in an alluvial aquifer of Zagreb, Croatia

    Energy Technology Data Exchange (ETDEWEB)

    Marković, Tamara, E-mail: tmarkovic@hgi-cgs.hr; Brkić, Željka; Larva, Ozren

    2013-08-01

    The Zagreb alluvial aquifer system is located in the southwest of the Pannonian Basin in the Sava Valley in Croatia. It is composed of Quaternary unconsolidated deposits and is highly utilised, primarily as a water supply for the more than one million inhabitants of the capital city of Croatia. To determine the origin and dynamics of the groundwater and to enhance the knowledge of groundwater flow and the interactions between the groundwater and surface water, extensive hydrogeological and hydrochemical investigations have been completed. The groundwater levels monitored in nested observation wells and the lithological profile indicate that the aquifer is a single hydrogeologic unit, but the geochemical characteristics of the aquifer indicate stratification. The weathering of carbonate and silicate minerals has an important role in groundwater chemistry, especially in the area where old meanders of the Sava River existed. Groundwater quality was observed to be better in the deeper parts of the aquifer than in the shallower parts. Furthermore, deterioration of the groundwater quality was observed in the area under the influence of the landfill. The stable isotopic composition of all sampled waters indicates meteoric origin. NETPATH-WIN was used to calculate the mixing proportions between initial waters (water from the Sava River and groundwater from “regional” flow) in the final water (groundwater sampled from observation wells). According to the results, the mixing proportions of “regional” flow and the river water depend on hydrological conditions, the duration of certain hydrological conditions and the vicinity of the Sava River. Moreover, although the aquifer system behaves as a single hydrogeologic unit from a hydraulic point of view, it still clearly demonstrates geochemical stratification, which could be a decisive factor in future utilisation strategies for the aquifer system. - Highlights: • The Zagreb aquifer is the largest utilised source of

  9. A HYDROCHEMICAL HYBRID CODE FOR ASTROPHYSICAL PROBLEMS. I. CODE VERIFICATION AND BENCHMARKS FOR A PHOTON-DOMINATED REGION (PDR)

    International Nuclear Information System (INIS)

    Motoyama, Kazutaka; Morata, Oscar; Hasegawa, Tatsuhiko; Shang, Hsien; Krasnopolsky, Ruben

    2015-01-01

    A two-dimensional hydrochemical hybrid code, KM2, is constructed to deal with astrophysical problems that would require coupled hydrodynamical and chemical evolution. The code assumes axisymmetry in a cylindrical coordinate system and consists of two modules: a hydrodynamics module and a chemistry module. The hydrodynamics module solves hydrodynamics using a Godunov-type finite volume scheme and treats included chemical species as passively advected scalars. The chemistry module implicitly solves nonequilibrium chemistry and change of energy due to thermal processes with transfer of external ultraviolet radiation. Self-shielding effects on photodissociation of CO and H 2 are included. In this introductory paper, the adopted numerical method is presented, along with code verifications using the hydrodynamics module and a benchmark on the chemistry module with reactions specific to a photon-dominated region (PDR). Finally, as an example of the expected capability, the hydrochemical evolution of a PDR is presented based on the PDR benchmark

  10. Defining reference conditions for acidified waters using a modern analogue approach

    International Nuclear Information System (INIS)

    Simpson, Gavin L.; Shilland, Ewan M.; Winterbottom, Julie M.; Keay, Janey

    2005-01-01

    Analogue matching is a palaeolimnological technique that aims to find matches for fossil sediment samples from a set of modern surface sediment samples. Modern analogues were identified that closely matched the pre-disturbance conditions of eight of the UK Acid Waters Monitoring Network (AWMN) lakes using diatom- and cladoceran-based analogue matching. These analogue sites were assessed in terms of hydrochemistry, aquatic macrophytes and macro-invertebrates as to their suitability for defining wider hydrochemical and biological reference conditions for acidified sites within the AWMN. The analogues identified for individual AWMN sites show a close degree of similarity in terms of their hydrochemical characteristics, aquatic macrophytes and, to a lesser extent, macro-invertebrate fauna. The reference conditions of acidified AWMN sites are inferred to be less acidic than today and to support a wider range of acid-sensitive aquatic macrophyte and macro-invertebrate taxa than that recorded in the AWMN lakes over the period of monitoring since 1988. - The use of a palaeolimnological technique to identify modern ecological reference analogues for acidified lakes is demonstrated

  11. Hydrochemical characteristic of surface and groundwater Lisichansk and Almazno-Marevske geological and industrial districts Nnorth-Eastern Donbas

    Directory of Open Access Journals (Sweden)

    Udalov Y.V.

    2014-12-01

    Full Text Available Incorporates a complex of problems accompanying the operation of coal deposits of Donbass. See hydrochemical characteristics of surface and groundwater Lisichansk and Almazno-Maryevskogo geological and industrial areas of the North-Eastern Donbass. Identified the main hydrochemical features of the waste mine waters of the enterprises of the coal industry on the territory of the studies. It is established that the surface waters of the study area exposed to intensive anthropogenic influence. Set content of basic elements-pollutants in surface waters. It is revealed that this pollution is of a complex nature. Identifies key elements contained in the effluent of industrial enterprises. Analyzed that a change of the chemical composition of groundwater has led to increased hardness and mineralization of water in the main water intakes of the research area. Identifies key elements-contaminants in groundwater. It was found that as a result of mine dewatering groundwater level fell over an area of 200km2, far exceeding the area of coal mining. This operational reserves fresh underground waters in the groundwater runoff module 1.2 dm3 / sec. km2 decreased by 200 - 300 m3 / day. Within funnel depression hydraulic connection is created not only a few confined aquifers, but also located near the mine fields. For example, in the area of Stakhanov the Luhansk region in general depression funnel width of about 25 km and a depth of 600-800m were 8 mine ("Central Irmino", "Maximovska" Ilyich, named after I.V. Chesnokov, "Krivoy Rog", 11-RAD "Brjankovsky" and "Dzerzhinsk". The purpose of research is general hydrochemical characteristics and identification of key elements polluting surface and groundwater Lisichanskiy and diamond-Marevskogo geological and industrial areas of the North-East Donbas.

  12. Seawater intrusion mapping using electrical resistivity tomography and hydrochemical data. An application in the coastal area of eastern Thermaikos Gulf, Greece.

    Science.gov (United States)

    Kazakis, N; Pavlou, A; Vargemezis, G; Voudouris, K S; Soulios, G; Pliakas, F; Tsokas, G

    2016-02-01

    The aim of this study was to determine the extent and geometrical characteristics of seawater intrusion in the coastal aquifer of the eastern Thermaikos Gulf, Greece. Hydrochemical data and geoelectrical measurements were combined and supplemented to determine the hydrochemical regime of the study site in regard to seawater phenomena. Chemical analysis of groundwater was performed in 126 boreholes and fifteen electrical resistivity tomographies (ERT) were measured, whereas in two sites the ERT measurements were repeated following the wet season. The Cl(-) concentrations recorded reached 2240 mg/L indicating seawater intrusion which was also verified by ionic ratios. The ionic ratios were overlapped and a seawater intrusion map (SWIM) was produced. A significant part of the coastal aquifer (up to 150 km(2)) is influenced by seawater intrusion. The areas with the most intensive salinization are located between Nea Kallikratia-Epanomi and Aggelochori-Peraia. According to the ERTs, in the influenced areas the salinization of the aquifer exceeds 1 km toward the mainland and its depth reaches 200 m. In the area surrounding Thessaloniki airport, the ERTs revealed salinization of the upper aquifer to depths of up to 40 m, whereas the lower aquifer is uninfluenced. This abnormal distribution of seawater intrusion demonstrates the value of geoelectrical methods in the study of seawater intrusion especially in areas with limited available hydrochemical data. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Physical properties, hydrochemicals, depth, and other data using CTD casts from 1994-01-01 to 1994-12-31 (NODC Accession 9600128)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hydrophysical, hydrochemical, meteorological, and other data were collected using bottle and XBT casts in Pacific Ocean from January 1, 1994 to December 31, 1994....

  14. Development of new ultrafiltration techniques maintaining in-situ hydrochemical conditions for colloidal study

    International Nuclear Information System (INIS)

    Aosai, Daisuke; Yamamoto, Yuhei; Mizuno, Takashi

    2011-01-01

    Chemical state of elements in groundwater is one of the most important information for understanding behavior of elements in underground environment. Chemical state of elements controlled mainly by groundwater physico-chemical parameters. Because the change of physico-chemical parameters of groundwater, due to pressure release and oxidation during sampling, causes changes in chemical state of elements, systematic methodologies for understanding in situ chemical state is required. In this study, in order to understand chemical state of elements in groundwater, an ultrafiltration instrument for maintaining in-situ pressure and anaerobic conditions was developed. The instrument developed in this study for ultrafiltration made of passivated Stainless Used Steel (SUS) materials, was designed to keep groundwater samples maintaining in-situ pressure/anaerobic conditions. Ultrafiltration of groundwater was conducted at a borehole drilled from the 200 mbGL (meters below ground level) Sub-stage at a depth of 200 m at the Mizunami Underground Research Laboratory. Chemical analyses of groundwater were also conducted using samples filtered under both pressurized/anaerobic and atmospheric conditions and passivated SUS materials with different elapsed times after passivation. The results indicate that our ultrafiltration method is suitable for collection of filtered groundwater and passivation is an essential treatment before ultrafiltration. (author)

  15. Sensors, Cyberinfrastructure, and Examination of Hydrologic and Hydrochemical Response in the Little Bear River Observatory Test Bed

    Science.gov (United States)

    Horsburgh, J. S.; Stevens, D. K.; Tarboton, D. G.; Mesner, N. O.; Spackman Jones, A.

    2008-12-01

    The Little Bear River environmental observatory test bed is one of 11 test bed projects that are focused on developing techniques and technologies for environmental observatories ranging from innovative application of environmental sensors to publishing observations data in common formats that can be accessed by investigators nationwide. Specific objectives of the Little Bear test bed include the estimation of water quality constituent fluxes from surrogate data, relation of fluxes to watershed attributes and management practices, examination of high frequency hydrologic and hydrochemical responses, and development of cyberinfrastructure that supports these analyses and publication of the data. We have installed high frequency water quality and discharge monitoring instrumentation at seven locations in the Little Bear, along with two continuous weather stations. Cyberinfrastructure that has been implemented includes the sensors, a telemetry system that transmits data from the field to a central location, a central observations database, software that automates the ingestion of these data into the database so they are available in near real time, and software tools for screening and quality control of the raw data. We have implemented a CUAHSI Hydrologic Information System (HIS) Server that includes an instance of the Observations Data Model (ODM) relational database that stores the data, web services that provide programmatic data access over the Internet using WaterML, the Data Access System for Hydrology (DASH) that provides an Internet map based interface for data access, and the Time Series Analyst that provides Internet-based plotting and summary functionality. The high frequency data have illustrated the dynamic nature of hydrologic and hydrochemical response in the Little Bear as well as the importance of sampling frequency on estimation of constituent fluxes. Annual estimates of total phosphorus and total suspended solids loads vary over orders of magnitude

  16. Hydraulic and hydrochemical characterisation of argillaceous rocks

    International Nuclear Information System (INIS)

    1995-01-01

    Throughout the OECD member countries many national programmes on radioactive waste management are considering geological disposal in argillaceous media. In order to determine their suitability for waste disposal, evaluations and understanding of basic physical and chemical processes that govern radionuclides transport through these formations are required. Clay-rich media have a very marked capacity to retard the movement of radionuclides by sorption, filtration and other mechanisms. However, a complicating factor to make quantitative predictions of the performance of clay barriers is our incomplete knowledge of the mechanisms of groundwater and solute transport in compact clays. Application of hydraulic testing and groundwater sampling methods to low and very low permeability rocks, and in particular to argillaceous media, requires modifications in equipment, testing procedures, and interpretation methods. In this context, the NEA Coordinating Group on Site Evaluation and Design of Experiments for Radioactive Waste Disposal (SEDE) established the NEA Working Group on Measurement and Physical Understanding of Groundwater Flow through Argillaceous Media (the Clay Club) to address the many issues associated with this subject. The workshop on hydraulic and hydrochemical characteristics of argillaceous media was hosted by the British Geological Survey in Keyworth, United Kingdom, on 7-9 June 1994

  17. Inverse hydrochemical models of aqueous extracts tests

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, L.; Samper, J.; Montenegro, L.

    2008-10-10

    Aqueous extract test is a laboratory technique commonly used to measure the amount of soluble salts of a soil sample after adding a known mass of distilled water. Measured aqueous extract data have to be re-interpreted in order to infer porewater chemical composition of the sample because porewater chemistry changes significantly due to dilution and chemical reactions which take place during extraction. Here we present an inverse hydrochemical model to estimate porewater chemical composition from measured water content, aqueous extract, and mineralogical data. The model accounts for acid-base, redox, aqueous complexation, mineral dissolution/precipitation, gas dissolution/ex-solution, cation exchange and surface complexation reactions, of which are assumed to take place at local equilibrium. It has been solved with INVERSE-CORE{sup 2D} and been tested with bentonite samples taken from FEBEX (Full-scale Engineered Barrier EXperiment) in situ test. The inverse model reproduces most of the measured aqueous data except bicarbonate and provides an effective, flexible and comprehensive method to estimate porewater chemical composition of clays. Main uncertainties are related to kinetic calcite dissolution and variations in CO2(g) pressure.

  18. Hydrochemical and isotopic investigation of atmospheric precipitation in Beijing, China

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Yuanzheng, E-mail: diszyz@163.com [College of Water Sciences, Beijing Normal University, Beijing 100875 (China); Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education of China, Beijing 100875 (China); Wang, Jinsheng, E-mail: wangjs@bnu.edu.cn [College of Water Sciences, Beijing Normal University, Beijing 100875 (China); Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education of China, Beijing 100875 (China); Zhang, Yang [College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049 (China); Teng, Yanguo; Zuo, Rui; Huan, Huan [College of Water Sciences, Beijing Normal University, Beijing 100875 (China); Engineering Research Center of Groundwater Pollution Control and Remediation, Ministry of Education of China, Beijing 100875 (China)

    2013-07-01

    Precipitation water samples were collected at an urban site in Beijing in a hydrological cycle (July 2008–July 2009), and analyzed for TDS, total alkalinity, total hardness, free CO{sub 2}, soluble SiO{sub 2}, bromide, sulfide, phosphate, major ions (K{sup +}, Na{sup +}, Ca{sup 2+}, Mg{sup 2+}, NH{sub 4}{sup +}, HCO{sub 3}{sup −}, Cl{sup −}, SO{sub 4}{sup 2−}, NO{sub 3}{sup −}), trace elements (CO{sub 3}{sup 2−}, Mn, Sr{sup 2+}, Fe{sup 2+}, Fe{sup 3+}, Al, F{sup −}, NO{sub 2}{sup −}), stable isotopes ({sup 2}H and {sup 18}O), and radioactive isotope ({sup 3}H). In addition, available published hydrochemical and isotopic data of precipitation of Beijing in the past were also collected and conjointly analyzed. Most of the parameters of samples tested varied considerably in the hydrological cycle. In general, HCO{sub 3}{sup −} and SO{sub 4}{sup 2−}, and Ca{sup 2+} and NH{sub 4}{sup +} are the dominant anions and cations, respectively. Using Na{sup +} as an indicator of marine origin, and Al for the terrestrial inputs, the proportions of major elements from sea salt and terrestrial sources were estimated by using the combination of statistical analysis methods and analogy method. More than 70.1% of Cl{sup −}, 98.1% of Ca{sup 2+}, and 93.6% of K{sup +} were non-sea-salt origin, while more than 98.4% of Na{sup +} was from marine sources. The LMWL (Local Meteoric Water Line) was obtained with an equation of δ{sup 2}H = 7.0181δ{sup 18}O + 3.5231 (‰, R{sup 2} = 0.86, n = 36), which was similar to GMWL (Global Meteoric Water Line). δ{sup 2}H, δ{sup 18}O and Δ-excess changed radically with month and season, but had no apparent seasonal effect, precipitation amount effect, and temperature effect. The annual mean values of Δ-excess for 1979 (16.5‰) and 1980 (16.3‰) were much bigger than that for 2007 (7.2‰), 2008 (2.1‰) and 2009 (4.5‰). The composition of {sup 2}H and {sup 18}O was probably intrinsically determined by the sources of water

  19. Hydrogeologic and Hydrochemical Studies in a Semi-arid Watershed in Northern Mexico

    Science.gov (United States)

    Kretzschmar, T.; Vazquez, R.; Hinojosa, A.

    2006-12-01

    Within the Baja California panhandle exist quite a significant number of valleys which hydrogeology conditions are of great importance for the communities of the region. The Guadalupe Valley for example, located 30 km Northeast of Ensenada, hosts an important wine industry which presents a mayor factor for agriculture and tourism in Baja California. The irrigation is carried out basically by groundwater extracted from quaternary sediments filling this post-Miocene depression. Besides the intensive usage of the water by the wine industry in the Guadalupe Valley, the local waterworks installed in 1985 a gallery of 10 wells extracting around 320 l/s or 30 % of the total water extraction in the valley to supply the city of Ensenada with drinking water. A total of more than 500 wells with a combined annual consumption of about 28 Mio m3 are at the moment active in the valley. In the arid portions of northern Mexico Mountain front recharge presents an important recharge source for the alluvial aquifers. Other important sources directly related to precipitation are direct infiltration, recharge by surface water runoff in the arroyos as well as by active fault systems. The principal recharge sources for the Guadalupe Valley aquifer are the Sierra Juárez and the Guadalupe River. To be able to address the state of equilibrium of aquifer, recharge estimates for the watershed were calculated determining the runoff/infiltration relationships obtained by curve number determinations combined with the interpretation of satellite images. These results were integrated into an evaluation and hydrologic modeling of the hydrologic data pointing towards differences of up to over 50 percent in the recharge estimation in comparison to earlier studies carried out in the area. Furthermore hydrochemical and isotopic studies were carried out to show the effects of the excessive ground water extraction on the water quality of the aquifer. The hydrochemical data indicate that intense use of

  20. Evaluation of Nevsehir mineral waters by using hydrochemical and isotopic data, central Anatolia, Turkey

    International Nuclear Information System (INIS)

    Afsin, M.; Kavurmaci, M.

    2002-01-01

    Many mineral waters are located in Nevsehir and its vicinity. Corak, Karakaya and Guemueskent mineral waters are investigated in this study. The springs generally emerge along faults in the study area. The marbles of the Bozcaldag metamorphic basement rocks form the confined aquifer of the springs. The hydrochemical facies of the springs are Na-Ca-HCO 3 of Karakaya cold springs, Ca-HCO 3 of Guemueskent mineral waters; and Na-Cl-HCO 3 of Corak and Karakaya mineral waters, respectively. Because of the gas-mineral-water interaction, total mineralizations are high in a CO 2 dominated and low temperature mineral waters. The springs are of meteoric origin. Corak and Karakaya mineral waters might be contributed by older waters. The Karakaya cold spring is shallow circulated, while the mineral waters which have high the free CO 2 -gas are circulated groundwaters. In addition to the old travertines extending along faultlines, recent travertine depositions appear in places where mineral waters appear. The travertines in these regions are formed under certain conditions including low flow depth, turbulent flow, increasing pH values due to the loss of CO 2

  1. Mass transport in low permeability rocks under the influence of coupled thermomechanical and hydrochemical effects - an overview

    International Nuclear Information System (INIS)

    Tsang, C.F.

    1984-10-01

    The present paper gives a general overview of mass transport in low permeability rocks under the coupled thermomechanical and hydrochemical effects associated with a nuclear waste repository. A classification of coupled processes is given. Then an ess is presented. example of a coupled process is presented. Discussions of coupled processes based on a recent LBL Panel meeting are summarized. 5 references, 3 figures, 4 tables

  2. Evaluation of groundwater quality and suitability for irrigation and drinking purposes in southwest Punjab, India using hydrochemical approach

    Science.gov (United States)

    Sharma, Diana Anoubam; Rishi, Madhuri S.; Keesari, Tirumalesh

    2017-10-01

    Groundwater samples from alluvial aquifers of Bathinda district, southwest Punjab were measured for physicochemical parameters as well as major ion chemistry to evaluate the groundwater suitability for drinking and irrigation purposes and to present the current hydrochemical status of groundwater of this district. Temporal variations were analyzed by comparing the pre- and post-monsoon groundwater chemistry. Most of the samples showed contamination: F- (72 %), Mg2+ (22 %), SO4 2- (28 %), TH (25 %), NO3 - (22 %), HCO3 - (22 %) and TDS (11 %) during pre-monsoon and F- (50 %), Mg2+ (39 %), SO4 2- (22 %), TH (28 %), NO3 - (22 %) and TDS (28 %) during post-monsoon above permissible limits for drinking, while rest of the parameters fall within the limits. Irrigation suitability was checked using sodium absorption ratio (SAR), residual sodium carbonate (RSC), percent sodium (Na%) and permeability index (PI). Most of the samples fall under good to suitable category during pre-monsoon period, but fall under doubtful to unsuitable category during post-monsoon period. Presence of high salt content in groundwater during post-monsoon season reflects leaching of salts present in the unsaturated zone by infiltrating precipitation. Hydrochemical data was interpreted using Piper's trilinear plot and Chadha's plot to understand the various geochemical processes affecting the groundwater quality. The results indicate that the order of cation dominance is Na+ > Mg2+ > Ca2+, while anion dominance is in the order Cl- > HCO3 - > SO4 2-. The geochemistry of groundwater of this district is mainly controlled by the carbonate and silicate mineral dissolution and ion exchange during pre-monsoon and leaching from the salts deposited in vadose zone during post-monsoon. The main sources of contamination are soluble fertilizers and livestock wastes. This study is significant as the surface water resources are limited and the quality and quantity of groundwater are deteriorating with time due to

  3. Innovative Methods for Integrating Knowledge for Long-Term Monitoring of Contaminated Groundwater Sites: Understanding Microorganism Communities and their Associated Hydrochemical Environment

    Science.gov (United States)

    Mouser, P. J.; Rizzo, D. M.; Druschel, G.; O'Grady, P.; Stevens, L.

    2005-12-01

    This interdisciplinary study integrates hydrochemical and genome-based data to estimate the redox processes occurring at long-term monitoring sites. Groundwater samples have been collected from a well-characterized landfill-leachate contaminated aquifer in northeastern New York. Primers from the 16S rDNA gene were used to amplify Bacteria and Archaea in groundwater taken from monitoring wells located in clean, fringe, and contaminated locations within the aquifer. PCR-amplified rDNA were digested with restriction enzymes to evaluate terminal restriction fragment length polymorphism (T-RFLP) community profiles. The rDNA was cloned, sequenced, and partial sequences were matched against known organisms using the NCBI Blast database. Phylogenetic trees and bootstrapping were used to identify classifications of organisms and compare the communities from clean, fringe, and contaminated locations. We used Artificial Neural Network (ANN) models to incorporate microbial data with hydrochemical information for improving our understanding of subsurface processes.

  4. Generation of Complex Karstic Conduit Networks with a Hydro-chemical Model

    Science.gov (United States)

    De Rooij, R.; Graham, W. D.

    2016-12-01

    The discrete-continuum approach is very well suited to simulate flow and solute transport within karst aquifers. Using this approach, discrete one-dimensional conduits are embedded within a three-dimensional continuum representative of the porous limestone matrix. Typically, however, little is known about the geometry of the karstic conduit network. As such the discrete-continuum approach is rarely used for practical applications. It may be argued, however, that the uncertainty associated with the geometry of the network could be handled by modeling an ensemble of possible karst conduit networks within a stochastic framework. We propose to generate stochastically realistic karst conduit networks by simulating the widening of conduits as caused by the dissolution of limestone over geological relevant timescales. We illustrate that advanced numerical techniques permit to solve the non-linear and coupled hydro-chemical processes efficiently, such that relatively large and complex networks can be generated in acceptable time frames. Instead of specifying flow boundary conditions on conduit cells to recharge the network as is typically done in classical speleogenesis models, we specify an effective rainfall rate over the land surface and let model physics determine the amount of water entering the network. This is advantageous since the amount of water entering the network is extremely difficult to reconstruct, whereas the effective rainfall rate may be quantified using paleoclimatic data. Furthermore, we show that poorly known flow conditions may be constrained by requiring a realistic flow field. Using our speleogenesis model we have investigated factors that influence the geometry of simulated conduit networks. We illustrate that our model generates typical branchwork, network and anastomotic conduit systems. Flow, solute transport and water ages in karst aquifers are simulated using a few illustrative networks.

  5. Assessment of water quality of a river-dominated estuary with hydrochemical parameters: A statistical approach.

    Digital Repository Service at National Institute of Oceanography (India)

    Padma, P.; Sheela, V.S.; Suryakumari, S.; Jayalakshmy, K.V.; Nair, S.M.; Kumar, N.C.

    stream_size 64084 stream_content_type text/plain stream_name Water_Qual_Expos_Health_5_197.pdf.txt stream_source_info Water_Qual_Expos_Health_5_197.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8... Water Qual Expo Health DOI 10.1007/s12403-014-0115-9 ORIGINAL PAPER Assessment of Water Quality of a River-Dominated Estuary with Hydrochemical Parameters: A Statistical Approach P. Padma · V. S. Sheela · S. Suryakumari · K. V. Jayalakshmy · S. M. Nair...

  6. Seawater intrusion mapping using electrical resistivity tomography and hydrochemical data. An application in the coastal area of eastern Thermaikos Gulf, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Kazakis, N., E-mail: kazanera@yahoo.com [Aristotle University of Thessaloniki, Department of Geology, Lab. of Engineering Geology & Hydrogeology, 54124 Thessaloniki (Greece); Pavlou, A. [Aristotle University of Thessaloniki, Department of Geology, Lab. of Engineering Geology & Hydrogeology, 54124 Thessaloniki (Greece); Vargemezis, G. [Aristotle University of Thessaloniki, Department of Geology, Lab. of Applied Geophysics, 54124 Thessaloniki (Greece); Voudouris, K.S.; Soulios, G. [Aristotle University of Thessaloniki, Department of Geology, Lab. of Engineering Geology & Hydrogeology, 54124 Thessaloniki (Greece); Pliakas, F. [Democritus University of Thrace, Department of Civil Engineering, Xanthi 67100 (Greece); Tsokas, G. [Aristotle University of Thessaloniki, Department of Geology, Lab. of Applied Geophysics, 54124 Thessaloniki (Greece)

    2016-02-01

    The aim of this study was to determine the extent and geometrical characteristics of seawater intrusion in the coastal aquifer of the eastern Thermaikos Gulf, Greece. Hydrochemical data and geoelectrical measurements were combined and supplemented to determine the hydrochemical regime of the study site in regard to seawater phenomena. Chemical analysis of groundwater was performed in 126 boreholes and fifteen electrical resistivity tomographies (ERT) were measured, whereas in two sites the ERT measurements were repeated following the wet season. The Cl{sup −} concentrations recorded reached 2240 mg/L indicating seawater intrusion which was also verified by ionic ratios. The ionic ratios were overlapped and a seawater intrusion map (SWIM) was produced. A significant part of the coastal aquifer (up to 150 km{sup 2}) is influenced by seawater intrusion. The areas with the most intensive salinization are located between Nea Kallikratia–Epanomi and Aggelochori–Peraia. According to the ERTs, in the influenced areas the salinization of the aquifer exceeds 1 km toward the mainland and its depth reaches 200 m. In the area surrounding Thessaloniki airport, the ERTs revealed salinization of the upper aquifer to depths of up to 40 m, whereas the lower aquifer is uninfluenced. This abnormal distribution of seawater intrusion demonstrates the value of geoelectrical methods in the study of seawater intrusion especially in areas with limited available hydrochemical data. - Highlights: • ERTs determined the geometrical characteristics of the saline aquifer. • An abnormal distribution of seawater intrusion was recorded. • Four ionic ratios overlapped and a seawater intrusion map was produced. • Cl{sup −} concentrations increased significantly from 2005 to 2010 by up to 1800 mg/L.

  7. Seawater intrusion mapping using electrical resistivity tomography and hydrochemical data. An application in the coastal area of eastern Thermaikos Gulf, Greece

    International Nuclear Information System (INIS)

    Kazakis, N.; Pavlou, A.; Vargemezis, G.; Voudouris, K.S.; Soulios, G.; Pliakas, F.; Tsokas, G.

    2016-01-01

    The aim of this study was to determine the extent and geometrical characteristics of seawater intrusion in the coastal aquifer of the eastern Thermaikos Gulf, Greece. Hydrochemical data and geoelectrical measurements were combined and supplemented to determine the hydrochemical regime of the study site in regard to seawater phenomena. Chemical analysis of groundwater was performed in 126 boreholes and fifteen electrical resistivity tomographies (ERT) were measured, whereas in two sites the ERT measurements were repeated following the wet season. The Cl"− concentrations recorded reached 2240 mg/L indicating seawater intrusion which was also verified by ionic ratios. The ionic ratios were overlapped and a seawater intrusion map (SWIM) was produced. A significant part of the coastal aquifer (up to 150 km"2) is influenced by seawater intrusion. The areas with the most intensive salinization are located between Nea Kallikratia–Epanomi and Aggelochori–Peraia. According to the ERTs, in the influenced areas the salinization of the aquifer exceeds 1 km toward the mainland and its depth reaches 200 m. In the area surrounding Thessaloniki airport, the ERTs revealed salinization of the upper aquifer to depths of up to 40 m, whereas the lower aquifer is uninfluenced. This abnormal distribution of seawater intrusion demonstrates the value of geoelectrical methods in the study of seawater intrusion especially in areas with limited available hydrochemical data. - Highlights: • ERTs determined the geometrical characteristics of the saline aquifer. • An abnormal distribution of seawater intrusion was recorded. • Four ionic ratios overlapped and a seawater intrusion map was produced. • Cl"− concentrations increased significantly from 2005 to 2010 by up to 1800 mg/L.

  8. Hydrochemical processes in a shallow coal seam gas aquifer and its overlying stream–alluvial system: implications for recharge and inter-aquifer connectivity

    International Nuclear Information System (INIS)

    Duvert, Clément; Raiber, Matthias; Owen, Daniel D.R.; Cendón, Dioni I.; Batiot-Guilhe, Christelle; Cox, Malcolm E.

    2015-01-01

    Highlights: • Major ions and isotopes used to study inter-aquifer mixing in a shallow CSG setting. • Considerable heterogeneity in the water composition of the coal-bearing aquifer. • Rapid recharge of the coal-bearing aquifer through highly fractured igneous rocks. • Potential mixing between the coal-bearing aquifer and downstream alluvial aquifer. • Need to consider the seasonal influences on inter-aquifer mixing in CSG settings. - Abstract: In areas of potential coal seam gas (CSG) development, understanding interactions between coal-bearing strata and adjacent aquifers and streams is of highest importance, particularly where CSG formations occur at shallow depth. This study tests a combination of hydrochemical and isotopic tracers to investigate the transient nature of hydrochemical processes, inter-aquifer mixing and recharge in a catchment where the coal-bearing aquifer is in direct contact with the alluvial aquifer and surface drainage network. A strong connection was observed between the main stream and underlying alluvium, marked by a similar evolution from fresh Ca–Mg–HCO 3 waters in the headwaters towards brackish Ca–Na–Cl composition near the outlet of the catchment, driven by evaporation and transpiration. In the coal-bearing aquifer, by contrast, considerable site-to-site variations were observed, although waters generally had a Na–HCO 3 –Cl facies and high residual alkalinity values. Increased salinity was controlled by several coexisting processes, including transpiration by plants, mineral weathering and possibly degradation of coal organic matter. Longer residence times and relatively enriched carbon isotopic signatures of the downstream alluvial waters were suggestive of potential interactions with the shallow coal-bearing aquifer. The examination of temporal variations in deuterium excess enabled detection of rapid recharge of the coal-bearing aquifer through highly fractured igneous rocks, particularly at the catchment

  9. High-resolution monitoring across the soil-groundwater interface - Revealing small-scale hydrochemical patterns with a novel multi-level well

    Science.gov (United States)

    Gassen, Niklas; Griebler, Christian; Stumpp, Christine

    2016-04-01

    Biogeochemical turnover processes in the subsurface are highly variable both in time and space. In order to capture this variability, high resolution monitoring systems are required. Particular in riparian zones the understanding of small-scale biogeochemical processes is of interest, as they are regarded as important buffer zones for nutrients and contaminants with high turnover rates. To date, riparian research has focused on influences of groundwater-surface water interactions on element cycling, but little is known about processes occurring at the interface between the saturated and the unsaturated zone during dynamic flow conditions. Therefore, we developed a new type of high resolution multi-level well (HR-MLW) that has been installed in the riparian zone of the Selke river. This HR-MLW for the first time enables to derive water samples both from the unsaturated and the saturated zone across one vertical profile with a spatial vertical resolution of 0.05 to 0.5 m to a depth of 4 m b.l.s. Water samples from the unsaturated zone are extracted via suction cup sampling. Samples from the saturated zone are withdrawn through glass filters and steel capillaries. Both, ceramic cups and glass filters, are installed along a 1" HDPE piezometer tube. First high resolution hydrochemical profiles revealed a distinct depth-zonation in the riparian alluvial aquifer. A shallow zone beneath the water table carried a signature isotopically and hydrochemically similar to the nearby river, while layers below 1.5 m were influenced by regional groundwater. This zonation showed temporal dynamics related to groundwater table fluctuations and microbial turnover processes. The HR-MLW delivered new insight into mixing and turnover processes between riverwater and groundwater in riparian zones, both in a temporal and spatial dimension. With these new insights, we are able to improve our understanding of dynamic turnover processes at the soil - groundwater interface and of surface

  10. Environmental isotopes and hydrochemical study of groundwater in the north eastern portions of the delta of wadi El-Arish, Sinai, Egypt

    International Nuclear Information System (INIS)

    Nada, A.; Aly, A.I.M.; Awad, M.; El-Behery, M.A.; Hamza, M.S.

    1991-01-01

    An environmental isotopes and hydrochemical study was conducted on the underground water bearing strata in the northern part of Wadi El-Arish area, sinai. Wadi El-Arish area represents one of the most important areas for future agricultural expansion in the sinai peninsula. The purpose of the study is to determine whether the groundwater is recently recharged or not in order to adopt an efficient management policy. The hydrochemical results indicate the meteoric origin of the water with some contribution from sea water and old marine water. The tritium data confirm the meteoric origin of the water and indicate the recharge of groundwater in the study area in the last 20 years. The stable environmental isotopic composition of the groundwater (oxygen-18 and deuterium) reflects more or less the isotopic composition of precipitation and flooding within the delta of the wadi to infiltration. There is also a possibility, of contribution from palea-water (depleted in the environmental stable isotopes) in some wells by leaking through faulting in this area.7 fig,2 tab

  11. Field-testing competing runoff source and hydrochemical conceptualisations

    Science.gov (United States)

    Western, A. W.; Saffarpour, S.; Adams, R.; Costelloe, J. F.; McDonnell, J.

    2014-12-01

    There are competing conceptualisations of heterogeneity in catchment systems. It is often convenient to divide catchments into zones, for example the soil profile, groundwater aquifers (saturated zone), riparian zones, etc. We also often divide flow sources into distinct categories such as surface runoff, interflow and baseflow, implying a few distinct stores of water. In tracer hydrology we typically assume water from such zones has distinct and invariant chemistry that is used to infer the runoff source mixture through conservative mixing model techniques such as End-Member Mixing Analysis (EMMA). An alternative conceptualisation is that catchments consist of a large number of stores with varying residence times. In this case individual stores contribute a variable proportion of flow and may have a temporally varying composition due to processes such as evapo-concentration. Hence they have a variable influence on the hydrochemistry of runoff. In this presentation, examples from two field studies in southern Australia will be presented that examine the relationships between hydrologic and hydrochemical conceptualisations and the relative variation within and between different hydrologic zones. The implications for water quality behaviour will be examined and the additional behavioural complexities associated with interactions between runoff pathways for non-conservative chemical species will be discussed.

  12. Spatio-temporal variability in hydro-chemical characteristics of coastal waters of Salimpur, Chittagong along the Bay of Bengal

    Directory of Open Access Journals (Sweden)

    Avijit Talukder

    2016-04-01

    Full Text Available Diverse seasonal characteristics of hydro-chemical parameters in the coastal zone are significantly related to aquaculture development. In this paper, general water quality condition derived from laboratory analysis from the coastal waters of Salimpur, Chittagong is presented. Samples were collected from onshore and offshore site of two adjacent coastal locations named as North Salimpur (experimental location and South Kattoli (control during a monsoon and a dry season spanning 2013-14. The spatio-temporal variability of studied parameters were found as air temperature 26.5-32.5 ˚C, water temperature 23-33 °C, pH 7.1-7.9, DO 4.29-7.11 mg/L, BOD 1.10-3.25 mg/L, salinity 1.6-21 ppt, EC 3.40-35.68 mS/cm, TDS 2.02-21.99 g/L, TSS 0.62-2.76 g/L, transparency 4.5-14 cm, precipitation 64-1992 mm, NO2-N 1.94-2.58 µg/L, PO4-P 0.45-1.84 µg/L, SiO3-Si 130.46-956.31 µg/L during investigation period. Average values of physicochemical parameters were found to be in compliance with standard guidelines. The ship breaking activities near experimental location possess negative impacts on local geomorphology, freshwater inputs, precipitation and aquatic environment as well. Moreover, wind driven forces, tidal action, wave characteristics and changes in monsoon pattern regulate the coastal processes. This research suggests the importance of regular monitoring to assess present status of water quality and future prospect of aquaculture in the Chittagong coastal zone.

  13. Determination of nitrate pollution sources in the Marano Lagoon (Italy) by using a combined approach of hydrochemical and isotopic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saccon, Pierpaolo; Leis, Albrecht [JOANNEUM RESEARCH Forschungsgesellschaft mbH, Institute for Water, Energy and Sustainability, 8010 Graz (Austria); Marca, Alina; Kaiser, Jan; Campisi, Laura [School of Environmental Sciences, University of East Anglia, NR4 7TJ Norwich (United Kingdom); Boettcher, Michael E.; Escher, Peter [Leibniz Institute for Baltic Sea Research (IOW), Geochemistry and Isotope Geochemistry Group, D-18119 Rostock (Germany); Savarino, Joel; Erbland, Joseph [UJF-Grenoble 1/CNRS-INSU, Laboratoire de Glaciologie et Geophysique de l' Environnement (LGGE) UMR 5183 (France); Eisenhauer, Anton [GEOMAR, Helmholtz Zentrum fuer Ozean Forschung Kiel, Wischhofstr. 1-3, 24148 Kiel (Germany)

    2013-07-01

    Due to increased pollution by nitrate from intensive agricultural and other anthropogenic activities the Marano lagoon (northeast Italy) and part of its catchment area have been investigated, applying a combined approach of hydrochemical and isotopic techniques. Thus, to identify and characterize the potential multiple-sources of nitrate pollution the isotopic compositions of nitrate (δ{sup 15}N, δ{sup 18}O, and Δ{sup 17}O), boron (δ{sup 11}B), water (δ{sup 2}H and δ{sup 18}O), and sulphate (δ{sup 34}S and δ{sup 18}O), as well as the chemical composition of different water types have been determined. In the monitoring program water samples from the lagoon, its tributary rivers, the groundwater upwelling line, groundwater, sewage, and open sea on a quarterly interval from 2009 to 2010 have been collected and analyzed. Coupling isotopic and hydrochemical results indicate that the nitrate load in the lagoon was not only derived from agriculture activities but also from other sources such as urban wastewaters, in situ nitrification, and atmospheric deposition. However, none of the samples showed the isotopic characteristics of synthetic fertilizers. (authors)

  14. Hydrochemical study of Drean–Annaba aquifer system (NE Algeria

    Directory of Open Access Journals (Sweden)

    Sayad Lamine

    2017-09-01

    Full Text Available Water quality is subject to frequent changes in the Drean-Annaba alluvium aquifer. Water-rock interaction can not be the only process that produces the observed modification, but dryness that the country knew during the last two decades has highly contributed to the water quality changes. During this period, irregularities in the distribution of rainfalls, in time and space, have been observed. As a result, a periodicity in hydrochemical changes in water of wells and rivers is noticed. Statistical, the principals components analysis (PCA tools and Tickel diagram have been used to show, through chemical presentation, these effects. The results show, indeed, seasonal changes of water quality for the period 1999-2000. From a cationic point of view, a competition between alkaline and alkaline earths is shown. On the other hand, from an anionic point of view, there is a transition from chlorides to sulphates and may be to bicarbonates. The present work was carried out in a relatively small area and this was useful to show the relationship that existed between dryness and water quality of both the aquifer system and surface water.

  15. Controls on Stormwater Runoff Quality and Quantity in Semi-arid, Urban Catchments

    Science.gov (United States)

    Gallo, E. L.; Brooks, P. D.; Lohse, K. A.

    2009-12-01

    Utilization of recharged urban runoff to complement municipal water supply has gained importance in arid regions where populations and their urban footprint continue to grow, and where water resources are scarce. However, our understanding of how runoff quantity and quality respond to urbanization in arid landscapes is largely incomplete and poses a challenge for water resources management. Here we address the question: What controls the hydrologic and hydrochemical responses of arid urban catchments? We collected water samples and stream stage data from 5 urban catchments of varied land uses (low, medium and high density residential, mixed and commercial land use) in southern Arizona during the summer rainfall seasons of 2007 and 2008. The most homogeneous catchments, as indicated by the index of landscape heterogeneity, were the least and most impervious, while the most heterogeneous sites had mid-range imperviousness. Hydrochemical responses were mixed, did not correlate with imperviousness or vegetation abundance, and were not strongly controlled by land use. Clustering analysis highlight hydrologic and sourcing controls on hydrochemistry, specifically conservative solute transport, land use specific and geologic solute sourcing and atmospheric deposition. Overall, water yields were surprisingly small (< 15%) and increased with imperviousness. Our data show that discharge responses were more sensitive to rainfall magnitude in homogeneous sites. We suggest that imperviousness and rainfall magnitude control water yields; whereas landscape heterogeneity may control a catchment’s sensitivity to generate runoff. The coupling of landscape and hydrology in controlling hydrochemistry is well illustrated by chloride (Cl), a non-reactive hydrologic tracer that was positively correlated with a large number of solutes such as ammonium, dissolved organic carbon, cadmium and zinc. We observed the highest concentrations and coefficients of variation of Cl at least and most

  16. Hydrochemical data from R/V MIKHAIL LOMONSOV and R/V AKADEMIK VERNADSKIY in the Indian Ocean from 16 May 1966 to 01 October 1981 (NODC Accession 0000277)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hydrochemical data were collected from R/V MIKHAIL LOMONSOV and R/V AKADEMIK VERNADSKIY in the Indian Ocean from 16 May 1966 to 01 October 1981. Data were collected...

  17. Isotopic and hydrochemical study of aquifers from Rio Claro District (Sao Paulo State, Brazil)

    International Nuclear Information System (INIS)

    Bonotto, D.N.

    1992-01-01

    An isotopic and hydrochemical study was performed in three aquifers in Rio Claro city area, Sao Paulo State, to establish the chemical facies of the groundwaters and to evaluate the mechanisms of dissolution of the unstable isotope 234 U and 238 U. Mapped groundwater facies were: calcium-bicarbonate for Rio Claro Formation, sodium-nitrate-chloride for fractures in database and sodium-bicarbonate for Tubarao Group. The highest dissolved U contents were measured in groundwaters from the fractured diabase, however, the groundwaters from Tubarao Group showed the highest base-exchange index. Most of the results showed enhancement of 234 U in solution and the highest 234 U/ 238 U activity ratios were measured for groundwaters from Tubarao Group. (author). 33 refs., 5 figs., 1 tab

  18. Towards hydrochemical PUB - stable vs. heterogeneous NO3 and COD signatures across hydrographic structure and size

    Science.gov (United States)

    Ecrepont, Stephane; Cudennec, Christophe; Jaffrezic, Anne; de Lavenne, Alban

    2017-04-01

    Towards hydrochemical PUB - stable vs. heterogeneous NO3 and DOC signatures across hydrographic structure and size Ecrepont, S.1Cudennec, C.1 Jaffrézic, A.1 de Lavenne, A.2 1UMR SAS, Agrocampus Ouest, Rennes, France 2 HBAN, Irstea, Antony, France Intensive agriculture is a major disturbing factor for water quality in Brittany, France. Observations of chemical data from 350 catchments over a 15 year period show that the high variability of hydrochemical dynamics between catchments in relation to geographic characteristics and farming practices, decreases with an increase in the catchment size. A stable signature of nitrate and DOC dynamics does emerge for bigger catchments, and was evidenced statistically. We adapted a modified version of the standard deviation formula to calculate an index on mean inter-annual winter nitrate and dissolved organic carbon concentrations to characterize each catchment. The method was applied to the whole sample of catchments, some of them nested, to investigate variation of our new index across scales and regions. Results show an increasing and non-linear relationship between the criterion and the surface, with threshold effects. The stability of the thresholds across river basins in Brittany, and across seasons and years is explored. This emergence relates to the progressive connection of streams with heterogeneous characteristic chemical signatures into a mixing dominant effect. The better assessment of this relationship opens two major perspectives: i) to define a geomorphology-based PUB (Prediction in Ungauged Basins) approach for hydrochemistry; ii) to identify the most critical sub-catchments for mitigating actions in terms of farming and landscape practices towards water quality recovery.

  19. Isotope and hydrochemical models for evaluation the water loss by evaporation and groundwater flow of dams

    International Nuclear Information System (INIS)

    Santiago, M.F.; Reboucas, A.C.; Frischkorn, H.

    1986-01-01

    Two different approaches are made: an isotope model, based on the observation of the 180/160 ratio of the water, and an hydrochemical model, using the Cl - concentration, are described and applied to determine the evaporation and groundwater flow rates from or to dams. During a period of three years the dams Pereira de Miranda and Caxitore in Pentecostes - Ceara-Brazil (80 Km west of Fortaleza), located in the Precambrian cristalline rock area, were studies. The results show that the models have a good applicability, to estimate the average daily depth of evaporation from free-water surfaces, from nearby porous media or the groundwater inflow or outflow. (author) [pt

  20. Hydrochemical and isotopic study of groundwater impacted by the acid drainage of UrÂnio Mine - Osamu Utsumi, PoÇos de Caldas Plateau (MG), Brazil

    International Nuclear Information System (INIS)

    Alberti, Heber Luiz Caponi

    2017-01-01

    The Osamu Utsumi Mine - MOU, belonging to the Brazilian Nuclear Industries - INB, began in 1977 with pickling activities and remained in operation until 1995. During this period, 94 million tons of rocks were removed, which caused the generation of large wasted rock piles. The intense drainage and precipitation in the study region favored the oxidation and leaching of the wasted rock piles, causing the Acid Drainage of Mine - DAM and generating effluents with low pH and high concentrations of fluoride, aluminum, iron, manganese, sulfate, zinc, uranium and Radio, among others. Currently the MOU is in the process of decommissioning and environmental remediation. The understanding of the hydrogeochemical processes and the behavior of the water flow through different aquifers is extremely important so that the actions of environmental remediation and control of the DAM are really effective. In this sense, in this work, geoprocessing and hydrochemical techniques were used to propose a conceptual hydrogeochemical model in the MOU cavity system and wasted rock pile number 4 - BF4. The geoprocessing techniques allowed to characterize and size the area under study and to integrate information on geology and mineralogy with the hydrochemical data. The hydrochemical studies were based on three groundwater sampling campaigns, using the low flow method in 17 monitoring wells, as well as 3 water reservoirs in the study area. In the collected samples were determined: (1) the main cations and anions for groundwater classification using Piper and Stiff diagrams and multivariate statistical methods (cluster and Principal Component Analysis); (2) the major long half radionuclides and 222 Rn to assess radioactivity and imbalance between them; (3) the stable isotopes of 18 O and 2 H to provide information on the underground flows and water source; (4) the Tritium values found in the samples to estimate the age of the groundwater; (V) the sulfur and oxygen isotopes present in the

  1. Development of a quality management system (QMS) for borehole investigations. (2) Evaluation of applicability of QMS methodology for the hydrochemical dataset

    International Nuclear Information System (INIS)

    Kunimaru, Takanori; Ota, Kunio; Amano, Kenji; Alexander, W. Russell

    2011-01-01

    An appropriate QMS, which is among the first tools required for repository site characterisation, will save on effort by reducing errors and the requirement to resample and reanalyse - but this can only be guaranteed by continuously assessing if the system is truly fit-for-purpose and amending it as necessary based on the practical experience of the end-users on-site. A QA audit of hydrochemical datasets for boreholes HDB-1-11 from Horonobe URL project by JAEA has been carried out by the application of a formal QA analysis which is based on the methodology previously employed for groundwaters during the recent site characterisation programme in Sweden. This methodology has been successfully applied to the groundwaters of the fractured crystalline rocks of the Fennoscandian Shield and has now been adapted and applied to some of the ground- and porewaters of the Horonobe URL area. This paper will present this system in the context of the Japanese national programme and elucidate improvements made during hands-on application of the borehole investigation QMS. Further improvements foreseen for the future will also be discussed with a view of removing inter-operator variability as much as is possible. Only then can confidence by placed in URL project or repository site hydrochemical datasets. (author)

  2. Hydrochemical Characteristics and Evolution of Geothermal Fluids in the Chabu High-Temperature Geothermal System, Southern Tibet

    Directory of Open Access Journals (Sweden)

    X. Wang

    2018-01-01

    Full Text Available This study defines reasonable reservoir temperatures and cooling processes of subsurface geothermal fluids in the Chabu high-temperature geothermal system. This system lies in the south-central part of the Shenzha-Xietongmen hydrothermal active belt and develops an extensive sinter platform with various and intense hydrothermal manifestations. All the geothermal spring samples collected systematically from the sinter platform are divided into three groups by cluster analysis of major elements. Samples of group 1 and group 3 are distributed in the central part and northern periphery of the sinter platform, respectively, while samples of group 2 are scattered in the transitional zone between groups 1 and 3. The hydrochemical characteristics show that the geothermal waters of the research area have generally mixed with shallow cooler waters in reservoirs. The reasonable reservoir temperatures and the mixing processes of the subsurface geothermal fluids could be speculated by combining the hydrochemical characteristics of geothermal springs, calculated results of the chemical geothermometers, and silica-enthalpy mixing models. Contour maps are applied to measured emerging temperatures, mass flow rates, total dissolved solids of spring samples, and reasonable subsurface temperatures. They indicate that the major cooling processes of the subsurface geothermal fluids gradually transform from adiabatic boiling to conduction from the central part to the peripheral belt. The geothermal reservoir temperatures also show an increasing trend. The point with the highest reservoir temperature (256°C appears in the east-central part of the research area, which might be the main up-flow zone. The cooling processes of the subsurface geothermal fluids in the research area can be shown on an enthalpy-chloride plot. The deep parent fluid for the Chabu geothermal field has a Cl− concentration of 290 mg/L and an enthalpy of 1550 J/g (with a water temperature of

  3. Hydrochemistry and hydrogeologic conditions within the Hanford Site upper basalt confined aquifer system

    International Nuclear Information System (INIS)

    Spane, F.A. Jr.; Webber, W.D.

    1995-09-01

    As part of the Hanford Site Ground-Water Surveillance Project, Flow System Characterization Task. Pacific Northwest Laboratory examines the potential for offsite migration of contamination within the upper basalt confined aquifer system for the US Department of Energy (DOE). As part of this activity, groundwater samples were collected over the past 2 years from selected wells completed in the upper Saddle Mountains Basalt. The hydrochemical and isotopic information obtained from these groundwater samples provides hydrologic information concerning the aquifer-flow system. Ideally, when combined with other hydrologic property information, hydrochemical and isotopic data can be used to evaluate the origin and source of groundwater, areal groundwater-flow patterns, residence and groundwater travel time, rock/groundwater reactions, and aquifer intercommunication for the upper basalt confined aquifer system. This report presents the first comprehensive Hanford Site-wide summary of hydrochemical properties for the upper basalt confined aquifer system. This report provides the hydrogeologic characteristics (Section 2.0) and hydrochemical properties (Section 3.0) for groundwater within this system. A detailed description of the range of the identified hydrochemical parameter subgroups for groundwater in the upper basalt confined aquifer system is also presented in Section 3.0. Evidence that is indicative of aquifer contamination/aquifer intercommunication and an assessment of the potential for offsite migration of contaminants in groundwater within the upper basalt aquifer is provided in Section 4.0. The references cited throughout the report are given in Section 5.0. Tables that summarize groundwater sample analysis results for individual test interval/well sites are included in the Appendix

  4. Open source GIS based tools to improve hydrochemical water resources management in EU H2020 FREEWAT platform

    Science.gov (United States)

    Criollo, Rotman; Velasco, Violeta; Vázquez-Suñé, Enric; Nardi, Albert; Marazuela, Miguel A.; Rossetto, Rudy; Borsi, Iacopo; Foglia, Laura; Cannata, Massimiliano; De Filippis, Giovanna

    2017-04-01

    Due to the general increase of water scarcity (Steduto et al., 2012), water quantity and quality must be well known to ensure a proper access to water resources in compliance with local and regional directives. This circumstance can be supported by tools which facilitate process of data management and its analysis. Such analyses have to provide research/professionals, policy makers and users with the ability to improve the management of the water resources with standard regulatory guidelines. Compliance with the established standard regulatory guidelines (with a special focus on requirement deriving from the GWD) should have an effective monitoring, evaluation, and interpretation of a large number of physical and chemical parameters. These amounts of datasets have to be assessed and interpreted: (i) integrating data from different sources and gathered with different data access techniques and formats; (ii) managing data with varying temporal and spatial extent; (iii) integrating groundwater quality information with other relevant information such as further hydrogeological data (Velasco et al., 2014) and pre-processing these data generally for the realization of groundwater models. In this context, the Hydrochemical Analysis Tools, akvaGIS Tools, has been implemented within the H2020 FREEWAT project; which aims to manage water resources by modelling water resource management in an open source GIS platform (QGIS desktop). The main goal of AkvaGIS Tools is to improve water quality analysis through different capabilities to improve the case study conceptual model managing all data related into its geospatial database (implemented in Spatialite) and a set of tools for improving the harmonization, integration, standardization, visualization and interpretation of the hydrochemical data. To achieve that, different commands cover a wide range of methodologies for querying, interpreting, and comparing groundwater quality data and facilitate the pre-processing analysis for

  5. Hydrochemical characteristics of groundwater for domestic and irrigation purposes in Madhuranthakam, Tamil Nadu, India

    Directory of Open Access Journals (Sweden)

    K. Brindha

    2011-12-01

    Full Text Available Hydrochemical study was carried out in Madhuranthakam located near Chennai in Tamil Nadu, India with an objective of understanding the suitability of local groundwater quality for domestic and irrigation purposes. Twenty groundwater samples were collected in February 2002 and analysed for physical and chemical parameters. Groundwater in this area was found to be within the desirable Bureau of Indian Standards and World Health Organisation limits for drinking water. Ca-HCO3 was the dominant groundwater type. Groundwater in this area was assessed for irrigation purposes on the basis of sodium percentage (Na%, magnesium hazard (MH, residual sodium carbonate (RSC, sodium absorption ratio (SAR, permeability index (PI and United States Department of Agriculture (USDA classification. Most of the groundwater samples were suitable for irrigation, except in a few locations (15% based on MH. Overall the groundwater quality was suitable for drinking and domestic purposes and permissible for irrigation activities.

  6. Hydrochemical evaluation of the influences of mining activities on river water chemistry in central northern Mongolia.

    Science.gov (United States)

    Batsaikhan, Bayartungalag; Kwon, Jang-Soon; Kim, Kyoung-Ho; Lee, Young-Joon; Lee, Jeong-Ho; Badarch, Mendbayar; Yun, Seong-Taek

    2017-01-01

    Although metallic mineral resources are most important in the economy of Mongolia, mining activities with improper management may result in the pollution of stream waters, posing a threat to aquatic ecosystems and humans. In this study, aiming to evaluate potential impacts of metallic mining activities on the quality of a transboundary river (Selenge) in central northern Mongolia, we performed hydrochemical investigations of rivers (Tuul, Khangal, Orkhon, Haraa, and Selenge). Hydrochemical analysis of river waters indicates that, while major dissolved ions originate from natural weathering (especially, dissolution of carbonate minerals) within watersheds, they are also influenced by mining activities. The water quality problem arising from very high turbidity is one of the major environmental concerns and is caused by suspended particles (mainly, sediment and soil particles) from diverse erosion processes, including erosion of river banks along the meandering river system, erosion of soils owing to overgrazing by livestock, and erosion by human activities, such as mining and agriculture. In particular, after passing through the Zaamar gold mining area, due to the disturbance of sediments and soils by placer gold mining, the Tuul River water becomes very turbid (up to 742 Nephelometric Turbidity Unit (NTU)). The Zaamar area is also the contamination source of the Tuul and Orkhon rivers by Al, Fe, and Mn, especially during the mining season. The hydrochemistry of the Khangal River is influenced by heavy metal (especially, Mn, Al, Cd, and As)-loaded mine drainage that originates from a huge tailing dam of the Erdenet porphyry Cu-Mo mine, as evidenced by δ 34 S values of dissolved sulfate (0.2 to 3.8 ‰). These two contaminated rivers (Tuul and Khangal) merge into the Orkhon River that flows to the Selenge River near the boundary between Mongolia and Russia and then eventually flows into Lake Baikal. Because water quality problems due to mining can be critical

  7. Idaho Chemical Processing Plant (ICPP) injection well: Operations history and hydrochemical inventory of the waste stream

    International Nuclear Information System (INIS)

    Fromm, J.; McCurry, M.; Hackett, W.; Welhan, J.

    1994-01-01

    Department of Energy (DOE), United States Geological Survey (USGS), and Idaho Chemical Processing Plant (ICPP) documents were searched for information regarding service disposal operations, and the chemical characteristics and volumes of the service waste emplaced in, and above, the Eastern Snake River Plain aquifer (ESRP) from 1953-1992. A summary database has been developed which synthesizes available, but dispersed, information. This assembled data records spatial, volumetric and chemical input patterns which will help establish the initial contaminant water characteristics required in computer modeling, aid in interpreting the monitoring well network hydrochemical information, and contribute to a better understanding of contaminant transport in the aquifer near the ICPP. Gaps and uncertainties in the input record are also identified with respect to time and type. 39 refs., 5 figs., 5 tabs

  8. Hydrochemical characterization and quality evaluation of groundwater in parts of the basement complex area of ekiti, southwestern nigeria

    International Nuclear Information System (INIS)

    Ojo, T.A.; Niyi, T.M.

    2013-01-01

    Well water (88 samples) were collected across various bedrock units in the basement terrain of Ekiti area, Southwestern Nigeria. They were subjected to in-situ physico-chemical measurement and hydrochemical analyses using lC-OES and ion-chromatography methods for cations and anions, respectively. To understand the water quality and utilisation aspects of groundwater, chemical indices like sodium %, sodium adsorption ratio (SAR), Wilcox diagram and salinity diagram were constructed based on the analytical results. The results show pH values ranging between 6.0-7.8 and total hardness (TH) 3.2-508.7 mg/L. Major cations concentrations were in the order of Ca2 >K/sup +/>Na >Mg with average values of 28.5, 26.8, 24.2 and 7.9 mg/L, respectively while that of the anions were HCO >Cl >SO/sub 4/sup 2/ >NO/sub 3/ with average values of 118.7, 54.2, 23.8 and 0.92 mg/L. The main hydrochemical facies being Ca-HCO/sub 3/ waters. The ionic orders of abundance varied in different rocks of the study area. These concentration trends show a low total dissolved solids (130-1544 microS/cm) indicating a low water-rock interaction due to low residence time which is an indication of CO/sub 2/ dominated infiltration recharge with limited migratory history typical of the shallow basement terrain in the study area. Quality assessment revealed a potable groundwater system with chemical parameters within the acceptable limits of the WHO and SON drinking water standards with exception of Fe, Mn and Pb in a couple of locations. Also, the estimated SAR alongside TDS revealed a shallow groundwater system suitable for irrigation purpose. (author)

  9. Application of multivariate statistical analysis and hydrochemical and isotopic investigations for evaluation of groundwater quality and its suitability for drinking and agriculture purposes: case of Oum Ali-Thelepte aquifer, central Tunisia.

    Science.gov (United States)

    Hassen, Imen; Hamzaoui-Azaza, Fadoua; Bouhlila, Rachida

    2016-03-01

    Groundwater plays a dominant role in arid regions; it is among the most available water resources in Tunisia. Located in northwestern Tunisia, Oum Ali-Thelepte is a deep Miocene sedimentary aquifer, where groundwater is the most important source of water supply. The aim of the study is to investigate the hydrochemical processes leading to mineralization and to assess water quality with respect to agriculture and drinking for a better management of groundwater resources. To achieve such objectives, water analysis was carried out on 16 groundwater samples collected during January-February 2014. Stable isotopes and 26 hydrochemical parameters were examined. The interpretation of these analytical data showed that the concentrations of major and trace elements were within the permissible level for human use. The distribution of mineral processes in this aquifer was identified using conventional classification techniques, suggesting that the water facies gradually changes from Ca-HCO3 to Mg-SO4 type and are controlled by water-rock interaction. These results were endorsed using multivariate statistical methods such as principal component analysis and cluster analysis. The sustainability of groundwater for drinking and irrigation was assessed based on the water quality index (WQI) and on Wilcox and Richards's diagrams. This aquifer has been classified as "excellent water" serving good irrigation in the area. As for the stable isotope, the measurements showed that groundwater samples lay between global meteoric water line (GMWL) and LMWL; hence, this arrangement signifies that the recharge of the Oum Ali-Thelepte aquifer is ensured by rainwater infiltration through mountains in the border of the aquifer without evaporation effects.

  10. Hydrogeological and hydrochemical characterization of unconfined aquifer located in the alteration mantle of the Serra Geral Formation, in the Taquari-Antas river basin, northeast of Rio Grande do Sul State

    Directory of Open Access Journals (Sweden)

    Gisele Cemin

    2012-08-01

    Full Text Available This paper presents the hydrogeological and hydrochemical characterization of the unconfined aquifer located in the alteration mantle in the volcanic rocks from Serra Geral Formation, in the northeast region of Rio Grande do Sul State. This aquifer is conditioned by the soil, topography, lithology and climate, being characterized by a saturated layer thinner than 1,7 m, static levels between 0 and 1 m and low flow (<0,5 m3/h. These waters are of calcium or magnesium bicarbonate type, and low alkalinity and electrical conductivity, low calcium, magnesium, sodium, potassium and chloride concentrations, and high iron and manganese concentrations. Additionally, these waters have high concentration of nitrates (mean above 10 mg/L and the presence of total coliforms. These characteristics evidence a quick circulation between the recharging and discharge zones in the aquifer.

  11. Hydrochemical trends for public supply well fields in The Netherlands (1898-2008), natural backgrounds and upscaling to groundwater bodies

    Science.gov (United States)

    Mendizabal, Igor; Baggelaar, Paul K.; Stuyfzand, Pieter J.

    2012-07-01

    SummaryStatistical trend analysis is applied to a 110 years long groundwater quality time series from the national network of public supply well fields (PSWFs) in The Netherlands. Such a groundwater quality monitoring network should be available in many countries, so that approaches and experiences presented here could be of interest world wide. Trendless concentration data series measured in the early years, which should bear the least anthropogenic influences, are selected to quantify the regional natural background concentration levels (NBLs) of groundwater resources at the depth of abstraction. Trends in the period 1960-2005, which contained a more homogeneous data set, are normalized to drinking water standards, mapped in planar view and cross sections, and used to identify the responsible hydrochemical processes. Seven representative trend bundles are defined by aggregation of trends for individual chemical parameters. Trend reversals due to either environmental sanitation measures or well field adaptation measures are identified by comparing significant trends obtained for two different periods within the time series. Natural background levels (NBLs) for individual PSWFs are upscaled to the national groundwater body level (as reported to EU), by aggregating them according to a PSWF typology based on a Hydrochemical System Analysis. This aggregation method groups together PSWFs that deliver waters of the same origin and similar hydrogeochemical environment. PSWFs delivering old groundwaters with a very stable quality are clearly differentiated from PSWFs pumping highly vulnerable aquifers characterized by strongly deteriorating water quality trends. Results are presented on national maps of The Netherlands with NBLs and water quality trends for selected major constituents. A normalized concentration change index (NCC) is defined and mapped to relate the quality difference between a recent survey (in 2008) and calculated NBLs, to the EU drinking water

  12. Hydrochemical and Isotopic Composition of The Water Resources In The Po Delta Plain (northern Italy) and Its Environmental Impact

    Science.gov (United States)

    Rapti Caputo, D.; Martinelli, G.

    Groundwater samples from wells were collected to examine the hydrochemical char- acteristics and isotopic composition of the water resources in the Ferrara area (delta Po plain). Electrical conductivity (EC), pH, total dissolved solid (TDS), temperature of the water were directly measured in the field. Subsequently, in the laboratory, the samples were analysed for the determination of major ions such as Ca, Mg, K, Na, SO4, Cl, NO3 and HCO3. Also, oxygen, deuterium and tritium isotopic composition, of the same samples were analysed for the isotopic characterisation of the waters. Three principal water groups can be distinguished on the basis of the distribution of the values of 18O and 2H. The first group (A), include the waters from the wells that exploit the unsatured shallow aquifer, developing in mainly sandy or sandy-silty lenses. These are large diameter wells, whose depth does not exceed the 7 m, while their piezometric level is at depth varying between 2 and 3 m from the soil surface. The isotopic composition of such wells is strongly affected by meteorological events (local recharge). Indeed, the main supply to the aquifer occurs through infiltration, mainly from rainwaters and, secondly, from the waters contained in the drainage channels. The hydrochemical characteristics of the waters coming from those wells present a very high sulphate concentration (up to 508 mg/l). To the second group (B) belong the waters with an 18O and 2H content lower than the previously described group and varying, respectively, between -9.6 Ferrara plain (Po and Po di Volano rivers). In group C, are the waters of the Po River, where low values can be 1 observed both in oxygen and deuterium contents, with values equal to -9.90 s´ 0.03 and -71.3 s´ 0.9, respectively.

  13. Radiological and hydrochemical study of thermal and fresh groundwater samples of northern Euboea and Sperchios areas, Greece: insights into groundwater natural radioactivity and geology.

