WorldWideScience

Sample records for conditioning methods fo

  1. Removal of organic micro-pollutants (phenol, aniline and nitrobenzene) via forward osmosis (FO) process: Evaluation of FO as an alternative method to reverse osmosis (RO).

    Science.gov (United States)

    Cui, Yue; Liu, Xiang-Yang; Chung, Tai-Shung; Weber, Martin; Staudt, Claudia; Maletzko, Christian

    2016-03-15

    In this study, we have explored and compared the effectiveness of using (1) lab-fabricated forward osmosis (FO) membranes under both FO and reverse osmosis (RO) modes and (2) commercially available RO membranes under the RO mode for the removal of organic micro-pollutants. The lab-fabricated FO membranes are thin film composite (TFC) membranes consisting of a polyamide layer and a porous substrate cast from three different materials; namely, Matrimid, polyethersulfone (PESU) and sulfonated polyphenylene sulfone (sPPSU). The results show that the FO mode is superior to the RO mode in the removal of phenol, aniline and nitrobenzene from wastewater. The rejections of all three TFC membranes to all the three organic micro-pollutants under the FO processes are higher than 72% and can be even higher than 90% for aniline when a 1000 ppm aromatic aqueous solution and 1 M NaCl are employed as feeds. These performances outperform the results obtained from themselves and commercially available RO membranes under the RO mode. In addition, the rejection can be maintained even when treating a more concentrated feed solution (2000 ppm). The removal performance can be further enhanced by using a more concentrated draw solution (2 M). The water flux is almost doubled, and the rejection increment can reach up to 17%. Moreover, it was observed that annealing as a post-treatment would help compact the membrane selective layer and further enhance the separating efficiency. The obtained organic micro-pollutant rejections and water fluxes under various feasible operating conditions indicate that the FO process has potential to be a viable treatment for wastewater containing organic micro-pollutants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Removal of organic micro-pollutants (phenol, aniline and nitrobenzene) via forward osmosis (FO) process: Evaluation of FO as an alternative method to reverse osmosis (RO)

    KAUST Repository

    Cui, Yue

    2016-01-05

    In this study, we have explored and compared the effectiveness of using (1) lab-fabricated forward osmosis (FO) membranes under both FO and reverse osmosis (RO) modes and (2) commercially available RO membranes under the RO mode for the removal of organic micro-pollutants. The lab-fabricated FO membranes are thin film composite (TFC) membranes consisting of a polyamide layer and a porous substrate cast from three different materials; namely, Matrimid, polyethersulfone (PESU) and sulfonated polyphenylene sulfone (sPPSU). The results show that the FO mode is superior to the RO mode in the removal of phenol, aniline and nitrobenzene from wastewater. The rejections of all three TFC membranes to all the three organic micro-pollutants under the FO processes are higher than 72% and can be even higher than 90% for aniline when a 1000 ppm aromatic aqueous solution and 1 M NaCl are employed as feeds. These performances outperform the results obtained from themselves and commercially available RO membranes under the RO mode. In addition, the rejection can be maintained even when treating a more concentrated feed solution (2000 ppm). The removal performance can be further enhanced by using a more concentrated draw solution (2 M). The water flux is almost doubled, and the rejection increment can reach up to 17%. Moreover, it was observed that annealing as a post-treatment would help compact the membrane selective layer and further enhance the separating efficiency. The obtained organic micro-pollutant rejections and water fluxes under various feasible operating conditions indicate that the FO process has potential to be a viable treatment for wastewater containing organic micro-pollutants.

  3. Unusual nighttime impulsive foF2 enhancement below the southern anomaly crest under geomagnetically quiet conditions

    Science.gov (United States)

    Pezzopane, M.; Fagundes, P. R.; Ciraolo, L.; Correia, E.; Cabrera, M. A.; Ezquer, R. G.

    2011-12-01

    An unusual nighttime impulsive electron density enhancement was observed on 6 March 2010 over a wide region of South America, below the southern crest of the equatorial anomaly, under low solar activity and quiet geomagnetic conditions. The phenomenon was observed almost simultaneously by the F2 layer critical frequency (foF2) recorded at three ionospheric stations which are widely distributed in space, namely Cachoeira Paulista (22.4°S, 44.6°W, magnetic latitude 13.4°S), São José dos Campos (23.2°S, 45.9°W, magnetic latitude 14.1°S), Brazil, and Tucumán (26.9°S, 65.4°W, magnetic latitude 16.8°S), Argentina. Although in a more restricted region over Tucumán, the phenomenon was also observed by the total electron content (TEC) maps computed by using measurements from 12 GPS receivers. The investigated phenomenon is very particular because besides being of brief duration, it is characterized by a pronounced compression of the ionosphere. This compression was clearly visible both by the virtual height of the base of the F region (h‧F) recorded at the aforementioned ionospheric stations, and by both the vertical electron density profiles and the slab thickness computed over Tucumán. Consequently, neither an enhanced fountain effect nor plasma diffusion from the plasmasphere can be considered as the single cause of this unusual event. A thorough analysis of isoheight and isofrequency ionosonde plots suggest that traveling ionospheric disturbances (TIDs) caused by gravity wave (GW) propagation could have likely played a significant role in causing the phenomenon.

  4. Evaluation of wood structure using GPR with FO method - Effect of moisture, fibers direction and density

    Science.gov (United States)

    Chinh Maï, Tien; Reci, Hamza; Sbartaï, Zoubir Mehdi; Pajewski, Lara; Marciniak, Marian

    2017-04-01

    This work deals with the potential of GPR method in the evaluation of wood structure in relation with density of wood (different wood species), the orientation of fibers and water content (Maï et al., 2015; Reci et al., 2016). The system of measurements is the georadar type (GPR-ground penetrating radar) composed of an electromagnetic signal generator (SIR 3000 of GSSI), and one couple of antennas, one Transmitter (T) and a Receiver (R) of 1.5GHz center frequency, located in the same box in a fixed distance of 6cm. Six wood samples are tested, three samples of Epicea and three samples of Pine. To compare and analyze the results of dielectric constants, we have used the data on three principal directions (Transvesal, Longitudinal and Radial). We note that the dielectric constant of wood increases with the moisture by mass as a consequence of increasing polarization and the conduction phenomena. This effect is more distinguished when the electric field is polarized parallel to the fibers than in perpendicular direction. The smallest contrasts are observed in the radial direction. We conclude that is more appropriate to evaluate the water content along the parallel direction of fibers. In this case we observe the maximum of contrasts of dielectric contrasts between dry and humidity states. Differences on dielectric constant, spectras and amplitudes are taken between different wood samples. Knowing that the dielectric constant is related to the capacity of polarizing (dependent on the water quantity), the increasing of water content could explain the difference of values obtained for the dielectric constants between two kinds of wood. Acknowledgement The Authors are grateful to COST - European Cooperation in Science and Technology (www.cost.eu) for funding the Action TU1208 "Civil engineering applications of Ground Penetrating Radar" (www.GPRadar.eu). We acknowledge also the French National Research Agency (ANR) for supporting this study through the Xylo-plate project

  5. XSL-FO

    CERN Document Server

    Pawson, Dave

    2002-01-01

    No matter how flexible and convenient digital information has become, we haven't done away with the need to see information in print. Extensible Style Language-Formatting Objects, or XSL-FO, is a set of tools developers and web designers use to describe page printouts of their XML (including XHTML) documents. If you need to produce high quality printed material from your XML documents, then XSL-FO provides the bridge. XSL-FO is one of the few books to go beyond a basic introduction to the technology. While many books touch on XSL-FO in their treatment of XSLT, this book offers in-depth co

  6. The Mineralogy, Geochemistry, and Redox State of Multivalent Cations During the Crystallization of Primitive Shergottitic Liquids at Various (f)O2. Insights into the (f)O2 Fugacity of the Martian Mantle and Crustal Influences on Redox Conditions of Martian Magmas.

    Science.gov (United States)

    Shearer, C. K.; Bell, A. S.; Burger, P. V.; Papike, J. J.; Jones, J.; Le, L.; Muttik, N.

    2016-01-01

    The (f)O2 [oxygen fugacity] of crystallization for martian basalts has been estimated in various studies to range from IW-1 to QFM+4 [1-3]. A striking geochemical feature of the shergottites is the large range in initial Sr isotopic ratios and initial epsilon(sup Nd) values. Studies by observed that within the shergottite group the (f)O2 [oxygen fugacity] of crystallization is highly correlated with these chemical and isotopic characteristics with depleted shergottites generally crystallizing at reduced conditions and enriched shergottites crystallizing under more oxidizing conditions. More recent work has shown that (f)O2 [oxygen fugacity] changed during the crystallization of these magmas from one order of magnitude in Y980459 (Y98) to several orders of magnitude in Larkman Nunatak 06319. These real or apparent variations within single shergottitic magmas have been attributed to mixing of a xenocrystic olivine component, volatile loss-water disassociation, auto-oxidation during crystallization of mafic phases, and assimilation of an oxidizing crustal component (e.g. sulfate). In contrast to the shergottites, augite basalts such as NWA 8159 are highly depleted yet appear to be highly oxidized (e.g. QFM+4). As a first step in attempting to unravel petrologic complexities that influence (f)O2 [oxygen fugacity] in martian magmas, this study explores the effect of (f)O2 [oxygen fugacity] on the liquid line of descent (LLD) for a primitive shergottite liquid composition (Y98). The results of this study will provide a fundamental basis for reconstructing the record of (f)O2 [oxygen fugacity] in shergottites and other martian basalts, its effect on both mineral chemistries and valence state partitioning, and a means for examining the role of crystallization (and other more complex processes) on the petrologic linkages between olivine-phyric and pyroxene-plagioclase shergottites.

  7. FoTotoro

    OpenAIRE

    Valenzuela Bandín, Fernando de

    2014-01-01

    FoTotoro es una obra gráfica de integración, en la que se mezcla la fotografía y las imágenes CG (Computer Graphics) para reconstruir uno de los momentos más icónicos de la película de animación "Mi vecino Totoro". Con este proyecto se pretende lograr una obra de calidad mezclando estos dos recursos multimedia y crear una visión personal del autor de la obra de Hayao Miyazaki "Mi vecino Totoro". FoTotoro és una obra gràfica d'integració, en la qual es barreja la fotografia i les imatges CG...

  8. Simplified, rapid, and inexpensive estimation of water primary productivity based on chlorophyll fluorescence parameter Fo.

    Science.gov (United States)

    Chen, Hui; Zhou, Wei; Chen, Weixian; Xie, Wei; Jiang, Liping; Liang, Qinlang; Huang, Mingjun; Wu, Zongwen; Wang, Qiang

    2017-04-01

    Primary productivity in water environment relies on the photosynthetic production of microalgae. Chlorophyll fluorescence is widely used to detect the growth status and photosynthetic efficiency of microalgae. In this study, a method was established to determine the Chl a content, cell density of microalgae, and water primary productivity by measuring chlorophyll fluorescence parameter Fo. A significant linear relationship between chlorophyll fluorescence parameter Fo and Chl a content of microalgae, as well as between Fo and cell density, was observed under pure-culture conditions. Furthermore, water samples collected from natural aquaculture ponds were used to validate the correlation between Fo and water primary productivity, which is closely related to Chl a content in water. Thus, for a given pure culture of microalgae or phytoplankton (mainly microalgae) in aquaculture ponds or other natural ponds for which the relationship between the Fo value and Chl a content or cell density could be established, Chl a content or cell density could be determined by measuring the Fo value, thereby making it possible to calculate the water primary productivity. It is believed that this method can provide a convenient way of efficiently estimating the primary productivity in natural aquaculture ponds and bringing economic value in limnetic ecology assessment, as well as in algal bloom monitoring. Copyright © 2017 Elsevier GmbH. All rights reserved.

  9. Development of a Complex Geometry Standard Fixture and Solvent Evaluation Method fo Assessing Replacement Solvents for AK-225G Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The focus of this analysis was the development of a complex geometry test fixture and test method for determining solvent cleaning efficiency. AK-225 belongs to a...

  10. GRACE-FO accelerometers and data processing

    Science.gov (United States)

    Lebat, V.; Boulanger, D.; Christophe, B.; Foulon, B.; Liorzou, F.; Huynh, P. A.

    2017-12-01

    The GRACE FO mission, led by the JPL (Jet Propulsion Laboratory) and GFZ (GeoForschungsZentrum), is an Earth-orbiting gravity mission, continuation of the GRACE mission, which will produce an accurate model of the Earth's gravity field variation providing global climatic data during five years at least. Firstly, the poster will present the status of GRACE-FO accelerometers: the 3 first flight models were delivered during 2016 and the schedule of the last spare flight model under manufacturing will be presented. Secondly, we will focus on data processing which can be performed at ONERA, based on the experience acquired through the MICROSCOPE mission. Through a physical model of the accelerometer and on-ground or flight calibration of the thermal sensitivity, it would be possible to improve the science return. Methods of detection and suppression of twangs have been developed for MICROSCOPE and can be applied also for GRACE-FO.

  11. Osmotically and thermally isolated forward osmosis-membrane distillation (fo-md) integrated module for water treatment applications

    KAUST Repository

    Ghaffour, Noreddine

    2016-09-01

    An integrated forward osmosis-membrane distillation (FO-MD) module and systems and methods incorporating the module is disclosed providing higher efficiencies and using less energy. The FO-MD module is osmotically and thermally isolated. The isolation can prevent mixing of FO draw solution/FO permeate and MD feed, and minimize dilution of FO draw solution and cooling of MD feed. The module provides MD feed solution and FO draw solution streams that flow in the same module but are separated by an isolation barrier. The osmotically and thermally isolated FO-MD integrated module, systems and methods offer higher driving forces of both FO and MD processes, higher recovery, and wider application than previously proposed hybrid FO- MD systems.

  12. FoAM Kernow Activity Report 2016

    OpenAIRE

    Griffiths, Amber; Griffiths, David

    2016-01-01

    This review shows selected projects from the FoAM Kernow studio in 2016. FoAM is a network of transdisciplinary labs at the intersection of art, science, nature and everyday life. FoAM’s members are generalists - people who work across disparate fields in an entangled, speculative culture. Research and creative projects at FoAM combine elements of futurecrafting, citizen science, prototyping, experience design and process facilitation to re-imagine possible futures, and artistic experime...

  13. FoAM Kernow Activity Report 2017

    OpenAIRE

    Griffiths, Amber; Weatherill, Aidan; Griffiths, David

    2017-01-01

    This review shows selected projects from the FoAM Kernow studio in 2017. FoAM is a network of transdisciplinary labs at the intersection of art, science, nature and everyday life. FoAM’s members are generalists - people who work across disparate fields in an entangled, speculative culture. Research and creative projects at FoAM combine elements of futurecrafting, citizen science, prototyping, experience design and process facilitation to re-imagine possible futures.

  14. Geomagnetic control of the midlatitude foF1 and foF2 long-term variations: Recent observations in Europe

    Science.gov (United States)

    Perrone, L.; Mikhailov, A. V.

    2016-07-01

    A new very simple method, allowing an easy control, has been applied to extract long-term (11 year) δfoF2 11y and δfoF1 11y variations from June foF2 and foF1 monthly median observations at European Slough/Chilton and Juliusruh stations, including recent data until 2015. The aim of the analysis was to check the validity of the geomagnetic control of foF2 and foF1 long-term variations in the 21st century with the main accent on the period including the last deep solar minimum in 2008-2009. The geomagnetic control was shown to be valid. Moreover, the dependence on geomagnetic activity has become more pronounced and explicit after 1990. A simultaneous analysis of foF2 and foF1 long-term variations improves the reliability of the obtained conclusions and helps understand the physical mechanism of these variations. Due to common neutral composition and the similarity of photochemical processes noontime foF2 and foF1 demonstrate similar long-term variations: the correlation coefficient between δfoF2 11y and δfoF1 11y is 0.834 at Slough/Chilton and 0.884 at Juliusruh with the 99% confidence level according to Fisher's F criterion. Midnight long-term δfoF2 11y variations also manifest a pronounced dependence on Ap11y which may be interpreted in the framework of the geomagnetic control concept.

  15. Analytical methods under emergency conditions

    International Nuclear Information System (INIS)

    Sedlet, J.

    1983-01-01

    This lecture discusses methods for the radiochemical determination of internal contamination of the body under emergency conditions, here defined as a situation in which results on internal radioactive contamination are needed quickly. The purpose of speed is to determine the necessity for medical treatment to increase the natural elimination rate. Analytical methods discussed include whole-body counting, organ counting, wound monitoring, and excreta analysis. 12 references

  16. Treatment of Medical Radioactive Liquid Waste Using Forward Osmosis (FO) Membrane Process

    KAUST Repository

    Lee, Songbok

    2018-04-07

    The use of forward osmosis (FO) for concentrating radioactive liquid waste from radiation therapy rooms in hospitals was systematically investigated in this study. The removal of natural and radioactive iodine using FO was first investigated with varying pHs and draw solutions (DSs) to identify the optimal conditions for FO concentration. Results showed that FO had a successful rejection rate for both natural and radioactive iodine (125I) of up to 99.3%. This high rejection rate was achieved at a high pH, mainly due to electric repulsion between iodine and membrane. Higher iodine removal by FO was also attained with a DS that exhibits a reverse salt flux (RSF) adequate to hinder iodine transport. Following this, actual radioactive medical liquid waste was collected and concentrated using FO under these optimal conditions. The radionuclides in the medical waste (131I) were removed effectively, but the water recovery rate was limited due to severe membrane fouling. To enhance the recovery rate, hydraulic washing was applied, but this had only limited success due to combined organic-inorganic fouling of the FO membrane. Finally, the effect of FO concentration on the reduction of septic tank volume was simulated as a function of recovery rate. To our knowledge, this study is the first attempt to explore the potential of FO technology for treating radioactive waste, and thus could be expanded to the dewatering of the radioactive liquid wastes from a variety of sources, such as nuclear power plants.

  17. The Danish FoU Programme

    DEFF Research Database (Denmark)

    Magnussen, Lisbeth; Gottlieb, Susanne; Maaløe, Inger

    I 1999 modtog det danske erhvervsuddannelsessystem Bertelsmann Prisen for dets innovative kapacitet. En af de vigtigste faktorer for den kontinuerlige fornyelse af det danske erhvervsuddannelsessystem er det danske Forsøgs- og Udviklingsprogram (FoU). Publikationen beskriver det danske FoU progra...

  18. Students' Social Media Engagement and Fear of Missing out (FoMO) in a Diverse Classroom

    Science.gov (United States)

    Alt, Dorit

    2017-01-01

    With the growing attention paid to fear of missing out (FoMO) psychological phenomenon in explaining social media engagement (SME), this mixed-method research measured the relative impact of FoMO on students' SME for personal reasons during lectures. The moderating effect of culture (minority vs. non-minority students) on the connection between…

  19. Dario Fo irvitused Sadamateatris / Riho Laurisaar

    Index Scriptorium Estoniae

    Laurisaar, Riho

    2006-01-01

    Dario Fo "Müsteerium buff" Tartu Sadamateatris Viljandi Kultuuriakadeemia teatrikunsti õppetooli kolmanda kursuse ehk kuuenda lennu tudengite esituses. Näitemängu on lavastanud Peeter Raudsepp. Esietendus 25. apr

  20. Efficient Training Methods for Conditional Random Fields

    National Research Council Canada - National Science Library

    Sutton, Charles A

    2008-01-01

    .... In this thesis, I investigate efficient training methods for conditional random fields with complex graphical structure, focusing on local methods which avoid propagating information globally along the graph...

  1. Long-term trends in foF2: their estimating and origin

    Directory of Open Access Journals (Sweden)

    W. Wan

    2008-03-01

    Full Text Available This paper deals with two problems, methods of foF2 trend determination and origin of trends in foF2, both being controversial in current literature. We found that various regression-based methods and artificial neural network-based method of Yue et al. (2006 provided comparable results within uncertainties caused mainly by various ways of removing/suppressing the dominant solar cycle effect. The role of geomagnetic activity in the observed trends in foF2 was probably substantial and might be still even rather dominant in the last quarter of the 20th century.

  2. Ferric and cobaltous hydroacid complexes for forward osmosis (FO) processes

    KAUST Repository

    Ge, Qingchun

    2014-07-01

    Cupric and ferric hydroacid complexes have proven their advantages as draw solutes in forward osmosis in terms of high water fluxes, negligible reverse solute fluxes and easy recovery (Ge and Chung, 2013. Hydroacid complexes: A new class of draw solutes to promote forward osmosis (FO) processes. Chemical Communications 49, 8471-8473.). In this study, cobaltous hydroacid complexes were explored as draw solutes and compared with the ferric hydroacid complex to study the factors influencing their FO performance. The solutions of the cobaltous complexes produce high osmotic pressures due to the presence of abundant hydrophilic groups. These solutes are able to dissociate and form a multi-charged anion and Na+ cations in water. In addition, these complexes have expanded structures which lead to negligible reverse solute fluxes and provide relatively easy approaches in regeneration. These characteristics make the newly synthesized cobaltous complexes appropriate as draw solutes. The FO performance of the cobaltous and ferric-citric acid (Fe-CA) complexes were evaluated respectively through cellulose acetate membranes, thin-film composite membranes fabricated on polyethersulfone supports (referred as TFC-PES), and polybenzimidazole and PES dual-layer (referred as PBI/PES) hollow fiber membranes. Under the conditions of DI water as the feed and facing the support layer of TFC-PES FO membranes (PRO mode), draw solutions at 2.0M produced relatively high water fluxes of 39-48 LMH (Lm-2hr-1) with negligible reverse solute fluxes. A water flux of 17.4 LMH was achieved when model seawater of 3.5wt.% NaCl replaced DI water as the feed and 2.0M Fe-CA as the draw solution under the same conditions. The performance of these hydroacid complexes surpasses those of the synthetic draw solutes developed in recent years. This observation, along with the relatively easy regeneration, makes these complexes very promising as a novel class of draw solutes. © 2014 Elsevier Ltd.

  3. Investigation of the relationship between ionospheric foF2 and earthquakes

    Science.gov (United States)

    Karaboga, Tuba; Canyilmaz, Murat; Ozcan, Osman

    2018-04-01

    Variations of the ionospheric F2 region critical frequency (foF2) have been investigated statistically before earthquakes during 1980-2008 periods in Japan area. Ionosonde data was taken from Kokubunji station which is in the earthquake preparation zone for all earthquakes. Standard Deviations and Inter-Quartile Range methods are applied to the foF2 data. It is observed that there are anomalous variations in foF2 before earthquakes. These variations can be regarded as ionospheric precursors and may be used for earthquake prediction.

  4. Dario Fo and the dramaturgy of irreverence

    African Journals Online (AJOL)

    Although fascinated by Commedia dell'arte in general and by the colourful figure of Harlequin in particular, Fo's favoured model is the medieval giullare. The giullare is a figure from. Italian history, and it is not easy to find the exact equivalent in. English. Etymologically, the word is associated with 'juggler', but the English ...

  5. Statistical Methods for Conditional Survival Analysis.

    Science.gov (United States)

    Jung, Sin-Ho; Lee, Ho Yun; Chow, Shein-Chung

    2017-11-29

    We investigate the survival distribution of the patients who have survived over a certain time period. This is called a conditional survival distribution. In this paper, we show that one-sample estimation, two-sample comparison and regression analysis of conditional survival distributions can be conducted using the regular methods for unconditional survival distributions that are provided by the standard statistical software, such as SAS and SPSS. We conduct extensive simulations to evaluate the finite sample property of these conditional survival analysis methods. We illustrate these methods with real clinical data.

  6. Partitioning of platinum-group elements (PGE) and chalcogens (Se, Te, As, Sb, Bi) between monosulfide-solid solution (MSS), intermediate solid solution (ISS) and sulfide liquid at controlled fO2-fS2 conditions

    Science.gov (United States)

    Liu, Yanan; Brenan, James

    2015-06-01

    In order to better understand the behavior of highly siderophile elements (HSEs: Os, Ir, Ru, Rh, Pt, Pd, Au, Re), Ag, Pb and chalcogens (As, Se, Sb, Te and Bi) during the solidification of sulfide magmas, we have conducted a series of experiments to measure partition coefficients (D values) between monosulfide solid solution (MSS) and sulfide melt, as well as MSS and intermediate solid solution (ISS), at 0.1 MPa and 860-926 °C, log fS2 -3.0 to -2.2 (similar to the Pt-PtS buffer), with fO2 controlled at the fayalite-magnetite-quartz (FMQ) buffer. The IPGEs (Os, Ir, Ru), Rh and Re are found to be compatible in MSS relative to sulfide melt with D values ranging from ∼20 to ∼5, and DRe/DOs of ∼0.5. Pd, Pt, Au, Ag, Pb, as well as the chalcogens, are incompatible in MSS, with D values ranging from ∼0.1 to ∼1 × 10-3. For the same metal/sulfur ratio, D values for the IPGEs, Rh and Re are systematically larger than most past studies, correlating with higher oxygen content in the sulfide liquid, reflecting the significant effect of oxygen on increasing the activity coefficients for these elements in the melt phase. MSS/ISS partitioning experiments reveal that Ru, Os, Ir, Rh and Re are partitioned into MSS by a factor of >50, whereas Pd, Pt, Ag, Au and the chalcogens partition from weakly (Se, As) to strongly (Ag, Au) into ISS. Uniformly low MSS- and ISS- melt partition coefficients for the chalcogens, Pt, Pd, Ag and Au will lead to enrichment in the residual sulfide liquid, but D values are generally too large to reach early saturation in Pt-Pd-chalcogen-rich accessory minerals, based on current solubility estimates. Instead, these phases likely precipitate at the last dregs of crystallization. Modeled evolution curves for the PGEs and chalcogens are in reasonably good agreement with whole-rock sulfide compositions for the McCreedy East deposit (Sudbury, Ontario), consistent with an origin by crystallization of MSS, then MSS + ISS from sulfide magma.

  7. Gas sensing method applicable to real conditions

    Science.gov (United States)

    Szczurek, A.; Maciejewska, M.

    2013-04-01

    In this work, we tested the influence of various sampling techniques and modes of operation on the response of sensor systems under real conditions. The first system was based on diffusive sampling. The second one used a dynamic method of sampling. In the third system, a stop flow mode of operation was applied. A considerable error of target gas concentration assessment was obtained in the first two cases. The error resulted from sensor signal fluctuations encountered during their exposure either to the air at the measurement point (diffusive sampling) or to the air drawn from the measurement point (dynamic sampling). The fluctuations could be attributed to the temporal variation of physical and chemical parameters of air. The main merit of the third method consists in utilizing sensor exposure under the conditions of stopped flow for the purpose of pollutant concentration assessment. While using this method, the accuracy of target gas quantification under real conditions was comparable to the one achieved when measuring standard gases. We think that the proposed method is a valuable contribution, which addresses the increasing demand for sensor systems that perform quantitative pollution assessment in workplace air, under real conditions. This paper was presented at the Conference on Optoelectronic and Electronic Sensors held in Karpacz, Poland, on 24-27 June 2012.

  8. Enhancing boron rejection in FO using alkaline draw solutions.

    Science.gov (United States)

    Wang, Yi-Ning; Li, Weiyi; Wang, Rong; Tang, Chuyang Y

    2017-07-01

    This study provides a novel method to enhance boron removal in a forward osmosis (FO) process. It utilizes the reverse solute diffusion (RSD) of ions from alkaline draw solutions (DSs) and the concentration polarization of the hydroxyl ions to create a highly alkaline environment near the membrane active surface. The results show that boron rejection can be significantly enhanced by increasing the pH of NaCl DS to 12.5 in the active-layer-facing-feed-solution (AL-FS) orientation. The effect of RSD enhanced boron rejection was further promoted in the presence of concentration polarization (e.g., in the active-layer-facing-draw-solution (AL-DS) orientation). The current study opens a new dimension for controlling contaminant removal by FO using tailored DS chemistry, where the RSD-induced localized water chemistry change is taken advantage in contrast to the conventional method of chemical dosing to the bulk feed water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Lorenzo Foà (1937 - 2014)

    CERN Multimedia

    2014-01-01

    Lorenzo Foà, a protagonist of Experimental High Energy Physics for five decades and mentor of dozens of students, passed away peacefully and unexpectedly in Pisa on 13 January 2014. He was a professor at the Scuola Normale Superiore in Pisa and spent most of his scientific career at CERN.   Lorenzo Foà (left) in front of the ALEPH detector, 2001. He is photographed with Jack Steinberger (centre) and Pierre Lazeyras (right). In the early 1960s Lorenzo was among the proponents of two experiments that allowed the first measurements of π0 and η lifetimes via the Primakoff effect at Frascati and then at DESY. Later he joined the CERN-Orsay-Pisa Collaboration, studying polarisation in hadron scattering, and then the Pisa-Stony Brook Collaboration at the CERN ISR. This experiment discovered that the total proton-proton cross section starts increasing at ISR energies, a departure from what had previously appeared to be a flat “asymptotic” beha...

  10. Methods of conditioning direct methanol fuel cells

    Science.gov (United States)

    Rice, Cynthia; Ren, Xiaoming; Gottesfeld, Shimshon

    2005-11-08

    Methods for conditioning the membrane electrode assembly of a direct methanol fuel cell ("DMFC") are disclosed. In a first method, an electrical current of polarity opposite to that used in a functioning direct methanol fuel cell is passed through the anode surface of the membrane electrode assembly. In a second method, methanol is supplied to an anode surface of the membrane electrode assembly, allowed to cross over the polymer electrolyte membrane of the membrane electrode assembly to a cathode surface of the membrane electrode assembly, and an electrical current of polarity opposite to that in a functioning direct methanol fuel cell is drawn through the membrane electrode assembly, wherein methanol is oxidized at the cathode surface of the membrane electrode assembly while the catalyst on the anode surface is reduced. Surface oxides on the direct methanol fuel cell anode catalyst of the membrane electrode assembly are thereby reduced.

  11. Hybrid SBR–FO system for wastewater treatment and reuse: Operation, fouling and cleaning

    KAUST Repository

    Valladares Linares, Rodrigo

    2016-04-05

    Forward osmosis (FO) is a novel membrane separation process that potentially can be used as an energy-saving alternative to conventional membrane processes. A hybrid sequential batch reactor (SBR)–FO process was explored. In this system, a plate and frame FO cell including two flat-sheet FO membranes was submerged in a bioreactor treating synthetic domestic wastewater. The dissolved organic carbon (DOC) removal efficiency of the system was 98.55%. Total nitrogen removal was 62.4%, with nitrate, nitrite and ammonium removals of 58.4%, 96.2% and 88.4%, respectively. Phosphate removal was almost 100%. The 15-hour cycle average water flux of a virgin membrane with air scouring was 2.95 L/m2·h− 1. Air scouring can help to remove loose foulants from the membrane active layer, thus helping to recover up to 89.5% of the original flux. Chemical cleaning of the fouled active layer of the FO membrane was not as effective as air scouring. Natural organic matter (NOM) characterization methods (liquid chromatography–organic carbon detection (LC–OCD) and 3-D fluorescence excitation emission matrix (FEEM)) show that the FO membrane has a very good performance in rejecting biopolymers, humics and building blocks, but a limited ability in rejecting low molecular weight neutrals. Transparent exopolymer particles (TEP) and other biopolymers might be associated with fouling of the membrane on the support layer. A 1% sodium hypochlorite (NaOCl) cleaning solution was proved to be effective for removing the foulants from the support layer and recovering the original flux.

  12. Social Media Use and the Fear of Missing out (FoMO) While Studying Abroad

    Science.gov (United States)

    Hetz, Patricia R.; Dawson, Christi L.; Cullen, Theresa A.

    2015-01-01

    Fear of Missing Out (FoMO) is a social construct that examines whether students are concerned that they are missing out on experiences that others are having, and we examined this relation to their concerns over missing activities in their home culture. This mixed-methods pilot study sought to determine how social media affects the study abroad…

  13. The disappearance and reformation of the accretion disc during a low state of FO Aquarii

    Science.gov (United States)

    Hameury, J.-M.; Lasota, J.-P.

    2017-09-01

    Context. FO Aquarii, an asynchronous magnetic cataclysmic variable (intermediate polar) went into a low state in 2016, from which it slowly and steadily recovered without showing dwarf nova outbursts. This requires explanation since in a low state, the mass-transfer rate is in principle too low for the disc to be fully ionised and the disc should be subject to the standard thermal and viscous instability observed in dwarf novae. Aims: We investigate the conditions under which an accretion disc in an intermediate polar could exhibit a luminosity drop of two magnitudes in the optical band without showing outbursts. Methods: We use our numerical code for the time evolution of accretion discs, including other light sources from the system (primary, secondary, hot spot). Results: We show that although it is marginally possible for the accretion disc in the low state to stay on the hot stable branch, the required mass-transfer rate in the normal state would then have to be extremely high, of the order of 1019 g s-1 or even larger. This would make the system so intrinsically bright that its distance should be much larger than allowed by all estimates. We show that observations of FO Aqr are well accounted for by the same mechanism that we have suggested as explaining the absence of outbursts during low states of VY Scl stars: during the decay, the magnetospheric radius exceeds the circularisation radius, so that the disc disappears before it enters the instability strip for dwarf nova outbursts. Conclusions: Our results are unaffected, and even reinforced, if accretion proceeds both via the accretion disc and directly via the stream during some intermediate stages; the detailed process through which the disc disappears still requires investigation.

  14. Different Methods for Conditioning Chloride Salt Wastes

    International Nuclear Information System (INIS)

    De Angelis, G.; Fedeli, C.; Capone, M.; Marzo, G.A.; Mariani, M.; Da Ros, M.; Giacobbo, F.; Macerata, E.; Giola, M.

    2015-01-01

    Three different methods have been used to condition chloride salt wastes coming from pyro-processes. Two of them allow to synthesise sodalite, a naturally occurring mineral containing chlorine: the former, starting from Zeolite 4A, which transforms the zeolite into sodalite; the latter, which starts from kaolinite, giving sodalite as well. In addition, a new matrix, termed SAP (SiO 2 -Al 2 O 3 -P 2 O 5 ), has been synthesised. It is able to form different mineral phases which occlude fission metals. The products from the different processes have been fully characterised. In particular the chemical durability of the final waste forms has been determined using the standard product consistency test. According to the results obtained, SAP seems to be a promising matrix for the incorporation of chloride salt wastes from pyro-processes. Financial support from the Nuclear Fission Safety Programme of the European Union (projects ACSEPT, contract FP7-CP-2007- 211 267, and SACSESS, Collaborative Project 323282), as well as from Italian Ministry for Economic Development (Accordo di Programma: Piano Annuale di Realizzazione 2008-2009) is gratefully acknowledged. (authors)

  15. Empirical methods for estimating future climatic conditions

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    Applying the empirical approach permits the derivation of estimates of the future climate that are nearly independent of conclusions based on theoretical (model) estimates. This creates an opportunity to compare these results with those derived from the model simulations of the forthcoming changes in climate, thus increasing confidence in areas of agreement and focusing research attention on areas of disagreements. The premise underlying this approach for predicting anthropogenic climate change is based on associating the conditions of the climatic optimums of the Holocene, Eemian, and Pliocene with corresponding stages of the projected increase of mean global surface air temperature. Provided that certain assumptions are fulfilled in matching the value of the increased mean temperature for a certain epoch with the model-projected change in global mean temperature in the future, the empirical approach suggests that relationships leading to the regional variations in air temperature and other meteorological elements could be deduced and interpreted based on use of empirical data describing climatic conditions for past warm epochs. Considerable care must be taken, of course, in making use of these spatial relationships, especially in accounting for possible large-scale differences that might, in some cases, result from different factors contributing to past climate changes than future changes and, in other cases, might result from the possible influences of changes in orography and geography on regional climatic conditions over time

  16. SeFo: A Package for Generating Probabilistic Forecasts from NMME Predictive Ensembles

    Directory of Open Access Journals (Sweden)

    Nir Y Krakauer

    2016-05-01

    Full Text Available Long-range weather forecasts based on output from ensembles of computer simulations are attracting increasing interest. A variety of methods have been proposed to convert the ensemble outputs to calibrated probabilistic forecasts. The package presented here (SeFo, for Seasonal Forecasting implements a number of methods for producing forecasts of monthly surface air temperature anomalies up to 9 months in advance using output from the North American Multi-Model Ensemble (NMME. The package contains modules for downloading and reading past observations and ensemble output; producing forecast probability distributions; and verifying and calibrating a user-determined subset of methods using arbitrary past periods. By changing individual modules, the package could be extended to use other model ensembles, forecast other weather variables, or apply other forecast methods. SeFo is written in the numerical computing language Octave and is available on Bitbucket under the GNU General Public License (Version 3 or later.

  17. Detection of viability: radiopharmacological conditions, methods, indications

    International Nuclear Information System (INIS)

    Krause, T.; Moser, E.

    1996-01-01

    The indication of revascularization in patients with coronary artery disease is mainly based on factors such as coronary anatomy ischemia as well as ventricular function, patient's biological age or accompanying diseases. In general, evidence of vital myocardium plays a secondary role but will be important in patients with hibernating myocardium. Tl-201 scintigraphy with re-injection technique or rest-redistribution-examination is a simple and cost-effective method of the detection or exclusion of hibernation. However, in case of doubt F-18 FDG PET is recommended to guide further therapeutic strategies. (orig.) [de

  18. LISA Experience from GRACE-FO Optical Payload (LEGOP)

    Science.gov (United States)

    McKenzie, Kirk

    We propose to develop in-flight tests of high-risk elements of laser interferometry for gravitational wave astronomy missions, such as the Laser Interferometer Space Antenna (LISA) mission, for deployment on the GRACE-FO mission. The proposed set of experiments, LISA Experience from GRACE-FO Optical Payload (LEGOP), exploits the similarities between the LISA and GRACE-FO optical links to use GRACE-FO as a "mission of opportunity" for demonstration of high-risk and innovative technologies for the LISA mission. We will develop FPGA algorithms for the tests and perform laboratory experiments and hardware-in-the-loop simulations to verify them. Specifically, we will target the following aspects of LISA inter-spacecraft interferometry: 1. Absolute optical-ranging and Time Delay Interferometry (TDI). TDI is the process used on LISA to combine one-way inter-spacecraft measurements to form synthesized interferometers, such as the Michelson interferometer, that are free of laser frequency noise, but retain the gravitational wave signal. The one-way measurements must be combined with precise delays, proportional to the light travel time between spacecraft (the range) and difference of on board clocks. The proposed in-flight experiment would see a LISA like optical ranging system deployed to provide the required delays for a TDI experiment on GRACE-FO. We will develop the FPGA code required for this experiment and perform validation of this optical-ranging system for GRACE-FO through a TDI experiment on the JPL LISA interferometer testbed. 2. Arm-locking: A technique for transferring the stability of the spacecraft separation to the laser frequency. Because arm-locking uses the LISA arms, the best frequency reference available, it offers unparalleled stability and requires no additional flight hardware. It cannot be demonstrated experimentally in a LISA-like environment on Earth. An in-flight demonstration of arm-locking would validate the operation of arm- locking, enabling

  19. Validation of foF2 and TEC Modeling During Geomagnetic Disturbed Times: Preliminary Outcomes of International Forum for Space Weather Modeling Capabilities Assessment

    Science.gov (United States)

    Shim, J. S.; Tsagouri, I.; Goncharenko, L. P.; Kuznetsova, M. M.

    2017-12-01

    To address challenges of assessment of space weather modeling capabilities, the CCMC (Community Coordinated Modeling Center) is leading the newly established "International Forum for Space Weather Modeling Capabilities Assessment." This presentation will focus on preliminary outcomes of the International Forum on validation of modeled foF2 and TEC during geomagnetic storms. We investigate the ionospheric response to 2013 Mar. geomagnetic storm event using ionosonde and GPS TEC observations in North American and European sectors. To quantify storm impacts on foF2 and TEC, we first quantify quiet-time variations of foF2 and TEC (e.g., the median and the average of the five quietest days for the 30 days during quiet conditions). It appears that the quiet time variation of foF2 and TEC are about 10% and 20-30%, respectively. Therefore, to quantify storm impact, we focus on foF2 and TEC changes during the storm main phase larger than 20% and 50%, respectively, compared to 30-day median. We find that in European sector, both foF2 and TEC response to the storm are mainly positive phase with foF2 increase of up to 100% and TEC increase of 150%. In North America sector, however, foF2 shows negative effects (up to about 50% decrease), while TEC shows positive response (the largest increase is about 200%). To assess modeling capability of reproducing the changes of foF2 and TEC due to the storm, we use various model simulations, which are obtained from empirical, physics-based, and data assimilation models. The performance of each model depends on the selected metrics, therefore, only one metrics is not enough to evaluate the models' predictive capabilities in capturing the storm impact. The performance of the model also varies with latitude and longitude.

  20. Concentrating molasses distillery wastewater using biomimetic forward osmosis (FO) membranes

    DEFF Research Database (Denmark)

    Singh, N.; Petrinic, I.; Hélix-Nielsen, Claus

    2018-01-01

    . This work examines the concentration of distillery wastewater by forward osmosis (FO) using aquaporin biomimetic membranes and magnesium chloride hexahydrate (MgCl2.6H2O) as draw solution. The operational parameters viz. feed solution and draw solution flow rate and draw solution concentration were...

  1. NOM and TEP fouling of a forward osmosis (FO) membrane: Foulant identification and cleaning

    KAUST Repository

    Valladares Linares, Rodrigo

    2012-12-01

    The study of forward osmosis (FO) membranes has increased due to the already demonstrated advantages compared to high-energy membrane processes such as reverse osmosis (RO). This research focuses on characterization of the natural organic matter (NOM) fraction causing fouling on the active layer (AL) of a FO membrane in a novel plate and frame module configuration, facing secondary wastewater effluent as a feed solution (FS) and seawater used as a draw solution (DS). In addition, transparent exopolymer particles (TEP) were observed on the support layer (SL) of the membrane in contact with the DS. The NOM fouling layer, after characterizing the water samples and membranes used, was found to be composed of biopolymers and protein-like substances, which adversely affect the flux of water through the FO membrane. However, NOM fouling showed high reversibility, up to 90% when air scouring for 15. min is used as a cleaning technique. The irreversible fouling in this work was found to be 8.2% after chemical cleaning. On the support layer of the membrane, TEP formed clusters clearly identifiable with an optical microscope and a TEP-specific dye. Chemical cleaning with 1% NaOCl for 10. min proved to be the most effective method to remove TEP. © 2012.

  2. Parametric decadal climate forecast recalibration (DeFoReSt 1.0)

    Science.gov (United States)

    Pasternack, Alexander; Bhend, Jonas; Liniger, Mark A.; Rust, Henning W.; Müller, Wolfgang A.; Ulbrich, Uwe

    2018-01-01

    Near-term climate predictions such as decadal climate forecasts are increasingly being used to guide adaptation measures. For near-term probabilistic predictions to be useful, systematic errors of the forecasting systems have to be corrected. While methods for the calibration of probabilistic forecasts are readily available, these have to be adapted to the specifics of decadal climate forecasts including the long time horizon of decadal climate forecasts, lead-time-dependent systematic errors (drift) and the errors in the representation of long-term changes and variability. These features are compounded by small ensemble sizes to describe forecast uncertainty and a relatively short period for which typically pairs of reforecasts and observations are available to estimate calibration parameters. We introduce the Decadal Climate Forecast Recalibration Strategy (DeFoReSt), a parametric approach to recalibrate decadal ensemble forecasts that takes the above specifics into account. DeFoReSt optimizes forecast quality as measured by the continuous ranked probability score (CRPS). Using a toy model to generate synthetic forecast observation pairs, we demonstrate the positive effect on forecast quality in situations with pronounced and limited predictability. Finally, we apply DeFoReSt to decadal surface temperature forecasts from the MiKlip prototype system and find consistent, and sometimes considerable, improvements in forecast quality compared with a simple calibration of the lead-time-dependent systematic errors.

  3. Application of Ultrasonic Sensors in Road Surface Condition Distinction Methods

    Directory of Open Access Journals (Sweden)

    Shota Nakashima

    2016-10-01

    Full Text Available The number of accidents involving elderly individuals has been increasing with the increase of the aging population, posing increasingly serious challenges. Most accidents are caused by reduced judgment and physical abilities, which lead to severe consequences. Therefore, studies on support systems for elderly and visually impaired people to improve the safety and quality of daily life are attracting considerable attention. In this study, a road surface condition distinction method using reflection intensities obtained by an ultrasonic sensor was proposed. The proposed method was applied to movement support systems for elderly and visually impaired individuals to detect dangerous road surfaces and give an alarm. The method did not perform well in previous studies of puddle detection, because the alert provided by the method did not enable users to avoid puddles. This study extended the method proposed by previous studies with respect to puddle detection ability. The findings indicate the effectiveness of the proposed method by considering four road surface conditions. The proposed method could detect puddle conditions. The effectiveness of the proposed method was verified in all four conditions, since users could differentiate between road surface conditions and classify the conditions as either safe or dangerous.

  4. CONDITIONING METHODS FOR ANIMALS IN AGRICULTURE: A REVIEW

    OpenAIRE

    Abramson, Charles Ira; Kieson, Emily

    2016-01-01

    Abstract This article briefly describes different conditioning techniques used to help understand learning in farm livestock and economically important animals. A basic overview of conditioning is included along with the importance of different conditioning methods, associative and non-associative learning, and how these principles apply to chickens, horses, cows, goats, pigs, and sheep. Additional information on learning theory specific for each animal is also provided. Resumo Este artigo...

  5. What is next for forward osmosis (FO) and pressure retarded osmosis (PRO)

    KAUST Repository

    Chung, Neal Tai-Shung

    2015-10-29

    This short review summarizes our understanding and perspectives on FO and PRO processes and meaningful R & D in order to develop effective and sustainable FO and PRO technologies for water reuse and osmotic power generation.

  6. The grazing index method of range condition assessment | du Toit ...

    African Journals Online (AJOL)

    Owing to the difficulty of examining succession theory in the Karoo, it is suggested the ecological index method (EIM), be replaced by the grazing index method (GIM), through the introduction of grazing index values (GIV) for Karoo plant species. The GIM may provide more acceptable range condition scores and more ...

  7. Cleaning protocol for a FO membrane fouled in wastewater reuse

    KAUST Repository

    Valladares Linares, Rodrigo

    2013-05-30

    Forward osmosis (FO) is an emerging technology which can be applied in water reuse applications. Osmosis is a natural process that involves less energy consumption than reverse osmosis (RO), and therefore can be applied as a dilution process before low-pressure RO; it is expected to compete favourably against current advanced water reuse technologies that use microfiltration/ultrafiltration and RO. The focus of this research was to assess the efficiency of different cleaning procedures to remove fouling from the surface of a FO membrane during the operation of a submerged system working in FO-mode (active layer (AL) facing feed solution) intended for secondary wastewater effluent (SWWE) recovery, using seawater as draw solution (DS), which will be diluted and can further be fed to a low-pressure RO unit to produce fresh water. Natural organic matter (NOM) fouling was expected to affect the AL, while for the support layer (SL), transparent exopolymer particles (TEP) were used as indicators of fouling due to their stickiness and propensity to enhance the attachment of other foulants in seawater on the membrane surface. The composition of the NOM fouling layer was determined after proper characterisation with a liquid chromatograph coupled with organic carbon detection (LC-OCD), showing biopolymers and protein-like substances as the main constituents. NOM fouling showed high hydraulic reversibility after a 25% flux decline was observed, up to 89.5% when in situ air scouring for 15 min was used as a cleaning technique. Chemical cleaning with a mixture of Alconox, an industrial detergent containing phosphates, and sodium EDTA showed to increase the reversibility (93.6%). Osmotic backwash using a 4% NaCl solution and DI water proved to be ineffective to recover flux due to the salt diffusion phenomena occurring at the AL. Part of the flux that could not be recovered is attributable to TEP fouling on the SL, which forms clusters clearly identifiable with an optical

  8. Twitter som en kommunikationsplattform för företag : En studie om hur Twitter användare förhåller sig till företagens närvaro på Twitter

    OpenAIRE

    Blechingberg, Jessica

    2016-01-01

    Webben har förändrat förutsättningar för traditionell PR. I och med den digitala utvecklingen har sättet att presentera företagen förändrats. Sociala medier har blivit ett väsentligt arbetsredskap och utvecklingen av digital media har lett till att företag kan ”prata” mera direkt med sin målgrupp och sina kunder samt potentiella kunder. Tack vare de sociala medierna, kan företaget på nya sätt marknadsföra och kommunicera med kunden. Denna möjlighet kan även vara utmanande oc...

  9. Modeling ionospheric foF2 by using empirical orthogonal function analysis

    Science.gov (United States)

    E, A.; Zhang, D.-H.; Xiao, Z.; Hao, Y.-Q.; Ridley, A. J.; Moldwin, M.

    2011-08-01

    A similar-parameters interpolation method and an empirical orthogonal function analysis are used to construct empirical models for the ionospheric foF2 by using the observational data from three ground-based ionosonde stations in Japan which are Wakkanai (Geographic 45.4° N, 141.7° E), Kokubunji (Geographic 35.7° N, 140.1° E) and Yamagawa (Geographic 31.2° N, 130.6° E) during the years of 1971-1987. The impact of different drivers towards ionospheric foF2 can be well indicated by choosing appropriate proxies. It is shown that the missing data of original foF2 can be optimal refilled using similar-parameters method. The characteristics of base functions and associated coefficients of EOF model are analyzed. The diurnal variation of base functions can reflect the essential nature of ionospheric foF2 while the coefficients represent the long-term alteration tendency. The 1st order EOF coefficient A1 can reflect the feature of the components with solar cycle variation. A1 also contains an evident semi-annual variation component as well as a relatively weak annual fluctuation component. Both of which are not so obvious as the solar cycle variation. The 2nd order coefficient A2 contains mainly annual variation components. The 3rd order coefficient A3 and 4th order coefficient A4 contain both annual and semi-annual variation components. The seasonal variation, solar rotation oscillation and the small-scale irregularities are also included in the 4th order coefficient A4. The amplitude range and developing tendency of all these coefficients depend on the level of solar activity and geomagnetic activity. The reliability and validity of EOF model are verified by comparison with observational data and with International Reference Ionosphere (IRI). The agreement between observations and EOF model is quite well, indicating that the EOF model can reflect the major changes and the temporal distribution characteristics of the mid-latitude ionosphere of the Sea of Japan

  10. Absolute gain measurement by the image method under mismatched condition

    Science.gov (United States)

    Lee, Richard Q.; Baddour, Maurice F.

    1987-01-01

    Purcell's image method for measuring the absolute gain of an antenna is particularly attractive for small test antennas. The method is simple to use and utilizes only one antenna with a reflecting plane to provide an image for the receiving antenna. However, the method provides accurate results only if the antenna is matched to its waveguide. In this paper, a waveguide junction analysis is developed to determine the gain of an antenna under mismatched condition. Absolute gain measurements for two standard gain horn antennas have been carried out. Experimental results agree closely with published data.

  11. VNIR hyperspectral background characterization methods in adverse weather conditions

    Science.gov (United States)

    Romano, João M.; Rosario, Dalton; Roth, Luz

    2009-05-01

    Hyperspectral technology is currently being used by the military to detect regions of interest where potential targets may be located. Weather variability, however, may affect the ability for an algorithm to discriminate possible targets from background clutter. Nonetheless, different background characterization approaches may facilitate the ability for an algorithm to discriminate potential targets over a variety of weather conditions. In a previous paper, we introduced a new autonomous target size invariant background characterization process, the Autonomous Background Characterization (ABC) or also known as the Parallel Random Sampling (PRS) method, features a random sampling stage, a parallel process to mitigate the inclusion by chance of target samples into clutter background classes during random sampling; and a fusion of results at the end. In this paper, we will demonstrate how different background characterization approaches are able to improve performance of algorithms over a variety of challenging weather conditions. By using the Mahalanobis distance as the standard algorithm for this study, we compare the performance of different characterization methods such as: the global information, 2 stage global information, and our proposed method, ABC, using data that was collected under a variety of adverse weather conditions. For this study, we used ARDEC's Hyperspectral VNIR Adverse Weather data collection comprised of heavy, light, and transitional fog, light and heavy rain, and low light conditions.

  12. Upgrading CCIR's fo F 2 maps using available ionosondes and genetic algorithms

    Science.gov (United States)

    Gularte, Erika; Carpintero, Daniel D.; Jaen, Juliana

    2018-04-01

    We have developed a new approach towards a new database of the ionospheric parameter fo F 2 . This parameter, being the frequency of the maximum of the ionospheric electronic density profile and its main modeller, is of great interest not only in atmospheric studies but also in the realm of radio propagation. The current databases, generated by CCIR (Committee Consultative for Ionospheric Radiowave propagation) and URSI (International Union of Radio Science), and used by the IRI (International Reference Ionosphere) model, are based on Fourier expansions and have been built in the 60s from the available ionosondes at that time. The main goal of this work is to upgrade the databases by using new available ionosonde data. To this end we used the IRI diurnal/spherical expansions to represent the fo F 2 variability, and computed its coefficients by means of a genetic algorithm (GA). In order to test the performance of the proposed methodology, we applied it to the South American region with data obtained by RAPEAS (Red Argentina para el Estudio de la Atmósfera Superior, i.e. Argentine Network for the Study of the Upper Atmosphere) during the years 1958-2009. The new GA coefficients provide a global better fit of the IRI model to the observed fo F 2 than the CCIR coefficients. Since the same formulae and the same number of coefficients were used, the overall integrity of IRI's typical ionospheric feature representation was preserved. The best improvements with respect to CCIR are obtained at low solar activities, at large (in absolute value) modip latitudes, and at night-time. The new method is flexible in the sense that can be applied either globally or regionally. It is also very easy to recompute the coefficients when new data is available. The computation of a third set of coefficients corresponding to days of medium solar activity in order to avoid the interpolation between low and high activities is suggested. The same procedure as for fo F 2 can be perfomed to

  13. Extended Analysis of Real-Time foF2 Mapping in Mideastern China Based On Shortwave Signals

    Science.gov (United States)

    Cheng, Li; Ma, Hong; Yu, De; Li, Yang; Qin, Yong

    2017-11-01

    A method for the real-time mapping of the critical frequency of the F2 layer (foF2) is established using shortwave radio signals as the radiation sources, thereby eliminating the need for ionosonde stations, and tested in mideastern China. The ionospheric foF2 in the reflection area between the receiving station and the radio stations is obtained using a probabilistic inversion method. Subsequently, Kriging is used for the real-time foF2 mapping. To heighten the performance of the reconstruction, the International Reference Ionosphere 2012 (IRI-2012) Model was used as a background for ionospheric interpolation to calculate regional variant. The mapping accuracy is estimated using ionosonde data derived from seven stations in mideastern China: Xinxiang (35.2°S, 113.9°E), Wuhan (30.6°S, 114.6°E), Qingdao (36.1°S, 12.4°E), Suzhou (30.3°S, 120.6°E), Xian (34.3°S, 108.9°E), Chongqing (29.6°S, 106.5°E), and Guangzhou (23.1°S, 113.3°E). The data were recorded approximately every 15 min during two recording intervals between 04:00 UTC LT on 31 October 2012, and 03:30 UTC on 1 November 2012. The estimates of foF2 obtained from the reconstruction method and the foF2 values predicted using IRI are compared with the measurements from the vertical ionosondes at the above seven stations. The root-mean-square error and percent deviation are calculated to evaluate the performance of the inversion model. The results indicate that the new method for real-time foF2 mapping based on shortwave signals is a promising candidate technique for obtaining ionospheric parameters and studying the ionosphere.

  14. Long-term trends of foF2 independent of geomagnetic activity

    Directory of Open Access Journals (Sweden)

    A. D. Danilov

    Full Text Available A detailed analysis of the foF2 data at a series of ionospheric stations is performed to reveal long-term trends independent of the long-term changes in geomagnetic activity during the recent decades (nongeomagnetic trends. The method developed by the author and published earlier is used. It is found that the results for 21 out of 23 stations considered agree well and give a relative nongeomagnetic trend of -0.0012 per year (or an absolute nongeomagnetic trend of about -0.012 MHz per year for the period between 1958 and the mid-nineties. The trends derived show no dependence on geomagnetic latitude or local time, a fact confirming their independence of geomagnetic activity. The consideration of the earlier period (1948–1985 for a few stations for which the corresponding data are available provides significantly lower foF2 trends, the difference between the later and earlier periods being a factor of 1.6. This is a strong argument in favor of an anthropogenic nature of the trends derived.Key words. Ionosphere (ionosphere-atmosphere interactions; ionospheric disturbances; mid-latitude ionosphere

  15. Enhancement of wind stress evaluation method under storm conditions

    Science.gov (United States)

    Chen, Yingjian; Yu, Xiping

    2016-12-01

    Wind stress is an important driving force for many meteorological and oceanographical processes. However, most of the existing methods for evaluation of the wind stress, including various bulk formulas in terms of the wind speed at a given height and formulas relating the roughness height of the sea surface with wind conditions, predict an ever-increasing tendency of the wind stress coefficient as the wind speed increases, which is inconsistent with the field observations under storm conditions. The wave boundary layer model, which is based on the momentum and energy conservation, has the advantage to take into account the physical details of the air-sea interaction process, but is still invalid under storm conditions without a modification. By including the energy dissipation due to the presence of sea spray, which is speculated to be an important aspect of the air-sea interaction under storm conditions, the wave boundary layer model is improved in this study. The improved model is employed to estimate the wind stress caused by an idealized tropical cyclone motion. The computational results show that the wind stress coefficient reaches its maximal value at a wind speed of about 40 m/s and decreases as the wind speed further increases. This is in fairly good agreement with the field data.

  16. Long-term trends of foE and geomagnetic activity variations

    Directory of Open Access Journals (Sweden)

    A. V. Mikhailov

    2003-03-01

    Full Text Available A relationship between foE trends and geomagnetic activity long-term variations has been revealed for the first time. By analogy with earlier obtained results on the foF2 trends it is possible to speak about the geomagnetic control of the foE long-term trends as well. Periods of increasing geomagnetic activity correspond to negative foE trends, while these trends are positive for the decreasing phase of geomagnetic activity. This "natural" relationship breaks down around 1970 (on some stations later when pronounced positive foE trends have appeared on most of the stations considered. The dependence of foE trends on geomagnetic activity can be related with nitric oxide variations at the E-layer heights. The positive foE trends that appeared after the "break down" effect may also be explained by the [NO] decrease which is not related to geomagnetic activity variations. But negative trends or irregular foE variations on some stations for the same time period require some different mechanism. Chemical pollution of the lower thermosphere due to the anthropogenic activity may be responsible for such abnormal foE behavior after the end of the 1960s.Key words. Ionosphere (ionosphere-atmosphere interactions; ionospheric disturbances

  17. Parameter Estimation for GRACE-FO Geometric Ranging Errors

    Science.gov (United States)

    Wegener, H.; Mueller, V.; Darbeheshti, N.; Naeimi, M.; Heinzel, G.

    2017-12-01

    Onboard GRACE-FO, the novel Laser Ranging Instrument (LRI) serves as a technology demonstrator, but it is a fully functional instrument to provide an additional high-precision measurement of the primary mission observable: the biased range between the two spacecraft. Its (expectedly) two largest error sources are laser frequency noise and tilt-to-length (TTL) coupling. While not much can be done about laser frequency noise, the mechanics of the TTL error are widely understood. They depend, however, on unknown parameters. In order to improve the quality of the ranging data, it is hence essential to accurately estimate these parameters and remove the resulting TTL error from the data.Means to do so will be discussed. In particular, the possibility of using calibration maneuvers, the utility of the attitude information provided by the LRI via Differential Wavefront Sensing (DWS), and the benefit from combining ranging data from LRI with ranging data from the established microwave ranging, will be mentioned.

  18. INFLUENCE OF CUTTING ZONE COOLING METHOD ON CHIP FORMING CONDITIONS

    Directory of Open Access Journals (Sweden)

    E. E. Feldshtein

    2014-01-01

    Full Text Available The paper considers an influence of a cutting zone cooling method on the chip shape and thickening ratio while turning R35 steel with the hardness of НВ 1250 МРа. Cutting with various types of cooling - dry, compressed air and emulsion fog has been investigated in the paper. OPORTET RG-2 emulsol with emulsion concentration of 4% has been used as an active substation. Cutting tool is a turning cutter with a changeable square plate SNUN120408 made of Р25 hard alloy with multilayer wear-resistant coating, upper titanium nitride layer. Front plate surface is flat. Range of cutting speeds - 80-450 m/min, motions - 0,1-0,5 mm/rev, emulsion flow - 1,5-3,5 g/min and compressed air - 4,5-7,0 m3/h, cutting depth - 1,0 mm. In order to reduce a number of single investigations it is possible to use plans based on ЛПх-sequences.It has been shown that the method for cutting zone cooling exerts significant influence on conditions for chip formation. Regression equation describing influence of machining conditions on Ка-chip thickening ratio has been obtained in the paper. The range of cutting modes is extended while using emulsion fog for cooling. In the process of these modes chip is formed in the shape of short spiral fragments or elements. Favourable form of chips is ensured while using the following rate of emulsion - not more than 2 g/min. The investigations have made it possible to determine conditions required for cooling emulsion fog. In this case it has been observed minimum values in chip thickening ratio and chip shape that ensures its easy removal from cutting zone. While making dry turning values of Ка is higher not less than 15 % in comparison with other methods for cutting zone cooling.

  19. NNWSI waste form test method for unsaturated disposal conditions

    International Nuclear Information System (INIS)

    Bates, J.K.; Gerding, T.J.

    1985-03-01

    A test method has been developed to measure the release of radionuclides from the waste package under simulated NNWSI repository conditions, and to provide information concerning materials interactions that may occur in the repository. Data are presented from Unsaturated testing of simulated Savannah River Laboratory 165 glass completed through 26 weeks. The relationship between these results and those from parametric and analog testing are described. The data indicate that the waste form test is capable of producing consistent, reproducible results that will be useful in evaluating the role of the waste package in the long-term performance of the repository. 6 refs., 7 figs., 5 tabs

  20. Conditional Hyperbolic Quadrature Method of Moments for Kinetic Equations

    OpenAIRE

    Fox, Rodney,; Laurent, Frédérique; Vié, Aymeric

    2017-01-01

    The conditional quadrature method of moments (CQMOM) was introduced by Yuan and Fox [J. Comput. Phys. 230 (22), 8216–8246 (2011)] to reconstruct a velocity distribution function (VDF) from a finite set of its integer moments. The reconstructed VDF takes the form of a sum of weighted Dirac delta functions in velocity phase space, and provides a closure for the spatial flux term in the corresponding kinetic equation. The CQMOM closure for the flux leads to a weakly hyperbolic system of moment e...

  1. On a selection method of imaging condition in scintigraphy

    International Nuclear Information System (INIS)

    Ikeda, Hozumi; Kishimoto, Kenji; Shimonishi, Yoshihiro; Ohmura, Masahiro; Kosakai, Kazuhisa; Ochi, Hironobu

    1992-01-01

    Selection of imaging condition in scintigraphy was evaluated using analytic hierarchy process. First, a method of the selection was led by determining at the points of image quantity and imaging time. Influence of image quality was thought to depend on changes of system resolution, count density, image size, and image density. Also influence of imaging time was thought to depend on changes of system sensitivity and data acquisition time. Phantom study was done for paired comparison of these selection factors, and relations of sample data and the factors, that is Rollo phantom images were taken by changing count density, image size, and image density. Image quality was shown by calculating the score of visual evaluation that done by comparing of a pair of images in clearer cold lesion on the scintigrams. Imaging time was shown by relative values for changes of count density. However, system resolution and system sensitivity were constant in this study. Next, using these values analytic hierarchy process was adapted for this selection of imaging conditions. We conclude that this selection of imaging conditions can be analyzed quantitatively using analytic hierarchy process and this analysis develops theoretical consideration of imaging technique. (author)

  2. SuperSTAR-FO, the accelerometers for the GRACE-FO mission: improvement and evolution since GRACE

    Science.gov (United States)

    Christophe, B.; Foulon, B.; Boulanger, D.; Lebat, V.; Liorzou, F.

    2012-04-01

    SuperSTAR-FO, the accelerometer proposed for the GRACE Follow-On mission is very similar to the SuperSTAR models operating since ten years on board the twin GRACE satellites. However, lessons learned from the GRACE mission and also from the six GRADIO models composing the three axis gravity gradiometer of the GOCE ESA mission, lead to minor modifications in the packaging and some electronics circuits, in particular for improving the thermal behaviour of the instrument. The presentation will describe the evolution of the instrument, its performance, in particular in terms of thermal stability, and the ground testing philosophy in order to match the bias and scale factor of the instrument before launch.

  3. Space Weathering of Silicates Simulated by Successive Laser Irradiation: In Situ Reflectance Measurements of Fo90, Fo99+, and Sio2

    Science.gov (United States)

    Loeffler, M. J.; Dukes, C. A.; Christoffersen, R.; Baragiola, R. A.

    2016-01-01

    Pulsed-laser irradiation causes the visible-near-infrared spectral slope of olivine (Fo90 and Fo99+) and SiO2 to increase (redden), while the olivine samples darken and the SiO2 samples brighten slightly. XPS analysis shows that irradiation of Fo90 produces metallic Fe. Analytical SEM and TEM measurements confirm that reddening in the Fo90 olivine samples correlates with the production of nanophase metallic Fe (npFe0) grains, 2050 nm in size. The reddening observed in the SiO2 sample is consistent with the formation of SiO or other SiOx species that absorb in the visible. The weak spectral brightening induced by laser irradiation of SiO2 is consistent with a change in surface topography of the sample. The darkening observed in the olivine samples is likely caused by the formation of larger npFe0 particles, such as the 100400 nm diameter npFe0 identified during our TEM analysis of Fo90 samples. The Fo90 reflectance spectra are qualitatively similar to those in previous experiments suggesting that in all cases formation of npFe0 is causing the spectral alteration. Finally, we find that the accumulation of successive laserpulses cause continued sample darkening in the Vis-NIR, which suggests that repeated surface impacts are an efficient way to darken airless body surfaces.

  4. Emerging forward osmosis (FO) technologies and challenges ahead for clean water and clean energy applications

    KAUST Repository

    Chung, Tai-Shung

    2012-08-01

    The purpose of this short review is to share our understanding and perspectives with the chemical, environmental, water and osmotic power communities on FO processes in order to conduct meaningful R & D and develop effective and sustainable FO technologies for clean water and clean energy. © 2012 Elsevier Ltd. All rights reserved.

  5. GRACE-FO: seeking an optimal mission scenario

    Science.gov (United States)

    Biancale, R.; Lemoine, J.-M.; Bruinsma, S.; Perosanz, F.; da Costa, E. D.

    2009-04-01

    The GRACE mission has brought enormous improvement in the knowledge of the Earth's gravity field and particularly in its temporal evolution, which has led to a large amount of applied research in geosciences. It has demonstrated the capability of measuring the effect of gravitation in space to monitor surface water changes globally (through a satellite-to-satellite tracking technique of very high accuracy) and the question of a follow-on mission has been raised. Of course, spatial and temporal resolution remain coarse, at the level of some 500 km / 10 days to a month, respectively. However, this limitation is not only due to the mission's characteristics, but also to some limitation of aliased effects of higher frequency, such as from ocean tides and from atmosphere perturbations, which are today not modelled precisely enough. Nevertheless, it is essential to persevere in continuing the monitoring from space of global water changes. That is why CNES/GRGS performed a series of simulations for a proposed GRACE-FO mission under different scenario assumptions, considering a range or range-rate link between two or more satellites. Characteristics and results of these simulations will be presented.

  6. The CURL-CoFoR Collaborative Collection Management Project

    Directory of Open Access Journals (Sweden)

    Gregory Walker

    2005-09-01

    Full Text Available CoFoR originated from an initiative by CURL, the Consortium of Research Libraries in the British Isles. CURL’s Task Force on Resource Management proposed a project, which would develop and test several interrelated aspects of collaborative collection management (CCM, to help in determining the most effective kinds of collaboration between major research collections. The Task Force was concerned that local pressures on libraries were tending to make them take collection management decisions in isolation, and they were looking for a framework within which better informed decisions on libraries’ collections could be taken with greater confidence and a clearer awareness of national provision. CURL was seeking to establish which CCM approaches could be expected to: · offer the most attractive benefits for costs incurred; · be applicable to a wide range of subjects / areas; · and be viable in the longer term. In lat 2002 CURL accepted a proposal from an existing project team to undertake this work.

  7. Facile route of biopolymer mediated ferrocene (FO) nanoparticles in aqueous dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Kaus, Noor Haida Mohd., E-mail: noorhaida@usm.my [School of Chemical Sciences, Universiti Sains Malaysia, 11800, Penang, Malaysia and Centre for Organized Matter Chemistry, School of Chemistry, Cantock' s Close, BS8 1TS, Bristol (United Kingdom); Collins, A. M.; Mann, S. [Centre for Organized Matter Chemistry, School of Chemistry, Cantock' s Close, BS8 1TS, Bristol (United Kingdom)

    2014-10-24

    In this paper, we present a facile method for production stable aqueous dispersion of ferrocene (FO) nanoparticles. Ferrocene compounds were employed to achieve stable nanodispersions, stabilized with three different biopolymers namely, alginate, CM-dextran and chitosan. The nanoparticles produce are spherical, less than 10 nm in mean diameter and highly stable without any sedimentation. Fourier infrared transform (FTIR) and X-ray diffraction (XRD) studies confirmed the purity of ferrocene nanoparticles there is no modifications occur during the preparation route. FTIR spectra results were consistent with the presence of absorption band of cyclopentadienyl ring (C{sub 5}H{sub 5}{sup −} ion) which assigned to ν(C-C) vibrations (1409 cm-1), δ(C-H) stretching at 1001 cm{sup −1} and π(C-H) vibrations at 812 cm{sup −1}. Furthermore, all functional group for biopolymers such as CO from carboxyl group of CM-dextran and sodium alginate appears at 1712 cm{sup −1} and 1709 cm{sup −1} respectively, indicating there are steric repulsion interactions for particles stabilization. Powder X-ray diffraction patterns of sedimented samples of the biopolymers-stabilized ferrocene (FO) showed all reflections which were indexed respectively to the (−110), (001), (−201), (−111), (200), (−211), (210), (120) and (111) according to the monoclinic phase ferrocene. This confirmed that the products obtained were of high purity of Fe and EDAX analysis also suggests that the presence of the Fe element in the colloidal dispersion.

  8. Iterative methods for symmetric ill-conditioned Toeplitz matrices

    Energy Technology Data Exchange (ETDEWEB)

    Huckle, T. [Institut fuer Informatik, Muenchen (Germany)

    1996-12-31

    We consider ill-conditioned symmetric positive definite, Toeplitz systems T{sub n}x = b. If we want to solve such a system iteratively with the conjugate gradient method, we can use band-Toeplitz-preconditioners or Sine-Transform-peconditioners M = S{sub n}{Lambda}S{sub n}, S{sub n} the Sine-Transform-matrix and {Lambda} a diagonal matrix. A Toeplitz matrix T{sub n} = (t{sub i-j)}{sub i}{sup n},{sub j=1} is often related to an underlying function f defined by the coefficients t{sub j}, j = -{infinity},..,-1,0, 1,.., {infinity}. There are four cases, for which we want to determine a preconditioner M: - T{sub n} is related to an underlying function which is given explicitly; - T{sub n} is related to an underlying function that is given by its Fourier coefficients; - T{sub n} is related to an underlying function that is unknown; - T{sub n} is not related to an underlying function. Especially for the first three cases we show how positive definite and effective preconditioners based on the Sine-Transform can be defined for general nonnegative underlying function f. To define M, we evaluate or estimate the values of f at certain positions, and build a Sine-transform matrix with these values as eigenvalues. Then, the spectrum of the preconditioned system is bounded from above and away from zero.

  9. Control system and method for a universal power conditioning system

    Science.gov (United States)

    Lai, Jih-Sheng; Park, Sung Yeul; Chen, Chien-Liang

    2014-09-02

    A new current loop control system method is proposed for a single-phase grid-tie power conditioning system that can be used under a standalone or a grid-tie mode. This type of inverter utilizes an inductor-capacitor-inductor (LCL) filter as the interface in between inverter and the utility grid. The first set of inductor-capacitor (LC) can be used in the standalone mode, and the complete LCL can be used for the grid-tie mode. A new admittance compensation technique is proposed for the controller design to avoid low stability margin while maintaining sufficient gain at the fundamental frequency. The proposed current loop controller system and admittance compensation technique have been simulated and tested. Simulation results indicate that without the admittance path compensation, the current loop controller output duty cycle is largely offset by an undesired admittance path. At the initial simulation cycle, the power flow may be erratically fed back to the inverter causing catastrophic failure. With admittance path compensation, the output power shows a steady-state offset that matches the design value. Experimental results show that the inverter is capable of both a standalone and a grid-tie connection mode using the LCL filter configuration.

  10. Description of a method for assessing veld condition in the Karoo ...

    African Journals Online (AJOL)

    Keywords: Canopy-spread cover; Current grazing capacity; Dry matter; Ecological index method; Forage; Grazing-index method; Karoo; Line-point survey method; Strikes; Veld condition; Veld condition index; botany; method; south africa; razing-index method; razing capacity; ine-point survey method; eld condition index

  11. Methods for evaluating stream, riparian, and biotic conditions

    Science.gov (United States)

    William S. Platts; Walter F. Megahan; G. Wayne Minshall

    1983-01-01

    This report develops a standard way of measuring stream, riparian, and biotic conditions and evaluates the validity of the measurements recommended. Accuracy and precision of most measurements are defined. This report will be of value to those persons documenting, monitoring, or predicting stream conditions and their biotic resources, especially those related to...

  12. Effect of surface conditioning methods on the microtensile bond strength of resin composite to composite after aging conditions

    NARCIS (Netherlands)

    Ozcan, Mutlu; Barbosa, Silvia Helena; Melo, Renata Marques; Galhano, Graziela Avila Prado; Bottino, Marco Antonio

    2007-01-01

    Objectives. This study evaluated the effect of two different surface conditioning methods on the repair bond strength of a bis-GMA-adduct/bis-EMA/TEGDMA based resin composite after three aging conditions. Methods. Thirty-six composite resin blocks (Esthet X, Dentsply) were prepared (5 mm x 6 mm x 6

  13. DO TIE LABORATORY BASED METHODS REALLY REFLECT FIELD CONDITIONS

    Science.gov (United States)

    Sediment Toxicity Identification and Evaluation (TIE) methods have been developed for both interstitial waters and whole sediments. These relatively simple laboratory methods are designed to identify specific toxicants or classes of toxicants in sediments; however, the question ...