    Science.gov (United States)

    Kanellopoulos, C; Mitropoulos, P; Argyraki, A

    2018-04-04

    A radiological and hydrochemical study has been conducted on thermal and fresh groundwater samples of northern Euboea Island and eastern central Greece. Both areas are characterized by complex geology and are renowned since antiquity for their hot springs, that are exploited for therapeutic spa purposes until today. The aim of the study was to combine radiological and hydrochemical data in order to achieve a holistic water quality assessment with insights into the geology of the study areas. All samples were characterized with respect to their major and trace ion and element composition, as well as activity concentrations of 222 Rn, 226 Ra, 228 Ra, 228 Th, and 40 K. The samples demonstrated elevated natural radioactivity and U concentrations, especially in some locations of the Kamena Vourla area, reaching 179 Bq/L 222 Rn, 2.2 Bq/L 226 Ra, 2.9 Bq/L 228 Ra, and 17 μg/L U. The estimated circulation depth of thermal groundwater ranges between 250 m in central Greece and 1240 m in north Euboea study area, whereas the calculated water residence times range between 27 and 555 years. Our data suggest the possible presence of an unknown until know U-rich plutonic rock formation in Kamena Vourla area and immiscibility of the fresh and thermal groundwaters in the studied areas.

  14. Hydrochemical characterization of a mine water geothermal energy resource in NW Spain.

    Science.gov (United States)

    Loredo, C; Ordóñez, A; Garcia-Ordiales, E; Álvarez, R; Roqueñi, N; Cienfuegos, P; Peña, A; Burnside, N M

    2017-01-15

    Abandoned and flooded mine networks provide underground reservoirs of mine water that can be used as a renewable geothermal energy source. A complete hydrochemical characterization of mine water is required to optimally design the geothermal installation, understand the hydraulic behavior of the water in the reservoir and prevent undesired effects such as pipe clogging via mineral precipitation. Water pumped from the Barredo-Figaredo mining reservoir (Asturias, NW Spain), which is currently exploited for geothermal use, has been studied and compared to water from a separate, nearby mountain mine and a river that receives mine water discharge and partially infiltrates into the mine workings. Although the hydrochemistry was altered during the flooding process, the deep mine waters are currently near neutral, net alkaline, high metal waters of Na-HCO 3 type. Isotopic values suggest that mine waters are closely related to modern meteoric water, and likely correspond to rapid infiltration. Suspended and dissolved solids, and particularly iron content, of mine water results in some scaling and partial clogging of heat exchangers, but water temperature is stable (22°C) and increases with depth, so, considering the available flow (>100Ls -1 ), the Barredo-Figaredo mining reservoir represents a sustainable, long-term resource for geothermal use. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Integration of ground-water and vadose-zone geochemistry to investigate hydrochemical evolution

    International Nuclear Information System (INIS)

    Fisher, R.S.; Mullican, W.F.

    1990-01-01

    This paper summarizes the results of an extensive groundwater-sampling program conducted in the Hueco Bolson and Diablo Plateau area of West Texas. The origin, hydrochemical evolution, and age of groundwater in arid lands of Trans-Pecos Texas were investigated by combining mineralogic analyses of soils and aquifer matrix, chemical analyses of readily soluble materials in soils and water extracted from the thick, unsaturated zone, and chemical and isotopic analyses of groundwater from three principal aquifers, the Diablo Plateau, Hueco Bolson, and Rio Grande alluvial aquifers. Repeated groundwater sampling over a 3-year period and quarterly sampling of selected wells revealed no significant short-term chemical or isotopic variability. Groundwater ages range from recent to nearly 28,000 years; the distribution of ages reflects relative permeability (transmissivity) of the aquifers. Most groundwaters evolve from calcium-bicarbonate to sodium-sulfate types because of carbonate and sulfate mineral dissolution coupled with exchange of aqueous calcium and magnesium for sodium on clay minerals. Water in the Rio Grande alluvial aquifer evolved to a sodium-chloride type as a result of extensive evapotranspiration on irrigated fields. The appendices list detailed results of field measurements of temperature, pH, Eh, dissolved oxygen, and major ion concentrations

  16. Evaluation of hydrochemical changes due to intensive aquifer exploitation: case studies from Mexico.

    Science.gov (United States)

    Esteller, M V; Rodríguez, R; Cardona, A; Padilla-Sánchez, L

    2012-09-01

    The impact of intensive aquifer exploitation has been observed in numerous places around the world. Mexico is a representative example of this problem. In 2010, 101 out of the 653 aquifers recognized in the country, showed negative social, economic, and environmental effects related to intensive exploitation. The environmental effects include, among others, groundwater level decline, subsidence, attenuation, and drying up of springs, decreased river flow, and deterioration of water quality. This study aimed at determining the hydrochemical changes produced by intensive aquifer exploitation and highlighting water quality modifications, taking as example the Valle de Toluca, Salamanca, and San Luis Potosi aquifers in Mexico's highlands. There, elements such as fluoride, arsenic, iron, and manganese have been detected, resulting from the introduction of older groundwater with longer residence times and distinctive chemical composition (regional flows). High concentrations of other elements such as chloride, sulfate, nitrate, and vanadium, as well as pathogens, all related to anthropogenic pollution sources (wastewater infiltration, irrigation return flow, and atmospheric pollutants, among others) were also observed. Some of these elements (nitrate, fluoride, arsenic, iron, and manganese) have shown concentrations above Mexican and World Health Organization drinking water standards.

  17. Assessing the Environmental Condition of Minor Rivers in Urban Areas

    Directory of Open Access Journals (Sweden)

    Vladimir Sergeevich Kuznetsov

    2017-11-01

    Full Text Available This article is devoted to the study of water and sediment pollution in the channel of the Neva delta. Spectrophotometry was used to determine the concentration of pollutants in water. In the chemical analysis of the precipitate, atomic absorption spectroscopy and infrared spectroscopy were used. Analysis of the hydrochemical composition and sediment of the Smolenka River showed high concentrations of heavy metals and petroleum products. At the same time, the hydrochemical composition of the Smolenka River is highly unstable, but the concentration of oil products and lead in the sediments indicates the presence of local pollution sources. Based on our findings, we are guided by the restoration of the aquatic environment.

  18. Modelling of the dissolution and reprecipitation of uranium under oxidising conditions in the zone of shallow groundwater circulation.

    Science.gov (United States)

    Dutova, Ekaterina M; Nikitenkov, Aleksei N; Pokrovskiy, Vitaly D; Banks, David; Frengstad, Bjørn S; Parnachev, Valerii P

    2017-11-01

    Generic hydrochemical modelling of a grantoid-groundwater system, using the Russian software "HydroGeo", has been carried out with an emphasis on simulating the accumulation of uranium in the aqueous phase. The baseline model run simulates shallow granitoid aquifers (U content 5 ppm) under conditions broadly representative of southern Norway and southwestern Siberia: i.e. temperature 10 °C, equilibrated with a soil gas partial CO 2 pressure (P CO2 , open system) of 10 -2.5 atm. and a mildly oxidising redox environment (Eh = +50 mV). Modelling indicates that aqueous uranium accumulates in parallel with total dissolved solids (or groundwater mineralisation M - regarded as an indicator of degree of hydrochemical evolution), accumulating most rapidly when M = 550-1000 mg L -1 . Accumulation slows at the onset of saturation and precipitation of secondary uranium minerals at M = c. 1000 mg L -1 (which, under baseline modelling conditions, also corresponds approximately to calcite saturation and transition to Na-HCO 3 hydrofacies). The secondary minerals are typically "black" uranium oxides of mixed oxidation state (e.g. U 3 O 7 and U 4 O 9 ). For rock U content of 5-50 ppm, it is possible to generate a wide variety of aqueous uranium concentrations, up to a maximum of just over 1 mg L -1 , but with typical concentrations of up to 10 μg L -1 for modest degrees of hydrochemical maturity (as indicated by M). These observations correspond extremely well with real groundwater analyses from the Altai-Sayan region of Russia and Norwegian crystalline bedrock aquifers. The timing (with respect to M) and degree of aqueous uranium accumulation are also sensitive to Eh (greater mobilisation at higher Eh), uranium content of rocks (aqueous concentration increases as rock content increases) and P CO2 (low P CO2 favours higher pH, rapid accumulation of aqueous U and earlier saturation with respect to uranium minerals). Copyright © 2017 Elsevier Ltd. All rights

  19. The influence of bedrock hydrogeology on catchment-scale nitrate fate and transport in fractured aquifers.

    Science.gov (United States)

    Orr, Alison; Nitsche, Janka; Archbold, Marie; Deakin, Jenny; Ofterdinger, Ulrich; Flynn, Raymond

    2016-11-01

    Characterising catchment scale biogeochemical processes controlling nitrate fate in groundwater constitutes a fundamental consideration when applying programmes of measures to reduce risks posed by diffuse agricultural pollutants to water quality. Combining hydrochemical analyses with nitrate isotopic data and physical hydrogeological measurements permitted characterisation of biogeochemical processes influencing nitrogen fate and transport in the groundwater in two fractured bedrock aquifers with contrasting hydrogeology but comparable nutrient loads. Hydrochemical and isotopic analyses of groundwater samples collected from moderately fractured, diffusely karstified limestone indicated nitrification controlled dissolved nitrogen fate and delivery to aquatic receptors. By contrast nitrate concentrations in groundwater were considerably lower in a low transmissivity highly lithified sandstone and pyrite-bearing shale unit with patchy subsoil cover. Geophysical and hydrochemical investigations showed shallower intervals contained hydraulically active fractures where denitrification was reflected through lower nitrogen levels and an isotopic enrichment ratio of 1.7 between δ(15)N and δ(18)O. Study findings highlight the influence of bedrock hydrogeological conditions on aqueous nitrogen mobility. Investigation results demonstrate that bedrock conditions need to be considered when implementing catchment management plans to reduce the impact of agricultural practices on the quality of groundwater and baseflow in receiving rivers. Nitrate isotopic signatures in the groundwater of a freely draining catchment underlain by a karstified aquifer and a poorly draining aquifer with a low transmissivity aquifer. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Hydrochemical tracers in the middle Rio Grande Basin, USA: 2. Calibration of a groundwater-flow model

    Science.gov (United States)

    Sanford, Ward E.; Plummer, L. Niel; McAda, Douglas P.; Bexfield, Laura M.; Anderholm, Scott K.

    The calibration of a groundwater model with the aid of hydrochemical data has demonstrated that low recharge rates in the Middle Rio Grande Basin may be responsible for a groundwater trough in the center of the basin and for a substantial amount of Rio Grande water in the regional flow system. Earlier models of the basin had difficulty reproducing these features without any hydrochemical data to constrain the rates and distribution of recharge. The objective of this study was to use the large quantity of available hydrochemical data to help calibrate the model parameters, including the recharge rates. The model was constructed using the US Geological Survey's software MODFLOW, MODPATH, and UCODE, and calibrated using 14C activities and the positions of certain flow zones defined by the hydrochemical data. Parameter estimation was performed using a combination of nonlinear regression techniques and a manual search for the minimum difference between field and simulated observations. The calibrated recharge values were substantially smaller than those used in previous models. Results from a 30,000-year transient simulation suggest that recharge was at a maximum about 20,000 years ago and at a minimum about 10,000 years ago. Le calibrage d'un modèle hydrogéologique avec l'aide de données hydrochimiques a démontré que la recharge relativement faible dans le Grand Bassin du Middle Rio est vraisemblablement responsable d'une dépression des eaux souterraines dans le centre du bassin et de la présence d'une quantité substantielle d'eau du Rio Grande dans l'aquifère du Groupe de Santa Fe. Les modèles antérieurs avaient des difficultés à reproduire ses conclusions sans l'aide de données hydrochimiques pour contraindre les taux et la distribution de la recharge. L'objectif de cette étude était d'utiliser une grande quantité de données hydrochimiques permettant de calibrer les paramètres du modèle, et notamment les taux de recharge. Le modèle a

  1. Development of a groundwater monitoring system at Horonobe Underground Research Center

    International Nuclear Information System (INIS)

    Nanjo, Isao; Amano, Yuki; Iwatsuki, Teruki; Murakami, Hiroaki; Kunimaru, Takanori; Morikawa, Keita; Hosoya, Shinichi

    2012-03-01

    Japan Atomic Energy Agency (JAEA) develops basic investigation techniques for deep geological environment around Underground Research Laboratory (URL) at Horonobe area, Japan. The observation technique of hydrochemical condition in low permeable sedimentary rock around the facility is one of R and D subjects. We report, 1) development of hydrochemical monitoring system to observe water pressure, pH, electric conductivity, dissolved oxygen, redox potential and temperature, 2) hydrochemical observation results around URL under construction. The applicability of the hydrochemical monitoring system is evaluated for low permeable sedimentary rock bearing abundant dissolved gases. The hydrochemical observation during facility construction demonstrates that pH and redox potential of groundwater almost did not changed even at hydraulic disturbed zone (water pressure decreased zone). A CD-ROM is attached as an appendix. (J.P.N.)

  2. Hydrochemical and isotopic properties of the mineralized thermal waters of Kirsehir Province, Turkey

    International Nuclear Information System (INIS)

    Unsal, Nail; Celik, Mehmet; Murathan, Atilla M.

    2003-01-01

    The main objective of this study is to determine the chemical and isotopic properties and reservoir temperature of mineralized thermal waters of Kirsehir region, Turkey. Areas which have been included in this study are Savcih, Karakurt, Terme, Bulamach and Mahmutlu. Mahmutlu and Bulamach waters are mainly of the Na-Cl type, Savcih waters are of the Na-HCO 3 -Cl type and Karakurt and Terme waters are mainly of the Ca-HCO 3 type. The Saturation Index values of the waters have been evaluated and mineralized thermal waters were found to be saturated with respect to the calcite and dolomite minerals but undersaturated with respect to the halite mineral in spite of being NaCl type. The results of hydrochemical and environmental isotope ( 18 O, D, 3 H) analyses show that the waters are of meteoric origin and have varying component of relatively old water. The reservoir temperature of the five areas of thermal manifestations fall between 50 and 100 degC. Highest temperatures of about 100 degC have been estimated for Bulamach and Mahmutlu using various chalcedony geothermometers. Mahmutlu mineralized thermal water has longer residence times and higher reservoir temperature compared to other geothermal areas in Kirsehir Province. (author)

  3. Geological, Hydrogeological and Hydrochemical Field Evidence for Fault Sealing in Marls from Wellenberg, Switzerland

    International Nuclear Information System (INIS)

    Mazurek, Martin

    2001-01-01

    borehole interval is termed the 'channeling fraction', and it varies from close to 1 at shallow levels to almost 0 at a depth of several hundreds of meters. This means that in the uppermost 100 - 200 m, the largest part of all faults present is transmissive, while at depth levels below ca. 500 - 700 m, only a minor part of all faults have a transmissivity in excess of the detection limit of the fluid logging technique. While the fault network is very dense even at greater depth, its permeability is very low, and this is attributed to an efficient self-sealing mechanism of the faults. The systematic increase of hydraulic conductivity towards shallower levels, which is identifiable in all boreholes drilled to date, is attributed to the decrease of normal stress acting on the fault planes. As the region has been uplifting, the progressive exhumation of originally deep-seated faults results in an increase of hydraulic conductivity. Due to the small hydraulic conductivities, all hydraulic tests in the deeper parts of the boreholes characterize only the immediate surroundings of the boreholes. Constraints regarding the nature of the hydraulic regime on a large scale can be derived from 1) hydrochemical evidence and 2) observed head distributions: 1) Pore fluids residing in the present-day fracture and matrix porosity at larger depth consist of methane-saturated Na-Cl water with minute amounts of free methane gas which occurs in druses. Their chemical and isotopic compositions are very similar to those of metamorphic fluids observed in fluid inclusions, suggesting a common origin. Post-metamorphic admixtures of externally derived waters cannot be identified, and it is suggested that present-day Na-Cl groundwaters that occur in the central parts of the marl have resided in the formation since the time of metamorphism some 20 Ma b.p. The only major change in the fluid composition has been the outgassing of methane from the formation, most probably by diffusion. 2) The

  4. Hydrochemical and isotopic properties of the groundwater in the middle part of the Tulian river watershed, Puerto Cortes, Honduras

    International Nuclear Information System (INIS)

    Contreras, Tirza C.; Vargas, Ingrid; Badilla, Elena

    2012-01-01

    The hydrochemical and isotopic properties of 11 springs are identified, including one thermal spring, in Tulian watershed, located in the city of Puerto Cortes, Cortes, Honduras. The relation in the water between the concentrations of the environmental stable isotopes, deuterium (2 H ) and oxygen - 18 (1 8O ), has been similar to the relation in global meteoric water, indicating that the water has a meteoric origin. Evaluation of the geochemical characteristics of the water reveals that these springs belong to the same hydrogeological system, which comprises a fractured schist and gneiss of the Esquistos Cacaguapa formation. The water of the evaluated springs has been mainly sodium bicarbonate and calcium bicarbonate. The isotopic contents have showed without a variation of δ 18 O as would be expected in the hot spring. (author) [es

  5. Assessment of Long-Term Evolution of Groundwater Hydrochemical Characteristics Using Multiple Approaches: A Case Study in Cangzhou, Northern China

    Directory of Open Access Journals (Sweden)

    Wei Li

    2015-03-01

    Full Text Available Water shortage is severe in the North China Plain (NCP. In addition to a deficiency of water resources, deterioration of groundwater quality should be of great concern. In this study, hydrogeological analysis was conducted in combination with principal component analysis, correlation analysis and the co-kriging method to identify factors controlling the content of major ions and total dissolved solids (TDS in areal shallow and deep groundwater and to assess groundwater evolution in Cangzhou, China. The results suggested that groundwater quality degradation occurred and developed in the study area, as indicated by increasing concentrations of major ions, TDS and hardness in both shallow and deep groundwater. In shallow groundwater, whose hydrochemical water types changed from HCO3–Ca.Na.Mg and HCO3.Cl–Na in the west (Zone II to Cl.SO4–Na and Cl–Na in the east (Zone III. Areas with TDS concentrations between 1500 and 2000 mg/L occupied 79.76% of the total in the 1980s, while areas with a TDS concentration ranging from 2500 to 3000 mg/L comprised 59.11% of the total in the 2010s. In deep groundwater, the area with TDS over 1000 mg/L expanded from 5366.39 km2 in the 1960s to 7183.52 km2 in the 2010s. Natural processes (water-rock interactions and anthropogenic activities (groundwater exploitation were the dominant factors controlling the major ions’ content in local groundwater. Dissolution of dolomite, calcite, feldspar and gypsum were the primary sources of major ions in groundwater, and the ion exchange reaction had a strong effect on the cation content, especially for deep groundwater.

  6. Laser induced sonofusion: A new road toward thermonuclear reactions

    Energy Technology Data Exchange (ETDEWEB)

    Sadighi-Bonabi, Rasoul, E-mail: Sadighi@sharif.ir [Sharif University of Technology, P.O. Box 11365-91, Tehran (Iran, Islamic Republic of); Gheshlaghi, Maryam [Payame noor University, P.O. Box 19395-3697, Tehran (Iran, Islamic Republic of); Laser and optics research school, Nuclear Science and Technology Research Institute (NSTRL), P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of)

    2016-03-15

    The Possibility of the laser assisted sonofusion is studied via single bubble sonoluminescence (SBSL) in Deuterated acetone (C{sub 3}D{sub 6}O) using quasi-adiabatic and hydro-chemical simulations at the ambient temperatures of 0 and −28.5 °C. The interior temperature of the produced bubbles in Deuterated acetone is 1.6 × 10{sup 6} K in hydro-chemical model and it is reached up to 1.9 × 10{sup 6} K in the laser induced SBSL bubbles. Under these circumstances, temperature up to 10{sup 7} K can be produced in the center of the bubble in which the thermonuclear D-D fusion reactions are promising under the controlled conditions.

  7. Hydrochemical investigations in characterizing the unsaturated zone at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Yang, I.C.; Rattray, G.W.; Ferarese, J.S.; Yu, P.; Ryan, J.N.

    1998-01-01

    Hydrochemical and isotopic investigations of ground water at Yucca Mountain, Nevada, site of a potential permanent national nuclear-waste repository, demonstrate that younger rocks are dominated by calcium-sulfate or calcium-chloride water and that older rocks contain sodium-carbonate or sodium-bicarbonate water. Furthermore, unsaturated-zone pore water has significantly larger concentrations of major ions and dissolved solids than does the saturated-zone water. Recharge of perched or saturated-zone water, therefore, requires rapid flow through fractures or permeable regions in the unsaturated zone to avoid mixing with the chemically concentrated water in the unsaturated zone. This conceptual model is consistent with observations of rapidly moved post-bomb (post-1954) tritium and chlorine-36 in the deep unsaturated zone at Yucca Mountain. Presence of post-bomb tritium in matrix water away from fracture zones further indicates that parts of the fast-flow water that moves through fractures have been diverted laterally into nonwelded units. Experimental data show that different lithologic units require specific water-extraction methods for stable-isotope analyses of hydrogen and oxygen to ensure accurate characterization. Vacuum-distillation and compression-extraction methods both can yield accurate data but must be used with specific lithologies. Column experiments demonstrate that percolating water can exchange with pore water of the core as well as water held in zeolite minerals in the core. Exchange rates range from days to months. Pore-water samples from core, therefore, reflect the most recently infiltrated water but do not reflect percolating water of the distant past

  8. 42 CFR 482.42 - Condition of participation: Infection control.

    Science.gov (United States)

    2010-10-01

    ... Hospital Functions § 482.42 Condition of participation: Infection control. The hospital must provide a... be an active program for the prevention, control, and investigation of infections and communicable... 42 Public Health 5 2010-10-01 2010-10-01 false Condition of participation: Infection control. 482...

  9. Nitrate Pollution and Preliminary Source Identification of Surface Water in a Semi-Arid River Basin, Using Isotopic and Hydrochemical Approaches

    Directory of Open Access Journals (Sweden)

    Ying Xue

    2016-08-01

    Full Text Available Nitrate contamination in rivers has raised widespread concern in the world, particularly in arid/semi-arid river basins lacking qualified water. Understanding the nitrate pollution levels and sources is critical to control the nitrogen input and promote a more sustainable water management in those basins. Water samples were collected from a typical semi-arid river basin, the Weihe River watershed, China, in October 2014. Hydrochemical assessment and nitrogen isotopic measurement were used to determine the level of nitrogen compounds and identify the sources of nitrate contamination. Approximately 32.4% of the water samples exceeded the World Health Organization (WHO drinking water standard for NO3−-N. Nitrate pollution in the main stream of the Weihe River was obviously much more serious than in the tributaries. The δ15N-NO3− of water samples ranged from +8.3‰ to +27.0‰. No significant effect of denitrification on the shift in nitrogen isotopic values in surface water was observed by high dissolved oxygen (DO values and linear relationship diagram between NO3−-N and δ15N-NO3−, except in the Weihe River in Huayin County and Shitou River. Analyses of hydrochemistry and isotopic compositions indicate that domestic sewage and agricultural activities are the main sources of nitrate in the river.

  10. An Automatic Control System for Conditioning 30 GHz Accelerating Structures

    CERN Document Server

    Dubrovskiy, A

    2008-01-01

    A software application programme has been developed to allow fast and automatic high-gradient conditioning of accelerating structures at 30 GHz in CTF3. The specificity of the application is the ability to control the high-power electron beam which produces the 30 GHz RF power used to condition the accelerating structures. The programme permits operation round the clock with minimum manpower requirements. In this paper the fast control system, machine control system, logging system, graphical user control interface and logging data visualization are described. An outline of the conditioning control system itself and of the feedback controlling peak power and pulse length is given. The software allows different types of conditioning strategies to be programmed

  11. Hydrochemical evaluation of groundwater quality in the Çavuşçayı basin, Sungurlu-Çorum, Turkey

    Science.gov (United States)

    Çelik, Mehmet; Yıldırım, Turgut

    2006-06-01

    The purpose of this study is to investigate the quality and usage possibility of groundwater in the Çavuşçayı basin and suggest the best water structure for the groundwater use. Results from hydrochemical analyses reveal that groundwater is mostly affected by salty (Na+ Cl-) waters of the Incik Formation and brackish (Ca2+, Mg2+ SO{4/2-}) waters of the Bayındır Formation. The Alibaba saltpan discharged (2 l/s) from the Incik Formation is used for salt production. In the basin, salinity risk increases with depth and along the groundwater flow direction. Therefore, shallow water and trenches opened in the alluvium aquifer at the east of the basin were determined to yield suitable water with no Na+ and Cl- contamination. Following the heavy rainy period, waters of less salinity and conductivity are possibly used for agriculture.

  12. Hydrochemical assessment of groundwater used for irrigation in Rumphi and Karonga districts, Northern Malawi

    Science.gov (United States)

    Wanda, Elijah M. M.; Gulula, Lewis C.; Phiri, Ambrose

    Irrigation water quality is an essential component of sustainable agriculture. Irrigation water quality concerns have often been neglected over concerns of quantity in most irrigation projects in Malawi. In this study, a hydrochemical assessment of groundwater was carried out to characterize, classify groundwater and evaluate its suitability for irrigation use in Karonga and Rumphi districts, Northern Malawi. Groundwater samples were collected during wet (January-April 2011) and dry (July-September 2011) seasons from 107 shallow wells and boreholes drilled for rural water supply using standard sampling procedures. The water samples were analysed for pH, major ions, total dissolved solids and electrical conductivity (EC), using standard methods. Multivariate chemometric (such as Kruskal Wallis test), hydrographical methods (i.e. Piper diagram) and PHREEQC geochemical modelling program were used to characterise the groundwater quality. Electrical conductivity, percentage sodium ion (% Na+), residual sodium carbonate (RSC), total dissolved solids (TDS), sodium adsorption ratio (SAR), Kelly’s ratio (KR) and permeability index (PI) were used to evaluate the suitability of water for irrigation. It was established that groundwater is neutral to alkaline and mostly freshwater (TDS management is suggested for sustainable development of the water resources for better plant growth, long-term as well as maintaining human health in the study area.

  13. MODELS OF AIR TRAFFIC CONTROLLERS ERRORS PREVENTION IN TERMINAL CONTROL AREAS UNDER UNCERTAINTY CONDITIONS

    Directory of Open Access Journals (Sweden)

    Volodymyr Kharchenko

    2017-03-01

    Full Text Available Purpose: the aim of this study is to research applied models of air traffic controllers’ errors prevention in terminal control areas (TMA under uncertainty conditions. In this work the theoretical framework descripting safety events and errors of air traffic controllers connected with the operations in TMA is proposed. Methods: optimisation of terminal control area formal description based on the Threat and Error management model and the TMA network model of air traffic flows. Results: the human factors variables associated with safety events in work of air traffic controllers under uncertainty conditions were obtained. The Threat and Error management model application principles to air traffic controller operations and the TMA network model of air traffic flows were proposed. Discussion: Information processing context for preventing air traffic controller errors, examples of threats in work of air traffic controllers, which are relevant for TMA operations under uncertainty conditions.

  14. Assessment of watershed scale nitrogen cycling and dynamics by hydrochemical modeling

    Science.gov (United States)

    Onishi, T.; Hiramatsu, K.; Somura, H.

    2017-12-01

    Nitrogen cycling in terrestrial areas is affecting water quality and ecosystem of aquatic area such as lakes and oceans through rivers. Owing to the intensive researches on nitrogen cycling in each different type of ecosystem, we acquired rich knowledge on nitrogen cycling of each ecosystem. On the other hand, since watershed are composed of many different kinds of ecosystems, nitrogen cycling in a watershed as a complex of these ecosystems is not well quantified. Thus, comprehensive understanding of nitrogen cycling of watersheds by modelling efforts are required. In this study, we attempted to construct hydrochemical model of the Ise Bay watershed to reproduce discharge, TN, and NO3 concentration. The model is based on SWAT (Soil and Water Assessment Tools) model. As anthropogenic impacts related to both hydrological cycling and nitrogen cycling, agricultural water intake/drainage, and domestic water intake/drainage were considered. In addition, fertilizer input to agricultural lands were also considered. Calibration period and validation period are 2004-2006, and 2007-2009, respectively. As a result of calibration using 2000 times LCS (Latin Cubic Sampling) method, discharge of rivers were reproduced fairly well with NS of 0.6-0.8. In contrast, the calibration result of TN and NO3 concentration tended to show overestimate values in spite of considering parameter uncertainties. This implies that unimplemented denitrification processes in the model. Through exploring the results, it is indicated that riparian areas, and agricultural drainages might be important spots for denitrification. Based on the result, we also attempted to evaluate the impact of climate change on nitrogen cycling. Though it is fully explored, this result will also be reported.

  15. Hydrochemical and isotopic characteristics of estuarial seawater and river water of Bailanghe in Laizhou Bay, China

    Science.gov (United States)

    Yang, Qiaofeng; Xu, Suning; Wang, Ruijiu; Li, Wenpeng; Wang, Zhiyi; Mei, Junjun; Ding, Zhilei; Yang, Peijie; Yu, Liangju; Lv, Tieying; Bai, Gang; Kang, Wei

    2016-04-01

    In the study of seawater intrusion, seawater is usually taken as an end-member that mixes with other source(s). However, compared to standard seawater, the coastal seawater particularly that near the estuary, can be strongly influenced by the rivers into the sea and by coastal human activities. Their composition can be thus continuously changed and redistributed with space and time. Therefore, before investigating seawater intrusion in a certain area, it is essentially important to determine the features of the estuarine seawater (e.g. the mixture percentage between standard seawater and river water). In this study, we aimed to gain a clear situation of the seawater intrusion in Laizhou Bay, Southern Bohai, China. The issue aforementioned was investigated by comparing the stable isotopic and hydrochemical composition of the marine and river water collected in this area. Samples investigated include 5 surface water samples collected at the downstream of the Bailanghe and 7 seawater samples near the estuary of Laizhou Bay. Inert tracers (δD, δ18O, Cl, Br) and reaction tracers (Na, Mg, SO4, HCO3, Ca, NO3) are particularly analyzed. The major results are as follows: 1) All the river water samples fall below the Global Meteoric Water Line in the δD - δ18O diagram, reflecting evaporation of the upstream reservoir water. The seawater samples fall on the mixing line of standard seawater and the river water in the stable isotopic diagram. 2) The Cl-δ18O diagram indicates widespread dissolution of evaporate into the river, while high concentration of Ca and HCO3-, as well as the SO42- - Cl relation of the river water samples reflect the dissolution of CO2 , carbonate and sulfate in the atmosphere and on the ground. 3) The Br/Cl ratios of seawater samples are closed to the marine ratios. This together with the plots of major ions vs. Cl suggest that the seawater samples are originated from the mixture of standard seawater and river water. Therefore, when referring to the

  16. A robust model predictive control strategy for improving the control performance of air-conditioning systems

    International Nuclear Information System (INIS)

    Huang Gongsheng; Wang Shengwei; Xu Xinhua

    2009-01-01

    This paper presents a robust model predictive control strategy for improving the supply air temperature control of air-handling units by dealing with the associated uncertainties and constraints directly. This strategy uses a first-order plus time-delay model with uncertain time-delay and system gain to describe air-conditioning process of an air-handling unit usually operating at various weather conditions. The uncertainties of the time-delay and system gain, which imply the nonlinearities and the variable dynamic characteristics, are formulated using an uncertainty polytope. Based on this uncertainty formulation, an offline LMI-based robust model predictive control algorithm is employed to design a robust controller for air-handling units which can guarantee a good robustness subject to uncertainties and constraints. The proposed robust strategy is evaluated in a dynamic simulation environment of a variable air volume air-conditioning system in various operation conditions by comparing with a conventional PI control strategy. The robustness analysis of both strategies under different weather conditions is also presented.

  17. Modeling validation and control analysis for controlled temperature and humidity of air conditioning system.

    Science.gov (United States)

    Lee, Jing-Nang; Lin, Tsung-Min; Chen, Chien-Chih

    2014-01-01

    This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14 °C, 0006 kg(w)/kg(da) in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system.

  18. Modeling Validation and Control Analysis for Controlled Temperature and Humidity of Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Jing-Nang Lee

    2014-01-01

    Full Text Available This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14°C, 0006 kgw/kgda in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system.

  19. Sufficient Controllability Condition for Affine Systems with Two-Dimensional Control and Two-Dimensional Zero Dynamics

    Directory of Open Access Journals (Sweden)

    D. A. Fetisov

    2015-01-01

    Full Text Available The controllability conditions are well known if we speak about linear stationary systems: a linear stationary system is controllable if and only if the dimension of the state vector is equal to the rank of the controllability matrix. The concept of the controllability matrix is extended to affine systems, but relations between affine systems controllability and properties of this matrix are more complicated. Various controllability conditions are set for affine systems, but they deal as usual either with systems of some special form or with controllability in some small neighborhood of the concerned point. An affine system is known to be controllable if the system is equivalent to a system of a canonical form, which is defined and regular in the whole space of states. In this case, the system is said to be feedback linearizable in the space of states. However there are examples, which illustrate that a system can be controllable even if it is not feedback linearizable in any open subset in the space of states. In this article we deal with such systems.Affine systems with two-dimensional control are considered. The system in question is assumed to be equivalent to a system of a quasicanonical form with two-dimensional zero dynamics which is defined and regular in the whole space of states. Therefore the controllability of the original system is equivalent to the controllability of the received system of a quasicanonical form. In this article the sufficient condition for an available solution of the terminal problem is proven for systems of a quasicanonical form with two-dimensional control and two-dimensional zero dynamics. The condition is valid in the case of an arbitrary time interval and arbitrary initial and finite states of the system. Therefore the controllability condition is set for systems of a quasicanonical form with two-dimensional control and two-dimensional zero dynamics. An example is given which illustrates how the proved

  20. A preliminary analysis and assessment of hydrogeological conditions for in-situ leach mining of sandstone-type uranium deposit in northern Ordos basin

    International Nuclear Information System (INIS)

    Chen Fazheng; Zhao Jinfeng; Chang Baocheng; Gao Junyi

    2006-01-01

    A systematic analysis and assessment on hydrogeologic condition, the lithology and hydrogeologic structure of ore-hosting aquitfers, hydrodynamic condition, hydrochemical characteristics at a sandstone-type uranium deposit in northern Ordos basin is made in this paper. It has been concluded, that hydrogeologic condition in the study area is favorable, meeting the requirements for in-situ leach mining of the deposit. Aimed at the low artesian pressure head and low water output and based on the results of pumping-injection tests which led to the significant increase of water output, a technical scheme of pressured water injection has been proposed to artificially raise the artesian pressure head and increase the output of groundwater to satisfy the requirements of in-situ leach mining. (authors)

  1. Assessment of deep geological environment condition

    International Nuclear Information System (INIS)

    Bae, Dae Seok; Han, Kyung Won; Joen, Kwan Sik

    2003-05-01

    The main tasks of geoscientific study in the 2nd stage was characterized focusing mainly on a near-field condition of deep geologic environment, and aimed to generate the geologic input data for a Korean reference disposal system for high level radioactive wastes and to establish site characterization methodology, including neotectonic features, fracture systems and mechanical properties of plutonic rocks, and hydrogeochemical characteristics. The preliminary assessment of neotectonics in the Korean peninsula was performed on the basis of seismicity recorded, Quarternary faults investigated, uplift characteristics studied on limited areas, distribution of the major regional faults and their characteristics. The local fracture system was studied in detail from the data obtained from deep boreholes in granitic terrain. Through this deep drilling project, the geometrical and hydraulic properties of different fracture sets are statistically analysed on a block scale. The mechanical properties of intact rocks were evaluated from the core samples by laboratory testing and the in-situ stress conditions were estimated by a hydro fracturing test in the boreholes. The hydrogeochemical conditions in the deep boreholes were characterized based on hydrochemical composition and isotopic signatures and were attempted to assess the interrelation with a major fracture system. The residence time of deep groundwater was estimated by C-14 dating. For the travel time of groundwater between the boreholes, the methodology and equipment for tracer test were established

  2. Behavior of uranium isotopes along a tidal cycle in a study affected by acid mine drainage; Comportamiento de los isotopos de uranio a lo largo de un ciclo mareal en un estuario afectado por denaje acido de minas

    Energy Technology Data Exchange (ETDEWEB)

    Hierro, A.; Martin, J. e.; Olias, M.; Garcia, C.; Bolivar, J. P.

    2013-07-01

    The Tinto and Odiel rivers converge in an estuarine system known as the Ria de Huelva, which is an ecosystem of great interest, conditioned by hydrochemical facts. The main objective of this study was to analyze the behavior of uranium isotopes in the waters of the Red River estuary in a tidal cycle under hydrochemical conditions of high gradients of salinity and pH generated by the acidic waters of the Rio Tinto and seawater. (Author)

  3. Identification of Hydrochemical Function and Behavior of the Houzhai Karst Basin, Guizhou Province, Southwestern China

    Directory of Open Access Journals (Sweden)

    Xian Li

    2018-01-01

    Full Text Available Due to the difference of geomorphology and the development of fractures, the hydrochemical function and behavior appear to be complex. Variations of karst water conductivity can reflect the contribution of different runoff sources and thus indirectly reflect the development characteristics of conduits and fractures. Taking Houzhai karst system (southwestern China as a case study, the frequency distribution curves of karst water conductivity were decomposed by Gaussian Mixture Analysis to identify the runoff components of different karst landform. The dominant runoff types had been distinguished, and the relative contribution of the different water types had been investigated. The results showed that the karst flow types were slope flow, rapid fracture flow, and slow fracture flow. Rapid fracture flow was the major recharge type of Houzhai karst water system. Slow fracture flow in the downstream area accounted for a larger proportion than that of the upstream area. The relative contribution of the different runoff components showed that the upstream area was a rapid flow area of conduit structure with low storage capacity, the downstream area was an aquifer spatial structure of netted fissure conduit with high storage capacity, and the midstream area was a transitional zone between the upstream and downstream area.

  4. A safety control device for detecting undesirable conditions

    Energy Technology Data Exchange (ETDEWEB)

    1974-09-26

    The invention relates to safety control devices. It deals with a device adapted to transmit a warning signal and to the detection of an undesirable condition in an associated apparatus, said device comprising switching means comprising transistors mounted in a reaction path, feeding means for opening the switching means whenever an undesirable condition has been detected by sensors, whereby an oscillator is caused to stop oscillating, and an outlet device controlled by the oscillator stoppage. This can be applied to the supervision of nuclear reactor.

  5. Seasonal variation of nutrients and hydrological conditions in the State Marine Park of Laje de Santos (SMPLS and adjacent continental shelf areas (South Atlantic Ocean - Brazil

    Directory of Open Access Journals (Sweden)

    Elisabete de Santis Braga

    Full Text Available Abstract Marine parks constitute important areas for the conservation of marine life and the genetic heritage around the world. The creation of such marine parks must be accompanied by careful measures to guarantee the coexistence of natural biota and human activities in these systems. The State Marine Park of Laje de Santos (SMPLS is so close to an industrial pole and urban area that its creation and maintenance is an example for humanity. However, no program has yet been installed for the monitoring of its biotic and abiotic water parameters. Thus, the objective of this study is to provide hydrological and hydrochemical parameters with emphasis on dissolved nutrients to establish a starting point for the monitoring of these waters. The presence of the South Atlantic Central Water (SACW in the marine park during the spring and summer sampling periods was evidenced by the observation of low temperatures ( 7.00 µmol L-1, while the concentration of N-ammonium (maximum 9.86 µmol L-1 demonstrated a rapid regeneration of the organic matter, mainly in the euphotic zone. Analysis of the data from summer periods revealed an annual difference, showing January 2014 to be drier than January 2015, which influenced the availability of some nutrients and the standard distribution of hydrochemical parameters in this region. The results of the distribution of hydrochemical parameters in the marine park confirms the preserved conditions of the seawater around the Laje de Santos, demonstrated by the excellent water quality, concluding the need to implant monitoring actions based on these reference data to preserve this important reserve of marine life.

  6. Hydrochemical investigation and status of geochemical modeling of groundwater evolution at the Kamaishi in-situ tests site, Japan

    International Nuclear Information System (INIS)

    Sasamoto, Hiroshi; Yui, Mikazu; Arthur, Randolph C.

    1999-07-01

    The results of hydrochemical investigations of groundwaters in the Kurihashi granodiorite at JNC's Kamaishi in-situ tests site indicate that these solutions are: meteoric in origin, chemically reducing (at depths greater than a few hundreds meters), relatively young [residence times in the Kurihashi granodiorite generally less than about 40 years, but groundwaters older than several thousand years BP (before present) are also indicated by preliminary carbon-14 dating of samples obtained from the KH-1 borehole], Ca-HCO 3 type solutions near the surface, changing to Na-HCO 3 type groundwaters with increasing depth. The evolution of groundwater compositions in the Kurihashi granodiorite is modeled assuming local equilibrium for selected mineral-fluid reactions, taking into account the rainwater origin of these solutions. Results suggest it is possible to interpret approximately the 'real' groundwater chemistry (i.e., pH, Eh, total dissolved concentrations of Si, Na, Ca, K, Al, carbonate and sulfate) in the Kurihashi granodiorite if the following assumptions are adopted: CO 2 concentration in the gas phase contacting pore solutions in the overlying soil zone=10 -2 bar, minerals in the rock zone that control the solubility of respective elements in the groundwater include; chalcedony (Si), albite (Na), kaolinite (Al), calcite (Ca and carbonate), microcline (K) and pyrite (Eh and sulfate). Discussions with international experts suggest a systematic approach utilizing reaction-path models of irreversible water-rock interactions in open systems may be needed to more realistically model groundwater evolution at the Kamaishi test site. Detailed information characterizing certain site properties (e.g., fracture mineralogy) may be required to adequately constrain such models, however. (author)

  7. Measuring Effectiveness of Persuasive Games Using an Informative Control Condition

    Directory of Open Access Journals (Sweden)

    Mara Soekarjo

    2015-06-01

    Full Text Available Research about the effectiveness of persuasive games is still emerging. This article presents a literature review of studies that empirically evaluate the effectiveness of persuasive games. The review concluded that limited empirical evidence is currently available to prove their effectiveness in attitude change. It further revealed that almost no study employed an informative control condition, making it difficult to conclude that the game was more effective than a control condition. Next, in a pretest-posttest design an empirical study tested whether change in attitude was different for people playing the persuasive game "EnerCities" compared to a control condition where participants read a document with highly similar information. No significant differences in increase of attitude or knowledge between participants that played the game and participants in the informative control condition were found. Based on the results of the literature review and the empirical study presented, it hence cannot be concluded that playing a game leads to a greater change in attitude or knowledge acquisition than experiencing conventional media would. Future work should employ designs with proper control conditions and focus on which game features lead to significant effects.

  8. Hydrochemical controls on aragonite versus calcite precipitation in cave dripwaters

    Science.gov (United States)

    Rossi, Carlos; Lozano, Rafael P.

    2016-11-01

    Despite the paleoclimatic relevance of primary calcite to aragonite transitions in stalagmites, the relative role of fluid Mg/Ca ratio, supersaturation and CO32- concentration in controlling such transitions is still incompletely understood. Accordingly, we have monitored the hydrochemistry of 50 drips and 8 pools that are currently precipitating calcite and/or aragonite in El Soplao and Torca Ancha Caves (N. Spain), investigating the mineralogy and geochemistry of the CaCO3 precipitates on the corresponding natural speleothem surfaces. The data reveal that, apart from possible substrate effects, dripwater Mg/Ca is the only obvious control on CaCO3 polymorphism in the studied stalagmites and pools, where calcite- and aragonite-precipitating dripwaters are separated by an initial (i.e. at stalactite tips) Mg/Ca threshold at ≈1.1 mol/mol. Within the analyzed ranges of pH (8.2-8.6), CO32- concentration (1-6 mg/L), supersaturation (SIaragonite: 0.08-1.08; SIcalcite: 0.23-1.24), drip rate (0.2-81 drops/min) and dissolved Zn (6-90 μg/L), we observe no unequivocal influence of these parameters on CaCO3 mineralogy. Despite the almost complete overlapping supersaturations of calcite- and aragonite-precipitating waters, the latter are on average less supersaturated because the waters having Mg/Ca above ∼1.1 have mostly achieved such high ratios by previously precipitating calcite. Both calcite and aragonite precipitated at or near oxygen isotopic equilibrium, and Mg incorporation into calcite was consistent with literature-based predictions, indicating that in the studied cases CaCO3 precipitation was not significantly influenced by strong kinetic effects. In the studied cases, the calcites that precipitate at ∼11 °C from dripwaters with initial Mg/Ca approaching ∼1.1 incorporate ∼5 mol% MgCO3, close to the published value above which calcite solubility exceeds aragonite solubility, suggesting that aragonite precipitation in high-relative-humidity caves is

  9. Coupled hydrogeological and reactive transport modelling of the Simpevarp area (Sweden)

    International Nuclear Information System (INIS)

    Molinero, Jorge; Raposo, Juan R.; Galindez, Juan M.; Arcos, David; Guimera, Jordi

    2008-01-01

    The Simpevarp area is one of the alternative sites being considered for the deep geological disposal of high level radioactive waste in Sweden. In this paper, a coupled regional groundwater flow and reactive solute transport model of the Simpevarp area is presented that integrates current hydrogeological and hydrochemical data of the area. The model simulates the current hydrochemical pattern of the groundwater system in the area. To that aim, a conceptual hydrochemical model was developed in order to represent the dominant chemical processes. Groundwater flow conditions were reproduced by taking into account fluid-density-dependent groundwater flow and regional hydrogeologic boundary conditions. Reactive solute transport calculations were performed on the basis of the velocity field so obtained. The model was calibrated and sensitivity analyses were carried out in order to investigate the effects of heterogeneities of hydraulic conductivity in the subsurface medium. Results provided by the reactive transport model are in good agreement with much of the measured hydrochemical data. This paper emphasizes the appropriateness of the use of reactive solute transport models when water-rock interaction reactions are involved, and demonstrates what powerful tools they are for the interpretation of hydrogeological and hydrochemical data from site geological repository characterization programs, by providing a qualitative framework for data analysis and testing of conceptual assumptions in a process-oriented approach

  10. The influence of bedrock hydrogeology on catchment-scale nitrate fate and transport in fractured aquifers

    Energy Technology Data Exchange (ETDEWEB)

    Orr, Alison [Arup, 50 Ringsend Road, Dublin 4 (Ireland); School of Planning, Architecture and Civil Engineering, Queen' s University Belfast (United Kingdom); Nitsche, Janka [RPS, West Pier Business Campus, Dun Laoghaire, Co. Dublin (Ireland); School of Planning, Architecture and Civil Engineering, Queen' s University Belfast (United Kingdom); Archbold, Marie [School of Planning, Architecture and Civil Engineering, Queen' s University Belfast (United Kingdom); Environmental Protection Agency, Richview, Clonskeagh Road, Dublin 14 (Ireland); Deakin, Jenny [Environmental Protection Agency, Richview, Clonskeagh Road, Dublin 14 (Ireland); Department of Civil, Structural and Environmental Engineering, Trinity College Dublin (Ireland); Ofterdinger, Ulrich; Flynn, Raymond [School of Planning, Architecture and Civil Engineering, Queen' s University Belfast (United Kingdom)

    2016-11-01

    Characterising catchment scale biogeochemical processes controlling nitrate fate in groundwater constitutes a fundamental consideration when applying programmes of measures to reduce risks posed by diffuse agricultural pollutants to water quality. Combining hydrochemical analyses with nitrate isotopic data and physical hydrogeological measurements permitted characterisation of biogeochemical processes influencing nitrogen fate and transport in the groundwater in two fractured bedrock aquifers with contrasting hydrogeology but comparable nutrient loads. Hydrochemical and isotopic analyses of groundwater samples collected from moderately fractured, diffusely karstified limestone indicated nitrification controlled dissolved nitrogen fate and delivery to aquatic receptors. By contrast nitrate concentrations in groundwater were considerably lower in a low transmissivity highly lithified sandstone and pyrite-bearing shale unit with patchy subsoil cover. Geophysical and hydrochemical investigations showed shallower intervals contained hydraulically active fractures where denitrification was reflected through lower nitrogen levels and an isotopic enrichment ratio of 1.7 between δ{sup 15}N and δ{sup 18}O. Study findings highlight the influence of bedrock hydrogeological conditions on aqueous nitrogen mobility. Investigation results demonstrate that bedrock conditions need to be considered when implementing catchment management plans to reduce the impact of agricultural practices on the quality of groundwater and baseflow in receiving rivers. Nitrate isotopic signatures in the groundwater of a freely draining catchment underlain by a karstified aquifer and a poorly draining aquifer with a low transmissivity aquifer. - Graphical abstract: Contrasting nitrate isotope signatures of groundwater in a free draining catchment underlain by a karstified aquifer and a poorly drained catchment underlain by a low transmissivity aquifer. - Highlights: • Comparison of N fate and

  11. Control in chronic condition self-care management

    DEFF Research Database (Denmark)

    Lawn, Sharon; Delany, Toni; Sweet, Linda

    2014-01-01

    of their communication style and the power of their role must improve for client chronic condition self-care management to be achieved. Training on the impacts of control in worker communication and systems where they work must be provided if unbeneficial forms of client dependency are to be overcome and true self......Aim: To examine health worker-client interactions during care planning to understand processes that foster client empowerment and disempowerment. Background: It is unclear how health worker-client exchanges and information sharing through chronic condition care planning currently operate in primary...... health care. Moreover, it is unclear how control in these exchanges either enhances collaborative decision-making, partnership and client empowerment, or works to create client disempowerment and dependency on workers and health services. Design: Critical discourse analysis of qualitative data from...

  12. Hydrochemical evaluation of groundwater in the Blue Nile Basin, eastern Sudan, using conventional and multivariate techniques

    Science.gov (United States)

    Hussein, Mohammed Tahir

    Hydrochemical evaluation of groundwater systems can be carried out using conventional and multivariate techniques, namely cluster, factor analyses and others such as correspondence analysis. The main objective of this study is to investigate the groundwater quality in the Blue Nile basin of eastern Sudan, and to workout a hydrochemical evaluation for the aquifer system. Conventional methods and multivariate techniques were applied to achieve these goals. Two water-bearing layers exist in the study area: the Nubian Sandstone Formation and the Al-Atshan Formation. The Nubian aquifer is recharged mainly from the Blue Nile and Dinder Rivers through lateral subsurface flow and through direct rainfall in outcrop areas. The Al-Atshan aquifer receives water through underground flow from River Rahad and from rainfall infiltration. The prevailing hydrochemical processes are simple dissolution, mixing, partial ion exchange and ion exchange. Limited reverse ion exchange has been witnessed in the Nubian aquifer. Three factors control the overall mineralization and water quality of the Blue Nile Basin. The first factor includes high values of total dissolved solids, electrical conductivity, sodium, potassium, chloride, bicarbonate, sulphate and magnesium. The second factor includes calcium and pH. The third factor is due to fluoride concentration in the groundwater. The study highlights the descriptive capabilities of conventional and multivariate techniques as effective tools in groundwater quality evaluation. Une étude hydrochimique de systèmes aquifères a pu être réalisée au moyen des techniques conventionnelles et multidimensionnelles, telles que les analyses de cluster et factorielles, ainsi que d'autres comme l'analyse des correspondances. Le principal objectif de ce travail est d'étudier la qualité des eaux souterraines du bassin du Nil bleu au Soudan oriental, et de réaliser une évaluation hydrochimique du système aquifère. Des méthodes conventionnelles et

  13. Installation of PMV Operation Program in DDC Controller and Air Conditioning Control Using PMV Directly as Set Point

    Science.gov (United States)

    Haramoto, Ken-Ichi

    In general, air conditioning control in a building is operated mainly by indoor air temperature control. Although the operators of the machine in the building accepted a claim for indoor air temperature presented by the building inhabitants, the indoor conditions have been often too cool or warm. Therefore, in an attempt to create better thermal environments, the author paid attention to the PMV that is a thermal comfort index. And then, the possibility of air conditioning control using the PMV directly as the set point was verified by employing actual equipment in an air conditioning testing room and an office building. Prior to the execution of this control, the operation program of the PMV was installed in a DDC controller for the air conditioning control. And information from indoor sensors and so on was inputted to the controller, and the computed PMV was used as the feedback variable.

  14. Microcomputer control of a residential photovoltaic power conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Bose, B.K.; Steigerwald, R.L.; Szczesny, P.M.

    1984-01-01

    Microcomputer-based control of a residential photovoltaic power conditioning system is described. The microcomputer is responsible for array current feedback control, maximum power tracking control, array safe zone steering control, phase-locked reference wave synthesis, sequencing control, and some diagnostics. The control functions are implemented using Intel 8751 single-chip microcomputer-based hardware and software. The controller has been tested in the laboratory with the prototype power conditioner and shows excellent performance.

  15. Microcomputer control of a residential photovoltaic power conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Bose, B.K.; Steigerwald, R.L.; Szczesny, P.M.

    1985-09-01

    Microcomputer-based control of a residential photovoltaic power conditioning system is described. The microcomputer is responsible for array current feedback control, maximum power tracking control, array safe zone steering control, phase-locked reference wave synthesis, sequencing control, and some diagnostics. The control functions are implemented using Intel 8751 single-chip microcomputer-based hardware and software. The controller has been tested in the laboratory with the prototype power conditioner and shows excellent performance.

  16. Use of nuclear techniques and hydrochemical analysis to evaluate the impact of tailings dams

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Flaviane M.; Fleming, Peter M.; Fonseca, Flávio H. da R.; Pimenta, Rafael C.; Moreira, Rubens M., E-mail: flaviane@cdtn.br, E-mail: pmf@cdtn.br, E-mail: flavio.fonseca@cdtn.br, E-mail: colombopimenta@gmail.com, E-mail: rubens@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-11-01

    The mining industry is a most important productive segment to country's economy. However, it is important to recognize and monitor the environmental impacts caused by mining, such as dams. They are structures built to store the waste produced by the beneficiation of ores, through chemical and mechanical processes classified as concentrate, crude ore or tailings. Tailings dams are associated with a potential risk of disruption and can therefore cause various images to the environment and population. Seepage flows and transport mechanisms are parameters to indicate the structural integrity. Nuclear technology can be used as a tool to trace these parameters. The objective of this work is to use isotopic techniques and hydrochemical characterization to detect leaks in dams belonging to a mining company. The isotopic techniques are used to measure the concentration of environmental isotopes in dam waters and their mediations, among which deuterium ({sup 2}H) and oxygen-18 ({sup 18}O) are measured. These isotopes will be used as environmental tracers to investigate the presence of infiltrations through the displacement of the water in its flow in the aquifer, since they are constituent of the molecule of water. In parallel, the basic physical chemical parameters and water quality parameters will be measured in-situ to aid in the interpretation of the results of the isotopic analyzes. Thus, it is intended to provide data that can help the environmental agencies to make decisions regarding the decommissioning of the mine. (author)

  17. Hydrochemical and microbiological quality of groundwater in the Merdja area, Tébessa, North-East of Algeria

    Science.gov (United States)

    Fehdi, Chemseddine; Rouabhia, Abdelkader; Mechai, Abdelbasset; Debabza, Manel; Abla, Khalida; Voudouris, Kostas

    2016-03-01

    The aim of this study was to perform a preliminary assessment of the hydrochemical and microbial groundwater quality of the Merdja plain (Tébessa area). Twenty samples of groundwater collected from Bekkaria (Site 1) to Ain Chabro (Site 2) were assessed for their suitability for human consumption. Groundwater from the aquifer in the Merdja area can be divided into two major groups according to geographical locations and chemical compositions. Water in the center part of the study area is characterized by the dominance of chloride, sulfate, sodium, and potassium; whereas waters in the limestone aquifers in the west are dominated by the same cations but have higher concentrations of bicarbonate. Microbiological parameters were determined in 13 groundwater samples collected from the study area. Total coliforms, thermotolerant coliforms, E. coli, Enterococcus spp., Salmonella sp., Staphylococcus spp., and P. aeruginosa were detected in 96.36, 88.18, 100, 47.5, 97.27, 96.7, and 75 % of the groundwater samples, respectively. The pollution of groundwater comes from a variety of sources, Ouadi El Kebir River, including land application of agricultural chemicals and organic wastes, infiltration of irrigation water, septic tanks, and infiltration of effluent from sewage treatment plants, pits, lagoons, and ponds used for storage.

  18. Statistical Classification Of the Environmental Isotopes and the Hydrochemical data in the main Shallow Coastal Aquifer System in North West, Egypt

    International Nuclear Information System (INIS)

    Nada, A.A.; AL-Gamal, S.A.

    1999-01-01

    Multivariate statistical analysis of hydrochemical data and environmental isotopes were used in differentiating ground waters of different types within the quaternary aquifer in the north western coast of Egypt. Three main groups of water types were differentiated, in close agreement with three isotopic water groups, based on field and laboratory studies. The first group includes the sodium bicarbonate water type of meteoric origin (cluster 1 in multivariate analysis and isotopic water group 1) whereas, the second group includes both sodium chloride and sodium sulphate waters.(cluster in multivariate analysis and isotopic group 2). The third group represents ground water of salt water intrusion whose water type is sodium chloride (cluster 111 and isotopic water groups 3) .The data show that salinity ranges from 385 mg/L representing very fresh water to 12260 mg/L representing water contaminated with marine water due to excessive pumping in some Localities.

  19. Experimental analysis of fuzzy controlled energy efficient demand controlled ventilation economizer cycle variable air volume air conditioning system

    Directory of Open Access Journals (Sweden)

    Rajagopalan Parameshwaran

    2008-01-01

    Full Text Available In the quest for energy conservative building design, there is now a great opportunity for a flexible and sophisticated air conditioning system capable of addressing better thermal comfort, indoor air quality, and energy efficiency, that are strongly desired. The variable refrigerant volume air conditioning system provides considerable energy savings, cost effectiveness and reduced space requirements. Applications of intelligent control like fuzzy logic controller, especially adapted to variable air volume air conditioning systems, have drawn more interest in recent years than classical control systems. An experimental analysis was performed to investigate the inherent operational characteristics of the combined variable refrigerant volume and variable air volume air conditioning systems under fixed ventilation, demand controlled ventilation, and combined demand controlled ventilation and economizer cycle techniques for two seasonal conditions. The test results of the variable refrigerant volume and variable air volume air conditioning system for each techniques are presented. The test results infer that the system controlled by fuzzy logic methodology and operated under the CO2 based mechanical ventilation scheme, effectively yields 37% and 56% per day of average energy-saving in summer and winter conditions, respectively. Based on the experimental results, the fuzzy based combined system can be considered to be an alternative energy efficient air conditioning scheme, having significant energy-saving potential compared to the conventional constant air volume air conditioning system.

  20. A diatom functional-based approach to assess changing environmental conditions in temporary depressional wetlands

    CSIR Research Space (South Africa)

    Riato, L

    2017-07-01

    Full Text Available is limited although important for the development of temporary wetland biological assessments. We assessed how diatom life-form and ecological guilds responded to a seasonal hydrological and hydrochemical gradient in three least human-disturbed, temporary...

  1. Experimental Study on Intelligent Control Scheme for Fan Coil Air-Conditioning System

    Directory of Open Access Journals (Sweden)

    Yanfeng Li

    2013-01-01

    Full Text Available An intelligent control scheme for fan coil air-conditioning systems has been put forward in order to overcome the shortcomings of the traditional proportion-integral-derivative (PID control scheme. These shortcomings include the inability of anti-interference and large inertia. An intelligent control test rig of fan coil air-conditioning system has been built, and MATLAB/Simulink dynamics simulation software has been adopted to implement the intelligent control scheme. A software for data exchange has been developed to combine the intelligence control system and the building automation (BA system. Experimental tests have been conducted to investigate the effectiveness of different control schemes including the traditional PID control, fuzzy control, and fuzzy-PID control for fan coil air-conditioning system. The effects of control schemes have been compared and analyzed in robustness, static and dynamic character, and economy. The results have shown that the developed data exchange interface software can induce the intelligent control scheme of the BA system more effectively. Among the proposed control strategies, fuzzy-PID control scheme which has the advantages of both traditional PID and fuzzy schemes is the optimal control scheme for the fan coil air-conditioning system.

  2. A novel capacity controller for a three-evaporator air conditioning (TEAC) system for improved indoor humidity control

    International Nuclear Information System (INIS)

    Yan, Huaxia; Deng, Shiming; Chan, Ming-yin

    2016-01-01

    Highlights: • A novel capacity controller for TEAC systems for improved indoor humidity control is developed. • The novel controller was developed by integrating two previous control algorithms. • Experimental controllability tests were carried out. • Improved control over indoor humidity levels and higher energy efficiency can be achieved. - Abstract: Using a multi-evaporator air conditioning (MEAC) system to correctly control indoor air temperatures only in a multi-room application is already a challenging and difficult task, let alone the control of both indoor air temperature and humidity. This is because in an MEAC system, a number of indoor units are connected to a common condensing unit. Hence, the interferences among operation parameters of different indoor units would make the desired control of an MEAC system hard to realize. Limited capacity control algorithms for MEAC systems have been developed, with most of them focusing only on the control of indoor air temperature, and no previous studies involving control of indoor air humidity using MEAC systems can be identified. In this paper, the development of a novel capacity controller for a three-evaporator air conditioning (TEAC) system for improved indoor air humidity control is reported. The novel controller was developed by integrating two previous control algorithms for a dual-evaporator air conditioning system for temperature control and for a single-evaporator air conditioning system for improved indoor humidity control. Experimental controllability tests were carried out and the controllability test results showed that, with the novel controller, improved control over indoor humidity levels and better energy efficiency for a TEAC system could be obtained as compared to the traditional On–Off controllers extensively used by MEAC systems.

  3. Controllable conditional quantum oscillations and quantum gate operations in superconducting flux qubits

    International Nuclear Information System (INIS)

    Chen Aimin; Cho Samyoung

    2011-01-01

    Conditional quantum oscillations are investigated for quantum gate operations in superconducting flux qubits. We present an effective Hamiltonian which describes a conditional quantum oscillation in two-qubit systems. Rabi-type quantum oscillations are discussed in implementing conditional quantum oscillations to quantum gate operations. Two conditional quantum oscillations depending on the states of control qubit can be synchronized to perform controlled-gate operations by varying system parameters. It is shown that the conditional quantum oscillations with their frequency synchronization make it possible to operate the controlled-NOT and -U gates with a very accurate gate performance rate in interacting qubit systems. Further, this scheme can be applicable to realize a controlled multi-qubit operation in various solid-state qubit systems. (author)

  4. Intelligent energy management control of vehicle air conditioning system coupled with engine

    International Nuclear Information System (INIS)

    Khayyam, Hamid; Abawajy, Jemal; Jazar, Reza N.

    2012-01-01

    Vehicle Air Conditioning (AC) systems consist of an engine powered compressor activated by an electrical clutch. The AC system imposes an extra load to the vehicle's engine increasing the vehicle fuel consumption and emissions. Energy management control of the vehicle air conditioning is a nonlinear dynamic system, influenced by uncertain disturbances. In addition, the vehicle energy management control system interacts with different complex systems, such as engine, air conditioning system, environment, and driver, to deliver fuel consumption improvements. In this paper, we describe the energy management control of vehicle AC system coupled with vehicle engine through an intelligent control design. The Intelligent Energy Management Control (IEMC) system presented in this paper includes an intelligent algorithm which uses five exterior units and three integrated fuzzy controllers to produce desirable internal temperature and air quality, improved fuel consumption, low emission, and smooth driving. The three fuzzy controllers include: (i) a fuzzy cruise controller to adapt vehicle cruise speed via prediction of the road ahead using a Look-Ahead system, (ii) a fuzzy air conditioning controller to produce desirable temperature and air quality inside vehicle cabin room via a road information system, and (iii) a fuzzy engine controller to generate the required engine torque to move the vehicle smoothly on the road. We optimised the integrated operation of the air conditioning and the engine under various driving patterns and performed three simulations. Results show that the proposed IEMC system developed based on Fuzzy Air Conditioning Controller with Look-Ahead (FAC-LA) method is a more efficient controller for vehicle air conditioning system than the previously developed Coordinated Energy Management Systems (CEMS). - Highlights: ► AC interacts: vehicle, environment, driver components, and the interrelationships between them. ► Intelligent AC algorithm which uses

  5. Hydrochemical study of phreatic aquifers in the town of Ambohidrapeto Antananarivo

    International Nuclear Information System (INIS)

    Randriantsivery, J.M.

    2014-01-01

    Most of the population in the urban district of Ambohidrapeto, South of Antananarivo, Madagascar does not have access to safe drinking water provided by the national electricity and water company (JIRAMA), leading them to use traditional dug wells and springs as potential sources of water supplies, although might contain highly contaminated waters. The aim of this study was to assess the pollution level of the shallow ground waters in this area using hydrochemical study. Major ions were the chemical parameters measured using ion chromatography. Twenty water samples were collected in different water points, among which: Antanetibe, Ambodiapanga, Antohetra, Avaratsena and Soamiampita, of which 17 were taken from traditional dug wells and 3 from spring waters. The results showed that the water samples can be classified in four different chemical types : first the magnesian and sodium chloride type (Na-Mg-NO 3 -Cl) for the well water samples PO3, PO7, PO10, PO11, PO12, PO13, PO16, PO17, PO18, PO19, PO20, SA01, SA02 and SA03; second the Na-Mg-NO 3 type for samples of high concentration in nitrate ion NO 3 - (PO2, PO5 and PO9); third the Mg-Na-NO 3 -Cl type for the PO14 well spring samples and finally the Mg-Na-NO 3 type for PO15 with slightly high concentration in nitrate comparing to the sodium type. Besides, a high contamination of nitrate not only in all well water samples but also in all spring water samples was observed. The average value is 190 mg.L -1 , which is four times greater than the WHO admissible value of 50 mg.L -1 . This high contamination by nitrate could be explained by the presence of latrines in the vicinity of the water points, which are usually located at less that 10 m from the excavation. [fr

  6. Modelling and Control of Ionic Electroactive Polymer Actuators under Varying Humidity Conditions

    Directory of Open Access Journals (Sweden)

    S. Sunjai Nakshatharan

    2018-02-01

    Full Text Available In this work, we address the problem of position control of ionic electroactive polymer soft actuators under varying relative humidity conditions. The impact of humidity on the actuation performance of ionic actuators is studied through frequency response and impedance spectroscopy analysis. Considering the uncertain performance of the actuator under varying humidity conditions, an adaptable model using the neural network method is developed. The model uses relative humidity magnitude as one of the model parameters, making it robust to different environmental conditions. Utilizing the model, a closed-loop controller based on the model predictive controller is developed for position control of the actuator. The developed model and controller are experimentally verified and found to be capable of predicting and controlling the actuators with excellent tracking accuracy under relative humidity conditions varying in the range of 10–90%.

  7. Hydrogeochemical Characteristics and Evolution of Hot Springs in Eastern Tibetan Plateau Geothermal Belt, Western China: Insight from Multivariate Statistical Analysis

    Directory of Open Access Journals (Sweden)

    Zheming Shi

    2017-01-01

    Full Text Available The eastern Tibetan Plateau geothermal belt is one of the important medium-high temperature geothermal belts in China. However, less work has been done on the hydrochemical characteristic and its geological origin. Understanding the chemical characteristics and the hydrochemical evolution processes is important in evaluating the geothermal energy potential in this area. In the present study, we discussed the hydrochemical properties and their origins of 39 hot springs located in the eastern Tibetan Plateau geothermal belt (Kangding-Litang-Batang geothermal belt. Cluster analysis and factor analysis are employed to character the hydrochemical properties of hot springs in different fault zones and the possible hydrochemical evolution processes of these hot springs. Our study shows that the hot springs can be divided into three groups based on their locations. The hot springs in the first group mainly originate from the volcanic rock and the springs in the second group originate from the metamorphic rock while the springs in the third group originate from the result of mixture of shallow water. Water-rock interaction, cation exchange, and the water environment are the three dominant factors that control the hydrochemical evolution process in the eastern Tibetan Plateau. These results are also in well agreement with the isotopic and chemical analysis.