  14. Method for accelerated aging under combined environmental stress conditions

    International Nuclear Information System (INIS)

    Gillen, K.T.

    1979-01-01

    An accelerated aging method which can be used to simulate aging in combined stress environment situations is described. It is shown how the assumptions of the method can be tested experimentally. Aging data for a chloroprene cable jacketing material in single and combined radiation and temperature environments are analyzed and it is shown that these data offer evidence for the validity of the method

  15. On angle conditions in the finite element method

    Czech Academy of Sciences Publication Activity Database

    Brandts, J.; Hannukainen, A.; Korotov, S.; Křížek, Michal

    2011-01-01

    Roč. 56, - (2011), s. 81-95 ISSN 1575-9822 R&D Projects: GA AV ČR(CZ) IAA100190803 Institutional research plan: CEZ:AV0Z10190503 Keywords : simplicial finite elements * minimum and maximum angle condition * ball conditions Subject RIV: BA - General Mathematics http://www.sema.org.es/ojs/index.php?journal=journal&page=article&op=viewArticle&path%5B%5D=612

  16. A wide-FoV athermalized infrared imaging system with a two-element lens

    Science.gov (United States)

    Feng, Bin; Shi, Zelin; Zhao, Yaohong; Liu, Haizheng; Liu, Li

    2017-12-01

    For infrared imaging systems to achieve wide field of view (FoV), wide operating temperature and low weight, this work designs a wide-FoV athermalized infrared imaging system (AIIS) with a two-element lens. Its principle, design, manufacture, measurement and performance validation are successively discussed. The two-element lens contains four surfaces, where three aspheric surfaces are introduced to reduce optical off-axis aberrations and a cubic surface is introduced to achieve athermalization. The key coding mask containing an aspheric surface and a cubic surface is manufactured by nano-metric machining of ion implanted material (NiIM). Experimental results validate that our wide-FoV wavefront coding AIIS has a full FoV of 26.10° and an operating temperature over -20 °C to +70 °C.

  17. Systems and method for lagrangian monitoring of flooding conditions

    KAUST Repository

    Claudel, Christian G.

    2015-12-17

    A traffic monitoring system and method for mapping traffic speed and density while preserving privacy. The system can include fixed stations that make up a network and mobile probes that are associated with vehicles. The system and method do not gather, store, or transmit any unique or identifying information, and thereby preserves the privacy of members of traffic. The system and method provide real-time traffic density and speed mapping. The system and method can further be integrated with a complementary flood monitoring system and method.

  18. Cyclophilin D Promotes Brain Mitochondrial F1FO ATP Synthase Dysfunction in Aging Mice.

    Science.gov (United States)

    Gauba, Esha; Guo, Lan; Du, Heng

    2017-01-01

    Brain aging is the known strongest risk factor for Alzheimer's disease (AD). In recent years, mitochondrial deficits have been proposed to be a common mechanism linking brain aging to AD. Therefore, to elucidate the causative mechanisms of mitochondrial dysfunction in aging brains is of paramount importance for our understanding of the pathogenesis of AD, in particular its sporadic form. Cyclophilin D (CypD) is a specific mitochondrial protein. Recent studies have shown that F1FO ATP synthase oligomycin sensitivity conferring protein (OSCP) is a binding partner of CypD. The interaction of CypD with OSCP modulates F1FO ATP synthase function and mediates mitochondrial permeability transition pore (mPTP) opening. Here, we have found that increased CypD expression, enhanced CypD/OSCP interaction, and selective loss of OSCP are prominent brain mitochondrial changes in aging mice. Along with these changes, brain mitochondria from the aging mice demonstrated decreased F1FO ATP synthase activity and defective F1FO complex coupling. In contrast, CypD deficient mice exhibited substantially mitigated brain mitochondrial F1FO ATP synthase dysfunction with relatively preserved mitochondrial function during aging. Interestingly, the aging-related OSCP loss was also dramatically attenuated by CypD depletion. Therefore, the simplest interpretation of this study is that CypD promotes F1FO ATP synthase dysfunction and the resultant mitochondrial deficits in aging brains. In addition, in view of CypD and F1FO ATP synthase alterations seen in AD brains, the results further suggest that CypD-mediated F1FO ATP synthase deregulation is a shared mechanism linking mitochondrial deficits in brain aging and AD.

  19. Sustainable water recovery from oily wastewater via forward osmosis-membrane distillation (FO-MD).

    Science.gov (United States)

    Zhang, Sui; Wang, Peng; Fu, Xiuzhu; Chung, Tai-Shung

    2014-04-01

    This study proposed and investigated a hybrid forward osmosis - membrane distillation (FO-MD) system for sustainable water recovery from oily wastewater by employing lab-fabricated FO and MD hollow fiber membranes. Stable oil-in-water emulsions of different concentrations with small droplet sizes (membranes. Moreover, slight increment of fouling was observed in the first few hours and the water flux was then stabilized over 24 h. The characterizations of water flux and solute rejection in separate FO and MD processes revealed that a high water flux, good NaCl rejection, impressively high retention of oil droplets and partial permeation of acetic acid could be achieved. Finally, an integrated FO-MD system was developed to treat the oily wastewater containing petroleum, surfactant, NaCl and acetic acid at 60 °C in the batch mode. The water flux in FO undergoes three-stage decline due to fouling and reduction in osmotic driving force, but is quite stable in MD regardless of salt concentration. Oily wastewater with relatively high salinity could be effectively recovered by the FO-MD hybrid system while maintaining large water flux, at least 90% feed water recovery could be readily attained with only trace amounts of oil and salts, and the draw solution was re-generated for the next rounds of FO-MD run. Interestingly, significant amount of acetic acid was also retained in the permeate for further reuse as a chemical additive during the production of crude oil. The work has demonstrated that not only water but also organic additives in the wastewater could be effectively recovered by FO-MD systems for reuse or other utilizations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. F.O. Schechtel’s house on bolshaya sadovaya street as an object of cultural heritage

    Directory of Open Access Journals (Sweden)

    Gatsunaev Konstantin Nikolaevich

    2016-10-01

    Full Text Available F.O. Schechtel’s private house on Bolshaya Sadovaya Street in Moscow built in 1910 became a peculiar result of creative activity of the most famous architect of an era of “Silver age” of the Russian culture. The highest professionalism of the architect was expressed not only in composite decisions and the system of decor of the building, but also in organizational and technical aspects of his construction. The former F.O. Schechtel’s mansion for several decades has been one of the centers of Moscow’s cultural life. The memorial value of the house consists not only of its architectural advantages. The building keeps the memory of F.O. Schechtel - a first-class architect, stenographer, illustrator and graphic artist, a master of applied art, a public figure and a teacher. He personified the best qualities of Russian intellectuals: high ethical standards and active living position. The activity of the architect Schechtel was exclusively fruitful both in quantitative, and in qualitative sense. There are about fifty buildings in Moscow which were constructed according to his projects. Each of them comprised opening and generating of a new direction or introduction of new methods of construction. Schechtel gave other architects an opportunity to further develop these methods. The structures built upon Schechtel’s projects in many respects have defined unique lines of Moscow city landscape of the end of 19th - the beginning of the 20th centuries. Numerous relatives of Schechtel lived in the mansion and in its wings in addition to the head of the family. The contribution of each of them to the development of the Russian culture is significant.

  1. System and method of vehicle operating condition management

    Science.gov (United States)

    Sujan, Vivek A.; Vajapeyazula, Phani; Follen, Kenneth; Wu, An; Moffett, Barty L.

    2015-10-20

    A vehicle operating condition profile can be determined over a given route while also considering imposed constraints such as deviation from time targets, deviation from maximum governed speed limits, etc. Given current vehicle speed, engine state and transmission state, the present disclosure optimally manages the engine map and transmission to provide a recommended vehicle operating condition that optimizes fuel consumption in transitioning from one vehicle state to a target state. Exemplary embodiments provide for offline and online optimizations relative to fuel consumption. The benefit is increased freight efficiency in transporting cargo from source to destination by minimizing fuel consumption and maintaining drivability.

  2. Three State-of-the-Art Methods for Condition Monitoring

    NARCIS (Netherlands)

    Grimmelius, H.T.; Meiler, P.P.; Maas, H.L.M.M.; Bonnier, B.; Grevink, J.S.; Kuilenburg, R.F. van

    1999-01-01

    This paper describes and compares three different state-of-the-art condition monitoring techniques: first principles, feature extraction, and neural networks. The focus of the paper is on the application of the techniques, not on the underlying theory. Each technique is described briefly and is

  3. Methods to Enrich Exosomes from Conditioned Media and Biological Fluids.

    Science.gov (United States)

    Sharma, Shayna; Scholz-Romero, Katherin; Rice, Gregory E; Salomon, Carlos

    2018-01-01

    Exosomes are nano-vesicles which can transport a range of molecules including but not limited to proteins and miRNA. This ability of exosomes renders them useful in cellular communication often resulting in biological changes. They have several functions in facilitating normal biological processes such as immune responses and an involvement in pregnancy. However, they have also been linked to pathological conditions including cancer and pregnancy complications such as preeclampsia. An understanding for the role of exosomes in preeclampsia is based on the ability to purify and characterize exosomes. There have been several techniques proposed for the enrichment of exosomes such as ultracentrifugation, density gradient separation, and ultrafiltration although there is no widely accepted optimized technique. Here we describe a workflow for isolating exosomes from cell-conditioned media and biological fluids using a combination of centrifugation, buoyant density, and ultrafiltration approaches.

  4. Methods of forecasting crack growth rate under creep conditions

    International Nuclear Information System (INIS)

    Ol'kin, S.I.

    1979-01-01

    Using construction aluminium alloy application possibility of linear mechanics of the destruction for quantitative description of crack development process under creepage conditions is investigated. It is shown, that the grade dependence between the stress intensity coefficient and the crack growth rate takes place only at certain combination of the sample geometry and creepage parameters, and consequently, its applicability in every given case must necessarily be tested experimentally

  5. Method of the quasilinearization for nonlinear impulsive differential equations with linear boundary conditions

    Directory of Open Access Journals (Sweden)

    Paul Eloe

    2002-01-01

    Full Text Available The method of quasilinearization for nonlinear impulsive differential equations with linear boundary conditions is studied. The boundary conditions include periodic boundary conditions. It is proved the convergence is quadratic.

  6. Bioimpedance spectroscopy method to determine hypervolemia in maintenance hemodialysis patients

    OpenAIRE

    Merhametsiz, O; Oguz, EG; Yayar, O; Bektan, B; Canbakan, B; Ayli, D

    2015-01-01

    Background: Hypervolemia is a major risk factor for hypertension leading to cardiovascular diseases and also a frequent problem in maintenance hemodialysis (MHD) patients. Fluid overload (FO) can be determined by bioimpedance spectroscopy (BIS) which is a new, practical, and non-invasive method. We tried to determine FO by BIS in MHD patients and find out the relationship between FO and clinical features.

  7. Liquid over-feeding air conditioning system and method

    Science.gov (United States)

    Mei, V.C.; Chen, F.C.

    1993-09-21

    A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant. 1 figure.

  8. Improved method for measuring fluid loss at simulated fracture conditions

    Energy Technology Data Exchange (ETDEWEB)

    McDaniel, R.R.; Deysarkar, A.K.; Callanan, M.J.; Kohlhaas, C.A.

    1981-01-01

    A test apparatus is designed to carry out dynamic as well as static fluid loss tests of fracturing fluids. This test apparatus simulates the pressure difference, temperature, rate of shear, duration of shear, and fluid flow pattern expected under fracture conditions. For a typical crosslinked fracturing fluid, experimental results indicate that fluid loss values can be a function of temperature, pressure differential, rate of shear, and degree of non-Newtonian behavior of the fracturing fluid. A mathematical development is presented to calculate the fracturing fluid coefficient obtained from laboratory studies assuming this to be a combination of fracturing fluid coefficient and filter cake coefficient.

  9. Reliable iterative methods for solving ill-conditioned algebraic systems

    NARCIS (Netherlands)

    Padiy, Alexander

    2000-01-01

    The finite element method is one of the most popular techniques for numerical solution of partial differential equations. The rapid performance increase of modern computer systems makes it possible to tackle increasingly more difficult finite-element models arising in engineering practice. However,

  10. Fatigue testing of materials under extremal conditions by acoustic method

    NARCIS (Netherlands)

    Baranov, VM; Bibilashvili, YK; Karasevich, VA; Sarychev, GA

    2004-01-01

    Increasing fuel cycle time requires fatigue testing of the fuel clad materials for nuclear reactors. The standard high-temperature fatigue tests are complicated and tedious. Solving this task is facilitated by the proposed acoustic method, which ensures observation of the material damage dynamics,

  11. Impacts of an Innovative Residential Construction Method on Internal Conditions

    Directory of Open Access Journals (Sweden)

    Roger Birchmore

    2015-02-01

    Full Text Available New Zealand houses are known for producing sub-optimal internal thermal conditions and unacceptably high internal moisture levels. These contribute to poor levels of health, mould and can coincide with the decay of structural timber frames. A proposed solution is to provide an alternative structure utilising plywood, a vapour check on the internal face of the timber frame and an additional air gap, followed by the internal lining. The internal vapour check is designed to prevent moisture vapour diffusion from inside into the frame and to permit moisture diffusion from outside through the structure to the internal environment. Two full scale houses had temperatures, dew points and humidity levels monitored in passive, unoccupied conditions. The test case house incorporated the innovative construction solution. The control house was of identical design and location, using standard construction practice. The calculated internal moisture content profile appeared to be unrelated to the external moisture content as expected, instead following the profile of the changing internal temperature. Whilst the innovative construction appeared to prevent moisture diffusion into the structure in winter and permit it inside in summer, this resulted in a generally higher internal relative humidity than the control house.

  12. Torque-coupled thermodynamic model for FoF1 -ATPase

    Science.gov (United States)

    Ai, Guangkuo; Liu, Pengfei; Ge, Hao

    2017-05-01

    FoF1 -ATPase is a motor protein complex that utilizes transmembrane ion flow to drive the synthesis of adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and phosphate (Pi). While many theoretical models have been proposed to account for its rotary activity, most of them focus on the Fo or F1 portions separately rather than the complex as a whole. Here, we propose a simple but new torque-coupled thermodynamic model of FoF1 -ATPase. Solving this model at steady state, we find that the monotonic variation of each portion's efficiency becomes much more robust over a wide range of parameters when the Fo and F1 portions are coupled together, as compared to cases when they are considered separately. Furthermore, the coupled model predicts the dependence of each portion's kinetic behavior on the parameters of the other. Specifically, the power and efficiency of the F1 portion are quite sensitive to the proton gradient across the membrane, while those of the Fo portion as well as the related Michaelis constants for proton concentrations respond insensitively to concentration changes in the reactants of ATP synthesis. The physiological proton gradient across the membrane in the Fo portion is also shown to be optimal for the Michaelis constants of ADP and phosphate in the F1 portion during ATP synthesis. Together, our coupled model is able to predict key dynamic and thermodynamic features of the FoF1 -ATPase in vivo semiquantitatively, and suggests that such coupling approach could be further applied to other biophysical systems.

  13. Expanding the applicability of the Secant method under weaker conditions

    OpenAIRE

    Argyros, Ioannis K; Magreñán, Á. Alberto (UNIR)

    2015-01-01

    We present a new semilocal convergence analysis for Secant method in order to approximate a locally unique solution of a nonlinear equation in a Banach space setting. Our analysis includes the computation of the bounds on the limit points of the majorizing sequences involved. Under the same computational cost on the parameters involved our convergence criteria are weaker and the error bounds more precise than in earlier studies such as (Amat and Busquier, 2003; Amat et al., in press; Argyros ...

  14. New methods for the condition monitoring of level crossings

    Science.gov (United States)

    García Márquez, Fausto Pedro; Pedregal, Diego J.; Roberts, Clive

    2015-04-01

    Level crossings represent a high risk for railway systems. This paper demonstrates the potential to improve maintenance management through the use of intelligent condition monitoring coupled with reliability centred maintenance (RCM). RCM combines advanced electronics, control, computing and communication technologies to address the multiple objectives of cost effectiveness, improved quality, reliability and services. RCM collects digital and analogue signals utilising distributed transducers connected to either point-to-point or digital bus communication links. Assets in many industries use data logging capable of providing post-failure diagnostic support, but to date little use has been made of combined qualitative and quantitative fault detection techniques. The research takes the hydraulic railway level crossing barrier (LCB) system as a case study and develops a generic strategy for failure analysis, data acquisition and incipient fault detection. For each barrier the hydraulic characteristics, the motor's current and voltage, hydraulic pressure and the barrier's position are acquired. In order to acquire the data at a central point efficiently, without errors, a distributed single-cable Fieldbus is utilised. This allows the connection of all sensors through the project's proprietary communication nodes to a high-speed bus. The system developed in this paper for the condition monitoring described above detects faults by means of comparing what can be considered a 'normal' or 'expected' shape of a signal with respect to the actual shape observed as new data become available. ARIMA (autoregressive integrated moving average) models were employed for detecting faults. The statistical tests known as Jarque-Bera and Ljung-Box have been considered for testing the model.

  15. Mechanistic Basis for Differential Inhibition of the F1Fo-ATPase by Aurovertin

    Science.gov (United States)

    Johnson, Kathryn M.; Swenson, Lara; Opipari, Anthony W.; Reuter, Rolf; Zarrabi, Nawid; Fierke, Carol A.; Börsch, Michael; Glick, Gary D.

    2009-01-01

    The mitochondrial F1Fo-ATPase performs the terminal step of oxidative phosphorylation. Small molecules that modulate this enzyme have been invaluable in helping decipher F1Fo-ATPase structure, function, and mechanism. Aurovertin is an antibiotic that binds to the β subunits in the F1 domain and inhibits F1Fo-ATPase-catalyzed ATP synthesis in preference to ATP hydrolysis. Despite extensive study and the existence of crystallographic data, the molecular basis of the differential inhibition and kinetic mechanism of inhibition of ATP synthesis by aurovertin has not been resolved. To address these questions, we conducted a series of experiments in both bovine heart mitochondria and E. coli membrane F1Fo-ATPase. Aurovertin is a mixed, noncompetitive inhibitor of both ATP hydrolysis and synthesis with lower Ki values for synthesis. At low substrate concentrations, inhibition is cooperative suggesting a stoichiometry of two aurovertin per F1F0-ATPase. Furthermore, aurovertin does not completely inhibit the ATP hydrolytic activity at saturating concentrations. Single-molecule experiments provide evidence that the residual rate of ATP hydrolysis seen in the presence of saturating concentrations of aurovertin results from a decrease in the binding change mechanism by hindering catalytic site interactions. The results from these studies should further the understanding of how the F1Fo-ATPase catalyzes ATP synthesis and hydrolysis. PMID:19462418

  16. Controlling the morphology and performance of FO membrane via adjusting the atmosphere humidity during casting procedure

    Science.gov (United States)

    Zuo, Hao-Ran; Cao, Gui-Ping; Wang, Meng; Zhang, Huan-Huan; Song, Chen-Chen; Fang, Xu; Wang, Tao

    2018-03-01

    Forward osmosis (FO) has received great interest for its considerable potential in a wide range of fields. In this work, the morphology and performance of FO membrane were regulated by adjusting the atmosphere humidity (HC) of casting procedure. The polysulfone support layer was casted under various atmosphere humidity levels ranging from 40% to 80%. By multi-techniques such as SEM, AFM, and XPS, it was proved that the atmosphere humidity had modified the surface morphology and thickness of the skin layer in support layer, which contributed up to 90% of the structure parameter, resulting in distinct morphology, thickness, and cross-linking degree of active layer. The active layer with sparse bead-like wrinkles on the smooth surface of support layer casted at HC = 65% showed the highest water permeability [26.9 (L/m2 h MPa)] and considerable low salt permeability [0.0390 (L/m2 h)]. It was found that the water flux of FO-65 was 27% and 46% higher than that of FO-80 in AL-DS and AL-FS mode, respectively, and the salt rejection was as high as 98%. Our work highlighted the importance of considering the effect of atmosphere humidity during casting when design an FO membrane for appropriate performance.

  17. Domestic wastewater treatment by forward osmosis-membrane distillation (FO-MD) integrated system.

    Science.gov (United States)

    Li, Jie; Hou, Deyin; Li, Kuiling; Zhang, Yong; Wang, Jun; Zhang, Xiwang

    2018-03-01

    In this study, real domestic wastewater treatment by forward osmosis-membrane distillation (FO-MD) integrated system was investigated in laboratory scale. The integrated membrane system presented a good separation performance and the removal efficiency of most contaminants in the domestic wastewater was higher than 90%. High molecular weight contaminants were completely removed, while a few low molecular weight contaminants permeated through the membrane. The FO membrane fouling layer mainly consisted of organic substances like polysaccharides and proteins, and was very loose and could be effectively removed by rinsing the membrane surface with tap water. By comparison, the MD membrane fouling was mainly induced by inorganic salts and was not as severe as that of the FO membrane. During 120 h continuous operation, the FO-MD integrated system exhibited satisfying performance stability and maintained a high water yield and high product water quality. The results indicated the potential of the FO-MD integrated system for municipal wastewater treatment in coastal cities, water purification and desalination.

  18. Comparison of methods used in European countries to assess buildings' condition

    NARCIS (Netherlands)

    Vilhena, A.; Costa Branco De Oliveira Pedro, J.A.; De Brito, J.

    2011-01-01

    This paper presents a comparative analysis of methods used in European countries to assess buildings’ condition. The following methods were compared: a Portuguese method to assess buildings condition, an English housing health and safety rating system, a French method to assess buildings that may be

  19. From the new Austrian tunneling method to the geoengineering condition evaluation and dynamic controlling method

    Directory of Open Access Journals (Sweden)

    Yanjun Shang

    2014-08-01

    Full Text Available The new Austrian tunneling method (NATM is widely applied in design and construction of underground engineering projects. When the type and distribution of unfavorable geological bodies (UGBs associated with their influences on geoengineering are complicated or unfortunately are overlooked, we should pay more attentions to internal features of rocks grades IV and V (even in local but mostly controlling zones. With increasing attentions to the characteristics, mechanism and influences of engineering construction-triggered geohazards, it is crucial to fully understand the disturbance of these geohazards on project construction. A reasonable determination method in construction procedure, i.e. the shape of working face, the type of engineering support and the choice of feasible procedure, should be considered in order to mitigate the construction-triggered geohazards. Due to their high sensitivity to groundwater and in-situ stress, various UGBs exhibit hysteretic nature and failure modes. To give a complete understanding on the internal causes, the emphasis on advanced comprehensive geological forecasting and overall reinforcement treatment is therefore of more practical significance. Comprehensive evaluation of influential factors, identification of UGB, and measures of discontinuity dynamic controlling comprises the geoengineering condition evaluation and dynamic controlling method. In a case of a cut slope, the variations of UGBs and the impacts of key environmental factors are presented, where more severe construction-triggered geohazards emerged in construction stage than those predicted in design and field investigation stages. As a result, the weight ratios of different influential factors with respect to field investigation, design and construction are obtained.

  20. Produced Water Treatment Using the Switchable Polarity Solvent Forward Osmosis (SPS FO) Desalination Process: Preliminary Engineering Design Basis

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Daniel; Adhikari, Birendra; Orme, Christopher; Wilson, Aaron

    2016-05-01

    Switchable Polarity Solvent Forward Osmosis (SPS FO) is a semi-permeable membrane-based water treatment technology. INL is currently advancing SPS FO technology such that a prototype unit can be designed and demonstrated for the purification of produced water from oil and gas production operations. The SPS FO prototype unit will used the thermal energy in the produced water as a source of process heat, thereby reducing the external process energy demands. Treatment of the produced water stream will reduce the volume of saline wastewater requiring disposal via injection, an activity that is correlated with undesirable seismic events, as well as generate a purified product water stream with potential beneficial uses. This paper summarizes experimental data that has been collected in support of the SPS FO scale-up effort, and describes how this data will be used in the sizing of SPS FO process equipment. An estimate of produced water treatment costs using the SPS FO process is also provided.

  1. Variability study of foF2 for an equatorial station

    International Nuclear Information System (INIS)

    Adeniyi, J.O.; Radicella, S.M.; Adimula, I.A.

    1994-08-01

    The deviation of hourly values of foF 2 from the monthly median values was used to study the variability of foF 2 . The study was done for the period of high and low solar activity. Generally the range of variation of the deviation is not dependent on solar activity. There is a tendency for positive deviation to occur on magnetically disturbed days and for negative deviation to occur on quiet days. The magnitude of the deviation does not depend on whether the day is disturbed or quiet. The correlation between Ap index and deviation of foF 2 from the median value is generally poor. THe range of deviation at night is usually higher than that of the daytime for the period of high solar activity. Some seasonal effect were also observed on the deviation. (author). 4 refs, 5 figs, 3 tabs

  2. Efficiently combining water reuse and desalination through Forward Osmosis-Reverse Osmosis (FO-RO) hybrids: a critical review

    OpenAIRE

    Blandin, G.; Verliefde, A.R.D.; Comas, J.; Rodriguez-Roda, I.; Le-Clech, P.

    2016-01-01

    Forward osmosis (FO) is a promising membrane technology to combine seawater desalination and water reuse. More specifically, in a FO-reverse osmosis (RO) hybrid process, high quality water recovered from the wastewater stream is used to dilute seawater before RO treatment. As such, lower desalination energy needs and/or water augmentation can be obtained while delivering safe water for direct potable reuse thanks to the double dense membrane barrier protection. Typically, FO-RO hybrid can be ...

  3. Evaluating biomethane production from anaerobic mono- and co-digestion of food waste and floatable oil (FO) skimmed from food waste.

    Science.gov (United States)

    Meng, Ying; Li, Sang; Yuan, Hairong; Zou, Dexun; Liu, Yanping; Zhu, Baoning; Chufo, Akiber; Jaffar, Muhammad; Li, Xiujin

    2015-06-01

    Batch anaerobic digestion was employed to investigate the performance of the floatable oil (FO) skimmed from food waste (FW) and the effect of different FO concentrations (5, 10, 20, 30, 40 and 50g/L) on biomethane production and system stability. FO and FO+FW were mono-digested and co-digested. The results showed that FO and FO+FW could be well anaerobically converted to biomethane in appropriate loads. For the mono-digestions of FO, the biomethane yield, TS and VS reduction achieved 607.7-846.9mL/g, 69.7-89% and 84.5-92.8%, respectively, when FO concentration was 5-40g/L. But the mono-digestion appeared instability when FO concentration was 50g/L. For the co-digestions of FW+FO, TS and VS reductions reached 70.7-86.1% and 87.5-91.4%, respectively, when FO concentration was 5-30g/L. However, the inhibition occurred when FO concentrations increased to 40-50g/L. The maximal FO loads of 40g/L and 30g/L were hence suggested for efficient mono-digestions and co-digestions of FO and FO+FW. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Förebyggande och rehabilitering av Osgood- Schlatter och Sinding-Larsen−Johanssons syndrom : Utformande av en handbok

    OpenAIRE

    Karenko, Sofia

    2016-01-01

    Detta arbete är ett praktiskt inriktat examensarbete där slutprodukten är en handbok med ett förebyggande och rehabiliterande träningsprogram för Osgood-Schlatter och Sinding-Larsen–Johanssons syndrom (SLJ). Syftet med arbetet är att öka kunskapen om syndromen och utforma ett träningsprogram som kan användas vid förebyggande och rehabiliteringen av dessa. Arbetet bygger på Vilkka och Airaksinens modell för praktiskt inriktat examensarbete som beskrivs i boken Toiminnallinen opinn...

  5. BioFoV - An open platform for forensic video analysis and biometric data extraction

    DEFF Research Database (Denmark)

    Almeida, Miguel; Correia, Paulo Lobato; Larsen, Peter Kastmand

    2016-01-01

    to tailor-made software, based on state of art knowledge in fields such as soft biometrics, gait recognition, photogrammetry, etc. This paper proposes an open and extensible platform, BioFoV (Biometric Forensic Video tool), for forensic video analysis and biometric data extraction, aiming to host some...... of the developments that researchers come up with for solving specific problems, but that are often not shared with the community. BioFoV includes a simple to use Graphical User Interface (GUI), is implemented with open software that can run in multiple software platforms, and its implementation is publicly available....

  6. Condition Assessment for Wastewater Pipes: Method for Assessing Cracking and Surface Damage of Concrete Pipes

    OpenAIRE

    Hauge, Petter

    2013-01-01

    The objective of the Master Thesis has been to provide an improved method for condition assessment, which will give a better correlation between Condition class and actual Condition of concrete pipes with cracking and/or surface damages. Additionally improvement of the characterization of cracking (SR) and surface (KO) damages was a sub goal.Based on the findings described in my Thesis and my Specialization Project (Hauge 2012), I recommend that the Norwegian condition assessment method based...

  7. Unusual nighttime impulsive foF2 enhancements at low latitudes: Phenomenology and possible explanations

    Science.gov (United States)

    Perna, L.; Pezzopane, M.; Zuccheretti, E.; Fagundes, P. R.; de Jesus, R.; Cabrera, M. A.; Ezquer, R. G.

    2014-08-01

    This paper is focused on unusual nighttime impulsive electron density enhancements that are rarely observed at low latitudes on a wide region of South America, under quiet and medium/high geomagnetic conditions. The phenomenon under investigation is very peculiar because besides being of brief duration, it is characterized by a pronounced compression of the ionosphere. The phenomenon was studied and analyzed using both the F2 layer critical frequency (foF2) and the virtual height of the base of the F region (h‧F) values recorded at five ionospheric stations widely distributed in space, namely: Jicamarca (-12.0°, -76.8°, magnetic latitude -2.0°), Peru; Sao Luis (-2.6°, -44.2°, magnetic latitude +6.2°), Cachoeira Paulista (-22.4°, -44.6°, magnetic latitude -13.4°), and São José dos Campos (-23.2°, -45.9°, magnetic latitude -14.1°), Brazil; Tucumán (-26.9°, -65.4°, magnetic latitude -16.8°), Argentina. In a more restricted region over Tucumán, the phenomenon was also investigated by the total electron content (TEC) maps computed by using measurements from 12 GPS receivers. A detailed analysis of isoheight ionosonde plots suggests that traveling ionospheric disturbances (TIDs) caused by gravity wave (GW) propagation could play a significant role in causing the phenomenon both for quiet and for medium/high geomagnetic activity; in the latter case however a recharging of the fountain effect, due to electric fields penetrating from the magnetosphere, joins the TID propagation and plays an as much significant role in causing impulsive electron density enhancements.

  8. Status of GRACE-FO accelerometers and of the future accelerometer development for next gravity missions

    Science.gov (United States)

    Liorzou, Françoise; Huynh, Phuong-Anh; Boulanger, Damien; Lebat, Vincent; Foulon, Bernard; Christophe, Bruno

    2017-04-01

    The GRACE FO mission, led by the JPL (Jet Propulsion Laboratory) and GFZ (GeoForschungsZentrum), is an Earth-orbiting gravity mission, continuation of the GRACE mission, which will produce an accurate model of the Earth's gravity field variation providing global climatic data during five years at least. Europe and US propose new gravity missions beyond GRACE-FO, with improving performance thanks to laser interferometry and better accelerometers. The poster will firstly present the status of GRACE-FO accelerometers which was delivered beginning of 2016, with the expected performance and the main test results. Then, the improvement of the accelerometer design for future gravity mission will be detailed. This new design is based on MicroSTAR configuration, a 3-axes ultra-sensitive accelerometer, with a cubic proof-mass which give, beyond the linear acceleration, the 3 angular accelerations for a better satellite attitude control. For linear acceleration, the performance will be improved by at least an order of magnitude with respect to GRACE-FO.

  9. FoCal – A high granularity electromagnetic calorimeter for forward direct photon measurements

    NARCIS (Netherlands)

    Zhang, C.

    2017-01-01

    The measurement of direct photon production at forward rapidity (y∼3−5) at the LHC provides access to the structure of protons and nuclei at very small values of fractional momentum (x∼10−5). FoCal, an extremely-high-granularity Forward Calorimeter covering 3.3<η<5.3 is proposed as a detector

  10. Oxalic acid complexes: Promising draw solutes for forward osmosis (FO) in protein enrichment

    KAUST Repository

    Ge, Qingchun

    2015-01-01

    Highly soluble oxalic acid complexes (OACs) were synthesized through a one-pot reaction. The OACs exhibit excellent performance as draw solutes in FO processes with high water fluxes and negligible reverse solute fluxes. Efficient protein enrichment was achieved. The diluted OACs can be recycled via nanofiltration and are promising as draw solutes.

  11. A novel TFC forward osmosis (FO) membrane supported by polyimide (PI) microporous nanofiber membrane

    Science.gov (United States)

    Chi, Xiang-Yu; Zhang, Ping-Yun; Guo, Xue-Jiao; Xu, Zhen-Liang

    2018-01-01

    A novel interfacial polymerization (IP) procedure on polyimide (PI) microporous nanofiber membrane support with mean pore size 1.27 μm was reported. Using m-phenylenediamine (MPD) as aqueous phase monomer, trimesoyl chloride (TMC) as organic phase monomer, ethanol as aqueous phase co-solvent, thin-film composite (TFC) forward osmosis (FO) membrane was fabricated by two IP procedures. The first IP procedure with the unconventional order (ie, the membrane was immersed in the TMC organic phase first, then in the co-solvent ethanol-water MPD aqueous phase) was used to diminish the pore size of PI microporous nanofiber membrane support for the formation of the polyamide layer. The secondary IP procedure was employed to form the relatively dense polyamide layer with conventional order (ie, the membrane was immersed in the co-solvent ethanol-water MPD aqueous phase first, then in the TMC organic phase). The experimental results showed that higher ethanol concentration led to the relatively higher pure water permeability in RO process and osmotic water flux in FO process, whereas NaCl rejection in RO process decreased and reverse salt flux increased. The specific salt flux (Js/Jv) of TFC FO PI nanofiber membrane (PIN-2-4) could be as low as 0.095 g/L in FO mode. These results could be attributed to influence of the addition of ethanol into aqueous phase on the surface morphology, hydrophilicity and polyamide layer structure.

  12. Chemical treatment of commercial reverse osmosis membranes for use in FO

    Science.gov (United States)

    Commercially available reverse osmosis (RO) membranes – SW30HR, BW30, and AG – were chemically treated for use in forward osmosis (FO). Nitric acid, phosphoric acid, sulfuric acid, ethanol, and ethanol–acid–water ternary solutions were employed for the treatment. All three membra...

  13. Real-time ligation chain reaction for DNA quantification and identification on the FO-SPR.

    Science.gov (United States)

    Knez, Karel; Spasic, Dragana; Delport, Filip; Lammertyn, Jeroen

    2015-05-15

    Different assays have been developed in the past years to meet point-of-care diagnostic tests requirements for fast and sensitive quantification and identification of targets. In this paper, we developed the ligation chain reaction (LCR) assay on the Fiber Optic Surface Plasmon Resonance (FO-SPR) platform, which enabled simultaneous quantification and cycle-to-cycle identification of DNA during amplification. The newly developed assay incorporated FO-SPR DNA melting assay, previously developed by our group. This required establishment of several assay parameters, including buffer ionic strength and thermal ramping speed as these parameters both influence the ligation enzyme performance and the hybridization yield of the gold nanoparticles (Au NPs) on the FO-SPR sensor. Quantification and identification of DNA targets was achieved over a wide concentration range with a calibration curve spanning 7 orders of magnitude and LOD of 13.75 fM. Moreover, the FO-SPR LCR assay could discriminate single nucleotide polymorphism (SNPs) without any post reaction analysis, featuring thus all the essential requirements of POC tests. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. KORELASI PENGGUNAAN BAHASA INGGRIS DALAM PENAMAAN FACTORY OUTLET (FO DI BANDUNG TERHADAP KEPUTUSAN PEMBELIAN

    Directory of Open Access Journals (Sweden)

    Gartika Rahmasari

    2016-03-01

        Abstrak - Bahasa Inggris merupakan bahasa yang memiliki prestise atau kedudukan yang tinggi, bahkan di Indonesia yang memiliki bahasa Indonesia sebagai bahasa nasional. Bahasa Inggris sebagai bahasa internasional mendapatkan apresiasi lebih tinggi dibandingkan dengan bahasa Indonesia, khususnya di bidang pariwisata. Bandung sebagai salah satu tujuan pariwisata, khususnya wisata kuliner dan tujuan belanja, tidak terkecuali mendapat pengaruh yang besar dalam hal penggunaan bahasa Inggris. Hal ini dapat dilihat dari penggunaan sejumlah nama Factory Outlet yang ada di Bandung, yang hampir sebagian besar menggunakan bahasa Ingris atau serapan bahasa Inggris sebagai “brand” atau nama yang digunakan oleh Factory Outlet yang tersebar di seluruh Bandung. Jurnal ini merupakan study literatur yang meneliti tentang hubungan penggunaan bahasa Asing dalam nama Factory Outlet  (FO terhadap keputusan pembelian. Yang menjadi responden yang diteliti dalam penelitian ini adalah mahasiswa Ilmu Komunikasi, Universitas Telkom sebanyak 55 responden, dengan rentang usia 17-20 tahun. Dari hasil penelitian, diketahui bahwa secara umum, penggunaan bahasa Inggris dalam penamaan Factory Outlet (FO mempengaruhi keputusan responden untuk berbelanja ke FO tersebut.   Kata Kunci: Keputusan Pembelian, Factory Outlet, FO, Bahasa Inggris.

  15. Determination of the equilibrium fO2 in bulk samples of H, L, and LL ordinary chondrites by solid-state electrochemistry

    Science.gov (United States)

    Osadchii, Valentin O.; Fedkin, Mark V.; Osadchii, Evgeniy G.

    2017-10-01

    High-temperature solid-state electrochemistry techniques (EMF method) were used to measure the oxygen fugacity (fO2) of the ordinary chondrites Ochansk (H4), Savtschenskoje (LL4), Elenovka (L5), Vengerovo (H5), and Kharkov (L6). The fO2 results are presented in the form of the following equations: logfO2>(Ochansk>)=>(9.39±1.64>)->(3.124∓0.191>)·104·T-1 1070/K(Vengerovo>)=>(6.86±1.73>)->(2.870∓0.196>)·104·T-1 1050/K(Elenovka>)=>(8.37±1.10>)->(3.005∓0.124>)·104·T-1 1050/K(Savtschenskoje>)=>(11.36±0.85>)->(3.289∓0.099>)·104·T-1 1070/K(Kharkov>)=>(7.80±0.44>)->(2.930∓0.050>)·104·T-1 1050/K 1200 K, becomes more reduced than Kharkov (L6) or Elenovka (L5). Measured oxygen fugacity values of meteorites fall within (0.1-1.0)·log fO2 of one another. The possible explanation of discrepancies between measured and calculated values is discussed.

  16. Effect of salinity and temperature on treatment of concentrated wastewater from RO by FO-MD

    Science.gov (United States)

    Zhou, Yingru; Huang, Manhong; Deng, Qian

    2018-02-01

    In this study the appropriate temperature of the membrane distillation (MD) hot side (the permeation flux of MD was controlled by adjusting the hot side temperature) was selected according to the water flux of FO process so that the water transfer rate on both sides of FO and MD was consistent and the FO-MD process could be stable operation. When the salt concentration of feed solution was 30, 55, 80 and 100 g/L, the desalination rates changed little, which were 99.1%, 98.4%, 98.9% and 98.7%, respectively. The removal rate of COD was 93.8%, 94.2%, 91.6% and 92.7% which also changed little like the desalination rates. The removal rate of chromaticity increased with the increase of salinity, which attained 96.6%, 97.0%, 97.2% and 97.9%, respectively. This study proved that salinity of the feed solution affected little on the removal rate of contaminants but great on the water flux, with the increase of salinity from 30 to 100 g/L, the water flux was 6.05, 4.81, 4.33 and 3.87 LMH with the appropriate temperature (67.5±0.5, 64.5±0.5, 62.5±0.5 and 60.5±0.5 °C) of MD hot side. In a word, FO-MD was first used to treat the high salinity RO water with over 30 g/L total dissolved solids (TDS), FO-MD was a promising new process for high salinity wastewater treatment, and the hybrid system can solve the problem of lower draw solution concentration, and the high-quality production water will be obtained directly by this hybrid system with low membrane fouling tendency.

  17. Real-time Continuous Assessment Method for Mental and Physiological Condition using Heart Rate Variability

    Science.gov (United States)

    Yoshida, Yutaka; Yokoyama, Kiyoko; Ishii, Naohiro

    It is necessary to monitor the daily health condition for preventing stress syndrome. In this study, it was proposed the method assessing the mental and physiological condition, such as the work stress or the relaxation, using heart rate variability at real time and continuously. The instantanuous heart rate (HR), and the ratio of the number of extreme points (NEP) and the number of heart beats were calculated for assessing mental and physiological condition. In this method, 20 beats heart rate were used to calculate these indexes. These were calculated in one beat interval. Three conditions, which are sitting rest, performing mental arithmetic and watching relaxation movie, were assessed using our proposed algorithm. The assessment accuracies were 71.9% and 55.8%, when performing mental arithmetic and watching relaxation movie respectively. In this method, the mental and physiological condition was assessed using only 20 regressive heart beats, so this method is considered as the real time assessment method.

  18. Low energy costs of F1Fo ATP synthase reversal in colon carcinoma cells deficient in mitochondrial complex IV.

    Science.gov (United States)

    Zhdanov, Alexander V; Andreev, Dmitry E; Baranov, Pavel V; Papkovsky, Dmitri B

    2017-05-01

    Mitochondrial polarisation is paramount for a variety of cellular functions. Under ischemia, mitochondrial membrane potential (ΔΨm) and proton gradient (ΔpH) are maintained via a reversal of mitochondrial F1Fo ATP synthase (mATPase), which can rapidly deplete ATP and drive cells into energy crisis. We found that under normal conditions in cells with disassembled cytochrome c oxidase complex (COX-deficient HCT116), mATPase maintains ΔΨm at levels only 15-20% lower than in WT cells, and for this utilises relatively little ATP. For a small energy expenditure, mATPase enables mitochondrial ΔpH, protein import, Ca 2+ turnover, and supports free radical detoxication machinery enlarged to protect the cells from oxidative damage. Whereas in COX-deficient cells the main source of ATP is glycolysis, the ΔΨm is still maintained upon inhibition of the adenine nucleotide translocators with bongkrekic acid and carboxyatractyloside, indicating that the role of ANTs is redundant, and matrix substrate level phosphorylation alone or in cooperation with ATP-Mg/P i carriers can continuously support the mATPase activity. Intriguingly, we found that mitochondrial complex III is active, and it contributes not only to free radical production, but also to ΔΨm maintenance and energy budget of COX-deficient cells. Overall, this study demonstrates that F1Fo ATP synthase can support general mitochondrial and cellular functions, working in extremely efficient 'energy saving' reverse mode and flexibly recruiting free radical detoxication and ATP producing / transporting pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. conditions

    Directory of Open Access Journals (Sweden)

    M. Venkatesulu

    1996-01-01

    Full Text Available Solutions of initial value problems associated with a pair of ordinary differential systems (L1,L2 defined on two adjacent intervals I1 and I2 and satisfying certain interface-spatial conditions at the common end (interface point are studied.

  20. Cognitive Artificial Intelligence Method for Interpreting Transformer Condition Based on Maintenance Data

    Directory of Open Access Journals (Sweden)

    Karel Octavianus Bachri

    2017-07-01

    Full Text Available A3S(Arwin-Adang-Aciek-Sembiring is a method of information fusion at a single observation and OMA3S(Observation Multi-time A3S is a method of information fusion for time-series data. This paper proposes OMA3S-based Cognitive Artificial-Intelligence method for interpreting Transformer Condition, which is calculated based on maintenance data from Indonesia National Electric Company (PLN. First, the proposed method is tested using the previously published data, and then followed by implementation on maintenance data. Maintenance data are fused to obtain part condition, and part conditions are fused to obtain transformer condition. Result shows proposed method is valid for DGA fault identification with the average accuracy of 91.1%. The proposed method not only can interpret the major fault, it can also identify the minor fault occurring along with the major fault, allowing early warning feature. Result also shows part conditions can be interpreted using information fusion on maintenance data, and the transformer condition can be interpreted using information fusion on part conditions. The future works on this research is to gather more data, to elaborate more factors to be fused, and to design a cognitive processor that can be used to implement this concept of intelligent instrumentation.

  1. A Nitsche cut finite element method for the Oseen problem with general Navier boundary conditions

    Science.gov (United States)

    Winter, M.; Schott, B.; Massing, A.; Wall, W. A.

    2018-03-01

    In this work a Nitsche-based imposition of generalized Navier conditions on cut meshes for the Oseen problem is presented. Other methods from literature dealing with the generalized Navier condition impose this condition by means of substituting the tangential Robin condition in a classical Galerkin way. These methods work fine for a large slip length coefficient but lead to conditioning and stability issues when it approaches zero. We introduce a novel method for the weak imposition of the generalized Navier condition which remains well-posed and stable for arbitrary choice of slip length, including zero. The method proposed here builds on the formulation done by [1]. They impose a Robin condition for the Poisson problem by means of Nitsche's method for an arbitrary combination of the Dirichlet and Neumann parts of the condition. The analysis conducted for the proposed method is done in a similar fashion as in [2], but is done here for a more general type of boundary condition. The analysis proves stability for all flow regimes and all choices of slip lengths. Also an L2-optimal estimate for the velocity error is shown, which was not conducted in the previously mentioned work. A numerical example is carried out for varying slip lengths to verify the robustness and stability of the method with respect to the choice of slip length. Even though proofs and formulations are presented for the more general case of an unfitted grid method, they can easily be reduced to the simpler case of a boundary-fitted grid with the removal of the ghost-penalty stabilization terms.

  2. A method for aggregating external operating conditions in multi-generation system optimization models

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Münster, Marie; Ensinas, Adriano Viana

    2016-01-01

    This paper presents a novel, simple method for reducing external operating condition datasets to be used in multi-generation system optimization models. The method, called the Characteristic Operating Pattern (CHOP) method, is a visually-based aggregation method that clusters reference data based...... on parameter values rather than time of occurrence, thereby preserving important information on short-term relations between the relevant operating parameters. This is opposed to commonly used methods where data are averaged over chronological periods (months or years), and extreme conditions are hidden...... in the averaged values. The CHOP method is tested in a case study where the operation of a fictive Danish combined heat and power plant is optimized over a historical 5-year period. The optimization model is solved using the full external operating condition dataset, a reduced dataset obtained using the CHOP...

  3. A demonstration of arm-locking for LISA using the GRACE-FO Laser Ranging Instrument

    Science.gov (United States)

    Thorpe, Ira; McKenzie, Kirk; Sutton, Andrew

    2015-04-01

    The mitigation of laser frequency noise is a key challenge for the design of space-based interferometric gravitational wave detectors such as the Laser Interferometer Space Antenna (LISA) and its derivatives. Arm locking is novel technique of stabilizing the laser frequency using the LISA arms that has been studied through simulations and in the laboratory. The Laser Ranging Instrument (LRI) on the upcoming GRACE-FO geodesy mission provides an opportunity to perform an on-orbit demonstration of arm-locking in a configuration that is representative of LISA in many aspects. In this talk, I will describe a potential arm-locking experiment for GRACE-FO and present preliminary results from time-domain simulations being used to refine the proposed experiment design.

  4. Efficiently Combining Water Reuse and Desalination through Forward Osmosis—Reverse Osmosis (FO-RO Hybrids: A Critical Review

    Directory of Open Access Journals (Sweden)

    Gaetan Blandin

    2016-07-01

    Full Text Available Forward osmosis (FO is a promising membrane technology to combine seawater desalination and water reuse. More specifically, in a FO-reverse osmosis (RO hybrid process, high quality water recovered from the wastewater stream is used to dilute seawater before RO treatment. As such, lower desalination energy needs and/or water augmentation can be obtained while delivering safe water for direct potable reuse thanks to the double dense membrane barrier protection. Typically, FO-RO hybrid can be a credible alternative to new desalination facilities or to implementation of stand-alone water reuse schemes. However, apart from the societal (public perception of water reuse for potable application and water management challenges (proximity of wastewater and desalination plants, FO-RO hybrid has to overcome technical limitation such as low FO permeation flux to become economically attractive. Recent developments (i.e., improved FO membranes, use of pressure assisted osmosis, PAO demonstrated significant improvement in water flux. However, flux improvement is associated with drawbacks, such as increased fouling behaviour, lower rejection of trace organic compounds (TrOCs in PAO operation, and limitation in FO membrane mechanical resistance, which need to be better considered. To support successful implementation of FO-RO hybrid in the industry, further work is required regarding up-scaling to apprehend full-scale challenges in term of mass transfer limitation, pressure drop, fouling and cleaning strategies on a module scale. In addition, refined economics assessment is expected to integrate fouling and other maintenance costs/savings of the FO/PAO-RO hybrid systems, as well as cost savings from any treatment step avoided in the water recycling.

  5. Efficiently Combining Water Reuse and Desalination through Forward Osmosis—Reverse Osmosis (FO-RO) Hybrids: A Critical Review

    Science.gov (United States)

    Blandin, Gaetan; Verliefde, Arne R.D.; Comas, Joaquim; Rodriguez-Roda, Ignasi; Le-Clech, Pierre

    2016-01-01

    Forward osmosis (FO) is a promising membrane technology to combine seawater desalination and water reuse. More specifically, in a FO-reverse osmosis (RO) hybrid process, high quality water recovered from the wastewater stream is used to dilute seawater before RO treatment. As such, lower desalination energy needs and/or water augmentation can be obtained while delivering safe water for direct potable reuse thanks to the double dense membrane barrier protection. Typically, FO-RO hybrid can be a credible alternative to new desalination facilities or to implementation of stand-alone water reuse schemes. However, apart from the societal (public perception of water reuse for potable application) and water management challenges (proximity of wastewater and desalination plants), FO-RO hybrid has to overcome technical limitation such as low FO permeation flux to become economically attractive. Recent developments (i.e., improved FO membranes, use of pressure assisted osmosis, PAO) demonstrated significant improvement in water flux. However, flux improvement is associated with drawbacks, such as increased fouling behaviour, lower rejection of trace organic compounds (TrOCs) in PAO operation, and limitation in FO membrane mechanical resistance, which need to be better considered. To support successful implementation of FO-RO hybrid in the industry, further work is required regarding up-scaling to apprehend full-scale challenges in term of mass transfer limitation, pressure drop, fouling and cleaning strategies on a module scale. In addition, refined economics assessment is expected to integrate fouling and other maintenance costs/savings of the FO/PAO-RO hybrid systems, as well as cost savings from any treatment step avoided in the water recycling. PMID:27376337

  6. Efficiently Combining Water Reuse and Desalination through Forward Osmosis-Reverse Osmosis (FO-RO) Hybrids: A Critical Review.

    Science.gov (United States)

    Blandin, Gaetan; Verliefde, Arne R D; Comas, Joaquim; Rodriguez-Roda, Ignasi; Le-Clech, Pierre

    2016-07-01

    Forward osmosis (FO) is a promising membrane technology to combine seawater desalination and water reuse. More specifically, in a FO-reverse osmosis (RO) hybrid process, high quality water recovered from the wastewater stream is used to dilute seawater before RO treatment. As such, lower desalination energy needs and/or water augmentation can be obtained while delivering safe water for direct potable reuse thanks to the double dense membrane barrier protection. Typically, FO-RO hybrid can be a credible alternative to new desalination facilities or to implementation of stand-alone water reuse schemes. However, apart from the societal (public perception of water reuse for potable application) and water management challenges (proximity of wastewater and desalination plants), FO-RO hybrid has to overcome technical limitation such as low FO permeation flux to become economically attractive. Recent developments (i.e., improved FO membranes, use of pressure assisted osmosis, PAO) demonstrated significant improvement in water flux. However, flux improvement is associated with drawbacks, such as increased fouling behaviour, lower rejection of trace organic compounds (TrOCs) in PAO operation, and limitation in FO membrane mechanical resistance, which need to be better considered. To support successful implementation of FO-RO hybrid in the industry, further work is required regarding up-scaling to apprehend full-scale challenges in term of mass transfer limitation, pressure drop, fouling and cleaning strategies on a module scale. In addition, refined economics assessment is expected to integrate fouling and other maintenance costs/savings of the FO/PAO-RO hybrid systems, as well as cost savings from any treatment step avoided in the water recycling.

  7. What Can be Expected from the GRACE-FO Laser Ranging Interferometer for Earth Science Applications?

    OpenAIRE

    Frank Flechtner; Karl Neumayer; Christoph Dahle; H. Dobslaw; Elisa Fagiolini; J.-C. Raimondo; A. Güntner

    2016-01-01

    The primary objective of the Gravity Recovery and Climate Experiment Follow-on (GRACE-FO) satellite mission is to continue the GRACE time series of global monthly gravity field models. For this, evolved versions of the GRACE microwave instrument (MWI), GPS-receiver, and accelerometer will be used. A secondary objective is to demonstrate the effectiveness of a laser ranging interferometer (LRI) in improving the low-low satellite-to-satellite tracking measurement performance. In ...

  8. Development and Release of a GRACE-FO "Grand Simulation" Data Set by JPL

    Science.gov (United States)

    Fahnestock, E.; Yuan, D. N.; Wiese, D. N.; McCullough, C. M.; Harvey, N.; Sakumura, C.; Paik, M.; Bertiger, W. I.; Wen, H. Y.; Kruizinga, G. L. H.

    2017-12-01

    The GRACE-FO mission, to be launched early in 2018, will require several stages of data processing to be performed within its Science Data System (SDS). In an effort to demonstrate effective implementation and inter-operation of this level 1, 2, and 3 data processing, and to verify its combined ability to recover a truth Earth gravity field to within top-level requirements, the SDS team has performed a system test which it has termed the "Grand Simulation". This process starts with iteration to converge on a mutually consistent integrated truth orbit, non-gravitational acceleration time history, and spacecraft attitude time history, generated with the truth models for all elements of the integrated system (geopotential, both GRACE-FO spacecraft, constellation of GPS spacecraft, etc.). Level 1A data products are generated and then the GPS time to onboard receiver time clock error is introduced into those products according to a realistic truth clock offset model. The various data products are noised according to current best estimate noise models, and then some are used within a precision orbit determination and clock offset estimation/recovery process. Processing from level 1A to level 1B data products uses the recovered clock offset to correct back to GPS time, and performs gap-filling, compression, etc. This exercises nearly all software pathways intended for processing actual GRACE-FO science data. Finally, a monthly gravity field is recovered and compared against the truth background field. In this talk we briefly summarize the resulting performance vs. requirements, and lessons learned in the system test process. Finally, we provide information for use of the level 1B data set by the general community for gravity solution studies and software trials in anticipation of operational GRACE-FO data. ©2016 California Institute of Technology. Government sponsorship acknowledged.

  9. Imposition of Dirichlet Boundary Conditions in Element Free Galerkin Method through an Object-Oriented Implementation

    Directory of Open Access Journals (Sweden)

    Samira Hosseini

    Full Text Available Abstract One of the main drawbacks of Element Free Galerkin (EFG method is its dependence on moving least square shape functions which don’t satisfy the Kronecker Delta property, so in this method it’s not possible to apply Dirichlet boundary conditions directly. The aim of the present paper is to discuss different aspects of three widely used methods of applying Dirichlet boundary conditions in EFG method, called Lagrange multipliers, penalty method, and coupling with finite element method. Numerical simulations are presented to compare the results of these methods form the perspective of accuracy, convergence and computational expense. These methods have been implemented in an object oriented programing environment, called INSANE, and the results are presented and compared with the analytical solutions.

  10. Measuring method to impulse neutron scattering background in complicated ambient condition

    International Nuclear Information System (INIS)

    Tang Zhangkui; Peng Taiping; Tang Zhengyuan; Liu Hangang; Hu Mengchun; Fan Juan

    2004-01-01

    This paper introduced a measuring method and calculative formula about impulse neutron scattering background in complicated ambient condition. The experiment had been done in the lab, and the factors to affect measurement conclusion were analysised. (authors)

  11. A simple method of fitting ill-conditioned polynomials to data

    International Nuclear Information System (INIS)

    Buckler, A.N.; Lawrence, J.

    1979-04-01

    A very simple transformation of the independent variable x is shown to cure the ill-conditioning when some polynomial series are fitted to given Y values. Numerical examples are given to illustrate the power of the method. (author)

  12. Ogunleke, FO

    African Journals Online (AJOL)

    Chemical composition and microbial load of cheese produced using ginger, onion and bear berry. Abstract · Vol 12, No 2 (2014) - Articles Effects of inclusion of varying levels of three natural spices on the mineral composition and organoleptic properties of West African soft unripened cheese (“WARA”) Abstract. ISSN: 1597- ...

  13. Effect of surface conditioning methods on the microtensile bond strength of resin composite to composite after aging conditions.

    Science.gov (United States)

    Ozcan, Mutlu; Barbosa, Silvia Helena; Melo, Renata Marques; Galhano, Graziela Avila Prado; Bottino, Marco Antonio

    2007-10-01

    This study evaluated the effect of two different surface conditioning methods on the repair bond strength of a bis-GMA-adduct/bis-EMA/TEGDMA based resin composite after three aging conditions. Thirty-six composite resin blocks (Esthet X, Dentsply) were prepared (5 mm x 6 mm x 6 mm) and randomly assigned into three groups for aging process: (a) immersion in citric acid (pH 3.0 at 37 degrees C, 1 week) (CA); (b) boiling in water for 8h (BW) and (c) thermocycling (x5000, 5-55 degrees C, dwell time: 30s) (TC). After aging, the blocks were assigned to one of the following surface conditioning methods: (1) silica coating (30 microm SiO(x)) (CoJet, 3M ESPE)+silane (ESPE-Sil) (CJ), (2) phosphoric acid+adhesive resin (Single Bond, 3M ESPE) (PA). Resin composite (Esthet.X) was bonded to the conditioned substrates incrementally and light polymerized. The experimental groups formed were as follows: Gr1:CA+PA; Gr2:CA+CJ; Gr3:BW+PA; Gr4: BW+CJ; Gr5:TC+PA; Gr6: TC+CJ. The specimens were sectioned in two axes (x and y) with a diamond disc under coolant irrigation in order to obtain non-trimmed bar specimens (sticks, 10 mm x 1 mm x 1 mm) with 1 mm(2) of bonding area. The microtensile test was accomplished in a universal testing machine (crosshead speed: 0.5 mm min(-1)). The means and standard deviations of bond strength (MPa+/-S.D.) per group were as follows: Gr1: 25.5+/-10.3; Gr2: 46.3+/-10.1; Gr3: 21.7+/-7.1; Gr4: 52.3+/-15.1; Gr5: 16.1+/-5.1; Gr6, 49.6+/-13.5. The silica coated groups showed significantly higher mean bond values after all three aging conditions (presin-resin bond strength values compared to acid etching with phosphoric acid followed by adhesive resin applications. Thermocycling the composite substrates resulted in the lowest repair bond strength compared to citric acid challenge or boiling in water.

  14. Full scale simulation of MWI and LRI based GRACE-FO gravity models

    Science.gov (United States)

    Flechtner, Frank; Raimondo, Jean-Claude; Dobslaw, Henryk; Fagiolini, Elisa

    2014-05-01

    During 12 years of very successful operation in orbit, the US-German GRACE mission has demonstrated its outstanding capability to monitor mass motions in the Earth system with unprecedented accuracy and temporal resolution. These results have stimulated many novel research activities in hydrology, oceanography, glaciology, geophysics, and geodesy which also indicate that long term monitoring of such mass variations, possibly with improved spatial and temporal resolution, is a must for further understanding of phenomena such as ice mass los in Polar Regions and large glacier systems or the continental hydrological cycle. Due to the onboard battery situation, GRACE can likely not be operated further than 2015. Fortunately, a GRACE follow-on mission is currently being implemented jointly by JPL/NASA and GFZ and due for launch in August 2017. GRACE-FO will be based on GRACE heritage and lessons learnt during operation. Therefore, the prime SST (satellite-to-satellite tracking) instrument will be again the Microwave Ranging Instrument (MWI). Additionally, GRACE-FO will carry a Laser Ranging Interferometer (LRI) demonstrator which will have a factor of 10-50 improved SST measurement accuracy. We will present a multi-years full scale simulation based on realistic error assumptions for instrument noise and background models such as tidal and non-tidal mass variations. The results shall indicate what the users can expect in terms of precision and spatial and temporal resolution when using future GRACE-FO MWI and LRI based gravity models.

  15. The c-Ring of the F1FO-ATP Synthase: Facts and Perspectives.

    Science.gov (United States)

    Nesci, Salvatore; Trombetti, Fabiana; Ventrella, Vittoria; Pagliarani, Alessandra

    2016-04-01

    The F1FO-ATP synthase is the only enzyme in nature endowed with bi-functional catalytic mechanism of synthesis and hydrolysis of ATP. The enzyme functions, not only confined to energy transduction, are tied to three intrinsic features of the annular arrangement of c subunits which constitutes the so-called c-ring, the core of the membrane-embedded FO domain: (i) the c-ring constitution is linked to the number of ions (H(+) or Na(+)) channeled across the membrane during the dissipation of the transmembrane electrochemical gradient, which in turn determines the species-specific bioenergetic cost of ATP, the "molecular currency unit" of energy transfer in all living beings; (ii) the c-ring is increasingly involved in the mitochondrial permeability transition, an event linked to cell death and to most mitochondrial dysfunctions; (iii) the c subunit species-specific amino acid sequence and susceptibility to post-translational modifications can address antibacterial drug design according to the model of enzyme inhibitors which target the c subunits. Therefore, the simple c-ring structure not only allows the F1FO-ATP synthase to perform the two opposite tasks of molecular machine of cell life and death, but it also amplifies the enzyme's potential role as a drug target.

  16. Development and Demonstration of an Aerial Imagery Assessment Method to Monitor Changes in Restored Stream Condition

    Science.gov (United States)

    Fong, L. S.; Ambrose, R. F.

    2017-12-01

    Remote sensing is an excellent way to assess the changing condition of streams and wetlands. Several studies have measured large-scale changes in riparian condition indicators, but few have remotely applied multi-metric assessments on a finer scale to measure changes, such as those caused by restoration, in the condition of small riparian areas. We developed an aerial imagery assessment method (AIAM) that combines landscape, hydrology, and vegetation observations into one index describing overall ecological condition of non-confined streams. Verification of AIAM demonstrated that sites in good condition (as assessed on-site by the California Rapid Assessment Method) received high AIAM scores. (AIAM was not verified with poor condition sites.) Spearman rank correlation tests comparing AIAM and the field-based California Rapid Assessment Method (CRAM) results revealed that some components of the two methods were highly correlated. The application of AIAM is illustrated with time-series restoration trajectories of three southern California stream restoration projects aged 15 to 21 years. The trajectories indicate that the projects improved in condition in years following their restoration, with vegetation showing the most dynamic change over time. AIAM restoration trajectories also overlapped to different degrees with CRAM chronosequence restoration performance curves that demonstrate the hypothetical development of high-performing projects. AIAM has high potential as a remote ecological assessment method and effective tool to determine restoration trajectories. Ultimately, this tool could be used to further improve stream and wetland restoration management.

  17. Reinforced Concrete Bridge Deck Condition Assessment Methods Using Ground Penetrating Radar and Infrared Thermography

    OpenAIRE

    Nicole M. Martino

    2017-01-01

    Reinforced concrete bridge deck condition assessments primarily use visual inspection methods, where an inspector looks for and records locations of cracks, potholes, efflorescence and other signs of probable deterioration. Sounding is another technique used to diagnose the condition of a bridge deck, however this method listens for damage within the subsurface as the surface is struck with a hammer or chain. Even though extensive procedures are in place for using these inspection techniques,...

  18. Determination of Proton Flux and Conductance at pH 6.8 through Single Fo Sectors from Escherichia coli

    OpenAIRE

    Franklin, Michael J.; Brusilow, William S.A.; Woodbury, Dixon J.

    2004-01-01

    We have developed a mathematical model in concert with an assay that allows us to calculate proton (H+) flux and conductance through a single Fo of the F1Fo ATP synthase. Lipid vesicles reconstituted with just a few functional Fo from Escherichia coli were loaded with 250 mM K+ and suspended in a low K+ solution. The pH of the weakly buffered external solution was recorded during sequential treatment with the potassium ionophore valinomycin, the protonophore carbonyl cyanide 3-chlorophenylhyd...

  19. Cubic Hermite Collocation Method for Solving Boundary Value Problems with Dirichlet, Neumann, and Robin Conditions

    Directory of Open Access Journals (Sweden)

    Ishfaq Ahmad Ganaie

    2014-01-01

    Full Text Available Cubic Hermite collocation method is proposed to solve two point linear and nonlinear boundary value problems subject to Dirichlet, Neumann, and Robin conditions. Using several examples, it is shown that the scheme achieves the order of convergence as four, which is superior to various well known methods like finite difference method, finite volume method, orthogonal collocation method, and polynomial and nonpolynomial splines and B-spline method. Numerical results for both linear and nonlinear cases are presented to demonstrate the effectiveness of the scheme.

  20. A New Application of Support Vector Machine Method: Condition Monitoring and Analysis of Reactor Coolant Pump

    Science.gov (United States)

    Meng, Qinghu; Meng, Qingfeng; Feng, Wuwei

    2012-05-01

    Fukushima nuclear power plant accident caused huge losses and pollution and it showed that the reactor coolant pump is very important in a nuclear power plant. Therefore, to keep the safety and reliability, the condition of the coolant pump needs to be online condition monitored and fault analyzed. In this paper, condition monitoring and analysis based on support vector machine (SVM) is proposed. This method is just to aim at the small sample studies such as reactor coolant pump. Both experiment data and field data are analyzed. In order to eliminate the noise and useless frequency, these data are disposed through a multi-band FIR filter. After that, a fault feature selection method based on principal component analysis is proposed. The related variable quantity is changed into unrelated variable quantity, and the dimension is descended. Then the SVM method is used to separate different fault characteristics. Firstly, this method is used as a two-kind classifier to separate each two different running conditions. Then the SVM is used as a multiple classifier to separate all of the different condition types. The SVM could separate these conditions successfully. After that, software based on SVM was designed for reactor coolant pump condition analysis. This software is installed on the reactor plant control system of Qinshan nuclear power plant in China. It could monitor the online data and find the pump mechanical fault automatically.

  1. The Ritz Method for Boundary Problems with Essential Conditions as Constraints

    Directory of Open Access Journals (Sweden)

    Vojin Jovanovic

    2016-01-01

    Full Text Available We give an elementary derivation of an extension of the Ritz method to trial functions that do not satisfy essential boundary conditions. As in the Babuška-Brezzi approach boundary conditions are treated as variational constraints and Lagrange multipliers are used to remove them. However, we avoid the saddle point reformulation of the problem and therefore do not have to deal with the Babuška-Brezzi inf-sup condition. In higher dimensions boundary weights are used to approximate the boundary conditions, and the assumptions in our convergence proof are stated in terms of completeness of the trial functions and of the boundary weights. These assumptions are much more straightforward to verify than the Babuška-Brezzi condition. We also discuss limitations of the method and implementation issues that follow from our analysis and examine a number of examples, both analytic and numerical.

  2. Evaluating transmission electron microscopy as a method for assessing the condition of archaeological wool

    DEFF Research Database (Denmark)

    Scharff, Annemette Bruselius; Jørgensen, Lise Bolt

    2017-01-01

    Transmission electron microscopy (TEM) was investigated to clarify the applicability of the method for assessing the condition of archaeological textiles from waterlogged environments. A description and evaluation of the TEM protocol is presented and the method was tested on new and artificially...

  3. Effect of surface conditioning methods on the bond strength of luting cement to ceramics

    NARCIS (Netherlands)

    Ozcan, M; Vallittu, PK; Özcan, Mutlu; Vallittu, Pekka K.

    2003-01-01

    Objectives. This study evaluated the effect of three different surface conditioning methods on the bond strength of a Bis-GMA based luting cement to six commercial dental ceramics. Methods. Six disc shaped ceramic specimens (glass ceramics, glass infiltrated alumina, glass infiltrated zirconium

  4. Calculation of condition indices for road structures using a deduct points method

    CSIR Research Space (South Africa)

    Roux, MP

    2016-07-01

    Full Text Available ) and relevancy (R) rating. The DER-rating method has been included in the Draft TMH19 Manual for the Visual Assessment of Road Structures. The D, E, and R ratings are used to calculate condition indices for road structures. The method used is a deduct...

  5. Effect of Multi-condition Training and Speech Enhancement Methods on Spoofing Detection

    DEFF Research Database (Denmark)

    Yu, Hong; Sarkar, Achintya Kumar; Thomsen, Dennis Alexander Lehmann

    2016-01-01

    at different signal-to-noise ratios, and two mainstream speech enhancement methods, Wiener filtering and minimum mean-square error. The experimental results show that enhancement methods are not suitable for the spoofing detection task, as the spoofing detection accuracy will be reduced after speech...... enhancement. Multi-conditional training, however, shows potential at reducing error rates for spoofing detection....

  6. Concrete Condition Assessment Using Impact-Echo Method and Extreme Learning Machines

    Science.gov (United States)

    Zhang, Jing-Kui; Yan, Weizhong; Cui, De-Mi

    2016-01-01

    The impact-echo (IE) method is a popular non-destructive testing (NDT) technique widely used for measuring the thickness of plate-like structures and for detecting certain defects inside concrete elements or structures. However, the IE method is not effective for full condition assessment (i.e., defect detection, defect diagnosis, defect sizing and location), because the simple frequency spectrum analysis involved in the existing IE method is not sufficient to capture the IE signal patterns associated with different conditions. In this paper, we attempt to enhance the IE technique and enable it for full condition assessment of concrete elements by introducing advanced machine learning techniques for performing comprehensive analysis and pattern recognition of IE signals. Specifically, we use wavelet decomposition for extracting signatures or features out of the raw IE signals and apply extreme learning machine, one of the recently developed machine learning techniques, as classification models for full condition assessment. To validate the capabilities of the proposed method, we build a number of specimens with various types, sizes, and locations of defects and perform IE testing on these specimens in a lab environment. Based on analysis of the collected IE signals using the proposed machine learning based IE method, we demonstrate that the proposed method is effective in performing full condition assessment of concrete elements or structures. PMID:27023563

  7. Multiregion, multigroup collision probability method with white boundary condition for light water reactor thermalization calculations

    International Nuclear Information System (INIS)

    Ozgener, B.; Ozgener, H.A.

    2005-01-01

    A multiregion, multigroup collision probability method with white boundary condition is developed for thermalization calculations of light water moderated reactors. Hydrogen scatterings are treated by Nelkin's kernel while scatterings from other nuclei are assumed to obey the free-gas scattering kernel. The isotropic return (white) boundary condition is applied directly by using the appropriate collision probabilities. Comparisons with alternate numerical methods show the validity of the present formulation. Comparisons with some experimental results indicate that the present formulation is capable of calculating disadvantage factors which are closer to the experimental results than alternative methods

  8. Modern methods of surveyor observations in opencast mining under complex hydrogeological conditions.

    Science.gov (United States)

    Usoltseva, L. A.; Lushpei, V. P.; Mursin, VA

    2017-10-01

    The article considers the possibility of linking the modern methods of surveying security of open mining works to improve industrial safety in the Primorsky Territory, as well as their use in the educational process. Industrial Safety in the management of Surface Mining depends largely on the applied assessment methods and methods of stability of pit walls and slopes of dumps in the complex mining and hydro-geological conditions.

  9. The multipurpose industrial company’s competitiveness evaluation method for instable environmental conditions

    OpenAIRE

    Kuchina E.V.; Baeva D.A.

    2017-01-01

    The competitiveness evaluation method for industrial companies was created by authors and described in the article. This method allows considering specific features of contemporary economic conditions. There are two main features: Russian economy is under the external pressure, it instable and needs structural changes. The main advantage of the method is following: it can evaluate both the current and the perspective competitiveness of company considering the aim of increasing competitiveness...

  10. An FDTD method with FFT-accelerated exact absorbing boundary conditions

    KAUST Repository

    Sirenko, Kostyantyn

    2011-07-01

    An accurate and efficient finite-difference time-domain (FDTD) method for analyzing axially symmetric structures is presented. The method achieves its accuracy and efficiency using exact absorbing conditions (EACs) for terminating the computation domain and a blocked-FFT based scheme for accelerating the computation of the temporal convolutions present in non-local EACs. The method is shown to be especially useful in characterization of long-duration resonant wave interactions. © 2011 IEEE.

  11. The Biological Role of the ζ Subunit as Unidirectional Inhibitor of the F1FO-ATPase of Paracoccus denitrificans

    Directory of Open Access Journals (Sweden)

    Francisco Mendoza-Hoffmann

    2018-01-01

    Full Text Available The biological roles of the three natural F1FO-ATPase inhibitors, ε, ζ, and IF1, on cell physiology remain controversial. The ζ subunit is a useful model for deletion studies since it mimics mitochondrial IF1, but in the F1FO-ATPase of Paracoccus denitrificans (PdF1FO, it is a monogenic and supernumerary subunit. Here, we constructed a P. denitrificans 1222 derivative (PdΔζ with a deleted ζ gene to determine its role in cell growth and bioenergetics. The results show that the lack of ζ in vivo strongly restricts respiratory P. denitrificans growth, and this is restored by complementation in trans with an exogenous ζ gene. Removal of ζ increased the coupled PdF1FO-ATPase activity without affecting the PdF1FO-ATP synthase turnover, and the latter was not affected at all by ζ reconstitution in vitro. Therefore, ζ works as a unidirectional pawl-ratchet inhibitor of the PdF1FO-ATPase nanomotor favoring the ATP synthase turnover to improve respiratory cell growth and bioenergetics.