  8. The speed control of DC motor under the load condition using PI and PID controllers

    Science.gov (United States)

    Corapsiz, Muhammed Reşit; Kahveci, Hakan

    2017-04-01

    In this study, it was aimed to compare PI (Proportional-Integral) and PID (Proportional-Integral-Derivative) controllers for speed control of Permanent Magnet Direct Current (PMDC) motor under both load and without load. For this purpose, firstly, the mathematical model was obtained from the dynamic equations of the PMDC motor and the obtained mathematical model was transferred to the simulation environment and modeled using Matlab/SIMULINK. Following the modeling process, PI and PID controller structures were formed, respectively. Secondly, after these structures were formed, the PMDC motor was run without any controller. Then, the control of the PMDC motor with no load was provided by using PI and PID controllers. Finally, the PMDC motor were loaded under the constant load (TL = 3 N.m.) for each condition and selected time period (t = 3 s). The obtained result for each control operations was comparatively given by observing effects of loading process on systems. When the obtained results were evaluated for each condition, it was observed that PID controller have the best performance with respect to PI controller.

  9. A Question of Control? Examining the Role of Control Conditions in Experimental Psychopathology using the Example of Cognitive Bias Modification Research.

    Science.gov (United States)

    Blackwell, Simon E; Woud, Marcella L; MacLeod, Colin

    2017-10-26

    While control conditions are vitally important in research, selecting the optimal control condition can be challenging. Problems are likely to arise when the choice of control condition is not tightly guided by the specific question that a given study aims to address. Such problems have become increasingly apparent in experimental psychopathology research investigating the experimental modification of cognitive biases, particularly as the focus of this research has shifted from theoretical questions concerning mechanistic aspects of the association between cognitive bias and emotional vulnerability, to questions that instead concern the clinical efficacy of 'cognitive bias modification' (CBM) procedures. We discuss the kinds of control conditions that have typically been employed in CBM research, illustrating how difficulties can arise when changes in the types of research questions asked are not accompanied by changes in the control conditions employed. Crucially, claims made on the basis of comparing active and control conditions within CBM studies should be restricted to those conclusions allowed by the specific control condition employed. CBM studies aiming to establish clinical utility are likely to require quite different control conditions from CBM studies aiming to illuminate mechanisms. Further, conclusions concerning the clinical utility of CBM interventions cannot necessarily be drawn from studies in which the control condition has been chosen to answer questions concerning mechanisms. Appreciating the need to appropriately alter control conditions in the transition from basic mechanisms-focussed investigations to applied clinical research could greatly facilitate the translational process.

  10. Developed adaptive neuro-fuzzy algorithm to control air conditioning ...

    African Journals Online (AJOL)

    The paper developed artificial intelligence technique adaptive neuro-fuzzy controller for air conditioning systems at different pressures. The first order Sugeno fuzzy inference system was implemented and utilized for modeling and controller design. In addition, the estimation of the heat transfer rate and water mass flow rate ...

  11. Environmental Tritium (3H) and hydrochemical investigations to evaluate groundwater in Varahi and Markandeya river basins, Karnataka, India

    International Nuclear Information System (INIS)

    Ravikumar, P.; Somashekar, R.K.

    2011-01-01

    The present study aimed at assessing the activity of natural radionuclides ( 3 H) and hydrochemical parameters (viz., pH, EC, F - , NO 3 - , Cl - , Ca 2+ , Mg 2+ ) in the groundwater used for domestic and irrigation purposes in the Varahi and Markandeya river basins to understand the levels of hydrochemical parameters in terms of the relative age(s) of the groundwater contained within the study area. The recorded environmental 3 H content in Varahi and Markandeya river basins varied from 1.95 ± 0.25 T.U. to 11.35 ± 0.44 T.U. and 1.49 ± 0.75 T.U. to 9.17 ± 1.13 T.U. respectively. Majority of the samples in Varahi (93.34%) and Markandeya (93.75%) river basins being pre-modern water with modern recharge, significantly influenced by precipitation and river inflowing/sea water intrusion. The EC-Tritium and Tritium-Fluoride plots confirmed the existence of higher total dissolved solids (SEC > 500 μS/cm) and high fluoride (MAC > 1.5 mg/L) in groundwater of Markandeya river basin, attributed to relatively longer residence time of groundwater interacting with rock formations and vice versa in case of Varahi river basin. The tritium-EC and tritium-chloride plots indicated shallow and deep circulating groundwater types in Markandeya river basin and only shallow circulating groundwater type in Varahi river basin. Increasing Mg relative to Ca with decreasing tritium indicated the influence of incongruent dissolution of a dolomite phase. The samples with high nitrate (MAC > 45 mg/L) are waters that are actually mixtures of fresh water (containing very high nitrate, possibly from agricultural fertilizers) and older 'unpolluted' waters (containing low nitrate levels), strongly influenced by surface source. - Research highlights: → It is evident that majority of the samples in Varahi (93.34%) and Markandeya (93.75%) river basins exhibited radioactive decay (1-8 T.U.) having a mixture of pre-modern (viz., old water) water with modern (viz., new water) recharge, significantly

  12. Gain control network conditions in early sensory coding.

    Directory of Open Access Journals (Sweden)

    Eduardo Serrano

    Full Text Available Gain control is essential for the proper function of any sensory system. However, the precise mechanisms for achieving effective gain control in the brain are unknown. Based on our understanding of the existence and strength of connections in the insect olfactory system, we analyze the conditions that lead to controlled gain in a randomly connected network of excitatory and inhibitory neurons. We consider two scenarios for the variation of input into the system. In the first case, the intensity of the sensory input controls the input currents to a fixed proportion of neurons of the excitatory and inhibitory populations. In the second case, increasing intensity of the sensory stimulus will both, recruit an increasing number of neurons that receive input and change the input current that they receive. Using a mean field approximation for the network activity we derive relationships between the parameters of the network that ensure that the overall level of activity of the excitatory population remains unchanged for increasing intensity of the external stimulation. We find that, first, the main parameters that regulate network gain are the probabilities of connections from the inhibitory population to the excitatory population and of the connections within the inhibitory population. Second, we show that strict gain control is not achievable in a random network in the second case, when the input recruits an increasing number of neurons. Finally, we confirm that the gain control conditions derived from the mean field approximation are valid in simulations of firing rate models and Hodgkin-Huxley conductance based models.

  13. Fuzzy logic control of air-conditioning system in residential buildings

    Directory of Open Access Journals (Sweden)

    Abdel-Hamid Attia

    2015-09-01

    Full Text Available There has been a rising concern in reducing the energy consumption in building. Heating ventilation and air condition system is the biggest consumer of energy in building. In this study, fuzzy logic control of the air conditioning system of building for efficient energy operation and comfortable environment is investigated. A theoretical model of the fan coil unit (FCU and the heat transfer between air and coolant fluid is derived. The controlled variables are the room temperature and relative humidity and control consequents are the percentage of chilled and hot water flow rates at summer and the percentage of hot water and steam injected flow rates at winter. A computer simulation has been conducted and fuzzy control results are compared with that of conventional Proportional-Integral-Derivative control. It was found that the proposed control strategy satisfies the space load and at the same time to achieve the comfort zone, as defined by the ASHRAE code. Meanwhile PID control fails to adjust the room temperature at part-load operations. It has been demonstrated that fuzzy controller operation is more efficient and consumes less energy than PID control.

  14. Development of Fuzzy Logic Control for Vehicle Air Conditioning System

    Directory of Open Access Journals (Sweden)

    Henry Nasution

    2008-08-01

    Full Text Available A vehicle air conditioning system is experimentally investigated. Measurements were taken during the experimental period at a time interval of one minute for a set point temperature of 22, 23 and 24oC with internal heat loads of 0, 1 and 2 kW. The cabin temperature and the speed of the compressor were varied and the performance of the system, energy consumption and energy saving ware analyzed. The main objective of the experimental work is to evaluate the energy saving obtained when the fuzzy logic control (FLC algorithm, through an inverter, continuously regulates the compressor speed. It demonstrates better control of the compressor operation in terms of energy consumption as compared to the control by using a thermostat imposing On/Off cycles on the compressor at the nominal frequency of 50 Hz. The experimental set-up consists of original components from the air conditioning system of a compact passenger vehicle. The experimental results indicate that the proposed technique can save energy and improve indoor comfort significantly for vehicle air conditioning systems compared to the conventional (On/Off control technique.

  15. 2-regularity and 2-normality conditions for systems with impulsive controls

    Directory of Open Access Journals (Sweden)

    Pavlova Natal'ya

    2007-01-01

    Full Text Available In this paper a controlled system with impulsive controls in the neighborhood of an abnormal point is investigated. The set of pairs (u,μ is considered as a class of admissible controls, where u is a measurable essentially bounded function and μ is a finite-dimensional Borel measure, such that for any Borel set B, μ(B is a subset of the given convex closed pointed cone. In this article the concepts of 2-regularity and 2-normality for the abstract mapping Ф, operating from the given Banach space into a finite-dimensional space, are introduced. The concepts of 2-regularity and 2-normality play a great role in the course of derivation of the first and the second order necessary conditions for the optimal control problem, consisting of the minimization of a certain functional on the set of the admissible processes. These concepts are also important for obtaining the sufficient conditions for the local controllability of the nonlinear systems. The convenient criterion for 2-regularity along the prescribed direction and necessary conditions for 2-normality of systems, linear in control, are introduced in this article as well.

  16. Design of automatic control system of temperature in radon chamber controlled by air-condition based on 485 BUS

    International Nuclear Information System (INIS)

    Man Zaigang; Wang Renbo; Zhang Xiongjie; Zhu Zhifu; Tang Bin

    2009-01-01

    Radon chamber can be widely used in various radon measurement instruments for calibration, testing and radon environment experiment. According to requisition, radon chamber temperature should be controllable from +10 degree C to +30 degree C, and the temperature control accuracy of the system reaches ±1 degree C. The design of automatic temperature controlled by air-condition based on 485 BUS is introduced. The software and hardware techniques of how the ATMEL89S52 micro controller controls air-condition and communicates with computer are elaborated on. (authors)

  17. Storage of low-level radioactive wastes in the ground hydrogeologic and hydrochemical factors (with an appendix on the Maxey Flats, Kentucky, radioactive waste storage site: current knowledge and data needs for a quantitative hydrogeologic evaluation)

    International Nuclear Information System (INIS)

    Papadopulos, S.S.; Winograd, I.J.

    1974-01-01

    Hydrogeologic criteria presented by Cherry and others (1973) are adopted as a guideline to define the hydrogeologic and hydrochemical data needs for the evaluation of the suitability of proposed or existing low-level radioactive waste burial sites. Evaluation of the suitability of a site requires the prediction of flow patterns and of rates of nuclide transport in the regional hydrogeologic system. Such predictions can be made through mathematical simulation of flow and solute transport in porous media. The status of mathematical simulation techniques, as they apply to radioactive waste burial sites, is briefly reviewed, and hydrogeologic and hydrochemical data needs are listed in order of increasing difficulty and cost of acquisition. Predictive modeling, monitoring, and management of radionuclides dissolved and transported by ground water can best be done for sites in relatively simple hydrogeologic settings; namely, in unfaulted relatively flat-lying strata of intermediate permeability such as silt, siltstone and silty sandstone. In contrast, dense fractured or soluble media and poorly permeable porous media (aquitards) are not suitable for use as burial sites, first, because of media heterogeneity and difficulties of sampling, and consequently of predictive modeling, and, second, because in humid zones burial trenches in aquitards may overflow. A buffer zone several thousands of feet to perhaps several miles around existing or proposed sites is a mandatory consequence of the site selection criteria. As a specific example, the Maxey Flats, Kentucky low-level waste disposal site is examined. (U.S.)

  18. Alignment Condition-Based Robust Adaptive Iterative Learning Control of Uncertain Robot System

    Directory of Open Access Journals (Sweden)

    Guofeng Tong

    2014-04-01

    Full Text Available This paper proposes an adaptive iterative learning control strategy integrated with saturation-based robust control for uncertain robot system in presence of modelling uncertainties, unknown parameter, and external disturbance under alignment condition. An important merit is that it achieves adaptive switching of gain matrix both in conventional PD-type feedforward control and robust adaptive control in the iteration domain simultaneously. The analysis of convergence of proposed control law is based on Lyapunov's direct method under alignment initial condition. Simulation results demonstrate the faster learning rate and better robust performance with proposed algorithm by comparing with other existing robust controllers. The actual experiment on three-DOF robot manipulator shows its better practical effectiveness.

  19. Groundwater flow and heterogeneous discharge into a seepage lake

    DEFF Research Database (Denmark)

    Kazmierczak, Jolanta; Müller, Sascha; Nilsson, B.

    2016-01-01

    with the lake remained under seemingly steady state conditions across seasons, a high spatial and temporal heterogeneity in the discharge to the lake was observed. The results showed that part of the groundwater flowing from the west passes beneath the lake and discharges at the eastern shore, where groundwater......Groundwater discharge into a seepage lake was investigated by combining flux measurements, hydrochemical tracers, geological information, and a telescopic modeling approach using first two-dimensional (2-D) regional then 2-D local flow and flow path models. Discharge measurements and hydrochemical...... tracers supplement each other. Discharge measurements yield flux estimates but rarely provide information about the origin and flow path of the water. Hydrochemical tracers may reveal the origin and flow path of the water but rarely provide any information about the flux. While aquifer interacting...

  20. Age-related effects on postural control under multi-task conditions.

    Science.gov (United States)

    Granacher, Urs; Bridenbaugh, Stephanie A; Muehlbauer, Thomas; Wehrle, Anja; Kressig, Reto W

    2011-01-01

    Changes in postural sway and gait patterns due to simultaneously performed cognitive (CI) and/or motor interference (MI) tasks have previously been reported and are associated with an increased risk of falling in older adults. The objectives of this study were to investigate the effects of a CI and/or MI task on static and dynamic postural control in young and elderly subjects, and to find out whether there is an association between measures of static and dynamic postural control while concurrently performing the CI and/or MI task. A total of 36 healthy young (n = 18; age: 22.3 ± 3.0 years; BMI: 21.0 ± 1.6 kg/m(2)) and elderly adults (n = 18; age: 73.5 ± 5.5 years; BMI: 24.2 ± 2.9 kg/m(2)) participated in this study. Static postural control was measured during bipedal stance, and dynamic postural control was obtained while walking on an instrumented walkway. Irrespective of the task condition, i.e. single-task or multiple tasks, elderly participants showed larger center-of-pressure displacements and greater stride-to-stride variability than younger participants. Associations between measures of static and dynamic postural control were found only under the single-task condition in the elderly. Age-related deficits in the postural control system seem to be primarily responsible for the observed results. The weak correlations detected between static and dynamic measures could indicate that fall-risk assessment should incorporate dynamic measures under multi-task conditions, and that skills like erect standing and walking are independent of each other and may have to be trained complementarily. Copyright © 2010 S. Karger AG, Basel.

  1. Constitutive mass balance relations between chemical composition, volume, density, porosity, and strain in metasomatic hydrochemical systems: Results on weathering and pedogenesis

    Science.gov (United States)

    Brimhall, George H.; Dietrich, William E.

    1987-03-01

    Relations characterizing the chemical, physical, and mechanical changes resulting from metasomatic hydrochemical processes are developed using mass balance models which formally link chemical composition to bulk density, mineral density, volumetric properties, porosity, and amount of deformation (strain). Rigorous analysis of aqueous solute transport effects is then made possible in a variety of porous media flow environments including chemical weathering, pedogenesis (soil formation), diagenesis, ore deposition and enrichment, and metamorphism. Application of these linear constitutive relations to chemical weathering profiles shows that immobile and locally mobile chemical elements, with masses conserved on the scale of soil profiles, can be accurately identified from analysis of appropriate data arrays and then used as natural geochemical tracers to infer the nature and extent of hydrochemical weathering processes and volume changes during pedogenesis. Assumptions commonly made in the past about the supposed immobility of certain elements, e.g., Ti and Zr, become unnecessary. Quantitative differentiation between the effects of residual and supergene fractionation is then easily made. These methods are applied to Ni-rich laterites developed by weathering of ultramafic rocks, showing that during ordinary residual enrichment, Ni is concentrated by as much as 4× protolith peridotite concentrations. This occurs simply by silicate mineral dissolution and removal of chemical elements other than Ni ( e.g., Mg) with a corresponding reduction in saprolite density and increase in bulk porosity without significant deformation. In contrast, laterites with mineable concentrations of Ni which are similarly undeformed (such as the Nickel Mountain Mine in Riddle, Oregon) have experienced, in addition to residual enrichment, strong supergene enrichment by fractionation of ore elements between a leached zone from which Ni is extracted and a complementary enriched zone positioned

  2. Theoretical Background for the Decision-Making Process Modelling under Controlled Intervention Conditions

    Directory of Open Access Journals (Sweden)

    Bakanauskienė Irena

    2017-12-01

    Full Text Available This article is intended to theoretically justify the decision-making process model for the cases, when active participation of investing entities in controlling the activities of an organisation and their results is noticeable. Based on scientific literature analysis, a concept of controlled conditions is formulated, and using a rational approach to the decision-making process, a model of the 11-steps decision-making process under controlled intervention is presented. Also, there have been unified conditions, describing the case of controlled interventions thus providing preconditions to ensure the adequacy of the proposed decision-making process model.

  3. Overview of impurity control and wall conditioning in NSTX

    International Nuclear Information System (INIS)

    Kugel, H.W.; Maingi, R.; Wampler, W.; Barry, R.E.; Bell, M.; Blanchard, W.; Gates, D.; Johnson, D.; Kaita, R.; Kaye, S.; Maqueda, R.; Menard, J.; Menon, M.M.; Mueller, D.; Ono, M.; Paul, S.; Peng, Y-K.M.; Raman, R.; Roquemore, A.; Skinner, C. H.; Sabbagh, S.; Stratton, B.; Stutman, D.; Wilson, J. R.; Zweben, S.

    2000-01-01

    The National Spherical Torus Experiment (NSTX) started plasma operations i n February 1999. In the first extended period of experiments, NSTX achieved high current, inner wall limited, double null, and single null plasma discharges, initial Coaxial Helicity Injection, and High Harmonic Fast Wave results. As expected, discharge reproducibility and performance were strongly affected by wall conditions. In this paper, the authors describe the internal geometry, and initial plasma discharge, impurity control, wall conditioning, erosion, and deposition results

  4. Controlling Relations in Baseline Conditional Discriminations as Determinants of Stimulus Equivalence

    Science.gov (United States)

    de Rose, Julio C.; Hidalgo, Matheus; Vasconcellos, Mariliz

    2013-01-01

    Variation in baseline controlling relations is suggested as one of the factors determining variability in stimulus equivalence outcomes. This study used single- comparison trials attempting to control such controlling relations. Four children learned AB, BC, and CD conditional discriminations, with 2 samples and 2 comparison stimuli. In Condition…

  5. Modified atmospheric conditions controlling fungal growth on cheese

    DEFF Research Database (Denmark)

    Nielsen, Per Væggemose

    1997-01-01

    Effective control of fungal growth on cheese under storage conditions is of great concern for the dairy industry. Therefore we designed a research project together with the Danish dairy industry on modelling fungal growth on cheese as affected by the combined effect of storage conditions (O2 and CO......2 level, relative humidity and temperature) and the composition of the cheese. All fungal species commonly found on cheese, starter cultures as well as contaminants, were examined.The most important factors influencing fungal growth are temperature, water activity of the medium and the carbon...... a competitive advantage over other fungi in moist conditions with high carbon dioxide levels, such as inside a roquefort cheese or in gas tight grain storage. The key to success in food packaging is to recognise the food ecosystem, as it enables us to identify which micro...

  6. A new method for controlling refrigerant flow in automobile air conditioning

    Energy Technology Data Exchange (ETDEWEB)

    Xuquan Li; Jiangping Chen; Zhijiu Chen [Shanghai Jiao Tong University (China). Institute of Refrigeration and Cryogenics Engineering; Weihua Liu; Wei Hu; Xiaobing Liu [Shanghai Delphi Automotive Air Conditiong Systems Co. Ltd., Changhai (China)

    2004-05-01

    This paper describes the improvement of the refrigerant flow control method by using an electronic expansion valve (EEV) which is driven by a stepper motor in automobile air conditioning system. An EEV can make a quick response to the abrupt change in the refrigerant flow rate during the change in automobile speed and the thermostatic on/off operation. The flow rate characteristic of the EEV for automobile air conditioning was presented. A microcontroller is used to receive the input signal and generate the output signal to control the opening of the EEV. The fuzzy self-tuning proportional-integral-derivative (PID) control method is employed. Experimental results show that the new control method can feed adequate refrigerant flow into the evaporator in various operations. The evaporator discharge air temperature has dropped by approximately 3{sup o}C as compared with that of the conventional PID control system. (author)

  7. Air Traffic Controllers' Control Strategies in the Terminal Area Under Off-Nominal Conditions

    Science.gov (United States)

    Martin, Lynne; Mercer, Joey; Callantine, Todd; Kupfer, Michael; Cabrall, Christopher

    2012-01-01

    A human-in-the-loop simulation investigated the robustness of a schedule-based terminal-area air traffic management concept, and its supporting controller tools, to off-nominal events - events that led to situations in which runway arrival schedules required adjustments and controllers could no longer use speed control alone to impose the necessary delays. The main research question was exploratory: to assess whether controllers could safely resolve and control the traffic during off-nominal events. A focus was the role of the supervisor - how he managed the schedules, how he assisted the controllers, what strategies he used, and which combinations of tools he used. Observations and questionnaire responses revealed supervisor strategies for resolving events followed a similar pattern: a standard approach specific to each type of event often resolved to a smooth conclusion. However, due to the range of factors influencing the event (e.g., environmental conditions, aircraft density on the schedule, etc.), sometimes the plan required revision and actions had a wide-ranging effect.

  8. Pointwise second-order necessary optimality conditions and second-order sensitivity relations in optimal control

    Science.gov (United States)

    Frankowska, Hélène; Hoehener, Daniel

    2017-06-01

    This paper is devoted to pointwise second-order necessary optimality conditions for the Mayer problem arising in optimal control theory. We first show that with every optimal trajectory it is possible to associate a solution p (ṡ) of the adjoint system (as in the Pontryagin maximum principle) and a matrix solution W (ṡ) of an adjoint matrix differential equation that satisfy a second-order transversality condition and a second-order maximality condition. These conditions seem to be a natural second-order extension of the maximum principle. We then prove a Jacobson like necessary optimality condition for general control systems and measurable optimal controls that may be only ;partially singular; and may take values on the boundary of control constraints. Finally we investigate the second-order sensitivity relations along optimal trajectories involving both p (ṡ) and W (ṡ).

  9. Process-based karst modelling to relate hydrodynamic and hydrochemical characteristics to system properties

    Directory of Open Access Journals (Sweden)

    A. Hartmann

    2013-08-01

    Full Text Available More than 30% of Europe's land surface is made up of karst exposures. In some countries, water from karst aquifers constitutes almost half of the drinking water supply. Hydrological simulation models can predict the large-scale impact of future environmental change on hydrological variables. However, the information needed to obtain model parameters is not available everywhere and regionalisation methods have to be applied. The responsive behaviour of hydrological systems can be quantified by individual metrics, so-called system signatures. This study explores their value for distinguishing the dominant processes and properties of five different karst systems in Europe and the Middle East. By defining ten system signatures derived from hydrodynamic and hydrochemical observations, a process-based karst model is applied to the five karst systems. In a stepwise model evaluation strategy, optimum parameters and their sensitivity are identified using automatic calibration and global variance-based sensitivity analysis. System signatures and sensitive parameters serve as proxies for dominant processes, and optimised parameters are used to determine system properties. By sensitivity analysis, the set of system signatures was able to distinguish the karst systems from one another by providing separate information about dominant soil, epikarst, and fast and slow groundwater flow processes. Comparing sensitive parameters to the system signatures revealed that annual discharge can serve as a proxy for the recharge area, that the slopes of the high flow parts of the flow duration curves correlate with the fast flow storage constant, and that the dampening of the isotopic signal of the rain as well as the medium flow parts of the flow duration curves have a non-linear relation to the distribution of groundwater storage constants that represent the variability of groundwater flow dynamics. Our approach enabled us to identify dominant processes of the

  10. A hydrochemical and isotopic case study around a near surface radioactive waste disposal

    International Nuclear Information System (INIS)

    Szanto, Zs.; Svingor, E.; Futo, I.; Palcsu, L.; Molnar, M.; Rinyu, L.

    2007-01-01

    As part of the site characterisation program for the near surface radioactive waste treatment and disposal facility (RWTDF) at Puespoekszilagy, Hungary, water quality and environmental isotope investigations have been carried out. Water samples for major ion chemistry, tritium, 14 C and stable isotope ratio measurements (δ 18 O, δD, δ 34 S, δ 13 C) were taken quarterly from the observation wells, the streams and the precipitation during the period 1999-2001. The chemical composition of groundwaters presented a continuous transition from waters situated on one side to waters on the top and on the other slope of the disposal suggesting the mixing of the three hydrochemical ''endmembers''. Most of δD and δ 18 O data were situated between GMWL and LMWL (δD = 7.2 x δ 18 O - 1 permille) with Oligocene aquifer presenting recharge of Pleistocene origin and water on the top and the gentle slope of the hill presenting recharge of Holocene origin. δ 34 S values of dissolved sulphates varied in a wide range (-14.2 permille to +5.4 permille). The tritium in precipitation varied between 4.4 and 18.1 TU with an annual weighted average of 10 ± 0.3 TU. The streams showed larger fluctuations than the wells, but the changes of δ 18 O, δD and T were small compared to those in precipitation (showing seasonal variation). Stable isotope, tritium and radiocarbon data proved that the replenishment of groundwater is slow on the steeper side and the direction of water movement is toward the gentle slope of the hill. It was judged that this path is the one that is most likely to give rise to high doses and, therefore, was used in the hydrological modelling of the safety assessment that followed the present work. The possibility that there may also be transport through the unsaturated zone and systems of perched water tables in layers 1 and 2 to both the Szilagyi and Nemedi streams cannot be excluded; the transport along these pathways is likely to be intermittent. (orig.)

  11. Existence conditions of optimal trajectories in dynamic control processes; Conditions d'existence de trajectoires optimales des processus dynamiques commandes

    Energy Technology Data Exchange (ETDEWEB)

    Bonnemay-Juricek, L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    The existence of solutions in the optimal control problems with free endpoints is studied in this report and existence conditions are established without the usual assumption that the control region is convex. Furthermore the results, in order to be of some utility in physical applications, are expressed only by means of conditions on the parameters defining the system. (author) [French] Ce rapport etudie l'existence de solutions optimales dans les problemes de commande ou le point terminal est libre et ou la duree de l'evolution du systeme a optimiser est connue. Des conditions d'existence y sont formulees sans recourir a l'hypothese usuelle de convexite du domaine des valeurs des commandes. De plus on a cherche a rendre utilisables les resultats en ne faisant porter les conditions que sur les parametres directement accessibles du systeme. (auteur)

  12. Social proof in the supermarket : Promoting healthy choices under low self-control conditions

    NARCIS (Netherlands)

    Salmon, Stefanie J.; De Vet, Emely; Adriaanse, Marieke A.; Fennis, Bob M.; Veltkamp, Martijn; De Ridder, Denise T. D.

    2015-01-01

    Under low self-control conditions, people often favor tempting but unhealthy food products. Instead of fighting against low self-control to reduce unhealthy food choices, we aim to demonstrate in a field study that heuristic decision tendencies can be exploited under these conditions. To do so a

  13. Social proof in the supermarket: Promoting healthy choices under low self-control conditions

    NARCIS (Netherlands)

    Salmon, S.J.; Vet, de E.; Adriaanse, M.A.; Fennis, B.M.; Veltkamp, M.; Ridder, de D.T.D.

    2015-01-01

    Under low self-control conditions, people often favor tempting but unhealthy food products. Instead of fighting against low self-control to reduce unhealthy food choices, we aim to demonstrate in a field study that heuristic decision tendencies can be exploited under these conditions. To do so a

  14. Shifts in stream hydrochemistry in responses to typhoon and non-typhoon precipitation

    Science.gov (United States)

    Chang, Chung-Te; Huang, -Chuan, Jr.; Wang, Lixin; Shih, Yu-Ting; Lin, Teng-Chiu

    2018-04-01

    Climate change is projected to increase the intensity and frequency of extreme climatic events such as tropical cyclones. However, few studies have examined the responses of hydrochemical processes to climate extremes. To fill this knowledge gap, we compared the relationship between stream discharge and ion input-output budget during typhoon and non-typhoon periods in four subtropical mountain watersheds with different levels of agricultural land cover in northern Taiwan. The results indicated that the high predictability of ion input-output budgets using stream discharge during the non-typhoon period largely disappeared during the typhoon periods. For ions such as Na+, NH4+, and PO43-, the typhoon period and non-typhoon period exhibited opposite discharge-budget relationships. In other cases, the discharge-budget relationship was driven by the typhoon period, which consisted of only 7 % of the total time period. The striking differences in the discharge-ion budget relationship between the two periods likely resulted from differences in the relative contributions of surface runoff, subsurface runoff and groundwater, which had different chemical compositions, to stream discharge between the two periods. Watersheds with a 17-22 % tea plantation cover showed large increases in NO3- export with increases in stream discharge. In contrast, watersheds with 93-99 % forest cover showed very mild or no increases in NO3- export with increases in discharge and very low levels of NO3- export even during typhoon storms. The results suggest that even mild disruption of the natural vegetation could largely alter hydrochemical processes. Our study clearly illustrates significant shifts in hydrochemical responses between regular and typhoon precipitation. We propose that hydrological models should separate hydrochemical processes into regular and extreme conditions to better capture the whole spectrum of hydrochemical responses to a variety of climate conditions.

  15. Shifts in stream hydrochemistry in responses to typhoon and non-typhoon precipitation

    Directory of Open Access Journals (Sweden)

    C.-T. Chang

    2018-04-01

    Full Text Available Climate change is projected to increase the intensity and frequency of extreme climatic events such as tropical cyclones. However, few studies have examined the responses of hydrochemical processes to climate extremes. To fill this knowledge gap, we compared the relationship between stream discharge and ion input–output budget during typhoon and non-typhoon periods in four subtropical mountain watersheds with different levels of agricultural land cover in northern Taiwan. The results indicated that the high predictability of ion input–output budgets using stream discharge during the non-typhoon period largely disappeared during the typhoon periods. For ions such as Na+, NH4+, and PO43−, the typhoon period and non-typhoon period exhibited opposite discharge–budget relationships. In other cases, the discharge–budget relationship was driven by the typhoon period, which consisted of only 7 % of the total time period. The striking differences in the discharge–ion budget relationship between the two periods likely resulted from differences in the relative contributions of surface runoff, subsurface runoff and groundwater, which had different chemical compositions, to stream discharge between the two periods. Watersheds with a 17–22 % tea plantation cover showed large increases in NO3− export with increases in stream discharge. In contrast, watersheds with 93–99 % forest cover showed very mild or no increases in NO3− export with increases in discharge and very low levels of NO3− export even during typhoon storms. The results suggest that even mild disruption of the natural vegetation could largely alter hydrochemical processes. Our study clearly illustrates significant shifts in hydrochemical responses between regular and typhoon precipitation. We propose that hydrological models should separate hydrochemical processes into regular and extreme conditions to better capture the whole spectrum of hydrochemical responses to a

  16. Controlled damping of a physical pendulum: experiments near critical conditions

    International Nuclear Information System (INIS)

    Gonzalez, Manuel I; Bol, Alfredo

    2006-01-01

    This paper presents an experimental device for the study of damped oscillatory motion along with three associated experiments. Special emphasis is given on both didactic aspects and the interactivity of the experimental set-up, in order to assist students in understanding fundamental aspects of damped oscillatory motion and allow them to directly compare their experimental results with the well-known theory they can find in textbooks. With this in mind, a physical pendulum was selected with an eddy-current damping system that allows the damping conditions to be controlled with great precision. The three experiments examine accurate control of damping, frequency shift near critical damping and the transition from underdamped to overdamped conditions

  17. Transducer placement for robustness to variations in boundary conditions for active structural acoustic control

    Science.gov (United States)

    Sprofera, Joseph D.; Clark, Robert L.; Cabell, Randolph H.; Gibbs, Gary P.

    2005-05-01

    Turbulent boundary layer (TBL) noise is considered a primary contribution to the interior noise present in commercial airliners. There are numerous investigations of interior noise control devoted to aircraft panels; however, practical realization is a potential challenge since physical boundary conditions are uncertain at best. In most prior studies, pinned or clamped boundary conditions were assumed; however, realistic panels likely display a range of boundary conditions between these two limits. Uncertainty in boundary conditions is a challenge for control system designers, both in terms of the compensator implemented and the location of transducers required to achieve the desired control. The impact of model uncertainties, specifically uncertain boundaries, on the selection of transducer locations for structural acoustic control is considered herein. The final goal of this work is the design of an aircraft panel structure that can reduce TBL noise transmission through the use of a completely adaptive, single-input, single-output control system. The feasibility of this goal is demonstrated through the creation of a detailed analytical solution, followed by the implementation of a test model in a transmission loss apparatus. Successfully realizing a control system robust to variations in boundary conditions can lead to the design and implementation of practical adaptive structures that could be used to control the transmission of sound to the interior of aircraft. Results from this research effort indicate it is possible to optimize the design of actuator and sensor location and aperture, minimizing the impact of boundary conditions on the desired structural acoustic control.

  18. Control Strategy for Microgrid Inverter under Unbalanced Grid Voltage Conditions

    DEFF Research Database (Denmark)

    Guo, Xiaoqiang; Liu, Wenzhao; Zhang, X.

    2014-01-01

    This paper presents the theoretical analysis of the inherent reason of current harmonic and power oscillation phenomena in case of operating the microgrid inverter under unbalanced grid voltage conditions. In order to flexibly control the current harmonic and power oscillation, a new stationary...... inverter. Finally, the performance evaluation tests are carried out under unbalanced grid voltage conditions. Results verify the effectiveness of the propose method....

  19. Monitoring parameters of technical condition and safety of aircraft using control charts

    Directory of Open Access Journals (Sweden)

    В.І. Чепіженко

    2007-03-01

    Full Text Available  The opportunity of control cards use for monitoring of a technical condition parameters and reliability of aviation techniques is considered at its operation on a technical condition.

  20. Smart Sensors Enable Smart Air Conditioning Control

    Directory of Open Access Journals (Sweden)

    Chin-Chi Cheng

    2014-06-01

    Full Text Available In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants’ information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans’ intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It’s also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection.

  1. Distributed automatic control of technological processes in conditions of weightlessness

    Science.gov (United States)

    Kukhtenko, A. I.; Merkulov, V. I.; Samoylenko, Y. I.; Ladikov-Royev, Y. P.

    1986-01-01

    Some problems associated with the automatic control of liquid metal and plasma systems under conditions of weightlessness are examined, with particular reference to the problem of stability of liquid equilibrium configurations. The theoretical fundamentals of automatic control of processes in electrically conducting continuous media are outlined, and means of using electromagnetic fields for simulating technological processes in a space environment are discussed.

  2. Reactive gas control of non-stable plasma conditions

    International Nuclear Information System (INIS)

    Bellido-Gonzalez, V.; Daniel, B.; Counsell, J.; Monaghan, D.

    2006-01-01

    Most industrial plasma processes are dependant upon the control of plasma properties for repeatable and reliable production. The speed of production and range of properties achieved depend on the degree of control. Process control involves all the aspects of the vacuum equipment, substrate preparation, plasma source condition, power supplies, process drift, valves (inputs/outputs), signal and data processing and the user's understanding and ability. In many cases, some of the processes which involve the manufacturing of interesting coating structures, require a precise control of the process in a reactive environment [S.J. Nadel, P. Greene, 'High rate sputtering technology for throughput and quality', International Glass Review, Issue 3, 2001, p. 45. ]. Commonly in these circumstances the plasma is not stable if all the inputs and outputs of the system were to remain constant. The ideal situation is to move a process from set-point A to B in zero time and maintain the monitored signal with a fluctuation equal to zero. In a 'real' process that's not possible but improvements in the time response and energy delivery could be achieved with an appropriate algorithm structure. In this paper an advanced multichannel reactive plasma gas control system is presented. The new controller offers both high-speed gas control combined with a very flexible control structure. The controller uses plasma emission monitoring, target voltage or any process sensor monitoring as the input into a high-speed control algorithm for gas input. The control algorithm and parameters can be tuned to different process requirements in order to optimize response times

  3. Adaptive neural network motion control for aircraft under uncertainty conditions

    Science.gov (United States)

    Efremov, A. V.; Tiaglik, M. S.; Tiumentsev, Yu V.

    2018-02-01

    We need to provide motion control of modern and advanced aircraft under diverse uncertainty conditions. This problem can be solved by using adaptive control laws. We carry out an analysis of the capabilities of these laws for such adaptive systems as MRAC (Model Reference Adaptive Control) and MPC (Model Predictive Control). In the case of a nonlinear control object, the most efficient solution to the adaptive control problem is the use of neural network technologies. These technologies are suitable for the development of both a control object model and a control law for the object. The approximate nature of the ANN model was taken into account by introducing additional compensating feedback into the control system. The capabilities of adaptive control laws under uncertainty in the source data are considered. We also conduct simulations to assess the contribution of adaptivity to the behavior of the system.

  4. M3 version 3.0: Verification and validation; Hydrochemical model of ground water at repository site

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Javier B. (Dept. of Earth Sciences, Univ. of Zaragoza, Zaragoza (Spain)); Laaksoharju, Marcus (Geopoint AB, Sollentuna (Sweden)); Skaarman, Erik (Abscondo, Bromma (Sweden)); Gurban, Ioana (3D-Terra (Canada))

    2009-01-15

    Hydrochemical evaluation is a complex type of work that is carried out by specialists. The outcome of this work is generally presented as qualitative models and process descriptions of a site. To support and help to quantify the processes in an objective way, a multivariate mathematical tool entitled M3 (Multivariate Mixing and Mass balance calculations) has been constructed. The computer code can be used to trace the origin of the groundwater, and to calculate the mixing proportions and mass balances from groundwater data. The M3 code is a groundwater response model, which means that changes in the groundwater chemistry in terms of sources and sinks are traced in relation to an ideal mixing model. The complexity of the measured groundwater data determines the configuration of the ideal mixing model. Deviations from the ideal mixing model are interpreted as being due to reactions. Assumptions concerning important mineral phases altering the groundwater or uncertainties associated with thermodynamic constants do not affect the modelling because the calculations are solely based on the measured groundwater composition. M3 uses the opposite approach to that of many standard hydrochemical models. In M3, mixing is evaluated and calculated first. The constituents that cannot be described by mixing are described by reactions. The M3 model consists of three steps: the first is a standard principal component analysis, followed by mixing and finally mass balance calculations. The measured groundwater composition can be described in terms of mixing proportions (%), while the sinks and sources of an element associated with reactions are reported in mg/L. This report contains a set of verification and validation exercises with the intention of building confidence in the use of the M3 methodology. At the same time, clear answers are given to questions related to the accuracy and the precision of the results, including the inherent uncertainties and the errors that can be made

  5. Hydrochemical and isotopic studies in two neighboring river basins in semiarid regions of Minas Gerais

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Vinícius G.; Moreira, Rubens M.; Carvalho, Carlos A., E-mail: vinicius.ferreira@cdtn.br, E-mail: rubens@cdtn.br, E-mail: cacf@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Serviço de Meio Ambiente

    2017-07-01

    Groundwater is the largest reservoir of fresh water on Earth and the depletion of aquifer systems is a reality, both in semi-arid and humid regions. The hydrology of watersheds is a field of study that is concerned with the movement of waters from the rains and its physical-chemical changes. Groundwater resources in these regions are a sensitive issue, requiring careful management to avoid quality degradation. The present study focuses the groundwater system at the interface of the Pandeiros and Peruaçu river basins in the northwest region of Minas Gerais State. The methods used were the evaluations of the hydrochemistry, as well as isotopic, and physicochemical parameters, allied to geological studies to investigate surface and groundwater, their possible interactions and spatial distribution. The hydrochemical results correlated with the physicochemical measurements show water contrasts in the study area, which is geologically composed from bottom to top by gneisses and granites (Januaria Complex), limestone and siltstones (Bambuí Group), sandstones and eluvial sediments (Urucuia Group), eluvio-coluvial cover and alluvial deposits. It has been observed that waters in the context of sandstones and siliceous sediments are sodium bicarbonate waters, slightly acidic pH and low in TDS, whereas waters in pedological / geologic context of limestones are calcium bicarbonate waters exhibiting basic pH and high TDS. The deuterium (D) and oxygen-18 signatures of the groundwater are compared to the global meteoric water line (GMWL). The average values of the isotopes in the study area are slightly variable, indicating that the isotopic signatures are related to rainfall precipitation. It has been possible to suggest an evaporation line pattern starting from the position of springs, passing though streams and finally ending in the lagoon. The local evaporation line can be represented by the equation δD = 5,8 δ{sup 18}O - 2,4. (author)

  6. An Innovative Adaptive Control System to Regulate Microclimatic Conditions in a Greenhouse

    Directory of Open Access Journals (Sweden)

    Giuseppina Nicolosi

    2017-05-01

    Full Text Available In the recent past home automation has been expanding its objectives towards new solutions both inside the smart home and in its outdoor spaces, where several new technologies are available. This work has developed an approach to integrate intelligent microclimatic greenhouse control into integrated home automation. Microclimatic control of greenhouses is a critical issue in agricultural practices, due to often common sudden daily variation of climatic conditions, and to its potentially detrimental effect on plant growth. A greenhouse is a complex thermodynamic system where indoor temperature and relative humidity have to be closely monitored to facilitate plant growth and production. This work shows an adaptive control system tailored to regulate microclimatic conditions in a greenhouse, by using an innovative combination of soft computing applications. In particular, a neural network solution has been proposed in order to forecast the climatic behavior of greenhouse, while a parallel fuzzy scheme approach is carried out in order to adjust the air speed of fan-coil and its temperature. The proposed combined approach provides a better control of greenhouse climatic conditions due to the system’s capability to base instantaneous solutions both on real measured variables and on forecasted climatic change. Several simulation campaigns were carried out to perform accurate neural network and fuzzy schemes, aimed at obtaining respectively a minimum forecasted error value and a more appropriate fuzzification and de-fuzzification process. A Matlab/Simulink solution implemented with a combined approach and its relevant obtained performance is also shown in present study, demonstrating that through controlled parameters it will be possible to maintain a better level of indoor climatic conditions. In the present work we prove how with a forecast of outside temperature at the next time-instant and rule-based controller monitoring of cooling or heating air

  7. Microcontroller Based Proportional Derivative Plus Conditional Integral Controller for Electro-Mechanical Dual Acting Pulley Continuously Variable Transmission Ratio Control

    International Nuclear Information System (INIS)

    Budianto, A; Tawi, K B; Hussein, M; Supriyo, B; Kob, M S Che; Zulkifli, Mohd Ezlamy; Khairuldean A K; Daraoh, Aishah; Ariyono, S

    2012-01-01

    Electro-Mechanical Dual Acting Pulley (EMDAP) Continuously Variable Transmission (CVT) is a transmission utilized by electro-mechanical actuated system. It has a potential to reduce energy consumption because it only needs power during changing CVT ratio and no power is needed to maintain CVT ratio due to self lock mechanism design. This paper proposed simple proportional derivative plus conditional integral (PDCI) controller to control EMDAP CVT ratio which can be simply implemented on a microcontroller. This proposed controller used Astrom-Hagglund method and Ziegler-Nichols formula to tune PDCI gain. The Proportional Derivative controller is directly activated from the start but Integral controller is only activated when the error value reaches error value setting point. Simulation using Matlab/Simulink software was conducted to evaluate PDCI system performance. The simulation results showed PDCI controller has ability to perform maximum overshoot 0.1%, 0.001 steady state error and 0.5s settling time. For clamping condition, settling time is about 11.46s during changing ratio from 2.0 to 0.7, while for release condition, settling time is about 8.33s during changing ratio from 0.7 to 2.0.

  8. Existence conditions of optimal trajectories in dynamic control processes; Conditions d'existence de trajectoires optimales des processus dynamiques commandes

    Energy Technology Data Exchange (ETDEWEB)

    Bonnemay-Juricek, L. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    The existence of solutions in the optimal control problems with free endpoints is studied in this report and existence conditions are established without the usual assumption that the control region is convex. Furthermore the results, in order to be of some utility in physical applications, are expressed only by means of conditions on the parameters defining the system. (author) [French] Ce rapport etudie l'existence de solutions optimales dans les problemes de commande ou le point terminal est libre et ou la duree de l'evolution du systeme a optimiser est connue. Des conditions d'existence y sont formulees sans recourir a l'hypothese usuelle de convexite du domaine des valeurs des commandes. De plus on a cherche a rendre utilisables les resultats en ne faisant porter les conditions que sur les parametres directement accessibles du systeme. (auteur)

  9. Developed adaptive neuro-fuzzy algorithm to control air conditioning ...

    African Journals Online (AJOL)

    user

    ... conditioning system is highly appreciated and essential in most of our daily life. ... (Hossien and Karla, 2012) presented an overview work which provides an .... energy balance for SSSF and the mass flow balance for the water in the air are ..... of Automatic Control and Electrical Engineering at Siegen University, Germany.

  10. Potential electricity savings by variable speed control of compressor for air conditioning systems

    Energy Technology Data Exchange (ETDEWEB)

    Nasution, Henry [Bung Hatta University, Department of Mechanical Engineering, Faculty of Industrial Engineering, Padang, West Sumatera (Indonesia); Wan Hassan, Mat Nawi [Universiti Teknologi Malaysia, Faculty of Mechanical Engineering, Skudai, Johor Bahru-Darul Ta' zim (Malaysia)

    2006-05-15

    The potential of a variable-speed compressor running on a controller to provide enhanced load-matching capability, energy saving and thermal comfort for application in air-conditioning system is demonstrated. An air-conditioning system, originally operated on a constant speed mode, is retrofitted with an inverter and a PID controller. The system was installed to a thermal environmental room together with a data acquisition system to monitor energy consumption and temperature of the room. Measurements were taken 2 h daily at a time interval of 5 min for an on/off and an inverter variable-speed conditions. The results indicate that thermal comfort of the room together with energy saving can be obtained through a proper selection of K for the controller. At a temperature setting of 22 C, the energy saving for the system is estimated to reach 25.3% for PID controllers. (orig.)

  11. Optimal control of distributed parameter system with incomplete information about the initial condition

    International Nuclear Information System (INIS)

    Kotarski, W.; Kowalewski, A.

    1982-03-01

    In this paper we consider an optimal control problem for a system described by a linear partial differential equation of the parabolic type with Dirichlet's boundary condition. We impose some constraints on the control. The performance functional has the integral form. The control time T is fixed. The initial condition is not given by a known function but belongs to a certain set (incomplete information about the initial state). The problem formulated in this paper describes the process of optimal heating, of which we do not have exact information about the initial temperature on the heated object. We present an example in which the set of admissible controls and one of initial conditions are given by means of the norm constraints too. The application of the well-known projective gradient method in the Hilbert space allows us to obtain the numerical solution for our optimization problem. (author)

  12. Operating wind turbines in strong wind conditions by using feedforward-feedback control

    International Nuclear Information System (INIS)

    Feng, Ju; Sheng, Wen Zhong

    2014-01-01

    Due to the increasing penetration of wind energy into power systems, it becomes critical to reduce the impact of wind energy on the stability and reliability of the overall power system. In precedent works, Shen and his co-workers developed a re-designed operation schema to run wind turbines in strong wind conditions based on optimization method and standard PI feedback control, which can prevent the typical shutdowns of wind turbines when reaching the cut-out wind speed. In this paper, a new control strategy combing the standard PI feedback control with feedforward controls using the optimization results is investigated for the operation of variable-speed pitch-regulated wind turbines in strong wind conditions. It is shown that the developed control strategy is capable of smoothening the power output of wind turbine and avoiding its sudden showdown at high wind speeds without worsening the loads on rotor and blades

  13. Fuzzy logic controller implementation for a solar air-conditioning system

    International Nuclear Information System (INIS)

    Lygouras, J.N.; Botsaris, P.N.; Vourvoulakis, J.; Kodogiannis, V.

    2007-01-01

    The implementation of a variable structure fuzzy logic controller for a solar powered air conditioning system and its advantages are investigated in this paper. Two DC motors are used to drive the generator pump and the feed pump of the solar air-conditioner. Two different control schemes for the DC motors rotational speed adjustment are implemented and tested: the first one is a pure fuzzy controller, its output being the control signal for the DC motor driver. A 7 x 7 fuzzy matrix assigns the controller output with respect to the error value and the derivative of the error. The second scheme is a two-level controller. The lower level is a conventional PID controller, and the higher level is a fuzzy controller acting over the parameters of the low level controller. Step response of the two control loops are presented as experimental results. The contribution of this design is that in the control system, the fuzzy logic is implemented through software in a common, inexpensive, 16-bit microcontroller, which does not have special abilities for fuzzy control

  14. Fuzzy logic controller implementation for a solar air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Lygouras, J.N.; Vourvoulakis, J. [Laboratory of Electronics, School of Electrical and Computer Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100 Xanthi (Greece); Botsaris, P.N. [Laboratory of Materials, Processes and Mechanical Design, School of Production and Management Engineering, Democritus University of Thrace 67100 Xanthi (Greece); Kodogiannis, V. [Centre for Systems Analysis, School of Computer Science, University of Westminster, London, HA1 3TP (United Kingdom)

    2007-12-15

    The implementation of a variable structure fuzzy logic controller for a solar powered air conditioning system and its advantages are investigated in this paper. Two DC motors are used to drive the generator pump and the feed pump of the solar air-conditioner. Two different control schemes for the DC motors rotational speed adjustment are implemented and tested: the first one is a pure fuzzy controller, its output being the control signal for the DC motor driver. A 7 x 7 fuzzy matrix assigns the controller output with respect to the error value and the derivative of the error. The second scheme is a two-level controller. The lower level is a conventional PID controller, and the higher level is a fuzzy controller acting over the parameters of the low level controller. Step response of the two control loops are presented as experimental results. The contribution of this design is that in the control system, the fuzzy logic is implemented through software in a common, inexpensive, 16-bit microcontroller, which does not have special abilities for fuzzy control. (author)

  15. Hydrochemical and isotopic study of groundwater impacted by the acid drainage of UrÂnio Mine - Osamu Utsumi, PoÇos de Caldas Plateau (MG), Brazil; Estudo hidroqímico e isotópico das águas subterrâneas impactadas pela drenagem ácida da Mina de Urânio - OSAMU UTSUMI, planalto de Poço de Caldas, MG

    Energy Technology Data Exchange (ETDEWEB)

    Alberti, Heber Luiz Caponi

    2017-07-01

    The Osamu Utsumi Mine - MOU, belonging to the Brazilian Nuclear Industries - INB, began in 1977 with pickling activities and remained in operation until 1995. During this period, 94 million tons of rocks were removed, which caused the generation of large wasted rock piles. The intense drainage and precipitation in the study region favored the oxidation and leaching of the wasted rock piles, causing the Acid Drainage of Mine - DAM and generating effluents with low pH and high concentrations of fluoride, aluminum, iron, manganese, sulfate, zinc, uranium and Radio, among others. Currently the MOU is in the process of decommissioning and environmental remediation. The understanding of the hydrogeochemical processes and the behavior of the water flow through different aquifers is extremely important so that the actions of environmental remediation and control of the DAM are really effective. In this sense, in this work, geoprocessing and hydrochemical techniques were used to propose a conceptual hydrogeochemical model in the MOU cavity system and wasted rock pile number 4 - BF4. The geoprocessing techniques allowed to characterize and size the area under study and to integrate information on geology and mineralogy with the hydrochemical data. The hydrochemical studies were based on three groundwater sampling campaigns, using the low flow method in 17 monitoring wells, as well as 3 water reservoirs in the study area. In the collected samples were determined: (1) the main cations and anions for groundwater classification using Piper and Stiff diagrams and multivariate statistical methods (cluster and Principal Component Analysis); (2) the major long half radionuclides and {sup 222}Rn to assess radioactivity and imbalance between them; (3) the stable isotopes of {sup 18}O and {sup 2}H to provide information on the underground flows and water source; (4) the Tritium values found in the samples to estimate the age of the groundwater; (V) the sulfur and oxygen isotopes

  16. Assessment of pre-industrial carbon dioxide content in the atmosphere using hydro-chemical data

    International Nuclear Information System (INIS)

    Heans, K.A.; Liaxin, Y.I.

    2001-01-01

    A hydrochemical method has been developed to calculate concentrations of carbon dioxide (CO 2 ) in the pre-industrial atmosphere and its relationship to climatic change. The following factors affect the Earth's climate: (1) the sun with all its processes, (2) the attraction of the moon that limits the axis of inclination of the Earth, and (3) the cycle of carbon dioxide and the greenhouse effect. An imbalance in the climate system would be a major global disaster that could be detrimental for life on Earth. Recent studies and temperature measurements have shown a trend in which air temperature has increased in the troposphere in the last 100 years, affecting the normal development of natural processes. Various phenomena result from climatic change, or the gradual heating of the Earth. These include the weakening of the glacial layer that covers the Earth's surface, cycles of prolonged slowing in freeze and thaw periods of aquatic surfaces, and increased air temperature in the troposphere which can also causes abnormal fluctuations of temperature in the atmosphere, resulting in heat waves and droughts. Gradual heating of the Earth can also result in rainy periods that produce devastating floods, hurricanes and extreme winds. Changes in water temperature can influence pH levels which affect certain marine species. An increase of 5 degrees C in the global average atmospheric temperature has created changes in 420 physical processes as well as in the behavior of plants and animals. The author stated that the most drastic factor that affects the balance of the Earth's climate is the actions of man interfering with the carbon cycle, as carbon dioxide plays a vital role in the formation of the greenhouse effect. The problem results from an imbalance of the carbon dioxide cycle when CO 2 emissions are increased through the combustion of fossil fuels. It was determined that before the beginning of the Industrial Revolution, carbon dioxide in the atmosphere was 256 ppm

  17. Control of hybrid AC/DC microgrid under islanding operational conditions

    DEFF Research Database (Denmark)

    Ding, G.; Gao, F.; Zhang, S.

    2014-01-01

    This paper presents control methods for hybrid AC/DC microgrid under islanding operation condition. The control schemes for AC sub-microgrid and DC sub-microgrid are investigated according to the power sharing requirement and operational reliability. In addition, the key control schemes...... of interlinking converter with DC-link capacitor or energy storage, which will devote to the proper power sharing between AC and DC sub-microgrids to maintain AC and DC side voltage stable, is reviewed. Combining the specific control methods developed for AC and DC sub-microgrids with interlinking converter......, the whole hybrid AC/DC microgrid can manage the power flow transferred between sub-microgrids for improving on the operational quality and efficiency....

  18. Catchment hydrochemical processes controlling acidity and nitrogen in forest stream water

    International Nuclear Information System (INIS)

    Foelster, Jens

    2001-01-01

    Atmospheric deposition of air pollutants has been a severe threat to terrestrial and forest ecosystems for several decades. In Sweden sulphur deposition has caused acidification of soils and runoff, while nitrogen deposition only had a minor or local impact on runoff quality so far. During the last three decades, emission control has caused a decline in sulphur deposition, whereas nitrogen deposition on the other hand, has continued to increase to a rate several times above the natural background level. Long term changes in runoff acidity and nitrogen chemistry after these changes in deposition are of great concern. Monitoring of small, well-defined catchments including hydrochemistry of precipitation, soil and runoff, is a valuable tool for addressing this concern. When interpreting runoff data from such sites, the near-stream zone has been identified to be of crucial importance. The main objective for this thesis was to explain how catchment processes were related to short-term variation and long-term trends in the hydrochemistry of forest stream water. The field work was conducted on the strongly acidified and nitrogen limited Kindla catchment, with a special emphasis on the relationship between the near-stream zone and both stream acidity and nitrogen leaching. Furthermore, time series of hydrochemistry in forest stream water from 13 catchments were analysed for changes in acidity and nitrogen leaching. In three of these sites, soil water from E- and B-horizons was also analysed with regards to these questions. The investigations revealed that the near-stream zone was a net source of acidity in runoff at Kindla due to leaching of organic acids, although this contribution was overshadowed by sulphate from upland soils and deposition. The near-stream zone was also the main source for both organic nitrogen and nitrate to the stream, but the leaching rate was low, especially for inorganic nitrogen. In the 13 reference streams, sulphate concentrations declined in

  19. Biogeochemical Reactive Transport Model of the Redox Zone Experiment of the sp Hard Rock Laboratory in Sweden

    International Nuclear Information System (INIS)

    Molinero-Huguet, Jorge; Samper-Calvete, F. Javier; Zhang, Guoxiang; Yang, Changbing

    2004-01-01

    Underground facilities are being operated by several countries around the world for performing research and demonstration of the safety of deep radioactive waste repositories. The ''sp'' Hard Rock Laboratory is one such facility launched and operated by the Swedish Nuclear Fuel and Waste Management Company where various in situ experiments have been performed in fractured granites. One such experiment is the redox zone experiment, which aimed at evaluating the effects of the construction of an access tunnel on the hydrochemical conditions of a fracture zone. Dilution of the initially saline groundwater by fresh recharge water is the dominant process controlling the hydrochemical evolution of most chemical species, except for bicarbonate and sulfate, which unexpectedly increase with time. We present a numerical model of water flow, reactive transport, and microbial processes for the redox zone experiment. This model provides a plausible quantitatively based explanation for the unexpected evolution of bicarbonate and sulfate, reproduces the breakthrough curves of other reactive species, and is consistent with previous hydrogeological and solute transport models

  20. Energy performance and optimal control of air-conditioned buildings with envelopes enhanced by phase change materials

    International Nuclear Information System (INIS)

    Zhu Na; Wang Shengwei; Ma Zhenjun; Sun Yongjun

    2011-01-01

    Highlights: → Impact of PCM on the energy consumption and peak load demand as well as electricity cost of air-conditioned buildings. → Impact of load shifting control on energy consumption, peak load and electricity cost of air-conditioned PCM buildings. → Impact of demand limiting control on energy consumption, peak load and electricity cost of air-conditioned PCM buildings. → Energy/cost effects of different control strategies and use of PCM in energy-plus-demand-based pricing policy. → Energy/cost effects of different control strategies and use of PCM in time-based pricing policy. - Abstract: Studies are conducted to investigate the impacts of shape-stabilized phase change material (SSPCM) and different control strategies on the energy consumption and peak load demand as well as electricity cost of building air-conditioning systems at typical summer conditions in two climates (subtropical and dry continental climates). An office building using a typical variable air volume (VAV) air-conditioning system was selected and simulated as the reference building in this study. Its envelopes were enhanced by integrating the SSPCM layers into its walls while the air-conditioning system and other configurations of the building remained unchanged. The building system was tested under two typical weather conditions and two typical electricity pricing policies (i.e. time-based pricing and energy-plus-demand-based pricing). Test results show that the use of SSPCM in the building could reduce the building electricity cost significantly (over 11% in electricity cost reduction and over 20% in peak load reduction), under two pricing policies by using load shifting control and demand limiting control respectively. This paper presents the test results and the evaluation on the energy performance and the optimal control strategies of air-conditioned commercial buildings with envelopes enhanced by SSPCM.

  1. Mode switching control of dual-evaporator air-conditioning systems

    International Nuclear Information System (INIS)

    Lin, J.-L.; Yeh, T.-J.

    2009-01-01

    Modern air-conditioners incorporate variable-speed compressors and variable-opening expansion valves as the actuators for improving cooling performance and energy efficiency. These actuators have to be properly feedback-controlled; otherwise the systems may exhibit even poorer performance than the conventional machines which use fixed-speed compressors and mechanical expansion valves. Particularly for an air-conditioner with multiple evaporators, there are occasions that the machine is operated in a mode that only selected evaporator(s) is(are) turned on, and switching(s) between modes occurs(occur) during the control process. In this case, one needs to have more carefully designed control and switching strategies to ensure the system performance. In this paper, a framework for mode switching control of the dual-evaporator air-conditioning (DEAC) system is proposed. The framework is basically an integration of a controller and a dynamic compensator. The controller, which possesses the flow-distribution capability and assumes both evaporators are on throughout the control process, is intended to provide nominal performance. While mode switching is achieved by varying the reference settings in the controller, the dynamic compensator is used to improve the transient responses immediately after the switching. Experiments indicate that the proposed framework can achieve satisfactory indoor temperature regulation and provide bumpless switching between different modes of operation.

  2. Reliable Grid Condition Detection and Control of Single-Phase Distributed Power Generation Systems

    DEFF Research Database (Denmark)

    Ciobotaru, Mihai

    standards addressed to the grid-connected systems will harmonize the combination of the DPGS and the classical power plants. Consequently, the major tasks of this thesis were to develop new grid condition detection techniques and intelligent control in order to allow the DPGS not only to deliver power...... to the utility grid but also to sustain it. This thesis was divided into two main parts, namely "Grid Condition Detection" and "Control of Single-Phase DPGS". In the first part, the main focus was on reliable Phase Locked Loop (PLL) techniques for monitoring the grid voltage and on grid impedance estimation...... techniques. Additionally, a new technique for detecting the islanding mode has been developed and successfully tested. In the second part, the main reported research was concentrated around adaptive current controllers based on the information provided by the grid condition detection techniques. To guarantee...

  3. Groundwater flow modelling of periods with periglacial and glacial climate conditions - Forsmark

    International Nuclear Information System (INIS)

    Vidstrand, Patrik; Follin, Sven; Zugec, Nada

    2010-12-01

    As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The groundwater flow modelling study reported here comprises a coupled thermal-hydraulic-chemical (T-H-C) analysis of periods with periglacial and glacial climate conditions. Hydraulic-mechanical (H-M) issues are also handled but no coupled flow modelling is done. The objective of the report is to provide bounding hydrogeological estimates at different stages during glaciation and deglaciation of a glacial cycle for subsequent use in safety assessment applications within SKB's project SR-Site. Three cases with different climate conditions are analysed here: (i) Temperate case, (ii) Glacial case without permafrost, and (iii) Glacial case with permafrost. The glacial periods are transient and encompass approximately 19,000 years. The simulation results comprise residual fluid pressures, Darcy fluxes, and water salinities, as well as advective transport performance measures obtained by particle tracking such as flow path lengths, travel times and flow-related transport resistances. The modelling is accompanied by a sensitivity study that addresses the impact of the following matters: the direction of the ice sheet advance, the speed of the ice sheet margin, the bedrock hydraulic and transport properties, the temperature at the ice-subsurface interface close to the ice sheet margin, and the initial hydrochemical conditions

  4. Groundwater flow modelling of periods with periglacial and glacial climate conditions - Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Vidstrand, Patrik (TerraSolve AB, Floda (Sweden)); Follin, Sven (SF GeoLogic AB, Taeby (Sweden)); Zugec, Nada (Bergab, Stockholm (Sweden))

    2010-12-15

    As a part of the license application for a final repository for spent nuclear fuel at Forsmark, the Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken a series of groundwater flow modelling studies. These represent time periods with different hydraulic conditions and the simulations carried out contribute to the overall evaluation of the repository design and long-term radiological safety. The groundwater flow modelling study reported here comprises a coupled thermal-hydraulic-chemical (T-H-C) analysis of periods with periglacial and glacial climate conditions. Hydraulic-mechanical (H-M) issues are also handled but no coupled flow modelling is done. The objective of the report is to provide bounding hydrogeological estimates at different stages during glaciation and deglaciation of a glacial cycle for subsequent use in safety assessment applications within SKB's project SR-Site. Three cases with different climate conditions are analysed here: (i) Temperate case, (ii) Glacial case without permafrost, and (iii) Glacial case with permafrost. The glacial periods are transient and encompass approximately 19,000 years. The simulation results comprise residual fluid pressures, Darcy fluxes, and water salinities, as well as advective transport performance measures obtained by particle tracking such as flow path lengths, travel times and flow-related transport resistances. The modelling is accompanied by a sensitivity study that addresses the impact of the following matters: the direction of the ice sheet advance, the speed of the ice sheet margin, the bedrock hydraulic and transport properties, the temperature at the ice-subsurface interface close to the ice sheet margin, and the initial hydrochemical conditions.

  5. Optimal control of the process of cultivation in the conditions of infection

    Directory of Open Access Journals (Sweden)

    N. V. Sukhanova

    2016-01-01

    Full Text Available The article presents a way of solving of the optimal control problem of antibiotic feeding under condition of infection, consisting in the selection of the optimal control in the field of admissible control, with the aim of achieving a compromise between the losses in production due to the presence of foreign microflora, and the cost of its suppression due to the application of antibiotic. The presence of other microorganisms in the finished product, in particular of the “wild“ ones, considerably impairs the quality indicators of the final product (in particular, it reduces the storage time. In peculiar conditions of production it is possible to improve the quality of target product due to elimination of infection, including, when used antibiotics in the process of cultivation, but due to the lack of efficient algorithms and control systems of their supply the question is still open. We use the system of Lotka-Volterra adapted for microbiological process as a mathematical model adequately describing the situation of competitive interaction of two populations of microorganisms (useful and “wild“ ones due to the consumption of one resource. The aim is to find a control law U(t belonging to the field of admissible control. The control that affords minimum to the optimization criterion in accordance with the principle of maximum is defined by the condition of the maximum of Hamilton function and the resulting canonical system of equations. The modified conjugated system of equations in matrix form is obtained. The solution of system of differential-different equations in the analytical form is found using the method of coordinate transformation. As a result an optimal control law is found (with regard to the selected criterion. This is the control law of application of the antibiotic, allowing to control the concentration of foreign microflora in the process of cultivation of microorganisms and accounting for the specific

  6. Overview of impurity control and wall conditioning in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    KUGEL,H.W.; MAINGI,R.; BELL,M.; BLANCHARD,W.; GATES,D.; JOHNSON,D.; KAITA,R.; KAYE,S.; MARQUEDA,R.; MENARD,J.; MUELLER,D.; ONO,M.; PENG,Y-K.M.; RAMAN,R.; RAMSEY,A.; ROQUEMORE,A.; SKINNER,C.; SABBAGH,S.; STUTMAN,D.; WAMPLER,WILLIAM R.; WILSON,J.R.; ZWEBEN,S.