  12. Oxygen Buffering in High Pressure Solid Media Assemblies: New Approach Enabling Study of fO2 from IW-4 to IW+4.5

    Science.gov (United States)

    Righter, K.; Pando, K. M.; Ross, D. K.; Butterworth, A. L.; Gainsforth, Z.; Jilly-Rehak, C. E.; Westphal, A. J.

    2017-01-01

    Oxygen fugacity is an intensive parameter that controls some fundamental chemical and physical properties in planetary materials. In terrestrial magmas high fO2 promotes magnetite stability and low fO2 causes Fe-enrichment due to magnetite suppression. In lunar and asteroidal basalts, low fO2 can allow metal to be stable. Experimental studies will therefore be most useful if they are done at a specific and relevant fO2 for the samples under consideration. Control of fO2 in the solid media apparatus (piston cylinder multi-anvil) has relied on either sliding sensors or graphite capsule buffering, which are of limited application to the wide range of fO2 recorded in planetary or astromaterials. Here we describe a new approach that allows fO2 to be specified across a wide range of values relevant to natural samples.

  13. Photovoltaic module and array performance characterization methods for all system operating conditions

    Energy Technology Data Exchange (ETDEWEB)

    King, D.L.

    1996-12-31

    This paper provides new test methods and analytical procedures for characterizing the electrical performance of photovoltaic modules and arrays. The methods use outdoor measurements to provide performance parameters both at standard reporting conditions and for all operating conditions encountered by typical photovoltaic systems. Improvements over previously used test methods are identified, and examples of the successful application of the methodology are provided for crystalline- and amorphous-silicon modules and arrays. This work provides an improved understanding of module and array performance characteristics, and perhaps most importantly, a straight- forward yet rigorous model for predicting array performance at all operating conditions. For the first time, the influences of solar irradiance, operating temperature, solar spectrum, solar angle-of- incidence, and temperature coefficients are all addressed in a practical way that will benefit both designers and users of photovoltaics.

  14. WMAXC: a weighted maximum clique method for identifying condition-specific sub-network.

    Directory of Open Access Journals (Sweden)

    Bayarbaatar Amgalan

    Full Text Available Sub-networks can expose complex patterns in an entire bio-molecular network by extracting interactions that depend on temporal or condition-specific contexts. When genes interact with each other during cellular processes, they may form differential co-expression patterns with other genes across different cell states. The identification of condition-specific sub-networks is of great importance in investigating how a living cell adapts to environmental changes. In this work, we propose the weighted MAXimum clique (WMAXC method to identify a condition-specific sub-network. WMAXC first proposes scoring functions that jointly measure condition-specific changes to both individual genes and gene-gene co-expressions. It then employs a weaker formula of a general maximum clique problem and relates the maximum scored clique of a weighted graph to the optimization of a quadratic objective function under sparsity constraints. We combine a continuous genetic algorithm and a projection procedure to obtain a single optimal sub-network that maximizes the objective function (scoring function over the standard simplex (sparsity constraints. We applied the WMAXC method to both simulated data and real data sets of ovarian and prostate cancer. Compared with previous methods, WMAXC selected a large fraction of cancer-related genes, which were enriched in cancer-related pathways. The results demonstrated that our method efficiently captured a subset of genes relevant under the investigated condition.

  15. LOGICAL CONDITIONS ANALYSIS METHOD FOR DIAGNOSTIC TEST RESULTS DECODING APPLIED TO COMPETENCE ELEMENTS PROFICIENCY

    Directory of Open Access Journals (Sweden)

    V. I. Freyman

    2015-11-01

    Full Text Available Subject of Research.Representation features of education results for competence-based educational programs are analyzed. Solution importance of decoding and proficiency estimation for elements and components of discipline parts of competences is shown. The purpose and objectives of research are formulated. Methods. The paper deals with methods of mathematical logic, Boolean algebra, and parametrical analysis of complex diagnostic test results, that controls proficiency of some discipline competence elements. Results. The method of logical conditions analysis is created. It will give the possibility to formulate logical conditions for proficiency determination of each discipline competence element, controlled by complex diagnostic test. Normalized test result is divided into noncrossing zones; a logical condition about controlled elements proficiency is formulated for each of them. Summarized characteristics for test result zones are imposed. An example of logical conditions forming for diagnostic test with preset features is provided. Practical Relevance. The proposed method of logical conditions analysis is applied in the decoding algorithm of proficiency test diagnosis for discipline competence elements. It will give the possibility to automate the search procedure for elements with insufficient proficiency, and is also usable for estimation of education results of a discipline or a component of competence-based educational program.

  16. Improving FoRe: A New Inlet Design for Filtering Samples through Individual Microarray Spots.

    Science.gov (United States)

    de Lange, Victoria; Habegger, Marco; Schmidt, Marco; Vörös, János

    2017-03-24

    In this publication we present an improvement to our previously introduced vertical flow microarray, the FoRe array, which capitalizes on the fusion of immunofiltration and densely packed micron test sites. Filtering samples through individual microarray spots allows us to rapidly analyze dilute samples with high-throughput and high signal-to-noise. Unlike other flowthrough microarrays, in the FoRe design samples are injected into micron channels and sequentially exposed to different targets. This arrangement makes it possible to increase the sensitivity of the microarray by simply increasing the sample volume or to rapidly reconcentrate samples after preprocessing steps dilute the analyte. Here we present a new inlet system which allows us to increase the analyzed sample volume without compromising the micron spot size and dense layout. We combined this with a model assay to demonstrate that the device is sensitive to the amount of antigen, and as a result, sample volume directly correlates to sensitivity. We introduced a simple technique for analysis of blood, which previously clogged the nanometer-sized pores, requiring only microliter volumes expected from an infant heel prick. A drop of blood is mixed with buffer to separate the plasma before reconcentrating the sample on the microarray spot. We demonstrated the success of this procedure by spiking TNF-α into blood and achieved a limit of detection of 18 pM. Compared to traditional protein microarrays, the FoRe array is still inexpensive, customizable, and simple to use, and thanks to these improvements has a broad range of applications from small animal studies to environmental monitoring.

  17. FoCa: a modular treatment planning system for proton radiotherapy with research and educational purposes.

    Science.gov (United States)

    Sánchez-Parcerisa, D; Kondrla, M; Shaindlin, A; Carabe, A

    2014-12-07

    FoCa is an in-house modular treatment planning system, developed entirely in MATLAB, which includes forward dose calculation of proton radiotherapy plans in both active and passive modalities as well as a generic optimization suite for inverse treatment planning. The software has a dual education and research purpose. From the educational point of view, it can be an invaluable teaching tool for educating medical physicists, showing the insights of a treatment planning system from a well-known and widely accessible software platform. From the research point of view, its current and potential uses range from the fast calculation of any physical, radiobiological or clinical quantity in a patient CT geometry, to the development of new treatment modalities not yet available in commercial treatment planning systems. The physical models in FoCa were compared with the commissioning data from our institution and show an excellent agreement in depth dose distributions and longitudinal and transversal fluence profiles for both passive scattering and active scanning modalities. 3D dose distributions in phantom and patient geometries were compared with a commercial treatment planning system, yielding a gamma-index pass rate of above 94% (using FoCa's most accurate algorithm) for all cases considered. Finally, the inverse treatment planning suite was used to produce the first prototype of intensity-modulated, passive-scattered proton therapy, using 13 passive scattering proton fields and multi-leaf modulation to produce a concave dose distribution on a cylindrical solid water phantom without any field-specific compensator.

  18. FoCa: a modular treatment planning system for proton radiotherapy with research and educational purposes

    Science.gov (United States)

    Sánchez-Parcerisa, D.; Kondrla, M.; Shaindlin, A.; Carabe, A.

    2014-12-01

    FoCa is an in-house modular treatment planning system, developed entirely in MATLAB, which includes forward dose calculation of proton radiotherapy plans in both active and passive modalities as well as a generic optimization suite for inverse treatment planning. The software has a dual education and research purpose. From the educational point of view, it can be an invaluable teaching tool for educating medical physicists, showing the insights of a treatment planning system from a well-known and widely accessible software platform. From the research point of view, its current and potential uses range from the fast calculation of any physical, radiobiological or clinical quantity in a patient CT geometry, to the development of new treatment modalities not yet available in commercial treatment planning systems. The physical models in FoCa were compared with the commissioning data from our institution and show an excellent agreement in depth dose distributions and longitudinal and transversal fluence profiles for both passive scattering and active scanning modalities. 3D dose distributions in phantom and patient geometries were compared with a commercial treatment planning system, yielding a gamma-index pass rate of above 94% (using FoCa’s most accurate algorithm) for all cases considered. Finally, the inverse treatment planning suite was used to produce the first prototype of intensity-modulated, passive-scattered proton therapy, using 13 passive scattering proton fields and multi-leaf modulation to produce a concave dose distribution on a cylindrical solid water phantom without any field-specific compensator.

  19. Comparing methods suitable for monitoring marine mammals in low visibility conditions during seismic surveys.

    Science.gov (United States)

    Verfuss, Ursula K; Gillespie, Douglas; Gordon, Jonathan; Marques, Tiago A; Miller, Brianne; Plunkett, Rachael; Theriault, James A; Tollit, Dominic J; Zitterbart, Daniel P; Hubert, Philippe; Thomas, Len

    2018-01-01

    Loud sound emitted during offshore industrial activities can impact marine mammals. Regulations typically prescribe marine mammal monitoring before and/or during these activities to implement mitigation measures that minimise potential acoustic impacts. Using seismic surveys under low visibility conditions as a case study, we review which monitoring methods are suitable and compare their relative strengths and weaknesses. Passive acoustic monitoring has been implemented as either a complementary or alternative method to visual monitoring in low visibility conditions. Other methods such as RADAR, active sonar and thermal infrared have also been tested, but are rarely recommended by regulatory bodies. The efficiency of the monitoring method(s) will depend on the animal behaviour and environmental conditions, however, using a combination of complementary systems generally improves the overall detection performance. We recommend that the performance of monitoring systems, over a range of conditions, is explored in a modelling framework for a variety of species. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Regional impact assessment of land use scenarios in developing countries using the FoPIA approach: findings from five case studies.

    Science.gov (United States)

    König, Hannes Jochen; Uthes, Sandra; Schuler, Johannes; Zhen, Lin; Purushothaman, Seema; Suarma, Utia; Sghaier, Mongi; Makokha, Stella; Helming, Katharina; Sieber, Stefan; Chen, Le; Brouwer, Floor; Morris, Jake; Wiggering, Hubert

    2013-09-01

    The impact of land use changes on sustainable development is of increasing interest in many regions of the world. This study aimed to test the transferability of the Framework for Participatory Impact Assessment (FoPIA), which was originally developed in the European context, to developing countries, in which lack of data often prevents the use of data-driven impact assessment methods. The core aspect of FoPIA is the stakeholder-based assessment of alternative land use scenarios. Scenario impacts on regional sustainability are assessed by using a set of nine regional land use functions (LUFs), which equally cover the economic, social and environmental dimensions of sustainability. The cases analysed in this study include (1) the alternative spatial planning policies around the Merapi volcano and surrounding areas of Yogyakarta City, Indonesia; (2) the large-scale afforestation of agricultural areas to reduce soil erosion in Guyuan, China; (3) the expansion of soil and water conservation measures in the Oum Zessar watershed, Tunisia; (4) the agricultural intensification and the potential for organic agriculture in Bijapur, India; and (5) the land degradation and land conflicts resulting from land division and privatisation in Narok, Kenya. All five regions are characterised by population growth, partially combined with considerable economic development, environmental degradation problems and social conflicts. Implications of the regional scenario impacts as well as methodological aspects are discussed. Overall, FoPIA proved to be a useful tool for diagnosing regional human-environment interactions and for supporting the communication and social learning process among different stakeholder groups. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Blast-induced damage:a summary of SveBeFo investigations

    OpenAIRE

    Saiang, David

    2008-01-01

    This report presents a summary of the blast damage investigation carried out by SveBeFo (Swedish Rock Engineering Research) during the period 1991 to 2003 at various hard rock sites in Sweden. The objective of this report is to present a synopsis of the important factors that influence the development and extent of the blast-induced damage zone, nature and characteristics of blast-induced fractures, and a summary of the blast-damage thickness with reference to the existing perimeter blasting ...

  2. FirefOx Design Reference fO2 Sensor for Hot, Deep Atmospheres

    Science.gov (United States)

    Izenberg, N.; Papadakis, S.; Deglau, D.; Francomacaro, A. S.

    2016-12-01

    Understanding the composition of the lowest portion of Venus' atmosphere is critical to knowing the stable mineralogy of the rocks there. Oxygen gas is a critical trace component, with fugacity, or partial pressure, estimated in the range of 10-19 to 10-22 from early probe measurements down to 22km altitude (Pioneer Venus, Venera), chemical equilibrium measurements, and other modeling. "FirefOx" is a simple oxygen fugacity sensor with the express purpose of determining the partial pressure of oxygen in the lowest scale heights of the Venus atmosphere, and especially the lowest hundreds of meters; the surface atmosphere interface, where the atmosphere and surface move to thermodynamic equilibrium. Knowledge of the fO2 at the surface atmosphere interface is crucial to determining the stable mineralogy of surface materials (e.g. magnetite vs. hematite) and gas chemistry in the near-surface atmosphere FirefOx is a Metal/Metal Oxide oxygen fugacity sensor intended to be mounted on the outside of a Venus descent probe, with electronics housed inside a thermally controlled environment. The sole sensor capability is the precise, accurate detection of the partial pressure of oxygen gas (fO2) in the near-surface environment of Venus, at up to 95-bar pressure (predominantly CO2. Surface temperatures at mean planetary elevation are near 735 K, thus a required operational temperature range of 710-740 K covers a range of near-surface elevations. FirefOx system requirements are low ( 100-200 grams, mass, milliwatt power, several kilobytes total science data). A design reference sensor, composed of custom, Yittria-ZrO ceramic electrolyte, with an encapsulated Pd/PdO standard and patterned Pt electrodes has demonstrated scientifically useful signal-to-noise millivolt level potential at temperatures as low as 620 K, relatable to fO2 by a Nernst equation E = RT/4F ln(PO2/PrefO2) where E = open circuit potential across the sensor electrolyte, R = universal gas constant, T

  3. Integrating free-space optical communication links with existing WiFi (WiFO) network

    Science.gov (United States)

    Liverman, S.; Wang, Q.; Chu, Y.; Duong, T.; Nguyen-Huu, D.; Wang, S.; Nguyen, T.; Wang, A. X.

    2016-02-01

    Recently, free-space optical (FSO) systems have generated great interest due to their large bandwidth potential and a line-of-sight physical layer of protection. In this paper, we propose WiFO, a novel hybrid system, FSO downlink and WiFi uplink, which will integrate currently available WiFi infrastructure with inexpensive infrared light emitting diodes. This system takes full advantage of the mobility inherent in WiFi networks while increasing the downlink bandwidth available to each end user. We report the results of our preliminary investigation that show the capabilities of our prototype design in terms of bandwidth, bit error rates, delays and transmission distances.

  4. Spectroscopy of FO Aquarii - Evidence for reprocessing in a hot wind

    International Nuclear Information System (INIS)

    Martell, P.J.; Kaitchuck, R.H.

    1991-01-01

    Results are presented on spectroscopic observations of FO Aqr, carried out on the nights of September 4-7, 1986 with the 1.8-m Perkins Telescope at Lowell Observatory. It is shown that the observed 21-min modulation of the He II 4686-A line is driven by two emission components which vary in flux and have large negative radial velocities. Arguments are presented to the effect that the modulated portion of the He II 4686-A emission originates from the reprocessing of X-rays in hot winds at these two sites. It is suggested that all other 21-min modulations are due to reprocessing. 32 refs

  5. New method for solving the bending problem of rectangular plates with mixed boundary conditions

    Directory of Open Access Journals (Sweden)

    Liu Xin Min

    2016-01-01

    Full Text Available A new method is used to solve the rectangular plate bending problem with mixed boundary conditions. The method overcomes the complicated derivation of the classical solution by Fourth-order differential problem into integrating question. Under uniform loading rectangular plate bending problem with one side fixed the opposite side half simply supported half fixed the other two sides free rectangular plate, one side simply supported the opposite side half simply supported half fixed the other two sides free rectangular plate is systematically solved. According to the actual boundary conditions of the rectangular plate, the corresponding characteristic equation can easily be set up. It is presented deflection curve equation and the numerical calculation. By compared the results of the equation to the finite element program, we are able to demonstrate the correctness of the method. So the method not only has certain theoretical value, but also can be directly applied to engineering practice.

  6. Preconditioned characteristic boundary conditions based on artificial compressibility method for solution of incompressible flows

    Science.gov (United States)

    Hejranfar, Kazem; Parseh, Kaveh

    2017-09-01

    The preconditioned characteristic boundary conditions based on the artificial compressibility (AC) method are implemented at artificial boundaries for the solution of two- and three-dimensional incompressible viscous flows in the generalized curvilinear coordinates. The compatibility equations and the corresponding characteristic variables (or the Riemann invariants) are mathematically derived and then applied as suitable boundary conditions in a high-order accurate incompressible flow solver. The spatial discretization of the resulting system of equations is carried out by the fourth-order compact finite-difference (FD) scheme. In the preconditioning applied here, the value of AC parameter in the flow field and also at the far-field boundary is automatically calculated based on the local flow conditions to enhance the robustness and performance of the solution algorithm. The code is fully parallelized using the Concurrency Runtime standard and Parallel Patterns Library (PPL) and its performance on a multi-core CPU is analyzed. The incompressible viscous flows around a 2-D circular cylinder, a 2-D NACA0012 airfoil and also a 3-D wavy cylinder are simulated and the accuracy and performance of the preconditioned characteristic boundary conditions applied at the far-field boundaries are evaluated in comparison to the simplified boundary conditions and the non-preconditioned characteristic boundary conditions. It is indicated that the preconditioned characteristic boundary conditions considerably improve the convergence rate of the solution of incompressible flows compared to the other boundary conditions and the computational costs are significantly decreased.

  7. Quantitative evaluation methods of skin condition based on texture feature parameters

    Directory of Open Access Journals (Sweden)

    Hui Pang

    2017-03-01

    Full Text Available In order to quantitatively evaluate the improvement of the skin condition after using skin care products and beauty, a quantitative evaluation method for skin surface state and texture is presented, which is convenient, fast and non-destructive. Human skin images were collected by image sensors. Firstly, the median filter of the 3 × 3 window is used and then the location of the hairy pixels on the skin is accurately detected according to the gray mean value and color information. The bilinear interpolation is used to modify the gray value of the hairy pixels in order to eliminate the negative effect of noise and tiny hairs on the texture. After the above pretreatment, the gray level co-occurrence matrix (GLCM is calculated. On the basis of this, the four characteristic parameters, including the second moment, contrast, entropy and correlation, and their mean value are calculated at 45 ° intervals. The quantitative evaluation model of skin texture based on GLCM is established, which can calculate the comprehensive parameters of skin condition. Experiments show that using this method evaluates the skin condition, both based on biochemical indicators of skin evaluation methods in line, but also fully consistent with the human visual experience. This method overcomes the shortcomings of the biochemical evaluation method of skin damage and long waiting time, also the subjectivity and fuzziness of the visual evaluation, which achieves the non-destructive, rapid and quantitative evaluation of skin condition. It can be used for health assessment or classification of the skin condition, also can quantitatively evaluate the subtle improvement of skin condition after using skin care products or stage beauty.

  8. A Scalable Method for Regioselective 3-Acylation of 2-Substituted Indoles under Basic Conditions

    DEFF Research Database (Denmark)

    Johansson, Karl Henrik; Urruticoechea, Andoni; Larsen, Inna

    2015-01-01

    Privileged structures such as 2-arylindoles are recurrent molecular scaffolds in bioactive molecules. We here present an operationally simple, high yielding and scalable method for regioselective 3-acylation of 2-substituted indoles under basic conditions using functionalized acid chlorides. The ....... The method shows good tolerance to both electron-withdrawing and donating substituents on the indole scaffold and gives ready access to a variety of functionalized 3-acylindole building blocks suited for further derivatization....

  9. Haulage Methods in Different Areas of Nepal and the Health Condition of the Porters in Kathmandu

    OpenAIRE

    Kaneda, Eiko; Yamauchi, Masaki; Ohwatari, Nobu; Lee, Jeong-Beom; Kosaka, Mitsuo

    1999-01-01

    The complicated geographical features of Nepal make transport of goods difficult. People have to depend on human power even today, especially porters who use a number of different transport styles. The objectives of this study were to document (1) the characteristics of haulage methods in relation to the geographical conditions, and (2) the diurnal activities and health of porters in Kathmandu. The observed methods used by the porters in Nepal to carry loads were divided into four main classe...

  10. A new machine condition monitoring method based on likelihood change of a stochastic model

    Science.gov (United States)

    Hwang, Kyu Hwan; Lee, Jong Min; Hwang, Yoha

    2013-12-01

    In industry, a machine condition monitoring system has become more important with ever-increasing requirements on productivity and cost saving. Although researches have been very active, many currently available intelligent monitoring methods have common drawbacks, which are the requirement of defect model for every interested defect type and inaccurate diagnostic performance. To overcome those drawbacks, authors propose a new machine condition monitoring method based on likelihood change of a stochastic model using only normal operation data. Hidden Markov model (HMM) has been selected as a stochastic model based on its accurate and robust diagnostic performance. By observing the likelihood change of a pre-trained normal HMM on incoming data in unknown condition, defect can be precisely detected from sudden drop of likelihood value. Therefore, though the types of defect cannot be identified, defects can be precisely detected with only normal model. Defect models can also be used when defect data are available. And in this case, not only the precise detection of defect but also the correct identification of defect type is possible. In this paper, the proposed monitoring method based on likelihood change of normal continuous HMM have been successfully applied to monitoring of the machine condition and weld condition, proving its great potential with accurate and robust diagnostic performance results.

  11. Element stacking method for topology optimization with material-dependent boundary and loading conditions

    DEFF Research Database (Denmark)

    Yoon, Gil Ho; Park, Y.K.; Kim, Y.Y.

    2007-01-01

    A new topology optimization scheme, called the element stacking method, is developed to better handle design optimization involving material-dependent boundary conditions and selection of elements of different types. If these problems are solved by existing standard approaches, complicated finite...

  12. Formative Research on the Simplifying Conditions Method (SCM) for Task Analysis and Sequencing.

    Science.gov (United States)

    Kim, YoungHwan; Reigluth, Charles M.

    The Simplifying Conditions Method (SCM) is a set of guidelines for task analysis and sequencing of instructional content under the Elaboration Theory (ET). This article introduces the fundamentals of SCM and presents the findings from a formative research study on SCM. It was conducted in two distinct phases: design and instruction. In the first…

  13. Effects of Missing Data Methods in SEM under Conditions of Incomplete and Nonnormal Data

    Science.gov (United States)

    Li, Jian; Lomax, Richard G.

    2017-01-01

    Using Monte Carlo simulations, this research examined the performance of four missing data methods in SEM under different multivariate distributional conditions. The effects of four independent variables (sample size, missing proportion, distribution shape, and factor loading magnitude) were investigated on six outcome variables: convergence rate,…

  14. The initial conditions of observed star clusters - I. Method description and validation

    NARCIS (Netherlands)

    Pijloo, J.T.; Portegies Zwart, S.F.; Alexander, P.E.R.; Gieles, M.; Larsen, S.S.; Groot, P.J.; Devecchi, B.A.

    2015-01-01

    We have coupled a fast, parametrized star cluster evolution code to a Markov Chain Monte Carlo code to determine the distribution of probable initial conditions of observed star clusters, that may serve as a starting point for future N-body calculations. In this paper, we validate our method by

  15. Adhesion of resin composites to biomaterials in dentistry : an evaluation of surface conditioning methods

    NARCIS (Netherlands)

    Özcan, Mutlu

    2003-01-01

    Since previous investigations revealed that most clinical failures in adhesively luted ceramic restorations initiate from the cementation or internal surfaces, the study presented in Chapter II evaluated the effect of three different surface conditioning methods on the bond strength of a Bis-GMA

  16. Condition Monitoring Using Computational Intelligence Methods Applications in Mechanical and Electrical Systems

    CERN Document Server

    Marwala, Tshilidzi

    2012-01-01

    Condition monitoring uses the observed operating characteristics of a machine or structure to diagnose trends in the signal being monitored and to predict the need for maintenance before a breakdown occurs. This reduces the risk, inherent in a fixed maintenance schedule, of performing maintenance needlessly early or of having a machine fail before maintenance is due either of which can be expensive with the latter also posing a risk of serious accident especially in systems like aeroengines in which a catastrophic failure would put lives at risk. The technique also measures responses from the whole of the system under observation so it can detect the effects of faults which might be hidden deep within a system, hidden from traditional methods of inspection. Condition Monitoring Using Computational Intelligence Methods promotes the various approaches gathered under the umbrella of computational intelligence to show how condition monitoring can be used to avoid equipment failures and lengthen its useful life, m...

  17. Method for signal conditioning and data acquisition system, based on variable amplification and feedback technique

    International Nuclear Information System (INIS)

    Conti, Livio; Sgrigna, Vittorio; Zilpimiani, David; Assante, Dario

    2014-01-01

    An original method of signal conditioning and adaptive amplification is proposed for data acquisition systems of analog signals, conceived to obtain a high resolution spectrum of any input signal. The procedure is based on a feedback scheme of the signal amplification with aim at maximizing the dynamic range and resolution of the data acquisition system. The paper describes the signal conditioning, digitization, and data processing procedures applied to an a priori unknown signal in order to enucleate its amplitude and frequency content for applications in different environments: on the ground, in space, or in the laboratory. An electronic board of the conditioning module has also been constructed and described. In the paper are also discussed the main fields of application and advantages of the method with respect to those known today

  18. Exergy analysis of heating, refrigerating and air conditioning methods and applications

    CERN Document Server

    Dincer, Ibrahim

    2015-01-01

    Improve and optimize efficiency of HVAC and related energy systems from an exergy perspective. From fundamentals to advanced applications, Exergy Analysis of Heating, Air Conditioning, and Refrigeration provides readers with a clear and concise description of exergy analysis and its many uses. Focusing on the application of exergy methods to the primary technologies for heating, refrigerating, and air conditioning, Ibrahim Dincer and Marc A. Rosen demonstrate exactly how exergy can help improve and optimize efficiency, environmental performance, and cost-effectiveness. The book also discusses the analysis tools available, and includes many comprehensive case studies on current and emerging systems and technologies for real-world examples. From introducing exergy and thermodynamic fundamentals to presenting the use of exergy methods for heating, refrigeration, and air conditioning systems, this book equips any researcher or practicing engineer with the tools needed to learn and master the application of exergy...

  19. [Research on the identification method of LTE condition in the laser-induced plasma].

    Science.gov (United States)

    Fan, Juan-juan; Huang, Dan; Wang, Xin; Zhang, Lei; Ma, Wei-guang; Dong, Lei; Yin, Wang-bao; Jia, Suo-tang

    2014-12-01

    Because of the poor accuracy of the commonly used Boltzmann plot method and double-line method, the Boltzmann-Maxwell distribution combined with the Saha-Eggert formula is proposed to improve the measurement accuracy of the plasma temperature; the simple algorithm for determining the linewidth of the emission line was established according to the relationship between the area and the peak value of the Gaussian formula, and the plasma electron density was calculated through the Stark broadening of the spectral lines; the method for identifying the plasma local thermal equilibrium (LTE) condition was established based on the McWhirter criterion. The experimental results show that with the increase in laser energy, the plasma temperature and electron density increase linearly; when the laser energy changes within 127~510 mJ, the plasma electron density changes in the range of 1.30532X10(17)~1.87322X10(17) cm(-3), the plasma temperature changes in the range of 12586~12957 K, and all the plasma generated in this experiment meets the LTE condition threshold according to the McWhirter criterion. For element Al, there exist relatively few observable lines at the same ionization state in the spectral region of the spectrometer, thus it is unable to use the Boltzmann plane method to calculate temperature. One hundred sets of Al plasma spectra were used for temperature measurement by employing the Saha-Boltzmann method and the relative standard deviation (RSD) value is 0.4%, and compared with 1.3% of the double line method, the accuracy has been substantially increased. The methods proposed can be used for rapid plasma temperature and electron density calculation, the LTE condition identification, and are valuable in studies such as free calibration, spectral effectiveness analysis, spectral temperature correction, the best collection location determination, LTE condition distribution in plasma, and so on.

  20. Application of Response Surface Methods To Determine Conditions for Optimal Genomic Prediction

    Science.gov (United States)

    Howard, Réka; Carriquiry, Alicia L.; Beavis, William D.

    2017-01-01

    An epistatic genetic architecture can have a significant impact on prediction accuracies of genomic prediction (GP) methods. Machine learning methods predict traits comprised of epistatic genetic architectures more accurately than statistical methods based on additive mixed linear models. The differences between these types of GP methods suggest a diagnostic for revealing genetic architectures underlying traits of interest. In addition to genetic architecture, the performance of GP methods may be influenced by the sample size of the training population, the number of QTL, and the proportion of phenotypic variability due to genotypic variability (heritability). Possible values for these factors and the number of combinations of the factor levels that influence the performance of GP methods can be large. Thus, efficient methods for identifying combinations of factor levels that produce most accurate GPs is needed. Herein, we employ response surface methods (RSMs) to find the experimental conditions that produce the most accurate GPs. We illustrate RSM with an example of simulated doubled haploid populations and identify the combination of factors that maximize the difference between prediction accuracies of best linear unbiased prediction (BLUP) and support vector machine (SVM) GP methods. The greatest impact on the response is due to the genetic architecture of the population, heritability of the trait, and the sample size. When epistasis is responsible for all of the genotypic variance and heritability is equal to one and the sample size of the training population is large, the advantage of using the SVM method vs. the BLUP method is greatest. However, except for values close to the maximum, most of the response surface shows little difference between the methods. We also determined that the conditions resulting in the greatest prediction accuracy for BLUP occurred when genetic architecture consists solely of additive effects, and heritability is equal to one. PMID

  1. A New Experimental Method for in Situ Corrosion Monitoring Under Alternate Wet-Dry Conditions

    Directory of Open Access Journals (Sweden)

    Wei Ke

    2009-12-01

    Full Text Available A new experimental method was applied in in situ corrosion monitoring of mild steel Q235 under alternate wet-dry conditions. The thickness of the electrolyte film during the wet cycle was monitored by a high-precision balance with a sensibility of 0.1 mg. At the same time, an electrochemical impedance technique was employed to study the effect of film thickness on corrosion rates. Experimental results showed that there was a critical electrolyte film condition for which the corrosion rate reached a maximum during wet-dry cycles. For the substrate, the critical condition could be described by a film thickness of about 17 μm. For the rusted specimen, the critical condition could be described by an electrolyte amount of about 0.038 g, which is equivalent to a film thickness of 38 μm. This monitoring system was very useful for studying atmospheric corrosion of metals covered by corrosion products.

  2. Absorption and impedance boundary conditions for phased geometrical-acoustics methods

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2012-01-01

    Defining accurate acoustical boundary conditions is of crucial importance for room acoustic simulations. In predicting sound fields using phased geometrical acoustics methods, both absorption coefficients and surface impedances of the boundary surfaces can be used, but no guideline has been...... developed on which boundary condition produces accurate results. In this study, various boundary conditions in terms of normal, random, and field incidence absorption coefficients and normal incidence surface impedance are used in a phased beam tracing model, and the simulated results are validated...... with boundary element solutions. Two rectangular rooms with uniform and non-uniform absorption distributions are tested. Effects of the neglect of reflection phase shift are also investigated. It is concluded that the impedance, random incidence, and field incidence absorption boundary conditions produce...

  3. Assessing the Impact of Land Use Policy on Urban-Rural Sustainability Using the FoPIA Approach in Yogyakarta, Indonesia

    Directory of Open Access Journals (Sweden)

    Junun Sartohadi

    2010-07-01

    Full Text Available This paper presents the results of a sustainability impact assessment (SIA of policy induced land use changes in Yogyakarta, Indonesia. The regional problems include rapid expansions of urban areas, due to high population pressure, and the conversion of paddy fields and forests into settlements. The objective of this study was to assess the impacts of two land use policies on social, economic, and environmental Land Use Functions (LUFs in Yogyakarta. The following scenarios were developed for the SIA: a forest protection scenario (S1, a paddy field conservation scenario (S2, and a counterfactual (no policy scenario of ‘Business As Usual’ (BAU. The Framework for Participatory Impact Assessment (FoPIA was applied to conduct an expert-based impact assessment. For the specification of the regional sustainability context, a set of nine key LUFs and associated indicators were developed, including three social, three economic, and three environmental sustainability criteria. The resulting scenario impacts of the assessment differed considerably, with positive impacts of the S1 and S2 scenarios on seven of nine LUFs, and negative impacts of the BAU scenario on six LUFs. The perception of the FoPIA method by the regional stakeholders was positive. We conclude that this method contributes toward an enhanced regional understanding of policy effects and sustainability, particularly in data-poor environments.

  4. Equatorial Ionization Anomaly representation by TEC and foF2: A comparison between observational data and SUPIM simulation over Brazil

    Science.gov (United States)

    Nogueira, Paulo; Abdu, Mangalathayil Ali; Batista, Inez S.; Souza, Jonas

    The equatorial ionization anomaly (EIA) is studied using the Total Electron Content (TEC) of the ionosphere, measured by monitoring the Global Positioning System (GPS) satellites and F2 layer critical frequency (foF2), measured by digital ionosondes in the Brazilian region. In order to evaluate the strength and development of the equatorial anomaly, the following two parameters are used: ∆f oF 2 and ∆V T EC that represent the difference of foF2 and TEC, respectively, between the equatorial (EIA trough) and low latitude (EIA crest) sites. Significant differences in the EIA strength as represented by the two parameters and in its variations were observed, which motivated us to investigate these differences using model simulations. We have used the Sheffield University Plasmasphere Ionosphere Model (SUPIM) in this study, and the ionospheric data was obtained from digital ionosondes operated at São Lué (-2° 35', -44° 12'), a ıs ° ° ° ° Fortaleza (-3 52', -38 25') and Cachoeira Paulista (-22 41', -44 59') and from GPS receivers operated at São Lué and São José dos Campos (-23,18; 314,12), in Brazil. The comparisons a ıs a are performed for different solar flux conditions.

  5. Compact large FoV gamma camera for breast molecular imaging

    Science.gov (United States)

    Pani, R.; Cinti, M. N.; Pellegrini, R.; Betti, M.; Devincentis, G.; Bennati, P.; Ridolfi, S.; Iurlaro, G.; Montani, L.; Scafè, R.; Marini, M.; Porfiri, L. M.; Giachetti, G.; Baglini, F.; Salvadori, G.; Madesani, M.; Pieracci, M.; Catarsi, F.; Bigongiari, A.

    2006-12-01

    The very low sensitivity of scintimammography for tumours under 1 cm in diameter, with current nuclear medicine cameras, is the major limitation in recommending this test modality for screening purposes. To improve this diagnostic technique,a new concept of scintillation gamma camera, which fits the best requirements for functional breast imaging has been developed under "Integrated Mammographic Imaging" (IMI) project. This camera consists of a large detection head (6″×7″),very compact sized and with light weight to be easily positioned in the same X-ray geometry. The detection head consists of matrix of 42 photodetector Hamamatsu 1 in 2 square H8520-C12 PSPMTs, which are closely packed and coupled to a NaI(Tl) scintillating array, with individual crystal pixel 2×2×6 mm 3 size. Large FoV camera shows a very good pixel identification in the detection dead zones between tubes allowing an accurate LUT correction of the final image reconstruction. Electronic read-out was especially designed to optimize the intrinsic spatial resolution and camera compactness. With respect to Anger camera, the overall spatial resolution is improved up to 40% while the overall energy resolution values is ˜16% at 140 keV. Large FoV dedicated camera was characterized and tested by phantom studies; and clinical trials are currently performed. For all patients, compression views have been acquiring for both breasts in craniocaudal projections, and are compared with standard gamma camera images.

  6. Application of uncertainty analysis method for calculations of accident conditions for RP AES-2006

    International Nuclear Information System (INIS)

    Zajtsev, S.I.; Bykov, M.A.; Zakutaev, M.O.; Siryapin, V.N.; Petkevich, I.G.; Siryapin, N.V.; Borisov, S.L.; Kozlachkov, A.N.