    2000-05-25

    The National Spherical Torus Experiment (NSTX) started plasma operations in February 1999, and promptly achieved high current, inner wall limited, double null, and single null plasma discharges, initial Coaxial Helicity Injection, and High Harmonic Fast Wave results. NSTX is designed to study the physics of Spherical Tori (ST) in a device that can produce non-inductively sustained high-{beta} discharges in the 1 MA regime and to explore approaches toward a small, economical high power density ST reactor core. As expected, discharge reproducibility and performance were strongly affected by wall conditions. In this paper, the authors describe the internal geometry, and initial plasma discharge, impurity control, wall conditioning, erosion, and deposition results.

  7. Power systems control complex optimization in the new market conditions

    International Nuclear Information System (INIS)

    Krumm, L.; Kurrel, U.; Tauts, A.; Terno, O.; Zeidmanis, I.; Krisans, Z.

    2000-01-01

    A generalization and development of the theory and methods for complex optimisation of the performance and development control of an interconnected system (IPS) under new market conditions (mainly multicriterial and game approaches) is given considering the specifics of IPS at the international level in post-socialist countries and in particular in the Baltic states. Thereby the kernel of the mathematical apparatus of this theory the Generalized Reduced Gradient Method (GRGM) is further generalised and developed with the application of multicriterial and game methods to meet various market conditions. (author)

  8. Scram characteristics of the control rods of a pressurized water reactor under seismic conditions

    International Nuclear Information System (INIS)

    Fujita, Katsuhisa; Shinohara, Yoshikazu; Nakatogawa, Tetsuto; Nanbu, Kiyoshi; Nomura, Tomonori.

    1987-01-01

    Control rod drop verification experiments of a pressurized water reactor under seismic conditions are performed to confirm the insertion function of control rods into a core. To evaluate these tests, computer simulations are performed. A fuel assembly, control rods, guide tube and other associated structures are immersed in a water tank, and shaken by four hydraulic shakers. The scram time of control rods under seismic conditions was measured, and confirmed to meet the scram function. Moreover, vibrational response characteristics of core structures and dropping behavior of control rods in consideration of collisions are calculated by using a finite difference method. The behavior of the dropping control rods and the scram time obtained by the computer simulation show a very good agreement with the verification experimental results. (author)

  9. Hydrochemical Characteristics and Formation of the Saline or Salty Springs in Eastern Sichuan Basin of China

    Science.gov (United States)

    Zhou, X.

    2017-12-01

    Saline or salty springs provide important information on the hydrogeochemical processes and hydrology within subsurface aquifers. More than 20 saline and salty springs occur in the core of anticlines in the eastern Sichuan Basin in southwestern China where the Lower and Middle Triassic carbonates outcrop. Water samples of 8 saline and salty springs (including one saline hot spring) were collected for analyses of the major and minor constituents, trace elements and stable oxygen and hydrogen isotopes. The TDS of the springs range from 4 to 83 g/L, and they are mainly of Cl-Na type. Sr, Ba and Li are the predominant trace elements. The δ2H and δ18O of the water samples indicate that they are of meteoric origin. The source of salinity of the springs originates from dissolution of minerals in the carbonates, including halite, gypsum, calcite and dolomite. The formation mechanism of the springs is that groundwater receives recharge from infiltration of precipitation, undergoes shallow or deep circulation in the core of the anticline and incongruent dissolution of the salt-bearing carbonates occurs, and emerges in the river valley in the form of springs with relatively high TDS. The 8 springs can be classified into 4 springs of shallow groundwater circulation and 4 springs of deep groundwater circulation according to the depth of groundwater circulation, 7 springs of normal temperature and 1 hot spring according to temperature. There are also 2 up-flow springs: the carbonate aquifers are overlain by relatively impervious sandstone and shale, groundwater may flows up to the ground surface through the local portion of the overlying aquiclude where fractures were relatively well developed, and emerges as an up-flow spring. Knowledge of the hydrochemical characteristics and the geneses of the saline and salty springs are of important significance for the utilization and preservation of the springs.

  10. Understanding the hydrochemical evolution of a coastal dune system in SW England using a multiple tracer technique

    International Nuclear Information System (INIS)

    Allen, Debbie; Darling, W. George; Williams, Peter J.; Stratford, Charlie J.; Robins, Nick S.

    2014-01-01

    Highlights: • Braunton Burrows is an alkaline rain-fed system with no saline intrusion. • Marine aerosols and shell dissolution dominate unsaturated zone water quality. • Hydrochemical evolution in the unsaturated zone is rapid. • Slower evolutionary processes contribute to water quality in the saturated zone. • High dune groundwaters were 13–16 yr old and dune slack groundwater 5–7 yr old. - Abstract: An improved knowledge of the hydrology of coastal dune systems is desirable for successful management of their diverse ecology under a changing climate. As a near-pristine coastal dune spit system, Braunton Burrows (SW England) is an ideal location for the study of the natural processes governing recharge to the dune groundwater system and the evolution of its water quality. Whereas previous investigations have tended to focus on inter-dune slacks, this study has also given attention to infiltration through the high dunes. Cores were taken through dunes and the resulting sand samples processed to provide information on grain size distribution and porewater chemistry. Groundwater samples were obtained from beneath dunes and slacks. A variety of geochemical techniques were applied including hydrochemistry, stable isotopes and residence time indicators. The unsaturated zone profiles indicate the existence of piston flow recharge with an infiltration rate of 0.75–1 m/yr, although faster rates probably also occur locally. Groundwater beneath the high dunes gave ages in the range 13–16 yr, compared to the dune slack groundwater ages of 5–7 yr, and an age of 22 yr for groundwater from the underlying mudstone aquifer. The chemistry of waters in both unsaturated and saturated zones is dominated by Ca and HCO 3 , supplemented by variable amounts of other ions derived from marine aerosols and limited reaction with sand grains and their coatings. The main chemical evolution of the porewaters occurs rapidly through the mobilisation of surface salt crusts and

  11. Experimental study of a novel capacity control algorithm for a multi-evaporator air conditioning system

    International Nuclear Information System (INIS)

    Xu Xiangguo; Pan Yan; Deng Shiming; Xia Liang; Chan Mingyin

    2013-01-01

    The use of a multi-evaporator air conditioning (MEAC) system is advantageous in terms of installation convenience, high design flexibility, being easy to maintain and commission, better indoor thermal comfort control and higher energy efficiency. While MEAC units worth billions of dollars are sold worldwide, the detailed accounts on compressor capacity control and refrigeration flow distribution amongst evaporators remain unavailable in public domain, mainly due to commercial confidentiality. Limited control algorithms for MEAC systems have been developed based on system simulation, and no experimental-based capacity controller developments and their controllability tests may be identified in open literature. In the study reported in this paper, a novel capacity control algorithm, which imitated On–Off control of a single evaporator air conditioning (A/C) system in each indoor unit of a MEAC system by using variable speed compressor and electronic expansion valves (EEVs), was developed. Controllability tests under various settings for experimentally validating the novel capacity control algorithm were carried out and the control algorithm was further improved based on the experimental results. - Highlights: ► A capacity control algorithm for a multi-evaporator air conditioning system was developed. ► Experimental controllability tests under various settings were carried out. ► The control algorithm was further improved based on the experimental results.

  12. Ecohydrological Controls on Intra-Basin Alpine Subarctic Water Balances

    Science.gov (United States)

    Carey, S. K.; Ziegler, C. M.

    2007-12-01

    In the mountainous Canadian subarctic, elevation gradients control the disposition of vegetation, permafrost, and characteristics of the soil profile. How intra-basin ecosystems combine to control catchment-scale water and biogeochimcal cycling is uncertain. To this end, a multi-year ecohydrological investigation was undertaken in Granger Basin (GB), a 7.6 km2 sub-basin of the Wolf Creek Research Basin, Yukon Territory, Canada. GB was divided into four sub-basins based on the dominant vegetation and permafrost status, and the timing and magnitude of hydrological processes were compared using hydrometric and hydrochemical methods. Vegetation plays an important role in end-of-winter snow accumulation as snow redistribution by wind is controlled by roughness length. In sub-basins of GB with tall shrubs, snow accumulation is enhanced compared with areas of short shrubs and tundra vegetation. The timing of melt was staggered with elevation, although melt-rates were similar among the sub-basins. Runoff was enhanced at the expense of infiltration in tall shrub areas due to high snow water equivalent and antecedent soil moisture. In the high-elevation tundra sub-basin, thin soils with cold ground temperatures resulted in increased surface runoff. For the freshet period, the lower and upper sub-basins accounted for 81 % of runoff while accounting for 58 % of the total basin area. Two-component isotopic hydrograph separation revealed that during melt, pre-event water dominated in all sub-basins, yet those with greater permafrost disposition and taller shrubs had increased event-water. Dissolved organic carbon (DOC) spiked prior to peak freshet in each sub-basin except for the highest with thin soils, and was associated with flushing of surficial organic soils. For the post-melt period, all sub-basins have similar runoff contributions. Solute and stable isotope data indicate that in sub-basins dominated by permafrost, supra-permafrost runoff pathways predominate as flow

  13. Necessary optimality conditions of the second oder in a stochastic optimal control problem with delay argument

    Directory of Open Access Journals (Sweden)

    Rashad O. Mastaliev

    2016-12-01

    Full Text Available The optimal control problem of nonlinear stochastic systems which mathematical model is given by Ito stochastic differential equation with delay argument is considered. Assuming that the concerned region is open for the control by the first and the second variation (classical sense of the quality functional we obtain the necessary optimality condition of the first and the second order. In the particular case we receive the stochastic analog of the Legendre—Clebsch condition and some constructively verified conclusions from the second order necessary condition. We investigate the Legendre–Clebsch conditions for the degeneration case and obtain the necessary conditions of optimality for a special control, in the classical sense.

  14. Well Water and Subsurface Salinity of Tuba Basin Langkawi by Hydrochemical Analysis and Vertical Electrical Resistivity Survey

    International Nuclear Information System (INIS)

    Umar Hamzah; Abdul Rahim Samsudin; Abdul Ghani Rafek; Khairul Azlan Razak

    2009-01-01

    Tuba basin is an alluvial deposit located between granitic hill in the western part of Tuba Island and the Setul formation sedimentary rocks in the eastern site of the island. This basin stretched along 3 km in the NE-SW direction with an estimated width of about 2 km. A geophysical survey using geo electrical technique was carried out to figure out the subsurface structure, to detect the presence of underground aquifers and to investigate any saltwater intrusion into these aquifers in the basin. Concentrations of several elements in the well water were also analyzed to investigate any occurrence of salt water intrusion into the coastal aquifers. For this purpose, the vertical electrical sounding surveys were carried out at 22 randomly distributed stations in the study area. Water samples were also taken from 11 wells for hydrochemical analysis in the laboratory. Our results showed that all water samples were of fresh water type. Electrical resistivity profile constructed from stations located in NE-SW direction from Teluk Berembang to Telok Bujur shows a wide range of resistivities ranging from 4 Ωm to infinity. The top layer with a thickness of 1-3 m and resistivity values of 4 - 12 Ωm is interpreted as clay zone. This layer is overlying a much thicker layer of 10-50 m with resistivity values of 2 - 280 Ωm representing sandy material that may contain fresh water or sand with brackish water. Layers with resistivity values from thousands ohm.m to infinity are interpreted as either granite or limestone bedrock. Maximum thickness observed in this resistivity survey is approximately 70 m. (author)

  15. Linear parameter varying control of wind turbines covering both partial load and full load conditions

    DEFF Research Database (Denmark)

    Østergaard, Kasper Zinck; Stoustrup, Jakob; Brath, Per

    2009-01-01

    operations tend to be ill-conditioned. The paper proposes a controller construction algorithm together with various remedies for improving the numerical conditioning the algorithm.The proposed algorithm is applied to the design of a LPV controller for wind turbines, and a comparison is made with a controller...... designed using classical techniques to conclude that an improvement in performance is obtained for the entire operating envelope....

  16. Hydrochemical characteristics of mine waters from abandoned mining sites in Serbia and their impact on surface water quality.

    Science.gov (United States)

    Atanacković, Nebojša; Dragišić, Veselin; Stojković, Jana; Papić, Petar; Zivanović, Vladimir

    2013-11-01

    Upon completion of exploration and extraction of mineral resources, many mining sites have been abandoned without previously putting environmental protection measures in place. As a consequence, mine waters originating from such sites are discharged freely into surface water. Regional scale analyses were conducted to determine the hydrochemical characteristics of mine waters from abandoned sites featuring metal (Cu, Pb-Zn, Au, Fe, Sb, Mo, Bi, Hg) deposits, non-metallic minerals (coal, Mg, F, B) and uranium. The study included 80 mine water samples from 59 abandoned mining sites. Their cation composition was dominated by Ca2+, while the most common anions were found to be SO4(2-) and HCO3-. Strong correlations were established between the pH level and metal (Fe, Mn, Zn, Cu) concentrations in the mine waters. Hierarchical cluster analysis was applied to parameters generally indicative of pollution, such as pH, TDS, SO4(2-), Fe total, and As total. Following this approach, mine water samples were grouped into three main clusters and six subclusters, depending on their potential environmental impact. Principal component analysis was used to group together variables that share the same variance. The extracted principal components indicated that sulfide oxidation and weathering of silicate and carbonate rocks were the primary processes, while pH buffering, adsorption and ion exchange were secondary drivers of the chemical composition of the analyzed mine waters. Surface waters, which received the mine waters, were examined. Analysis showed increases of sulfate and metal concentrations and general degradation of surface water quality.

  17. Success/failure condition influences attribution of control, negative affect, and shame among patients with depression in Singapore.

    Science.gov (United States)

    Yeo, Si-Ning; Zainal, Hani; Tang, Catherine S; Tong, Eddie M; Ho, Cyrus S; Ho, Roger C

    2017-08-02

    There remains a paucity of research on control attribution and depression within Asian populations. This study examines: (1) Success/Failure condition as a moderator between depression and negative affect or shame, and (2) differences in control attribution between patients with depression and healthy controls in Singapore. Seventy one patients with depression and 71 healthy controls went through a digit-span memory task where they were randomized into either the Success or Failure condition. Participants in the Success condition had to memorize and recall 5-digit strings, while participants in the Failure condition did the same for 12-digit strings. They then completed self-report measures of negative affect, shame, and attribution of control. One-way ANCOVA was performed to examine task condition as a moderator of association between mental health status and post-task negative affect or shame. Test of simple effects was carried out on significant interactions. Sign test and Mann-Whitney U test were employed to investigate differences in attribution of control. Mental health status and Success/Failure condition had significant effects on reported negative affect and shame. Healthy controls reported less post-task negative affect and shame in the Success than in the Failure condition while patients with depression reported similar levels of post-task negative affect and shame in both conditions. However, these differences were not significant in the test of simple effects. In addition, healthy controls felt a stronger sense of personal control in success than in failure and were more likely to blame external factors in failure than in success. Conversely, patients with depression were more inclined to credit external factors in success than in failure and ascribed greater personal control in failure than in success. The results suggest that successful conditions may not necessitate the reduction of negative affect in Asians with depression, indicating possible

  18. Rotor experiments in controlled conditions continued: New Mexico

    Science.gov (United States)

    Boorsma, K.; Schepers, J. G.

    2016-09-01

    To validate and reduce the large uncertainty associated with rotor aerodynamic and acoustic models, there is a need for detailed force, noise and surrounding flow velocity measurements on wind turbines under controlled conditions. However, high quality wind tunnel campaigns on horizontal axis wind turbine models are scarce due to the large wind tunnel size needed and consequently high associated costs. To serve this purpose an experiment using the Mexico turbine was set-up in the large low speed facility of the DNW wind tunnel. An overview of the experiments is given including a selection of results. A comparison of calculations to measurements for design conditions shows a satisfactory agreement. In summary, after years of preparation, ECN and partners have performed very successful aerodynamic experiments in the largest wind tunnel in Europe. The comprehensive high quality database that has been obtained will be used in the international Mexnext consortium to further develop wind energy aerodynamic and acoustic modeling.

  19. Unified Subharmonic Oscillation Conditions for Peak or Average Current Mode Control

    OpenAIRE

    Fang, Chung-Chieh

    2013-01-01

    This paper is an extension of the author's recent research in which only buck converters were analyzed. Similar analysis can be equally applied to other types of converters. In this paper, a unified model is proposed for buck, boost, and buck-boost converters under peak or average current mode control to predict the occurrence of subharmonic oscillation. Based on the unified model, the associated stability conditions are derived in closed forms. The same stability condition can be applied to ...

  20. Psychosocial work conditions, unemployment and health locus of control: a population-based study.

    Science.gov (United States)

    Sadiq Mohammad Ali; Lindström, Martin

    2008-06-01

    To investigate the association between psychosocial work conditions, unemployment and lack of belief in the possibility of influencing one's own health. The 2000 public health survey in Scania is a cross-sectional postal questionnaire study with a 59% participation rate. In total, 5180 persons aged 18-64 years who belonged to the workforce and the unemployed were included in this study. Logistic regression models were used to investigate the associations between psychosocial factors at work and unemployment, and lack of belief in the possibility of influencing one's own health (external locus of control). Psychosocial conditions at work were defined according to the Karasek-Theorell demand-control/decision latitudes into relaxed, active, passive, and job strain categories. The multivariate analyses included age, country of birth, education, economic stress, and social participation. In total, 26.6% of all men and 26.9% of all women lack an internal locus of control. The passive, job strain and unemployed categories have significantly higher odds ratios of lack of internal locus of control, as compared to the relaxed reference category. No such significant differences are observed for the active category. These patterns remain in the multivariate models, with the exception of the passive and unemployed categories among men, in which the significant differences disappear. Psychosocial work conditions and unemployment may affect health locus of control. The control dimension in the Karasek-Theorell model seems to be of greatest importance.

  1. From conservative to reactive transport under diffusion-controlled conditions

    Science.gov (United States)

    Babey, Tristan; de Dreuzy, Jean-Raynald; Ginn, Timothy R.

    2016-05-01

    We assess the possibility to use conservative transport information, such as that contained in transit time distributions, breakthrough curves and tracer tests, to predict nonlinear fluid-rock interactions in fracture/matrix or mobile/immobile conditions. Reference simulated data are given by conservative and reactive transport simulations in several diffusive porosity structures differing by their topological organization. Reactions includes nonlinear kinetically controlled dissolution and desorption. Effective Multi-Rate Mass Transfer models (MRMT) are calibrated solely on conservative transport information without pore topology information and provide concentration distributions on which effective reaction rates are estimated. Reference simulated reaction rates and effective reaction rates evaluated by MRMT are compared, as well as characteristic desorption and dissolution times. Although not exactly equal, these indicators remain very close whatever the porous structure, differing at most by 0.6% and 10% for desorption and dissolution. At early times, this close agreement arises from the fine characterization of the diffusive porosity close to the mobile zone that controls fast mobile-diffusive exchanges. At intermediate to late times, concentration gradients are strongly reduced by diffusion, and reactivity can be captured by a very limited number of rates. We conclude that effective models calibrated solely on conservative transport information like MRMT can accurately estimate monocomponent kinetically controlled nonlinear fluid-rock interactions. Their relevance might extend to more advanced biogeochemical reactions because of the good characterization of conservative concentration distributions, even by parsimonious models (e.g., MRMT with 3-5 rates). We propose a methodology to estimate reactive transport from conservative transport in mobile-immobile conditions.

  2. Hyperglycemic conditions inhibit C3-mediated immunologic control of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Hair Pamela S

    2012-03-01

    Full Text Available Abstract Background Diabetic patients are at increased risk for bacterial infections; these studies provide new insight into the role of the host defense complement system in controlling bacterial pathogens in hyperglycemic environments. Methods The interactions of complement C3 with bacteria in elevated glucose were assayed for complement activation to opsonic forms, phagocytosis and bacterial killing. C3 was analyzed in euglycemic and hyperglycemic conditions by mass spectrometry to measure glycation and structural differences. Results Elevated glucose inhibited S. aureus activation of C3 and deposition of C3b and iC3b on the bacterial surface. S. aureus-generated C5a and serum-mediated phagocytosis by neutrophils were both decreased in elevated glucose conditions. Interestingly, elevated glucose increased the binding of unactivated C3 to S. aureus, which was reversible on return to normal glucose concentrations. In a model of polymicrobial infection, S. aureus in elevated glucose conditions depleted C3 from serum resulting in decreased complement-mediated killing of E. coli. To investigate the effect of differing glucose concentration on C3 structure and glycation, purified C3 incubated with varying glucose concentrations was analyzed by mass spectrometry. Glycation was limited to the same three lysine residues in both euglycemic and hyperglycemic conditions over one hour, thus glycation could not account for observed changes between glucose conditions. However, surface labeling of C3 with sulfo-NHS-biotin showed significant changes in the surface availability of seven lysine residues in response to increasing glucose concentrations. These results suggest that the tertiary structure of C3 changes in response to hyperglycemic conditions leading to an altered interaction of C3 with bacterial pathogens. Conclusions These results demonstrate that hyperglycemic conditions inhibit C3-mediated complement effectors important in the immunological

  3. Theoretical Background for the Decision-Making Process Modelling under Controlled Intervention Conditions

    OpenAIRE

    Bakanauskienė Irena; Baronienė Laura

    2017-01-01

    This article is intended to theoretically justify the decision-making process model for the cases, when active participation of investing entities in controlling the activities of an organisation and their results is noticeable. Based on scientific literature analysis, a concept of controlled conditions is formulated, and using a rational approach to the decision-making process, a model of the 11-steps decision-making process under controlled intervention is presented. Also, there have been u...

  4. Control of Root Rot and Wilt Diseases of Roselle under Field Conditions

    Science.gov (United States)

    Hassan, Naglaa; Elsharkawy, Mohsen Mohamed; Shimizu, Masafumi

    2014-01-01

    Roselle (Hibiscus sabdariffa L.) is one of the most important medicinal crops in many parts of the world. In this study, the effects of microelements, antioxidants, and bioagents on Fusarium oxysporum, F. solani, and Macrophomina phaseolina, the causal pathogens of root rot and wilt diseases in roselle, were examined under field conditions. Preliminary studies were carried out in vitro in order to select the most effective members to be used in field control trials. Our results showed that microelements (copper and manganese), antioxidants (salicylic acid, ascorbic acid, and EDTA), a fungicide (Dithane M45) and biological control agents (Trichoderma harzianum and Bacillus subtilis) were significantly reduced the linear growth of the causal pathogens. Additionally, application of the previous microelements, antioxidants, a fungicide and biological control agents significantly reduced disease incidence of root rot and wilt diseases under field conditions. Copper, salicylic acid, and T. harzianum showed the best results in this respect. In conclusion, microelements, antioxidants, and biocontrol agents could be used as alternative strategies to fungicides for controlling root rot and wilt diseases in roselle. PMID:25606010

  5. Hydrochemical determination of source water contributions to Lake Lungo and Lake Ripasottile (central Italy

    Directory of Open Access Journals (Sweden)

    Claire Archer

    2016-12-01

    Full Text Available Lake Lungo and Lake Ripasottile are two shallow (4-5 m lakes located in the Rieti Basin, central Italy, that have been described previously as surface outcroppings of the groundwater table. In this work, the two lakes as well as springs and rivers that represent their potential source waters are characterized physio-chemically and isotopically, using a combination of environmental tracers. Temperature and pH were measured and water samples were analyzed for alkalinity, major ion concentration, and stable isotope (δ2H, δ18O, δ13C of dissolved inorganic carbon, and δ34S and δ18O of sulfate composition.  Chemical data were also investigated in terms of local meteorological data (air temperature, precipitation to determine the sensitivity of lake parameters to changes in the surrounding environment. Groundwater represented by samples taken from Santa Susanna Spring was shown to be distinct with SO42- and Mg2+ content of 270 and 29 mg/L, respectively, and heavy sulfate isotopic composition (δ34S=15.2 ‰ and δ18O=10‰. Outflow from the Santa Susanna Spring enters Lake Ripasottile via a canal and both spring and lake water exhibits the same chemical distinctions and comparatively low seasonal variability. Major ion concentrations in Lake Lungo are similar to the Vicenna Riara Spring and are interpreted to represent the groundwater locally recharged within the plain. The δ13CDIC exhibit the same groupings as the other chemical parameters, providing supporting evidence of the source relationships. Lake Lungo exhibited exceptional ranges of δ13CDIC (±5 ‰ and δ2H, δ18O (±5 ‰ and ±7 ‰, respectively, attributed to sensitivity to seasonal changes. The hydrochemistry results, particularly major ion data, highlight how the two lakes, though geographically and morphologically similar, represent distinct hydrochemical facies. These data also show a different response in each lake to temperature and precipitation patterns in the basin that

  6. Adaptive Neural Control of Nonaffine Nonlinear Systems without Differential Condition for Nonaffine Function

    Directory of Open Access Journals (Sweden)

    Chaojiao Sun

    2016-01-01

    Full Text Available An adaptive neural control scheme is proposed for nonaffine nonlinear system without using the implicit function theorem or mean value theorem. The differential conditions on nonaffine nonlinear functions are removed. The control-gain function is modeled with the nonaffine function probably being indifferentiable. Furthermore, only a semibounded condition for nonaffine nonlinear function is required in the proposed method, and the basic idea of invariant set theory is then constructively introduced to cope with the difficulty in the control design for nonaffine nonlinear systems. It is rigorously proved that all the closed-loop signals are bounded and the tracking error converges to a small residual set asymptotically. Finally, simulation examples are provided to demonstrate the effectiveness of the designed method.

  7. Modeling and fuzzy control of the engine coolant conditioning system in an IC engine test bed

    International Nuclear Information System (INIS)

    Mohtasebi, Seyed Saeid; Shirazi, Farzad A.; Javaheri, Ahmad; Nava, Ghodrat Hamze

    2010-01-01

    Mechanical and thermodynamical performance of internal combustion engines is significantly affected by the engine working temperature. In an engine test bed, the internal combustion engines are tested in different operating conditions using a dynamometer. It is required that the engine temperature be controlled precisely, particularly in transient states. This precise control can be achieved by an engine coolant conditioning system mainly consisting of a heat exchanger, a control valve, and a controller. In this study, constitutive equations of the system are derived first. These differential equations show the second- order nonlinear time-varying dynamics of the system. The model is validated with the experimental data providing satisfactory results. After presenting the dynamic equations of the system, a fuzzy controller is designed based on our prior knowledge of the system. The fuzzy rules and the membership functions are derived by a trial and error and heuristic method. Because of the nonlinear nature of the system the fuzzy rules are set to satisfy the requirements of the temperature control for different operating conditions of the engine. The performance of the fuzzy controller is compared with a PI one for different transient conditions. The results of the simulation show the better performance of the fuzzy controller. The main advantages of the fuzzy controller are the shorter settling time, smaller overshoot, and improved performance especially in the transient states of the system

  8. Simplified model-based optimal control of VAV air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Nassif, N.; Kajl, S.; Sabourin, R. [Ecole de Technologie Superieure, Montreal, PQ (Canada). Dept. of Construction Engineering

    2005-07-01

    The improvement of Variable Air Volume (VAV) system performance is one of several attempts being made to minimize the high energy use associated with the operation of heating, ventilation and air conditioning (HVAC) systems. A Simplified Optimization Process (SOP) comprised of controller set point strategies and a simplified VAV model was presented in this paper. The aim of the SOP was to determine supply set points. The advantage of the SOP over previous methods was that it did not require a detailed VAV model and optimization program. In addition, the monitored data for representative local-loop control can be checked on-line, after which controller set points can be updated in order to ensure proper operation by opting for real situations with minimum energy use. The SOP was validated using existing monitoring data and a model of an existing VAV system. Energy use simulations were compared to that of the existing VAV system. At each simulation step, 3 controller set point values were proposed and studied using the VAV model in order to select a value for each point which corresponded to the best performance of the VAV system. Simplified VAV component models were presented. Strategies for controller set points were described, including zone air temperature, duct static pressure set points; chilled water supply set points and supply air temperature set points. Simplified optimization process calculations were presented. Results indicated that the SOP provided significant energy savings when applied to specific AHU systems. In a comparison with a Detailed Optimization Process (DOP), the SOP was capable of determining set points close to those obtained by the DOP. However, it was noted that the controller set points determined by the SOP need a certain amount of time to reach optimal values when outdoor conditions or thermal loads are significantly changed. It was suggested that this disadvantage could be overcome by the use of a dynamic incremental value, which

  9. Towards energy efficient operation of Heating, Ventilation and Air Conditioning systems via advanced supervisory control design

    Science.gov (United States)

    Oswiecinska, A.; Hibbs, J.; Zajic, I.; Burnham, K. J.

    2015-11-01

    This paper presents conceptual control solution for reliable and energy efficient operation of heating, ventilation and air conditioning (HVAC) systems used in large volume building applications, e.g. warehouse facilities or exhibition centres. Advanced two-level scalable control solution, designed to extend capabilities of the existing low-level control strategies via remote internet connection, is presented. The high-level, supervisory controller is based on Model Predictive Control (MPC) architecture, which is the state-of-the-art for indoor climate control systems. The innovative approach benefits from using passive heating and cooling control strategies for reducing the HVAC system operational costs, while ensuring that required environmental conditions are met.

  10. Simulation Evaluation of Controller-Managed Spacing Tools under Realistic Operational Conditions

    Science.gov (United States)

    Callantine, Todd J.; Hunt, Sarah M.; Prevot, Thomas

    2014-01-01

    Controller-Managed Spacing (CMS) tools have been developed to aid air traffic controllers in managing high volumes of arriving aircraft according to a schedule while enabling them to fly efficient descent profiles. The CMS tools are undergoing refinement in preparation for field demonstration as part of NASA's Air Traffic Management (ATM) Technology Demonstration-1 (ATD-1). System-level ATD-1 simulations have been conducted to quantify expected efficiency and capacity gains under realistic operational conditions. This paper presents simulation results with a focus on CMS-tool human factors. The results suggest experienced controllers new to the tools find them acceptable and can use them effectively in ATD-1 operations.

  11. Computation of reactor control rod drop time under accident conditions

    International Nuclear Information System (INIS)

    Dou Yikang; Yao Weida; Yang Renan; Jiang Nanyan

    1998-01-01

    The computational method of reactor control rod drop time under accident conditions lies mainly in establishing forced vibration equations for the components under action of outside forces on control rod driven line and motion equation for the control rod moving in vertical direction. The above two kinds of equations are connected by considering the impact effects between control rod and its outside components. Finite difference method is adopted to make discretization of the vibration equations and Wilson-θ method is applied to deal with the time history problem. The non-linearity caused by impact is iteratively treated with modified Newton method. Some experimental results are used to validate the validity and reliability of the computational method. Theoretical and experimental testing problems show that the computer program based on the computational method is applicable and reliable. The program can act as an effective tool of design by analysis and safety analysis for the relevant components

  12. Bio boiler - Control conditions. Part 1: Model development and analysis of operating conditions; Biokedel - Reguleringsmaessige forhold. Del 1: Modeludvikling og analyse af dynamiske driftsforhold

    Energy Technology Data Exchange (ETDEWEB)

    Boecher Poulsen, K.; Christensen, Torkild; Mortensen, Jan; Runge Kristoffersen, J.; Kristmundsson, E. [Tech-wise A/S (Denmark); Moekbak, T.; Mortensen, Hans Peter [Elsam A/S (Denmark)

    2002-12-15

    This report focuses on the model-building part of the PSO project, 'Control Conditions Bio-boiler'. In the project, which treats dynamic simulation of biomass fired power plants via the MMS software, a certain number of straw/wood chip modules have been built, together with a combustion module which, when connected to the existing MMS modules, can be used for dynamic simulation. Furthermore, a certain number of continuous and discrete components have been built which, together with the remaining MMS modules will create a complete model of the active part of the control structure under the most common operation conditions. By means of the developed straw, combustion and control modules, a model of Enstedvaerket's bio-boiler is built (without wood chip super-heater), including practically all auxiliary control mechanisms. In the report the primary problems caused by the development of the model are discussed, typically numerical problems. First of all it is discussed how a steady state condition can be reached from a nonphysical condition at the start-up of the simulation. After reaching a steady state condition at full load, the boiler load is reduced by adjusting the desired live steam flow setpoint value and the load gradient (as it would be done from the control room). While reducing to part load, one straw line is closed down, as it would be done in 'real life'. From part load, the boiler load is once again in the same way increased to full. (BA) The simulation results are then compared to measurements made on the same boiler during load reduction and load increase.

  13. Sector-condition-based results for adaptive control and synchronization of chaotic systems under input saturation

    International Nuclear Information System (INIS)

    Iqbal, Muhammad; Rehan, Muhammad; Hong, Keum-Shik; Khaliq, Abdul; Saeed-ur-Rehman

    2015-01-01

    This paper addresses the design of adaptive feedback controllers for two problems (namely, stabilization and synchronization) of chaotic systems with unknown parameters by considering input saturation constraints. A novel generalized sector condition is developed to deal with the saturation nonlinearities for synthesizing the nonlinear and the adaptive controllers for the stabilization and synchronization control objectives. By application of the proposed sector condition and rigorous regional stability analysis, control and adaptation laws are formulated to guarantee local stabilization of a nonlinear system under actuator saturation. Further, simple control and adaptation laws are developed to synchronize two chaotic systems under uncertain parameters and input saturation nonlinearity. Numerical simulation results for Rössler and FitzHugh–Nagumo models are provided to demonstrate the effectiveness of the proposed adaptive stabilization and synchronization control methodologies

  14. Hydrochemical characteristics and quality assessment of deep groundwater from the coal-bearing aquifer of the Linhuan coal-mining district, Northern Anhui Province, China.

    Science.gov (United States)

    Lin, Man-Li; Peng, Wei-Hua; Gui, He-Rong

    2016-04-01

    There is little information available about the hydrochemical characteristics of deep groundwater in the Linhuan coal-mining district, Northern Anhui Province, China. In this study, we report information about the physicochemical parameters, major ions, and heavy metals of 17 groundwater samples that were collected from the coal-bearing aquifer. The results show that the concentrations of total dissolved solids, electrical conductivity, and potassium and sodium (K(+) + Na(+)) in most of the groundwater samples exceeded the guidelines of the World Health Organization (WHO) and the Chinese National Standards for Drinking Water Quality (GB 5749-2006). The groundwater from the coal-bearing aquifer was dominated by the HCO3·Cl-K + Na and HCO3·SO4-K + Na types. Analysis with a Gibbs plot suggested that the major ion chemistry of the groundwater was primarily controlled by weathering of rocks and that the coal-bearing aquifer in the Linhuan coal-mining district was a relatively closed system. K(+) and Na(+) originated from halite and silicate weathering reactions, while Ca(2+) and Mg(2+) originated from the dissolution of calcite, dolomite, and gypsum or anhydrite. Ion exchange reactions also had an influence on the formation of major ions in groundwater. The concentrations of selected heavy metals decreased in the order Mn > Zn > Cr > Cu > Ni > Pb. In general, the heavy metal concentrations were low; however, the Cr, Mn, and Ni concentrations in some of the groundwater samples exceeded the standards outlined by the WHO, the GB 5749-2006, and the Chinese National Standards for Groundwater (GB/T 14848-93). Analysis by various indices (% Na, SAR, and EC), a USSL diagram, and a Wilcox diagram showed that both the salinity and alkalinity of the groundwater were high, such that the groundwater could not be used for irrigating agricultural land without treatment. These results will be significant for water resource exploiting and utilization in

  15. A high control bandwidth design method for aalborg inverter under weak grid condition

    DEFF Research Database (Denmark)

    Wu, Weimin; Zhou, Cong; Wang, Houqin

    2017-01-01

    Aalborg Inverter is a kind of high efficient Buck-Boost inverter. Since it may work in “Buck-Boost” mode, the control bandwidth should be high enough to ensure a good performance under any grid condition. However, during the “Boost” operation, the control bandwidth depends much on the grid...

  16. Quantitative trait loci associated with longevity of lettuce seeds under conventional and controlled deterioration storage conditions.

    Science.gov (United States)

    Schwember, Andrés R; Bradford, Kent J

    2010-10-01

    Lettuce (Lactuca sativa L.) seeds have poor shelf life and exhibit thermoinhibition (fail to germinate) above ∼25°C. Seed priming (controlled hydration followed by drying) alleviates thermoinhibition by increasing the maximum germination temperature, but reduces lettuce seed longevity. Controlled deterioration (CD) or accelerated ageing storage conditions (i.e. elevated temperature and relative humidity) are used to study seed longevity and to predict potential seed lifetimes under conventional storage conditions. Seeds produced in 2002 and 2006 of a recombinant inbred line (RIL) population derived from a cross between L. sativa cv. Salinas×L. serriola accession UC96US23 were utilized to identify quantitative trait loci (QTLs) associated with seed longevity under CD and conventional storage conditions. Multiple longevity-associated QTLs were identified under both conventional and CD storage conditions for control (non-primed) and primed seeds. However, seed longevity was poorly correlated between the two storage conditions, suggesting that deterioration processes under CD conditions are not predictive of ageing in conventional storage conditions. Additionally, the same QTLs were not identified when RIL populations were grown in different years, indicating that lettuce seed longevity is strongly affected by production environment. Nonetheless, a major QTL on chromosome 4 [Seed longevity 4.1 (Slg4.1)] was responsible for almost 23% of the phenotypic variation in viability of the conventionally stored control seeds of the 2006 RIL population, with improved longevity conferred by the Salinas allele. QTL analyses may enable identification of mechanisms responsible for the sensitivity of primed seeds to CD conditions and breeding for improved seed longevity.

  17. Thermophysical Properties Measurement of High-Temperature Liquids Under Microgravity Conditions in Controlled Atmospheric Conditions

    Science.gov (United States)

    Watanabe, Masahito; Ozawa, Shumpei; Mizuno, Akotoshi; Hibiya, Taketoshi; Kawauchi, Hiroya; Murai, Kentaro; Takahashi, Suguru

    2012-01-01

    Microgravity conditions have advantages of measurement of surface tension and viscosity of metallic liquids by the oscillating drop method with an electromagnetic levitation (EML) device. Thus, we are preparing the experiments of thermophysical properties measurements using the Materials-Science Laboratories ElectroMagnetic-Levitator (MSL-EML) facilities in the international Space station (ISS). Recently, it has been identified that dependence of surface tension on oxygen partial pressure (Po2) must be considered for industrial application of surface tension values. Effect of Po2 on surface tension would apparently change viscosity from the damping oscillation model. Therefore, surface tension and viscosity must be measured simultaneously in the same atmospheric conditions. Moreover, effect of the electromagnetic force (EMF) on the surface oscillations must be clarified to obtain the ideal surface oscillation because the EMF works as the external force on the oscillating liquid droplets, so extensive EMF makes apparently the viscosity values large. In our group, using the parabolic flight levitation experimental facilities (PFLEX) the effect of Po2 and external EMF on surface oscillation of levitated liquid droplets was systematically investigated for the precise measurements of surface tension and viscosity of high temperature liquids for future ISS experiments. We performed the observation of surface oscillations of levitated liquid alloys using PFLEX on board flight experiments by Gulfstream II (G-II) airplane operated by DAS. These observations were performed under the controlled Po2 and also under the suitable EMF conditions. In these experiments, we obtained the density, the viscosity and the surface tension values of liquid Cu. From these results, we discuss about as same as reported data, and also obtained the difference of surface oscillations with the change of the EMF conditions.

  18. Model predictions and control of conditions in a CA-reefer container

    NARCIS (Netherlands)

    Sman, van der R.G.M.; Verdijck, G.J.C.

    2003-01-01

    In this paper a concept for energy saving for refrigerated container transport is presented. The concept is based on model-predictive control of the set points of the cooling unit. These models predict energy consumption of the cooling unit, climatic conditions inside the cargo space, and the change

  19. The comparison respond of braking torque control between PID and SMC controller for electric powered wheelchair descending on slope condition

    Science.gov (United States)

    Asyraf, S. M.; Heerwan, P. M.; Izhar, I. M.

    2018-04-01

    During descending on a slope, the speed of Electric Powered Wheelchair (EPW) tends to changed rapidly. Normally, most EPW is provided with mechanical braking system which transfers human pulling force of the lever creating friction at the tire. However, the task is difficult for the users are elderly or paralyses. However, even for normal user with good strength, in fear condition they tend to give sudden braking which leads to tire locking up and skidding, eventually EPW unstable. These problems will cause accident and injuries to the users if speed does not properly control. In this paper, the automated braking torque control method was proposed in EPW as alternative to solve this problem and increase the mobility and stability especially during descending on slope in other to help the user of the EPW as their daily transportation. In this research, Proportional-Integral-Derivative and Sliding Mode Control controller are compared to determine the best response for torque braking control. The rapid change of speed can be controlled by the braking torque using proposed controllers based on the desired constant speed set by the control designer. Moreover, the sudden braking that caused tire to lock up and skid can be avoided. Furthermore, result from SMC shows this controller have good time respond to maintain the speed based on desired value when descending at slope condition by controlling the braking torque compared to the PID controller.

  20. 77 FR 57039 - Special Conditions: Embraer S.A., Model EMB-550 Airplane; Electronic Flight Control System...

    Science.gov (United States)

    2012-09-17

    ... Flight Control System: Control Surface Awareness and Mode Annunciation AGENCY: Federal Aviation... a fly-by-wire electronic flight control system and no direct coupling from the flightdeck controller... nuisance alerting. This special condition also addresses flight control system mode annunciation. It...

  1. Radiation risks and monitoring of transboundary rivers of Kazakhstan

    International Nuclear Information System (INIS)

    Kadyrzhanov, K.K.; Solodukhin, V.P.; Khazhekber, S.; Poznyak, V.L.; Chernykh, E.E.; Passell, H.D.

    2006-01-01

    Full text: The condition of the water resources of the Republic of Kazakhstan is characterized with their whole deficiency as well as their high pollution and desiccation. The situation is also aggravated with much relaxation of work coordination on regulation of trans-boundary river flows and control of their water quality as a result of the USSR collapse and isolation of separate republics. The absence of objective information on water condition of rivers and their contamination sources creates a danger of high ecological risk and psychological stress for inhabitants, localities of that related to the basins of these rivers, and serves as reasoning for claims (occasionally unreasonable) to neighboring countries. Following rivers are the largest trans-boundary ones in Kazakhstan: Ile, Syrdarya, Ural and Irtysh. All these rivers are of great importance for people's life-support of the republic. At the same time presence of a number of large industrial centers, agricultural enterprises and radiation-dangerous objects in the basins of these rivers creates a potential danger of chemical and radiation contamination for their water flows. Objective information on its influence rate is required. The most acceptable form of the control of radiation and hydro-chemical situation in the basins of transboundary rivers is their monitoring based on modern nuclear-and-physical methods of analysis. Very important factor in organization of such monitoring system is participation of all the countries concerned with the basin of the river under the control. There is a work experience of many years in Central Asia on monitoring of large Syrdarya and Amudarya rivers. These works have been carried out since 2000 with the framework of the International project NAVRUZ. Participants of this project are organizations of nuclear profile from Uzbekistan, Kirghizia, Tajikistan and Kazakhstan. The collaborator of this project is the Sandia National Laboratories (SNL), USA. Experience of these

  2. Controlled cooling of an electronic system based on projected conditions

    Science.gov (United States)

    David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

    2015-08-18

    Energy efficient control of a cooling system cooling an electronic system is provided based, in part, on projected conditions. The control includes automatically determining an adjusted control setting(s) for an adjustable cooling component(s) of the cooling system. The automatically determining is based, at least in part, on projected power consumed by the electronic system at a future time and projected temperature at the future time of a heat sink to which heat extracted is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on an experimentally obtained model(s) relating the targeted temperature and power consumption of the adjustable cooling component(s) of the cooling system.

  3. Hydrochemical evidence for mixing of river water and groundwater during high-flow conditions, lower Suwannee River basin, Florida, USA

    Science.gov (United States)

    Crandall, C.A.; Katz, B.G.; Hirten, J.J.

    1999-01-01

    Karstic aquifers are highly susceptible to rapid infiltration of river water, particularly during periods of high flow. Following a period of sustained rainfall in the Suwannee River basin, Florida, USA, the stage of the Suwannee River rose from 3.0 to 5.88 m above mean sea level in April 1996 and discharge peaked at 360 m3/s. During these high-flow conditions, water from the Suwannee River migrated directly into the karstic Upper Floridan aquifer, the main source of water supply for the area. Changes in the chemical composition of groundwater were quantified using naturally occurring geochemical tracers and mass-balance modeling techniques. Mixing of river water with groundwater was indicated by a decrease in the concentrations of calcium, silica, and 222Rn; and by an increase in dissolved organic carbon (DOC), tannic acid, and chloride, compared to low-flow conditions in water from a nearby monitoring well, Wingate Sink, and Little River Springs. The proportion (fraction) of river water in groundwater ranged from 0.13 to 0.65 at Wingate Sink and from 0.5 to 0.99 at well W-17258, based on binary mixing models using various tracers. The effectiveness of a natural tracer in quantifying mixing of river water and groundwater was related to differences in tracer concentration of the two end members and how conservatively the tracer reacted in the mixed water. Solutes with similar concentrations in the two end-member waters (Na, Mg, K, Cl, SO4, SiO2) were not as effective tracers for quantifying mixing of river water and groundwater as those with larger differences in end-member concentrations (Ca, tannic acid, DOC, 222Rn, HCO3). ?? Springer-Verlag.

  4. General collaboration offer of Johnson Controls regarding the performance of air conditioning automatic control systems and other buildings` automatic control systems

    Energy Technology Data Exchange (ETDEWEB)

    Gniazdowski, J.

    1995-12-31

    JOHNSON CONTROLS manufactures measuring and control equipment (800 types) and is as well a {open_quotes}turn-key{close_quotes} supplier of complete automatic controls systems for heating, air conditioning, ventilation and refrigerating engineering branches. The Company also supplies Buildings` Computer-Based Supervision and Monitoring Systems that may be applied in both small and large structures. Since 1990 the company has been performing full-range trade and contracting activities on the Polish market. We have our own well-trained technical staff and we collaborate with a series of designing and contracting enterprises that enable us to have our projects carried out all over Poland. The prices of our supplies and services correspond with the level of the Polish market.

  5. Boundary-Layer Separation Control under Low-Pressure Turbine Airfoil Conditions using Glow-Discharge Plasma Actuators

    Science.gov (United States)

    Hultgren, Lennart S.; Ashpis, David E.

    2003-01-01

    Modem low-pressure turbines, in general, utilize highly loaded airfoils in an effort to improve efficiency and to lower the number of airfoils needed. Typically, the airfoil boundary layers are turbulent and fully attached at takeoff conditions, whereas a substantial fraction of the boundary layers on the airfoils may be transitional at cruise conditions due to the change of density with altitude. The strong adverse pressure gradients on the suction side of these airfoils can lead to boundary-layer separation at the latter low Reynolds number conditions. Large separation bubbles, particularly those which fail to reattach, cause a significant degradation of engine efficiency. A component efficiency drop of the order 2% may occur between takeoff and cruise conditions for large commercial transport engines and could be as large as 7% for smaller engines at higher altitude. An efficient means of of separation elimination/reduction is, therefore, crucial to improved turbine design. Because the large change in the Reynolds number from takeoff to cruise leads to a distinct change in the airfoil flow physics, a separation control strategy intended for cruise conditions will need to be carefully constructed so as to incur minimum impact/penalty at takeoff. A complicating factor, but also a potential advantage in the quest for an efficient strategy, is the intricate interplay between separation and transition for the situation at hand. Volino gives a comprehensive discussion of several recent studies on transition and separation under low-pressure-turbine conditions, among them one in the present facility. Transition may begin before or after separation, depending on the Reynolds number and other flow conditions. If the transition occurs early in the boundary layer then separation may be reduced or completely eliminated. Transition in the shear layer of a separation bubble can lead to rapid reattachment. This suggests using control mechanisms to trigger and enhance early

  6. Cooling water conditioning and quality control for tokamaks

    International Nuclear Information System (INIS)

    Gootgeld, A.M.

    1995-10-01

    Designers and operators of Tokamaks and all associated water cooled, peripheral equipment, are faced with the task of providing and maintaining closed-loop, low conductivity, low impurity, cooling water systems. Most of these systems must provide large volumes of high quality cooling water at reasonable cost and comply with local and state government orders and EPA mandated national pretreatment standards and regulations. This paper discusses the DIII-D water quality requirements, the means used to obtain the necessary quality and the instrumentation used for control and monitoring. Costs to mechanically and chemically condition and maintain water quality are discussed as well as the various aspects of complying with government standards and regulations

  7. Deep aquifer systems in the molasse basin of South-West Germany. Thorough hydrogeological study as a basis for a future quantitative an qualitative management

    International Nuclear Information System (INIS)

    Watzel, R.; Bertleff, B.

    1996-01-01

    The sandstone basin of the south of Germany is an area where the geothermic exploitation is intensive. The well-working of these equipments require good attainments about the quantities of available water in the aquifer stratum and about the geometric conditions. That is the reason why the rest part of the basin has been largely prospected for almost twenty years. Hydraulic, hydro-chemical and isotopic studies have shown that two circulation zones have to be differentiated. Very different replacement conditions are represented in the latter. The possibilities of geometric exploitations are determined by the ratio of the paleo-Pleistocene aquiferous stratum and of the recently formed one. This study handles above all with the results of the hydro-chemical and isotopic exams and with the issue of the renewal of the aquiferous stratum. The possible consequences for the future use of the stratum will be outlined. (authors). 61 refs., 6 figs

  8. Conditionally controlling nuclear trafficking in yeast by chemical-induced protein dimerization.

    Science.gov (United States)

    Xu, Tao; Johnson, Cole A; Gestwicki, Jason E; Kumar, Anuj

    2010-11-01

    We present here a protocol to conditionally control the nuclear trafficking of target proteins in yeast. In this system, rapamycin is used to heterodimerize two chimeric proteins. One chimera consists of a FK506-binding protein (FKBP12) fused to a cellular 'address' (nuclear localization signal or nuclear export sequence). The second chimera consists of a target protein fused to a fluorescent protein and the FKBP12-rapamycin-binding (FRB) domain from FKBP-12-rapamycin associated protein 1 (FRAP1, also known as mTor). Rapamycin induces dimerization of the FKBP12- and FRB-containing chimeras; these interactions selectively place the target protein under control of the cell address, thereby directing the protein into or out of the nucleus. By chemical-induced dimerization, protein mislocalization is reversible and enables the identification of conditional loss-of-function and gain-of-function phenotypes, in contrast to other systems that require permanent modification of the targeted protein. Yeast strains for this analysis can be constructed in 1 week, and the technique allows protein mislocalization within 15 min after drug treatment.

  9. Conditions for the existence of control functions in nonseparable simultaneous equations models

    OpenAIRE

    Blundell, Richard; Matzkin, Rosa L.

    2010-01-01

    The control function approach (Heckman and Robb (1985)) in a system of linear simultaneous equations provides a convenient procedure to estimate one of the functions in the system using reduced form residuals from the other functions as additional regressors. The conditions on the structural system under which this procedure can be used in nonlinear and nonparametric simultaneous equations has thus far been unknown. In this note, we define a new property of functions called control function s...

  10. Controlling the site density of multiwall carbon nanotubes via growth conditions

    Science.gov (United States)

    Siegal, M. P.; Overmyer, D. L.; Kaatz, F. H.

    2004-06-01

    We present two complementary methods for controlling the site density of multiwall carbon nanotubes (CNTs) directly as a function of growth conditions from 1011to107CNTs/cm2. Several potential applications require significant spacing between individual CNTs. The first method shows that the site density varies with the heat of formation of the hydrocarbon gas used during CNT growth by thermal chemical vapor deposition. The second method demonstrates that the site density decreases with increasing residual stress of the metal catalyst/diffusion barrier layers. These methods are combined for wide-range control of CNT site density.

  11. Energy Analysis for Air Conditioning System Using Fuzzy Logic Control

    Directory of Open Access Journals (Sweden)

    Henry Nasution

    2011-04-01

    Full Text Available Reducing energy consumption and to ensure thermal comfort are two important considerations for the designing an air conditioning system. An alternative approach to reduce energy consumption proposed in this study is to use a variable speed compressor. The control strategy will be proposed using the fuzzy logic controller (FLC. FLC was developed to imitate the performance of human expert operators by encoding their knowledge in the form of linguistic rules. The system is installed on a thermal environmental room with a data acquisition system to monitor the temperature of the room, coefficient of performance (COP, energy consumption and energy saving. The measurements taken during the two hour experimental periods at 5-minutes interval times for temperature setpoints of 20oC, 22oC and 24oC with internal heat loads 0, 500, 700 and 1000 W. The experimental results indicate that the proposed technique can save energy in comparison with On/Off and proportional-integral-derivative (PID control.

  12. Hydrothermal and hydrochemical operating conditions of the cooling water basin of the Lithuanian thermalelectric station. Gidrotermicheskii i gidrokhimicheskii rezhim vodokhranilishcha - okhladitela Litovskoi GRES

    Energy Technology Data Exchange (ETDEWEB)

    Lasinskas, M

    1981-01-01

    Complex studies of the cooling water storage basin and its drainage system are described. Physical and geographical conditions (terrain, soil, vegetation, etc) of the drainage system and their influence on processes within the water basin are discussed. Inflow and discharge parts of the water balance, particularly the evaporation of hot water from the basin surface, are discussed. Data of long-term measurements of thermal conditions, heat exchange processes and their relation to the effectivity of the thermalelectric plant are presented. Heat balance of the water basin was determined. The influence of the Lithuanian Hydro upon precipitation, physical and chemical operating conditions of the water storage basin, and drainage and ground water was studied. The characteristics of the chemical composition of bottom sediments, intensity of current sedimentation processes and sediment accumulation in the water storage basin are given.

  13. Assessing the hydrogeochemical processes affecting groundwater pollution in arid areas using an integration of geochemical equilibrium and multivariate statistical techniques

    International Nuclear Information System (INIS)

    El Alfy, Mohamed; Lashin, Aref; Abdalla, Fathy; Al-Bassam, Abdulaziz

    2017-01-01

    Rapid economic expansion poses serious problems for groundwater resources in arid areas, which typically have high rates of groundwater depletion. In this study, integration of hydrochemical investigations involving chemical and statistical analyses are conducted to assess the factors controlling hydrochemistry and potential pollution in an arid region. Fifty-four groundwater samples were collected from the Dhurma aquifer in Saudi Arabia, and twenty-one physicochemical variables were examined for each sample. Spatial patterns of salinity and nitrate were mapped using fitted variograms. The nitrate spatial distribution shows that nitrate pollution is a persistent problem affecting a wide area of the aquifer. The hydrochemical investigations and cluster analysis reveal four significant clusters of groundwater zones. Five main factors were extracted, which explain >77% of the total data variance. These factors indicated that the chemical characteristics of the groundwater were influenced by rock–water interactions and anthropogenic factors. The identified clusters and factors were validated with hydrochemical investigations. The geogenic factors include the dissolution of various minerals (calcite, aragonite, gypsum, anhydrite, halite and fluorite) and ion exchange processes. The anthropogenic factors include the impact of irrigation return flows and the application of potassium, nitrate, and phosphate fertilizers. Over time, these anthropogenic factors will most likely contribute to further declines in groundwater quality. - Highlights: • Hydrochemical investigations were carried out in Dhurma aquifer in Saudi Arabia. • The factors controlling potential groundwater pollution in an arid region were studied. • Chemical and statistical analyses are integrated to assess these factors. • Five main factors were extracted, which explain >77% of the total data variance. • The chemical characteristics of the groundwater were influenced by rock–water interactions

  14. Mitigating cutaneous sensation differences during tDCS: comparing sham versus low intensity control conditions.

    Science.gov (United States)

    Brunyé, Tad T; Cantelon, Julie; Holmes, Amanda; Taylor, Holly A; Mahoney, Caroline R

    2014-01-01

    Cutaneous sensations at electrode sites during the administration of direct current brain stimulation may inadvertently influence participants' subjective experience and task performance. The present study evaluated the utility of a methodological variation that substitutes sham administration with very low intensity (0.5 mA) current delivery. We used a 4 × 1 high-definition ring electrode transcranial direct current (HD-tDCS) system to target the left dorsolateral prefrontal cortex (Brodmann's Area 9). Four stimulation conditions were compared in a repeated-measures design: sham 2.0 mA and 0.5 mA intensity, versus active 2.0 mA and 0.5 mA intensity. During stimulation participants performed a cognitive interference task that activates the cingulo-frontal-parietal network, and periodically provided perceived sensation ratings. We demonstrate that a relatively low intensity control condition attenuates otherwise large differences in perceived sensation between active and sham conditions. Critically, behavioral task differences maintained between the two active conditions. A low intensity control stimulation condition may prove a viable methodological alternative to conventional sham techniques used in repeated-measures designs, though important limitations are discussed. Published by Elsevier Inc.

  15. Energy Savings and Economics of Advanced Control Strategies for Packaged Air-Conditioning Units with Gas Heat

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Weimin; Katipamula, Srinivas; Huang, Yunzhi; Brambley, Michael R.

    2011-12-31

    Pacific Northwest National Laboratory (PNNL) with funding from the U.S. Department of Energy's Building Technologies Program (BTP) evaluated a number of control strategies that can be implemented in a controller, to improve the operational efficiency of the packaged air conditioning units. The two primary objectives of this research project are: (1) determine the magnitude of energy savings achievable by retrofitting existing packaged air conditioning units with advanced control strategies not ordinarily used for packaged units and (2) estimating what the installed cost of a replacement control with the desired features should be in various regions of the U.S. This document reports results of the study.

  16. Hydrochemical characterization of groundwater in the Akyem area, Ghana

    Science.gov (United States)

    Banoeng-Yakubo, B.; Yidana, S.M.; Anku, Y.; Akabzaa, T.; Asiedu, D.

    2008-01-01

    The Akyem area is a small farming community located in southeastern Ghana. Groundwater samples from wells in the area were analyzed for concentrations of the major ions, silica, electrical conductivity and pH. The objective was to determine the main controls on the hydrochemistry of ground-water. Mass balance modeling was used together with multivariate R-mode hierarchical cluster analysis to determine the significant sources of variation in the hydrochemistry. Two water types exist in this area. The first is influenced most by the weathering of silicate minerals from the underlying geology, and is thus rich in silica, sodium, calcium, bicarbonate, and magnesium ions. The second is water that has been influenced by the effects of fertilizers and other anthropogenic activities in the area. Mineral speciation and silicate mineral stability diagrams suggest that montmorillonite, probably derived from the incongruent dissolution of feldspars and micas, is the most stable silicate phase in the groundwaters. The apparent incongruent weathering of silicate minerals in the groundwater system has led to the enrichment of sodium, calcium, magnesium and bicarbonate ions as well as silica, leading to the supersaturation of calcite, aragonite, dolomite and quartz. Stability in the montmorillonite field suggests restricted flow conditions and a long groundwater residence time, leading to greater exposure of the rock to weathering. Cation exchange processes appear to play minor roles in the hydrochemistry of groundwater.

  17. The Effects of Fluency Enhancing Conditions on Sensorimotor Control of Speech in Typically Fluent Speakers: An EEG Mu Rhythm Study

    Directory of Open Access Journals (Sweden)

    Tiffani Kittilstved

    2018-04-01

    Full Text Available Objective: To determine whether changes in sensorimotor control resulting from speaking conditions that induce fluency in people who stutter (PWS can be measured using electroencephalographic (EEG mu rhythms in neurotypical speakers.Methods: Non-stuttering (NS adults spoke in one control condition (solo speaking and four experimental conditions (choral speech, delayed auditory feedback (DAF, prolonged speech and pseudostuttering. Independent component analysis (ICA was used to identify sensorimotor μ components from EEG recordings. Time-frequency analyses measured μ-alpha (8–13 Hz and μ-beta (15–25 Hz event-related synchronization (ERS and desynchronization (ERD during each speech condition.Results: 19/24 participants contributed μ components. Relative to the control condition, the choral and DAF conditions elicited increases in μ-alpha ERD in the right hemisphere. In the pseudostuttering condition, increases in μ-beta ERD were observed in the left hemisphere. No differences were present between the prolonged speech and control conditions.Conclusions: Differences observed in the experimental conditions are thought to reflect sensorimotor control changes. Increases in right hemisphere μ-alpha ERD likely reflect increased reliance on auditory information, including auditory feedback, during the choral and DAF conditions. In the left hemisphere, increases in μ-beta ERD during pseudostuttering may have resulted from the different movement characteristics of this task compared with the solo speaking task. Relationships to findings in stuttering are discussed.Significance: Changes in sensorimotor control related feedforward and feedback control in fluency-enhancing speech manipulations can be measured using time-frequency decompositions of EEG μ rhythms in neurotypical speakers. This quiet, non-invasive, and temporally sensitive technique may be applied to learn more about normal sensorimotor control and fluency enhancement in PWS.

  18. Controls of multi-modal wave conditions in a complex coastal setting

    Science.gov (United States)

    Hegermiller, Christie; Rueda, Ana C.; Erikson, Li H.; Barnard, Patrick L.; Antolinez, J.A.A.; Mendez, Fernando J.

    2017-01-01

    Coastal hazards emerge from the combined effect of wave conditions and sea level anomalies associated with storms or low-frequency atmosphere-ocean oscillations. Rigorous characterization of wave climate is limited by the availability of spectral wave observations, the computational cost of dynamical simulations, and the ability to link wave-generating atmospheric patterns with coastal conditions. We present a hybrid statistical-dynamical approach to simulating nearshore wave climate in complex coastal settings, demonstrated in the Southern California Bight, where waves arriving from distant, disparate locations are refracted over complex bathymetry and shadowed by offshore islands. Contributions of wave families and large-scale atmospheric drivers to nearshore wave energy flux are analyzed. Results highlight the variability of influences controlling wave conditions along neighboring coastlines. The universal method demonstrated here can be applied to complex coastal settings worldwide, facilitating analysis of the effects of climate change on nearshore wave climate.

  19. Anti-seismic air condition's cooling capability increase of the second control area

    International Nuclear Information System (INIS)

    Pan Qiang

    2008-01-01

    Secondary area (SCA) air-conditioning system is an important ventilation system in plant. It should achieve the indoor temperature controllable. To resolve the problem of cooling capacity insufficiency, on the basis of ventilation and refrigeration theory, the thesis analyzes the design modification plan. (author)

  20. Wall conditioning and particle control in Extrap T2

    Science.gov (United States)

    Bergsåker, H.; Larsson, D.; Brunsell, P.; Möller, A.; Tramontin, L.

    1997-02-01

    The Extrap T2 reversed field pinch experiment is operated with the former OHTE vacuum vessel, of dimensions R = 1.24 m and a = 0.18 m and with a complete graphite liner. It is shown that a rudimentary density control can be achieved by means of frequent helium glow discharge conditioning of the wall. The standard He-GDC is well characterized and reproducible. The trapping and release of hydrogen and impurities at the wall surfaces have been studied by mass spectrometry and surface analysis. The shot to shot particle exchange between wall and plasma can be approximately accounted for.

  1. Flap controllers applied on the OffshoreWindChina (OWC) 5MW reference wind turbine for Chinese typhoon conditions

    DEFF Research Database (Denmark)

    Barlas, Athanasios

    The report describes the development of flap controllers applied on the OffshoreWindChina (OWC) 5MW reference wind turbine for Chinese typhoon conditions. Optimal flap controllers are designed and tuned based on linear aeroelastic models from HawcStab2. The controllers are evaluated in normal......, parked and storm conditions, targeting the alleviation of fatigue and extreme loads....

  2. Assessment of the State of the Art of Flight Control Technologies as Applicable to Adverse Conditions

    Science.gov (United States)

    Reveley, Mary s.; Briggs, Jeffrey L.; Leone, Karen M.; Kurtoglu, Tolga; Withrow, Colleen A.

    2010-01-01

    Literature from academia, industry, and other Government agencies was surveyed to assess the state of the art in current Integrated Resilient Aircraft Control (IRAC) aircraft technologies. Over 100 papers from 25 conferences from the time period 2004 to 2009 were reviewed. An assessment of the general state of the art in adaptive flight control is summarized first, followed by an assessment of the state of the art as applicable to 13 identified adverse conditions. Specific areas addressed in the general assessment include flight control when compensating for damage or reduced performance, retrofit software upgrades to flight controllers, flight control through engine response, and finally test and validation of new adaptive controllers. The state-of-the-art assessment applicable to the adverse conditions include technologies not specifically related to flight control, but may serve as inputs to a future flight control algorithm. This study illustrates existing gaps and opportunities for additional research by the NASA IRAC Project

  3. Verification of the karst flow model under laboratory controlled conditions

    Science.gov (United States)

    Gotovac, Hrvoje; Andric, Ivo; Malenica, Luka; Srzic, Veljko

    2016-04-01

    Karst aquifers are very important groundwater resources around the world as well as in coastal part of Croatia. They consist of extremely complex structure defining by slow and laminar porous medium and small fissures and usually fast turbulent conduits/karst channels. Except simple lumped hydrological models that ignore high karst heterogeneity, full hydraulic (distributive) models have been developed exclusively by conventional finite element and finite volume elements considering complete karst heterogeneity structure that improves our understanding of complex processes in karst. Groundwater flow modeling in complex karst aquifers are faced by many difficulties such as a lack of heterogeneity knowledge (especially conduits), resolution of different spatial/temporal scales, connectivity between matrix and conduits, setting of appropriate boundary conditions and many others. Particular problem of karst flow modeling is verification of distributive models under real aquifer conditions due to lack of above-mentioned information. Therefore, we will show here possibility to verify karst flow models under the laboratory controlled conditions. Special 3-D karst flow model (5.6*2.6*2 m) consists of concrete construction, rainfall platform, 74 piezometers, 2 reservoirs and other supply equipment. Model is filled by fine sand (3-D porous matrix) and drainage plastic pipes (1-D conduits). This model enables knowledge of full heterogeneity structure including position of different sand layers as well as conduits location and geometry. Moreover, we know geometry of conduits perforation that enable analysis of interaction between matrix and conduits. In addition, pressure and precipitation distribution and discharge flow rates from both phases can be measured very accurately. These possibilities are not present in real sites what this model makes much more useful for karst flow modeling. Many experiments were performed under different controlled conditions such as different

  4. Fuel conditioning facility zone-to-zone transfer administrative controls

    International Nuclear Information System (INIS)

    Pope, C. L.