    2015-01-01

    An analysis of some accidents using the uncertainly assessment methods is given. The list of the variable parameters incorporated the model parameters of the computer codes, initial and boundary conditions of reactor plant, neutronics. On the basis of the performed calculations of the accident conditions using the statistical method, errors assessment is presented in the determination of the main parameters comparable with the acceptance criteria. It was shown that in the investigated accidents the values of the calculated parameters with account for their error obtained from TRAP-KS and KORSAR/GP Codes do not exceed the established acceptance criteria. Besides, these values do not exceed the values obtained in the conservative calculations. A possibility in principle of the actual application of the method of estimation of uncertainty was shown to justify the safety of WWER AES-2006 using the thermal-physical codes KORSAR/GP and TRAP-KS, PANDA and SUSA programs [ru

  7. Accurate and Autonomous Star Acquisition Method for Star Sensor under Complex Conditions

    Directory of Open Access Journals (Sweden)

    Hao Zhang

    2017-01-01

    Full Text Available Star sensor is a preferred attitude measurement device for its extremely high accuracy. Star acquisition is the essential and critical procedure, which is aiming at acquiring accurate star areas. However, degenerated acquisition results under complex conditions become one of the major restrictions for modern star sensor. In this paper, an accurate and autonomous star acquisition method is proposed. Mathematical morphology and variable thresholding are combined for accurate star extraction; motion PSF is estimated in frequency domain and nonlinear filter is adopted for star restoration. Accurate star acquisition can be achieved based on only one star image. Simulations and laboratory experiments are conducted for verification. Several existing methods are also reproduced for comparison. Acquisition results demonstrate that the proposed method is effective and an excellent performance can be achieved autonomously under complex conditions, along with more detected stars and improved acquisition accuracy.

  8. Pressure-volume-temperature gauging method experiment using liquid nitrogen under microgravity condition of parabolic flight

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Man Su; Park, Hana; Yoo, Don Gyu; Jeong, Sang Kwon [Cryogenic Engineering Laboratory, Department of Mechanical Engineering, KAIST, Daejeon (Korea, Republic of); Jung, Young Suk [Launcher Systems Development Team, Korea Aerospace Research Institute, Daejeon (Korea, Republic of)

    2014-06-15

    Measuring an exact amount of remaining cryogenic liquid propellant under microgravity condition is one of the important issues of rocket vehicle. A Pressure-Volume-Temperature (PVT) gauging method is attractive due to its minimal additional hardware and simple gauging process. In this paper, PVT gauging method using liquid nitrogen is investigated under microgravity condition with parabolic flight. A 9.2 litre metal cryogenic liquid storage tank containing approximately 30% of liquid nitrogen is pressurized by ambient temperature helium gas. During microgravity condition, the inside of the liquid tank becomes near-isothermal condition within 1 K difference indicated by 6 silicon diode sensors vertically distributed in the middle of the liquid tank. Helium injection with higher mass flow rate after 10 seconds of the waiting time results in successful measurements of helium partial pressure in the tank. Average liquid volume measurement error is within 11% of the whole liquid tank volume and standard deviation of errors is 11.9. As a result, the applicability of PVT gauging method to liquid.

  9. Conversion of primordial germ cells to pluripotent stem cells: methods for cell tracking and culture conditions.

    Science.gov (United States)

    Nagamatsu, Go; Suda, Toshio

    2013-01-01

    Primordial germ cells (PGCs) are unipotent cells committed to germ lineage: PGCs can only differentiate into gametes in vivo. However, upon fertilization, germ cells acquire the capacity to differentiate into all cell types in the body, including germ cells. Therefore, germ cells are thought to have the potential for pluripotency. PGCs can convert to pluripotent stem cells in vitro when cultured under specific conditions that include bFGF, LIF, and the membrane-bound form of SCF (mSCF). Here, the culture conditions which efficiently convert PGCs to pluripotent embryonic germ (EG) cells are described, as well as methods used for identifying pluripotent candidate cells during culture.

  10. Novel cellulose ester substrates for high performance flat-sheet thin-film composite (TFC) forward osmosis (FO) membranes

    KAUST Repository

    Ong, Rui Chin

    2015-01-01

    A novel hydrophilic cellulose ester with a high intrinsic water permeability and a water partition coefficient was discovered to construct membrane supports for flat-sheet thin film composite (TFC) forward osmosis (FO) membranes for water reuse and seawater desalination with high performance. The performance of TFC-FO membranes prepared from the hydrophilic cellulose ester containing a high degree of OH and a moderate degree of Pr substitutions clearly surpasses those prepared from cellulose esters and other polymers with moderate hydrophilicity. Post-treatments of TFC-FO membranes using sodium dodecyl sulfate (SDS) and glycerol followed by heat treatment further enhance the water flux without compromising the selectivity. Positron annihilation lifetime analyses have confirmed that the SDS/glycerol post-treatment increases the free volume size and fractional free volume of the polyamide selective layer. The newly developed post-treated TFC-FO membranes exhibit a remarkably high water flux up to 90 LMH when the selective layer is oriented towards the draw solution (i.e., PRO mode) using 1. M NaCl as the draw solution and DI water as the feed. For seawater desalination, the membranes display a high water flux up to 35 LMH using a 2. M NaCl draw solution. These water fluxes exceeded the water fluxes achieved by other types of FO membranes reported in literatures. © 2014 Elsevier B.V.

  11. Optimal Fixation Conditions and DNA Extraction Methods for MLPA Analysis on FFPE Tissue-Derived DNA.

    Science.gov (United States)

    Atanesyan, Lilit; Steenkamer, Maryvonne J; Horstman, Anja; Moelans, Cathy B; Schouten, Jan P; Savola, Suvi P

    2017-01-01

    Molecular genetic analysis of formalin-fixed, paraffin-embedded (FFPE) tissues is of great importance both for research and diagnostics. Multiplex ligation-dependent probe amplification (MLPA) is a widely used technique for gene copy number determination, and it has been successfully used for FFPE tissue-extracted DNA analysis. However, there have been no studies addressing the effect of tissue fixation procedures and DNA extraction methods on MLPA. This study therefore focuses on selecting optimal preanalytic conditions such as FFPE tissue preparation conditions and DNA extraction methods. Healthy tissues were fixed in buffered or nonbuffered formalin for 1 hour, 12 to 24 hours, or 48 to 60 hours at 4 °C or at room temperature. DNA extracted from differently fixed and subsequently paraffin-embedded tissues was used for MLPA. Four commercial DNA extraction kits and one in-house method were compared. Tissues fixed for 12 to 24 hours in buffered formalin at room temperature produced DNA with the most optimal quality for MLPA. The in-house FFPE DNA extraction method was shown to perform as efficient as or even superior to other methods in terms of suitability for MLPA, time and cost-efficiency, and ease of performance. FFPE-extracted DNA is well suitable for MLPA analysis, given that optimal tissue fixation and DNA extraction methods are chosen. © American Society for Clinical Pathology, 2017.

  12. An in-well heat-tracer-test method for evaluating borehole flow conditions

    Science.gov (United States)

    Sellwood, Stephen M.; Hart, David J.; Bahr, Jean M.

    2015-12-01

    An improved method is presented for characterizing vertical borehole flow conditions in open boreholes using in-well heat tracer tests monitored by a distributed temperature sensing (DTS) system. This flow logging method uses an electrical resistance heater to warm slugs of water within bedrock boreholes and DTS monitoring of subsequent heat migration to measure borehole flow characteristics. Use of an electrical resistance heater allows for controlled test initiation, while the DTS allows for detailed monitoring of heat movement within the borehole. The method was evaluated in bedrock boreholes open to Cambrian sandstone formations in south-central Wisconsin (USA). The method was successfully used to measure upward flow, downward flow, and zero flow, and to identify changes in borehole flow rates associated with fracture flow and porous media flow. The main benefits of the DTS-monitored in-well heat tracer test method of borehole flow logging are (1) borehole flow direction and changes in borehole fluid velocity are readily apparent from a simple plot of the field data, (2) the case of zero vertical borehole flow is easily and confidently identified, and (3) the ability to monitor temperatures over the full borehole length simultaneously and in rapid succession provides detailed flow data with minimal disturbance of the borehole flow. The results of this study indicate that DTS-monitored in-well heat tracer tests are an effective method of characterizing borehole flow conditions.

  13. Enhancing sewage sludge dewaterability by bioleaching approach with comparison to other physical and chemical conditioning methods.

    Science.gov (United States)

    Liu, Fenwu; Zhou, Jun; Wang, Dianzhan; Zhou, Lixiang

    2012-01-01

    The sewage sludge conditioning process is critical to improve the sludge dewaterability prior to mechanical dewatering. Traditionally, sludge is conditioned by physical or chemical approaches, mostly with the addition of inorganic or organic chemicals. Here we report that bioleaching, an efficient and economical microbial method for the removal of sludge-borne heavy metals, also plays a significant role in enhancing sludge dewaterability. The effects of bioleaching and physical or chemical approaches on sludge dewaterability were compared. The conditioning result of bioleaching by Acidithiobacillus thiooxidans and Acidithiobacillus ferrooxidans on sludge dewatering was investigated and compared with the effects of hydrothermal (121 degrees C for 2 hr), microwave (1050 W for 50 sec), ultrasonic (250 W for 2 min), and chemical conditioning (24% ferric chloride and 68% calcium oxide; dry basis). The results show that the specific resistance to filtration (SRF) or capillary suction time (CST) of sludge is decreased by 93.1% or 74.1%, respectively, after fresh sludge is conditioned by bioleaching, which is similar to chemical conditioning treatment with ferric chloride and calcium oxide but much more effective than other conditioning approaches including hydrothermal, microwave, and ultrasonic conditioning. Furthermore, after sludge dewatering, bioleached sludge filtrate contains the lowest concentrations of chroma (18 times), COD (542 mg/L), total N (TN, 300 mg/L), NH4(+)-N (208 mg/L), and total P (TP, 2 mg/L) while the hydrothermal process resulted in the highest concentration of chroma (660 times), COD (18,155 mg/L), TN (472 mg/L), NH4(+)-N (381 mg/L), and TP (191 mg/L) among these selected conditioning methods. Moreover, unlike chemical conditioning, sludge bioleaching does not result in a significant reduction of organic matter, TN, and TP in the resulting dewatered sludge cake. Therefore, considering sludge dewaterability and the chemical properties of sludge

  14. Knowledge Brokerage for Impact Assessment of Land Use Scenarios in Inner Mongolia, China: Extending and Testing the FoPIA Approach

    Directory of Open Access Journals (Sweden)

    Hannes J. König

    2015-04-01

    Full Text Available While land serves numerous societal functions and contributes to sustainable development, it is often unclear how these functions are affected by political decisions and common drivers of land use change, such as economic development, climate change and demographic change. This study evaluates alternative land use scenarios in reference to a rural region of Inner Mongolia Autonomous Region (China, where various processes and decisions have historically triggered unsustainable development. The scientifically tested “Framework for Participatory Impact Assessment (FoPIA” method is developed further to address specific features of the case study region, and its function as a knowledge-brokerage (KB tool is evaluated. Three scenarios are developed and analysed in expert workshops. “Land intensification: Agriculture” and “Land intensification: Mining” scenarios are found to have mainly negative environmental and social effects and positive economic impacts, while the “Environmental conservation and tourism” scenario is found to more positively affect all three sustainability dimensions. Assessments of methodological phases show that the FoPIA primarily serves to establish the KB process and that the framework particularly benefits from early examinations of scientific results by policy makers.

  15. Using stationary image based data collection method for evaluation of traffic sign condition

    Directory of Open Access Journals (Sweden)

    Majid Khalilikhah

    2016-12-01

    Full Text Available Transportation asset management helps monitor the transportation systems and optimize the construction, operation, and maintenance of assets. Many state Department of Transportations (DOTs have already established asset management systems for high cost and low quantity assets, e.g., bridge and tunnel assets. However, due to the sheer number of traffic signs deployed by DOTs, statewide sign inventory and condition information are not well developed. Currently, using handheld devices is the most selected method by agencies to measure signs. To address safety challenge and high cost of data collection, an innovative stationary image based method has recently been proposed. This paper discusses the advantages and disadvantages of such image based method over using handheld devices in terms of the accuracy, possibility and consistency of data, speed, safety, maintenance, and cost. At its completion, this study provides suggestions to tackle the issues associated with image based method.

  16. An efficient heuristic method for dynamic portfolio selection problem under transaction costs and uncertain conditions

    Science.gov (United States)

    Najafi, Amir Abbas; Pourahmadi, Zahra

    2016-04-01

    Selecting the optimal combination of assets in a portfolio is one of the most important decisions in investment management. As investment is a long term concept, looking into a portfolio optimization problem just in a single period may cause loss of some opportunities that could be exploited in a long term view. Hence, it is tried to extend the problem from single to multi-period model. We include trading costs and uncertain conditions to this model which made it more realistic and complex. Hence, we propose an efficient heuristic method to tackle this problem. The efficiency of the method is examined and compared with the results of the rolling single-period optimization and the buy and hold method which shows the superiority of the proposed method.

  17. A Grid Voltage Measurement Method for Wind Power Systems during Grid Fault Conditions

    Directory of Open Access Journals (Sweden)

    Cheol-Hee Yoo

    2014-11-01

    Full Text Available Grid codes in many countries require low-voltage ride-through (LVRT capability to maintain power system stability and reliability during grid fault conditions. To meet the LVRT requirement, wind power systems must stay connected to the grid and also supply reactive currents to the grid to support the recovery from fault voltages. This paper presents a new fault detection method and inverter control scheme to improve the LVRT capability for full-scale permanent magnet synchronous generator (PMSG wind power systems. Fast fault detection can help the wind power systems maintain the DC-link voltage in a safe region. The proposed fault detection method is based on on-line adaptive parameter estimation. The performance of the proposed method is verified in comparison to the conventional voltage measurement method defined in the IEC 61400-21 standard.

  18. A system and a method comprising an array of bending elements for determining a condition

    DEFF Research Database (Denmark)

    2014-01-01

    direction, when exposed to a condition, which may be a temperature, a pressure, a pH, a humidity or a presence of a predetermined molecule. The elongated elements may have a first surface and a second surface having different degrees of contraction/extension when exposed to the condition, where the first......A system comprising a sensor element and a sensing system, a method of operating it, a sensor element and a method of providing it, where the sensor element has a substrate from which a plurality of elongate, bendable elements extend. The elongated elements are configured to bend, in the same...... surfaces all point in the same direction. The sensing system may relate on a large number of elongate elements positioned within a given area on the sensor element....

  19. A New Method of Reliability Evaluation Based on Wavelet Information Entropy for Equipment Condition Identification

    International Nuclear Information System (INIS)

    He, Z J; Zhang, X L; Chen, X F

    2012-01-01

    Aiming at reliability evaluation of condition identification of mechanical equipment, it is necessary to analyze condition monitoring information. A new method of reliability evaluation based on wavelet information entropy extracted from vibration signals of mechanical equipment is proposed. The method is quite different from traditional reliability evaluation models that are dependent on probability statistics analysis of large number sample data. The vibration signals of mechanical equipment were analyzed by means of second generation wavelet package (SGWP). We take relative energy in each frequency band of decomposed signal that equals a percentage of the whole signal energy as probability. Normalized information entropy (IE) is obtained based on the relative energy to describe uncertainty of a system instead of probability. The reliability degree is transformed by the normalized wavelet information entropy. A successful application has been achieved to evaluate the assembled quality reliability for a kind of dismountable disk-drum aero-engine. The reliability degree indicates the assembled quality satisfactorily.

  20. A Non-parametric Method for Calculating Conditional Stressed Value at Risk

    Directory of Open Access Journals (Sweden)

    Kohei Marumo

    2017-01-01

    Full Text Available We consider the Value at Risk (VaR of a portfolio under stressed conditions. In practice, the stressed VaR (sVaR is commonly calculated using the data set that includes the stressed period. It tells us how much the risk amount increases if we use the stressed data set. In this paper, we consider the VaR under stress scenarios. Technically, this can be done by deriving the distribution of profit or loss conditioned on the value of risk factors. We use two methods; the one that uses the linear model and the one that uses the Hermite expansion discussed by Marumo and Wolff (2013, 2016. Numerical examples shows that the method using the Hermite expansion is capable of capturing the non-linear effects such as correlation collapse and volatility clustering, which are often observed in the markets.

  1. Methods for conditioning wastes from spent fuel cans and dissolver residues

    International Nuclear Information System (INIS)

    De Regge, P.; Loida, A.; Schmidt-Hansberg, T.; Sombret, C.

    1985-04-01

    Several methods for conditioning spent fuel decladding hulls or dissolver residues have been considered in various countries of the European Community. Five of these methods use embedding technique with or without prior compaction: they are based on incorporation in metallic alloys, glass, ceramics, cements and metals or graphite compounds. A sixth one consists in melting the decladding materials. The corresponding research programs have been pursued to varying states of progress with regard to demonstrating their feasibility on an industrial scale and the use of genuine wastes in bench scale experiments. The properties of the conditioned wastes have been investigated. Special attention has been paid to the corrosion resistance to various aqueous media as tap water, brine or clayey water. Although no categorical conclusion can be drawn from the initial results, the available finding provide a basis for assessing the different processes [fr

  2. Use of laminar chromatographic methods for determination of separation conditions in column extraction chromatography

    International Nuclear Information System (INIS)

    Ghersini, G.; Cerrai, E.

    1978-01-01

    Possibilities of using laminar chromatographic methods (paper and thin-layer chromatography) to determine optimal separation conditions in column extraction chromatography are analysed. Most of the given laminar methods are presented as Rf-spectra, i.e. as dependences of Rf found experimentally on eluating solution component concentration. Interrelation between Rf and distribution coefficients of corresponding liquid extraction systems and retention volumes of chromatographic columns is considered. Literature data on extraction paper and thin-layer chromatography of elements with various immovable phases are presented

  3. An Online Non-Invasive Condition Monitoring Method for Stepping Motor CRDM in HTGR

    Directory of Open Access Journals (Sweden)

    S. Bakhri

    2016-12-01

    Full Text Available Control Rod Drive Mechanism (CRDM based on stepping motor is one of the components applied in High Temperature Gas Coold Reactor (HTGR to control the reactivity as well as to maintain the safety of reactor. The stepping motor requires a unique condition monitoring to avoid any failures especially due to the specific environments of CRDM in HTGR such as the allowable of high temperature, high radiation and the location of stepper motor inside a pressure shell. This research aims to demonstrate an online non-invasive condition monitoring method without direct access to the CRDM of HTGR based on voltage and stator current measurements. A simple stepping motor CRDM simulator is employed. The online condition monitoring is carried out by direct pattern matching of the output signals of logic generator block and the output signals of motor driver. The online method utilizes signature patterns of voltage and stator current signals of the healthy motor as a baseline for healthy motor. In addition, the method is applied to detect high-resistance problem on the connector between the motor driver block and the stepper motor to show the effectiveness and the applicability of this method. The online condition monitoring system demonstrates a capability to identify a minimum detectable simulated high-resistance for about 2.9% which decreases the measured stator current and motor’s torque for around 5.1% and 3.3%, respectively. The paper also points out signatures of healthy motor, including mutual inductions of the motor’s winding in voltage and current measurement which can be used as the fault symptom indicators for online monitoring purposes.

  4. Online Condition Monitoring of Gripper Cylinder in TBM Based on EMD Method

    Science.gov (United States)

    Li, Lin; Tao, Jian-Feng; Yu, Hai-Dong; Huang, Yi-Xiang; Liu, Cheng-Liang

    2017-11-01

    The gripper cylinder that provides braced force for Tunnel Boring Machine (TBM) might fail due to severe vibration when the TBM excavates in the tunnel. Early fault diagnosis of the gripper cylinder is important for the safety and efficiency of the whole tunneling project. In this paper, an online condition monitoring system based on the Empirical Mode Decomposition (EMD) method is established for fault diagnosis of the gripper cylinder while TBM is working. Firstly, the lumped mass parameter model of the gripper cylinder is established considering the influence of the variable stiffness at the rock interface, the equivalent stiffness of the oil, the seals, and the copper guide sleeve. The dynamic performance of the gripper cylinder is investigated to provide basis for its health condition evaluation. Then, the EMD method is applied to identify the characteristic frequencies of the gripper cylinder for fault diagnosis and a field test is used to verify the accuracy of the EMD method for detection of the characteristic frequencies. Furthermore, the contact stiffness at the interface between the barrel and the rod is calculated with Hertz theory and the relationship between the natural frequency and the stiffness varying with the health condition of the cylinder is simulated based on the dynamic model. The simulation shows that the characteristic frequencies decrease with the increasing clearance between the barrel and the rod, thus the defects could be indicated by monitoring the natural frequency. Finally, a health condition management system of the gripper cylinder based on the vibration signal and the EMD method is established, which could ensure the safety of TBM.

  5. An approximate method for solving a melting problem with periodic boundary conditions

    Directory of Open Access Journals (Sweden)

    Qu Liang-Hui

    2014-01-01

    Full Text Available An effective thermal diffusivity method is used to solve one-dimensional melting problem with periodic boundary conditions in a semi-infinite domain. An approximate analytic solution showing the functional relation between the location of the moving boundary and time is obtained by using Laplace transform. The evolution of the moving boundary and the temperature field in the phase change domain are simulated numerically, and the numerical results are compared with previous results in open literature.

  6. Approximate method for calculating heat conditions in the magnetic circuits of transformers and betatrons

    International Nuclear Information System (INIS)

    Loginov, V.S.

    1986-01-01

    A technique for engineering design of two-dimensional stationary temperature field of rectangular cross section blending pile with inner heat release under nonsymmetrical cooling conditions is suggested. Area of its practical application is determined on the basis of experimental data known in literature. Different methods for calculating temperature distribution in betatron magnetic circuit are compared. Graph of maximum temperature calculation error on the basis of approximated expressions with respect to exact solution is given

  7. Research on Condition Assessment Method of Transmission Tower Under the Action of Strong Wind

    Science.gov (United States)

    Huang, Ren-mou; An, Li-qiang; Zhang, Rong-lun; Wu, Jiong; Liang, Ya-feng

    2018-03-01

    Transmission towers are often subjected to the external damage of severe weather like strong wind and so on, which may cause the collapse due to the yield and fracture of the tower material. Aiming this issue, an assessment method was proposed in this paper to assess the operation condition of transmission towers under strong wind. With a reasonable assess index system established firstly, then the internal force of the tower material was solved and its stability was determined through the mechanical analysis of the transmission tower finite element model. Meanwhile, the condition risk level of the tower was finally determined by considering the difference among the influences of other factors like corrosion and loose of members, slope on the transmission tower through the analytic hierarchy process. The assessment method was applied to assess the wind-induced collapse of towers in 110kV Bao Yi II line in Wenchang City, Hainan Province, of which the result proves the method can assess the condition of transmission tower under strong wind and of guiding significance for improving the windproof capability of transmission towers.

  8. Wind Turbine Gearbox Condition Monitoring with AAKR and Moving Window Statistic Methods

    Directory of Open Access Journals (Sweden)

    Peng Guo

    2011-11-01

    Full Text Available Condition Monitoring (CM of wind turbines can greatly reduce the maintenance costs for wind farms, especially for offshore wind farms. A new condition monitoring method for a wind turbine gearbox using temperature trend analysis is proposed. Autoassociative Kernel Regression (AAKR is used to construct the normal behavior model of the gearbox temperature. With a proper construction of the memory matrix, the AAKR model can cover the normal working space for the gearbox. When the gearbox has an incipient failure, the residuals between AAKR model estimates and the measurement temperature will become significant. A moving window statistical method is used to detect the changes of the residual mean value and standard deviation in a timely manner. When one of these parameters exceeds predefined thresholds, an incipient failure is flagged. In order to simulate the gearbox fault, manual temperature drift is added to the initial Supervisory Control and Data Acquisitions (SCADA data. Analysis of simulated gearbox failures shows that the new condition monitoring method is effective.

  9. Sparse grid spectral methods for the numerical solution of partial differential equations with periodic boundary conditions

    International Nuclear Information System (INIS)

    Kupka, F.

    1997-11-01

    This thesis deals with the extension of sparse grid techniques to spectral methods for the solution of partial differential equations with periodic boundary conditions. A review on boundary and initial-boundary value problems and a discussion on numerical resolution is used to motivate this research. Spectral methods are introduced by projection techniques, and by three model problems: the stationary and the transient Helmholtz equations, and the linear advection equation. The approximation theory on the hyperbolic cross is reviewed and its close relation to sparse grids is demonstrated. This approach extends to non-periodic problems. Various Sobolev spaces with dominant mixed derivative are introduced to provide error estimates for Fourier approximation and interpolation on the hyperbolic cross and on sparse grids by means of Sobolev norms. The theorems are immediately applicable to the stability and convergence analysis of sparse grid spectral methods. This is explicitly demonstrated for the three model problems. A variant of the von Neumann condition is introduced to simplify the stability analysis of the time-dependent model problems. The discrete Fourier transformation on sparse grids is discussed together with its software implementation. Results on numerical experiments are used to illustrate the performance of the new method with respect to the smoothness properties of each example. The potential of the method in mathematical modelling is estimated and generalizations to other sparse grid methods are suggested. The appendix includes a complete Fortran90 program to solve the linear advection equation by the sparse grid Fourier collocation method and a third-order Runge-Kutta routine for integration in time. (author)

  10. Efficient enforcement of far-field boundary conditions in the Transformed Field Expansions method

    Science.gov (United States)

    Nicholls, David P.

    2011-09-01

    The Method of Transformed Field Expansions (TFE) has been demonstrated to be a robust and highly accurate numerical scheme for simulating solutions of boundary value and free boundary problems from the sciences and engineering. As a Boundary Perturbation Method it builds highly accurate solutions based upon exact solutions in a simple, canonical, geometry and corrects these via Taylor series to fit the actual geometry at hand. The TFE method has significantly enhanced stability properties when compared with other Boundary Perturbation approaches, however, this comes at the cost of requiring a full volumetric discretization as opposed the surface formulation that other methods can realize. In this paper we outline two techniques for ameliorating this shortcoming, first by employing a Legendre Spectral Element Method to implement efficient, graded meshes, and second by utilizing an Artificial Boundary with a Transparent Boundary Condition placed quite close to the boundary of the domain. In this contribution we focus on the specific problem of simulating the Dirichlet-Neumann operator associated to Laplace's equation on a periodic cell (which arises in the water wave problem). While the details of our results are specific to this problem, the general conclusions are valid for the wider class of problems to which the TFE method can be applied. For each technique we discuss implementation details and display numerical results which support the conclusion that each of these techniques can greatly reduce the computational cost of using the TFE method.

  11. A correction function method for the wave equation with interface jump conditions

    Science.gov (United States)

    Abraham, David S.; Marques, Alexandre Noll; Nave, Jean-Christophe

    2018-01-01

    In this paper a novel method to solve the constant coefficient wave equation, subject to interface jump conditions, is presented. In general, such problems pose issues for standard finite difference solvers, as the inherent discontinuity in the solution results in erroneous derivative information wherever the stencils straddle the given interface. Here, however, the recently proposed Correction Function Method (CFM) is used, in which correction terms are computed from the interface conditions, and added to affected nodes to compensate for the discontinuity. In contrast to existing methods, these corrections are not simply defined at affected nodes, but rather generalized to a continuous function within a small region surrounding the interface. As a result, the correction function may be defined in terms of its own governing partial differential equation (PDE) which may be solved, in principle, to arbitrary order of accuracy. The resulting scheme is not only arbitrarily high order, but also robust, having already seen application to Poisson problems and the heat equation. By extending the CFM to this new class of PDEs, the treatment of wave interface discontinuities in homogeneous media becomes possible. This allows, for example, for the straightforward treatment of infinitesimal source terms and sharp boundaries, free of staircasing errors. Additionally, new modifications to the CFM are derived, allowing compatibility with explicit multi-step methods, such as Runge-Kutta (RK4), without a reduction in accuracy. These results are then verified through numerous numerical experiments in one and two spatial dimensions.

  12. Evidence reasoning method for constructing conditional probability tables in a Bayesian network of multimorbidity.

    Science.gov (United States)

    Du, Yuanwei; Guo, Yubin

    2015-01-01

    The intrinsic mechanism of multimorbidity is difficult to recognize and prediction and diagnosis are difficult to carry out accordingly. Bayesian networks can help to diagnose multimorbidity in health care, but it is difficult to obtain the conditional probability table (CPT) because of the lack of clinically statistical data. Today, expert knowledge and experience are increasingly used in training Bayesian networks in order to help predict or diagnose diseases, but the CPT in Bayesian networks is usually irrational or ineffective for ignoring realistic constraints especially in multimorbidity. In order to solve these problems, an evidence reasoning (ER) approach is employed to extract and fuse inference data from experts using a belief distribution and recursive ER algorithm, based on which evidence reasoning method for constructing conditional probability tables in Bayesian network of multimorbidity is presented step by step. A multimorbidity numerical example is used to demonstrate the method and prove its feasibility and application. Bayesian network can be determined as long as the inference assessment is inferred by each expert according to his/her knowledge or experience. Our method is more effective than existing methods for extracting expert inference data accurately and is fused effectively for constructing CPTs in a Bayesian network of multimorbidity.

  13. Analýza dopadu tzv. daňové reformy na podnikatele FO

    OpenAIRE

    Tydlačková, Pavlína

    2008-01-01

    Bakalářská práce pojednává o daňových změnách týkající se podnikatelů FO, které souvisí s reformou veřejných financí. Obsahuje návody, postupy, praktické příklady a potřebné informace k pochopení změn a sestavení správného daňového přiznání. This bachelor’s thesis deals with the tax changes concerning a sole trader associated with a reform of public finance. It includes directions, procedures, practical examples and necessary informations to understanding changes and process correct declar...

  14. Investigation of a Superscalar Operand Stack Using FO4 and ASIC Wire-Delay Metrics

    Directory of Open Access Journals (Sweden)

    Christopher Bailey

    2014-01-01

    Full Text Available Complexity in processor microarchitecture and the related issues of power density, hot spots and wire delay, are seen to be a major concern for design migration into low nanometer technologies of the future. This paper evaluates the hardware cost of an alternative to register-file organization, the superscalar stack issue array (SSIA. We believe this is the first such reported study using discrete stack elements. Several possible implementations are evaluated, using a 90 nm standard cell library as a reference model, yielding delay data and FO4 metrics. The evaluation, including reference to ASIC layout, RC extraction, and timing simulation, suggests a 4-wide issue rate of at least four Giga-ops/sec at 90 nm and opportunities for twofold future improvement by using more advanced design approaches.

  15. What GRACE/GRACE-FO satellite gravity may tell about the atmosphere (and what not)

    Science.gov (United States)

    Eicker, Annette; Springer, Anne; Hense, Andreas; Panet, Isabelle; Kusche, Jürgen

    2017-04-01

    In this presentation we would like to discuss the present benefit and future potential of satellite gravity observations, as obtained from the satellite mission GRACE and its successor GRACE-Follow-On (GRACE-FO), for studying the atmospheric water cycle. In the first part of the presentation, we will show recent results of using GRACE to constrain atmospheric water budgets. GRACE-derived water storage changes (in combination with observed runoff) can be used to solve for the vertical water flux deficit of precipitation (P) minus evapotranspiration (E), which links the terrestrial and the atmospheric water balance equations. This relates gravity change to moisture flux divergence and water vapor change and thus provides, in principle, a link between GRACE/GRACE-FO and (area-averaged) GNSS integrated water vapor observations that may be exploited in the future. We will show that such an independent estimate of P minus E can be used to constrain land-atmosphere fluxes from monthly time scales to decadal trends and even provides meaningful flux information down to daily time steps. In the second part of the presentation, we would like to give an outlook towards the potential of using satellite gravity data directly for the estimation of atmospheric water mass changes. On the basis of ERA-Interim data, we provide a first assessment which suggests that an anticipated future double-pair gravity mission with enhanced temporal and spatial resolution would be sensitive to 'feeling' atmospheric water mass (water vapor) variations. However, whether these (faster) variations could be separated from dry air mass variations through modeling needs to be investigated. If possible, this would offer a completely new tool for validating atmospheric analyses and for improving engergy and mass budgets in models.

  16. What Can be Expected from the GRACE-FO Laser Ranging Interferometer for Earth Science Applications?

    Science.gov (United States)

    Flechtner, Frank; Neumayer, Karl-Hans; Dahle, Christoph; Dobslaw, Henryk; Fagiolini, Elisa; Raimondo, Jean-Claude; Güntner, Andreas

    2016-03-01

    The primary objective of the gravity recovery and climate experiment follow-on (GRACE-FO) satellite mission, due for launch in August 2017, is to continue the GRACE time series of global monthly gravity field models. For this, evolved versions of the GRACE microwave instrument, GPS receiver, and accelerometer will be used. A secondary objective is to demonstrate the effectiveness of a laser ranging interferometer (LRI) in improving the satellite-to-satellite tracking measurement performance. In order to investigate the expected enhancement for Earth science applications, we have performed a full-scale simulation over the nominal mission lifetime of 5 years using a realistic orbit scenario and error assumptions both for instrument and background model errors. Unfiltered differences between the synthetic input and the finally recovered time-variable monthly gravity models show notable improvements with the LRI, on a global scale, of the order of 23 %. The gain is realized for wavelengths smaller than 240 km in case of Gaussian filtering but decreases to just a few percent when anisotropic filtering is applied. This is also confirmed for some typical regional Earth science applications which show randomly distributed patterns of small improvements but also degradations when using DDK4-filtered LRI-based models. Analysis of applied error models indicates that accelerometer noise followed by ocean tide and non-tidal mass variation errors are the main contributors to the overall GRACE-FO gravity model error. Improvements in these fields are therefore necessary, besides optimized constellations, to make use of the increased LRI accuracy and to significantly improve gravity field models from next-generation gravity missions.

  17. Methods of body orientation in space in the absence of support under weightless conditions

    Science.gov (United States)

    Yeremin, A. V.; Stepantsov, V. I.; Chekidra, I. F.; Borisenko, I. P.; Kolosov, I. A.

    1975-01-01

    The experience accumulated in training subjects in methods of body orientation in space indicates the necessity of clear planning of the training process. After theoretical familiarization with the principles of body orientation in space and reviewing training films, practical mastery of the body orientation methods begins with working out of the individual elements on the Zhukovskiy stool. Then, the correctness and sequence of movements are carefully mastered in water, and the motor skills are then reinforced under time deficit conditions, on the vaulting bars, trampolines, and, in the concluding stage of training, the methods of orienting the body in space in weightlessness are worked out in laboratory-aircraft, with and without the spacesuit and with and without a load.

  18. Thermal Analysis of Reinforced Concrete Tank for Conditioning Wood by FEM Method

    Science.gov (United States)

    Błaszczyński, Tomasz; Babiak, Michał; Wielentejczyk, Przemysław

    2017-10-01

    The article introduces the analysis of a RC tank for conditioning wood carried out using the FEM (Finite Element Method). A temperature gradient distribution increase resulting from the influence of hot liquid filling the tank was defined. Values of gradients in border sections of the tank walls and the bottom were defined on the basis of the isotherm method. The obtained results were compared with empirical formulas from literature. Strength analyses were also carried out. Additionally, the problematic aspects of elongated monolithic tanks for liquids were introduced, especially regarding large temperature gradients and the means of necessary technical solutions. The use of the FEM method for designing engineering objects is, nowadays, an irreplaceable solution. In the case of the discussed tank, a spatial model of the construction mapping its actual performance was constructed in order to correctly estimate the necessary dimensions of wall and bottom sections, as well as reinforcement.

  19. Methods for locating ground faults and insulation degradation condition in energy conversion systems

    Science.gov (United States)

    Agamy, Mohamed; Elasser, Ahmed; Galbraith, Anthony William; Harfman Todorovic, Maja

    2015-08-11

    Methods for determining a ground fault or insulation degradation condition within energy conversion systems are described. A method for determining a ground fault within an energy conversion system may include, in part, a comparison of baseline waveform of differential current to a waveform of differential current during operation for a plurality of DC current carrying conductors in an energy conversion system. A method for determining insulation degradation within an energy conversion system may include, in part, a comparison of baseline frequency spectra of differential current to a frequency spectra of differential current transient at start-up for a plurality of DC current carrying conductors in an energy conversion system. In one embodiment, the energy conversion system may be a photovoltaic system.

  20. Four chemical methods of porcelain conditioning and their influence over bond strength and surface integrity

    Science.gov (United States)

    Stella, João Paulo Fragomeni; Oliveira, Andrea Becker; Nojima, Lincoln Issamu; Marquezan, Mariana

    2015-01-01

    OBJECTIVE: To assess four different chemical surface conditioning methods for ceramic material before bracket bonding, and their impact on shear bond strength and surface integrity at debonding. METHODS: Four experimental groups (n = 13) were set up according to the ceramic conditioning method: G1 = 37% phosphoric acid etching followed by silane application; G2 = 37% liquid phosphoric acid etching, no rinsing, followed by silane application; G3 = 10% hydrofluoric acid etching alone; and G4 = 10% hydrofluoric acid etching followed by silane application. After surface conditioning, metal brackets were bonded to porcelain by means of the Transbond XP system (3M Unitek). Samples were submitted to shear bond strength tests in a universal testing machine and the surfaces were later assessed with a microscope under 8 X magnification. ANOVA/Tukey tests were performed to establish the difference between groups (α= 5%). RESULTS: The highest shear bond strength values were found in groups G3 and G4 (22.01 ± 2.15 MPa and 22.83 ± 3.32 Mpa, respectively), followed by G1 (16.42 ± 3.61 MPa) and G2 (9.29 ± 1.95 MPa). As regards surface evaluation after bracket debonding, the use of liquid phosphoric acid followed by silane application (G2) produced the least damage to porcelain. When hydrofluoric acid and silane were applied, the risk of ceramic fracture increased. CONCLUSIONS: Acceptable levels of bond strength for clinical use were reached by all methods tested; however, liquid phosphoric acid etching followed by silane application (G2) resulted in the least damage to the ceramic surface. PMID:26352845

  1. A new method for the analysis of soft tissues with data acquired under field conditions.

    Directory of Open Access Journals (Sweden)

    Ruth S Sonnweber

    Full Text Available Analyzing soft-tissue structures is particularly challenging due to the lack of homologous landmarks that can be reliably identified across time and specimens. This is particularly true when data are to be collected under field conditions. Here, we present a method that combines photogrammetric techniques and geometric morphometrics methods (GMM to quantify soft tissues for their subsequent volumetric analysis. We combine previously developed methods for landmark data acquisition and processing with a custom program for volumetric computations. Photogrammetric methods are a particularly powerful tool for field studies as they allow for image acquisition with minimal equipment requirements and for the acquisition of the spatial coordinates of points (anatomical landmarks or others from these images. For our method, a limited number of homologous landmarks, i.e., points that can be found on any specimen independent of space and time, and further distinctive points, which may vary over time, space and subject, are identified on two-dimensional photographs and their three-dimensional coordinates estimated using photogrammetric methods. The three-dimensional configurations are oriented by the spatial principal components (PCs of the homologous points. Crucially, this last step orients the configuration such that x and y-information (PC1 and PC2 coordinates constitute an anatomically-defined plane with the z-values (PC3 coordinate in the direction of interest for volume computation. The z-coordinates are then used to estimate the volume of the tissue. We validate our method using a physical, geometric model of known dimensions and physical (wax models designed to approximate perineal swellings in female macaques. To demonstrate the usefulness and potential of our method, we use it to estimate the volumes of Barbary macaque sexual swellings recorded in the field with video images. By analyzing both the artificial data and real monkey swellings, we

  2. Rapid and tunable method to temporally control gene editing based on conditional Cas9 stabilization.

    Science.gov (United States)

    Senturk, Serif; Shirole, Nitin H; Nowak, Dawid G; Corbo, Vincenzo; Pal, Debjani; Vaughan, Alexander; Tuveson, David A; Trotman, Lloyd C; Kinney, Justin B; Sordella, Raffaella

    2017-02-22

    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. In particular, when co-expressed with inducible Cre-ER T2 , our system enables parallel, independent manipulation of alleles targeted by Cas9 and traditional recombinase with single-cell specificity. We anticipate this platform will be used for the systematic characterization and identification of essential genes, as well as the investigation of the interactions between functional genes.

  3. Simplified calculation method for radiation dose under normal condition of transport

    International Nuclear Information System (INIS)

    Watabe, N.; Ozaki, S.; Sato, K.; Sugahara, A.

    1993-01-01

    In order to estimate radiation dose during transportation of radioactive materials, the following computer codes are available: RADTRAN, INTERTRAN, J-TRAN. Because these codes consist of functions for estimating doses not only under normal conditions but also in the case of accidents, when nuclei may leak and spread into the environment by air diffusion, the user needs to have special knowledge and experience. In this presentation, we describe how, with a view to preparing a method by which a person in charge of transportation can calculate doses in normal conditions, the main parameters upon which the value of doses depends were extracted and the dose for a unit of transportation was estimated. (J.P.N.)

  4. Improvised purification methods for obtaining individual drinking water supply under war and extreme shortage conditions.

    Science.gov (United States)

    Kozlicic, A; Hadzic, A; Bevanda, H

    1994-01-01

    Supplying an adequate amount of drinking water to a population is a complex problem that becomes an extremely difficult task in war conditions. In this paper, several simple methods for obtaining individual supplies of drinking water by filtration of atmospheric water with common household items are reported. Samples of atmospheric water (rain and snow) were collected, filtered, and analyzed for bacteriological and chemical content. The ability of commonly available household materials (newspaper, filter paper, gauze, cotton, and white cotton cloth) to filter water from the environmental sources was compared. According to chemical and biological analysis, the best results were obtained by filtering melted snow from the ground through white cotton cloth. Atmospheric water collected during war or in extreme shortage conditions can be purified with simple improvised filtering techniques and, if chlorinated, used as an emergency potable water source.

  5. A Hybrid Maximum Power Point Search Method Using Temperature Measurements in Partial Shading Conditions

    Directory of Open Access Journals (Sweden)

    Mroczka Janusz

    2014-12-01

    Full Text Available Photovoltaic panels have a non-linear current-voltage characteristics to produce the maximum power at only one point called the maximum power point. In the case of the uniform illumination a single solar panel shows only one maximum power, which is also the global maximum power point. In the case an irregularly illuminated photovoltaic panel many local maxima on the power-voltage curve can be observed and only one of them is the global maximum. The proposed algorithm detects whether a solar panel is in the uniform insolation conditions. Then an appropriate strategy of tracking the maximum power point is taken using a decision algorithm. The proposed method is simulated in the environment created by the authors, which allows to stimulate photovoltaic panels in real conditions of lighting, temperature and shading.

  6. Method of bringing nuclear power plant to fractional electrical load conditions

    International Nuclear Information System (INIS)

    Iljunin, V.G.; Kuznetsoy, I.A.; Murogov, V.M.; Shmelev, A.N.

    1978-01-01

    A method is described of bringing a nuclear power plant to fractional electric load conditions, which power plant comprises at least two nuclear reactors, at least one nuclear reactor being a breeder and both reactors transferring heat to the turbine working substance, consisting in that the consumption of the turbine working substance is reduced in accordance with a predetermined fractional load. At the same time, the amount of heat being transferred from the nuclear reactors to the turbine working substance is reduced, for which purpose the reactors are included in autonomous cooling circuits to successively transfer heat to the turbine working substance. The breeding reactor is included in the cooling circuit with a lower coolant temperature, the temperature of the coolant at the inlet and outlet of the breeder being reduced to a level ensuring the operation of the nuclear power plant in predetermined fractional load conditions, due to which the power of the breeder is increased, and afterheat is removed

  7. A METHOD TO ESTIMATE TEMPORAL INTERACTION IN A CONDITIONAL RANDOM FIELD BASED APPROACH FOR CROP RECOGNITION

    Directory of Open Access Journals (Sweden)

    P. M. A. Diaz

    2016-06-01

    Full Text Available This paper presents a method to estimate the temporal interaction in a Conditional Random Field (CRF based approach for crop recognition from multitemporal remote sensing image sequences. This approach models the phenology of different crop types as a CRF. Interaction potentials are assumed to depend only on the class labels of an image site at two consecutive epochs. In the proposed method, the estimation of temporal interaction parameters is considered as an optimization problem, whose goal is to find the transition matrix that maximizes the CRF performance, upon a set of labelled data. The objective functions underlying the optimization procedure can be formulated in terms of different accuracy metrics, such as overall and average class accuracy per crop or phenological stages. To validate the proposed approach, experiments were carried out upon a dataset consisting of 12 co-registered LANDSAT images of a region in southeast of Brazil. Pattern Search was used as the optimization algorithm. The experimental results demonstrated that the proposed method was able to substantially outperform estimates related to joint or conditional class transition probabilities, which rely on training samples.

  8. An Intelligent Fleet Condition-Based Maintenance Decision Making Method Based on Multi-Agent

    Directory of Open Access Journals (Sweden)

    Bo Sun

    2012-01-01

    Full Text Available According to the demand for condition-based maintenance online decision making among a mission oriented fleet, an intelligent maintenance decision making method based on Multi-agent and heuristic rules is proposed. The process of condition-based maintenance within an aircraft fleet (each containing one or more Line Replaceable Modules based on multiple maintenance thresholds is analyzed. Then the process is abstracted into a Multi-Agent Model, a 2-layer model structure containing host negotiation and independent negotiation is established, and the heuristic rules applied to global and local maintenance decision making is proposed. Based on Contract Net Protocol and the heuristic rules, the maintenance decision making algorithm is put forward. Finally, a fleet consisting of 10 aircrafts on a 3-wave continuous mission is illustrated to verify this method. Simulation results indicate that this method can improve the availability of the fleet, meet mission demands, rationalize the utilization of support resources and provide support for online maintenance decision making among a mission oriented fleet.

  9. Cellular Neural Network Method for Critical Slab with Albedo Boundary Condition

    International Nuclear Information System (INIS)

    Pirouzmanda, A.; Hadada, K.; Suh, K. Y.

    2010-01-01

    The neutron transport problems have been studied theoretically and numerically for years. A number of researchers have studied the criticality problems of one-speed neutrons in homogeneous slabs and spheres using various methods. The Chebyshev polynomial approximation method (T N method) has lately been developed and improved for the neutron transport equation in slab geometry. The one-speed time-dependent neutron transport equation using the Cellular Neural Network (CNN) for the vacuum boundary condition has previously been solved. In this paper, we demonstrate the capacity of CNN in calculating the critical slab thickness for different boundary conditions and its variation with moments N. The architecture of the CNN has already been dealt with thoroughly. Essentially, the CNN is used to model a first-order system of the partial differential equations (PDEs). The original equations in the T N approximation are also a set of PDEs. The CNN approach lends itself to analog VLSI implementation. In this study, the CNN model is implemented using the HSpice software package

  10. Development of an aerosol microphysical module: Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS)

    Science.gov (United States)

    Matsui, H.; Koike, M.; Kondo, Y.; Fast, J. D.; Takigawa, M.

    2014-09-01

    Number concentrations, size distributions, and mixing states of aerosols are essential parameters for accurate estimations of aerosol direct and indirect effects. In this study, we develop an aerosol module, designated the Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS), that can explicitly represent these parameters by considering new particle formation (NPF), black carbon (BC) aging, and secondary organic aerosol (SOA) processes. A two-dimensional bin representation is used for particles with dry diameters from 40 nm to 10 μm to resolve both aerosol sizes (12 bins) and BC mixing states (10 bins) for a total of 120 bins. The particles with diameters between 1 and 40 nm are resolved using additional eight size bins to calculate NPF. The ATRAS module is implemented in the WRF-Chem model and applied to examine the sensitivity of simulated mass, number, size distributions, and optical and radiative parameters of aerosols to NPF, BC aging, and SOA processes over East Asia during the spring of 2009. The BC absorption enhancement by coating materials is about 50% over East Asia during the spring, and the contribution of SOA processes to the absorption enhancement is estimated to be 10-20% over northern East Asia and 20-35% over southern East Asia. A clear north-south contrast is also found between the impacts of NPF and SOA processes on cloud condensation nuclei (CCN) concentrations: NPF increases CCN concentrations at higher supersaturations (smaller particles) over northern East Asia, whereas SOA increases CCN concentrations at lower supersaturations (larger particles) over southern East Asia. The application of ATRAS in East Asia also shows that the impact of each process on each optical and radiative parameter depends strongly on the process and the parameter in question. The module can be used in the future as a benchmark model to evaluate the accuracy of simpler aerosol models and examine interactions between NPF, BC aging, and SOA

  11. Development of an aerosol microphysical module: Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS)

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, H.; Koike, Makoto; Kondo, Yutaka; Fast, Jerome D.; Takigawa, M.

    2014-09-30

    Number concentrations, size distributions, and mixing states of aerosols are essential parameters for accurate estimation of aerosol direct and indirect effects. In this study, we developed an aerosol module, designated Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS), that can represent these parameters explicitly by considering new particle formation (NPF), black carbon (BC) aging, and secondary organic aerosol (SOA) processes. A two-dimensional bin representation is used for particles with dry diameters from 40 nm to 10 µm to resolve both aerosol size (12 bins) and BC mixing state (10 bins) for a total of 120 bins. The particles with diameters from 1 to 40 nm are resolved using an additional 8 size bins to calculate NPF. The ATRAS module was implemented in the WRF-chem model and applied to examine the sensitivity of simulated mass, number, size distributions, and optical and radiative parameters of aerosols to NPF, BC aging and SOA processes over East Asia during the spring of 2009. BC absorption enhancement by coating materials was about 50% over East Asia during the spring, and the contribution of SOA processes to the absorption enhancement was estimated to be 10 – 20% over northern East Asia and 20 – 35% over southern East Asia. A clear north-south contrast was also found between the impacts of NPF and SOA processes on cloud condensation nuclei (CCN) concentrations: NPF increased CCN concentrations at higher supersaturations (smaller particles) over northern East Asia, whereas SOA increased CCN concentrations at lower supersaturations (larger particles) over southern East Asia. Application of ATRAS to East Asia also showed that the impact of each process on each optical and radiative parameter depended strongly on the process and the parameter in question. The module can be used in the future as a benchmark model to evaluate the accuracy of simpler aerosol models and examine interactions between NPF, BC aging, and SOA

  12. Setting the light conditions for measuring root transparency for age-at-death estimation methods.

    Science.gov (United States)

    Adserias-Garriga, Joe; Nogué-Navarro, Laia; Zapico, Sara C; Ubelaker, Douglas H

    2018-03-01

    Age-at-death estimation is one of the main goals in forensic identification, being an essential parameter to determine the biological profile, narrowing the possibility of identification in cases involving missing persons and unidentified bodies. The study of dental tissues has been long considered as a proper tool for age estimation with several age estimation methods based on them. Dental age estimation methods can be divided into three categories: tooth formation and development, post-formation changes, and histological changes. While tooth formation and growth changes are important for fetal and infant consideration, when the end of dental and skeletal growth is achieved, post-formation or biochemical changes can be applied. Lamendin et al. in J Forensic Sci 37:1373-1379, (1992) developed an adult age estimation method based on root transparency and periodontal recession. The regression formula demonstrated its accuracy of use for 40 to 70-year-old individuals. Later on, Prince and Ubelaker in J Forensic Sci 47(1):107-116, (2002) evaluated the effects of ancestry and sex and incorporated root height into the equation, developing four new regression formulas for males and females of African and European ancestry. Even though root transparency is a key element in the method, the conditions for measuring this element have not been established. The aim of the present study is to set the light conditions measured in lumens that offer greater accuracy when applying the Lamendin et al. method modified by Prince and Ubelaker. The results must be also taken into account in the application of other age estimation methodologies using root transparency to estimate age-at-death.

  13. Experimental Investigation of Pressure-volume-Temperature Mass Gauging Method Under Microgravity Condition by Parabolic Flight

    Science.gov (United States)

    Seo, Mansu; Park, Hana; Yoo, DonGyu; Jung, Youngsuk; Jeong, Sangkwon

    Gauging the volume or mass of liquid propellant of a rocket vehicle in space is an important issue for its economic feasibility and optimized design of loading mass. Pressure-volume-temperature (PVT) gauging method is one of the most suitable measuring techniques in space due to its simplicity and reliability. This paper presents unique experimental results and analyses of PVT gauging method using liquid nitrogen under microgravity condition by parabolic flight. A vacuum-insulated and cylindrical-shaped liquid nitrogen storage tank with 9.2 L volume is manufactured by observing regulation of parabolic flight. PVT gauging experiments are conducted under low liquid fraction condition from 26% to 32%. Pressure, temperature, and the injected helium mass into the storage tank are measured to obtain the ullage volume by gas state equation. Liquid volume is finally derived by the measured ullage volume and the known total tank volume. Two sets of parabolic flights are conducted and each set is composed of approximately 10 parabolic flights. In the first set of flights, the short initial waiting time (3 ∼ 5 seconds) cannot achieve sufficient thermal equilibrium condition at the beginning. It causes inaccurate gauging results due to insufficient information of the initial helium partial pressure in the tank. The helium injection after 12 second waiting time at microgravity condition with high mass flow rate in the second set of flights achieves successful initial thermal equilibrium states and accurate measurement results of initial helium partial pressure. Liquid volume measurement errors in the second set are within 11%.

  14. An Implementation of Hydrostatic Boundary Conditions for Variable Density Lattice Boltzmann Methods

    Science.gov (United States)

    Bardsley, K. J.; Thorne, D. T.; Lee, J. S.; Sukop, M. C.

    2006-12-01

    Lattice Boltzmann Methods (LBMs) have been under development for the last two decades and have become another capable numerical method for simulating fluid flow. Recent advances in lattice Boltzmann applications involve simulation of density-dependent fluid flow in closed (Dixit and Babu, 2006; D'Orazio et al., 2004) or periodic (Guo and Zhao, 2005) domains. However, standard pressure boundary conditions (BCs) are incompatible with concentration-dependent density flow simulations that use a body force for gravity. An implementation of hydrostatic BCs for use under these conditions is proposed here. The basis of this new implementation is an additional term in the pressure BC. It is derived to account for the incorporation of gravity as a body force and the effect of varying concentration in the fluid. The hydrostatic BC expands the potential of density-dependent LBM to simulate domains with boundaries other than the closed or periodic boundaries that have appeared in previous literature on LBM simulations. With this new implementation, LBM will be able to simulate complex concentration-dependent density flows, such as salt water intrusion in the classic Henry and Henry-Hilleke problems. This is demonstrated using various examples, beginning with a closed box system, and ending with a system containing two solid walls, one velocity boundary and one pressure boundary, as in the Henry problem. References Dixit, H. N., V. Babu, (2006), Simulation of high Rayleigh number natural convection in a square cavity using the lattice Boltzmann method, Int. J. Heat Mass Transfer, 49, 727-739. D'Orazio, A., M. Corcione, G.P. Celata, (2004), Application to natural convection enclosed flows of a lattice Boltzmann BGK model coupled with a general purpose thermal boundary conditions, Int. J. Thermal Sci., 43, 575-586. Gou, Z., T.S. Zhao, (2005), Lattice Boltzmann simulation of natural convection with temperature-dependant viscosity in a porous cavity, Numerical Heat Transfer, Part B

  15. Adaptive spacetime method using Riemann jump conditions for coupled atomistic-continuum dynamics

    Science.gov (United States)

    Kraczek, B.; Miller, S. T.; Haber, R. B.; Johnson, D. D.

    2010-03-01

    We combine the Spacetime Discontinuous Galerkin (SDG) method for elastodynamics with the mathematically consistent Atomistic Discontinuous Galerkin (ADG) method in a new scheme that concurrently couples continuum and atomistic models of dynamic response in solids. The formulation couples non-overlapping continuum and atomistic models across sharp interfaces by weakly enforcing jump conditions, for both momentum balance and kinematic compatibility, using Riemann values to preserve the characteristic structure of the underlying hyperbolic system. Momentum balances to within machine-precision accuracy over every element, on each atom, and over the coupled system, with small, controllable energy dissipation in the continuum region that ensures numerical stability. When implemented on suitable unstructured spacetime grids, the continuum SDG model offers linear computational complexity in the number of elements and powerful adaptive analysis capabilities that readily bridge between atomic and continuum scales in both space and time. A special trace operator for the atomic velocities and an associated atomistic traction field enter the jump conditions at the coupling interface. The trace operator depends on parameters that specify, at the scale of the atomic spacing, the position of the coupling interface relative to the atoms. In a key finding, we demonstrate that optimizing these parameters suppresses spurious reflections at the coupling interface without the use of non-physical damping or special boundary conditions. We formulate the implicit SDG-ADG coupling scheme in up to three spatial dimensions, and describe an efficient iterative solution scheme that outperforms common explicit schemes, such as the Velocity Verlet integrator. Numerical examples, in 1d×time and employing both linear and nonlinear potentials, demonstrate the performance of the SDG-ADG method and show how adaptive spacetime meshing reconciles disparate time steps and resolves atomic-scale signals

  16. Standard test method for damage to contacting solid surfaces under fretting conditions

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method covers the studying or ranking the susceptibility of candidate materials to fretting corrosion or fretting wear for the purposes of material selection for applications where fretting corrosion or fretting wear can limit serviceability. 1.2 This test method uses a tribological bench test apparatus with a mechanism or device that will produce the necessary relative motion between a contacting hemispherical rider and a flat counterface. The rider is pressed against the flat counterface with a loading mass. The test method is intended for use in room temperature air, but future editions could include fretting in the presence of lubricants or other environments. 1.3 The purpose of this test method is to rub two solid surfaces together under controlled fretting conditions and to quantify the damage to both surfaces in units of volume loss for the test method. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5...

  17. Peculiarities of homeostatic system in highland conditions using llizarov distraction transosseous osteosynthesis method

    Directory of Open Access Journals (Sweden)

    Jumabekov S.A.

    2012-06-01

    Full Text Available Purpose. The purpose is to study the reaction of homeostasis system in stable and in distraction llizarov transosseous ostesysnthesis of the limbs bones at experimental animals (dogs in highland conditions. Material and Methods. 63 adult mongrels aged from 1 to 3 years with 10-20 kg body weight and 15 cm minimal length of tibia were included in the experiment. Open osteosotmy of tibial mid-shaft followed by Kirschner wires insertion through tibial bone and llizarov frame assembly comprising 3 or 4 rings was performed under IV anaesthesia at 3200 m altitude above sea level. In experimental group including 33 mongrels the distraction was performed on the 5th day after osteotomy by 1 mm rate divided into 4 times within 10 days but in control group comprising 30 dogs the distraction was not provided. Every 10 days after distraction blood samples were taken in both groups to examine coagulation; the samples were taken from subcutaneous lateral tibial vein, ex tempora mixing with 3,8% solution of sodium citrate at 9:1 ratio. Then the plasma was separated and examined biochemically according to the accepted standards. Results. We obtained the data witnessing activation of coagulation component of homeostatic system in stable osteosynthesis of the limb bones using llizarov fixator with simultaneous inhibition of fibrinolytic component. In distraction osteosynthesis hyper-coagulation trend in homeostasis system with simultaneous suppression of fibrinolytic blood activity is vividly defined within the entire experiment period. Conclusion. Transosseous distraction osteosynthesis in highland condition causes considerable shifts in the system of homeostasis with definite domination of coagulation component which promotes formation of pre-thrombotic condition. Limb segment lengthening on the background of pre-thrombotic condition increases the risk of thromboembolic complications in highland conditions and requires appropriate measures of prophylaxis

  18. A probability evaluation method of early deterioration condition for the critical components of wind turbine generator systems

    DEFF Research Database (Denmark)

    Hu, Y.; Li, H.; Liao, X

    2016-01-01

    This study determines the early deterioration condition of critical components for a wind turbine generator system (WTGS). Due to the uncertainty nature of the fluctuation and intermittence of wind, early deterioration condition evaluation poses a challenge to the traditional vibration...... method of early deterioration condition for critical components based only on temperature characteristic parameters. First, the dynamic threshold of deterioration degree function was proposed by analyzing the operational data between temperature and rotor speed. Second, a probability evaluation method...... of early deterioration condition was presented. Finally, two cases showed the validity of the proposed probability evaluation method in detecting early deterioration condition and in tracking their further deterioration for the critical components....

  19. Effects of different surface conditioning methods on the bond strength of composite resin to amalgam.

    Science.gov (United States)

    Ozcan, M; Koolman, C; Aladag, A; Dündar, M

    2011-01-01

    Repairing amalgam restorations with composite resins using surface conditioning methods is a conservative treatment approach. This study investigated the effects of different conditioning methods that could be used for repair of amalgam fractures. Amalgam (N=96) was condensed into cavities within autopolymerizing polymethylmethacrylate (PMMA), and the exposed surface of each specimen (diameter, 6 mm; thickness, 2 mm) was ground finished. The specimens were randomly divided into nine experimental groups (n=12 per group), depending on the conditioning method used. The control group had natural central incisors with amalgam (n=12). The combination of the following conditioning methods was tested: silicacoating (Sc), sandblasting (Sb), metal primers, coupling agents, fiber (Fb) application, and opaquers (O). Five types of silanes, metal primers, or adhesives (Visiobond [V], Porcelain Photobond [PP], Alloy Primer [AP], Unibond sealer [Us], ESPE-Sil [ES]), and four opaquers, namely, Clearfil St Opaquer (CstO), Sinfony (S), Miris (M), and an experimental Opaquer (EO-Cavex), were used. The groups were as follows: group 1, Sc+ES+S+V; group 2, Sc+ES+CstO+V; group 3, Sc+ES+M+V; group 4, Sc+ES+EO+V; group 5, Sb+AP+S; group 6, Sb+AP+PP+CstO; group 7, Sc+ES+S+Fb+V+Fb; group 8-control, SC+ES+V; and group 9, Etch+Sc+ES+S+Us. One repair composite was used for all groups (Clearfil Photo Bond Posterior, Kuraray, Tokyo, Japan). Shear bond strengths (SBSs) (MPa ± SD) were evaluated after 5 weeks of water storage (analysis of variance [ANOVA], Tukey honestly significant differences [HSD], α=0.05). Group 1 exhibited significantly higher values (35.5 ± 4.1) than were seen in group 4 (19.4 ± 8.9), group 6 (19.1 ± 7.8), and group 8 (20.1 ± 4.1) (pcomposite adhesion to amalgam. Experimental opaquer exhibited lower values. Leaving a small border of enamel around the restoration decreased the bond strength.

  20. Applying Taguchi method for optimization of the synthesis condition of nano-porous alumina membrane by slip casting method

    Energy Technology Data Exchange (ETDEWEB)

    Barmala, Molood [Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Moheb, Ahmad, E-mail: ahmad@cc.iut.ac.i [Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Emadi, Rahmatollah [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2009-10-19

    In this work thin disc type pure alumina membranes have been prepared by slip casting technique. The colloidal stabilization of micro-sized alumina suspensions with different amount of 1,2-dihydroxy-3,5-benzenedisulfonic acid disodium salt (Tiron) at various suspension concentration were examined and the suspension stability was characterized by measuring sedimentation height. Also the necessary ball milling time (used as a deflocculating process) to prepare defect free membranes was investigated. A statistical experimental design method (Taguchi method with L9 orthogonal array design) was implemented to optimize experimental conditions for the preparation of Al{sub 2}O{sub 3} nano-porous membrane. Sintering temperature, solid content and polyvinyl alcohol (PVA) content were recognized and selected as important effecting parameters. Also structural studies by means of isopropanol adsorption and scanning electron microscopy were carried out on membranes. As the result of Taguchi analysis in this study, sintering temperature was the most influencing parameter on the membrane porosity. Reasonable membrane characteristics were obtained at an optimum temperature of 1400 deg. C, 20% solid content and 20 cc PVA solution per 100 g of alumina powder.

  1. An Invariant-Preserving ALE Method for Solids under Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sambasivan, Shiv Kumar [Los Alamos National Laboratory; Christon, Mark A [Los Alamos National Laboratory

    2012-07-17

    We are proposing a fundamentally new approach to ALE methods for solids undergoing large deformation due to extreme loading conditions. Our approach is based on a physically-motivated and mathematically rigorous construction of the underlying Lagrangian method, vector/tensor reconstruction, remapping, and interface reconstruction. It is transformational because it deviates dramatically from traditionally accepted ALE methods and provides the following set of unique attributes: (1) a three-dimensional, finite volume, cell-centered ALE framework with advanced hypo-/hyper-elasto-plastic constitutive theories for solids; (2) a new physically and mathematically consistent reconstruction method for vector/tensor fields; (3) advanced invariant-preserving remapping algorithm for vector/tensor quantities; (4) moment-of-fluid (MoF) interface reconstruction technique for multi-material problems with solids undergoing large deformations. This work brings together many new concepts, that in combination with emergent cell-centered Lagrangian hydrodynamics methods will produce a cutting-edge ALE capability and define a new state-of-the-art. Many ideas in this work are new, completely unexplored, and hence high risk. The proposed research and the resulting algorithms will be of immediate use in Eulerian, Lagrangian and ALE codes under the ASC program at the lab. In addition, the research on invariant preserving reconstruction/remap of tensor quantities is of direct interest to ongoing CASL and climate modeling efforts at LANL. The application space impacted by this work includes Inertial Confinement Fusion (ICF), Z-pinch, munition-target interactions, geological impact dynamics, shock processing of powders and shaped charges. The ALE framework will also provide a suitable test-bed for rapid development and assessment of hypo-/hyper-elasto-plastic constitutive theories. Today, there are no invariant-preserving ALE algorithms for treating solids with large deformations. Therefore

  2. METHODS FOR REPRESENTING THE TUBING OF VENTILATION/AIR-CONDITIONING PLANTS

    Directory of Open Access Journals (Sweden)

    MÂRZA Carmen

    2015-06-01

    Full Text Available The representation of ventilation or air conditioning plants, particularly of the tubing, specifically require the ability to "see into space" or, more completely expressed, to make the connection between the plane and the space. For this reason, in the study program of the "Building Services Engineering" these types of installations have a privileged role. Thus, the students learn the representation in 2D of these plants during the study of the discipline Technical Drawing and further they learn the representation methods in 2D and 3D using the AutoCAD software – respectively the subroutine CAD VENT. Finally, the undergraduates study - as an alternative - the axonometric representation of these plants, by using the Allplan software. The last one offers also elements of the tubes (pipes dimensioning. The paper presents teaching methods using concrete examples.

  3. FULL GPU Implementation of Lattice-Boltzmann Methods with Immersed Boundary Conditions for Fast Fluid Simulations

    Directory of Open Access Journals (Sweden)

    G Boroni

    2017-03-01

    Full Text Available Lattice Boltzmann Method (LBM has shown great potential in fluid simulations, but performance issues and difficulties to manage complex boundary conditions have hindered a wider application. The upcoming of Graphic Processing Units (GPU Computing offered a possible solution for the performance issue, and methods like the Immersed Boundary (IB algorithm proved to be a flexible solution to boundaries. Unfortunately, the implicit IB algorithm makes the LBM implementation in GPU a non-trivial task. This work presents a fully parallel GPU implementation of LBM in combination with IB. The fluid-boundary interaction is implemented via GPU kernels, using execution configurations and data structures specifically designed to accelerate each code execution. Simulations were validated against experimental and analytical data showing good agreement and improving the computational time. Substantial reductions of calculation rates were achieved, lowering down the required time to execute the same model in a CPU to about two magnitude orders.

  4. The future-oriented repetitive thought (FoRT) scale: A measure of repetitive thinking about the future.

    Science.gov (United States)

    Miranda, Regina; Wheeler, Alyssa; Polanco-Roman, Lillian; Marroquín, Brett

    2017-01-01

    Repetitive thinking about the future has been suggested as one way in which individuals may become hopeless about the future. We report on a new scale assessing future-oriented repetitive thinking, termed the Future-Oriented Repetitive Thought (FoRT) Scale. In Study 1, an exploratory factor analysis was conducted with data from 1071 individuals who completed the scale. Study 2 describes a confirmatory factor analysis with a revised version of the scale on a sample of 612 individuals, a subsample of whom (N=99) also completed measures of repetitive thought (rumination, worry), hopelessness-related cognitions, and symptoms of depression and generalized anxiety disorder in order to examine evidence for the measure's convergent, discriminant, and concurrent validity. Study 3 examined the scale's concurrent validity in distinguishing between individuals with and without a history of suicidal ideation and attempts. A three-factor solution emerged in Study 1, and this solution was confirmed in Study 2. In addition, the FoRT scale demonstrated moderate associations with other measures of repetitive thought (rumination, worry), with hopelessness-related cognitions, and with symptoms of depression and generalized anxiety. Finally, the FoRT scale distinguished between individuals with and without a history of suicidal ideation and attempts. Cross-sectional data limit conclusions that can be drawn about directionality. These findings suggest that the newly developed FoRT scale is a reliable and valid measure of future-oriented repetitive thought. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. A natural driven membrane process for brackish and wastewater treatment: photovoltaic powered ED and FO hybrid system.

    Science.gov (United States)

    Zhang, Yang; Pinoy, Luc; Meesschaert, Boudewijn; Van der Bruggen, Bart

    2013-09-17

    In isolated locations, remote areas, or islands, potable water is precious because of the lack of drinking water treatment facilities and energy supply. Thus, a robust and reliable water treatment system based on natural energy is needed to reuse wastewater or to desalinate groundwater/seawater for provision of drinking water. In this work, a hybrid membrane system combining electrodialysis (ED) and forward osmosis (FO), driven by renewable energy (solar energy), denoted as EDFORD (ED-FO Renewable energy Desalination), is proposed to produce high-quality water (potable) from secondary wastewater effluent or brackish water. In this hybrid membrane system, feedwater (secondary wastewater effluent or synthetic brackish water) was drawn to the FO draw solution while the organic and inorganic substances (ions, compounds, colloids and particles) were rejected. The diluted draw solution was then pumped to the solar energy driven ED. In the ED unit, the diluted draw solution was desalted and high-quality water was produced; the concentrate was recycled to the FO unit and reused as the draw solution. Results show that the water produced from this system contains a low concentration of total organic carbon (TOC), carbonate, and cations derived from the feedwater; had a low conductivity; and meets potable water standards. The water production cost considering the investment for membranes and solar panel is 3.32 to 4.92 EUR m(-3) (for 300 days of production per year) for a small size potable water production system.

  6. A new method for estimating UV fluxes at ground level in cloud-free conditions

    Science.gov (United States)

    Wandji Nyamsi, William; Pitkänen, Mikko R. A.; Aoun, Youva; Blanc, Philippe; Heikkilä, Anu; Lakkala, Kaisa; Bernhard, Germar; Koskela, Tapani; Lindfors, Anders V.; Arola, Antti; Wald, Lucien

    2017-12-01

    A new method has been developed to estimate the global and direct solar irradiance in the UV-A and UV-B at ground level in cloud-free conditions. It is based on a resampling technique applied to the results of the k-distribution method and the correlated-k approximation of Kato et al. (1999) over the UV band. Its inputs are the aerosol properties and total column ozone that are produced by the Copernicus Atmosphere Monitoring Service (CAMS). The estimates from this new method have been compared to instantaneous measurements of global UV irradiances made in cloud-free conditions at five stations at high latitudes in various climates. For the UV-A irradiance, the bias ranges between -0.8 W m-2 (-3 % of the mean of all data) and -0.2 W m-2 (-1 %). The root mean square error (RMSE) ranges from 1.1 W m-2 (6 %) to 1.9 W m-2 (9 %). The coefficient of determination R2 is greater than 0.98. The bias for UV-B is between -0.04 W m-2 (-4 %) and 0.08 W m-2 (+13 %) and the RMSE is 0.1 W m-2 (between 12 and 18 %). R2 ranges between 0.97 and 0.99. This work demonstrates the quality of the proposed method combined with the CAMS products. Improvements, especially in the modeling of the reflectivity of the Earth's surface in the UV region, are necessary prior to its inclusion into an operational tool.

  7. Improvement of basal conditions knowledge in Antarctica using data assimilation methods

    Science.gov (United States)

    Mosbeux, C.; Gillet-Chaulet, F.; Gagliardini, O.

    2017-12-01

    The current global warming seems to have direct consequences on ice-sheet mass loss. Unfortunately, as highlighted in the last IPCC report, current ice-sheets models face several difficulties in assessing the future evolution of the dynamics of ice sheets for the next century. Indeed, projections are still plagued with high uncertainties partially due to the poor representation of occurring physical processes, but also due to the poor initialisation of ice flow models. More specifically, simulations are very sensitive to initial parameters such as the basal friction between ice-sheet and bedrock and the bedrock topography which are still badly known because of a lack of direct observations or large uncertainty on measurements. Improving the knowledge of these two parameters in Greenland and Antarctica is therefore a prerequisite for making reliable projections. Data assimilation methods have been developed in order to overcome this problem such as the Bayesian approach of Pralong and Gudmundsson (2009) or the adjoint method tested by Goldberg and Heimbach (2013) and Perego et al. (2014). The present work is based on two different assimilation algorithms to better constrain both basal drag and bedrock elevation parameters. The first algorithm is entirely based on the adjoint method while the second one uses an iterative method coupling inversion of basal friction based on an adjoint method and through an inversion of bedrock topography using a nudging method. Both algorithms have been implemented in the finite element ice sheet and ice flow model Elmer/Ice and have been tested in a twin experiment showing a clear improvement of both parameters knowledge (Mosbeux et al., 2016). Here, the methods are applied to a real 3D case in East Antarctica and with an ensemble method approach. The application of both algorithms reduces the uncertainty on basal conditions, for instance by providing more details to the basal geometry when compared to usual DEM. Moreover, as in the

  8. An optimization method for condition based maintenance of aircraft fleet considering prognostics uncertainty.

    Science.gov (United States)

    Feng, Qiang; Chen, Yiran; Sun, Bo; Li, Songjie

    2014-01-01

    An optimization method for condition based maintenance (CBM) of aircraft fleet considering prognostics uncertainty is proposed. The CBM and dispatch process of aircraft fleet is analyzed first, and the alternative strategy sets for single aircraft are given. Then, the optimization problem of fleet CBM with lower maintenance cost and dispatch risk is translated to the combinatorial optimization problem of single aircraft strategy. Remain useful life (RUL) distribution of the key line replaceable Module (LRM) has been transformed into the failure probability of the aircraft and the fleet health status matrix is established. And the calculation method of the costs and risks for mission based on health status matrix and maintenance matrix is given. Further, an optimization method for fleet dispatch and CBM under acceptable risk is proposed based on an improved genetic algorithm. Finally, a fleet of 10 aircrafts is studied to verify the proposed method. The results shows that it could realize optimization and control of the aircraft fleet oriented to mission success.