    2000-01-01

    The administrative controls associated with transferring containers from one criticality hazard control zone to another in the Argonne National Laboratory (ANL) Fuel Conditioning Facility (FCF) are described. FCF, located at the ANL-West site near Idaho Falls, Idaho, is used to remotely process spent sodium bonded metallic fuel for disposition. The process involves nearly forty widely varying material forms and types, over fifty specific use container types, and over thirty distinct zones where work activities occur. During 1999, over five thousand transfers from one zone to another were conducted. Limits are placed on mass, material form and type, and container types for each zone. Ml material and containers are tracked using the Mass Tracking System (MTG). The MTG uses an Oracle database and numerous applications to manage the database. The database stores information specific to the process, including material composition and mass, container identification number and mass, transfer history, and the operators involved in each transfer. The process is controlled using written procedures which specify the zone, containers, and material involved in a task. Transferring a container from one zone to another is called a zone-to-zone transfer (ZZT). ZZTs consist of four distinct phases, select, request, identify, and completion

  5. Hydrogen-control systems for severe LWR accident conditions - a state-of-technology report

    International Nuclear Information System (INIS)

    Hilliard, R.K.; Postma, A.K.; Jeppson, D.W.

    1983-03-01

    This report reviews the current state of technology regarding hydrogen safety issues in light water reactor plants. Topics considered in this report relate to control systems and include combustion prevention, controlled combustion, minimization of combustion effects, combination of control concepts, and post-accident disposal. A companion report addresses hydrogen generation, distribution, and combustion. The objectives of the study were to identify the key safety issues related to hydrogen produced under severe accident conditions, to describe the state of technology for each issue, and to point out ongoing programs aimed at resolving the open issues

  6. Single room control for user-optimised room air conditions; Einzelraumregelung fuer nutzungsoptimiertes Raumklima

    Energy Technology Data Exchange (ETDEWEB)

    Lezius, A. [Staefa Control System GmbH, Leinfelden-Echterdingen (Germany)

    1995-12-31

    In chapter 14 of the anthology about building control the single room control for achieving user-optimised room air conditions is described. The following aspects are discussed: What is comfort? What is economic efficiency? Systems for secondary air treatment, adapted functions of the measurement and control technique, management functions, orientation of the demand at the use, investment and amortisation. (BWI) [Deutsch] Kapitel 14 des Sammelbandes ueber Building control ist dem Thema der Einzelraumregelung zur Erzielung eines nutzungsoptimierten Raumklimas gewidmet. In diesem Zusammenhang werden folgende Themenbereiche angesprochen: Was ist Komfort? Was ist Wirtschaftlichkeit? Systeme fuer sekundaere Luftbehandlung; Angepasste Funktionen der MSR-Technik; Managementfunktionen; Bedarfsorientierung an der Nutzung; Investition und Amortisation. (BWI)

  7. An Operation Control Strategy for the Connected Maglev Trains Based on Vehicle-Borne Battery Condition Monitoring

    Directory of Open Access Journals (Sweden)

    Wenjing Zhang

    2018-01-01

    Full Text Available Vehicle-borne battery condition is an important factor affecting the efficiency of the maglev train operation and other connected ones. To effectively eliminate the influence of the battery condition and improve the operation efficiency of the connected maglev trains, an operation control strategy is proposed to guarantee train operation safety. First, based on Internet of Things, a sensor network is designed to monitor vehicle-borne battery condition in each vehicle of the train. Second, the train Operation Control System collects battery data of all vehicles in a maglev train by Train Communication Network. Third, all connected maglev trains share the battery data via a 38 GHz directional Radio Communication System and adjust operation control strategy accordingly. Simulation results indicate that the proposed strategy can guarantee the operation safety of the connected maglev trains.

  8. Hydrochemistry of shallow groundwater and surface water in the ...

    African Journals Online (AJOL)

    judevom

    chemical characteristics of the water,. (2) define the factors that control major ion chemistry, and (3) evaluate their suitability for drinking and irrigation. The data will provide a hydrochemical baseline data for water quality assessment, management, ...

  9. Hydrochemical tracers in the middle Rio Grande Basin, USA: 1. Conceptualization of groundwater flow

    Science.gov (United States)

    Plummer, L. Niel; Bexfield, Laura M.; Anderholm, Scott K.; Sanford, Ward E.; Busenberg, Eurybiades

    Chemical and isotopic data for groundwater from throughout the Middle Rio Grande Basin, central New Mexico, USA, were used to identify and map groundwater flow from 12 sources of water to the basin, evaluate radiocarbon ages, and refine the conceptual model of the Santa Fe Group aquifer system. Hydrochemical zones, representing groundwater flow over thousands to tens of thousands of years, can be traced over large distances through the primarily siliciclastic aquifer system. The locations of the hydrochemical zones mostly reflect the ``modern'' predevelopment hydraulic-head distribution, but are inconsistent with a trough in predevelopment water levels in the west-central part of the basin, indicating that this trough is a transient rather than a long-term feature of the aquifer system. Radiocarbon ages adjusted for geochemical reactions, mixing, and evapotranspiration/dilution processes in the aquifer system were nearly identical to the unadjusted radiocarbon ages, and ranged from modern to more than 30 ka. Age gradients from piezometer nests ranged from 0.1 to 2 year cm-1 and indicate a recharge rate of about 3 cm year-1 for recharge along the eastern mountain front and infiltration from the Rio Grande near Albuquerque. There has been appreciably less recharge along the eastern mountain front north and south of Albuquerque. Des données sur les éléments chimiques et les isotopes présents dans l'eau souterraine prélevée à divers endroits dans le bassin moyen du Rio Grande, au centre du Nouveau-Mexique (É-U), ont permis de déterminer l'existence et l'étendue de douze sources d'eau régionales dans le bassin, d'évaluer les âges radiocarbones et de raffiner le modèle conceptuel du système aquifère du groupe de Santa Fe. Des zones hydro-chimiques qui représentent l'écoulement de l'eau souterraine depuis des dizaines de milliers d'années peuvent être suivies sur de longues distances à travers l'aquifère principalement siliclastique. La position des

  10. Estimation of The Contribution of the Water Sources in The Mixed Waters; Karisim Sularinda Koekensel Katkilarin Belirlenmesi

    Energy Technology Data Exchange (ETDEWEB)

    Kurttas, T [Hacettepe University, Ankara (Turkey)

    2002-07-01

    In many cases simple hydrogeochemical evaluations are sufficient to distinguish different source of the waters in the hydrogeological studies. In this study how hydrochemical data can be used to understand mixing mechanism is explained. Mixing ratios determined by using physically or chemically nonreactive component in hydrogeological studies. For mixing quantity calculations, quantity of the end members that cause to mixing, need to be known. Electrical conductivity is another parameter may be used when lack of hydrochemical data is present or more practical and fast solution is required. Isotope techniques are widely used to describe the hydrogeological conditions, where the conventional methods is not sufficient to understand. Since {sup 18}O ve D are conservative isotopes and do not effected by the hydrochemical processes in the aquifer, they are used to explain recharge quantities of the aquifer, determination of the recharge areas, groundwater-surface water relations, determination of mixing quantities and understanding of recharge-discharge relations in the fractured aquifers. By using stable isotope data, sources of the mixing portions, dissolution of salts, evaporation and isotopic enrichment or fresh water-salt water/fresh water- sea water mixing can be identified easily.

  11. Duct corrosion in the ventilating air conditioning system for Main Control Room

    International Nuclear Information System (INIS)

    Yamada, Kohei; Kobayashi, Takashi; Minami, Akiko; Fukuba, Kazushi

    2014-01-01

    Higashidori Nuclear Power Station, start-of-operation in December 2005, is a relatively new plant. We decided to get original data of air duct condition to determine maintenance policy of air duct, because planned maintenance of air duct has never been done and the corrosion of air duct has occurred in other plant. In January 2014, we found a corrosion-hole at the downstream of the inlet damper in the ventilating air conditioning system for Main Control Room (MCR). We supposed that the cause of rapid corrosion is related to the characteristic environment of this site. (author)

  12. Online optimal control of variable refrigerant flow and variable air volume combined air conditioning system for energy saving

    International Nuclear Information System (INIS)

    Zhu, Yonghua; Jin, Xinqiao; Du, Zhimin; Fang, Xing

    2015-01-01

    The variable refrigerant flow (VRF) and variable air volume (VAV) combined air conditioning system can solve the problem of the VRF system in outdoor air ventilation while taking advantage of its high part load energy efficiency. Energy performance of the combined air conditioning system can also be optimized by joint control of both the VRF and the VAV parts. A model-based online optimal control strategy for the combined air conditioning system is presented. Simplified adaptive models of major components of the combined air conditioning system are firstly developed for predicting system performances. And a cost function in terms of energy consumption and thermal comfort is constructed. Genetic algorithm is used to search for the optimal control sets. The optimal control strategy is tested and evaluated through two case studies based on the simulation platform. Results show that the optimal strategy can effectively reduce energy consumption of the combined air conditioning system while maintaining acceptable thermal comfort. - Highlights: • A VRF and VAV combined system is proposed. • A model-based online optimal control strategy is proposed for the combined system. • The strategy can reduce energy consumption without sacrificing thermal comfort. • Novel simplified adaptive models are firstly developed for the VRF system

  13. Responses of hydrochemical inorganic ions in the rainfall-runoff processes of the experimental catchments and its significance for tracing

    Science.gov (United States)

    Gu, W.-Z.; Lu, J.-J.; Zhao, X.; Peters, N.E.

    2007-01-01

    Aimed at the rainfall-runoff tracing using inorganic ions, the experimental study is conducted in the Chuzhou Hydrology Laboratory with special designed experimental catchments, lysimeters, etc. The various runoff components including the surface runoff, interflow from the unsaturated zone and the groundwater flow from saturated zone were monitored hydrometrically. Hydrochemical inorganic ions including Na+, K+, Ca2+, Mg2+, Cl-, SO42-, HCO3- + CO32-, NO3-, F-, NH4-, PO42-, SiO2 and, pH, EC, 18O were measured within a one month period for all processes of rainfall, various runoff components and groundwater within the catchment from 17 boreholes distributed in the Hydrohill Catchment, few soil water samples were also included. The results show that: (a) all the runoff components are distinctly identifiable from both the relationships of Ca2+ versus Cl-/SO42-, EC versus Na+/(Na+ + Ca2+) and, from most inorganic ions individually; (b) the variation of inorganic ions in surface runoff is the biggest than that in other flow components; (c) most ions has its lowermost concentration in rainfall process but it increases as the generation depths of runoff components increased; (d) quantitatively, ion processes of rainfall and groundwater flow display as two end members of that of other runoff components; and (e) the 18O processes of rainfall and runoff components show some correlation with that of inorganic ions. The results also show that the rainfall input is not always the main source of inorganic ions of various runoff outputs due to the process of infiltration and dissolution resulted from the pre-event processes. The amount and sources of Cl- of runoff components with various generation mechanisms challenge the current method of groundwater recharge estimation using Cl-.

  14. Second-Order Necessary Optimality Conditions for Some State-Constrained Control Problems of Semilinear Elliptic Equations

    International Nuclear Information System (INIS)

    Casas, E.; Troeltzsch, F.

    1999-01-01

    In this paper we are concerned with some optimal control problems governed by semilinear elliptic equations. The case of a boundary control is studied. We consider pointwise constraints on the control and a finite number of equality and inequality constraints on the state. The goal is to derive first- and second-order optimality conditions satisfied by locally optimal solutions of the problem

  15. Vector-valued measure and the necessary conditions for the optimal control problems of linear systems

    International Nuclear Information System (INIS)

    Xunjing, L.

    1981-12-01

    The vector-valued measure defined by the well-posed linear boundary value problems is discussed. The maximum principle of the optimal control problem with non-convex constraint is proved by using the vector-valued measure. Especially, the necessary conditions of the optimal control of elliptic systems is derived without the convexity of the control domain and the cost function. (author)

  16. Integral Plus Resonant Sliding Mode Direct Power Control for VSC-HVDC Systems under Unbalanced Grid Voltage Conditions

    Directory of Open Access Journals (Sweden)

    Weipeng Yang

    2017-10-01

    Full Text Available An integral plus resonant sliding mode direct power control (IRSMC DPC strategy for voltage source converter high voltage direct current (VSC-HVDC systems under unbalanced grid voltage conditions is proposed in this paper. Through detailed instantaneous power flow analysis, a generalized power compensation method, by which the ratio between the amplitude of active and reactive power ripples can be controlled continuously, is obtained. This enables the system to provide flexible power control, so that the desired performance of the system on both the ac and dc sides can be attained under different operating conditions. When the grid voltage is unbalanced, one or both of the active and reactive power terms contain ripples, oscillating at twice the grid frequency, to obtain non-distorted ac current. A power controller consisting of the proportional, integral and resonant control laws is designed using the sliding mode control approach, to achieve accurate power control objective. Simulation studies on a two-terminal VSC-HVDC system using MATLAB/SIMULINK (R2013b, Mathworks, Natick, MA, USA are conducted to verify the effectiveness of the IRSMC DPC strategy. The results show that this strategy ensures satisfactory performance of the system over a wide range of operating conditions.

  17. Performance Evaluation of UPQC under Nonlinear Unbalanced Load Conditions Using Synchronous Reference Frame Based Control

    Science.gov (United States)

    Kota, Venkata Reddy; Vinnakoti, Sudheer

    2017-12-01

    Today, maintaining Power Quality (PQ) is very important in the growing competent world. With new equipments and devices, new challenges are also being put before power system operators. Unified Power Quality Conditioner (UPQC) is proposed to mitigate many power quality problems and to improve the performance of the power system. In this paper, an UPQC with Fuzzy Logic controller for capacitor voltage balancing is proposed in Synchronous Reference Frame (SRF) based control with Modified Phased Locked Loop (MPLL). The proposed controller with SRF-MPLL based control is tested under non-linear and unbalanced load conditions. The system is developed in Matlab/Simulink and its performance is analyzed under various conditions like non-linear, unbalanced load and polluted supply voltage including voltage sag/swells. Active and reactive power flow in the system, power factor and %THD of voltages and currents before and after compensation are also analyzed in this work. Results prove the applicability of the proposed scheme for power quality improvement. It is observed that the fuzzy controller gives better performance than PI controller with faster capacitor voltage balancing and also improves the dynamic performance of the system.

  18. Non-contact control of the working condition of mechanical units of the steam compressor for desalination plant

    Science.gov (United States)

    Danilin, A. I.; Chernyavsky, A. Zh.; Danilin, S. A.; Neverov, V. V.; Voroh, D. A.; Blagin, E. V.

    2018-03-01

    New methods and means for monitoring working condition of the rotating elements of steam compressor unit such as blade ring of the impeller and gears of multiplier are considered. Blade control is carried out by the signalling device of pre-emergency deformation of impeller blades. Control of the gears condition is carried out by apparatus system which allows to analyse change of the signal form caused by the gears wear. Influence of the wear types on the typical information parameters of the analysed signals is described. Technical characteristics of the devices and experimental research results are presented. Described control systems allow to detect deviations equal to 1-2% from initial condition. Application of such systems gives the opportunity to improve fault diagnosis and maintenance in 2-3 times.

  19. 78 FR 76254 - Special Conditions: Airbus, Model A350-900 Series Airplane; Control Surface Awareness and Mode...

    Science.gov (United States)

    2013-12-17

    ...-0899; Notice No. 25-13-15-SC] Special Conditions: Airbus, Model A350-900 Series Airplane; Control... of proposed special conditions. SUMMARY: This action proposes special conditions for the Airbus Model..., data, or views. The most helpful comments reference a specific portion of the proposed special...

  20. Approximate controllability of a semilinear elliptic problem with Robin condition in a periodically perforated domain

    Directory of Open Access Journals (Sweden)

    Nikita Agarwal

    2017-07-01

    Full Text Available In this article, we study the approximate controllability and homegenization results of a semi-linear elliptic problem with Robin boundary condition in a periodically perforated domain. We prove the existence of minimal norm control using Lions constructive approach, which is based on Fenchel-Rockafeller duality theory, and by means of Zuazua's fixed point arguments. Then, as the homogenization parameter goes to zero, we link the limit of the optimal controls (the limit of fixed point of the controllability problems with the optimal control of the corresponding homogenized problem.

  1. Postural Control Can Be Well Maintained by Healthy, Young Adults in Difficult Visual Task, Even in Sway-Referenced Dynamic Conditions.

    Science.gov (United States)

    Lions, Cynthia; Bucci, Maria Pia; Bonnet, Cédrick

    2016-01-01

    To challenge the validity of existing cognitive models of postural control, we recorded eye movements and postural sway during two visual tasks (a control free-viewing task and a difficult searching task), and two postural tasks (one static task in which the platform was maintained stable and a dynamic task in which the platform moved in a sway-referenced manner.) We expected these models to be insufficient to predict the results in postural control both in static-as already shown in the literature reports-and in dynamic platform conditions. Twelve healthy, young adults (17.3 to 34.1 years old) participated in this study. Postural performances were evaluated using the Multitest platform (Framiral®) and ocular recording was performed with Mobile T2 (e(ye)BRAIN®). In the free-viewing task, the participants had to look at an image, without any specific instruction. In the searching task, the participants had to look at an image and also to locate the position of an object in the scene. Postural sway was only significantly higher in the dynamic free-viewing condition than in the three other conditions with no significant difference between these three other conditions. Visual task performance was slightly higher in dynamic than in static conditions. As expected, our results did not confirm the main assumption of the current cognitive models of postural control-i.e. that the limited attentional resources of the brain should explain changes in postural control in our conditions. Indeed, 1) the participants did not sway significantly more in the sway-referenced dynamic searching condition than in any other condition; 2) the participants swayed significantly less in both static and dynamic searching conditions than in the dynamic free-viewing condition. We suggest that a new cognitive model illustrating the adaptive, functional role of the brain to control upright stance is necessary for future studies.

  2. Postural Control Can Be Well Maintained by Healthy, Young Adults in Difficult Visual Task, Even in Sway-Referenced Dynamic Conditions.

    Directory of Open Access Journals (Sweden)

    Cynthia Lions

    Full Text Available To challenge the validity of existing cognitive models of postural control, we recorded eye movements and postural sway during two visual tasks (a control free-viewing task and a difficult searching task, and two postural tasks (one static task in which the platform was maintained stable and a dynamic task in which the platform moved in a sway-referenced manner. We expected these models to be insufficient to predict the results in postural control both in static-as already shown in the literature reports-and in dynamic platform conditions.Twelve healthy, young adults (17.3 to 34.1 years old participated in this study. Postural performances were evaluated using the Multitest platform (Framiral® and ocular recording was performed with Mobile T2 (e(yeBRAIN®. In the free-viewing task, the participants had to look at an image, without any specific instruction. In the searching task, the participants had to look at an image and also to locate the position of an object in the scene.Postural sway was only significantly higher in the dynamic free-viewing condition than in the three other conditions with no significant difference between these three other conditions. Visual task performance was slightly higher in dynamic than in static conditions.As expected, our results did not confirm the main assumption of the current cognitive models of postural control-i.e. that the limited attentional resources of the brain should explain changes in postural control in our conditions. Indeed, 1 the participants did not sway significantly more in the sway-referenced dynamic searching condition than in any other condition; 2 the participants swayed significantly less in both static and dynamic searching conditions than in the dynamic free-viewing condition. We suggest that a new cognitive model illustrating the adaptive, functional role of the brain to control upright stance is necessary for future studies.

  3. Remote Supervision and Control of Air Conditioning Systems in Different Modes

    Science.gov (United States)

    Rafeeq, Mohammed; Afzal, Asif; Rajendra, Sree

    2018-01-01

    In the era of automation, most of the application of engineering and science are interrelated with system for optimal operation. To get the efficient result of an operation and desired response, interconnected systems should be controlled by directing, regulating and commanding. Here, air conditioning (AC) system is considered for experimentation, to supervise and control its functioning in both, automated and manual mode. This paper reports the work intended to design and develop an automated and manual AC system working in remote and local mode, to increase the level of comfort, easy operation, reducing human intervention and faults occurring in the system. The Programmable Logical Controller (PLC) and Supervisory Control and Data Acquisition (SCADA) system were used for remote supervision and monitoring of AC systems using series ninety protocol and remote terminal unit modbus protocol as communication module to operate in remote mode. PLC was used as remote terminal for continuous supervision and control of AC system. SCADA software was used as a tool for designing user friendly graphical user interface. The proposed SCADA AC system successfully monitors and controls in accordance within the parameter limits like temperature, pressure, humidity and voltage. With all the features, this designed system is capable of efficient handling of the resources like the compressor, humidifier etc., with all the levels of safety and durability. This system also maintains the temperature and controls the humidity of the remote location and also looks after the health of the compressor.

  4. Enhanced Decoupled Double Synchronous Reference Frame Current Controller for Unbalanced Grid-Voltage Conditions

    DEFF Research Database (Denmark)

    Reyes, M.; Rodriguez, Pedro; Vazquez, S.

    2012-01-01

    . In these codes, the injection of positive- and negative-sequence current components becomes necessary for fulfilling, among others, the low-voltage ride-through requirements during balanced and unbalanced grid faults. However, the performance of classical dq current controllers, applied to power converters......, under unbalanced grid-voltage conditions is highly deficient, due to the unavoidable appearance of current oscillations. This paper analyzes the performance of the double synchronous reference frame controller and improves its structure by adding a decoupling network for estimating and compensating...

  5. A power conditioning system for thermoelectric generator based on interleaved Boost converter with MPPT control

    DEFF Research Database (Denmark)

    Ni, L.-X; Sun, K.; Zhang, L.

    2011-01-01

    The thermoelectric generation (TEG) system has its special charactristics of high stablility, low voltage and high current output, which is different from PV modules. The power conditioning system and control schemes used in PV applications cannot be directly applied to TEG applications. A power...... conditioning system for TEG based on interleaved Boost converter with maximum power point tracking (MPPT) control is investigated in this paper. Since an internal resistance exists inside TEG modules, an improved perturbation and observation (P&O) MPPT control scheme with power limit is proposed to extract...... maximum power from TEG by matching the load with internal resistance. Since the battery is usually employed as the load for TEG systems, the interleaved Boost converter operates in two different modes for battery charging: before the battery is fully charged, the system outputs the maximum power (MPPT...

  6. Start-up conditions and the performance of women - and men - controlled businesses in manufacturing industries

    Directory of Open Access Journals (Sweden)

    Otilia Driga

    2010-01-01

    Full Text Available Recent research into the economic performance of women-controlled firms suggests that their underperformance may not be the result of differences in the managerial ability of women as compared to men, and that it may in fact be a consequence of differing levels of start-up resources. Using accounting data, we examine the effects that selected start-up conditions have had on the observed economic performance of a sample of 4450 Spanish manufacturing firms. The results, which indicate significant differences in the initial conditions and show lower levels of assets and employee numbers in women-controlled firms, have implications for the economic performance of such firms.

  7. Comparative Analysis of Maximum Power Point Tracking Controllers under Partial Shaded Conditions in a Photovoltaic System

    Directory of Open Access Journals (Sweden)

    R. Ramaprabha

    2015-06-01

    Full Text Available Mismatching effects due to partial shaded conditions are the major drawbacks existing in today’s photovoltaic (PV systems. These mismatch effects are greatly reduced in distributed PV system architecture where each panel is effectively decoupled from its neighboring panel. To obtain the optimal operation of the PV panels, maximum power point tracking (MPPT techniques are used. In partial shaded conditions, detecting the maximum operating point is difficult as the characteristic curves are complex with multiple peaks. In this paper, a neural network control technique is employed for MPPT. Detailed analyses were carried out on MPPT controllers in centralized and distributed architecture under partial shaded environments. The efficiency of the MPPT controllers and the effectiveness of the proposed control technique under partial shaded environments was examined using MATLAB software. The results were validated through experimentation.

  8. DC-bus voltage control of grid-connected voltage source converter by using space vector modulated direct power control under unbalanced network conditions

    DEFF Research Database (Denmark)

    Xiao, Lei; Huang, Shoudao; Lu, Kaiyuan

    2013-01-01

    Unbalanced grid voltage will cause large dc-bus voltage ripple and introduce high harmonic current components on the grid side. This will severely threaten the safety of the grid-connected voltage source converter (VSC) and consequently, affect the healthy operation condition of the load. In this......Unbalanced grid voltage will cause large dc-bus voltage ripple and introduce high harmonic current components on the grid side. This will severely threaten the safety of the grid-connected voltage source converter (VSC) and consequently, affect the healthy operation condition of the load....... In this study, a new proportional-integral-resonant (PI-RES) controller-based, space vector modulated direct power control topology is proposed to suppress the dc-bus voltage ripple and in the same time, controlling effectively the instantaneous power of the VSC. A special ac reactive power reference component...... is introduced in the controller, which is necessary in order to reduce the dc-bus voltage ripple and active power harmonics at the same time. The proposed control topology is implemented in the lab. Simulation and experimental results are provided to validate its performance and the analysis presented...

  9. An optimization strategy for the control of small capacity heat pump integrated air-conditioning system

    International Nuclear Information System (INIS)

    Gao, Jiajia; Huang, Gongsheng; Xu, Xinhua

    2016-01-01

    Highlights: • An optimization strategy for a small-scale air-conditioning system is developed. • The optimization strategy aims at optimizing the overall system energy consumption. • The strategy may guarantee the robust control of the space air temperature. • The performance of the optimization strategy was tested on a simulation platform. - Abstract: This paper studies the optimization of a small-scale central air-conditioning system, in which the cooling is provided by a ground source heat pump (GSHP) equipped with an on/off capacity control. The optimization strategy aims to optimize the overall system energy consumption and simultaneously guarantee the robustness of the space air temperature control without violating the allowed GSHP maximum start-ups number per hour specified by customers. The set-point of the chilled water return temperature and the width of the water temperature control band are used as the decision variables for the optimization. The performance of the proposed strategy was tested on a simulation platform. Results show that the optimization strategy can save the energy consumption by 9.59% in a typical spring day and 2.97% in a typical summer day. Meanwhile it is able to enhance the space air temperature control robustness when compared with a basic control strategy without optimization.

  10. Periodic spring–mass running over uneven terrain through feedforward control of landing conditions

    International Nuclear Information System (INIS)

    III, Luther R Palmer; Eaton, Caitrin E

    2014-01-01

    This work pursues a feedforward control algorithm for high-speed legged locomotion over uneven terrain. Being able to rapidly negotiate uneven terrain without visual or a priori information about the terrain will allow legged systems to be used in time-critical applications and alongside fast-moving humans or vehicles. The algorithm is shown here implemented on a spring-loaded inverted pendulum model in simulation, and can be configured to approach fixed running height over uneven terrain or self-stable terrain following. Offline search identifies unique landing conditions that achieve a desired apex height with a constant stride period over varying ground levels. Because the time between the apex and touchdown events is directly related to ground height, the landing conditions can be computed in real time as continuous functions of this falling time. Enforcing a constant stride period reduces the need for inertial sensing of the apex event, which is nontrivial for physical systems, and allows for clocked feedfoward control of the swing leg. (paper)

  11. Periodic spring-mass running over uneven terrain through feedforward control of landing conditions.

    Science.gov (United States)

    Palmer, Luther R; Eaton, Caitrin E

    2014-09-01

    This work pursues a feedforward control algorithm for high-speed legged locomotion over uneven terrain. Being able to rapidly negotiate uneven terrain without visual or a priori information about the terrain will allow legged systems to be used in time-critical applications and alongside fast-moving humans or vehicles. The algorithm is shown here implemented on a spring-loaded inverted pendulum model in simulation, and can be configured to approach fixed running height over uneven terrain or self-stable terrain following. Offline search identifies unique landing conditions that achieve a desired apex height with a constant stride period over varying ground levels. Because the time between the apex and touchdown events is directly related to ground height, the landing conditions can be computed in real time as continuous functions of this falling time. Enforcing a constant stride period reduces the need for inertial sensing of the apex event, which is nontrivial for physical systems, and allows for clocked feedfoward control of the swing leg.

  12. Hydrochemical transformations of river waters during the flow in the reception basin on the basis of Olechówka River in Łódź

    Directory of Open Access Journals (Sweden)

    Bagrowicz Tomasz

    2017-01-01

    Full Text Available This work presents the results of the research experiment of conducting hydrochemical observation of the Olechówka River in Łódź and its flow from the river source until its estuary. The main aim of the research was to set tendencies of changes in waters flowing down from municipal reception basin with developed rain drain system and in waters flowing into bathing areas at the same time. Along with the flow of the river, 12 measuring-research points were established. In each of those points, measurements of the discharge rate and mean flow velocity of water in the channel were performed, which enabled to set average time of the flow of water between individual measuring-research points. The time of storing water in reservoirs was taken into consideration. The total time of the flow of water in the Olechówka River amounted to 856 h and 15 min. The analyses included in situ measurements (T, pH, SEC, analytical determinations Cl−, NH4+, NO3−, TN, PO43−, TP and Oxidability. The interchangeability of values of tested indicators and discharge point out to their decrease along with the increase of water flowing in the riverbed. There were self-cleaning processes identified in the Olechówka River: dilution and denitrification, along with the accumulation of total phosphorus in the river flow.

  13. Nondestructive techniques for the control of conditioned radioactive wastes

    International Nuclear Information System (INIS)

    Delprato, U.

    1987-01-01

    The final product of the radwaste conditioning process must satisfy certain requirments and physico-chemical properties in order to assure its safe long-term behaviour. Of course, the foreseen quality assurance and quality control should be conducted by means of non-destructive techniques. This work presents an over-view of various applicable non-destructive methods of analysis, showing their fields of investigation in testing waste packages, together with some arising practical problems. The most promising methods, such as eddy current testing, ultrasonic testing, γ-scanning, γ-spectroscopy, neutron counting and computerized tomography, are treated more deeply and some applications are presented. Particular attention is devoted to the development of a device based on computerized tomography; its essential components are reported and some design problems are also discussed

  14. Energy Performance and Optimal Control of Air-conditioned Buildings Integrated with Phase Change Materials

    Science.gov (United States)

    Zhu, Na

    This thesis presents an overview of the previous research work on dynamic characteristics and energy performance of buildings due to the integration of PCMs. The research work on dynamic characteristics and energy performance of buildings using PCMs both with and without air-conditioning is reviewed. Since the particular interest in using PCMs for free cooling and peak load shifting, specific research efforts on both subjects are reviewed separately. A simplified physical dynamic model of building structures integrated with SSPCM (shaped-stabilized phase change material) is developed and validated in this study. The simplified physical model represents the wall by 3 resistances and 2 capacitances and the PCM layer by 4 resistances and 2 capacitances respectively while the key issue is the parameter identification of the model. This thesis also presents the studies on the thermodynamic characteristics of buildings enhanced by PCM and on the investigation of the impacts of PCM on the building cooling load and peak cooling demand at different climates and seasons as well as the optimal operation and control strategies to reduce the energy consumption and energy cost by reducing the air-conditioning energy consumption and peak load. An office building floor with typical variable air volume (VAV) air-conditioning system is used and simulated as the reference building in the comparison study. The envelopes of the studied building are further enhanced by integrating the PCM layers. The building system is tested in two selected cities of typical climates in China including Hong Kong and Beijing. The cold charge and discharge processes, the operation and control strategies of night ventilation and the air temperature set-point reset strategy for minimizing the energy consumption and electricity cost are studied. This thesis presents the simulation test platform, the test results on the cold storage and discharge processes, the air-conditioning energy consumption and demand

  15. Feedback linearization based control of a variable air volume air conditioning system for cooling applications.

    Science.gov (United States)

    Thosar, Archana; Patra, Amit; Bhattacharyya, Souvik

    2008-07-01

    Design of a nonlinear control system for a Variable Air Volume Air Conditioning (VAVAC) plant through feedback linearization is presented in this article. VAVAC systems attempt to reduce building energy consumption while maintaining the primary role of air conditioning. The temperature of the space is maintained at a constant level by establishing a balance between the cooling load generated in the space and the air supply delivered to meet the load. The dynamic model of a VAVAC plant is derived and formulated as a MIMO bilinear system. Feedback linearization is applied for decoupling and linearization of the nonlinear model. Simulation results for a laboratory scale plant are presented to demonstrate the potential of keeping comfort and maintaining energy optimal performance by this methodology. Results obtained with a conventional PI controller and a feedback linearizing controller are compared and the superiority of the proposed approach is clearly established.

  16. External access to ALICE controls conditions data

    International Nuclear Information System (INIS)

    Jadlovský, J; Jadlovská, A; Sarnovský, J; Jajčišin, Š; Čopík, M; Jadlovská, S; Papcun, P; Bielek, R; Čerkala, J; Kopčík, M; Chochula, P; Augustinus, A

    2014-01-01

    ALICE Controls data produced by commercial SCADA system WINCCOA is stored in ORACLE database on the private experiment network. The SCADA system allows for basic access and processing of the historical data. More advanced analysis requires tools like ROOT and needs therefore a separate access method to the archives. The present scenario expects that detector experts create simple WINCCOA scripts, which retrieves and stores data in a form usable for further studies. This relatively simple procedure generates a lot of administrative overhead – users have to request the data, experts needed to run the script, the results have to be exported outside of the experiment network. The new mechanism profits from database replica, which is running on the CERN campus network. Access to this database is not restricted and there is no risk of generating a heavy load affecting the operation of the experiment. The developed tools presented in this paper allow for access to this data. The users can use web-based tools to generate the requests, consisting of the data identifiers and period of time of interest. The administrators maintain full control over the data – an authorization and authentication mechanism helps to assign privileges to selected users and restrict access to certain groups of data. Advanced caching mechanism allows the user to profit from the presence of already processed data sets. This feature significantly reduces the time required for debugging as the retrieval of raw data can last tens of minutes. A highly configurable client allows for information retrieval bypassing the interactive interface. This method is for example used by ALICE Offline to extract operational conditions after a run is completed. Last but not least, the software can be easily adopted to any underlying database structure and is therefore not limited to WINCCOA.

  17. Variable structure TITO fuzzy-logic controller implementation for a solar air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Lygouras, J.N.; Pachidis, Th. [Laboratory of Electronics, School of Electrical and Computer Engineering, Democritus University of Thrace, GR-67100 Xanthi (Greece); Kodogiannis, V.S. [Centre for Systems Analysis, School of Computer Science, University of Westminster, London HA1 3TP (United Kingdom); Tarchanidis, K.N. [Department of Petroleum Technology, Technological Education Institute of Kavala, GR-65404, Kavala (Greece); Koukourlis, C.S. [Laboratory of Telecommunications, School of Electrical and Computer Engineering, Democritus University of Thrace, GR-67100 Xanthi (Greece)

    2008-04-15

    The design and implementation of a Two-Input/Two-Output (TITO) variable structure fuzzy-logic controller for a solar-powered air-conditioning system is described in this paper. Two DC motors are used to drive the generator pump and the feed pump of the solar air-conditioner. The first affects the temperature in the generator of the solar air-conditioner, while the second, the pressure in the power loop. The difficulty of Multi-Input/Multi-Output (MIMO) systems control is how to overcome the coupling effects among each degree of freedom. First, a traditional fuzzy-controller has been designed, its output being one of the components of the control signal for each DC motor driver. Secondly, according to the characteristics of the system's dynamics coupling, an appropriate coupling fuzzy-controller (CFC) is incorporated into a traditional fuzzy-controller (TFC) to compensate for the dynamic coupling among each degree of freedom. This control strategy simplifies the implementation problem of fuzzy control, but can also improve the control performance. This mixed fuzzy controller (MFC) can effectively improve the coupling effects of the systems, and this control strategy is easy to design and implement. Experimental results from the implemented system are presented. (author)

  18. Particle control in DIII-D with helium glow discharge conditioning

    International Nuclear Information System (INIS)

    Jackson, G.L.; Taylor, T.S.; Taylor, P.L.

    1990-01-01

    Helium glow discharge conditioning of DIII-D is routinely used before every tokamak discharge to desorb hydrogen from the graphite tiles, which are the plasma facing surfaces for the floor, inner wall and top of the vessel. In addition to reducing hydrogen fuelling of the plasma by the graphite surfaces, helium glow discharges are also effective in removing low-Z impurities, primarily in the form of carbon monoxide and hydrocarbons, and this has permitted higher current divertor operation and more rapid recovery from tokamak disruptions. Since the implementation of repetitive helium glow wall conditioning, the parameter space in which tokamak discharges in DIII-D can be obtained has been expanded to include the first observations of limiter H-mode confinement, the Ohmic H-mode with periods of up to 150 ms that are free of edge localized modes, more reliable low q operation with volume averaged beta of up to 9.3%, improved control over locked modes and plasma discharges at lower electron density. (author). 37 refs, 12 figs, 1 tab

  19. Balanced Current Control Strategy for Current Source Rectifier Stage of Indirect Matrix Converter under Unbalanced Grid Voltage Conditions

    Directory of Open Access Journals (Sweden)

    Yeongsu Bak

    2016-12-01

    Full Text Available This paper proposes a balanced current control strategy for the current source rectifier (CSR stage of an indirect matrix converter (IMC under unbalanced grid voltage conditions. If the three-phase grid connected to the voltage source inverter (VSI of the IMC has unbalanced voltage conditions, it affects the currents of the CSR stage and VSI stage, and the currents are distorted. Above all, the distorted currents of the CSR stage cause instability in the overall system, which can affect the life span of the system. Therefore, in this paper, a control strategy for balanced currents in the CSR stage is proposed. To achieve balanced currents in the CSR stage, the VSI stage should receive DC power without ripple components from the CSR stage. This is implemented by controlling the currents in the VSI stage. Therefore, the proposed control strategy decouples the positive and negative phase-sequence components existing in the unbalanced voltages and currents of the VSI stage. Using the proposed control strategy under unbalanced grid voltage conditions, the stability and life span of the overall system can be improved. The effectiveness of the proposed control strategy is verified by simulation and experimental results.

  20. Postural Stability of Patients with Schizophrenia during Challenging Sensory Conditions: Implication of Sensory Integration for Postural Control.

    Directory of Open Access Journals (Sweden)

    Ya-Ling Teng

    Full Text Available Postural dysfunctions are prevalent in patients with schizophrenia and affect their daily life and ability to work. In addition, sensory functions and sensory integration that are crucial for postural control are also compromised. This study intended to examine how patients with schizophrenia coordinate multiple sensory systems to maintain postural stability in dynamic sensory conditions. Twenty-nine patients with schizophrenia and 32 control subjects were recruited. Postural stability of the participants was examined in six sensory conditions of different level of congruency of multiple sensory information, which was based on combinations of correct, removed, or conflicting sensory inputs from visual, somatosensory, and vestibular systems. The excursion of the center of pressure was measured by posturography. Equilibrium scores were derived to indicate the range of anterior-posterior (AP postural sway, and sensory ratios were calculated to explore ability to use sensory information to maintain balance. The overall AP postural sway was significantly larger for patients with schizophrenia compared to the controls [patients (69.62±8.99; controls (76.53±7.47; t1,59 = -3.28, p<0.001]. The results of mixed-model ANOVAs showed a significant interaction between the group and sensory conditions [F5,295 = 5.55, p<0.001]. Further analysis indicated that AP postural sway was significantly larger for patients compared to the controls in conditions containing unreliable somatosensory information either with visual deprivation or with conflicting visual information. Sensory ratios were not significantly different between groups, although small and non-significant difference in inefficiency to utilize vestibular information was also noted. No significant correlations were found between postural stability and clinical characteristics. To sum up, patients with schizophrenia showed increased postural sway and a higher rate of falls during challenging sensory

  1. Design report on the guide box-reactivity and safety control plates for MPR reactor under normal operation conditions

    International Nuclear Information System (INIS)

    Markiewicz, M.

    1999-01-01

    The reactivity control system for the MPR reactor (Multi Purpose Reactor) is a critical component regarding safety, it must ensure a fast shut down, maintaining the reactor in subcritical condition under normal or accidental operation condition. For this purpose, this core component must be designed to maintain its operating capacity during all the residence time and under any foreseen operation condition. The mechanical design of control plates and guide boxes must comply with structural integrity, maintaining its geometric and dimensional stability within the pre-established limits to prevent interferences with other core components. For this, the heat generation effect, mechanical loads and environment and irradiation effects were evaluated during the mechanical design. The reactivity control system is composed of guide boxes, manufactured from Aluminium alloy, located between the fuel elements, and control absorber plates of Ag-In-Cd alloy hermetically enclosed by a cladding of stainless steel sliding inside de guide boxes. The upward-downward movement is transmitted by a rod from the motion device located at the reactor lower part. The design requirements, criteria and limits were established to fulfill with the normal and abnormal operation conditions. The design verifications were performed by analytical method, estimating the guide box and control plates residence time. The result of the analysis performed, shows that the design of the reactivity control system and the material selected, are appropriate to fulfill the functional requirements, with no failures attributed to the mechanical design. (author)

  2. Hydrochemical laboratory methods for Nagra's investigation programme

    International Nuclear Information System (INIS)

    Kussmaul, H.; Antonsen, O.

    1985-01-01

    Nagra's geological research program is directed toward determination of the possibilities for depositing high level radioactive waste at depth in Northern Switzerland. The program includes ground water analyses for chemical and biological constituents (analyses by Institut Fresenius) as well as for dissolved gases, uranium, and natural radioactivity (analyses by EIR, Eidgenoessisches Institut fuer Reaktorforschung). Two sources were utilized to obtain formation water chemistry in the study area. A regional program was established to investigate mineral and thermal waters. 17 sites of the regional program are scheduled for long term monitoring of water chemistry. A deep drilling program (12 locations projected) was initiated to obtain and analyze water samples from defined depths and formations under in situ conditions. Chapter 2 presents the analytical programs in detail. General chemistry was determined in all samples. In the regional program, well equipped wells and springs provided representative samples at most locations (cf chapter 3). However, at other locations impairment of sample quality could not be avoided. Given sufficient water flow, samples for the deep drilling program were taken both at the earth's surface under atmospheric pressure conditions (from artesian outflow or after pumping), and under formation pressure at various depths with specialized sample containers (chapter 3.7.3). Chapter 4 gives a listing of all analytical methods used in the study, their accuracy ranges and detection limits. Finally, this paper also presents some special problems encountered during the deep drilling program (cf chapter 5). Preliminary results show that no single method can provide completely satisfactory results for all deep drilling water sampling. A combination of procedures and critical evaluation of their respective data can, however, provide valuable information on the chemistry of waters from certain formations. (author)

  3. Hydro-chemical study of the evolution of interstellar pre-biotic molecules during the collapse of molecular clouds

    International Nuclear Information System (INIS)

    Majumdar, Liton; Das, Ankan; Chakrabarti, Sandip K.; Chakrabarti, Sonali

    2012-01-01

    One of the stumbling blocks for studying the evolution of interstellar molecules is the lack of adequate knowledge about the rate coefficients of various reactions which take place in the interstellar medium and molecular clouds. Some theoretical models of rate coefficients do exist in the literature for computing abundances of complex pre-biotic molecules. So far these have been used to study the abundances of these molecules in space. However, in order to obtain more accurate final compositions in these media, we have calculated the rate coefficients for the formation of some of the most important interstellar pre-biotic molecules by using quantum chemical theory. We use these rates inside our hydro-chemical model to examine the chemical evolution and final abundances of pre-biotic species during the collapsing phase of a proto-star. We find that a significant amount of various pre-biotic molecules could be produced during the collapse phase of a proto-star. We thoroughly study the formation of these molecules via successive neutral-neutral and radical-radical/radical-molecular reactions. We present the time evolution of the chemical species with an emphasis on how the production of these molecules varies with the depth of a cloud. We compare the formation of adenine in interstellar space using our rate-coefficients and using those obtained from existing theoretical models. Formation routes of the pre-biotic molecules are found to be highly dependent on the abundances of the reactive species and the rate coefficients involved in the reactions. The presence of grains strongly affects the abundances of the gas phase species. We also carry out a comparative study between different pathways available for the synthesis of adenine, alanine, glycine and other molecules considered in our network. Despite the huge abundances of the neutral reactive species, production of adenine is found to be strongly dominated by the radical-radical/radical-molecular reaction pathways

  4. 50 CFR 22.32 - Conditions and limitations on taking under depredation control order.

    Science.gov (United States)

    2010-10-01

    ... Golden Eagles § 22.32 Conditions and limitations on taking under depredation control order. (a) Whenever the taking of golden eagles without a permit is authorized for the seasonal protection of livestock, such birds may be taken by firearms, traps, or other suitable means except by poison or from aircraft...

  5. Differentiated spring behavior under changing hydrological conditions in an alpine karst aquifer

    Science.gov (United States)

    Filippini, Maria; Squarzoni, Gabriela; De Waele, Jo; Fiorucci, Adriano; Vigna, Bartolomeo; Grillo, Barbara; Riva, Alberto; Rossetti, Stefano; Zini, Luca; Casagrande, Giacomo; Stumpp, Christine; Gargini, Alessandro

    2018-01-01

    Limestone massifs with a high density of dolines form important karst aquifers in most of the Alps, often with groundwater circulating through deep karst conduits and water coming out of closely spaced springs with flow rates of over some cubic meters per second. Although several hydrogeological studies and tracing experiments were carried out in many of these carbonate mountains in the past, the hydrogeology of most of these karst aquifers is still poorly known. Geological, hydrodynamic and hydrochemical investigations have been carried out in one of the most representative of these areas (Cansiglio-Monte Cavallo, NE Italy) since spring 2015, in order to enhance the knowledge on this important type of aquifer system. Additionally, a cave-to-spring multitracer test was carried out in late spring 2016 by using three different fluorescent tracers. This hydrogeological study allowed: 1) gathering new detailed information on the geological and tectonic structure of such alpine karst plateau; 2) defining discharge rates of the three main springs (Gorgazzo, Santissima, and Molinetto) by constructing rating curves; 3) understanding the discharging behavior of the system with respect to different recharge conditions; 4) better defining the recharge areas of the three springs. The three nearby springs (the spring front stretches over 5 km), that drain the investigated karst aquifer system, show different behaviors with respect to changing discharge conditions, demonstrating this aquifer to be divided in partially independent drainage systems under low-flow conditions, when their chemistry is clearly differentiated. Under high-flow conditions, waters discharging at all springs show more similar geochemical characteristics. The combination of geochemistry, hydrodynamic monitoring and dye tracing tests has shown that the three springs have different recharge areas. The study points out that even closely spaced karst springs, that apparently drain the same karst mountain, can

  6. Diesel soot oxidation under controlled conditions

    OpenAIRE

    Song, Haiwen

    2003-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University, 11/12/2003. In order to improve understanding of diesel soot oxidation, an experimental rig was designed and set up, in which the soot oxidation conditions, such as temperature, oxygen partial pressure, and CO2 partial pressure, could be varied independently of each other. The oxidizing gas flow in the oxidizer was under laminar condition. This test rig comprised a naturally-aspirated single ...

  7. Frequency-Domain Robust Performance Condition for Controller Uncertainty in SISO LTI Systems: A Geometric Approach

    Directory of Open Access Journals (Sweden)

    Vahid Raissi Dehkordi

    2009-01-01

    Full Text Available This paper deals with the robust performance problem of a linear time-invariant control system in the presence of robust controller uncertainty. Assuming that plant uncertainty is modeled as an additive perturbation, a geometrical approach is followed in order to find a necessary and sufficient condition for robust performance in the form of a bound on the magnitude of controller uncertainty. This frequency domain bound is derived by converting the problem into an optimization problem, whose solution is shown to be more time-efficient than a conventional structured singular value calculation. The bound on controller uncertainty can be used in controller order reduction and implementation problems.

  8. Simple Moving Voltage Average Incremental Conductance MPPT Technique with Direct Control Method under Nonuniform Solar Irradiance Conditions

    Directory of Open Access Journals (Sweden)

    Amjad Ali

    2015-01-01

    Full Text Available A new simple moving voltage average (SMVA technique with fixed step direct control incremental conductance method is introduced to reduce solar photovoltaic voltage (VPV oscillation under nonuniform solar irradiation conditions. To evaluate and validate the performance of the proposed SMVA method in comparison with the conventional fixed step direct control incremental conductance method under extreme conditions, different scenarios were simulated. Simulation results show that in most cases SMVA gives better results with more stability as compared to traditional fixed step direct control INC with faster tracking system along with reduction in sustained oscillations and possesses fast steady state response and robustness. The steady state oscillations are almost eliminated because of extremely small dP/dV around maximum power (MP, which verify that the proposed method is suitable for standalone PV system under extreme weather conditions not only in terms of bus voltage stability but also in overall system efficiency.

  9. A Deep Quench Approach to the Optimal Control of an Allen–Cahn Equation with Dynamic Boundary Conditions and Double Obstacles

    International Nuclear Information System (INIS)

    Colli, Pierluigi; Farshbaf-Shaker, M. Hassan; Sprekels, Jürgen

    2015-01-01

    In this paper, we investigate optimal control problems for Allen-Cahn variational inequalities with a dynamic boundary condition involving double obstacle potentials and the Laplace-Beltrami operator. The approach covers both the cases of distributed controls and of boundary controls. The cost functional is of standard tracking type, and box constraints for the controls are prescribed. We prove existence of optimal controls and derive first-order necessary conditions of optimality. The general strategy is the following: we use the results that were recently established by two of the authors for the case of (differentiable) logarithmic potentials and perform a so-called “deep quench limit”. Using compactness and monotonicity arguments, it is shown that this strategy leads to the desired first-order necessary optimality conditions for the case of (non-differentiable) double obstacle potentials

  10. Regional differences in infection control conditions in a sample of primary health care services in Brazil

    Directory of Open Access Journals (Sweden)

    Mauro Henrique Nogueira Guimarães de Abreu

    2017-11-01

    Full Text Available International guidelines have pointed out the importance of the physical environment of health care facilities in preventing and controlling infection. We aimed to describe the physical environment of dental care facilities in Brazil in 2014, focusing on characteristics designed to control infections. Exactly 16,202 dental offices in the Brazilian Unified National Health System (SUS participated in this survey. Trained researchers extracted information about the infection control characteristics of health facilities by using a structured instrument. We used data from 12 dichotomous questions that evaluated the wall, floor, sink and tap conditions, and the presence and condition of sterilization equipment. We calculated a score by summing the number of characteristics handled appropriately for infection control, which could range from 0 to 12. Hierarchical cluster analyses were developed. None of the 12 criteria were met by all the oral health teams. Only 208 (1.3% dental offices correctly performed all 12-infection control practices. Two clusters, with different frequencies of structure for infection control in dental offices, were identified. South and Southeast regions had the highest frequencies for Cluster 1, with better structure of infection control in dental offices. Dental care facilities of oral health teams were not typically meeting the infection control guidelines regarding clinic design and equipment. Adherence to the guidelines varied among the Brazilian geographic regions.

  11. Assessment of Augmented Electronic Fuel Controls for Modular Engine Diagnostics and Condition Monitoring

    Science.gov (United States)

    1978-12-01

    removal of the horoscope . Diagnostic Conoctor - E4 Th10 E4 23-pin connoctor on the electrical control unit Is provided for ground- checking electrical...confidenou in engine condition monitoring * 1min general. Thi9 has boon especially true in~ eases where fUse signal s have c~aused engine shutdowns. Where ECWI

  12. Causal Factors and Adverse Conditions of Aviation Accidents and Incidents Related to Integrated Resilient Aircraft Control

    Science.gov (United States)

    Reveley, Mary S.; Briggs, Jeffrey L.; Evans, Joni K.; Sandifer, Carl E.; Jones, Sharon Monica

    2010-01-01

    The causal factors of accidents from the National Transportation Safety Board (NTSB) database and incidents from the Federal Aviation Administration (FAA) database associated with loss of control (LOC) were examined for four types of operations (i.e., Federal Aviation Regulation Part 121, Part 135 Scheduled, Part 135 Nonscheduled, and Part 91) for the years 1988 to 2004. In-flight LOC is a serious aviation problem. Well over half of the LOC accidents included at least one fatality (80 percent in Part 121), and roughly half of all aviation fatalities in the studied time period occurred in conjunction with LOC. An adverse events table was updated to provide focus to the technology validation strategy of the Integrated Resilient Aircraft Control (IRAC) Project. The table contains three types of adverse conditions: failure, damage, and upset. Thirteen different adverse condition subtypes were gleaned from the Aviation Safety Reporting System (ASRS), the FAA Accident and Incident database, and the NTSB database. The severity and frequency of the damage conditions, initial test conditions, and milestones references are also provided.

  13. Conceptual and numerical models of groundwater flow and solute transport in fracture zones: Application to the Aspo Island (Sweden); Modelos conceptuales y numericos de flujo y transporte de solutos en zonas de fractura: aplicacion a la isla de Aspo (Suecia)

    Energy Technology Data Exchange (ETDEWEB)

    Molinero, J.; Samper, J.

    2003-07-01

    Several countries around the world are considering the final disposal of high-level radioactive waste in deep repositories located in fractured granite formations. Evaluating the long term safety of such repositories requires sound conceptual and numerical models which must consider simultaneously groundwater flow, solute transport and chemical and radiological processes. These models are being developed from data and knowledge gained from in situ experiments carried out at deep underground laboratories such as that of Aspo, Sweden, constructed in fractured granite. The Redox Zone Experiment is one of such experiments performed at Aspo in order to evaluate the effects of the construction of the access tunnel on the hydrogeological and hydrochemical conditions of a fracture zone intersected by the tunnel. Previous authors interpreted hydrochemical and isotopic data of this experiment using a mass-balance approach based on a qualitative description of groundwater flow conditions. Such an interpretation, however, is subject to uncertainties related to an over-simplified conceptualization of groundwater flow. Here we present numerical models of groundwater flow and solute transport for this fracture zone. The first model is based on previously published conceptual model. It presents noticeable un consistencies and fails to match simultaneously observed draw downs and chloride breakthrough curves. To overcome its limitations, a revised flow and transport model is presented which relies directly on available hydrodynamic and transport parameters, is based on the identification of appropriate flow and transport boundary conditions and uses, when needed, solute data extrapolated from nearby fracture zones. A significant quantitative improvement is achieved with the revised model because its results match simultaneously drawdown and chloride data. Other improvements are qualitative and include: ensuring consistency of hydrodynamic and hydrochemical data and avoiding

  14. Conceptual and numerical models of groundwater flow and solute transport in fracture zones: Application to the Aspo Island (Sweden)

    International Nuclear Information System (INIS)

    Molinero, J.; Samper, J.

    2003-01-01

    Several countries around the world are considering the final disposal of high-level radioactive waste in deep repositories located in fractured granite formations. Evaluating the long term safety of such repositories requires sound conceptual and numerical models which must consider simultaneously groundwater flow, solute transport and chemical and radiological processes. These models are being developed from data and knowledge gained from in situ experiments carried out at deep underground laboratories such as that of Aspo, Sweden, constructed in fractured granite. The Redox Zone Experiment is one of such experiments performed at Aspo in order to evaluate the effects of the construction of the access tunnel on the hydrogeological and hydrochemical conditions of a fracture zone intersected by the tunnel. Previous authors interpreted hydrochemical and isotopic data of this experiment using a mass-balance approach based on a qualitative description of groundwater flow conditions. Such an interpretation, however, is subject to uncertainties related to an over-simplified conceptualization of groundwater flow. Here we present numerical models of groundwater flow and solute transport for this fracture zone. The first model is based on previously published conceptual model. It presents noticeable un consistencies and fails to match simultaneously observed draw downs and chloride breakthrough curves. To overcome its limitations, a revised flow and transport model is presented which relies directly on available hydrodynamic and transport parameters, is based on the identification of appropriate flow and transport boundary conditions and uses, when needed, solute data extrapolated from nearby fracture zones. A significant quantitative improvement is achieved with the revised model because its results match simultaneously drawdown and chloride data. Other improvements are qualitative and include: ensuring consistency of hydrodynamic and hydrochemical data and avoiding

  15. Control Efficacy of Fungicides on Chinese Cabbage Clubroot under Several Conditions

    Directory of Open Access Journals (Sweden)

    Min-Yong Eom

    2011-08-01

    Full Text Available To develop the efficient screening methods for antifungal compound active to Chinese cabbage clubroot caused by Plasmodiophora brassicae, the control efficacy of three fungicides fluazinam, ethaboxam, and cyazofamid on the disease was tested under several conditions such as soil types, cultivars of Chinese cabbage, growth stages of the host, and inoculum concentrations. The in vivo antifungal activities of the fungicides on clubroot of two Chinese cabbage cultivars were hardly different. At 7- and 14-day-old seedlings, the fungicides were more effective to control of clubroot than at 21-day-old seedlings. In a commercial horticulture media soil (CNS, disease severity of untreated controls was higher and control activity of the fungicides was less than in a mixture of CNS and upland soil (1:1, v/v. Disease development of the seedlings inoculated with P. brassicae at 1.8×10(7 spores/pot to 1.1×10(9 spores/pot was almost same, but control efficacy of the fungicides was negatively correlated with inoculum dosages. To effectively select in vivo antifungal compound on Chinese cabbage clubroot, 14-day-old seedlings need to be inoculated with P. brassicae by drenching the spore suspension to give 1×10(8 spores/pot 1 day after chemical treatment. To develop clubroot, the inoculated plants are incubated in a growth chamber at 20℃ for 2 days, and then cultivated in a greenhouse (20±5℃ for four weeks.

  16. Thermoelectric properties control due to doping level and sintering conditions for FGM thermoelectric element

    CERN Document Server

    Kajikawa, T; Shiraishi, K; Ohmori, M; Hirai, T

    1999-01-01

    Thermoelectric performance is determined with three factors, namely, Seebeck coefficient, electrical resistivity and thermal conductivity. For metal and single crystalline semiconductor, those factors have close interrelation each $9 other. However, as the sintered thermoelectric element has various levels of superstructure from macro scale and micro scale in terms of the thermoelectric mechanism, the relationship among them is more complex than that for the $9 melt- grown element, so it is suggested that the control of the temperature dependence of thermoelectric properties is possible to enhance the thermoelectric performance for wide temperature range due to FGM approach. The research $9 objective is to investigate the characteristics of the thermoelectric properties for various doping levels and hot-pressed conditions to make the thermoelectric elements for which the temperature dependence of the performance is $9 controlled due to FGM approach varying the doping levels and sintering conditions. By usage ...

  17. Conditioned food aversion to control outbreaks of intoxication by Ipomoea carnea and Turbina cordata in goats

    Science.gov (United States)

    Conditioned food aversion is used to train livestock to avoid the ingestion of toxic plants. This technique was used to control Turbina cordata poisoning in goats in one farm, and to control Ipomoea carnea subsp. istulosa poisoning in another farm. The goats were penned at night and the next mornin...

  18. Controlling the anodizing conditions in preparation of an nanoporous anodic aluminium oxide template

    Science.gov (United States)

    Nazemi, Azadeh; Abolfazl, Seyed; Sadjadi, Seyed

    2014-12-01

    Porous anodic aluminium oxide (AAO) template is commonly used in the synthesis of one-dimensional nanostructures, such as nanowires and nanorods, due to its simple fabrication process. Controlling the anodizing conditions is important because of their direct influence on the size of AAO template pores; it affects the size of nanostructures that are fabricated in AAO template. In present study, several alumina templates were fabricated by a two-step electrochemical anodization in different conditions, such as the time of first process, its voltage, and electrolyte concentration. The effect of these factors on pore diameters of AAO templates was investigated using scanning electron microscopy (SEM).

  19. The combined use of 87Sr/86Sr and carbon and water isotopes to study the hydrochemical interaction between groundwater and lakewater in mantled karst

    Science.gov (United States)

    Katz, Brian G.; Bullen, Thomas D.

    1996-12-01

    The hydrochemical interaction between groundwater and lakewater influences the composition of water that percolates downward from the surficial aquifer system through the underlying intermediate confining unit and recharges the Upper Floridan aquifer along highlands in Florida. The 87Sr/86Sr ratio along with the stable isotopes, D, 18O, and 13C were used as tracers to study the interaction between groundwater, lakewater, and aquifer minerals near Lake Barco, a seepage lake in the mantled karst terrane of northern Florida. Upgradient from the lake, the 87Sr/86Sr ratio of groundwater decreases with depth (mean values of 0.71004, 0.70890, and 0.70852 for water from the surficial aquifer system, intermediate confining unit, and Upper Floridan aquifer, respectively), resulting from the interaction of dilute oxygenated recharge water with aquifer minerals that are less radiogenic with depth. The concentrations of Sr2+ generally increase with depth, and higher concentrations of Sr2+ in water from the Upper Floridan aquifer (20-35 μg/L), relative to water from the surficial aquifer system and the intermediate confining unit, result from the dissolution of Sr-bearing calcite and dolomite in the Eocene limestone. Dissolution of calcite [δ13C= -1.6permil(‰)] is also indicated by an enriched δ13CDIC(-8.8 to -11.4 ‰) in water from the Upper Floridan aquifer, relative to the overlying hydrogeologic units (δ13CDICaquifer material become less radiogenic and the Sr2+ concentrations generally increase with depth. However, Sr2+ concentrations are substantially less than in upgradient groundwaters at similar depths. The lower Sr2+ concentrations result from the influence of anoxic lakewater leakage on the mobility of Sr2+ from clays. Based on results from mass-balance modeling, it is probable that cation exchange plays the dominant role in controlling the 87Sr/86Sr ratio of groundwater, both upgradient and downgradient from Lake Barco. Even though groundwater from the three

  20. Hydrologic conditions controlling runoff generation immediately after wildfire

    Science.gov (United States)

    Ebel, Brian A.; Moody, John A.; Martin, Deborah A.

    2012-01-01

    We investigated the control of postwildfire runoff by physical and hydraulic properties of soil, hydrologic states, and an ash layer immediately following wildfire. The field site is within the area burned by the 2010 Fourmile Canyon Fire in Colorado, USA. Physical and hydraulic property characterization included ash thickness, particle size distribution, hydraulic conductivity, and soil water retention curves. Soil water content and matric potential were measured indirectly at several depths below the soil surface to document hydrologic states underneath the ash layer in the unsaturated zone, whereas precipitation and surface runoff were measured directly. Measurements of soil water content showed that almost no water infiltrated below the ash layer into the near-surface soil in the burned site at the storm time scale (i.e., minutes to hours). Runoff generation processes were controlled by and highly sensitive to ash thickness and ash hydraulic properties. The ash layer stored from 97% to 99% of rainfall, which was critical for reducing runoff amounts. The hydrologic response to two rain storms with different rainfall amounts, rainfall intensity, and durations, only ten days apart, indicated that runoff generation was predominantly by the saturation-excess mechanism perched at the ash-soil interface during the first storm and predominantly by the infiltration-excess mechanism at the ash surface during the second storm. Contributing area was not static for the two storms and was 4% (saturation excess) to 68% (infiltration excess) of the catchment area. Our results showed the importance of including hydrologic conditions and hydraulic properties of the ash layer in postwildfire runoff generation models.

  1. Bidirectional control of a one-dimensional robotic actuator by operant conditioning of a single unit in rat motor cortex

    Directory of Open Access Journals (Sweden)

    Pierre-Jean eArduin

    2014-07-01

    Full Text Available The design of efficient neuroprosthetic devices has become a major challenge for the long-term goal of restoring autonomy to motor-impaired patients. One approach for brain control of actuators consists in decoding the activity pattern obtained by simultaneously recording large neuronal ensembles in order to predict in real-time the subject’s intention, and move the prosthesis accordingly. An alternative way is to assign the output of one or a few neurons by operant conditioning to control the prosthesis with rules defined by the experimenter, and rely on the functional adaptation of these neurons during learning to reach the desired behavioral outcome. Here, several motor cortex neurons were recorded simultaneously in head-fixed awake rats and were conditioned, one at a time, to modulate their firing rate up and down in order to control the speed and direction of a one-dimensional actuator carrying a water bottle. The goal was to maintain the bottle in front of the rat’s mouth, allowing it to drink. After learning, all conditioned neurons modulated their firing rate, effectively controlling the bottle position so that the drinking time was increased relative to chance. The mean firing rate averaged over all bottle trajectories depended non-linearly on position, so that the mouth position operated as an attractor. Some modifications of mean firing rate were observed in the surrounding neurons, but to a lesser extent. Notably, the conditioned neuron reacted faster and led to a better control than surrounding neurons, as calculated by using the activity of those neurons to generate simulated bottle trajectories. Our study demonstrates the feasibility, even in the rodent, of using a motor cortex neuron to control a prosthesis in real-time bidirectionally. The learning process includes modifications of the activity of neighboring cortical neurons, while the conditioned neuron selectively leads the activity patterns associated with the prosthesis

  2. Incorporating fan control into air-conditioning systems to improve energy efficiency and transient response

    International Nuclear Information System (INIS)

    Yeh, T.-J.; Chen, Yun-Jih; Hwang, Wei-Yang; Lin, Jin-Long

    2009-01-01

    Modern air-conditioners frequently incorporate variable-speed compressors and variable-opening expansion valves with feedback control to improve performance and power efficiency. Because making the fan speeds adjustable adds flexibility to the control design and thus can lead to further improvements in performance and efficiency, this paper proposes two control algorithms, respectively, incorporating the outdoor fan and the indoor fan as the additional control inputs for air-conditioning systems. Both of the control algorithms are designed based on a low-order, linear model obtained from system identification. The first algorithm, which modulates the outdoor fan speed, can reduce the steady state power consumption if the temperature difference between the condenser and the outdoor environment is controlled properly. The second algorithm, which adds one more degree of freedom to control by modulating the indoor fan speed, can improve the transient response because actuator saturations become less likely to occur. The two control algorithms are implemented on a split-type residential air-conditioner and their respective performance is validated experimentally.

  3. Increasing of prediction reliability of calcium carbonate scale formation in heat exchanger of secondary coolant circuits of thermal and nuclear power plants

    International Nuclear Information System (INIS)

    Tret'yakov, O.V.; Kritskij, V.G.; Styazhkin, P.S.

    1991-01-01

    Calcium carbonate scale formation in the secondary circuit heat exchanger of thermal and nuclear power plants is investigated. A model of calcium-carbonate scale formation providing quite reliable prediction of process running and the possibility of its control affecting the parameters of hydrochemical regime (HCR) is developed. The results can be used when designing the automatic-control system of HCR

  4. Experimental study on frosting control of mobile air conditioning system with microchannel evaporator

    International Nuclear Information System (INIS)

    Qu Xiaohua; Shi Junye; Qi Zhaogang; Chen Jiangping

    2011-01-01

    In this paper, a newly developed frost control system is proposed. System bench tests and vehicle test in wind tunnel have been carried out to explore the anti-frosting performance of automotive air conditioning system with microchannel evaporator. The experimental results are compared with the baseline conventional laminated evaporator system. The test results show that the installation position of temperature sensor can dramatically affect the anti-frosting performance. The clutch switching on/off temperature range of the microchannel evaporator is also experimentally studied. The test results show that, with a proper installation position and on/off temperature range, the system COP can be improved, and meanwhile the panel vents' air off temperature can be reduced, and temperature swing can be reduced. - Highlights: → The frost control systems were tested with microchannel and laminated evaporators separately. → The installation position of temperature sensor affects the anti-frosting performance. → Temperature control range affects the anti-frosting performance. → The panel vents' air off temperature and swing can be reduced by proper control parameters. → The system COP can be improved by proper control parameters.

  5. Study on the control of groundwater hazard at Gays river mine: Final report

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This report outlines a study to assess and investigate sources of groundwater inflow to Westminer Canada Ltd.'s Gays River lead-zinc mine in Nova Scotia. The study consisted of a hydrochemical assessment, a review of drainhole well screens and an underground pressure point measurement program, preparation of a , an airphoto interpretation study of sinkhole features, and a major piezometer installation and overburden soil investigation program. This report provides an overview of the program.

  6. Sporulation of Bremia lactucae affected by temperature, relative humidity, and wind in controlled conditions

    NARCIS (Netherlands)

    Su, H.; Bruggen, van A.H.C.; Subbarao, K.V.; Scherm, H.

    2004-01-01

    The effects of temperature (5 to 25degreesC), relative humidity (81 to 100%), wind speed (0 to 1.0 in s(-1)), and their interactions on sporulation of Bremia lactucae on lettuce cotyledons were investigated in controlled conditions. Sporulation was affected significantly (P <0.0001) by

  7. Improving safety margins for control room habitability, through heating/ventilation/air conditioning modifications

    International Nuclear Information System (INIS)

    Beach, D.R.; Fillingim, W.; Bell, G.; Eurich, R.G.

    1989-01-01

    The Fort Calhoun power station began operation in September 1973. Since that time, modifications to the plant have required the addition of a substantial number of electrical and control components in the control room, which has resulted in an increased heat load in this area. Additionally, NUREG-0737, Item III.D.3.4, imposed requirements on the ventilating system related to protection of personnel from the effects of toxic and radioactive gas releases, which were not considered in the original design. Omaha Public Power District (OPPD) has recently undertaken a major modification to the Fort Calhoun station control room ventilating system to improve the safety margins for control room habitability. The goals of the modification were to achieve adequate cooling capacity with fully redundant equipment, improve habitability under accident conditions, and eliminate several potential problems related to steam line break and equipment qualification. Additionally, the scope of the project grew as design problems emerged

  8. Biological control of white mold by Trichoderma harzianum in common bean under field conditions

    Directory of Open Access Journals (Sweden)

    Daniel Diego Costa Carvalho

    2015-12-01

    Full Text Available Abstract: The objective of this work was to evaluate Trichoderma harzianum isolates for biological control of white mold in common bean (Phaseolus vulgaris. Five isolates were evaluated for biocontrol of white mold in 'Perola' common bean under field conditions, in the 2009 and 2010 crop seasons. A commercial isolate (1306 and a control treatment were included. Foliar applications at 2x109 conidia mL-1 were performed at 42 and 52 days after sowing (DAS, in 2009, and at 52 DAS in 2010. The CEN287, CEN316, and 1306 isolates decreased the number of Sclerotinia sclerotiorum apothecia per square meter in comparison to the control, in both crop seasons. CEN287, CEN316, and 1306 decreased white mold severity during the experimental period, when compared to the control.

  9. Using a Novel Wireless-Networked Decentralized Control Scheme under Unpredictable Environmental Conditions.

    Science.gov (United States)

    Chang, Chung-Liang; Huang, Yi-Ming; Hong, Guo-Fong

    2015-11-12

    The direction of sunshine or the installation sites of environmental control facilities in the greenhouse result in different temperature and humidity levels in the various zones of the greenhouse, and thus, the production quality of crop is inconsistent. This study proposed a wireless-networked decentralized fuzzy control scheme to regulate the environmental parameters of various culture zones within a greenhouse. The proposed scheme can create different environmental conditions for cultivating different crops in various zones and achieve diversification or standardization of crop production. A star-type wireless sensor network is utilized to communicate with each sensing node, actuator node, and control node in various zones within the greenhouse. The fuzzy rule-based inference system is used to regulate the environmental parameters for temperature and humidity based on real-time data of plant growth response provided by a growth stage selector. The growth stage selector defines the control ranges of temperature and humidity of the various culture zones according to the leaf area of the plant, the number of leaves, and the cumulative amount of light. The experimental results show that the proposed scheme is stable and robust and provides basis for future greenhouse applications.

  10. Using a Novel Wireless-Networked Decentralized Control Scheme under Unpredictable Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Chung-Liang Chang

    2015-11-01

    Full Text Available The direction of sunshine or the installation sites of environmental control facilities in the greenhouse result in different temperature and humidity levels in the various zones of the greenhouse, and thus, the production quality of crop is inconsistent. This study proposed a wireless-networked decentralized fuzzy control scheme to regulate the environmental parameters of various culture zones within a greenhouse. The proposed scheme can create different environmental conditions for cultivating different crops in various zones and achieve diversification or standardization of crop production. A star-type wireless sensor network is utilized to communicate with each sensing node, actuator node, and control node in various zones within the greenhouse. The fuzzy rule-based inference system is used to regulate the environmental parameters for temperature and humidity based on real-time data of plant growth response provided by a growth stage selector. The growth stage selector defines the control ranges of temperature and humidity of the various culture zones according to the leaf area of the plant, the number of leaves, and the cumulative amount of light. The experimental results show that the proposed scheme is stable and robust and provides basis for future greenhouse applications.

  11. Power system security enhancement with unified power flow controller under multi-event contingency conditions

    Directory of Open Access Journals (Sweden)

    S. Ravindra

    2017-03-01

    Full Text Available Power system security analysis plays key role in enhancing the system security and to avoid the system collapse condition. In this paper, a novel severity function is formulated using transmission line loadings and bus voltage magnitude deviations. The proposed severity function and generation fuel cost objectives are analyzed under transmission line(s and/or generator(s contingency conditions. The system security under contingency conditions is analyzed using optimal power flow problem. An improved teaching learning based optimization (ITLBO algorithm has been presented. To enhance the system security under contingency conditions in the presence of unified power flow controller (UPFC, it is necessary to identify an optimal location to install this device. Voltage source based power injection model of UPFC, incorporation procedure and optimal location identification strategy based on line overload sensitivity indexes are proposed. The entire proposed methodology is tested on standard IEEE-30 bus test system with supporting numerical and graphical results.

  12. Frequency effect on p-nitrophenol degradation under conditions of strict acoustic and electric control

    Directory of Open Access Journals (Sweden)

    Chang-ping Zhu

    2011-03-01

    Full Text Available The process of decomposing p-nitrophenol (PNP with power ultrasound requires strict control of acoustic and electric conditions. In this study, the conditions, including acoustic power and acoustic intensity, but not ultrasonic frequency, were controlled strictly at constant levels. The absorbency and the COD concentrations of the samples were measured in order to show the variation of the sample concentration. The results show significant differences in the trend of the solution degradation rate as acoustic power increases after the PNP solution (with a concentration of 114 mg/L and a pH value of 5.4 is irradiated for 60 min with ultrasonic frequencies of 530.8 kHz, 610.6 kHz, 855.0 kHz, and 1 130.0 kHz. The degradation rate of the solution increases with time and acoustic power (acoustic intensity. On the other hand, the degradation rate of the solution is distinctly dependent on frequency when the acoustic power and intensity are strictly controlled and maintained at constant levels. The degradation rate of the PNP solution declines with ultrasonic frequencies of 530.8 kHz, 610.6 kHz, 855.0 kHz, and 1 130.0 kHz; the COD concentration, on the contrary, increase.

  13. Postural Stability of Patients with Schizophrenia during Challenging Sensory Conditions: Implication of Sensory Integration for Postural Control.

    Science.gov (United States)

    Teng, Ya-Ling; Chen, Chiung-Ling; Lou, Shu-Zon; Wang, Wei-Tsan; Wu, Jui-Yen; Ma, Hui-Ing; Chen, Vincent Chin-Hung

    2016-01-01

    Postural dysfunctions are prevalent in patients with schizophrenia and affect their daily life and ability to work. In addition, sensory functions and sensory integration that are crucial for postural control are also compromised. This study intended to examine how patients with schizophrenia coordinate multiple sensory systems to maintain postural stability in dynamic sensory conditions. Twenty-nine patients with schizophrenia and 32 control subjects were recruited. Postural stability of the participants was examined in six sensory conditions of different level of congruency of multiple sensory information, which was based on combinations of correct, removed, or conflicting sensory inputs from visual, somatosensory, and vestibular systems. The excursion of the center of pressure was measured by posturography. Equilibrium scores were derived to indicate the range of anterior-posterior (AP) postural sway, and sensory ratios were calculated to explore ability to use sensory information to maintain balance. The overall AP postural sway was significantly larger for patients with schizophrenia compared to the controls [patients (69.62±8.99); controls (76.53±7.47); t1,59 = -3.28, pmaintain balance compared to the controls.

  14. Sedimentary facies and lithologic characters as main factors controlling hydrocarbon accumulations and their critical conditions

    Directory of Open Access Journals (Sweden)

    Jun-Qing Chen

    2015-10-01

    Full Text Available Taking more than 1000 clastic hydrocarbon reservoirs of Bohai Bay Basin, Tarim Basin and Junggar Basin, China as examples, the paper has studied the main controlling factors of hydrocarbon reservoirs and their critical conditions to reveal the hydrocarbon distribution and to optimize the search for favorable targets. The results indicated that the various sedimentary facies and lithologic characters control the critical conditions of hydrocarbon accumulations, which shows that hydrocarbon is distributed mainly in sedimentary facies formed under conditions of a long-lived and relatively strong hydrodynamic environment; 95% of the hydrocarbon reservoirs and reserves in the three basins is distributed in siltstones, fine sandstones, lithified gravels and pebble-bearing sandstones; moreover, the probability of discovering conventional hydrocarbon reservoirs decreases with the grain size of the clastic rock. The main reason is that the low relative porosity and permeability of fine-grained reservoirs lead to small differences in capillary force compared with surrounding rocks small and insufficiency of dynamic force for hydrocarbon accumulation; the critical condition for hydrocarbon entering reservoir is that the interfacial potential in the surrounding rock (Φn must be more than twice of that in the reservoir (Φs; the probability of hydrocarbon reservoirs distribution decreases in cases where the hydrodynamic force is too high or too low and when the rocks have too coarse or too fine grains.

  15. Topographically-controlled site conditions drive vegetation pattern on inland dunes in Poland

    Science.gov (United States)

    Sewerniak, Piotr; Jankowski, Michał

    2017-07-01

    The inland dunes of Central Europe are commonly overplanted by Scots pine (Pinus sylvestris) monocultures in which the primary occurrence of the natural vegetation pattern is obliterated. We hypothesize that on naturally revegetated inland dunes the pattern is clear and driven by topographically-controlled site conditions. To test this hypothesis, we addressed the following research questions: (1) Does topography drive vegetation patterns on inland dunes and if so, what are main differences between vegetation in varying relief positions? (2) To what extent does topography involve the variability of microclimates and of soil properties, and how does the topographically-induced differentiation of these site conditions control vegetation patterns? We conducted interdisciplinary studies (applying floristic, pedological and microclimatic research techniques) on a naturally revegetated inland dune area situated on a military artillery training ground near Toruń, northern Poland. We investigated vegetation patterns with reference to three topographical position variants (north-facing slopes, south-facing slopes, and intra-dune depressions). We found distinct differences in vegetation characteristics covering the aforementioned topographical positions. This primarily concerned species composition of ground vegetation: Calluna vulgaris was dominant species on north-facing slopes, Corynephorus canescens on south-facing slopes, while Calamagrostis epigejos in intra-dune depressions. In comparison to dune slopes, the depressions were characterized by much higher biodiversity of vascular plant species. This followed the most favorable soil conditions for the existence of plants (higher moisture and nutrient pools) occurring in low topographical positions. However, tree succession was most advanced not in depressions, where the competitive impact of tall grasses on seedlings was recognized, but on north-facing slopes. Based on our results, we formulated some suggestions, which

  16. Energetic conditions promoting top-down control of prey by predators.

    Directory of Open Access Journals (Sweden)

    Kristin N Marshall

    Full Text Available Humans remove large amounts of biomass from natural ecosystems, and large bodied high trophic level animals are especially sensitive and vulnerable to exploitation. The effects of removing top-predators on food webs are often difficult to predict because of limited information on species interaction strengths. Here we used a three species predator-prey model to explore relationships between energetic properties of trophodynamic linkages and interaction strengths to provide heuristic rules that indicate observable energetic conditions that are most likely to lead to stable and strong top-down control of prey by predator species. We found that strong top-down interaction strengths resulted from low levels of energy flow from prey to predators. Strong interactions are more stable when they are a consequence of low per capita predation and when predators are subsidized by recruitment. Diet composition also affects stability, but the relationship depends on the form of the functional response. Our results imply that for generalist satiating predators, strong top-down control on prey is most likely for prey items that occupy a small portion of the diet and when density dependent recruitment is moderately high.

  17. PATs Operating in Water Networks under Unsteady Flow Conditions: Control Valve Manoeuvre and Overspeed Effect

    Directory of Open Access Journals (Sweden)

    Modesto Pérez-Sánchez

    2018-04-01

    Full Text Available The knowledge of transient conditions in water pressurized networks equipped with pump as turbines (PATs is of the utmost importance and necessary for the design and correct implementation of these new renewable solutions. This research characterizes the water hammer phenomenon in the design of PAT systems, emphasizing the transient events that can occur during a normal operation. This is based on project concerns towards a stable and efficient operation associated with the normal dynamic behaviour of flow control valve closure or by the induced overspeed effect. Basic concepts of mathematical modelling, characterization of control valve behaviour, damping effects in the wave propagation and runaway conditions of PATs are currently related to an inadequate design. The precise evaluation of basic operating rules depends upon the system and component type, as well as the required safety level during each operation.

  18. Performance of diagonal control structures at different operating conditions for polymer electrolyte membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Serra, Maria; Husar, Attila; Feroldi, Diego; Riera, Jordi [Institut de Robotica i Informatica Industrial, Universitat Politecnica de Catalunya, Consejo Superior de Investigaciones Cientificas, C. Llorens i Artigas 4, 08028 Barcelona (Spain)

    2006-08-25

    This work is focused on the selection of operating conditions in polymer electrolyte membrane fuel cells. It analyses efficiency and controllability aspects, which change from one operating point to another. Specifically, several operating points that deliver the same amount of net power are compared, and the comparison is done at different net power levels. The study is based on a complex non-linear model, which has been linearised at the selected operating points. Different linear analysis tools are applied to the linear models and results show important controllability differences between operating points. The performance of diagonal control structures with PI controllers at different operating points is also studied. A method for the tuning of the controllers is proposed and applied. The behaviour of the controlled system is simulated with the non-linear model. Conclusions indicate a possible trade-off between controllability and optimisation of hydrogen consumption. (author)

  19. Near-optimal order-reduced control for A/C (air-conditioning) system of EVs (electric vehicles)

    International Nuclear Information System (INIS)

    Chiu, Chien-Chin; Tsai, Nan-Chyuan; Lin, Chun-Chi

    2014-01-01

    This work is aimed to investigate the regulation problem for thermal comfortableness and propose control strategies for cabin environment of EVs (electric vehicles) by constructing a reduced-scale A/C (air-conditioning) system which mainly consists of two modules: ECB (environmental control box) and AHU (air-handling unit). Temperature and humidity in the ECB can be regulated by AHU via cooling, heating, mixing air streams and adjusting speed of fans. To synthesize the near-optimal controllers, the mathematical model for the system thermodynamics is developed by employing the equivalent lumped heat capacity approach, energy/mass conservation principle and the heat transfer theories. In addition, from the clustering pattern of system eigenvalues, the thermodynamics of the interested system can evidently be characterized by two-time-scale property. That is, the studied system can be decoupled into two subsystems, slow mode and fast mode, by singular perturbation technique. As to the optimal control strategies for EVs, by taking thermal comfortableness, humidity and energy consumption all into account, a series of optimal controllers is synthesized on the base of the order-reduced thermodynamic model. The feedback control loop for the experimental test rig is examined and realized by the aid of the control system development kit dSPACE DS1104 and the commercial software MATLAB/Simulink. To sum up, the intensive computer simulations and experimental results verify that the performance of the near-optimal order-reduced control law is almost as superior as that of standard LQR (Linear-Quadratic Regulator). - Highlights: • A reduced-scale test rig for A/C (air-conditioning) system to imitate the temperature/humidity of cabin in EV (electric vehicle) is constructed. • The non-linear thermodynamic model of A/C system can be decoupled by singular perturbation technique. • The temperature/humidity in cabin is regulated to the desired values by proposed optimal

  20. Temperature effect on rose downy mildew development under environmental controlled conditions

    Directory of Open Access Journals (Sweden)

    Juan José Filgueira D.

    2014-04-01

    Full Text Available The rose downy mildew disease, caused by Peronospora sparsa Berkeley, is one of the most important that affect rose crops in Colombia. To manage this disease, flower growers must deal with high-costs due to the excessive application of fungicides, but without good results. Studies on P. sparsa behavior have shown its narrow relationship with environmental conditions. In this study, the temperature effect was evaluated during the infection and sporulation of P. sparsa in Charlotte leaflets, a susceptible commercial variety, through an environmental controlled conditions system. Infection and sporulation were observed at different temperatures in a range of from 4 to 40°C. Infection with the absence of or very low sporulation was observed at 4°C. The most favorable pathogen responses were between 15 and 18°C in terms of inoculum concentration and sporulation percentage. There was no infection or leaflet change above 35°C. According to the results, sporulation can occur from 4 to 33°C, confirming the fact that P. sparsa is able to reproduce throughout a wide temperature range.

  1. Noble gas control room accident filtration system for severe accident conditions (N-CRAFT)

    International Nuclear Information System (INIS)

    Hill, Axel; Stiepani, Cristoph; Drechsler, Michael

    2015-01-01

    Severe accidents might cause the release of airborne radioactive substances to the environment of the NPP either due to containment leakages or due to intentional filtered containment venting. In the latter case aerosols and iodine are retained, however noble gases are not retainable by the FCVS or by conventional air filtration systems like HEPA filters and iodine absorbers. Radioactive noble gases nevertheless dominate the activity release depending on the venting procedure and the weather conditions. To prevent unacceptable contamination of the control room atmosphere by noble gases, AREVA GmbH has developed a noble gas control room accident filtration system (CRAFT) which can supply purified fresh air to the control room without time limitation. The retention process is based on dynamic adsorption of noble gases on activated carbon. The system consists of delay lines (carbon columns) which are operated by a continuous and simultaneous adsorption and desorption process. CRAFT allows minimization of the dose rate inside the control room and ensures low radiation exposure to the staff by maintaining the control room environment suitable for prolonged occupancy throughout the duration of the accident. CRAFT consists of a proven modular design either transportable or permanently installed. (author)

  2. Towards artificial intelligence based diesel engine performance control under varying operating conditions using support vector regression

    Directory of Open Access Journals (Sweden)

    Naradasu Kumar Ravi

    2013-01-01

    Full Text Available Diesel engine designers are constantly on the look-out for performance enhancement through efficient control of operating parameters. In this paper, the concept of an intelligent engine control system is proposed that seeks to ensure optimized performance under varying operating conditions. The concept is based on arriving at the optimum engine operating parameters to ensure the desired output in terms of efficiency. In addition, a Support Vector Machines based prediction model has been developed to predict the engine performance under varying operating conditions. Experiments were carried out at varying loads, compression ratios and amounts of exhaust gas recirculation using a variable compression ratio diesel engine for data acquisition. It was observed that the SVM model was able to predict the engine performance accurately.

  3. The role of meteorological conditions and pollution control strategies in reducing air pollution in Beijing during APEC 2014 and Victory Parade 2015

    Science.gov (United States)

    Liang, Pengfei; Zhu, Tong; Fang, Yanhua; Li, Yingruo; Han, Yiqun; Wu, Yusheng; Hu, Min; Wang, Junxia

    2017-11-01

    To control severe air pollution in China, comprehensive pollution control strategies have been implemented throughout the country in recent years. To evaluate the effectiveness of these strategies, the influence of meteorological conditions on levels of air pollution needs to be determined. Using the intensive air pollution control strategies implemented during the Asia-Pacific Economic Cooperation Forum in 2014 (APEC 2014) and the 2015 China Victory Day Parade (Victory Parade 2015) as examples, we estimated the role of meteorological conditions and pollution control strategies in reducing air pollution levels in Beijing. Atmospheric particulate matter of aerodynamic diameter ≤ 2.5 µm (PM2.5) samples were collected and gaseous pollutants (SO2, NO, NOx, and O3) were measured online at a site in Peking University (PKU). To determine the influence of meteorological conditions on the levels of air pollution, we first compared the air pollutant concentrations during days with stable meteorological conditions. However, there were few days with stable meteorological conditions during the Victory Parade. As such, we were unable to estimate the level of emission reduction efforts during this period. Finally, a generalized linear regression model (GLM) based only on meteorological parameters was built to predict air pollutant concentrations, which could explain more than 70 % of the variation in air pollutant concentration levels, after incorporating the nonlinear relationships between certain meteorological parameters and the concentrations of air pollutants. Evaluation of the GLM performance revealed that the GLM, even based only on meteorological parameters, could be satisfactory to estimate the contribution of meteorological conditions in reducing air pollution and, hence, the contribution of control strategies in reducing air pollution. Using the GLM, we found that the meteorological conditions and pollution control strategies contributed 30 and 28 % to the reduction

  4. Data support system for controlling decentralised nuclear power industry facilities through uninterruptible condition monitoring

    Directory of Open Access Journals (Sweden)

    Povarov Vladimir

    2018-01-01

    Full Text Available The article describes the automated uninterruptible multi-parameter system for monitoring operational vulnerability of critical NPP components, which differs from existing ones by being universally applicable for analysing mechanical damage of nuclear power unit components. The system allows for performing routine assessment of metal structures. The assessment of strained condition of a deteriorating component is based on three-dimensional finite element simulation with calculations adjusted with reference to in-situ measurements. A program for calculation and experimental analysis of maximum load and durability of critical area forms the core of uninterruptible monitoring system. The knowledge base on performance of the monitored components in different operating conditions and the corresponding comprehensive analysis of strained condition and deterioration rates compose the basis of control system data support, both for operating nuclear power units and robotic maintenance and repair systems.

  5. Radioactive contamination of Bunodosoma caissarum under controlled conditions

    International Nuclear Information System (INIS)

    Santos Gouvea, R. de C. dos; Santos, P.L. dos

    The kinetics of uptake and release of radionuclides 137 Cs, 131 I, 133 Ba, 51 Cr (III and VI), 60 Co and 65 Zn in the 'cnidaria' Bunodosoma caissarum have been studied. This is an exclusively Brazilian species and easily collected on the Rio de Janeiro coastal waters. The kinetic experiments have been made in aquariums of 1000 cm 3 , in laboratory under controlled conditions and accompanied by single channel radiometry. The velocities of concentration were evident to radionuclides 131 I and 133 Ba. The larger concentration factors were registred to 51 Cr (III), 65 Zn and 51 Cr (VI), with middle values of 20,0 , 14,5 and 8,6 respectively. The same radionuclides stood out in the loss experiments, presenting the following biological half-lives : 292,2 h ( 51 Cr-III), 784,0 h ( 51 Cr-VI) and 823,0 h ( 65 Zn). This expressive value for the 65 Zn suggests a probable biological integration of this radionuclide by the species studied. The results allow us to indicate the 'anthozoa' Bunodosoma caissarum as a bioindicator of the radioactive contamination of the marine environment. (Author) [pt

  6. Optimizing grade-control drillhole spacing with conditional simulations

    Directory of Open Access Journals (Sweden)

    Adrian Martínez-Vargas

    2017-01-01

    Full Text Available This paper summarizes a method to determine the optimum spacing of grade-control drillholes drilled with reverse-circulation. The optimum drillhole spacing was defined as that one whose cost equals the cost of misclassifying ore and waste in selection mining units (SMU. The cost of misclassification of a given drillhole spacing is equal to the cost of processing waste misclassified as ore (Type I error plus the value of the ore misclassified as waste (Type II error. Type I and Type II errors were deduced by comparing true and estimated grades at SMUs, in relation to a cuttoff grade value and assuming free ore selection. True grades at SMUs and grades at drillhole samples were generated with conditional simulations. A set of estimated grades at SMU, one per each drillhole spacing, were generated with ordinary kriging. This method was used to determine the optimum drillhole spacing in a gold deposit. The results showed that the cost of misclassification is sensitive to extreme block values and tend to be overrepresented. Capping SMU’s lost values and implementing diggability constraints was recommended to improve calculations of total misclassification costs.

  7. Hydrochemistry and Isotope Hydrology for Groundwater Sustainability of the Coastal Multilayered Aquifer System (Zhanjiang, China

    Directory of Open Access Journals (Sweden)

    Pengpeng Zhou

    2017-01-01

    Full Text Available Groundwater sustainability has become a critical issue for Zhanjiang (China because of serious groundwater level drawdown induced by overexploitation of its coastal multilayered aquifer system. It is necessary to understand the origins, material sources, hydrochemical processes, and dynamics of the coastal groundwater in Zhanjiang to support its sustainable management. To this end, an integrated analysis of hydrochemical and isotopic data of 95 groundwater samples was conducted. Hydrochemical analysis shows that coastal groundwater is fresh; however, relatively high levels of Cl−, Mg2+, and total dissolved solid (TDS imply slight seawater mixing with coastal unconfined groundwater. Stable isotopes (δ18O and δ2H values reveal the recharge sources of groundwater in the multilayered aquifer system. The unconfined groundwater originates from local modern precipitation; the confined groundwater in mainland originates from modern precipitation in northwestern mountain area, and the confined groundwater in Donghai and Leizhou is sourced from rainfall recharge during an older period with a colder climate. Ionic relations demonstrate that silicate weathering, carbonate dissolutions, and cation exchange are the primary processes controlling the groundwater chemical composition. Declining trends of groundwater level and increasing trends of TDS of the confined groundwater in islands reveal the landward extending tendency of the freshwater-seawater mixing zone.

  8. Towards the control of car underhood thermal conditions

    International Nuclear Information System (INIS)

    Khaled, Mahmoud; Harambat, Fabien; Peerhossaini, Hassan

    2011-01-01

    The present paper reports an experimental study of the aerothermal phenomena in the vehicle underhood compartment as investigated by measuring temperature, convective heat flux, and radiative heat flux. Measurements are carried out on a passenger vehicle in wind tunnel S4 of Saint-Cyr-France. The underhood space is instrumented by 120 surface and air thermocouples and 20 fluxmeters. Measurements are performed for three thermal functioning conditions while the engine is in operation and the front wheels are positioned on the test facility with power-absorption-controlled rollers. In the thermal analysis, particular attention is given to measuring absorbed convective heat fluxes at component surfaces. It is shown that, in some components, the outside air entering the engine compartment (for cooling certain components) can in fact heat other components. This problem arises from the underhood architecture, specifically the positioning of some components downstream of warmer components in the same airflow. Optimized thermal management suggests placing these components further upstream or isolating them from the hot stream by deflectors. Given style constraints, however, the use of air deflectors is more suitable than underhood architectural changes. Much of the present paper is devoted to heat flux analysis of the specific thermal behaviours in the underhood compartment (especially the absorption of convective heat fluxes) and to a description of a new control approach exploiting air deflectors to optimize underhood aerothermal management. - Research highlights: → We present a physical analysis of particular underhood aerothermal behaviors. → In this analysis, convective heat flux absorption should be noted. → A new optimization procedure based on this physical analysis is proposed. → It entails airflow redistribution in the underhood through deflectors. → The new procedures are simple and easy to implement in the car underhood.

  9. Muscarinic receptors in amygdala control trace fear conditioning.

    Directory of Open Access Journals (Sweden)

    Amber N Baysinger

    Full Text Available Intelligent behavior requires transient memory, which entails the ability to retain information over short time periods. A newly-emerging hypothesis posits that endogenous persistent firing (EPF is the neurophysiological foundation for aspects or types of transient memory. EPF is enabled by the activation of muscarinic acetylcholine receptors (mAChRs and is triggered by suprathreshold stimulation. EPF occurs in several brain regions, including the lateral amygdala (LA. The present study examined the role of amygdalar mAChRs in trace fear conditioning, a paradigm that requires transient memory. If mAChR-dependent EPF selectively supports transient memory, then blocking amygdalar mAChRs should impair trace conditioning, while sparing delay and context conditioning, which presumably do not rely upon transient memory. To test the EPF hypothesis, LA was bilaterally infused, prior to trace or delay conditioning, with either a mAChR antagonist (scopolamine or saline. Computerized video analysis quantified the amount of freezing elicited by the cue and by the training context. Scopolamine infusion profoundly reduced freezing in the trace conditioning group but had no significant effect on delay or context conditioning. This pattern of results was uniquely anticipated by the EPF hypothesis. The present findings are discussed in terms of a systems-level theory of how EPF in LA and several other brain regions might help support trace fear conditioning.

  10. Muscarinic receptors in amygdala control trace fear conditioning.

    Science.gov (United States)

    Baysinger, Amber N; Kent, Brianne A; Brown, Thomas H

    2012-01-01

    Intelligent behavior requires transient memory, which entails the ability to retain information over short time periods. A newly-emerging hypothesis posits that endogenous persistent firing (EPF) is the neurophysiological foundation for aspects or types of transient memory. EPF is enabled by the activation of muscarinic acetylcholine receptors (mAChRs) and is triggered by suprathreshold stimulation. EPF occurs in several brain regions, including the lateral amygdala (LA). The present study examined the role of amygdalar mAChRs in trace fear conditioning, a paradigm that requires transient memory. If mAChR-dependent EPF selectively supports transient memory, then blocking amygdalar mAChRs should impair trace conditioning, while sparing delay and context conditioning, which presumably do not rely upon transient memory. To test the EPF hypothesis, LA was bilaterally infused, prior to trace or delay conditioning, with either a mAChR antagonist (scopolamine) or saline. Computerized video analysis quantified the amount of freezing elicited by the cue and by the training context. Scopolamine infusion profoundly reduced freezing in the trace conditioning group but had no significant effect on delay or context conditioning. This pattern of results was uniquely anticipated by the EPF hypothesis. The present findings are discussed in terms of a systems-level theory of how EPF in LA and several other brain regions might help support trace fear conditioning.

  11. Birds achieve high robustness in uneven terrain through active control of landing conditions.

    Science.gov (United States)

    Birn-Jeffery, Aleksandra V; Daley, Monica A

    2012-06-15

    We understand little about how animals adjust locomotor behaviour to negotiate uneven terrain. The mechanical demands and constraints of such behaviours likely differ from uniform terrain locomotion. Here we investigated how common pheasants negotiate visible obstacles with heights from 10 to 50% of leg length. Our goal was to determine the neuro-mechanical strategies used to achieve robust stability, and address whether strategies vary with obstacle height. We found that control of landing conditions was crucial for minimising fluctuations in stance leg loading and work in uneven terrain. Variation in touchdown leg angle (θ(TD)) was correlated with the orientation of ground force during stance, and the angle between the leg and body velocity vector at touchdown (β(TD)) was correlated with net limb work. Pheasants actively targeted obstacles to control body velocity and leg posture at touchdown to achieve nearly steady dynamics on the obstacle step. In the approach step to an obstacle, the birds produced net positive limb work to launch themselves upward. On the obstacle, body dynamics were similar to uniform terrain. Pheasants also increased swing leg retraction velocity during obstacle negotiation, which we suggest is an active strategy to minimise fluctuations in peak force and leg posture in uneven terrain. Thus, pheasants appear to achieve robustly stable locomotion through a combination of path planning using visual feedback and active adjustment of leg swing dynamics to control landing conditions. We suggest that strategies for robust stability are context specific, depending on the quality of sensory feedback available, especially visual input.

  12. Development of novel control strategy for multiple circuit, roof top bus air conditioning system in hot humid countries

    Energy Technology Data Exchange (ETDEWEB)

    Khamis Mansour, M.; Musa, Md Nor; Wan Hassan, Mat Nawi; Saqr, Khalid M. [Thermo-Fluid Department, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru (Malaysia)

    2008-06-15

    A novel control strategy to improve energy efficiency and to enhance passengers' thermal comfort of a new roof top bus multiple circuit air conditioning (AC) system operating on partial load conditions is presented. A novel strategy for automatic control of the AC system was developed based on numerous experimental test runs at various operating conditions, taking into account energy saving and thermal comfort without sacrificing the proper cycling rate of the system compressor. For this task, more than 50 test runs were conducted at different set point temperatures of 21, 22 and 23 C. Fanger's method was used to evaluate passenger thermal comfort, and the system energy consumption was also calculated. A performance comparison between that of the conventional AC system and that of the newly developed one has been conducted. The comparison revealed that the adopted control strategy introduces significant improvements in terms of thermal comfort and energy saving on various partial load conditions. Potential energy saving of up to 31.6% could be achieved. This results in a short payback period of 17 months. It was found from the economic analysis that the new system is able to save approximately 20.0% of the life cycle cost. (author)

  13. Development of novel control strategy for multiple circuit, roof top bus air conditioning system in hot humid countries

    International Nuclear Information System (INIS)

    Khamis Mansour, M.; Musa, Md Nor; Mat Nawi Wan Hassan; Saqr, Khalid M.

    2008-01-01

    A novel control strategy to improve energy efficiency and to enhance passengers' thermal comfort of a new roof top bus multiple circuit air conditioning (AC) system operating on partial load conditions is presented. A novel strategy for automatic control of the AC system was developed based on numerous experimental test runs at various operating conditions, taking into account energy saving and thermal comfort without sacrificing the proper cycling rate of the system compressor. For this task, more than 50 test runs were conducted at different set point temperatures of 21, 22 and 23 deg. C. Fanger's method was used to evaluate passenger thermal comfort, and the system energy consumption was also calculated. A performance comparison between that of the conventional AC system and that of the newly developed one has been conducted. The comparison revealed that the adopted control strategy introduces significant improvements in terms of thermal comfort and energy saving on various partial load conditions. Potential energy saving of up to 31.6% could be achieved. This results in a short payback period of 17 months. It was found from the economic analysis that the new system is able to save approximately 20.0% of the life cycle cost

  14. CALCULATION AND ANALYSIS OF THE EXPECTED IMPACT OF THE HYDROTECHNICAL CONSTRUCTION ON THE ENVIRONMENTAL CONDITION IN THE WATER AREA AND BOTTOM TOPOGRAPHY IN CASE OF THE CONSTRUCTION OF THE APPROACH CHANNEL TO THE SABETTA PORT

    Directory of Open Access Journals (Sweden)

    Vvedensky Alexei Rostislavovich

    2017-05-01

    Full Text Available The estimation of changes in the ecological situation and bottom topography in the Ob Bay, which may be caused by the construction of the approach channel to the port of Sabetta, was carried out with the help of the developed complex of numerical models. Particular attention was paid to the study of the displacement of the boundaries of the saline water expansion and the sediment accumulation in the channel area. It is established that the possible influence of the approach channel on the hydrologic-hydrochemical characteristics is less than their natural interannual and seasonal variability in the investigated water area. The change in the bottom topography after the construction of the approach channel does not entail a significant change in the regime of hydrologic-hydrochemical parameters of the Ob Bay and, consequently, should not affect the biocenosis. The calculated changes in the bottom topography in the approach channel area will not exceed 2 % of the depth per year and will not become a significant obstacle to the reliable and uninterrupted operation of the Sabetta port.

  15. HYDROCHEMICAL CONDITIONS OF THE ŁOSOSINA RIVER WATER MANAGEMENT IN THE AREA OF TYMBARK

    OpenAIRE

    Agnieszka Policht-Latawiec; Włodzimierz Kanownik

    2015-01-01

    Sustainable use of waters requires not only determining the amount, but primarily the quality of the available water resources and developing a long-term programme of their protection. The analysis of the Łososina river water in the area of Tymbark city was presented in the paper. The water was tested in a view of the requirements as the natural fish habitat and its potential use for people supply in potable water. The river water samples were taken in 2014 at randomly selected dates, once a ...

  16. HYDROCHEMICAL CONDITIONS OF THE ŁOSOSINA RIVER WATER MANAGEMENT IN THE AREA OF TYMBARK

    Directory of Open Access Journals (Sweden)

    Agnieszka Policht-Latawiec

    2015-11-01

    Full Text Available Sustainable use of waters requires not only determining the amount, but primarily the quality of the available water resources and developing a long-term programme of their protection. The analysis of the Łososina river water in the area of Tymbark city was presented in the paper. The water was tested in a view of the requirements as the natural fish habitat and its potential use for people supply in potable water. The river water samples were taken in 2014 at randomly selected dates, once a month in 5 measurement points. 21 physicochemical indices were assessed in the samples. The assessment of the Łososina river water quality was made on the basis of the results of both: on site and laboratory testing, which were compared with the Regulation of the Minister of Environment of 23 October 2014. The utility values were assessed on the basis of the Regulations of the Minister of Environment of 27 November and 04 October 2014. The analysis of the results demonstrated that the Łososina river water met the requirements of quality class I water in points 1, 2 and 3. Below Tymbark the Łososina river water was polluted, so due to high BOD5 in points 4 and 5, and phosphate concentrations in point 4, it was classified as class II, i.e. good state. Pollution coefficients computed according to Burchard and Dubaniewicz classify the Łososina river water as clean along the whole investigated stretch. Below Tymbark city (points 4 and 5 the Łososina river water cannot be used for drinking water supply because of high BOD5 and iron concentrations. In the other points it could be used for water supply following appropriate physical and chemical treatment. The water does not meet the requirements for salmonid or cyprinid fish along the whole stretch because of high nitrite concentrations, except point 3, where the Łososina river water provided a proper natural habitat for carp.

  17. Are bioassays useful tools to assess redox processes and biodegradation?

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Pedersen, Philip Grinder; Ludvigsen, L.

    2002-01-01

    sensitive hydrochemical or geochemical parameters, levels of hydrogen, and redox potential. However, all these approaches have to be evaluated against TEAP-bioassays as the most direct measure. We assessed successfully ongoing microbial-mediated redox processes by TEAP-bioassays in degradation studies...... of aromatic and chlorinated aliphatic compounds in landfill leachate plumes, and of pesticides in aquifers with various redox conditions....

  18. DEVELOPMENT AND APPLICATION OF THE KEY TECHNOLOGIES FOR THE QUALITY CONTROL AND INSPECTION OF NATIONAL GEOGRAPHICAL CONDITIONS SURVEY PRODUCTS

    Directory of Open Access Journals (Sweden)

    Y. Zhao

    2018-04-01

    Full Text Available The First National Geographical Condition Survey is a predecessor task to dynamically master basic situations of the nature, ecology and human activities on the earth’s surface and it is the brand-new mapping geographic information engineering. In order to ensure comprehensive, real and accurate survey results and achieve the quality management target which the qualified rate is 100 % and the yield is more than 80 %, it is necessary to carry out the quality control and result inspection for national geographical conditions survey on a national scale. To ensure that achievement quality meets quality target requirements, this paper develops the key technology method of “five-in-one” quality control that is constituted by “quality control system of national geographical condition survey, quality inspection technology system, quality evaluation system, quality inspection information management system and national linked quality control institutions” by aiming at large scale, wide coverage range, more undertaking units, more management levels, technical updating, more production process and obvious regional differences in the national geographical condition survey and combining with novel achievement manifestation, complicated dependency, more special reference data, and large data size. This project fully considering the domestic and foreign related research results and production practice experience, combined with the technology development and the needs of the production, it stipulates the inspection methods and technical requirements of each stage in the quality inspection of the geographical condition survey results, and extends the traditional inspection and acceptance technology, and solves the key technologies that are badly needed in the first national geographic survey.

  19. Development and Application of the Key Technologies for the Quality Control and Inspection of National Geographical Conditions Survey Products

    Science.gov (United States)

    Zhao, Y.; Zhang, L.; Ma, W.; Zhang, P.; Zhao, T.

    2018-04-01

    The First National Geographical Condition Survey is a predecessor task to dynamically master basic situations of the nature, ecology and human activities on the earth's surface and it is the brand-new mapping geographic information engineering. In order to ensure comprehensive, real and accurate survey results and achieve the quality management target which the qualified rate is 100 % and the yield is more than 80 %, it is necessary to carry out the quality control and result inspection for national geographical conditions survey on a national scale. To ensure that achievement quality meets quality target requirements, this paper develops the key technology method of "five-in-one" quality control that is constituted by "quality control system of national geographical condition survey, quality inspection technology system, quality evaluation system, quality inspection information management system and national linked quality control institutions" by aiming at large scale, wide coverage range, more undertaking units, more management levels, technical updating, more production process and obvious regional differences in the national geographical condition survey and combining with novel achievement manifestation, complicated dependency, more special reference data, and large data size. This project fully considering the domestic and foreign related research results and production practice experience, combined with the technology development and the needs of the production, it stipulates the inspection methods and technical requirements of each stage in the quality inspection of the geographical condition survey results, and extends the traditional inspection and acceptance technology, and solves the key technologies that are badly needed in the first national geographic survey.

  20. Adaptive Fuzzy Logic based MPPT Control for PV System Under Partial Shading Condition

    OpenAIRE

    Choudhury, Subhashree; Rout, Pravat Kumar

    2016-01-01

    Partial shading causes power loss, hotspots and threatens the reliability of the Photovoltaic generation system. Moreover characteristic curves exhibit multiple peaks. Conventional MPPT techniques under this condition often fail to give optimum MPP. Focusing on the afore mentioned problem an attempt has been made to design an Adaptive Takagi-Sugeno Fuzzy Inference System based Fuzzy Logic Control MPPT.The mathematical model of PV array is simulated using in MATLAB/Simulink environment.Various...

  1. Biodegradation Behaviour of Thermoplastic Starch Films Derived from Tacca leontopetaloides Starch under Controlled Composting Condition

    Science.gov (United States)

    Amin, A. M. Mohd; Sauid, S. Mohd; Hamid, K. H. Ku; Musa, M.

    2018-05-01

    The biodegradation study of thermoplastic starch (TPS) films derived from Tacca leontopetaloides starch; namely TPS/GLY, TPS/ACE and TPS/BCHR were investigated under controlled composting conditions. A manual set-up test rig in laboratory scale was built according to ISO 14855-1: 2012. The biodegradation percentage was determined by measuring the amount of CO2 evolved using titration method and validated by automatic system (Arduino UNO System) that detected the CO2 evolved. After 45 days under controlled composting condition, results indicated that TPS/GLY degraded the fastest, followed by TPS/BCHR and the TPS/ACE had the slowest degradation. The biodegradation process of TPS/GLY, TPS/ACE and TPS/BCHR also exhibited two stages with different degradation speeds. From these results, it indicated that chemical modification of the TPS films by adding acetic acid and rice husk bio-char to the thermoplastic starch can have a major impact on the biodegradation rate and final biodegradation percentage.

  2. Testing the usefulness of 222Rn to complement conventional hydrochemical data to trace groundwater provenance in complex multi-layered aquifers. Application to the Úbeda aquifer system (Jaén, SE Spain).

    Science.gov (United States)

    Ortega, L; Manzano, M; Rodríguez-Arévalo, J

    2017-12-01

    The Úbeda aquifer system is a multi-layered aquifer intensively exploited for irrigation. It covers 1100km 2 and consists of piled up sedimentary aquifer and aquitard layers from Triassic sandstones and clays at the bottom, to Jurassic carbonates (main exploited layer) in the middle, and Miocene sandstones and marls at the top. Flow network modification by intense exploitation and the existence of deep faults favour vertical mixing of waters from different layers and with distinct chemical composition. This induces quality loss and fosters risk of quantity restrictions. To support future groundwater abstraction management, a hydrogeochemical (major and some minor solutes) and isotopic ( 222 Rn) study was performed to identify the chemical signatures of the different layers and their mixing proportions in mixed samples. The study of 134 groundwater samples allowed a preliminary identification of hydrochemical signatures and mixtures, but the existence of reducing conditions in the most exploited sector prevents the utility of sulphate as a tracer of Triassic groundwater in the Jurassic boreholes. The potential of 222 Rn to establish isotopic signatures and to trace groundwater provenance in mixtures was tested. 222 Rn was measured in 48 samples from springs and boreholes in most aquifer layers. At first, clear correlations were observed between 222 Rn, Cl and SO 4 in groundwater. Afterwards, very good correlations were observed between 222 Rn and the chemical facies of the different layers established with End Member Mixing Analysis (EMMA). Using 222 Rn as part of the signatures, EMMA helped to identify end-member samples, and to quantify the mixing proportions of water from the Triassic and the Deep Miocene layers in groundwater pumped by deep agricultural wells screened in the Jurassic. The incorporation of 222 Rn to the study also allowed identifying the impact of irrigation returns through the association of moderate NO 3 , Cl, and Br contents with very low 222

  3. Material Control and Accountability Experience at the Fuel Conditioning Facility

    International Nuclear Information System (INIS)

    Vaden, D.; Fredrickson, G.L.

    2007-01-01

    The Fuel Conditioning Facility (FCF) at the Idaho National Laboratory (INL) treats spent nuclear fuel using an electrometallurgical process that separates the uranium from the fission products, sodium thermal bond, and cladding materials. Material accountancy is necessary at FCF for two reasons: 1) it provides a mechanism for detecting a potential loss of nuclear material for safeguards and security, and 2) it provides a periodic check of inventories to ensure that processes and materials are within control limits. Material Control and Accountability is also a Department of Energy (DOE) requirement (DOE Order 474.1). The FCF employs a computer based Mass Tracking (MTG) System to collect, store, retrieve, and process data on all operations that directly affect the flow of materials through the FCF. The MTG System is important for the operations of the FCF because it supports activities such as material control and accountability, criticality safety, and process modeling. To conduct material control and accountability checks and to monitor process performance, mass balances are routinely performed around the process equipment. The equipment used in FCF for pyro-processing consists of two mechanical choppers and two electro-refiners (the Mark-IV with the accompanying element chopper and Mark-V with the accompanying blanket chopper for processing driver fuel and blanket, respectively), and a cathode processor (used for processing both driver fuel and blanket) and casting furnace (mostly used for processing driver fuel). Performing mass balances requires the measurement of the masses and compositions of several process streams and equipment inventories. The masses of process streams are obtained via in-cell balances (i.e., load cells) that weigh containers entering and leaving the process equipment. Samples taken at key locations are analyzed to determine the composition of process streams and equipment inventories. In cases where equipment or containers cannot be

  4. Conditions for settling liquid levels by means of gamma-ray relay control

    Energy Technology Data Exchange (ETDEWEB)

    Wakabayashi, N [Kobe Univ. (Japan). Faculty of Engineering

    1976-03-01

    Using a control action which consists of infusion and exhaust at constant speeds and a neutral zone to maintain liquid levels within a given range, a gamma-ray source, a detector, and two relays at the upper and lower limits of the counting rate were provided. The optimum condition in this case is discussed and confirmed experimentally. Since a counting rate-meter has a time constant and its output is subject to the statistical fluctuation, the liquid level may overrun the opposite limit, move again after settling within the range, or drift far out of the range by a load before actuation of the relay. Formulas are derived providing the conditions such that these phenomena will not occur more frequently than a tolerant probability. These give the relations between the counting rates at the upper and lower limits, the time constant of the rate-meter, the multipliers of the standard deviations of the counting rates, the infusing and exhausting speeds, and the hysteresis widths of the limiting relays. Since it can be said that the first two of the five quantities should be smaller and the next two greater, the optimum condition can be determined from the formulas. When the infusing and exhausting speeds are the same and the hysteresis widths are equal, the formulas show that the optimum is a case where the ratio of the counting rates at the two limits, which is taken smaller than unity, is small, and where each hysteresis width is equal to 0.34 times the difference between the two counting rates, almost regardless of the value of their ratio. The above-mentioned deductions were examined in a system constructed with a backscattered gamma-ray type level gauge and a controller for infusion and exhaust of water. Its results almost agreed with those of the deductions when the multipliers of the standard deviations are substituted for by 2.

  5. Control of first-wall surface conditions in the 2XIIB Magnetic Mirror Plasma Confinement experiment

    International Nuclear Information System (INIS)

    Simonen, T.C.; Bulmer, R.H.; Coensgen, F.H.

    1976-01-01

    The control of first-wall surface conditions in the 2XIIB Magnetic Mirror Plasma Confinement experiment is described. Before each plasma shot, the first wall is covered with a freshly gettered titanium surface. Up to 5 MW of neutral beam power has been injected into 2XIIB, resulting in first-wall bombardment fluxes of 10 17 atoms . cm -2 . s -1 of 13-keV mean energy deuterium atoms for several ms. The background gas flux is measured with a calibrated, 11-channel, fast-atom detector. Background gas levels are found to depend on surface conditions, injected beam current, and beam pulse duration. For our best operating conditions, an efective reflex coefficient of 0.3 can be inferred from the measurements. Experiments with long-duration and high-current beam injection are limited by charge exchange; however, experiments with shorter beam duration are not limited by first-wall surface conditions. It is concluded that surface effects will be reduced further with smoother walls. (Auth.)

  6. An Optimal Integrated Control Scheme for Permanent Magnet Synchronous Generator-Based Wind Turbines under Asymmetrical Grid Fault Conditions

    Directory of Open Access Journals (Sweden)

    Dan Wang

    2016-04-01

    Full Text Available In recent years, the increasing penetration level of wind energy into power systems has brought new issues and challenges. One of the main concerns is the issue of dynamic response capability during outer disturbance conditions, especially the fault-tolerance capability during asymmetrical faults. In order to improve the fault-tolerance and dynamic response capability under asymmetrical grid fault conditions, an optimal integrated control scheme for the grid-side voltage-source converter (VSC of direct-driven permanent magnet synchronous generator (PMSG-based wind turbine systems is proposed in this paper. The optimal control strategy includes a main controller and an additional controller. In the main controller, a double-loop controller based on differential flatness-based theory is designed for grid-side VSC. Two parts are involved in the design process of the flatness-based controller: the reference trajectories generation of flatness output and the implementation of the controller. In the additional control aspect, an auxiliary second harmonic compensation control loop based on an improved calculation method for grid-side instantaneous transmission power is designed by the quasi proportional resonant (Quasi-PR control principle, which is able to simultaneously restrain the second harmonic components in active power and reactive power injected into the grid without the respective calculation for current control references. Moreover, to reduce the DC-link overvoltage during grid faults, the mathematical model of DC-link voltage is analyzed and a feedforward modified control factor is added to the traditional DC voltage control loop in grid-side VSC. The effectiveness of the optimal control scheme is verified in PSCAD/EMTDC simulation software.

  7. Assessing the response of Emerald Lake, an alpine watershed in Sequoia National Park, California, to acidification during snowmelt by using a simple hydrochemical model

    International Nuclear Information System (INIS)

    Hooper, R.P.; West, C.T.; Peters, N.E.

    1990-01-01

    A sparsely parameterized hydrochemical model has been developed by using data from Emerald Lake watershed, which is a 120-ha alpine catchment in Sequoia National Park, California. Greater than 90% of the precipitation to this watershed is snow; hence, snowmelt is the dominant hydrologic event. A model which uses a single alkalinity-generating mechanism, primary mineral weathering, was able to capture the pattern of solute concentrations in surface waters during snowmelt. An empirical representation of the weathering reaction, which is based on rock weathering stoichiometry and which uses discharge as a measure of residence time, was included in the model. Results of the model indicate that current deposition levels would have to be increased between three-fold and eight-fold to exhaust the alkalinity of the lake during snowmelt if their is a mild acidic pulse in the stream at the beginning of snowmelt as was observed during the study period. The acidic pulse in the inflow stream at the onset of snowmelt was less pronounced than acidic pulses observed in the meltwater draining the snowpack at a point using snow lysimeters or in the laboratory. Sulfate concentrations in the stream water were the most constant; chloride and nitrate concentrations increased slightly at the beginning of snowmelt. Additional field work is required to resolve whether an acidic meltwater pulse occurs over a large area as well as at a point or whether, due to physical and chemical processes within the snowpack, the acidic meltwater pulse is attenuated at the catchment scale. The modest data requirements of the model permit its applications to other alpine watersheds that are much less intensively studied than Emerald Lake watershed

  8. Hydrochemical and isotopic characterization of the groundwater from the El Berrocal Site: Spain

    International Nuclear Information System (INIS)

    Gomez, P.; Turrero, M.J.; Martinez, B.; Melon, A.; Mingarro, M.; Rodriguez, V.; Gordienko, F.; Hernandez, A.; Crespo, M.T.

    1996-01-01

    The international El Berrocal Project is a multidisciplinary study of the processes controlling the migration of natural radionuclides in a fractured granitic environment. The initial phase of the Project started on 1 st March 1991 and ran for two years. The second phase started on 1 st March 1993 and ended in Mach 1995. The work was carried out jointly by five European Organisations, and was co-funded by ENRESA-CIEMAT (Spain) and the Commission of the European Communities (Project F12W-0080). The hydrogeochemical study has an important role in the El Berrocal Project Characterisation and Validation of Natural Radionuclide Migration Processes Under Real Conditions in a Fissured Granitic Environment, since it analyses the current water-rock interaction and natural radionuclide migration processes. The importance of this study and the difficulties involved in obtaining water samples representative of the system have certain influenced in the hydrogeochemical objectives El Berrocal. Outstanding among these objectives is the creation of basic infrastructures and the development of methodologies for the sampling, conservation and analysis of groundwaters, applicable to low permeability granitic media. (Author)

  9. Mental skills training effectively minimizes operative performance deterioration under stressful conditions: Results of a randomized controlled study.

    Science.gov (United States)

    Anton, N E; Beane, J; Yurco, A M; Howley, L D; Bean, E; Myers, E M; Stefanidis, D

    2018-02-01

    Stress can negatively impact surgical performance, but mental skills may help. We hypothesized that a comprehensive mental skills curriculum (MSC) would minimize resident performance deterioration under stress. Twenty-four residents were stratified then randomized to receive mental skills and FLS training (MSC group), or only FLS training (control group). Laparoscopic suturing skill was assessed on a live porcine model with and without external stressors. Outcomes were compared with t-tests. Twenty-three residents completed the study. The groups were similar at baseline. There were no differences in suturing at posttest or transfer test under normal conditions. Both groups experienced significantly decreased performance when stress was applied, but the MSC group significantly outperformed controls under stress. This MSC enabled residents to perform significantly better than controls in the simulated OR under unexpected stressful conditions. These findings support the use of psychological skills as an integral part of a surgical resident training. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Real-time corrosion monitoring of steel influenced by microbial activity (SRB) under controlled seawater injection conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kane, Russell D. [InterCorr International, Inc., 14503 Bammel N. Houston Road, Suite 300, Houston, TX 77019 (United States); Campbell, Scott [Commercial Microbiology Inc., 10400 Westoffice Drive Suite 107, Houston, TX 77042 (United States)

    2004-07-01

    An experimental study of microbiologically influenced corrosion (MIC) was conducted involving online, real-time monitoring of a bio-film loop under controlled conditions simulating oil field water handling and injection. Bio-film growth, MIC and biocide efficacy were monitored using an automated, multi-technique monitoring system including linear polarization resistance, electrochemical noise and harmonic distortion analysis. This data was correlated with conventional off-line methods to differentiate conditions of varying MIC activity in real-time to facilitate quick assessment and operator intervention. (authors)

  11. Very high gravity ethanol fermentation by flocculating yeast under redox potential-controlled conditions

    Directory of Open Access Journals (Sweden)

    Liu Chen-Guang

    2012-08-01

    Full Text Available Abstract Background Very high gravity (VHG fermentation using medium in excess of 250 g/L sugars for more than 15% (v ethanol can save energy consumption, not only for ethanol distillation, but also for distillage treatment; however, stuck fermentation with prolonged fermentation time and more sugars unfermented is the biggest challenge. Controlling redox potential (ORP during VHG fermentation benefits biomass accumulation and improvement of yeast cell viability that is affected by osmotic pressure and ethanol inhibition, enhancing ethanol productivity and yield, the most important techno-economic aspect of fuel ethanol production. Results Batch fermentation was performed under different ORP conditions using the flocculating yeast and media containing glucose of 201 ± 3.1, 252 ± 2.9 and 298 ± 3.8 g/L. Compared with ethanol fermentation by non-flocculating yeast, different ORP profiles were observed with the flocculating yeast due to the morphological change associated with the flocculation of yeast cells. When ORP was controlled at −100 mV, ethanol fermentation with the high gravity (HG media containing glucose of 201 ± 3.1 and 252 ± 2.9 g/L was completed at 32 and 56 h, respectively, producing 93.0 ± 1.3 and 120.0 ± 1.8 g/L ethanol, correspondingly. In contrast, there were 24.0 ± 0.4 and 17.0 ± 0.3 g/L glucose remained unfermented without ORP control. As high as 131.0 ± 1.8 g/L ethanol was produced at 72 h when ORP was controlled at −150 mV for the VHG fermentation with medium containing 298 ± 3.8 g/L glucose, since yeast cell viability was improved more significantly. Conclusions No lag phase was observed during ethanol fermentation with the flocculating yeast, and the implementation of ORP control improved ethanol productivity and yield. When ORP was controlled at −150 mV, more reducing power was available for yeast cells to survive, which in turn improved their viability and VHG

  12. Redox control of arsenic mobilization in Bangladesh groundwater

    International Nuclear Information System (INIS)

    Zheng, Y.; Stute, M.; Geen, A. van; Gavrieli, I.; Dhar, R.; Simpson, H.J.; Schlosser, P.; Ahmed, K.M.

    2004-01-01

    Detailed hydrochemical measurements, δ 34 S SO4 and 3 H analyses were performed on 37 groundwater samples collected during February 1999, January and March 2000 from 6 locations in eastern and southeastern Bangladesh to examine redox processes that lead to As mobilization in groundwater. The study sites were chosen based on available nation-wide As surveys to span the entire spectrum of As concentrations in Bangladesh groundwater, and to represent 3 of 5 major geological units of the Ganges-Brahmaputra Delta: uplifted Pleistocene terrace, fluvial flood plain and delta plain. Arsenic was found to be mobilized under Fe-reducing conditions in shallow aquifers ( 4 -reducing conditions, suggesting that authigenic sulfide precipitation does not constitute a significant sink for As in these groundwaters. The redox state of the water was characterized by a variety of parameters including dissolved O 2 , NO 3 - , Mn 2+ , Fe 2+ concentrations, and SO 4 2- /Cl - ratios. High dissolved [As] (> 50 μg/l; or > 0.7 μM ) were always accompanied by high dissolved [HCO 3 - ] (> 4 mM), and were close to saturation with respect to calcite. Groundwater enriched in As (200-800 μg/l; or 2.7-10.7 μM) and phosphate (30-100 μM) but relatively low in dissolved Fe (5-40 μM) probably resulted from re-oxidation of reducing, As and Fe enriched water. This history was deduced from isotopic signatures of δ 34 S SO4 and 3 H 2 O ( 3 H) to delineate the nature of redox changes for some of the reducing groundwaters. In contrast, As is not mobilized in presumed Pleistocene aquifers, both shallow (30-60 m) and deep (150-270 m), because conditions were not reducing enough due to lack of sufficient O 2 demand

  13. Complex dynamics and chaos control of duopoly Bertrand model in Chinese air-conditioning market

    International Nuclear Information System (INIS)

    Yi, Qi Guo; Zeng, Xiang Jin

    2015-01-01

    Highlights: •A dynamic duopoly Bertrand model with bounded rationality and quadratic cost function. •In Chinese air-conditioning market the boundary equilibrium point is locally stable. •The Lyapunov dimension of the chaos attractor is 1.9585. •The adjustment speeds may cause a market structure to behave chaotically. •The chaotic behavior can be controlled by decreasing the degree of substitutability. -- Abstract: A dynamic duopoly Bertrand model with quadratic cost function which is closer to reality and different from previous researches is discussed. The model is applied into air-conditioning market where the boundary equilibrium point is locally stable. Numerical simulations illustrate that the stability of Nash equilibrium strongly depends on the speed of adjustment of bounded rational player. The adjustment speeds and the degree of substitutability may undermine the stability of the equilibrium and cause a market structure to behave chaotically. The Lyapunov dimension of the chaos attractor is 1.9585 under some conditions. The stabilization of the chaotic behavior can be obtained by reducing the degree of substitutability. The results have an important theoretical and practical significance to Chinese air-conditioning market

  14. Conditional control in visual selection

    NARCIS (Netherlands)

    van Zoest, Wieske; Van der Stigchel, Stefan; Donk, Mieke

    2017-01-01

    Attention and eye movements provide a window into the selective processing of visual information. Evidence suggests that selection is influenced by various factors and is not always under the strategic control of the observer. The aims of this tutorial review are to give a brief introduction to eye

  15. Physics conditions for robust control of tearing modes in a rotating tokamak plasma

    Science.gov (United States)

    Lazzaro, E.; Borgogno, D.; Brunetti, D.; Comisso, L.; Fevrier, O.; Grasso, D.; Lutjens, H.; Maget, P.; Nowak, S.; Sauter, O.; Sozzi, C.; the EUROfusion MST1 Team

    2018-01-01

    The disruptive collapse of the current sustained equilibrium of a tokamak is perhaps the single most serious obstacle on the path toward controlled thermonuclear fusion. The current disruption is generally too fast to be identified early enough and tamed efficiently, and may be associated with a variety of initial perturbing events. However, a common feature of all disruptive events is that they proceed through the onset of magnetohydrodynamic instabilities and field reconnection processes developing magnetic islands, which eventually destroy the magnetic configuration. Therefore the avoidance and control of magnetic reconnection instabilities is of foremost importance and great attention is focused on the promising stabilization techniques based on localized rf power absorption and current drive. Here a short review is proposed of the key aspects of high power rf control schemes (specifically electron cyclotron heating and current drive) for tearing modes, considering also some effects of plasma rotation. From first principles physics considerations, new conditions are presented and discussed to achieve control of the tearing perturbations by means of high power ({P}{{EC}}≥slant {P}{{ohm}}) in regimes where strong nonlinear instabilities may be driven, such as secondary island structures, which can blur the detection and limit the control of the instabilities. Here we consider recent work that has motivated the search for the improvement of some traditional control strategies, namely the feedback schemes based on strict phase tracking of the propagating magnetic islands.

  16. Can timely vector control interventions triggered by atypical environmental conditions prevent malaria epidemics? A case-study from Wajir County, Kenya.

    Directory of Open Access Journals (Sweden)

    Peter Maes

    Full Text Available Atypical environmental conditions with drought followed by heavy rainfall and flooding in arid areas in sub-Saharan Africa can lead to explosive epidemics of malaria, which might be prevented through timely vector-control interventions.Wajir County in Northeast Kenya is classified as having seasonal malaria transmission. The aim of this study was to describe in Wajir town the environmental conditions, the scope and timing of vector-control interventions and the associated resulting burden of malaria at two time periods (1996-1998 and 2005-2007.This is a cross-sectional descriptive and ecological study using data collected for routine program monitoring and evaluation.In both time periods, there were atypical environmental conditions with drought and malnutrition followed by massive monthly rainfall resulting in flooding and animal/human Rift Valley Fever. In 1998, this was associated with a large and explosive malaria epidemic (weekly incidence rates peaking at 54/1,000 population/week with vector-control interventions starting over six months after the massive rainfall and when the malaria epidemic was abating. In 2007, vector-control interventions started sooner within about three months after the massive rainfall and no malaria epidemic was recorded with weekly malaria incidence rates never exceeding 0.5 per 1,000 population per week.Did timely vector-control interventions in Wajir town prevent a malaria epidemic? In 2007, the neighboring county of Garissa experienced similar climatic events as Wajir, but vector-control interventions started six months after the heavy un-seasonal rainfall and large scale flooding resulted in a malaria epidemic with monthly incidence rates peaking at 40/1,000 population. In conclusion, this study suggests that atypical environmental conditions can herald a malaria outbreak in certain settings. In turn, this should alert responsible stakeholders about the need to act rapidly and preemptively with appropriate

  17. On the potential for the Partial Triadic Analysis to grasp the spatio-temporal variability of groundwater hydrochemistry

    Science.gov (United States)

    Gourdol, L.; Hissler, C.; Pfister, L.

    2012-04-01

    instrument for hydrogeologists, in particular to characterize temporal and spatial hydrochemical variations induced by natural and anthropogenic factors. This new approach for groundwater management offers potential for 1) identifying a common multivariate spatial structure, 2) untapping the different hydrochemical patterns and explaining their controlling factors and 3) analysing the temporal variability of this structure and grasping hydrochemical changes.

  18. Ecology and living conditions of groundwater fauna

    Energy Technology Data Exchange (ETDEWEB)

    Thulin, Barbara [Geo Innova AB (Sweden); Hahn, Hans Juergen [Arbeitsgruppe Grundwasseroekologie, Univ. of Koblenz-Landau (Germany)

    2008-09-15

    This report presents the current state of ecological knowledge and applied research relating to groundwater. A conceptual picture is given of groundwater fauna occurrence in regard to Swedish environmental conditions. Interpretation features for groundwater fauna and applications are outlined. Groundwater is one of the largest and oldest limnic habitats populated by a rich and diverse fauna. Both very old species and species occurring naturally in brackish or salt water can be found in groundwater. Groundwater ecosystems are heterotrophic; the fauna depends on imports from the surface. Most species are meiofauna, 0.3-1 mm. The food chain of groundwater fauna is the same as for relatives in surface water and salt water. Smaller animals graze biofilms and detritus, larger animals act facutatively as predators. A difference is that stygobiotic fauna has become highly adapted to its living space and tolerates very long periods without food. Oxygen is a limiting factor, but groundwater fauna tolerates periods with low oxygen concentrations, even anoxic conditions. For longer periods of time a minimum oxygen requirement of 1 mg/l should be fulfilled. Geographic features such as Quaternary glaciation and very old Pliocene river systems are important for distribution patterns on a large spatial scale, but aquifer characteristics are important on a landscape scale. Area diversity is often comparable to surface water diversity. However, site diversity is low in groundwater. Site specific hydrological exchange on a geological facies level inside the aquifer, e.g. porous, fractured and karstic aquifers as well as the hyporheic zone, controls distribution patterns of groundwater fauna. For a better understanding of controlling factors indicator values are suggested. Different adequate sampling methods are available. They are representative for the aquifer, but a suitable number of monitoring wells is required. The existence of groundwater fauna in Sweden is considered as very

  19. Ecology and living conditions of groundwater fauna

    International Nuclear Information System (INIS)

    Thulin, Barbara; Hahn, Hans Juergen

    2008-09-01

    This report presents the current state of ecological knowledge and applied research relating to groundwater. A conceptual picture is given of groundwater fauna occurrence in regard to Swedish environmental conditions. Interpretation features for groundwater fauna and applications are outlined. Groundwater is one of the largest and oldest limnic habitats populated by a rich and diverse fauna. Both very old species and species occurring naturally in brackish or salt water can be found in groundwater. Groundwater ecosystems are heterotrophic; the fauna depends on imports from the surface. Most species are meiofauna, 0.3-1 mm. The food chain of groundwater fauna is the same as for relatives in surface water and salt water. Smaller animals graze biofilms and detritus, larger animals act facutatively as predators. A difference is that stygobiotic fauna has become highly adapted to its living space and tolerates very long periods without food. Oxygen is a limiting factor, but groundwater fauna tolerates periods with low oxygen concentrations, even anoxic conditions. For longer periods of time a minimum oxygen requirement of 1 mg/l should be fulfilled. Geographic features such as Quaternary glaciation and very old Pliocene river systems are important for distribution patterns on a large spatial scale, but aquifer characteristics are important on a landscape scale. Area diversity is often comparable to surface water diversity. However, site diversity is low in groundwater. Site specific hydrological exchange on a geological facies level inside the aquifer, e.g. porous, fractured and karstic aquifers as well as the hyporheic zone, controls distribution patterns of groundwater fauna. For a better understanding of controlling factors indicator values are suggested. Different adequate sampling methods are available. They are representative for the aquifer, but a suitable number of monitoring wells is required. The existence of groundwater fauna in Sweden is considered as very

  20. Fluoride characterization by principal component analysis in the hydrochemical facies of Serra Geral Aquifer System in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Arthur Nanni

    2008-12-01

    Full Text Available Principal component analysis is applied to 309 groundwater chemical data information from wells in the Serra Geral Aquifer System. Correlations among seven hydrochemical parameters are statistically examined. A four-component model is suggested and explains 81% of total variance. Component 1 represents calcium-magnesium bicarbonated groundwaters with long time of residence. Component 2 represents sulfated and chlorinated calcium and sodium groundwaters; Component 3 represents sodium bicarbonated groundwaters; and Component 4 is characterized by sodium sulfated with high fluoride facies. The components' spatial distribution shows high fluoride concentration along analyzed tectonic fault system and aligned on northeast direction in other areas, suggesting other hydrogeological fault systems. High fluoride concentration increases according to groundwater pumping depth. The Principal Component Analysis reveals features of the groundwater mixture and individualizes water facies. In this scenery, it can be determined hydrogeological blocks associated with tectonic fault system here introduced.A Análise de Componentes Principais foi aplicada em 309 dados químicos de águas subterrâneas de poços do Sistema Aqüífero Serra Geral. Correlações entre sete parâmetros hidroquímicos foram examinadas através da estatística. O modelo de quatro componentes foi utilizado por explicar 81% da variância total. A Componente 1 é representada por águas cálcio-magnesianas com longo tempo de residência, a Componente 2 representa águas bicarbonatadas sulfatadas e cloretadas, a Componente 3 representa águas bicarbonatadas sódicas e a Componente 4 é caracterizada por águas de fácies sódica e sulfatada com alto fluoreto. A distribuição espacial das componentes mostra águas com concentrações anômalas ao longo dos sistemas tectônicos de falhas, analisados e alinhados a NE em algumas áreas, sugerindo outros sistemas de falhas hidrogeológicos. As

  1. Non-enzymatic antioxidant accumulations in BR-deficient and BR-insensitive barley mutants under control and drought conditions.

    Science.gov (United States)

    Gruszka, Damian; Janeczko, Anna; Dziurka, Michal; Pociecha, Ewa; Fodor, Jozsef

    2017-12-07

    Drought is one of the most adverse stresses that affect plant growth and yield. Disturbances in metabolic activity resulting from drought cause overproduction of reactive oxygen species. It is postulated that brassinosteroids (BRs) regulate plant tolerance to the stress conditions, but the underlying mechanisms remain largely unknown. An involvement of endogenous BRs in regulation of the antioxidant homeostasis is not fully clarified either. Therefore, the aim of this study was to elucidate the role of endogenous BRs in regulation of non-enzymatic antioxidants in barley (Hordeum vulgare) under control and drought conditions. The plant material included the 'Bowman' cultivar and a group of semi-dwarf near-isogenic lines (NILs), representing mutants deficient in BR biosynthesis or signaling. In general, accumulations of 11 compounds representing various types of non-enzymatic antioxidants were analyzed under both conditions. The analyses of accumulations of reduced and oxidized forms of ascorbate indicated that the BR mutants contain significantly higher contents of dehydroascorbic acid under drought conditions when compared with the 'Bowman' cultivar. The analysis of glutathione accumulation indicated that under the control conditions the BR-insensitive NILs contained significantly lower concentrations of this antioxidant when compared with the rest of genotypes. Therefore, we postulate that BR sensitivity is required for normal accumulation of glutathione. A complete accumulation profile of various tocopherols indicated that functional BR biosynthesis and signaling are required for their normal accumulation under both conditions. Results of this study provided an insight into the role of endogenous BRs in regulation of the non-enzymatic antioxidant homeostasis. © 2017 Scandinavian Plant Physiology Society.

  2. Performance Investigation of Air Velocity Effects on PV Modules under Controlled Conditions

    Directory of Open Access Journals (Sweden)

    Muzaffar Ali

    2017-01-01

    Full Text Available Junction temperature of PV modules is one of the key parameters on which the performance of PV modules depends. In the present work, an experimental investigation was carried out to analyze the effects of air velocity on the performance of two PV modules, that is, monocrystalline silicon and polycrystalline silicon under the controlled conditions of a wind tunnel in the presence of an artificial solar simulator. The parameters investigated include the surface temperature variation, power output, and efficiency of PV modules under varying air velocity from near zero (indoor lab. conditions to 15 m/s. Additionally, the results were also determined at two different module angular positions: at 0° angle, that is, parallel to air direction and at 10° angle with the direction of coming air to consider the effects of tilt angles. Afterwards, the thermal analysis of the modules was performed using Ansys-Fluent in which junction temperature and heat flux of modules were determined by applying appropriate boundary conditions, such as air velocity, heat flux, and solar radiation. Finally, the numerical results are compared with the experiment in terms of junction temperatures of modules and good agreement was found. Additionally, the results showed that the maximum module temperature drops by 17.2°C and the module efficiency and power output increased from 10 to 12% with increasing air velocity.

  3. PRODUCTIVITY OF GROWING PONDS WHEN APPLYING THE BACTERIAL FERTILIZER «PHOSPHOBAKTERIN»

    Directory of Open Access Journals (Sweden)

    Т. Hryhorenko

    2017-09-01

    Full Text Available Purpose. To investigate the effect of the bacterial fertilizer "Phosphobacterin" on the formation of the hydrochemical regime, development of the natural food supply and fish productivity in the growing ponds. Methodology. The work was conducted according to generally accepted hydrochemical,, microbiological, hydrobiological and fish farming methods. Findings The article presents the results of a study of the productivity of growing ponds with different methods of the application of the bacterial fertilizer "Phosphobacterin". It was found that the hydrochemical regime of the experimental ponds was formed under the effect of the source of water supply and measures aimed at intensifying the development of the natural food supply and was favorable for the development of feed organisms and the cultivation of fish seeds. Application of the bacterial fertilizer at the beginning of the growing season along the water pond surface proved to be little effective for increasing the productivity of the pond ecosystem as a whole. A more effective method of increasing biological productivity, including fish productivity of growing ponds, was the application of "Phosphobacterin" during the growing season both on the bed and on the water surface in combination with the organic fertilizer - cattle humus. In the experimental pond under complex fertilization, the average phytoplankton biomass during the growing season was 1.5 times, bacterioplankton 1.1 times, zoobenthos 2.6 times higher, and the obtained total fish productivity was 1.2 times higher than in the control pond (when applying only cattle humus. Originality. The peculiarities of formation of hydrochemical and hydrobiological (phyto-, bacterio-, zooplankton, zoobenthos regimes of growing ponds and the fishery indices are studied, both for bacterial fertilizer "Phosphobacterin" independently and together with the traditional organic fertilizer - cattle humus. Practical value. Based on the obtained results

  4. 78 FR 11554 - Special Conditions: Embraer S.A., Model EMB-550 Airplane, Limit Pilot Forces for Sidestick Control

    Science.gov (United States)

    2013-02-19

    ... approximately 6,540 pounds of thrust for normal takeoff. The primary flight controls consist of hydraulically... FAA must issue a finding of regulatory adequacy under section 611 of Public Law 92-574, the ``Noise Control Act of 1972.'' The FAA issues special conditions, as defined in 14 CFR 11.19, in accordance with...

  5. Hot-Fire Testing of 100 LB(sub F) LOX/LCH4 Reaction Control Engine at Altitude Conditions

    Science.gov (United States)

    Marshall, William M.; Kleinhenz, Julie E.

    2010-01-01

    Liquid oxygen/liquid methane (LO2/LCH4 ) has recently been viewed as a potential green propulsion system for both the Altair ascent main engine (AME) and reaction control system (RCS). The Propulsion and Cryogenic Advanced Development Project (PCAD) has been tasked by NASA to develop these green propellant systems to enable safe and cost effective exploration missions. However, experience with LO2/LCH4 as a propellant combination is limited, so testing of these systems is critical to demonstrating reliable ignition and performance. A test program of a 100 lb f reaction control engine (RCE) is underway at the Altitude Combustion Stand (ACS) of the NASA Glenn Research Center, with a focus on conducting tests at altitude conditions. These tests include a unique propellant conditioning feed system (PCFS) which allows for the inlet conditions of the propellant to be varied to test warm to subcooled liquid propellant temperatures. Engine performance, including thrust, c* and vacuum specific impulse (I(sub sp,vac)) will be presented as a function of propellant temperature conditions. In general, the engine performed as expected, with higher performance at warmer propellant temperatures but better efficiency at lower propellant temperatures. Mixture ratio effects were inconclusive within the uncertainty bands of data, but qualitatively showed higher performance at lower ratios.

  6. Bayesian Sampling using Condition Indicators

    DEFF Research Database (Denmark)

    Faber, Michael H.; Sørensen, John Dalsgaard

    2002-01-01

    of condition indicators introduced by Benjamin and Cornell (1970) a Bayesian approach to quality control is formulated. The formulation is then extended to the case where the quality control is based on sampling of indirect information about the condition of the components, i.e. condition indicators...

  7. Control Strategy of Three-Phase Photovoltaic Inverter under Low-Voltage Ride-Through Condition

    Directory of Open Access Journals (Sweden)

    Xianbo Wang

    2015-01-01

    Full Text Available The new energy promoting community has recently witnessed a surge of developments in photovoltaic power generation technologies. To fulfill the grid code requirement of photovoltaic inverter under low-voltage ride-through (LVRT condition, by utilizing the asymmetry feature of grid voltage, this paper aims to control both restraining negative sequence current and reactive power fluctuation on grid side to maintain balanced output of inverter. Two mathematical inverter models of grid-connected inverter containing LCL grid-side filter under both symmetrical and asymmetric grid are proposed. PR controller method is put forward based on inverter model under asymmetric grid. To ensure the stable operation of the inverter, grid voltage feedforward method is introduced to restrain current shock at the moment of voltage drop. Stable grid-connected operation and LVRT ability at grid drop have been achieved via a combination of rapid positive and negative sequence component extraction of accurate grid voltage synchronizing signals. Simulation and experimental results have verified the superior effectiveness of our proposed control strategy.

  8. Hydrogeological processes controlling water quality in the crystalline basement aquifer of the Vea Catchment in Northeast Ghana

    Science.gov (United States)

    Koffi, K. V.; Obuobie, E.; Banning, A.; Wohnlich, S.

    2016-12-01

    In the Vea catchment of Northeast Ghana, groundwater appears to be a good alternative source for domestic and agricultural water supply as surface water is largely unavailable in the prolonged dry season that characterises this semi-arid area underlain by a crystalline rock aquifer. But the usability of water depends on its quality and therefore this study was done to investigate the processes influencing groundwater hydrochemistry in the study area to inform sustainable development and use of the resource. Sixty one groundwater samples were collected from different lithologies of the crystalline aquifer, and analysed for hydrochemical and physico-chemical parameters. Results show that groundwater chemistry is governed by rock-water interaction in the area. It is mainly controlled by cation exchange and silicate weathering processes. The majority of the samples was found to cluster in the Ca-Mg-HCO3 water type, regardless of aquifer geology. From a hydrochemistry perspective, the groundwater in the area is generally suitable for irrigation and drinking purposes.

  9. Exploring valid internal-control genes in Porphyra yezoensis (Bangiaceae) during stress response conditions

    Science.gov (United States)

    Wang, Wenlei; Wu, Xiaojie; Wang, Chao; Jia, Zhaojun; He, Linwen; Wei, Yifan; Niu, Jianfeng; Wang, Guangce

    2014-07-01

    To screen the stable expression genes related to the stress (strong light, dehydration and temperature shock) we applied Absolute real-time PCR technology to determine the transcription numbers of the selected test genes in P orphyra yezoensis, which has been regarded as a potential model species responding the stress conditions in the intertidal. Absolute real-time PCR technology was applied to determine the transcription numbers of the selected test genes in P orphyra yezoensis, which has been regarded as a potential model species in stress responding. According to the results of photosynthesis parameters, we observed that Y(II) and F v/ F m were significantly affected when stress was imposed on the thalli of P orphyra yezoensis, but underwent almost completely recovered under normal conditions, which were collected for the following experiments. Then three samples, which were treated with different grade stresses combined with salinity, irradiation and temperature, were collected. The transcription numbers of seven constitutive expression genes in above samples were determined after RNA extraction and cDNA synthesis. Finally, a general insight into the selection of internal control genes during stress response was obtained. We found that there were no obvious effects in terms of salinity stress (at salinity 90) on transcription of most genes used in the study. The 18S ribosomal RNA gene had the highest expression level, varying remarkably among different tested groups. RPS8 expression showed a high irregular variance between samples. GAPDH presented comparatively stable expression and could thus be selected as the internal control. EF-1α showed stable expression during the series of multiple-stress tests. Our research provided available references for the selection of internal control genes for transcripts determination of P. yezoensis.

  10. Analysis of the Impact of Urban Microclimate on Air Conditioning Load Control

    Directory of Open Access Journals (Sweden)

    Hu Xiaoqing

    2016-01-01

    Full Text Available Due to the presence of urban heat island effect (UHIE, high humidity and other urban microclimate, temperature of city central area rises. This causes that the actual air-conditioning energy consumption (ACEC in the urban central area is much higher than that in the suburbs. Load control of air-conditioners (ACs is considered to be equivalent to a power plant of the same capacity, and it can greatly reduce the system pressure to peak load shift. In this paper, a simplified second order transfer function control model of ACs is presented, and its parameters will be influenced by the ambient temperature and urban microclimate. The temperature is obtained by using the temperature inversion algorithm of the heat island effect. Then, the heat index is calculated by combining temperature and humidity. The ambient temperature index of urban central area is modified based on the above microclimate, and the second order linear time invariant model of aggregated ACs is upgraded to the linear time varying model. Furthermore, the consequent parameter changes of the second order transfer function model are studied and the influence of urban microclimate on AC load control is analyzed. The proposed method is verified on numerical examples

  11. Forsmark site investigation. Hydrochemical investigations in four calciferous lakes in the Forsmark area. Results from the second year of a complementary investigation in the Forsmark area

    International Nuclear Information System (INIS)

    Qvarfordt, Susanne; Borgiel, Micke; Berg, Cecilia

    2011-12-01

    The present report documents the results from the second year of hydrochemical investigations in four small, calciferous lakes in the Forsmark area in order to study the lake water compositions. The construction of a permanent storage facility for used nuclear fuel may result in a lowering of the ground water level and also lake surface water levels. Restoration of habitats by adding water may be an option to reduce possible negative consequences induced by a lower water level on biodiversity and valuable species. Thus, knowledge of the water composition is needed. This report presents the results from six sampling occasions during January to December 2010. The results from the sampling of the four lakes includes field measurements of redox potential (ORP), pH, dissolved oxygen, electrical conductivity, salinity, depth, atmospheric pressure, turbidity, chlorophyll and water temperature, as well as chemical analyses of major constituents and nutrient salts. The four investigated small lakes are well buffered with high alkalinity, high pH and high calcium concentrations. This is in accordance with results from the ongoing monitoring programme of lakes and streams in the area and with the results from the previous sampling period (2008-2009). The results show both seasonal and inter-annual variation in the analysed parameters. This can be explained by seasonal changes and annual differences in temperature, ice-cover, precipitation etc and lake specific parameters such as lake size and drainage area. The variation highlights the importance of both year round sampling and continued sampling for several years when discussing the water composition

  12. Forsmark site investigation. Hydrochemical investigations in four calciferous lakes in the Forsmark area. Results from the second year of a complementary investigation in the Forsmark area

    Energy Technology Data Exchange (ETDEWEB)

    Qvarfordt, Susanne; Borgiel, Micke [Sveriges Vattenekologer AB, Vingaaker (Sweden); Berg, Cecilia [Geosigma AB, Uppsala (Sweden)

    2011-12-15

    The present report documents the results from the second year of hydrochemical investigations in four small, calciferous lakes in the Forsmark area in order to study the lake water compositions. The construction of a permanent storage facility for used nuclear fuel may result in a lowering of the ground water level and also lake surface water levels. Restoration of habitats by adding water may be an option to reduce possible negative consequences induced by a lower water level on biodiversity and valuable species. Thus, knowledge of the water composition is needed. This report presents the results from six sampling occasions during January to December 2010. The results from the sampling of the four lakes includes field measurements of redox potential (ORP), pH, dissolved oxygen, electrical conductivity, salinity, depth, atmospheric pressure, turbidity, chlorophyll and water temperature, as well as chemical analyses of major constituents and nutrient salts. The four investigated small lakes are well buffered with high alkalinity, high pH and high calcium concentrations. This is in accordance with results from the ongoing monitoring programme of lakes and streams in the area and with the results from the previous sampling period (2008-2009). The results show both seasonal and inter-annual variation in the analysed parameters. This can be explained by seasonal changes and annual differences in temperature, ice-cover, precipitation etc and lake specific parameters such as lake size and drainage area. The variation highlights the importance of both year round sampling and continued sampling for several years when discussing the water composition.

  13. Hydrogeology and water chemistry of Infranz catchment springs, Bahir Dar Area, Lake Tana Basin, Ethiopia

    Science.gov (United States)

    Abera, F. N.

    2017-12-01

    The major springs in the Infranz catchment are a significant source of water for Bahir city and nearby villages, while they help to sustain Infranz River and the downstream wetlands. The aim of the research was to understand the hydrogeological conditions of these high-discharge springs, and to explain the hydrochemical composition of spring waters. Water samples from rainwater and springs were collected and analyzed and compared for major cations and anions. The hydrochemical data analysis showed that all water samples of the springs have freshwater chemistry, Ca-HCO3 type, while deep groundwater shows more evolved types. This indicates limited water-rock interaction and short residence time for the spring waters. The rise of NO3- and PO43- may indicate future water quality degradation unless the anthropogenic activities upgradient and nearby are restricted. The uptake of 75% of spring water for water supply of Bahir Dar results in wetland degradation. Key words: Spring water, Infranz River, Bahir Dar, Ethiopia, hydrochemistry

  14. Control of grid integrated voltage source converters under unbalanced conditions: development of an on-line frequency-adaptive virtual flux-based approach

    Energy Technology Data Exchange (ETDEWEB)

    Suul, Jon Are

    2012-03-15

    Three-Phase Voltage Source Converters (VSCs) are finding widespread applications in grid integrated power conversion systems. The control systems of such VSCs are in an increasing number of these applications required to operate during voltage disturbances and unbalanced conditions. Control systems designed for grid side voltagesensor-less operation are at the same time becoming attractive due to the continuous drive for cost reduction and increased reliability of VSCs, but are not commonly applied for operation during unbalanced conditions. Methods for voltage-sensor-less grid synchronization and control of VSCs under unbalanced grid voltage conditions will therefore be the main focus of this Thesis. Estimation methods based on the concept of Virtual Flux, considering the integral of the converter voltage in analogy to the flux of an electric machine, are among the simplest and most well known techniques for achieving voltage-sensor-less grid synchronization. Most of the established techniques for Virtual Flux estimation are, however, either sensitive to grid frequency variations or they are not easily adaptable for operation under unbalanced grid voltage conditions. This Thesis addresses both these issues by proposing a simple approach for Virtual Flux estimation by utilizing a frequency-adaptive filter based on a Second Order Generalized Integrator (SOGI). The proposed approach can be used to achieve on-line frequency-adaptive varieties of conventional strategies for Virtual Flux estimation. The main advantage is, however, that the SOGI-based Virtual Flux estimation can be arranged in a structure that achieves inherent symmetrical component sequence separation under unbalanced conditions. The proposed method for Virtual Flux estimation can be used as a general basis for voltage-sensor-less grid synchronization and control during unbalanced conditions. In this Thesis, the estimated Virtual Flux signals are used to develop a flexible strategy for control of active

  15. Combined heat and gamma-irradiation treatments for the control of strawberry diseases under market conditions

    International Nuclear Information System (INIS)

    Brodrick, H.T.; Thomas, A.C.; Van Tonder, A.J.; Terblanche, J.C.

    1977-02-01

    The spoilage of strawberries under local market conditions was investigated. It was confirmed that the major losses are due to 'leak' disease caused by Rhizopus stolonifer (Ehr. ex Fr.) Lind. It was also established that further fruit losses in summer are due to anthracnose caused by the fungus Colletotrichum acutatum Simmonds. This is the first time that the latter pathogen has been isolated and identified and recognised as a problem on strawberries in South Africa. Studies with R. stolonifer in culture showed that 46 degrees Celsius for 20 min (the previous international standard heat treatment for fruit) was disappointing, while a treatment at 50 degrees Celsius for 10 min effectively inhibited spore germination. Irradiation studies with cultures of R. stolonifer and C. acutatum showed that a dose of 200 and 100 krad, respectively, resulted in excellent inhibition of spore germination. However, irradiating in nitrogen gas resulted in a tenfold reduction in the effectiveness of the irradiation treatments. The use of nitrogen during irradiation, therefore, cannot be considered, especially where an effective control of the fungal pathogens is desired. Investigations with different cultivars clearly demonstrated the synergistic effect on disease control obtained when combining heat and irradiation treatments. The combination treatment (moist heat at 50-52 degrees Celsius for 10 min plus 200 krad), besides effectively controlling both diseases in strawberries, did not adversely affect berry quality. In simulated transport tests it was shown that a minimal amount of berry softening did occur with this treatment, but this adverse effect was negligible compared with the beneficial effect obtained from disease control. In semi-commercial experiments it was shown that the combination heat and irradiation treatment effectively controlled spoilage diseases for a period of several days from picking, thus allowing sufficient time to market the fruit under local market

  16. New insight into defining the lakes of the southern Baltic coastal zone.

    Science.gov (United States)

    Cieśliński, Roman; Olszewska, Alicja

    2018-01-29

    There exist many classification systems of hydrographic entities such as lakes found along the coastlines of seas and oceans. Each system has its advantages and can be used with some success in the area of protection and management. This paper aims to evaluate whether the studied lakes are only coastal lakes or rather bodies of water of a completely different hydrological and hydrochemical nature. The attempt to create a new classification system of Polish coastal lakes is related to the incompleteness of lake information in existing classifications. Thus far, the most frequently used are classifications based solely on lake basin morphogenesis or hydrochemical properties. The classifications in this paper are based not only on the magnitude of lake water salinity or hydrochemical analysis but also on isolation from the Baltic Sea and other sources of water. The key element of the new classification system for coastal bodies of water is a departure from the existing system used to classify lakes in Poland and the introduction of ion-"tracking" methods designed to identify anion and cation distributions in each body of water of interest. As a result of the work, a new classification of lakes of the southern Baltic Sea coastal zone was created. Featured objects such as permanently brackish lakes, brackish lakes that may turn into freshwater lakes from time to time, freshwater lakes that may turn into brackish lakes from time to time, freshwater lakes that experience low levels of salinity due to specific incidents, and permanently freshwater lakes. The authors have adopted 200 mg Cl -  dm -3 as a maximum value of lake water salinity. There are many conditions that determine the membership of a lake to a particular group, but the most important is the isolation lakes from the Baltic Sea. Changing a condition may change the classification of a lake.

  17. Coordinated control of a DFIG-based wind-power generation system with SGSC under distorted grid voltage conditions

    DEFF Research Database (Denmark)

    Yao, Jun; Li, Qing; Chen, Zhe

    2013-01-01

    in the multiple synchronous rotating reference frames. In order to counteract the adverse effects of the voltage harmonics upon the DFIG, the SGSC generates series compensation control voltages to keep the stator voltage sinusoidal and symmetrical, which allows the use of the conventional vector control strategy......This paper presents a coordinated control method for a doubly-fed induction generator (DFIG)-based wind-power generation system with a series grid-side converter (SGSC) under distorted grid voltage conditions. The detailed mathematical models of the DFIG system with SGSC are developed...

  18. Controlling Structural Characteristics of Single-Walled Carbon Nanotubes (SWNT) by Tailoring Catalyst Composition and Synthesis Conditions

    International Nuclear Information System (INIS)

    Resasco, Daniel E.

    2010-01-01

    This report shows the extensive research on the mechanism responsible for the formation of single walled carbon nanotubes in order to get control over their structural parameters (diameter and chirality). Catalyst formulations, pre-treatment conditions, and reaction conditions are described in detail as well as mechanisms to produce nanotubes structures of specific arrays (vertical forest, nanotube pillars). Applications of SWNT in different fields are also described in this report. In relation to this project five students have graduated (3 PhD and 2 MS) and 35 papers have been published.

  19. Autonomous tracked robots in planar off-road conditions modelling, localization, and motion control

    CERN Document Server

    González, Ramón; Guzmán, José Luis

    2014-01-01

    This monograph is framed within the context of off-road mobile robotics. In particular, it discusses issues related to modelling, localization, and motion control of tracked mobile robots working in planar slippery conditions. Tracked locomotion constitutes a well-known solution for mobile platforms operating over diverse challenging terrains, for that reason, tracked robotics constitutes an important research field with many applications (e.g. agriculture, mining, search and rescue operations, military activities). The specific topics of this monograph are: historical perspective of tracked vehicles and tracked robots; trajectory-tracking model taking into account slip effect; visual-odometry-based localization strategies; and advanced slip-compensation motion controllers ensuring efficient real-time execution. Physical experiments with a real tracked robot are presented showing the better performance of the suggested novel approaches to known techniques.   Keywords: longitudinal slip, visual odometry, slip...

  20. ANALYSIS OF INDIVIDUAL BIOLOGICAL CHARACTERISTICS OF AMUR CARP (CYPRINUS CARPIO HAEMATOPTERUS REPRODUCED USING CRYOPRESERVED SPERM

    Directory of Open Access Journals (Sweden)

    N. Kolisnyk

    2014-12-01

    Full Text Available Purpose. To reproduce Amur carp population using cryopreserved sperm and analyze some biological and fish culture peculiarities of the reproduced fish stock. Methodology. Generally accepted methods for fish culture [1]. Experimental reproduction was carried out in pond conditions of «Carpathian vodogray» LTD (Lisnevychi village, Pustomytivsky district, Lviv region. Hydrochemical analysis was carried out classically by O. Alуokin (1970 [2], hydrobiological studies in the fatting ponds according to V. Zhadin (1956, 1960 [3, 4]. Haemoglobin concentration was determined by hemocyanin method of G. Dervis, A. Vorobiov [5]. Blood for this method was collected from fish heart with the use of Pasteur pipettes in Eppendorf tubes with heparin. Following exterior morphometric parameters were analysed: body weight (m, g, standard fish body length (l, cm, largest body height (H, cm and body circumference (O cm. Following exterior indices were calculated based on these parameters: body depth index (l/H, body circumference index (l/O and Fulton’s condition factor (Kv. The study was carried out using two groups of carp: control and experimental. The first group was reproduced from the native sperm, the second from the cryopreserved sperm. Findings. Carp reproduction and growing was carried out using native and cryopreserved sperm. This work contains the results of growing 1+ Amur carp of experimental and control groups. Hydrochemical and hydrobiological parameters of the fattening ponds were studied. Peculiarities of the exterior and some hematological parameters of the carp of different origin were characterized. Originality. For the first time we performed a comparison of some biological parameters of Amur carp reproduced using native and cryopreserved sperm. Practical Value. Considering the economic importance of Amur carp due to its use in hybridization, reproduction of its population plays an important role in the development of the stocks of the pure

  1. Hydrodynamic or hydrochemical aspects of anthropogenic and naturally induced bank filtration - examples from Berlin/Brandenburg; Hydrodynamische und hydrochemische Aspekte der anthropogen und natuerlich induzierten Uferfiltration am Beispiel von Berlin/Brandenburg

    Energy Technology Data Exchange (ETDEWEB)

    Massmann, G.; Pekdeger, A. [Freie Universitaet Berlin (Germany). Institut fuer Geologische Wissenschaften, Arbeitsbereich Hydrogeologie; Duennbier, U. [Berliner Wasserbetriebe, Labor, Berlin (Germany); Heberer, T. [Niedersaechsisches Landesamt fuer Verbraucherschutz und Lebensmittelsicherheit (LAVES), Lebensmittelinstitut Oldenburg (Germany); Richter, D. [DVGW - Technologiezentrum Wasser (TZW), Karlsruhe (Germany); Sueltenfuss, J. [Universitaet Bremen (Germany). Institut fuer Umweltphysik, AG Ozeanographie; Tosaki, Y. [University of Tsukuba (Japan). Sustainable Environmental Studies, Graduate School of Life and Environmental Sciences

    2009-09-15

    Bank filtration is the natural or anthropogenically induced process of surface water infiltration into an aquifer. It is of particular importance as a method to gain or pre-treat water for drinking water production. The hydrodynamic and hydrochemical processes during bank filtration were investigated at one rural site in the Oderbruch and at two urban sites in Berlin (Germany). Results show that these sites differ substantially with regard to the characteristics of the hyporheic zone (permeable versus clogged), travel times (decades versus months to decades) and shape of the redox zones (horizontal versus vertical redox succession). The hyporheic zone is a key parameter determining the site characteristics. Since the surface water in Berlin contains a proportion of treated sewage, a number of wastewater-bound substances (e. g. pharmaceutical residues) have been detected in the surface water. Most of them were, however, fully or partly removed during bank filtration. The redox conditions are an important key parameter with regard to the elimination (or persistence) of a number of organic trace compounds (e. g. phenazone, sulfamethoxazole, clindamycin), whose elimination depends on the prevailing redox environment. (orig.) [German] Uferfiltration ist die natuerlich bedingte oder anthropogen induzierte Infiltration von Oberflaechenwasser in den Grundwasserleiter und ist insbesondere als Methode der Rohwassergewinnung fuer die Trinkwasserproduktion von Bedeutung. Die hydrodynamischen und hydrochemischen Prozesse bei der Uferfiltration wurden an einer Untersuchungstransekte im laendlichen Oderbruch und an zwei Transekten im urbanen Berlin umfangreich untersucht, dabei lag ein Schwerpunkt auf der Anwendung verschiedener Tracermethoden. Die Ergebnisse zeigen, dass sich die Standorte sehr stark insbesondere bezueglich der Beschaffenheit der Gewaessersohle (gut bzw. schlecht durchlaessig), der Fliesszeiten (Jahrzehnte bzw. Monate bis Jahrzehnte) und der Ausbildung von

  2. Cooling water conditioning and quality control for tokamaks

    International Nuclear Information System (INIS)

    Gootgeld, A.M.

    1995-01-01

    Designers and operators of Tokamaks and all associated water cooled, peripheral equipment, are faced with the task of providing and maintaining closed-loop, low conductivity, low impurity, cooling water systems. The primary reason for supplying low conductivity water to the DIII-D vacuum vessel coils, power supplies and auxiliary heating components is to assure, along with the use of a non-conducting break in the supply piping, sufficient electrical resistance and thus an acceptable current-leakage path to ground at operating voltage potentials. As important, good quality cooling water significantly reduces the likelihood of scaling and fouling of flow passages and heat transfer surfaces. Dissolved oxygen gas removal is also required in one major DIII-D cooling water system to minimize corrosion in the ion sources of the neutral beam injectors. Currently, the combined pumping capacity of the high quality cooling water systems at DIII-D is ∼5,000 gpm. Another area that receives close attention at DIII-D is the chemical treatment of the water used in the cooling towers. This paper discusses the DIII-D water quality requirements, the means used to obtain the necessary quality and the instrumentation used for control and monitoring. Costs to mechanically and chemically condition and maintain water quality are discussed as well as the various aspects of complying with government standards and regulations

  3. Elicitors as alternative strategy to pesticides in grapevine? Current knowledge on their mode of action from controlled conditions to vineyard.

    Science.gov (United States)

    Delaunois, Bertrand; Farace, Giovanni; Jeandet, Philippe; Clément, Christophe; Baillieul, Fabienne; Dorey, Stéphan; Cordelier, Sylvain

    2014-04-01

    Development and optimisation of alternative strategies to reduce the use of classic chemical inputs for protection against diseases in vineyard is becoming a necessity. Among these strategies, one of the most promising consists in the stimulation and/or potentiation of the grapevine defence responses by the means of elicitors. Elicitors are highly diverse molecules both in nature and origins. This review aims at providing an overview of the current knowledge on these molecules and will highlight their potential efficacy from the laboratory in controlled conditions to vineyards. Recent findings and concepts (especially on plant innate immunity) and the new terminology (microbe-associated molecular patterns, effectors, etc.) are also discussed in this context. Other objectives of this review are to highlight the difficulty of transferring elicitors use and results from the controlled conditions to the vineyard, to determine their practical and effective use in viticulture and to propose ideas for improving their efficacy in non-controlled conditions.

  4. Rapid and tunable method to temporally control gene editing based on conditional Cas9 stabilization. | Office of Cancer Genomics

    Science.gov (United States)

    The CRISPR/Cas9 system is a powerful tool for studying gene function. Here, we describe a method that allows temporal control of CRISPR/Cas9 activity based on conditional Cas9 destabilization. We demonstrate that fusing an FKBP12-derived destabilizing domain to Cas9 (DD-Cas9) enables conditional Cas9 expression and temporal control of gene editing in the presence of an FKBP12 synthetic ligand. This system can be easily adapted to co-express, from the same promoter, DD-Cas9 with any other gene of interest without co-modulation of the latter.

  5. A control strategy for grid-side converter of DFIG under unbalanced condition based on Dig SILENT/Power Factory

    Science.gov (United States)

    Han, Pingping; Zhang, Haitian; Chen, Lingqi; Zhang, Xiaoan

    2018-01-01

    The models of doubly fed induction generator (DFIG) and its grid-side converter (GSC) are established under unbalanced grid condition based on DIgSILENT/PowerFactory. According to the mathematical model, the vector equations of positive and negative sequence voltage and current are deduced in the positive sequence synchronous rotating reference frame d-q-0 when the characteristics of the simulation software are considered adequately. Moreover, the reference value of current component of GSC in the positive sequence frame d-q-0 under unbalanced condition can be obtained to improve the traditional control of GSC when the national issue of unbalanced current limits is combined. The simulated results indicate that the control strategy can restrain negative sequence current and the two times frequency power wave of GSC’s ac side effectively. The voltage of DC bus can be maintained a constant to ensure the uninterrupted operation of DFIG under unbalanced grid condition eventually.

  6. Assessing the hydrogeochemical processes affecting groundwater pollution in arid areas using an integration of geochemical equilibrium and multivariate statistical techniques.

    Science.gov (United States)

    El Alfy, Mohamed; Lashin, Aref; Abdalla, Fathy; Al-Bassam, Abdulaziz

    2017-10-01

    Rapid economic expansion poses serious problems for groundwater resources in arid areas, which typically have high rates of groundwater depletion. In this study, integration of hydrochemical investigations involving chemical and statistical analyses are conducted to assess the factors controlling hydrochemistry and potential pollution in an arid region. Fifty-four groundwater samples were collected from the Dhurma aquifer in Saudi Arabia, and twenty-one physicochemical variables were examined for each sample. Spatial patterns of salinity and nitrate were mapped using fitted variograms. The nitrate spatial distribution shows that nitrate pollution is a persistent problem affecting a wide area of the aquifer. The hydrochemical investigations and cluster analysis reveal four significant clusters of groundwater zones. Five main factors were extracted, which explain >77% of the total data variance. These factors indicated that the chemical characteristics of the groundwater were influenced by rock-water interactions and anthropogenic factors. The identified clusters and factors were validated with hydrochemical investigations. The geogenic factors include the dissolution of various minerals (calcite, aragonite, gypsum, anhydrite, halite and fluorite) and ion exchange processes. The anthropogenic factors include the impact of irrigation return flows and the application of potassium, nitrate, and phosphate fertilizers. Over time, these anthropogenic factors will most likely contribute to further declines in groundwater quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Research and application of an intelligent control system in central air-conditioning based on energy consumption simulation

    Science.gov (United States)

    Cao, Ling; Che, Wenbin

    2018-05-01

    For the central air-conditioning energy-saving, it is common practice to use a wide range of PTD controllers in engineering to optimize energy savings. However, the shortcomings of the PTD controller have also been magnified on this issue, such as: calculation accuracy is not enough, the calculation time is too long. Particle swarm optimization has the advantage of fast convergence. This paper is based on Particle Swarm Optimization apply in PTD controller tuning parameters in order to achieve the purpose of saving energy while ensuring comfort. The algorithm proposed in this paper can adjust the weight according to the change of population fitness, reduce the weights of particles with lower fitness and enhance the weights of particles with higher fitness in the population, and fully release the population vitality. The method in this paper is validated by the TRNSYS model based on the central air-conditioning system. The experimental results show that the room temperature fluctuation is small, the overshoot is small, the adjustment speed is fast, and the energy-saving fluctuates at 10%.

  8. Preliminary Borehole Disposal In Medium Flow Hydrogeological Condition Using IAEA Screening Tools

    International Nuclear Information System (INIS)

    Nazran Harun; Mohd Abd Wahab Yusof; Norasalwa Zakaria; Mohd Zaidi Ibrahim; Muhammad Fathi Sujan

    2014-01-01

    A screening tool developed by International Atomic Energy Agency (IAEA) has been used to provide means of improving the capacity of Malaysian Nuclear Agency (Nuclear Malaysia) in assessing the potential sites for Borehole Disposal for Disused Sealed Radioactive Sources. It allows the isolation provided by the capsule and disposal container to be evaluated. In addition, it has a conservative model of radionuclide transport with no retardation of radionuclide. Hence, rapid decisions can be made by providing an early indication of the potential suitability of sites based on their hydro-chemical characteristics. The objective of this paper is to identify and determine the types and radionuclide activities of inventory that can be disposed in the borehole. The results of the analysis show the volume of gas doses occur from the disposal and time taken for the cement to be corroded. (author)

  9. Analysis and Optimal Condition of the Rear-Sound-Aided Control Source in Active Noise Control

    Directory of Open Access Journals (Sweden)

    Karel Kreuter

    2011-01-01

    Full Text Available An active noise control scenario of simple ducts is considered. The previously suggested technique of using an single loudspeaker and its rear sound to cancel the upstream sound is further examined and compared to the bidirectional solution in order to give theoretical proof of its advantage. Firstly, a model with a new approach for taking damping effects into account is derived based on the electrical transmission line theory. By comparison with the old model, the new approach is validated, and occurring differences are discussed. Moreover, a numerical application with the consideration of damping is implemented for confirmation. The influence of the rear sound strength on the feedback-path system is investigated, and the optimal condition is determined. Finally, it is proven that the proposed source has an advantage of an extended phase lag and a time delay in the feedback-path system by both frequency-response analysis and numerical calculation of the time response.

  10. Stable sulfur and oxygen isotopes as geochemical tracers of sulfate in karst waters

    Science.gov (United States)

    Sun, Jing; Kobayashi, Tatsuaki; Strosnider, William H. J.; Wu, Pan

    2017-08-01

    Karst water resources, which are extremely sensitive to mining activities, are critical for the support of human societies and ecological systems in many regions worldwide. In order to determine the sources and fate of dissolved sulfate in low-pH karst waters, hydrochemical variations of karst waters with and without acid mine drainage (AMD) impacts were investigated along with stable isotope dynamics. As expected, hydrochemical characteristics and isotopic compositions of the AMD and AMD-downstream water (ADW) were dramatically different from that of the non-AMD-impacted water (NAW). The sources of sulfur isotopes in sulfate were predominantly pyrite oxidation for the AMD and ADW, and atmospheric deposition for the NAW. Based on the general isotope-balance model, the relative proportions of sulfate oxygen derived from water and air were calculated. The mean proportion of sulfate oxygen derived from water in ADW was roughly double that of AMD. This suggests that the sulfate associated with AMD is predominantly influenced by aerobic pyrite oxidation, while that of ADW is likely affected by the dissolution of pyrite under anaerobic conditions in reservoir sediment. This observation was coincident with the noted variations of hydrochemical characteristics and was supported by principal component analysis. These results provide a better understanding of how stable isotopes of sulfate and water can be used to track mining contamination in karst aquifers, which could benefit remediation planning for these distinctive systems.

  11. The Dammam aquifer in Bahrain - Hydrochemical characterization and alternatives for management of groundwater quality

    Science.gov (United States)

    Zubari, Waleed K.

    Over-ion of the Dammam aquifer, the principal aquifer in Bahrain, by the agricultural and domestic sectors, has led to its salinization by adjacent brackish and saline water bodies. A hydrochemical study identified the locations of the sources of aquifer salinization and delineated their areas of influence. The investigation indicates that the aquifer water quality is significantly modified as groundwater flows from the northwestern parts of Bahrain, where the aquifer receives its water by lateral underflow from eastern Saudi Arabia, to the southern and southeastern parts. Four types of salinization of the aquifer are identified: brackish-water up-flow from the underlying brackish-water zones in north-central, western, and eastern regions; seawater intrusion in the eastern region; intrusion of sabkha water in the southwestern region; and irrigation return flow in a local area in the western region. Four alternatives for the management of groundwater quality that are available to the water authorities in Bahrain are discussed and their priority areas are proposed, based on the type and extent of each salinization source, in addition to groundwater use in that area. The effectiveness of the proposed management options in controlling the degradation of water quality in the Dammam aquifer should be evaluated using simulation modeling. Résumé La surexploitation de l'aquifère de Damman, principal aquifère de Bahreïn, du fait des besoins agricoles et domestiques, a conduit à sa salinisation à partir d'eaux voisines saumâtres et salées. Une étude hydrochimique a identifié les origines de la salinisation de l'aquifère et a délimité leurs zones d'influence. Les recherches montrent que la qualité de l'eau souterraine est modifiée de façon significative pour les écoulements souterrains dirigés vers les secteurs sud et sud-est et provenant de la région nord-ouest de Bahreïn, là où l'aquifère est alimenté latéralement à partir de l'Arabie Saoudite

  12. LQG/LTR optimal attitude control of small flexible spacecraft using free-free boundary conditions

    Science.gov (United States)

    Fulton, Joseph M.

    Due to the volume and power limitations of a small satellite, careful consideration must be taken while designing an attitude control system for 3-axis stabilization. Placing redundancy in the system proves difficult and utilizing power hungry, high accuracy, active actuators is not a viable option. Thus, it is customary to find dependable, passive actuators used in conjunction with small scale active control components. This document describes the application of Elastic Memory Composite materials in the construction of a flexible spacecraft appendage, such as a gravity gradient boom. Assumed modes methods are used with Finite Element Modeling information to obtain the equations of motion for the system while assuming free-free boundary conditions. A discussion is provided to illustrate how cantilever mode shapes are not always the best assumption when modeling small flexible spacecraft. A key point of interest is first resonant modes may be needed in the system design plant in spite of these modes being greater than one order of magnitude in frequency when compared to the crossover frequency of the controller. LQG/LTR optimal control techniques are implemented to compute attitude control gains while controller robustness considerations determine appropriate reduced order controllers and which flexible modes to include in the design model. Key satellite designer concerns in the areas of computer processor sizing, material uncertainty impacts on the system model, and system performance variations resulting from appendage length modifications are addressed.

  13. An adaptive neuro fuzzy inference system controlled space cector pulse width modulation based HVDC light transmission system under AC fault conditions

    Science.gov (United States)

    Ajay Kumar, M.; Srikanth, N. V.

    2014-03-01

    In HVDC Light transmission systems, converter control is one of the major fields of present day research works. In this paper, fuzzy logic controller is utilized for controlling both the converters of the space vector pulse width modulation (SVPWM) based HVDC Light transmission systems. Due to its complexity in the rule base formation, an intelligent controller known as adaptive neuro fuzzy inference system (ANFIS) controller is also introduced in this paper. The proposed ANFIS controller changes the PI gains automatically for different operating conditions. A hybrid learning method which combines and exploits the best features of both the back propagation algorithm and least square estimation method is used to train the 5-layer ANFIS controller. The performance of the proposed ANFIS controller is compared and validated with the fuzzy logic controller and also with the fixed gain conventional PI controller. The simulations are carried out in the MATLAB/SIMULINK environment. The results reveal that the proposed ANFIS controller is reducing power fluctuations at both the converters. It also improves the dynamic performance of the test power system effectively when tested for various ac fault conditions.

  14. Controlled release of volatiles under mild reaction conditions: from nature to everyday products.

    Science.gov (United States)

    Herrmann, Andreas

    2007-01-01

    Volatile organic compounds serve in nature as semiochemicals for communication between species, and are often used as flavors and fragrances in our everyday life. The quite limited longevity of olfactive perception has led to the development of pro-perfumes or pro-fragrances--ideally nonvolatile and odorless fragrance precursors which release the active volatiles by bond cleavage. Only a limited amount of reaction conditions, such as hydrolysis, temperature changes, as well as the action of light, oxygen, enzymes, or microorganisms, can be used to liberate the many different chemical functionalities. This Review describes the controlled chemical release of fragrances and discusses additional challenges such as precursor stability during product storage as well as some aspects concerning toxicity and biodegradability. As the same systems can be applied in different areas of research, the scope of this Review covers fragrance delivery as well as the controlled release of volatiles in general.

  15. Some problems of control of dynamical conditions of technological vibrating machines

    Science.gov (United States)

    Kuznetsov, N. K.; Lapshin, V. L.; Eliseev, A. V.

    2017-10-01

    The possibility of control of dynamical condition of the shakers that are designed for vibration treatment of parts interacting with granular media is discussed. The aim of this article is to develop the methodological basis of technology of creation of mathematical models of shake tables and the development of principles of formation of vibrational fields, estimation of their parameters and control of the structure vibration fields. Approaches to build mathematical models that take into account unilateral constraints, the relationships between elements, with the vibrating surface are developed. Methods intended to construct mathematical model of linear mechanical oscillation systems are used. Small oscillations about the position of static equilibrium are performed. The original method of correction of vibration fields by introduction of the oscillating system additional ties to the structure are proposed. Additional ties are implemented in the form of a mass-inertial device for changing the inertial parameters of the working body of the vibration table by moving the mass-inertial elements. The concept of monitoring the dynamic state of the vibration table based on the original measuring devices is proposed. Estimation for possible changes in dynamic properties is produced. The article is of interest for specialists in the field of creation of vibration technology machines and equipment.

  16. Tai Chi for Chronic Pain Conditions: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Kong, Ling Jun; Lauche, Romy; Klose, Petra; Bu, Jiang Hui; Yang, Xiao Cun; Guo, Chao Qing; Dobos, Gustav; Cheng, Ying Wu

    2016-04-29

    Several studies reported that Tai Chi showed potential effects for chronic pain, but its role remains controversial. This review assessed the evidence regarding the effects of Tai Chi for chronic pain conditions. 18 randomized controlled trials were included in our review. The aggregated results have indicated that Tai Chi showed positive evidence on immediate relief of chronic pain from osteoarthritis (standardized mean difference [SMD], -0.54; 95% confidence intervals [CI], -0.77 to -0.30; P chronic pain from low back pain (SMD, -0.81; 95% CI, -1.11 to -0.52; P complementary and alternative medicine for chronic pain conditions.

  17. Responses to tonic heat pain in the ongoing EEG under conditions of controlled attention.

    Science.gov (United States)

    Giehl, Janet; Meyer-Brandis, Gesa; Kunz, Miriam; Lautenbacher, Stefan

    2014-03-01

    To confirm the existence of an ongoing electroencephalogram (EEG) pattern that is truly suggestive of pain, tonic heat pain was induced by small heat pulses at 1 °C above the pain threshold and compared to slightly less intense tonic non-painful heat pulses at 1 °C below the pain threshold. Twenty healthy subjects rated the sensation intensity during thermal stimulation. Possible confounding effects of attention were thoroughly controlled for by testing in four conditions: (1) focus of attention directed ipsilateral or (2) contralateral to the side of the stimulation, (3) control without a side preference, and (4) no control of attention at all. EEG was recorded via eight leads according to the 10/20 convention. Absolute power was computed for the frequency bands delta (0.5-4 Hz), theta (4-8 Hz), alpha1 (8-11 Hz), alpha2 (11-14 Hz), beta1 (14-25 Hz), and beta2 (25-35 Hz). Ratings were clearly distinct between the heat and pain conditions and suggestive for heat and pain sensations. Manipulation of attention proved to be successful by producing effects on the ratings and on the EEG activity (with lower ratings and lower EEG activity (theta, beta1, 2) over central areas for side-focused attention). During pain stimulation, lower central alpha1 and alpha2 activity and higher right-parietal and right-occipital delta power were observed compared to heat stimulation. This EEG pattern was not influenced by the manipulation of attention. Since the two types of stimuli (pain, heat) were subjectively felt differently although stimulation intensities were nearby, we conclude that this EEG pattern is clearly suggestive of pain.

  18. Condition-based Human Reliability Assessment for digitalized control room

    International Nuclear Information System (INIS)

    Kang, H. G.; Jang, S. C.; Eom, H. S.; Ha, J. J.

    2005-04-01

    In safety-critical systems, the generation failure of an actuation signal is caused by the concurrent failures of the automated systems and an operator action. These two sources of safety signals are complicatedly correlated. The failures of sensors or automated systems will cause a lack of necessary information for a human operator and result in error-forcing contexts such as the loss of corresponding alarms and indications. In the conventional analysis, the Human Error Probabilities (HEP) are estimated based on the assumption of 'normal condition of indications and alarms'. In order to construct a more realistic signal-generation failure model, we have to consider more complicated conditions in a more realistic manner. In this study, we performed two kinds of investigation for addressing this issue. We performed the analytic calculations for estimating the effect of sensors failures on the system unavailability and plant risk. For the single-parameter safety signals, the analysis result reveals that the quantification of the HEP should be performed by focusing on the 'no alarm from the automatic system and corresponding indications unavailable' situation. This study also proposes a Condition-Based Human Reliability Assessment (CBHRA) method in order to address these complicated conditions in a practical way. We apply the CBHRA method to the manual actuation of the safety features such as a reactor trip and auxiliary feedwater actuation in Korean Standard Nuclear Power Plants. In the case of conventional single HEP method, it is very hard to consider the multiple HE conditions. The merit of CBHRA is clearly shown in the application to the AFAS generation where no dominating HE condition exits. In this case, even if the HE conditions are carefully investigated, the single HEP method cannot accommodate the multiple conditions in a fault tree. On the other hand, the application result of the reactor trip in SLOCA shows that if there is a dominating condition, the use

  19. Robust Control of an Ill-Conditioned Aircraft

    DEFF Research Database (Denmark)

    Breslin, S.G.; Tøffner-Clausen, S.; Grimble, M.J.

    1996-01-01

    A robust controller is designed for a linear model of an Advanced Short Take-Off and Vertical Landing (ASTOVL) aircraft at one operating point.......A robust controller is designed for a linear model of an Advanced Short Take-Off and Vertical Landing (ASTOVL) aircraft at one operating point....

  20. A comparison of Reactivity Controlled Compression Ignition (RCCI) and Gasoline Compression Ignition (GCI) strategies at high load, low speed conditions

    International Nuclear Information System (INIS)

    Kavuri, Chaitanya; Paz, Jordan; Kokjohn, Sage L.

    2016-01-01

    Highlights: • Targeting high load-low speed, optimizations of RCCI and GCI strategies were performed. • The two strategies were compared in terms of performance, controllability and stability. • The optimum cases had high gross indicated efficiency (∼47%) and low NOx emissions. • RCCI strategy showed better combustion control but had higher soot emissions. • GCI strategy was relatively more sensitive to fluctuations in charge conditions. - Abstract: Past research has shown that Reactivity Controlled Compression Ignition (RCCI) and Gasoline Compression Ignition (GCI) combustion are promising approaches to improve efficiency and reduce pollutant emissions. However, the benefits have generally been confined to mid-load operating conditions. To enable practical application, these approaches must be able to operate over the entire engine map. A particularly challenging area is high load, low speed operation. Accordingly, the present work uses detailed CFD modeling and engine experiments to compare RCCI and GCI combustion strategies at a high load, low speed condition. Computational optimizations of RCCI and GCI combustion were performed at 20 bar gross indicated mean effective pressure (IMEP) and 1300 rev/min. The optimum points from the two combustion strategies were verified using engine experiments and were used to make the comparisons between RCCI and GCI combustion. The comparison showed that both the strategies had very similar combustion characteristics with a near top dead center injection initiating combustion. A parametric study was performed to identify the key input parameters that control combustion for the RCCI and GCI strategies. For both strategies, the combustion phasing could be controlled by the start of injection (SOI) timing of the near TDC injection. The short ignition delay of diesel fuel gave the RCCI strategy better control over combustion than the GCI strategy, but also had a simultaneous tradeoff with soot emissions. With the GCI

  1. INCREASING FISH PRODUCTIVITY OF POND ECOSYSTEMS BY FERTILIZING THEM WITH DISTILLER'S GRAINS

    Directory of Open Access Journals (Sweden)

    N. Tson’

    2015-03-01

    Full Text Available Purpose. To study fish culture parameters of young-of-the-year carp in the conditions of industrial fish-growing ponds when applying experimental repeated fertilization with distiller’s grain. Methodology. The study was conducted in industrial fish-growing ponds. The wastes of alcohol industry – the distiller’s grain as organic fertilizer was gradually introduced into ponds at following amounts: first application – 1,0 t/ha, second application in 10 days – 0,5 t/ha, third application in 12 days – 0,5 t/ha. The control ponds were fertilized with humus (2 t/ha. Young-of-the-year carp (Cyprinus carpio were grown in monoculture at stocking density of 30 000 fish/ha. In addition, 100 kg/ha of lime were applied during the culture season in the experiment and control. Fertilization with humus and application of lime in ponds, hydrochemical studies, sampling and processing of hydrobiological samples, fish culturing and statistical studies were carried out according to standard methods. Findings. Gradual fertilizing with distiller’s grain (to the total 2 t/ha gave the possibility to create favorable hydrochemical and hydrobiological regimes. An average daily growth in the experimental fish groups of 0,44 ± 0,09 g/day that was similar to in the control (0,45 ± 0,11 g/day with positive significant correlation between them (r = 0,97; p <0,001 was achieved. The performed measures gave a possibility to obtain fish productivity in the experimental variant 10.7% more than in the control. An economic effect of 14.3% cost reduction for fertilizing ponds was achieved. Originality. For the first time we presented the results of fish culture and biological parameters of young-of-the-year carp in industrial ponds when applying 3-time fertilization with distiller’s grain. Practical Value. The obtained results are the basis for the broad use of non-traditional organic fertilizer – distiller’s grain in industrial ponds, when growing young

  2. Second-order Optimality Conditions for Optimal Control of the Primitive Equations of the Ocean with Periodic Inputs

    International Nuclear Information System (INIS)

    Tachim Medjo, T.

    2011-01-01

    We investigate in this article the Pontryagin's maximum principle for control problem associated with the primitive equations (PEs) of the ocean with periodic inputs. We also derive a second-order sufficient condition for optimality. This work is closely related to Wang (SIAM J. Control Optim. 41(2):583-606, 2002) and He (Acta Math. Sci. Ser. B Engl. Ed. 26(4):729-734, 2006), in which the authors proved similar results for the three-dimensional Navier-Stokes (NS) systems.

  3. An interactive health communication application for supporting parents managing childhood long-term conditions: outcomes of a randomized controlled feasibility trial.

    Science.gov (United States)

    Swallow, Veronica M; Knafl, Kathleen; Santacroce, Sheila; Campbell, Malcolm; Hall, Andrew G; Smith, Trish; Carolan, Ian

    2014-12-03

    Families living with chronic or long-term conditions such as chronic kidney disease (CKD), stages 3-5, face multiple challenges and respond to these challenges in various ways. Some families adapt well while others struggle, and family response to a condition is closely related to outcome. With families and professionals, we developed a novel condition-specific interactive health communication app to improve parents' management ability-the online parent information and support (OPIS) program. OPIS consists of a comprehensive mix of clinical caregiving and psychosocial information and support. The purpose of this study was to (1) assess feasibility of a future full-scale randomized controlled trial (RCT) of OPIS in terms of recruitment and retention, data collection procedures, and psychometric performance of the study measures in the target population, and (2) investigate trends in change in outcome measures in a small-scale RCT in parents of children with CKD stages 3-5. Parents were recruited from a pediatric nephrology clinic and randomly assigned to one of two treatment groups: usual support for home-based clinical caregiving (control) or usual support plus password-protected access to OPIS for 20 weeks (intervention). Both groups completed study measures at study entry and exit. We assessed feasibility descriptively in terms of recruitment and retention rates overall; assessed recruitment, retention, and uptake of the intervention between groups; and compared family condition management, empowerment to deliver care, and fathers' involvement between groups. We recruited 55 parents of 39 children (42% of eligible families). Of those, about three-quarters of intervention group parents (19/26, 73%) and control group parents (22/29, 76%) were retained through completion of 20-week data collection. The overall retention rate was 41/55 (75%). The 41 parents completing the trial were asked to respond to the same 10 questionnaire scales at both baseline and 20 weeks

  4. Nitrate pollution of groundwater; all right…, but nothing else?

    International Nuclear Information System (INIS)

    Menció, Anna; Mas-Pla, Josep; Otero, Neus; Regàs, Oriol; Boy-Roura, Mercè

    2016-01-01

    Contamination from agricultural sources and, in particular, nitrate pollution, is one of the main concerns in groundwater management. However, this type of pollution entails the entrance of other substances into the aquifer, as well as it may promote other processes. In this study, we deal with hydrochemical and isotopic analysis of groundwater samples from four distinct zones in Catalonia (NE Spain), which include 5 different aquifer types, to investigate the influence of fertilization on the overall hydrochemical composition of groundwater. Results indicate that intense fertilizer application, causing high nitrate pollution in aquifers, also homogenize the contents of the major dissolved ions (i.e.; Cl - , SO 4 2- , Ca 2+ , Na + , K + , and Mg 2+ ). Thus, when groundwater in igneous and sedimentary aquifers is compared, significant differences are observed under natural conditions for Cl - , Na + and Ca 2+ (with p-values ranging from < 0.001 to 0.038), and when high nitrate concentrations occur, these differences are reduced (most p-values ranged between 0.054 and 0.978). Moreover, positive linear relationships between nitrate and some ions are found indicating the magnitude of the fertilization impact on groundwater hydrochemistry (with R 2 values of 0.490, 0.609 and 0.470, for SO 4 2- , Ca 2+ and Cl - , respectively). Nevertheless, the increasing concentration of specific ions is not only attributed to agricultural pollution, but to their enhancing effect upon the biogeochemical processes that control water-rock interactions. Such results raise awareness that these processes should be evaluated in advance in order to assess an adequate groundwater resources management. - Highlights: • The effects of nitrate pollution have been evaluated in five different aquifer types • Statistical and multivariate analyses are used to identify groundwater changes • Agricultural pollution modifies groundwater conditions and geochemical processes • Manure application

  5. Generation of synthetic surface electromyography signals under fatigue conditions for varying force inputs using feedback control algorithm.

    Science.gov (United States)

    Venugopal, G; Deepak, P; Ghosh, Diptasree M; Ramakrishnan, S

    2017-11-01

    Surface electromyography is a non-invasive technique used for recording the electrical activity of neuromuscular systems. These signals are random, complex and multi-component. There are several techniques to extract information about the force exerted by muscles during any activity. This work attempts to generate surface electromyography signals for various magnitudes of force under isometric non-fatigue and fatigue conditions using a feedback model. The model is based on existing current distribution, volume conductor relations, the feedback control algorithm for rate coding and generation of firing pattern. The result shows that synthetic surface electromyography signals are highly complex in both non-fatigue and fatigue conditions. Furthermore, surface electromyography signals have higher amplitude and lower frequency under fatigue condition. This model can be used to study the influence of various signal parameters under fatigue and non-fatigue conditions.

  6. Evaluation of groundwater quality and assessment of scaling potential and corrosiveness of water samples in Kadkan aquifer, Khorasan-e-Razavi Province, Iran.

    Science.gov (United States)

    Esmaeili-Vardanjani, Mostafa; Rasa, Iraj; Amiri, Vahab; Yazdi, Mohammad; Pazand, Kaveh

    2015-02-01

    The chemical analysis of 129 groundwater samples in the Kadkan area, Khorasan-e-Razavi Province, NE of Iran was evaluated to determine the hydrochemical processes, assessment of groundwater quality for irrigation purposes, corrosiveness, and scaling potential of the groundwater. Accordingly, the suitability of groundwater for irrigation was evaluated based on the sodium adsorption ratio, residual sodium carbonate, sodium percent, salinity hazard, and US Salinity Laboratory hazard diagram. Based on the electrical conductivity and sodium adsorption ratio, the dominant classes are C3-S1, C3-S2, C2-S1, and C4-S2. According to the Wilcox plot, about 50 % of the samples fall in the "Excellent to Good" and "Good to Permissible" classes. Besides, the Langelier saturation index, Ryznar stability index (RSI), Larson-Skold index, and Puckorius scaling index were evaluated for assessing the corrosiveness and scaling potential of the groundwater. Corrosiveness and scaling indices stated that the majority of samples are classified into "Aggressive" and "Very Aggressive" category. In addition, chloride and sulfate interfere in 90 % of the samples. Assessment of hydrochemical characteristics indicates Na-Mg-Cl as the predominant hydrochemical type. Spatial distribution of hydrochemical parameters indicates that hydrochemical processes are influenced by geology and hydrogeology of Kadkan aquifer. The Gibbs plots gave an indication that groundwater chemistry in this area may have acquired the chemistry mainly from evaporation and mineral precipitation. Grouping the samples based on Q-mode hierarchical cluster analysis helped to more separation of similar samples. The R-mode HCA grouped analyzed parameters into two groups based on similarity of hydrochemical characteristics. As a result, the samples collected in northern and southern parts of the study area show the best quality (i.e., lowest salinity) for some purposes such as irrigation and drinking.

  7. Forsmark site investigation. Hydrochemical monitoring of groundwaters and surface waters. Results from water sampling in the Forsmark area, January-December 2009

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ann-Chatrin (ed.); Berg, Cecilia; Harrstroem, Johan; Joensson, Stig; Thur, Pernilla (Geosigma AB (Sweden)); Borgiel, Micke; Qvarfordt, Susanne (Sveriges Vattenekologer AB (Sweden))

    2010-09-15

    The fifth year (2009) of hydrochemical monitoring of groundwaters, surface waters and precipitation in Forsmark is documented in the report. The hydrochemical monitoring programme 2009 included water sampling from: - percussion- and core boreholes equipped with installations for long-term pressure monitoring, tracer tests and water sampling in packed off borehole sections, sampling and analysis performed twice (spring and autumn), - near surface groundwaters (sampling four times a year), - private wells (once per year in October), - surface waters (eleven sampling occasions per year). Due to the somewhat different performance of the hydrogeochemical monitoring of the deep groundwaters during the autumn 2009 compared to previous years, some new findings and knowledge were obtained: 1) Removal of water volumes corresponding to three to five times the volume of the borehole section (the routine procedure) is seldom enough to obtain a complete exchange of the water present in the borehole section when the pumping starts. 2) It is likely that the elevated sulphide concentrations observed in the monitoring programme /1/ is due to contamination from initial water present in the borehole sections when the pumping starts. This water may have a very high sulphide concentration. Dirty water in tubes and in stand pipes may also contribute to the enhanced sulphide concentration. 3) Plug flow calculations will be introduced in the future as a new routine procedure to estimate the water volumes to be removed, in order to exchange the section water volume, prior to groundwater sampling in delimited borehole sections. During the autumn sampling, sample series of five samples per sampling location were collected during continuous pumping in thirteen selected borehole sections. Furthermore, special efforts were put on cleaning of stand pipes and exchange of water prior to sampling. The analytical protocol was rather extensive and included sulphide and uranium analyses for each sample

  8. Forsmark site investigation. Hydrochemical monitoring of groundwaters and surface waters. Results from water sampling in the Forsmark area, January-December 2009

    International Nuclear Information System (INIS)

    Nilsson, Ann-Chatrin; Borgiel, Micke; Qvarfordt, Susanne

    2010-09-01

    The fifth year (2009) of hydrochemical monitoring of groundwaters, surface waters and precipitation in Forsmark is documented in the report. The hydrochemical monitoring programme 2009 included water sampling from: - percussion- and core boreholes equipped with installations for long-term pressure monitoring, tracer tests and water sampling in packed off borehole sections, sampling and analysis performed twice (spring and autumn), - near surface groundwaters (sampling four times a year), - private wells (once per year in October), - surface waters (eleven sampling occasions per year). Due to the somewhat different performance of the hydrogeochemical monitoring of the deep groundwaters during the autumn 2009 compared to previous years, some new findings and knowledge were obtained: 1) Removal of water volumes corresponding to three to five times the volume of the borehole section (the routine procedure) is seldom enough to obtain a complete exchange of the water present in the borehole section when the pumping starts. 2) It is likely that the elevated sulphide concentrations observed in the monitoring programme /1/ is due to contamination from initial water present in the borehole sections when the pumping starts. This water may have a very high sulphide concentration. Dirty water in tubes and in stand pipes may also contribute to the enhanced sulphide concentration. 3) Plug flow calculations will be introduced in the future as a new routine procedure to estimate the water volumes to be removed, in order to exchange the section water volume, prior to groundwater sampling in delimited borehole sections. During the autumn sampling, sample series of five samples per sampling location were collected during continuous pumping in thirteen selected borehole sections. Furthermore, special efforts were put on cleaning of stand pipes and exchange of water prior to sampling. The analytical protocol was rather extensive and included sulphide and uranium analyses for each sample

  9. The link between antioxidant enzymes catalase and glutathione S-transferase and physiological condition of a control population of terrestrial isopod (Porcellio scaber).

    Science.gov (United States)

    Jemec, Anita; Lešer, Vladka; Drobne, Damjana

    2012-05-01

    The aim of this work was to investigate if the activities of catalase and glutathione S-transferase in a control population of terrestrial isopods (Porcellio scaber) are correlated with the physiological condition of the isopods. For this purpose, the activities of these enzymes were analysed in isopods from a stock population and in parallel, the physiological condition of the same specimens was assessed using a histological approach based on epithelial thickness and lipid droplets. We found a correlation between antioxidant enzymes and the physiological condition of the isopods. This implies that these enzymes could be used as predictive indicators of the physiological condition in a stock population before comprehensive toxicological studies are conducted and also in control group after the experiment. When a control group is found to be very heterogeneous in terms of physiological condition, the experiment should be repeated with a larger number of experimental animals. The findings of this study will contribute to more accurate experimental design of toxicity tests when using biomarkers. This should encourage other researchers to increase their effort to know the physiological state of their test organisms. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Controlled growth of CNT in mesoporous AAO through optimized conditions for membrane preparation and CVD operation

    Energy Technology Data Exchange (ETDEWEB)

    Ciambelli, P; Sarno, M; Leone, C; Sannino, D [Department of Chemical and Food Engineering, University of Salerno, I-84084 Fisciano (Italy); Arurault, L; Fontorbes, S; Datas, L; Lenormand, P; Le Blond Du Plouy, S, E-mail: msarno@unisa.it, E-mail: arurault@chimie.ups-tlse.fr [Universite de Toulouse, CIRIMAT, UPS/INPT/CNRS, LCMIE, F-31062 Toulouse Cedex 9 (France)

    2011-07-01

    Anodic aluminium oxide (RAAO) membranes with a mesoporous structure were prepared under strictly controlling experimental process conditions, and physically and chemically characterized by a wide range of experimental techniques. Commercial anodic aluminium oxide (CAAO) membranes were also investigated for comparison. We demonstrated that RAAO membranes have lower content of both water and phosphorus and showed better porosity shape than CAAO. The RAAO membranes were used for template growth of carbon nanotubes (CNT) inside its pores by ethylene chemical vapour deposition (CVD) in the absence of a catalyst. A composite material, containing one nanotube for each channel, having the same length as the membrane thickness and an external diameter close to the diameter of the membrane holes, was obtained. Yield, selectivity and quality of CNTs in terms of diameter, length and arrangement (i.e. number of tubes for each channel) were optimized by investigating the effect of changing the experimental conditions for the CVD process. We showed that upon thermal treatment RAAO membranes were made up of crystallized allotropic alumina phases, which govern the subsequent CNT growth, because of their catalytic activity, likely due to their Lewis acidity. The strict control of experimental conditions for membrane preparation and CNT growth allowed us to enhance the carbon structural order, which is a critical requisite for CNT application as a substitute for copper in novel nano-interconnects.

  11. An Improved Current Controller to ensure the robust performance of grid-connected converters under weak grid conditions

    DEFF Research Database (Denmark)

    Khazraj, Hesam; Silva, Filipe Miguel Faria da; Bak, Claus Leth

    2016-01-01

    Voltage Source Converters (VSCs) operating in very weak grids with low Short Circuit Ratio (SCR) are known to meet stability challenges. This article investigates instability of a grid connected current-controlled converter under weak grid conditions, which is often attributed to the dynamic...

  12. A Closed-Loop Control Strategy for Air Conditioning Loads to Participate in Demand Response

    Directory of Open Access Journals (Sweden)

    Xiaoqing Hu

    2015-08-01

    Full Text Available Thermostatically controlled loads (TCLs, such as air conditioners (ACs, are important demand response resources—they have a certain heat storage capacity. A change in the operating status of an air conditioner in a small range will not noticeably affect the users’ comfort level. Load control of TCLs is considered to be equivalent to a power plant of the same capacity in effect, and it can significantly reduce the system pressure to peak load shift. The thermodynamic model of air conditioning can be used to study the aggregate power of a number of ACs that respond to the step signal of a temperature set point. This paper analyzes the influence of the parameters of each AC in the group to the indoor temperature and the total load, and derives a simplified control model based on the two order linear time invariant transfer function. Then, the stability of the model and designs its Proportional-Integral-Differential (PID controller based on the particle swarm optimization (PSO algorithm is also studied. The case study presented in this paper simulates both scenarios of constant ambient temperature and changing ambient temperature to verify the proposed transfer function model and control strategy can closely track the reference peak load shifting curves. The study also demonstrates minimal changes in the indoor temperature and the users’ comfort level.

  13. Artificial Post mining lakes - a challenge for the integration in natural hydrography and river basin management

    Science.gov (United States)

    Fleischhammel, Petra; Schoenheinz, Dagmar; Grünewald, Uwe

    2010-05-01

    mesotrophic conditions. The aquatic flora and fauna are limited to a few well adapted species. Therefore, the issue of hydrochemical constitution of the lakes' waters becomes more and more relevant. The prediction of water quality development in post mining lakes is a key requirement to regulate and manage the later hydrochemical conditions. Initially, this prediction was made by individual case studies for single lakes. By means of an iterative research process during the last years, hydrochemical lake models were developed as prediction tools, which allow a complex processing of interconnected post mining lakes and their integration in natural hydrography with respect to quantitative and qualitative evaluation. To counteract the poor water quality of mining lakes, flooding by surface water from neighbouring river basins, e.g. the river Neisse, shall support a quicker and thereby hydrochemically less damaging lake filling. However, this external flooding is only feasible under conditions of high runoff and therefore only as intermitted practice applicable. Additionally, technological measures of water treatment have to be applied to achieve the required effluent quality and to ensure the designated use. Regrettably, these technologies aren't commercially standard up to now and are not sustainable, while flooding or provides a huge amount itself of positive potential for hydrochemical stabilization. The river basin management of the rivers Spree and Schwarze Elster is attended by a common working group of the Federal States of Brandenburg and Berlin as well as the Free State of Saxony. The quantitative distribution of the regionally available water considers the potential use for drinking water supply, process water, …, and the flooding of open-pits. However, due to the formulated rank order, the flooding of the numerous mining open pits in Lusatia is on the last position. To guarantee a reliable flooding and a continuous water supply of the post mining lakes, additional

  14. A study of a two stage maximum power point tracking control of a photovoltaic system under partially shaded insolation conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Kenji; Takano, Ichiro; Sawada, Yoshio [Kogakuin University, Tokyo 163-8677 (Japan)

    2006-11-23

    A photovoltaic (PV) array shows relatively low output power density, and has a greatly drooping current-voltage (I-V) characteristic. Therefore, maximum power point tracking (MPPT) control is used to maximize the output power of the PV array. Many papers have been reported in relation to MPPT. However, the current-power (I-P) curve sometimes shows multi-local maximum point mode under non-uniform insolation conditions. The operating point of the PV system tends to converge to a local maximum output point which is not the real maximal output point on the I-P curve. Some papers have been also reported, trying to avoid this difficulty. However, most of those control systems become rather complicated. Then, the two stage MPPT control method is proposed in this paper to realize a relatively simple control system which can track the real maximum power point even under non-uniform insolation conditions. The feasibility of this control concept is confirmed for steady insolation as well as for rapidly changing insolation by simulation study using software PSIM and LabVIEW. (author)

  15. A Study of a Two Stage Maximum Power Point Tracking Control of a Photovoltaic System under Partially Shaded Insolation Conditions

    Science.gov (United States)

    Kobayashi, Kenji; Takano, Ichiro; Sawada, Yoshio

    A photovoltaic array shows relatively low output power density, and has a greatly drooping Current-Voltage (I-V) characteristic. Therefore, Maximum Power Point Tracking (MPPT) control is used to maximize the output power of the array. Many papers have been reported in relation to MPPT. However, the Current-Power (I-P) curve sometimes shows multi-local maximum points mode under non-uniform insolation conditions. The operating point of the PV system tends to converge to a local maximum output point which is not the real maximal output point on the I-P curve. Some papers have been also reported, trying to avoid this difficulty. However most of those control systems become rather complicated. Then, the two stage MPPT control method is proposed in this paper to realize a relatively simple control system which can track the real maximum power point even under non-uniform insolation conditions. The feasibility of this control concept is confirmed for steady insolation as well as for rapidly changing insolation by simulation study using software PSIM and LabVIEW. In addition, simulated experiment confirms fundament al operation of the two stage MPPT control.

  16. Distributed computation of supremal conditionally-controllable sublanguages

    Czech Academy of Sciences Publication Activity Database

    Komenda, Jan; Masopust, Tomáš

    2016-01-01

    Roč. 89, č. 2 (2016), s. 424-436 ISSN 0020-7179 R&D Projects: GA ČR GA15-02532S; GA MŠk LH13012 Institutional support: RVO:67985840 Keywords : discrete-event systems * supervisory control * coordination control Subject RIV: BA - General Mathematics Impact factor: 2.208, year: 2016 http://www.tandfonline.com/doi/full/10.1080/00207179.2015.1079736

  17. Use of electrical tomography methods to determinate the extension and main migration routes of uncontrolled landfill leachates in fractured areas

    Energy Technology Data Exchange (ETDEWEB)

    Casado, Ismael, E-mail: iscaferr@gmail.com [Department of Petrology, Geochemistry and Geological Prospectio, Universitat de Barcelona, Martí i Franquès s/n, 08030 Barcelona (Spain); Department of Geology and Environmental Earth Science, Miami University, 501 East High Street, 45056 Oxford, OH (United States); Mahjoub, Himi [Department of Petrology, Geochemistry and Geological Prospectio, Universitat de Barcelona, Martí i Franquès s/n, 08030 Barcelona (Spain); Ecole Nationale des Sciences Appliquées d' Al Hoceima (ENSAH), University Mohammed Premier, Ajdir, Al Hoceima (Morocco); Lovera, Raul [Department of Petrology, Geochemistry and Geological Prospectio, Universitat de Barcelona, Martí i Franquès s/n, 08030 Barcelona (Spain); Fernández, Jesús, E-mail: jfernandezc@aragon.es [Department of Agriculture, Ranching and Environment, Diputación General de Aragon (DGA), Plaza de San Pedro Nolasco, 7, 50071 Zaragoza (Spain); Casas, Albert [Department of Petrology, Geochemistry and Geological Prospectio, Universitat de Barcelona, Martí i Franquès s/n, 08030 Barcelona (Spain)

    2015-02-15

    This study focuses on the uses of the electrical tomography and its relationship with hydrochemical data in order to characterize contaminated groundwater flows in fractured aquifers. The studied area is contaminated with different hazardous substances like lyndanes, organochlorinated compounds and benzenes coming from the old non-controlled Sardas landfill. The enormous volumes of wastes filling the landfill have generated a convoluted mixture of leachates. Due to the lack of a landfill liner, the leachates have migrated through the fractured Eocene marls towards the Gallego River. The striking correlation between high concentrations of polluted groundwater and low electrical resistivity of the subsurface (< 8 Ω·m) allows defining the principal contaminant migration route thanks to the distribution of these conductive anomalies. This mapping verifies that there is intense tectonical–structural control of the leachate migration, because the deep migration presents the same direction as the geological axis fold. - Highlights: • The outcrop topographic reconstruction is done using cores and aerial photographs. • Hydrochemical and geophysical data allow defining two leachate migration paths. • Conductive anomalies in ERT are linked to high contaminant concentration. • The distribution of conductive anomalies defines the fractured basement migration. • The plume direction reflects important tectonic control in the migration process.

  18. Control of Greenhouse Environmental Conditions with IOT Based Monitoring and Analysis System

    Directory of Open Access Journals (Sweden)

    Ali Çaylı

    2017-10-01

    Full Text Available Wireless sensor networks applications and inter-machine communication (M2M, called the Internet of Things, help decision-makers to control complex systems thanks to the low data-rate and cost-effective data collection and analysis. These technologies offer new possibilities to monitor environmental management and agricultural policies, and to improve agricultural production, especially in low-income rural areas. In this study, IoT is proposed with a low cost, flexible and scalable data collection and analysis system. For this purpose, open source hardware microprocessor cards and sensors are stored in the greenhouse computer database using the IEEE 802.15.4 Zigbee wireless communication protocol. The data can be analyzed by greenhouse computer analysis software, which is developed with the PHP programming language. It is possible to monitor the real time data from the greenhouse computer. Also alert rules definitions can be made and the system was tested in greenhouse conditions. It has been observed that it performs operations steadily such as data transfer, sensor measurements and data processing. The proposed system may be useful for monitoring indoor climate and controlling ventilation, irrigation and heating systems, especially for small enterprises due to the modular structure.

  19. Evaluative conditioning of food technologies

    DEFF Research Database (Denmark)

    Loebnitz, Natascha; Grunert, Klaus G

    2015-01-01

    Consumer attitudes play an important role in the acceptance of new technologies. The success of food innovations depends on understanding how consumers form and change attitudes toward food technologies. Earlier post hoc explanations suggest that evaluative conditioning can change consumer...... attitudes toward food technologies. The present study tests how evaluative conditioning can affect consumer acceptance of new food technologies. Furthermore, authors investigate whether evaluative conditioning is resistant to extinction after a two-month period and whether the evaluative conditioning effect...... prevails in a product-related context. Within an evaluative conditioning paradigm including between-subjects control groups in addition to standard within-subjects control conditions, participants were presented with three food technologies (conventional, enzyme, and genetic technology) paired...

  20. A robust predictive current controller for healthy and open-circuit faulty conditions of five-phase BLDC drives applicable for wind generators and electric vehicles

    International Nuclear Information System (INIS)

    Salehi Arashloo, Ramin; Salehifar, Mehdi; Romeral, Luis; Sala, Vicent

    2015-01-01

    Highlights: • Model predictive deadbeat control of generator stator phase currents. • Fault tolerant control of five-phase BLDC generator. • Control of stator phase currents under normal and open-circuit faulty conditions. • MATLAB simulation and experimental verification of proposed control method. • Verification of robustness and fast respond of proposed controlling method. - Abstract: Fault tolerant control of five-phase brushless direct current (BLDC) machines is gaining more importance in high-safety applications such as offshore wind generators and automotive industries. In many applications, traditional controllers (such as PI controllers) are used to control the stator currents under faulty conditions. These controllers have good performance with dc signals. However, in the case of missing one or two of the phases, appropriate reference currents of these machines have oscillatory dynamics both in phase- and synchronous-reference frames. Non-constant nature of these reference values requires the implication of fast current controllers. In this paper, model predictive deadbeat controllers are proposed to control the stator currents of five-phase BLDC machines under normal and faulty conditions. Open circuit fault is considered for both one and two stator phases, and the behaviour of proposed controlling method is evaluated. This evaluation is generally focused on first, sensitivity of proposed controlling method and second, its speed in following reference current values under transient states. Proposed method is simulated and is verified experimentally on a five-phase BLDC drive

  1. A Randomized Controlled Pilot Trial of Classroom-Based Mindfulness Meditation Compared to an Active Control Condition in 6th Grade Children

    Science.gov (United States)

    Britton, Willoughby B.; Lepp, Nathaniel E.; Niles, Halsey F.; Rocha, Tomas; Fisher, Nathan; Gold, Jonathan

    2014-01-01

    Children in the United States are at risk for numerous psychological problems, such as anxiety, attention problems, and mood disorders, and are underserved by current mental health provisions. The current study is a pilot trial to examine the effects of a nonelective, classroom-based, teacher-implemented, mindfulness meditation intervention on standard clinical measures of mental health and affect in middle school children. A total of 101 healthy sixth-grade students (55 boys and 46 girls) were randomized to either an Asian history course with daily mindfulness meditation practice (intervention group) or an African history course with a matched experiential activity (active control group). Self-reported data was collected by administering the Youth Self Report (YSR), a modified Spielberger State-Trait Anxiety Inventory, and the Cognitive and Affective Mindfulness Measure -Revised before and after 6 weeks of meditation or active control condition. Both meditators and active controls decreased significantly on the YSR Internalizing Problems, Externalizing Problems, and Attention Problems subscales but did not differ in the extent of their improvements. Both groups also showed comparable improvements on measures in affect. Meditators were significantly less likely to develop suicidal ideation or thoughts of self-harm than controls. Improvements in affect were correlated with increases in mindfulness in meditators but not controls. These results suggest that mindfulness training may yield both unique and nonspecific benefits that are shared by other novel activities. PMID:24930819

  2. A Novel Distributed Economic Model Predictive Control Approach for Building Air-Conditioning Systems in Microgrids

    Directory of Open Access Journals (Sweden)

    Xinan Zhang

    2018-04-01

    Full Text Available With the penetration of grid-connected renewable energy generation, microgrids are facing stability and power quality problems caused by renewable intermittency. To alleviate such problems, demand side management (DSM of responsive loads, such as building air-conditioning system (BACS, has been proposed and studied. In recent years, numerous control approaches have been published for proper management of single BACS. The majority of these approaches focus on either the control of BACS for attenuating power fluctuations in the grid or the operating cost minimization on behalf of the residents. These two control objectives are paramount for BACS control in microgrids and can be conflicting. As such, they should be considered together in control design. As individual buildings may have different owners/residents, it is natural to control different BACSs in an autonomous and self-interested manner to minimize the operational costs for the owners/residents. Unfortunately, such “selfish” operation can result in abrupt and large power fluctuations at the point of common coupling (PCC of the microgrid due to lack of coordination. Consequently, the original objective of mitigating power fluctuations generated by renewable intermittency cannot be achieved. To minimize the operating costs of individual BACSs and simultaneously ensure desirable overall power flow at PCC, this paper proposes a novel distributed control framework based on the dissipativity theory. The proposed method achieves the objective of renewable intermittency mitigation through proper coordination of distributed BACS controllers and is scalable and computationally efficient. Simulation studies are carried out to illustrate the efficacy of the proposed control framework.

  3. Controlled synthesis of quantum confined CsPbBr3 perovskite nanocrystals under ambient conditions

    Science.gov (United States)

    He, Huimei; Tang, Bing; Ma, Ying

    2018-02-01

    Room temperature recrystallization is a simple and convenient method for synthesis of all-inorganic perovskite nanomaterials with excellent luminescent properties. However, the fast crystallization usually brings the colloidal stability and uncontrollable synthesis issues in the formation of all-inorganic perovskite. In the present study, we present a new strategy to prepare the quantum confined CsPbBr3 nanocrystals with controlled morphology under ambient condition. With the assist of fatty acid-capped precursor, the crystallization and the following growth rate can be retarded. Thanks to the retarded reaction, the morphology can be varied from nanowires to nanoplates and the thickness can be controlled from 5-7 monolayers by simply adjusting the amount of octylammonium cations and oleic acid. The nanoplates exhibit a higher photoluminescence quantum yield than the nanowires possibly due to fewer defects in the nanoplates.

  4. Controlled Synthesis of Quantum Confined CsPbBr3 perovskite Nanocrystals under Ambient Condition.

    Science.gov (United States)

    He, Huimei; Tang, Bing; Ma, Ying

    2017-11-21

    Room temperature recrystallization is a simple and convenient method for synthesis of all-inorganic perovskite nanomaterials with excellent luminescent properties. However, the fast crystallization usually brings the colloidal stability and uncontrollable synthesis issues in the formation of all-inorganic perovskite. In the present study, we present a new strategy to prepare the quantum confined CsPbBr3 nanocrystals with controlled morphology under ambient condition. With the assist of fatty acid-capped precursor, the crystallization and the following growth rate can be retarded. Thanks to the retarded reaction, the morphology can be varied from nanowires to nanoplates and the thickness can be controlled from 5 to 7 monolayers by simply adjusting the amount of octylammonium cations and oleic acid. The nanoplates exhibit a higher photoluminescence quantum yield than the nanowires possibly due to fewer defects in the nanoplates. © 2017 IOP Publishing Ltd.

  5. Current physical activity improves balance control during sensory conflicting conditions in older adults.

    Science.gov (United States)

    Buatois, S; Gauchard, G C; Aubry, C; Benetos, A; Perrin, P

    2007-01-01

    Aging process is characterized by difficulties in ensuring balance control, especially in conditions of reduced or conflicting sensory information, leading to an increased risk of falling. Conversely, the practise of physical activities (PA) has been recognized as a good approach to improve the quality of balance control. This study aimed to investigate the influence of current and/or past PA on balance-related neurosensorial organization in older adults on the maintenance of the upright stance, especially during sensory conflicting situations. Postural control was evaluated by means of the Sensory Organization Test on 130 healthy noninstitutionalized volunteers aged over 65, split into four groups according to the presence or absence of PA before or after retirement. Subjects who practised PA for a long time (Gr1) and subjects who started PA after retirement (Gr2) displayed the best postural performances and better managed sensory conflicting situations compared to subjects who had stopped PA for many years (Gr3) and subjects who had never practised PA (Gr4). Multiple regression analyses revealed that current PA was the major determinant for postural parameters during sensorial conflict compared to age, gender, body mass index and past PA. Regular PA, even when started late in life, allows appropriate reorganization of the different components of postural control during sensory conflicting situations. Indeed, active subjects were more able to compensate for suppressed or perturbed sensory information by an increased usage of another referential and so to correct their posture by adopting a more appropriate balance strategy. Thus, PA counteracts the age-related decline of postural control and could consequently reduce the risk of falling.

  6. Determination of internal controls for quantitative gene expression of Isochrysis zhangjiangensis at nitrogen stress condition

    Science.gov (United States)

    Wu, Shuang; Zhou, Jiannan; Cao, Xupeng; Xue, Song

    2016-02-01

    Isochrysis zhangjiangensis is a potential marine microalga for biodiesel production, which accumulates lipid under nitrogen limitation conditions, but the mechanism on molecular level is veiled. Quantitative real-time polymerase chain reaction (qPCR) provides the possibility to investigate the gene expression levels, and a valid reference for data normalization is an essential prerequisite for firing up the analysis. In this study, five housekeeping genes, actin (ACT), α-tubulin (TUA), ß-tubulin (TUB), ubiquitin (UBI), 18S rRNA (18S) and one target gene, diacylglycerol acyltransferase (DGAT), were used for determining the reference. By analyzing the stabilities based on calculation of the stability index and on operating the two types of software, geNorm and bestkeeper, it showed that the reference genes widely used in higher plant and microalgae, such as UBI, TUA and 18S, were not the most stable ones in nitrogen-stressed I. zhangjiangensis, and thus are not suitable for exploring the mRNA expression levels under these experimental conditions. Our results show that ACT together with TUB is the most feasible internal control for investigating gene expression under nitrogen-stressed conditions. Our findings will contribute not only to future qPCR studies of I. zhangjiangensis, but also to verification of comparative transcriptomics studies of the microalgae under similar conditions.

  7. Control-limit preventive maintenance policies for components subject to imperfect preventive maintenance and variable operational conditions

    International Nuclear Information System (INIS)

    You Mingyi; Li Hongguang; Meng Guang

    2011-01-01

    This paper develops two component-level control-limit preventive maintenance (PM) policies for systems subject to the joint effect of partial recovery PM acts (imperfect PM acts) and variable operational conditions, and investigates the properties of the proposed policies. The extended proportional hazards model (EPHM) is used to model the system failure likelihood influenced by both factors. Several numerical experiments are conducted for policy property analysis, using real lifetime and operational condition data and typical characterization of imperfect PM acts and maintenance durations. The experimental results demonstrate the necessity of considering both factors when they do exist, characterize the joint effect of the two factors on the performance of an optimized PM policy, and explore the influence of the loading sequence of time-varying operational conditions on the performance of an optimized PM policy. The proposed policies extend the applicability of PM optimization techniques.

  8. The influence of managed versus natural hydrologic regimes on the hydrochemical patterns in a constructed wetland in the Athabasca oil sands region, Canada.

    Science.gov (United States)

    Biagi, K.; Oswald, C.; Nicholls, E.; Carey, S.

    2017-12-01

    Bitumen extraction via surface mining in the Athabasca Oil Sands Region (AOSR) results in permanent alteration of the landscape once rich in boreal forest and wetlands. As part of their legal requirements, oil companies must reclaim disturbed landscapes into functioning ecosystems, and to date only two pilot wetland-peatland systems have been constructed. Peatland reclamation is challenging as they must be completely reconstructed with few guidelines or previous work in this region. Furthermore, the variable sub-humid climate and salinity of waste-materials are obstacles to the success of peatland creation. In 2012, Syncrude Canada Ltd. constructed a 52 ha upland-wetland system, the Sandhill Fen Watershed (SFW), which was designed with a pump and underdrain system to provide freshwater and enhance drainage to limit salinization from underlying waste materials that have elevated electrical conductivity (EC) and Na+. The objective of this research is to understand the hydrochemical response of a constructed wetland to variations in hydrological management with respect to sources, flow pathways and major chemical transformations of water in the three years following commissioning. EC, major ions and stable isotopes were collected using a combination of high frequency and discrete water sampling from 2013-2015. Results indicate that high activity of both inflow and outflow pumps in 2013 kept the EC relatively low, with most wetland sites 1000 µS/cm in 2014 and >2000 µS/cm in 2015. Most wetland sites remained Ca+2 dominant where Ca+2 and Na+ averaged 200 and 130 mg/L, respectively. However, the most notable change in 2014 and 2015 was the emergence of several Na+ "hotspots" in the margins where Na+ concentrations averaged 450 mg/L while Ca+2 averaged 250 mg/L. Stable isotope data confirm that the "hotspots" match the underlying waste water and provide evidence of its upward transport and seepage under a natural hydrologic regime. Minimizing salinization is critical

  9. Study of two conditioning methods of parasitoids used in biological control prior to inundative releases in apple orchards

    Directory of Open Access Journals (Sweden)

    Valérie-Anne Dumont

    2011-12-01

    Full Text Available The rosy apple aphid, Dysaphis plantaginea Pass., is a major pest in apple orchards in Belgium. Two micro-hymenopteran parasitoids Aphidius matricariae Haliday and Ephedrus cerasicola Stary are potentially capable of controlling this pest. However, when released in orchards the adult parasitoids tend to disperse. Based on the results of previous work it is proposed that the reason is that the artificial diet in which they are raised does not contain the odors that enable the parasitoids to identify the habitat where there are suitable aphid hosts. To optimize the control and make it economically effective it is important to reduce dispersal. This might be done by conditioning parasitoids during rearing by exposing them to the odors associated with orchards. The odor used in this study was a hydrodistillate of apple leaves, the main host-plant of the targeted aphid. Two methods of conditioning were used: 1 soaking mummies of the parasitoid in p ure hydrodistillate, 2 including a defined concentration of hydrodistillate in the artificial diet used for rearing the parasitoid. They were exposed to either a dilution of 100×, 200× and 1000× in two consecutive generations. The response of adult parasitoids to odors was determined using a dual choice olfactometer. Of the E. cerasicola conditioned by soaking the mummies 70–75% of individuals were attracted to the odor of plants infested with D. plantaginea compared to the 55–60% in the controls. The A.matricariae that were conditioned by feeding them artificial diets containing different concentrations of apple odor for one or two generations, showed no preference for the odor of apple leaves. Second generation adults of E. cerasicola exposed to a 200 times dilution of pure hydrodistillate showed a more marked response to apple odor.

  10. PRODUCTION UNDER CONTROLLED CONDITIONS OF “CASU MARZU” CHEESE: EFFECT OF THE Piophila Casei COLONIZATION ON MICROBIAL AND CHEMICAL COMPOSITION OF THE CHEESES

    Directory of Open Access Journals (Sweden)

    M Coinu

    2013-02-01

    Full Text Available The aim of the present study was to evaluate the effect of the Piophila casei colonization under controlled conditions on “casu marzu”, a typical Sardinian sheep milk cheese. Three batches of two different kind of cheese (PO, holed paste and PC, firm paste were produced in duplicate (test and control. Test cheeses were exposed to the Piophila casei colonization in a conditioned store room, while control cheeses were suitably protected. All the samples were analyzed at 0, 10, 30, 60 and 90 days from the production. The pH and aw, the chemical composition and the microbiological parameters (food safety and process hygiene criteria were determined. The colonization was unhomogeneous between the batches: PO cheeses were more easily colonized and showed more intense proteolysis and lipolysis respect to PC cheeses. The microbiological parameters were strongly affected by the experimental process conditions. The authors discuss about the opportunity of a controlled production of “casu marzu” and the implications to the health of consumers.

  11. Distributed adaptive asymptotically consensus tracking control of uncertain Euler-Lagrange systems under directed graph condition.

    Science.gov (United States)

    Wang, Wei; Wen, Changyun; Huang, Jiangshuai; Fan, Huijin

    2017-11-01

    In this paper, a backstepping based distributed adaptive control scheme is proposed for multiple uncertain Euler-Lagrange systems under directed graph condition. The common desired trajectory is allowed totally unknown by part of the subsystems and the linearly parameterized trajectory model assumed in currently available results is no longer needed. To compensate the effects due to unknown trajectory information, a smooth function of consensus errors and certain positive integrable functions are introduced in designing virtual control inputs. Besides, to overcome the difficulty of completely counteracting the coupling terms of distributed consensus errors and parameter estimation errors in the presence of asymmetric Laplacian matrix, extra information transmission of local parameter estimates are introduced among linked subsystem and adaptive gain technique is adopted to generate distributed torque inputs. It is shown that with the proposed distributed adaptive control scheme, global uniform boundedness of all the closed-loop signals and asymptotically output consensus tracking can be achieved. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  12. Influence of water pollution on the growth and pigment concentration of the microalgae Phaeodactylum tricornutum Bohlin (Bacillariophyta).

    Science.gov (United States)

    Zhuravel, Elena V; Markina, Zhanna V; Aizdaicher, Nina A

    2012-05-01

    The aim of the work was to study the influence of the water taken from one of the most polluted parts of the Peter the Great Bay (the Japan Sea), the Nakhodka Bay, on the growth and chlorophyll a concentration in the cells of microalga P. tricornutum Bohlin (Bacillariophyta). The estimation of the dynamics of cell number growth and chlorophyll a concentration in the cells of microalga grown in the water from the Nakhodka Bay was made. At the same time, in 2007-2008, the main hydrochemical parameters, such as water salinity, dissolved oxygen concentration, BOD(5), organic and mineral phosphates concentration, anionic surfactants, and total petroleum hydrocarbons, were determined. It is shown that in July 2007, when most hydrochemical parameters were lower than the maximum permissible level, the culture growth and chlorophyll a contents in the cells did not differ from the control for certain. In other seasons these indices differed greatly from the control. The positive correlation between the concentration of dissolved oxygen, phosphates, petroleum hydrocarbons, and the number of microalga cells, grown in the water from the Nakhodka Bay, was shown.

  13. A new shape reproduction method based on the Cauchy-condition surface for real-time tokamak reactor control

    International Nuclear Information System (INIS)

    Kurihara, K.

    2000-01-01

    A new shape reproduction method is investigated on the basis of an applied mathematical approach. An analytically exact solution of Maxwell's equations in a static current field yields an (boundary) integral equation. In application of this equation to tokamak plasma shape reproduction, it is made clear that a Cauchy condition (both Dirichlet and Neumann conditions) on a hypothetical surface is necessarily identified. To calculate the Cauchy condition using magnetic sensor signals, conversion to numerical formulation of this method is conducted. Then, reproduction errors by this method are evaluated through two numerical tests: The first test uses ideal signals produced from a full equilibrium code in the JT-60 geometry, and the second test uses actual sensor signals in JT-60 experiments. In addition, it is shown that positioning and shape of the Cauchy condition surface is insensitive to reproduction error. Finally, this method is clarified to have preferable features for real-time tokamak reactor control

  14. Geochemical and isotopic data for restricting seawater intrusion and groundwater circulation in a series of typical volcanic islands in the South China Sea.

    Science.gov (United States)

    Zhang, Wenjie; Chen, Xi; Tan, Hongbing; Zhang, Yanfei; Cao, Jifu

    2015-04-15

    The decline of groundwater table and deterioration of water quality related to seawater have long been regarded as a crucial problem in coastal regions. In this work, a hydrogeologic investigation using combined hydrochemical and isotopic approaches was conducted in the coastal region of the South China Sea near the Leizhou peninsular to provide primary insight into seawater intrusion and groundwater circulation. Hydrochemical and isotopic data show that local groundwater is subjected to anthropogenic activities and geochemical processes, such as evaporation, water-rock interaction, and ion exchange. However, seawater intrusion driven by the over-exploitation of groundwater and insufficient recharge is the predominant factor controlling groundwater salinization. Systematic and homologic isotopic characteristics of most samples suggest that groundwater in volcanic area is locally recharged and likely caused by modern precipitation. However, very depleted stable isotopes and extremely low tritium of groundwater in some isolated aquifers imply a dominant role of palaeowater. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Application of constraint satisfaction algorithms for conditioning and packing activated control rod assemblies in MOSAIK"R-casks. Application of constraint satisfaction algorithms for conditioning and packaging 160 control rod assemblies

    International Nuclear Information System (INIS)

    Harding, P.J.

    2017-01-01

    In the wake of the decommissioning of numerous nuclear power plants in Germany, techniques to reduce the number of costly waste casks or containers are sought after. The large bandwidth of limits (dose rate, mass, individual nuclide activities, chemical composition...) the waste packages have to comply with for both interim storage facilities and the repository Konrad render the manual planning of packaging concepts prohibitive. However, in the past, the planning for packaging has been performed in this way, albeit on the basis of several facilitating assumptions. Surprisingly, to the best of our knowledge, the automated computer-assisted generation of packaging plans for radioactive waste has not been demonstrated previously. In this talk we demonstrate how the conditioning and packing of 160 control rod assemblies was optimised using constraint satisfaction algorithms. These algorithms can be executed by a computer in a few minutes, thus considerably accelerating the generation of packaging plans, while optimising the utilisation of the waste casks and containers with respect to mass, activity, dose rate, etc. This automated and computer-assisted procedure took into account complex logistical boundary conditions present during decommissioning, such as space requirements, the sequence of the waste and the (lack of) availability of suitable waste casks. In addition, packaging concepts based on several scenarios (cask availability, space requirements,...) were easily and automatically generated once the packaging rules had been coded. We demonstrate the successful application of these algorithms to a real packaging campaign of control rod assemblies of a boiling water reactor, for which excellent results were achieved. We also present an outlook of a much larger scale project, in which the logistics and storage of radioactive waste packages is mathematically optimised. Finally, we give prospects on these techniques to others, similar logistical problems currently

  16. Application of T2 Control Charts and Hidden Markov Models in Condition-Based Maintenance at Thermoelectric Power Plants

    Directory of Open Access Journals (Sweden)

    Emilija Kisić

    2015-01-01

    Full Text Available An innovative approach to condition-based maintenance of coal grinding subsystems at thermoelectric power plants is proposed in the paper. Coal mill grinding tables become worn over time and need to be replaced through time-based maintenance, after a certain number of service hours. At times such replacement is necessary earlier or later than prescribed, depending on the quality of the coal and of the grinding table itself. Considerable financial losses are incurred when the entire coal grinding subsystem is shut down and the grinding table found to not actually require replacement. The only way to determine whether replacement is necessary is to shut down and open the entire subsystem for visual inspection. The proposed algorithm supports condition-based maintenance and involves the application of T2 control charts to distinct acoustic signal parameters in the frequency domain and the construction of Hidden Markov Models whose observations are coded samples from the control charts. In the present research, the acoustic signals were collected by coal mill monitoring at the thermoelectric power plant “Kostolac” in Serbia. The proposed approach provides information about the current condition of the grinding table.

  17. THE APPLICATION OF COMPOSITE MATERIALS IN MODERN AVIATION AND CONTROL OF ITS CONDITION DURING DESIGN SERVICE GOAL

    Directory of Open Access Journals (Sweden)

    A. V. Zibitsky

    2014-01-01

    Full Text Available This article has a purpose to give a brief review of usage of composite materials in the structure of modern civil aircraft. The current condition of civil aviation was analyzed, serious problems were determined and possible achievements in the future were discussed. Advantages and disadvantages of composite materials were analyzed, non-destructive methods of control were reviewed and the necessity to design new method, which allows to control the integrity of structure in real time during design service goal of the aircraft (the concept of “clever material” was shown.

  18. Phytoplankton in the cooling pond of a nuclear fuel plant. II. Spectral analysis

    International Nuclear Information System (INIS)

    Tokarskaya, Z.B.; Smagin, A.I.; Ryzhkov, E.G.; Nikitina, L.V.

    1995-01-01

    This study continues investigations into the development dynamics of phytoplankton and hydrochemical and meteorological factors over a periods of 26 years in the cooling pond of the Mayak Production Association in the Kyzyl-Trash Lake. The aim is to evaluate the long-term oscillations in phytoplankton owing to changes in hydrochemical and meteorological factors. 6 refs., 2 figs., 1 tab

  19. Investigation on output capacity control strategy of variable refrigerant flow air conditioning system with multi-compressor

    International Nuclear Information System (INIS)

    Tu, Qiu; Zou, Deqiu; Deng, Chenmian; Zhang, Jie; Hou, Lifeng; Yang, Min; Nong, Guicai; Feng, Yuhai

    2016-01-01

    Highlights: • The control model of compressor output capacity has been built. • The control strategy of compressor switching has been presented. • The switching process of standard compressor has been described. • The characteristics of EER and noise have been presented. • The control strategy and model have been proved by experiments. - Abstract: A set of 14 HP variable refrigerant flow air conditioning system (VRF AC) with multi-compressor has been designed, and the output capacity control strategy of compressor(s) including the switching control model of standard compressor has been built. In the output capacity control model, a certain suction pressure is used as the pressure control target to adjust the output capacity of compressors, and a little pressure fluctuation is taken into account to amend the target pressure. Furthermore, in the compressor switching control model, the most favorable operation frequency region is determined on base of the energy efficiency characteristic and noise characteristic of the compressor. And, in order to solve the large fluctuation problem of the system running and frequent ON-OFF action of the standard compressor, the equal output capacity switching principle can be used to determine the thermo-on and thermo-off switched frequency points, and control the switching process of the compressor. Experiments demonstrate the feasibility of this control strategy to ensure the stability and reliability, improve the energy efficiency and reduce the compressor noise.

  20. Seedling Emergence and Phenotypic Response of Common Bean Germplasm to Different Temperatures under Controlled Conditions and in Open Field.

    Science.gov (United States)

    De Ron, Antonio M; Rodiño, Ana P; Santalla, Marta; González, Ana M; Lema, María J; Martín, Isaura; Kigel, Jaime

    2016-01-01

    Rapid and uniform seed germination and seedling emergence under diverse environmental conditions is a desirable characteristic for crops. Common bean genotypes (Phaseolus vulgaris L.) differ in their low temperature tolerance regarding growth and yield. Cultivars tolerant to low temperature during the germination and emergence stages and carriers of the grain quality standards demanded by consumers are needed for the success of the bean crop. The objectives of this study were (i) to screen the seedling emergence and the phenotypic response of bean germplasm under a range of temperatures in controlled chamber and field conditions to display stress-tolerant genotypes with good agronomic performances and yield potential, and (ii) to compare the emergence of bean seedlings under controlled environment and in open field conditions to assess the efficiency of genebanks standard germination tests for predicting the performance of the seeds in the field. Three trials were conducted with 28 dry bean genotypes in open field and in growth chamber under low, moderate, and warm temperature. Morpho-agronomic data were used to evaluate the phenotypic performance of the different genotypes. Cool temperatures resulted in a reduction of the rate of emergence in the bean genotypes, however, emergence and early growth of bean could be under different genetic control and these processes need further research to be suitably modeled. Nine groups arose from the Principal Component Analysis (PCA) representing variation in emergence time and proportion of emergence in the controlled chamber and in the open field indicating a trend to lower emergence in large and extra-large seeded genotypes. Screening of seedling emergence and phenotypic response of the bean germplasm under a range of temperatures in controlled growth chambers and under field conditions showed several genotypes, as landraces 272, 501, 593, and the cultivar Borlotto, with stress-tolerance at emergence, and high yield

  1. Seedling Emergence and Phenotypic Response of Common Bean Germplasm to Different Temperatures under Controlled Conditions and in Open Field

    Directory of Open Access Journals (Sweden)

    Antonio M. DE RON

    2016-08-01

    Full Text Available Rapid and uniform seed germination and seedling emergence under diverse environmental conditions is a desirable characteristic for crops. Common bean genotypes (Phaseolus vulgaris L. differ in their low temperature tolerance regarding growth and yield. Cultivars tolerant to low temperature during the germination and emergence stages and carriers of the grain quality standards demanded by consumers are needed for the success of the bean crop. The objectives of this study were i to screen the seedling emergence and the phenotypic response of bean germplasm under a range of temperatures in controlled chamber and field conditions to display stress-tolerant genotypes with good agronomic performances and yield potential, and ii to compare the emergence of bean seedlings under controlled environment and in open field conditions to assess the efficiency of genebanks standard germination tests for predicting the performance of the seeds in the field. Three trials were conducted with 28 dry bean genotypes in open field and in growth chamber under low, moderate and warm temperature. Morpho-agronomic data were used to evaluate the phenotypic performance of the different genotypes. Cool temperatures resulted in a reduction of the rate of emergence in the bean genotypes, however, emergence and early growth of bean could be under different genetic control and these processes need further research to be suitably modeled. Nine groups arose from the Principal Component Analysis (PCA representing variation in emergence time and proportion of emergence in the controlled chamber and in the open field indicating a trend to lower emergence in large and extra-large seeded genotypes. Screening of seedling emergence and phenotypic response of the bean germplasm under a range of temperatures in controlled growth chambers and under field conditions showed several genotypes, as landraces 272, 501, 593 and the cultivar Borlotto, with stress-tolerance at emergence and high

  2. [Testing of the effect of classic conditioning stimuli in human experiment by means of the transfer of control paradigm].

    Science.gov (United States)

    Wolter, J

    1999-01-01

    Pavlovian conditioning in animals is often evaluated by means of transfer of control experiments. With human subjects, however, only very few studies have been conducted and the outcomes were often not in accordance with theoretical explanations based on studies with animals. A theoretical framework is presented that tries to integrate the results of the human conditioning paradigm and the animal conditioning paradigm as well, with reference to the well-known Yerkes-Dodson law. The experimental study with human subjects (N = 24) confirmed the predictions out of this framework, when a procedure similar to animal research is applied.

  3. Patients with musculoskeletal conditions do less vigorous physical activity and have poorer physical fitness than population controls: a cross-sectional study.

    Science.gov (United States)

    Moseng, T; Tveter, A T; Holm, I; Dagfinrud, H

    2014-12-01

    To compare physical activity and physical fitness in patients with various musculoskeletal conditions receiving physiotherapy in primary care with population controls. Cross-sectional. One hundred and sixty-seven patients with musculoskeletal conditions receiving physiotherapy in primary care and 313 population controls from various settings and geographical areas. Physical activity was measured with the International Physical Activity Questionnaire short-form (IPAQ-sf) and reported in metabolic equivalents (METs). The 6-minute walk test and 30-second sit-to-stand test reflected cardiorespiratory endurance and muscular strength, respectively. Differences in physical activity between the groups were explored using the Mann-Whitney U-test. The patient group reported significantly less vigorous activity compared with the control group {median 0 [interquartile range (IQR) 0 to 960] vs median 240 [IQR 0 to 1440] MET minutes/week, respectively)} (P=0.001). A similar proportion of patients (68%) and controls (75%) reached the recommended level of health-enhancing physical activity (P=0.11). Linear regression analyses adjusted for age, body mass index and gender showed significantly poorer fitness in the patient group compared with the control group, reflected by the 6-minute walk test and the 30-second sit-to-stand test {mean difference 69m [95% confidence interval (CI) 52 to 85; P≤0.001] and six repetitions [95% CI 5 to 7; P≤0.001], respectively}. Patients with various long-term musculoskeletal conditions receiving physiotherapy in primary care had significantly poorer physical fitness and reported less vigorous physical activity compared with population controls. Copyright © 2014 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  4. Voltage controller design for air conditioning; Diseno de controlador de voltaje para aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Andrade, R; Lopez Villalobos, J.J; Valderrama Chairez, J; Ramirez, R.L. [Instituto Tecnologico de Nuevo Leon, Guadalupe, Nuevo Leon (Mexico)]. E-mails: roxana_garciaandrade@yahoo.com; xe2n@yahoo.com.mx; jose.valderrama@ieee.org

    2013-03-15

    This paper discusses the design of a voltage controller for an air conditioning system in order to generate additional power in activation or startup of the system, for which as a first stage is presented the modeling power generation of electric current through alternative means, such as solar energy. The results of this study will be the basis for development of the physical prototype of this system controller. [Spanish] El presente trabajo trata sobre el diseno de un controlador de voltaje para un sistema de aire acondicionado con el fin de generar energia adicional en la activacion o arranque de dicho sistema, para lo cual como primer fase se presenta el modelado de la generacion de corriente electrica mediante medios alternos, como lo es la energia solar. Los resultados de este trabajo seran la base para desarrollo del prototipo fisico de este sistema controlador.

  5. Unique genetic loci identified for emotional behavior in control and chronic stress conditions.

    Directory of Open Access Journals (Sweden)

    Kimberly AK Carhuatanta

    2014-10-01

    Full Text Available An individual’s genetic background affects their emotional behavior and response to stress. Although studies have been conducted to identify genetic predictors for emotional behavior or stress response, it remains unknown how prior stress history alters the interaction between an individual’s genome and their emotional behavior. Therefore, the purpose of this study is to identify chromosomal regions that affect emotional behavior and are sensitive to stress exposure. We utilized the BXD behavioral genetics mouse model to identify chromosomal regions that predict fear learning and emotional behavior following exposure to a control or chronic stress environment. 62 BXD recombinant inbred strains and C57BL/6 and DBA/2 parental strains underwent behavioral testing including a classical fear conditioning paradigm and the elevated plus maze. Distinct quantitative trait loci (QTLs were identified for emotional learning, anxiety and locomotion in control and chronic stress populations. Candidate genes, including those with already known functions in learning and stress were found to reside within the identified QTLs. Our data suggest that chronic stress history reveals novel genetic predictors of emotional behavior.

  6. Co-ordinated Control Strategy for Hybrid Wind Farms with PMSG and FSIG under Unbalanced Grid Voltage Condition

    DEFF Research Database (Denmark)

    Zeng, Xin; Yao, Jun; Chen, Zhiqian

    2016-01-01

    -sequence current from the PMSG-based wind farm by the modified negative-sequence voltage and current double closed-loop control system is then developed. Finally, the correctness of theoretical analysis and the effectiveness of the proposed control strategy are validated by the experimental results....... to inject negative-sequence current for decreasing voltage unbalance factor (VUF) at point of common coupling (PCC), the double grid frequency oscillations in electromagnetic torque, active and reactive power output from the FSIG-based wind farm can be suppressed. In this paper, the maximum amplitude...... of the negative-sequence current provided by the PMSG-based wind farm under different average active power output and different VUF conditions is deduced, and the impacts of its phase angle on the VUF mitigation control effect are further studied. The improved control strategy of injecting negative...

  7. Integrating geophysical and hydrochemical borehole-log measurements to characterize the Chalk aquifer, Berkshire, United Kingdom

    Science.gov (United States)

    Schürch, Marc; Buckley, David

    2002-09-01

    Geophysical and hydrochemical borehole-logging techniques were integrated to characterize hydraulic and hydrogeochemical properties of the Chalk aquifer at boreholes in Berkshire, UK. The down-hole measurements were made to locate fissures in the chalk, their spatial extent between boreholes, and to determine the groundwater chemical quality of the water-bearing layers. The geophysical borehole logging methods used were caliper, focused resistivity, induction resistivity, gamma ray, fluid temperature, fluid electrical conductivity, impeller and heat-pulse flowmeter, together with borehole wall optical-imaging. A multiparameter data transmitter was used to measure groundwater temperature, electrical conductivity, dissolved oxygen, pH, and redox potential of the borehole fluid down-hole. High permeability developed at the Chalk Rock by groundwater circulation provides the major flow horizon at the Banterwick Barn study site and represents a conduit system that serves as an effective local hydraulic connection between the boreholes. The Chalk Rock includes several lithified solution-ridden layers, hardgrounds, which imply a gap in sedimentation possibly representing an unconformity. Lower groundwater temperature, high dissolved-oxygen content, and flowmeter evidence of preferential groundwater flow in the Chalk Rock indicated rapid groundwater circulation along this horizon. By repeating the logging at different times of the year under changing hydraulic conditions, other water-inflow horizons within the Chalk aquifer were recognized. Résumé. Des techniques géophysiques et hydrochimiques de diagraphies en forage ont été mises en oeuvre pour caractériser les propriétés hydrauliques et hydrogéochimiques de l'aquifère de la craie dans des forages du Berkshire (Grande-Bretagne). Les mesures en descente ont été faites pour localiser les fissures dans la craie et leur développement spatial entre forages, et pour déterminer la qualité de l'eau souterraine des

  8. Relapse Prevention in Major Depressive Disorder: Mindfulness-Based Cognitive Therapy Versus an Active Control Condition

    Science.gov (United States)

    Shallcross, Amanda J.; Gross, James J.; Visvanathan, Pallavi D.; Kumar, Niketa; Palfrey, Amy; Ford, Brett Q.; Dimidjian, Sona; Shirk, Stephen; Holm-Denoma, Jill; Goode, Kari M.; Cox, Erica; Chaplin, William; Mauss, Iris B.

    2015-01-01

    Objective We evaluated the comparative effectiveness of Mindfulness-based cognitive therapy (MBCT) versus an active control condition (ACC) for depression relapse prevention, depressive symptom reduction, and improvement in life satisfaction. Method Ninety-two participants in remission from Major Depressive Disorder with residual depressive symptoms were randomized to either an 8-week MBCT or a validated ACC that is structurally equivalent to MBCT and controls for non-specific effects (e.g., interaction with a facilitator, perceived social support, treatment outcome expectations). Both interventions were delivered according to their published manuals. Results Intention-to-treat analyses indicated no differences between MBCT and ACC in depression relapse rates or time to relapse over a 60-week follow-up. Both groups experienced significant and equal reductions in depressive symptoms and improvements in life satisfaction. A significant quadratic interaction (group x time) indicated that the pattern of depressive symptom reduction differed between groups. The ACC experienced immediate symptom reduction post-intervention and then a gradual increase over the 60-week follow-up. The MBCT group experienced a gradual linear symptom reduction. The pattern for life satisfaction was identical but only marginally significant. Conclusions MBCT did not differ from an ACC on rates of depression relapse, symptom reduction, or life satisfaction, suggesting that MBCT is no more effective for preventing depression relapse and reducing depressive symptoms than the active components of the ACC. Differences in trajectory of depressive symptom improvement suggest that the intervention-specific skills acquired may be associated with differential rates of therapeutic benefit. This study demonstrates the importance of comparing psychotherapeutic interventions to active control conditions. PMID:26371618

  9. Evaluating the impact of a disease management program for chronic complex conditions at two large northeast health plans using a control group methodology.

    Science.gov (United States)

    Schwerner, Henry; Mellody, Timothy; Goldstein, Allan B; Wansink, Daryl; Sullivan, Virginia; Yelenik, Stephan N; Charlton, Warwick; Lloyd, Kelley; Courtemanche, Ted

    2006-02-01

    The objective of this study was to observe trends in payer expenditures for plan members with one of 14 chronic, complex conditions comparing one group with a disease management program specific to their condition (the intervention group) and the other with no specific disease management program (the control group) for these conditions. The authors used payer claims and membership data to identify members eligible for the program in a 12-month baseline year (October 2001 to September 2002) and a subsequent 12-month program year (October 2002 to September 2003). Two payers were analyzed: one health plan with members primarily in New Jersey (AmeriHealth New Jersey [AHNJ]), where the disease management program was offered, and one affiliated large plan with members primarily in the metro Philadelphia area, where the program was not offered. The claims payment policy for both plans is identical. Intervention and control groups were analyzed for equivalence. The analysis was conducted in both groups over identical time periods. The intervention group showed statistically significant (p control group. Intervention group members showed a reduction in expenditures of -8%, while control group members showed an increase of +10% over identical time periods. Subsequent analyses controlling for outliers and product lines served to confirm the overall results. The disease management program is likely responsible for the observed difference between the intervention and control group results. A well-designed, targeted disease management program offered by a motivated, supportive health plan can play an important role in cost improvement strategies for members with complex, chronic conditions.

  10. Which key properties controls the preferential transport in the vadose zone under transient hydrological conditions

    Science.gov (United States)

    Groh, J.; Vanderborght, J.; Puetz, T.; Gerke, H. H.; Rupp, H.; Wollschlaeger, U.; Stumpp, C.; Priesack, E.; Vereecken, H.

    2015-12-01

    % arrival time and potential key soil properties, site factors and boundary conditions will be presented in order to identify key properties which control the preferential transport in the vadose zone under transient hydrological conditions.

  11. Calibration of regional palaeohydrogeology and sensitivity analysis using hydrochemistry data in site investigations

    International Nuclear Information System (INIS)

    Hunter, F.M.I.; Hartley, L.J.; Hoch, A.; Jackson, C.P.; McCarthy, R.; Marsic, N.; Gylling, B.

    2008-01-01

    A transient coupled regional model of groundwater flow and solute transport has been developed, which allows the use of hydrochemical data to calibrate the model input parameters. The methodology has been illustrated using examples from the Simpevarp area in south-eastern Sweden which is being considered for geological disposal of spent nuclear fuel. The 3-dimensional model includes descriptions of spatial heterogeneity, density driven flow, rock matrix diffusion and transport and mixing of different water types, and has been simulated between 8000 BC and 2000 AD. Present-day analyses of major elemental ions and stable isotopes have been used to calibrate the model, which has then been cross checked against measured hydraulic conductivities, and against the hydrochemical interpretation of reference water mixing fractions. The key hydrogeological model sensitivities have been identified using the calibrated model and are found to include high sensitivity to the top surface flow boundary condition, the influence of variations in fracture transmissivity in different orientations (anisotropy), spatial heterogeneity in the deterministic regional deformation zones and the spacing between water bearing fractures (in terms of its effect on matrix diffusion)

  12. The role of anthropogenic and natural factors in shaping the geochemical evolution of groundwater in the Subei Lake basin, Ordos energy base, Northwestern China.

    Science.gov (United States)

    Liu, Fei; Song, Xianfang; Yang, Lihu; Han, Dongmei; Zhang, Yinghua; Ma, Ying; Bu, Hongmei

    2015-12-15

    Groundwater resources are increasingly exploited for industrial and agricultural purposes in many arid regions globally, it is urgent to gain the impact of the enhanced anthropogenic pressure on the groundwater chemistry. The aim of this study was to acquire a comprehensive understanding of the evolution of groundwater chemistry and to identify the impact of natural and anthropogenic factors on the groundwater chemistry in the Subei Lake basin, Northwestern China. A total of 153 groundwater samples were collected and major ions were measured during the three campaigns (August and December 2013, May 2014). At present, the major hydrochemical facies in unconfined groundwater are Ca-Mg-HCO3, Ca-Na-HCO3, Na-Ca-HCO3, Na-HCO3, Ca-Mg-SO4 and Na-SO4-Cl types, while the main hydrochemical facies in confined groundwater are Ca-Mg-HCO3, Ca-Na-HCO3, Na-Ca-HCO3, Ca-HCO3 and Na-HCO3 types. Relatively greater seasonal variation can be observed in the chemical constituents of confined groundwater than that of unconfined groundwater. Rock weathering predominates the evolution of groundwater chemistry in conjunction with the cation exchange, and the dissolution/precipitation of gypsum, halite, feldspar, calcite and dolomite are responsible for the chemical constituents of groundwater. Anthropogenic activities can be classified as: (1) groundwater overexploitation; (2) excessive application of fertilizers in agricultural areas. Due to intensive groundwater pumping, the accelerated groundwater mineralization resulted in the local changes in hydrochemical facies of unconfined groundwater, while the strong mixture, especially a large influx of downward leakage from the unconfined aquifer into the confined aquifer, played a vital role in the fundamental variation of hydrochemical facies in confined aquifer. The nitrate contamination is mainly controlled by the local hydrogeological settings coupled with the traditional flood irrigation. The deeper insight into geochemical evolution of

  13. The characteristics of hydrogeochemical zonation of groundwater in inland plain

    Science.gov (United States)

    Xin-yu, HOU; Li-ting, XING; Yi, YANG; Wen-jing, ZHANG; Guang-yao, CHI

    2018-05-01

    To find out the hydrochemical zoning of groundwaterin the inland plain, taking Jiyang plain as an example, based on mathematical statistics, ion ratio coefficient and isotopic analysis method, the characteristics of water chemical composition and its zoning at different depths of 500m were studied. The result shows: ①The groundwater flow system in the study area can be divided into local flow system, intermediate flow system and regional flow system. ②The hydrochemical type of shallow groundwater is complex. The hydrochemical types of middle confined water are mainly ClṡSO4—MgṡNa and SO4ṡCl—NaṡMg. The deep confined water is mainly HCO3. ③The TDS of shallow groundwater increases gradually along the direction of groundwater flow. ④The shallow saltwater and freshwater are alternately distributed in horizontal direction, and saltwater is distributed sporadically in the interfluve area with sporadic punctate or banded, and hydrochemical types are mainly ClṡSO4—NaṡMgṡCa. Conclusion: Groundwater in the study area is affected by complicated hydrogeochemical action, mainly in the form of filtration, cation exchange and evaporation. The inland plain area is characterized by hydrogeochemical zonation in horizontal and vertical.

  14. The impact of geology on the migration of fluorides in mineral waters of the Bukulja and Brajkovac pluton area, Serbia

    Directory of Open Access Journals (Sweden)

    Papić Petar

    2012-01-01

    Full Text Available One of the hydrogeochemical parameters that classify groundwater as mineral water is the content of fluoride ions. Their concentration is both important and limited for bottled mineral waters. Hydrochemical research of mineral waters in the surrounding area of Bukulja and Brajkovac pluton, in central Serbia, was conducted in order to define the chemical composition and genesis of these waters. They are carbonated waters, with content of fluoride ranging from 0.2 up to 6.6 mg/L. Since hydrochemical analyses showed variations in the major water chemistry, it was obvious that, apart from hydrochemical research, some explorations of the structure of the regional terrain would be inevitable. For these purposes, some additional geological research was performed, creating an adequate basis for the interpretation of the genesis of these carbonated mineral waters. The results confirmed the significance of the application of hydrochemical methods in the research of mineral waters. The work tended to emphasize that “technological treatment” for decreasing the concentration of fluoride in mineral waters occurs in nature, indicating the existence of natural defluoridization. [Projekat Ministarstva nauke Republike Srbije, br. 43004

  15. Colloid characterization and in situ release in shallow groundwater under different hydrogeology conditions.

    Science.gov (United States)

    Zhou, Jingjing; Liu, Dan; Zhang, Wenjing; Chen, Xuequn; Huan, Ying; Yu, Xipeng

    2017-06-01

    Changes to groundwater hydrodynamics and chemistry can lead to colloid release that can have a major impact on the groundwater environment. To analyze the effects of colloid release caused by artificial groundwater recharge, field and laboratory tests on colloid characterization and colloid release were conducted. The field tests were carried out at an artificial recharge test site in Shandong Province. In the field investigation, one recharge water sample and five groundwater samples were collected and filtered through three levels of ultrafiltration membranes, with pore sizes of 0.45 μm, 100 kDa, and 50 kDa. The field results indicated that the colloid mass concentrations in groundwater retained between membranes with pore sizes of 100 kDa-0.45 μm and 50 kDa-100 kDa were 19 and 62 mg/L, respectively. In recharge water, the colloid mass concentrations retained by 100-kDa-0.45-μm and 50-kDa-100-kDa membranes were 3 and 99 mg/L, respectively. Colloids detected on the ultrafiltration membranes were mainly inorganic between 100 kDa and 0.45 μm, and mainly organic between 50 and 100 kDa. Based on the field colloid investigation results, the organic colloid was chosen in the laboratory experiments to reveal its release behavior under different conditions. Porous media diameter, flux, ionic strength (IS), and ion valence were changed to determine their influences on organic colloid concentration outflow from undisturbed porous media. The experiment's results indicate that decreasing the diameter, and increasing the flux, ionic strength, and the number of divalent cations, can promote organic colloid release. The organic colloid release rate in the early stage was high and is thus likely to affect the quality of groundwater. The results provide a useful scientific basis for minimizing changes to hydrodynamic and hydrochemical conditions during artificial recharge, thus safeguarding groundwater quality.

  16. A Randomized Controlled Trial of Intensive Sleep Retraining (ISR): A Brief Conditioning Treatment for Chronic Insomnia

    Science.gov (United States)

    Harris, Jodie; Lack, Leon; Kemp, Kristyn; Wright, Helen; Bootzin, Richard

    2012-01-01

    Study Objective: To investigate the effectiveness of intensive sleep retraining in comparison and combination with traditional behavioral intervention for chronic primary insomnia. Participants: Seventy-nine volunteers with chronic sleep-onset insomnia (with or without sleep maintenance difficulties) were randomly assigned either to intensive sleep retraining (ISR), stimulus control therapy (SCT), ISR plus SCT, or the control (sleep hygiene) treatment condition. Intervention: ISR treatment consisted of 50 sleep onset trials over a 25-h sleep deprivation period. Measurements and Results: Treatment response was assessed with sleep diary, activity monitoring, and questionnaire measures. The active treatment groups (ISR, SCT, ISR+SCT) all resulted in significant improvements in sleep onset latency and sleep efficiency, with moderate to large effect sizes from pre- to post-treatment. Wake time after sleep onset decreased significantly in the SCT and ISR+SCT groups. Total sleep time increased significantly in the ISR and ISR+SCT treatment groups. Participants receiving ISR (ISR, ISR+SCT) experienced rapidly improved SOL and TST during treatment, suggesting an advantage of rapid improvements in sleep in response to ISR. Although there were few statistically significant differences between groups on individual variables, ISR+SCT resulted in consistently larger effect sizes of change than other treatments, including questionnaire measures of sleep quality, sleep self-efficacy, and daytime functioning. The combination treatment group (ISR+SCT) showed trends to outperform other active treatment groups with fewer treatment dropouts, and a greater proportion of treatment responders with 61% reaching “good sleeper” status. Treatment gains achieved at post-treatment in the active treatment groups were largely maintained throughout follow-up periods to 6 months. Conclusion: This 25-hour intensive conditioning treatment for chronic insomnia can produce rapid improvements in

  17. Groundwater flow modeling of periods with temperate climate conditions for use in a safety assessment of a repository for spent nuclear fuel - 59154

    International Nuclear Information System (INIS)

    Joyce, Steven; Hartley, Lee; Simpson, Trevor

    2012-01-01

    Document available in abstract form only. Full text of publication follows: As a part of the license application for a final repository for spent nuclear fuel, the Swedish Nuclear Fuel and Waste Management Company (SKB) has prepared a safety report (SR-Site) that assesses the long-term radiological safety after closure of a repository located at 500 m depth in the Forsmark area, c. 120 km north of Stockholm. The movement and composition of groundwater affect both the key pathways for radionuclide migration and the performance of engineered barriers, and hence are important issues that have to be considered and modelled as part of quantitative assessment calculations. This presentation describes the groundwater flow modelling studies that have been performed to represent the post-closure hydrogeological and hydrochemical situations during temperate climate conditions, and how these are used to support safety assessment calculations and arguments. The collation and implementation of onsite hydrogeological and hydrogeochemical data from the surface based site investigations at Forsmark are used as the basis for defining a reference case for the natural hydrogeological situation at the site (hydrogeological base case). Areas of uncertainty within the current site understanding and the engineered system are examined by a series of flow model variants

  18. Biomimetic propulsion under random heaving conditions, using active pitch control

    Science.gov (United States)

    Politis, Gerasimos; Politis, Konstantinos

    2014-05-01

    Marine mammals travel long distances by utilizing and transforming wave energy to thrust through proper control of their caudal fin. On the other hand, manmade ships traveling in a wavy sea store large amounts of wave energy in the form of kinetic energy for heaving, pitching, rolling and other ship motions. A natural way to extract this energy and transform it to useful propulsive thrust is by using a biomimetic wing. The aim of this paper is to show how an actively pitched biomimetic wing could achieve this goal when it performs a random heaving motion. More specifically, we consider a biomimetic wing traveling with a given translational velocity in an infinitely extended fluid and performing a random heaving motion with a given energy spectrum which corresponds to a given sea state. A formula is invented by which the instantaneous pitch angle of the wing is determined using the heaving data of the current and past time steps. Simulations are then performed for a biomimetic wing at different heave energy spectra, using an indirect Source-Doublet 3-D-BEM, together with a time stepping algorithm capable to track the random motion of the wing. A nonlinear pressure type Kutta condition is applied at the trailing edge of the wing. With a mollifier-based filtering technique, the 3-D unsteady rollup pattern created by the random motion of the wing is calculated without any simplifying assumptions regarding its geometry. Calculated unsteady forces, moments and useful power, show that the proposed active pitch control always results in thrust producing motions, with significant propulsive power production and considerable beneficial stabilizing action to ship motions. Calculation of the power required to set the pitch angle prove it to be a very small percentage of the useful power and thus making the practical application of the device very tractable.

  19. Muscodor albus Volatiles Control Toxigenic Fungi under Controlled Atmosphere (CA Storage Conditions

    Directory of Open Access Journals (Sweden)

    Gordon Braun

    2012-11-01

    Full Text Available Muscodor albus, a biofumigant fungus, has the potential to control post-harvest pathogens in storage. It has been shown to produce over 20 volatile compounds with fungicidal, bactericidal and insecticidal properties. However, M. albus is a warm climate endophyte, and its biofumigant activity is significantly inhibited at temperatures below 5 °C. Conidia of seven mycotoxin producing fungi, Aspergillus carbonarius, A. flavus, A. niger, A. ochraceus, Penicillium verrucosum, Fusarium culmorum and F. graminearum, were killed or prevented from germinating by exposure to volatiles from 2 g M. albus-colonized rye grain per L of headspace in sealed glass jars for 24 h at 20 °C. Two major volatiles of M. albus, isobutyric acid (IBA and 2-methyl-1-butanol (2MB at 50 µL/L and 100 µL/L, respectively, gave differential control of the seven fungi when applied individually at 20 °C. When the fungi were exposed to both IBA and 2MB together, an average of 94% of the conidia were killed or suppressed. In a factorial experiment with controlled atmosphere storage (CA at 3 °C and 72 h exposure to four concentrations of IBA and 2MB combinations, 50 µL/L IBA plus 100 µL/L 2MB killed or suppressed germination of the conidia of all seven fungi. Controlled atmosphere had no significant effect on conidial viability or volatile efficacy. Major volatiles of M. albus may have significant potential to control plant pathogens in either ambient air or CA storage at temperatures below 5 °C. However, combinations of volatiles may be required to provide a broader spectrum of control than individual volatiles.

  20. Stochastic Model Predictive Fault Tolerant Control Based on Conditional Value at Risk for Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Yun-Tao Shi

    2018-01-01

    Full Text Available Wind energy has been drawing considerable attention in recent years. However, due to the random nature of wind and high failure rate of wind energy conversion systems (WECSs, how to implement fault-tolerant WECS control is becoming a significant issue. This paper addresses the fault-tolerant control problem of a WECS with a probable actuator fault. A new stochastic model predictive control (SMPC fault-tolerant controller with the Conditional Value at Risk (CVaR objective function is proposed in this paper. First, the Markov jump linear model is used to describe the WECS dynamics, which are affected by many stochastic factors, like the wind. The Markov jump linear model can precisely model the random WECS properties. Second, the scenario-based SMPC is used as the controller to address the control problem of the WECS. With this controller, all the possible realizations of the disturbance in prediction horizon are enumerated by scenario trees so that an uncertain SMPC problem can be transformed into a deterministic model predictive control (MPC problem. Finally, the CVaR object function is adopted to improve the fault-tolerant control performance of the SMPC controller. CVaR can provide a balance between the performance and random failure risks of the system. The Min-Max performance index is introduced to compare the fault-tolerant control performance with the proposed controller. The comparison results show that the proposed method has better fault-tolerant control performance.