  9. Effects of Different Extraction Methods and Conditions on the Phenolic Composition of Mate Tea Extracts

    Directory of Open Access Journals (Sweden)

    Jelena Vladic

    2012-03-01

    Full Text Available A simple and rapid HPLC method for determination of chlorogenic acid (5-O-caffeoylquinic acid in mate tea extracts was developed and validated. The chromatography used isocratic elution with a mobile phase of aqueous 1.5% acetic acid-methanol (85:15, v/v. The flow rate was 0.8 mL/min and detection by UV at 325 nm. The method showed good selectivity, accuracy, repeatability and robustness, with detection limit of 0.26 mg/L and recovery of 97.76%. The developed method was applied for the determination of chlorogenic acid in mate tea extracts obtained by ethanol extraction and liquid carbon dioxide extraction with ethanol as co-solvent. Different ethanol concentrations were used (40, 50 and 60%, v/v and liquid CO2 extraction was performed at different pressures (50 and 100 bar and constant temperature (27 ± 1 °C. Significant influence of extraction methods, conditions and solvent polarity on chlorogenic acid content, antioxidant activity and total phenolic and flavonoid content of mate tea extracts was established. The most efficient extraction solvent was liquid CO2 with aqueous ethanol (40% as co-solvent using an extraction pressure of 100 bar.

  10. Convergence analysis of the rebalance methods in multiplying finite slab having periodic boundary conditions

    International Nuclear Information System (INIS)

    Hong, Ser Gi; Lee, Young Ouk; Song, Jae Seung

    2009-01-01

    This paper analyzes the convergence of the rebalance iteration methods for the discrete ordinates transport equation in the multiplying finite slab problem. The finite slab is assumed to be homogeneous and it has the periodic boundary conditions. A general formulation is used to include three well-known rebalance methods of the linearized form in a unified way. The rebalance iteration methods considered in this paper are the CMR (Coarse-Mesh Rebalance), the CMFD (Coarse-Mesh Finite Difference), and p-CMFD (Partial Current-Based Coarse Mesh Finite Difference) methods which have been popularly used in the reactor physics. The convergence analysis is performed with the well-known Fourier analysis through a linearization. The analyses are applied for one-group problems. The theoretical analysis shows that there are one fundamental mode and N-1 Eigen-modes which determine the convergence if the finite slab is divided into N uniform meshes. The numerical tests show that the Fourier convergence analysis provides the reasonable estimate of the numerical spectral radii for the model problems and the spectral radius for the finite slab approaches the one for the infinite slab as the thickness of the slab increases. (author)

  11. A Stabilized Incompressible SPH Method by Relaxing the Density Invariance Condition

    Directory of Open Access Journals (Sweden)

    Mitsuteru Asai

    2012-01-01

    Full Text Available A stabilized Incompressible Smoothed Particle Hydrodynamics (ISPH is proposed to simulate free surface flow problems. In the ISPH, pressure is evaluated by solving pressure Poisson equation using a semi-implicit algorithm based on the projection method. Even if the pressure is evaluated implicitly, the unrealistic pressure fluctuations cannot be eliminated. In order to overcome this problem, there are several improvements. One is small compressibility approach, and the other is introduction of two kinds of pressure Poisson equation related to velocity divergence-free and density invariance conditions, respectively. In this paper, a stabilized formulation, which was originally proposed in the framework of Moving Particle Semi-implicit (MPS method, is applied to ISPH in order to relax the density invariance condition. This formulation leads to a new pressure Poisson equation with a relaxation coefficient, which can be estimated by a preanalysis calculation. The efficiency of the proposed formulation is tested by a couple of numerical examples of dam-breaking problem, and its effects are discussed by using several resolution models with different particle initial distances. Also, the effect of eddy viscosity is briefly discussed in this paper.

  12. PERT: A Method for Expression Deconvolution of Human Blood Samples from Varied Microenvironmental and Developmental Conditions

    Science.gov (United States)

    Csaszar, Elizabeth; Yu, Mei; Morris, Quaid; Zandstra, Peter W.

    2012-01-01

    The cellular composition of heterogeneous samples can be predicted using an expression deconvolution algorithm to decompose their gene expression profiles based on pre-defined, reference gene expression profiles of the constituent populations in these samples. However, the expression profiles of the actual constituent populations are often perturbed from those of the reference profiles due to gene expression changes in cells associated with microenvironmental or developmental effects. Existing deconvolution algorithms do not account for these changes and give incorrect results when benchmarked against those measured by well-established flow cytometry, even after batch correction was applied. We introduce PERT, a new probabilistic expression deconvolution method that detects and accounts for a shared, multiplicative perturbation in the reference profiles when performing expression deconvolution. We applied PERT and three other state-of-the-art expression deconvolution methods to predict cell frequencies within heterogeneous human blood samples that were collected under several conditions (uncultured mono-nucleated and lineage-depleted cells, and culture-derived lineage-depleted cells). Only PERT's predicted proportions of the constituent populations matched those assigned by flow cytometry. Genes associated with cell cycle processes were highly enriched among those with the largest predicted expression changes between the cultured and uncultured conditions. We anticipate that PERT will be widely applicable to expression deconvolution strategies that use profiles from reference populations that vary from the corresponding constituent populations in cellular state but not cellular phenotypic identity. PMID:23284283

  13. Optimization of Coolant Technique Conditions for Machining A319 Aluminium Alloy Using Response Surface Method (RSM)

    Science.gov (United States)

    Zainal Ariffin, S.; Razlan, A.; Ali, M. Mohd; Efendee, A. M.; Rahman, M. M.

    2018-03-01

    Background/Objectives: The paper discusses about the optimum cutting parameters with coolant techniques condition (1.0 mm nozzle orifice, wet and dry) to optimize surface roughness, temperature and tool wear in the machining process based on the selected setting parameters. The selected cutting parameters for this study were the cutting speed, feed rate, depth of cut and coolant techniques condition. Methods/Statistical Analysis Experiments were conducted and investigated based on Design of Experiment (DOE) with Response Surface Method. The research of the aggressive machining process on aluminum alloy (A319) for automotive applications is an effort to understand the machining concept, which widely used in a variety of manufacturing industries especially in the automotive industry. Findings: The results show that the dominant failure mode is the surface roughness, temperature and tool wear when using 1.0 mm nozzle orifice, increases during machining and also can be alternative minimize built up edge of the A319. The exploration for surface roughness, productivity and the optimization of cutting speed in the technical and commercial aspects of the manufacturing processes of A319 are discussed in automotive components industries for further work Applications/Improvements: The research result also beneficial in minimizing the costs incurred and improving productivity of manufacturing firms. According to the mathematical model and equations, generated by CCD based RSM, experiments were performed and cutting coolant condition technique using size nozzle can reduces tool wear, surface roughness and temperature was obtained. Results have been analyzed and optimization has been carried out for selecting cutting parameters, shows that the effectiveness and efficiency of the system can be identified and helps to solve potential problems.

  14. Microclimate design methods for energy-saving houses on various site conditions in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Kyeong

    2008-07-09

    A small area can have several different microclimates depending on how much sunlight, shade or wind are exposed on the area. Microclimate can be influenced by inclined terrain, surfaces, and 3-dimensionally geometry such as combinations of architectural elements and annex buildings. This study investigates microclimate modification for energy-saving using design elements of Korean traditional and passive house. Microclimate analysis method in this study enables to predict temporal and spatial variances in the building geometry. A combination of passive solar heating, cold wind blocking, indoor air circulation, natural ventilation cooling and shading etc, seasonally help to form a comfort condition with less energy consumption. The passive heating and cooling controls with microclimate modification are efficient to accomplish the energy efficiency in the building. This work includes the microclimate modifications of the high-performance designs, microclimate energy-saving methods, Passive House design methods, and common physical bases in energy simulation methods. For hot and humid summer in Korea, ventilation is beneficial for convective or evaporative cooling. The air flow through a building geometry is generated by differences in air temperature and pressure. The layout of surrounding buildings acts as barriers and diverts the flow into narrower. The resulted patterns of airflow are affected more by building geometry and orientation than by air speed. A novel simulation method combining multi-zone and CFD energy simulations is used to analyze energy-saving aspects in passive and microclimate design elements. EnergyPlus is a multi-zone energy simulation tool that uses a parameterization to simplify the energy-saving problem for each zone. However, the model is not appropriate to handle variations in the building geometry since it estimates only the average value for each volume. On the contrary, CFD method with subdivided grid units is more suitable to estimate

  15. Kinetics of the reaction of F atoms with O2 and UV spectrum of FO2 radicals in the gas phase at 295 K

    DEFF Research Database (Denmark)

    Ellermann, T.; Sehested, J.; Nielsen, O.J.

    1994-01-01

    The ultraviolet absorption spectrum of FO2 radicals and the kinetics of the reaction of F atoms with O2 have been studied in the gas phase at 295 K using pulse radiolysis combined with kinetic UV spectroscopy. At 230 nm, sigma(FO2) = (5.08 +/- 0.70) X 10(-18) cm2 molecule-1. The kinetics...

  16. New Evidence That Nonlinear Source-Filter Coupling Affects Harmonic Intensity and fo Stability During Instances of Harmonics Crossing Formants.

    Science.gov (United States)

    Maxfield, Lynn; Palaparthi, Anil; Titze, Ingo

    2017-03-01

    The traditional source-filter theory of voice production describes a linear relationship between the source (glottal flow pulse) and the filter (vocal tract). Such a linear relationship does not allow for nor explain how changes in the filter may impact the stability and regularity of the source. The objective of this experiment was to examine what effect unpredictable changes to vocal tract dimensions could have on fo stability and individual harmonic intensities in situations in which low frequency harmonics cross formants in a fundamental frequency glide. To determine these effects, eight human subjects (five male, three female) were recorded producing fo glides while their vocal tracts were artificially lengthened by a section of vinyl tubing inserted into the mouth. It was hypothesized that if the source and filter operated as a purely linear system, harmonic intensities would increase and decrease at nearly the same rates as they passed through a formant bandwidth, resulting in a relatively symmetric peak on an intensity-time contour. Additionally, fo stability should not be predictably perturbed by formant/harmonic crossings in a linear system. Acoustic analysis of these recordings, however, revealed that harmonic intensity peaks were asymmetric in 76% of cases, and that 85% of fo instabilities aligned with a crossing of one of the first four harmonics with the first three formants. These results provide further evidence that nonlinear dynamics in the source-filter relationship can impact fo stability as well as harmonic intensities as harmonics cross through formant bandwidths. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  17. The unified method: II. NLS on the half-line with t-periodic boundary conditions

    International Nuclear Information System (INIS)

    Lenells, J; Fokas, A S

    2012-01-01

    Boundary value problems for integrable nonlinear evolution PDEs formulated on the half-line can be analyzed by the unified method introduced by one of the authors and used extensively in the literature. The implementation of this general method to this particular class of problems yields the solution in terms of the unique solution of a matrix Riemann–Hilbert problem formulated in the complex k-plane (the Fourier plane), which has a jump matrix with explicit (x, t)-dependence involving four scalar functions of k, called spectral functions. Two of these functions depend on the initial data, whereas the other two depend on all boundary values. The most difficult step of the new method is the characterization of the latter two spectral functions in terms of the given initial and boundary data, i.e. the elimination of the unknown boundary values. For certain boundary conditions, called linearizable, this can be achieved by simply using algebraic manipulations. Here, we first present an effective characterization of the spectral functions in terms of the given initial and boundary data for the general case of non-linearizable boundary conditions. This characterization is based on the analysis of the so-called global relation and on the introduction of the so-called Gelfand–Levitan–Marchenko representations of the eigenfunctions defining the spectral functions. We then concentrate on the physically significant case of t-periodic Dirichlet boundary data. After presenting certain heuristic arguments which suggest that the Neumann boundary values become periodic as t → ∞, we show that for the case of the NLS with a sine-wave as Dirichlet data, the asymptotics of the Neumann boundary values can be computed explicitly at least up to third order in a perturbative expansion and indeed at least up to this order are asymptotically periodic. (paper)

  18. Combining geoelectrical and advanced lysimeter methods to characterize heterogeneous flow and transport under unsaturated transient conditions

    Science.gov (United States)

    Wehrer, M.; Skowronski, J.; Binley, A. M.; Slater, L. D.

    2013-12-01

    Our ability to predict flow and transport processes in the unsaturated critical zone is considerably limited by two characteristics: heterogeneity of flow and transience of boundary conditions. The causes of heterogeneous - or preferential - flow and transport are fairly well understood, yet the characterization and quantification of such processes in natural profiles remains challenging. This is due to current methods of observation, such as staining and isotope tracers, being unable to observe multiple events on the same profile and offering limited spatial information. In our study we demonstrate an approach to characterize preferential flow and transport processes applying a combination of geoelectrical methods and advanced lysimeter techniques. On an agricultural soil profile, which was transferred undisturbed into a lysimeter container, we applied systematically varied input flow boundary conditions, resembling natural precipitation events. We simultaneously measured the breakthrough of a conservative tracer. Flow and transport in the soil column were observed using electrical resistivity tomography (ERT), tensiometers, water content probes and a multicompartment suction plate (MSP). These techniques allowed a direct ground-truthing of soil moisture and pore fluid resistivity changes estimated noninvasively using ERT. We were able to image both the advancing infiltration front and the advancing tracer front using time lapse ERT. Water content changes associated with the advancing infiltration front dominated over pore fluid conductivity changes during short term precipitation events. Conversely, long term displacement of the solute front was monitored during periods of constant water content in between infiltration events. We observed preferential flow phenomena through ERT and through the MSP, which agreed in general terms. The preferential flow fraction was observed to be independent of precipitation rate. This suggests the presence of a fingering process

  19. An improved segmentation-based HMM learning method for Condition-based Maintenance

    International Nuclear Information System (INIS)

    Liu, T; Lemeire, J; Cartella, F; Meganck, S

    2012-01-01

    In the domain of condition-based maintenance (CBM), persistence of machine states is a valid assumption. Based on this assumption, we present an improved Hidden Markov Model (HMM) learning algorithm for the assessment of equipment states. By a good estimation of initial parameters, more accurate learning can be achieved than by regular HMM learning methods which start with randomly chosen initial parameters. It is also better in avoiding getting trapped in local maxima. The data is segmented with a change-point analysis method which uses a combination of cumulative sum charts (CUSUM) and bootstrapping techniques. The method determines a confidence level that a state change happens. After the data is segmented, in order to label and combine the segments corresponding to the same states, a clustering technique is used based on a low-pass filter or root mean square (RMS) values of the features. The segments with their labelled hidden state are taken as 'evidence' to estimate the parameters of an HMM. Then, the estimated parameters are served as initial parameters for the traditional Baum-Welch (BW) learning algorithms, which are used to improve the parameters and train the model. Experiments on simulated and real data demonstrate that both performance and convergence speed is improved.

  20. A mixed-grid finite element method with PML absorbing boundary conditions for seismic wave modelling

    International Nuclear Information System (INIS)

    Liu, Shaolin; Li, Xiaofan; Liu, Youshan; Wang, Wenshuai

    2014-01-01

    We have developed a mixed-grid finite element method (MGFEM) to simulate seismic wave propagation in 2D structurally complex media. This method divides the physical domain into two subdomains. One subdomain covering the major part of the physical domain is divided by regular quadrilateral elements, while the other subdomain uses triangular elements to correctly fit a rugged free surface topography. The local stiffness matrix of any quadrilateral element is identical and matrix-vector production is calculated using an element-by-element technique, which avoids assembling a huge global stiffness matrix. As only a few triangular elements exist in the subdomain containing the rugged free surface topography, the memory requirements for storing the assembled subdomain global stiffness matrix are significantly reduced. To eliminate artificial boundary reflections, the MGFEM is also implemented to solve the system equations of PML absorbing boundary conditions (PML ABC). The accuracy and efficiency of the MGFEM is tested in numerical experiments by comparing it with conventional methods, and numerical comparisons also indicate its tremendous ability to describe rugged surfaces. (paper)

  1. The theory and method of variable frequency directional seismic wave under the complex geologic conditions

    Science.gov (United States)

    Jiang, T.; Yue, Y.

    2017-12-01

    It is well known that the mono-frequency directional seismic wave technology can concentrate seismic waves into a beam. However, little work on the method and effect of variable frequency directional seismic wave under complex geological conditions have been done .We studied the variable frequency directional wave theory in several aspects. Firstly, we studied the relation between directional parameters and the direction of the main beam. Secondly, we analyzed the parameters that affect the beam width of main beam significantly, such as spacing of vibrator, wavelet dominant frequency, and number of vibrator. In addition, we will study different characteristics of variable frequency directional seismic wave in typical velocity models. In order to examine the propagation characteristics of directional seismic wave, we designed appropriate parameters according to the character of direction parameters, which is capable to enhance the energy of the main beam direction. Further study on directional seismic wave was discussed in the viewpoint of power spectral. The results indicate that the energy intensity of main beam direction increased 2 to 6 times for a multi-ore body velocity model. It showed us that the variable frequency directional seismic technology provided an effective way to strengthen the target signals under complex geological conditions. For concave interface model, we introduced complicated directional seismic technology which supports multiple main beams to obtain high quality data. Finally, we applied the 9-element variable frequency directional seismic wave technology to process the raw data acquired in a oil-shale exploration area. The results show that the depth of exploration increased 4 times with directional seismic wave method. Based on the above analysis, we draw the conclusion that the variable frequency directional seismic wave technology can improve the target signals of different geologic conditions and increase exploration depth with little

  2. A comparative analysis of Painleve, Lax pair, and similarity transformation methods in obtaining the integrability conditions of nonlinear Schroedinger equations

    International Nuclear Information System (INIS)

    Al Khawaja, U.

    2010-01-01

    We derive the integrability conditions of nonautonomous nonlinear Schroedinger equations using the Lax pair and similarity transformation methods. We present a comparative analysis of these integrability conditions with those of the Painleve method. We show that while the Painleve integrability conditions restrict the dispersion, nonlinearity, and dissipation/gain coefficients to be space independent and the external potential to be only a quadratic function of position, the Lax Pair and the similarity transformation methods allow for space-dependent coefficients and an external potential that is not restricted to the quadratic form. The integrability conditions of the Painleve method are retrieved as a special case of our general integrability conditions. We also derive the integrability conditions of nonautonomous nonlinear Schroedinger equations for two- and three-spacial dimensions.

  3. Environmental and economic assessment of hybrid FO-RO/NF system with selected inorganic draw solutes for the treatment of mine impaired water

    KAUST Repository

    Kim, Jung Eun

    2018-01-01

    A hybrid forward osmosis (FO) and reverse osmosis (RO)/nanofiltration (NF) system in a closed-loop operation with selected draw solutes was evaluated to treat coal mine impaired water. This study provides an insight of selecting the most suitable draw solution (DS) by conducting environmental and economic life cycle assessment (LCA). Baseline environmental LCA showed that the dominant components to energy use and global warming are the DS recovery processes (i.e. RO or NF processes) and FO membrane materials, respectively. When considering the DS replenishment in FO, the contribution of chemical use to the overall global warming impact was significant for all hybrid systems. Furthermore, from an environmental perspective, the FO-NF hybrid system with Na2SO4 shows the lowest energy consumption and global warming with additional considerations of final product water quality and FO brine disposal. From an economic perspective, the FO-NF with Na2SO4 showed the lowest total operating cost due to its lower DS loss and relatively low solute cost. In a closed-loop system, FO-NF with NaCl and Na2SO4 had the lowest total water cost at optimum NF recovery rates of 90 and 95%, respectively. FO-NF with Na2SO4 had the lowest environmental and economic impacts. Overall, draw solute performances and cost in FO and recovery rate in RO/NF play a crucial role in determining the total water cost and environmental impact of FO hybrid systems in a closed-loop operation.

  4. A hybrid measure-correlate-predict method for long-term wind condition assessment

    International Nuclear Information System (INIS)

    Zhang, Jie; Chowdhury, Souma; Messac, Achille; Hodge, Bri-Mathias

    2014-01-01

    Highlights: • A hybrid measure-correlate-predict (MCP) methodology with greater accuracy is developed. • Three sets of performance metrics are proposed to evaluate the hybrid MCP method. • Both wind speed and direction are considered in the hybrid MCP method. • The best combination of MCP algorithms is determined. • The developed hybrid MCP method is uniquely helpful for long-term wind resource assessment. - Abstract: This paper develops a hybrid measure-correlate-predict (MCP) strategy to assess long-term wind resource variations at a farm site. The hybrid MCP method uses recorded data from multiple reference stations to estimate long-term wind conditions at a target wind plant site with greater accuracy than is possible with data from a single reference station. The weight of each reference station in the hybrid strategy is determined by the (i) distance and (ii) elevation differences between the target farm site and each reference station. In this case, the wind data is divided into sectors according to the wind direction, and the MCP strategy is implemented for each wind direction sector separately. The applicability of the proposed hybrid strategy is investigated using five MCP methods: (i) the linear regression; (ii) the variance ratio; (iii) the Weibull scale; (iv) the artificial neural networks; and (v) the support vector regression. To implement the hybrid MCP methodology, we use hourly averaged wind data recorded at five stations in the state of Minnesota between 07-01-1996 and 06-30-2004. Three sets of performance metrics are used to evaluate the hybrid MCP method. The first set of metrics analyze the statistical performance, including the mean wind speed, wind speed variance, root mean square error, and mean absolute error. The second set of metrics evaluate the distribution of long-term wind speed; to this end, the Weibull distribution and the Multivariate and Multimodal Wind Distribution models are adopted. The third set of metrics analyze

  5. Application of GPR and seismic methods in landslides investigation and determination of hydrogeological conditions

    Science.gov (United States)

    Czaja, Klaudia; Matuła, Rafał

    2013-04-01

    verify GPR interpretation seismic measurements was performed. The basic assumption of the applicability of seismic methods is the existance of a distinct boundary between two lithological horizons defined by a change in material density and elastic modulus, which results in an increase or a decrase in wave velocity. Seismic refraction and MASW (multichannel analysis of surface waves) were the main methods. Geophones with frequencies 4 Hz and 10 Hz were used. Topographical variations were included during interpretation. It is possible to correlate GPR and seismic results especially during localization of water saturation zones. All applied methods gave also satisfactory results in recognition of the hydrogeological conditions.

  6. Assessment of Wind Turbine for Site-Specific Conditions using Probabilistic Methods

    DEFF Research Database (Denmark)

    Heras, Enrique Gómez de las; Gutiérrez, Roberto; Azagra, Elena

    2013-01-01

    This paper describes a new approach to assess the structural integrity of wind turbines for sitespecific conditions using probabilistic methods, taking into account the particular uncertainties associated to each site. This new approach intends to improve the site suitability analysis of wind...... state equation is defined making the loads and resistance depending on a set of stochastic variables representing the uncertainties. In this paper, special focus is put on the uncertainties related to the assessment of wind data, which is the main input for the sitespecific load assessment, and can...... be very dependent on the site. The uncertainties on the wind properties depend on issues like the available wind data, the quality of the measurement sensors, the type of terrain or the accuracy of the engineering models for horizontal and vertical spatial extrapolation. An example is included showing two...

  7. Methods for improved forewarning of condition changes in monitoring physical processes

    Science.gov (United States)

    Hively, Lee M.

    2013-04-09

    This invention teaches further improvements in methods for forewarning of critical events via phase-space dissimilarity analysis of data from biomedical equipment, mechanical devices, and other physical processes. One improvement involves objective determination of a forewarning threshold (U.sub.FW), together with a failure-onset threshold (U.sub.FAIL) corresponding to a normalized value of a composite measure (C) of dissimilarity; and providing a visual or audible indication to a human observer of failure forewarning and/or failure onset. Another improvement relates to symbolization of the data according the binary numbers representing the slope between adjacent data points. Another improvement relates to adding measures of dissimilarity based on state-to-state dynamical changes of the system. And still another improvement relates to using a Shannon entropy as the measure of condition change in lieu of a connected or unconnected phase space.

  8. Chemical method of labelling proteins with the radionuclides of technetium at physiological condition

    International Nuclear Information System (INIS)

    Wong, D.W.

    1983-01-01

    A novel rapid chemical method of labeling plasma proteins, other compounds and/or substances containing protein with radionuclides of technetium such as sup(95m)Tc, sup(99m)Tc or sup(99)Tc at physiologic pH 7.4 condition, producing a sterile non-pyrogenic radioactive tracer material suitable for biological and medical uses. These radiolabeled protein substances are not denatured by the labeling process but retain their natural physiological and immunological properties. This novel labeling technique provides a simple and rapid means of labeling plasma proteins such as human serum albumin, fibrinogen, antibodies, hormones and enzymes with sup(95m)Tc or sup(99m)Tc for scintigraphic imaging which may allow visualization of thrombi, emboli, myocardial infarcts, infectious lesions or tumors

  9. Simplified Method for Modeling the Impact of Arbitrary Partial Shading Conditions on PV Array Performance: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    MacAlpine, Sara; Deline, Chris

    2015-09-15

    It is often difficult to model the effects of partial shading conditions on PV array performance, as shade losses are nonlinear and depend heavily on a system's particular configuration. This work describes and implements a simple method for modeling shade loss: a database of shade impact results (loss percentages), generated using a validated, detailed simulation tool and encompassing a wide variety of shading scenarios. The database is intended to predict shading losses in crystalline silicon PV arrays and is accessed using basic inputs generally available in any PV simulation tool. Performance predictions using the database are within 1-2% of measured data for several partially shaded PV systems, and within 1% of those predicted by the full, detailed simulation tool on an annual basis. The shade loss database shows potential to considerably improve performance prediction for partially shaded PV systems.

  10. Selection of development and working methods of coal seams in complicated mining and geological conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kaufman, L.L.; Bakhtin, A.F.; Zel' vyanskii, M.Sh. (Donetskaya Proektnaya Kontora (USSR))

    1991-07-01

    Presents the design and technological patterns developed at the Donetsk Design Office for planning mining work in difficult mining conditions. The recommended patterns of working are based on the following principles. The most progressive panel development of mine-take and horizon layout methods are used. The main workings are driven as rock drifts with support pillars or they are driven in stress relaxed zones. Seams are worked with pillars or in a combined way. The pillarless technology is based on conducting workings with coal cutting along the excavated space or on repeated utilization of workings. Reduction in stone hoisting to the surface is achieved by execution of drifts that follow the longwalls. Variants of pillar systems with panel development of mine-take and horizon layout development are shown and described.

  11. A method of inferring collision ratio based on maneuverability of own ship under critical collision conditions

    Directory of Open Access Journals (Sweden)

    Youngjun You

    2013-06-01

    Full Text Available In constructing a collision avoidance system, it is important to determine the time for starting collision avoidance maneuver. Many researchers have attempted to formulate various indices by applying a range of techniques. Among these indices, collision risk obtained by combining Distance to the Closest Point of Approach (DCPA and Time to the Closest Point of Approach (TCPA information with fuzzy theory is mostly used. However, the collision risk has a limit, in that membership functions of DCPA and TCPA are empirically determined. In addition, the collision risk is not able to consider several critical collision conditions where the target ship fails to take appropriate actions. It is therefore necessary to design a new concept based on logical approaches. In this paper, a collision ratio is proposed, which is the expected ratio of unavoidable paths to total paths under suitably characterized operation conditions. Total paths are determined by considering categories such as action space and methodology of avoidance. The International Regulations for Preventing Collisions at Sea (1972 and collision avoidance rules (2001 are considered to solve the slower ship's dilemma. Different methods which are based on a constant speed model and simulated speed model are used to calculate the relative positions between own ship and target ship. In the simulated speed model, fuzzy control is applied to determination of command rudder angle. At various encounter situations, the time histories of the collision ratio based on the simulated speed model are compared with those based on the constant speed model.

  12. Note on the Physical Basis of the Kutta Condition in Unsteady Two-Dimensional Panel Methods

    Directory of Open Access Journals (Sweden)

    M. La Mantia

    2015-01-01

    Full Text Available Force generation in avian and aquatic species is of considerable interest for possible engineering applications. The aim of this work is to highlight the theoretical and physical foundations of a new formulation of the unsteady Kutta condition, which postulates a finite pressure difference at the trailing edge of the foil. The condition, necessary to obtain a unique solution and derived from the unsteady Bernoulli equation, implies that the energy supplied for the wing motion generates trailing-edge vortices and their overall effect, which depends on the motion initial parameters, is a jet of fluid that propels the wing. The postulated pressure difference (the value of which should be experimentally obtained models the trailing-edge velocity difference that generates the thrust-producing jet. Although the average thrust values computed by the proposed method are comparable to those calculated by assuming null pressure difference at the trailing edge, the latter (commonly used approach is less physically meaningful than the present one, as there is a singularity at the foil trailing edge. Additionally, in biological applications, that is, for autonomous flapping, the differences ought to be more significant, as the corresponding energy requirements should be substantially altered, compared to the studied oscillatory motions.

  13. A method of inferring collision ratio based on maneuverability of own ship under critical collision conditions

    Science.gov (United States)

    You, Youngjun; Rhee, Key-Pyo; Ahn, Kyoungsoo

    2013-06-01

    In constructing a collision avoidance system, it is important to determine the time for starting collision avoidance maneuver. Many researchers have attempted to formulate various indices by applying a range of techniques. Among these indices, collision risk obtained by combining Distance to the Closest Point of Approach (DCPA) and Time to the Closest Point of Approach (TCPA) information with fuzzy theory is mostly used. However, the collision risk has a limit, in that membership functions of DCPA and TCPA are empirically determined. In addition, the collision risk is not able to consider several critical collision conditions where the target ship fails to take appropriate actions. It is therefore necessary to design a new concept based on logical approaches. In this paper, a collision ratio is proposed, which is the expected ratio of unavoidable paths to total paths under suitably characterized operation conditions. Total paths are determined by considering categories such as action space and methodology of avoidance. The International Regulations for Preventing Collisions at Sea (1972) and collision avoidance rules (2001) are considered to solve the slower ship's dilemma. Different methods which are based on a constant speed model and simulated speed model are used to calculate the relative positions between own ship and target ship. In the simulated speed model, fuzzy control is applied to determination of command rudder angle. At various encounter situations, the time histories of the collision ratio based on the simulated speed model are compared with those based on the constant speed model.

  14. Fruit Leathers: Method of Preparation and Effect of Different Conditions on Qualities

    Directory of Open Access Journals (Sweden)

    Lemuel M. Diamante

    2014-01-01

    Full Text Available Fruit leathers are dehydrated fruit products which are eaten as snacks or desserts. They are flexible sheets that have a concentrated fruit flavor and nutritional aspects. Most fruit leathers are prepared by mixing fruit puree and other additives like sugar, pectin, acid, glucose syrup, color, and potassium metabisulphite and then dehydrating them under specific conditions. Various drying systems including combined convective and far-infrared drying, hot air drying, microwave drying, solar drying, and sun drying have been used to make fruit leathers. Most fruit leathers are dried at 30 to 80°C for up to 24 hours until the target final moisture content (12–20% has been reached. Research about fruit leathers began in the 1970s. This work has reviewed published papers on fruit leathers in order to summarize useful information about fruit leathers on methods of preparation, effects of drying condition, and effects of packaging and storage, which will be useful to many in the food industry and consumers who are health-conscious.

  15. Fruit Leathers: Method of Preparation and Effect of Different Conditions on Qualities

    Science.gov (United States)

    Diamante, Lemuel M.; Bai, Xue; Busch, Janette

    2014-01-01

    Fruit leathers are dehydrated fruit products which are eaten as snacks or desserts. They are flexible sheets that have a concentrated fruit flavor and nutritional aspects. Most fruit leathers are prepared by mixing fruit puree and other additives like sugar, pectin, acid, glucose syrup, color, and potassium metabisulphite and then dehydrating them under specific conditions. Various drying systems including combined convective and far-infrared drying, hot air drying, microwave drying, solar drying, and sun drying have been used to make fruit leathers. Most fruit leathers are dried at 30 to 80°C for up to 24 hours until the target final moisture content (12–20%) has been reached. Research about fruit leathers began in the 1970s. This work has reviewed published papers on fruit leathers in order to summarize useful information about fruit leathers on methods of preparation, effects of drying condition, and effects of packaging and storage, which will be useful to many in the food industry and consumers who are health-conscious. PMID:26904618

  16. Classifying running speed conditions using a single wearable sensor: Optimal segmentation and feature extraction methods.

    Science.gov (United States)

    Benson, Lauren C; Clermont, Christian A; Osis, Sean T; Kobsar, Dylan; Ferber, Reed

    2018-04-11

    Accelerometers have been used to classify running patterns, but classification accuracy and computational load depends on signal segmentation and feature extraction. Stride-based segmentation relies on identifying gait events, a step avoided by using window-based segmentation. For each segment, discrete points can be extracted from the accelerometer signal, or advanced features can be computed. Therefore, the purpose of this study was to examine how different segmentation and feature extraction methods influence the accuracy and computational load of classifying running conditions. Forty-four runners ran at their preferred speed and 25% faster than preferred while an accelerometer at the lower back recorded 3D accelerations. Computational load was determined as the accelerometer signal was segmented into single and five strides, and corresponding small and large windows, with discrete points extracted from the single stride segments and advanced features computed from all four segment types. Each feature set was used to classify speed conditions and classification accuracy was recorded. Computational load and classification accuracy were compared across all feature sets using a repeated-measures MANOVA, with follow-up t-tests to compare feature type (discrete vs. advanced), segmentation method (stride- vs. window-based), and segment size (small vs. large), using a Bonferroni-adjusted α = 0.003. The five-stride (97.49 (±4.57)%) and large-window advanced (97.23 (±5.51)%) feature sets produced the greatest classification accuracy, but the large-window advanced feature set had a lower computational load (0.0041 (±0.0002)s) than the stride-based feature sets. Therefore, using a few advanced features and large overlapping window sizes yields the best performance of both classification accuracy and computational load. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Time-series photometry of FO Aquarii's 2016 and 2017 low states

    Science.gov (United States)

    Littlefield, Colin; Garnavich, Peter; Kennedy, Mark; American Asssociation of Variable Star Observers

    2018-01-01

    For decades prior to 2016, the intermediate polar FO Aquarii had been observed exclusively in a state of high mass transfer, but in two separate low states in 2016 and 2017, the mass-transfer rate plummeted, causing the system to fade by over 2 magnitudes in the first event and 1 magnitude in the second. During the nine months separating the two low states, the system's brightness stabilized at V~13.75, approximately 0.25 mag fainter than it was before the 2016 event. Power spectral analysis shows that during the first low state, the dominant short-term modulation was at twice the spin-orbit beat frequency, implying that a substantial fraction of the accretion occurred via direct interaction between the accretion stream and the white dwarf's magnetosphere. Near the end of the recovery from the low state, there was a pronounced transition back to the spin-pulse-dominated light curve normally seen in the high state. During the subsequent low state in 2017, the strongest signal in the power spectrum was the beat frequency itself. Furthermore, in both low states, the light curves exhibit irregular flaring episodes that correlate with changes in the power spectrum. Finally, we examine how the eclipse profile became narrower and shallower during the two faint states.

  18. Soil tillage and water infiltration in semi-arid Morocco: the role fo surface and sub-surface soil conditions

    NARCIS (Netherlands)

    Dimanche, P.H.; Hoogmoed, W.B.

    2002-01-01

    Production of cereals in a dryland farming system forms an important part of agricultural production in Morocco. Yield levels on the Saïs Plateau between Meknès and Fez in the semi-arid zone, however, remain low possibly because of sub-optimum water use due to inefficient tillage systems. A study

  19. A Joint Positioning and Attitude Solving Method for Shearer and Scraper Conveyor under Complex Conditions

    Directory of Open Access Journals (Sweden)

    Jiacheng Xie

    2017-01-01

    Full Text Available In a fully mechanized coal-mining face, the positioning and attitude of the shearer and scraper conveyor are inaccurate. To overcome this problem, a joint positioning and attitude solving method that considers the effect of an uneven floor is proposed. In addition, the real-time connection and coupling relationship between the two devices is analyzed. Two types of sensors, namely, the tilt sensor and strapdown inertial navigation system (SINS, are used to measure the shearer body pitch angle and the scraper conveyor shape, respectively. To improve the accuracy, two pieces of information are fused using the adaptive information fusion algorithm. It is observed that, using a marking strategy, the shearer body pitch angle can be reversely mapped to the real-time shape of the scraper conveyor. Then, a virtual-reality (VR software that can visually simulate this entire operation process under different conditions is developed. Finally, experiments are conducted on a prototype experimental platform. The positioning error is found to be less than 0.38 times the middle trough length; moreover, no accumulated error is detected. This method can monitor the operation of the shearer and scraper conveyor in a highly dynamic and precise manner and provide strong technical support for safe and efficient operation of a fully mechanized coal-mining face.

  20. Morphological Analysis of Dentin Surface after Conditioning with Two Different methods: Chemical and Mechanical.

    Science.gov (United States)

    Rafael, Caroline Freitas; Quinelato, Valquíria; Morsch, Carolina Schaffer; DeDeus, Gustavo; Reis, Claudia Mendonca

    2016-01-01

    Alternative pretreatment strategies of dentin and adhesionare constantly being developed and studied with the goal of improving the adhesion of resin restorative materials with this tissue. The objectives of the present study were to evaluate the ability of airborne-particle abrasion (APA) with aluminum oxide on dentin to remove the smear layer and the effects produced on the dentin microstructure. The phosphoric acid (PA) was used for a comparison. For that, 20 human third molars were randomly allocated into two experimental groups, according to the dentin pretreatment method used: G1 (N = 10) - PA, G2 (N = 10) -APA. For dentin surface analyses, an environmental scanning electron microscope (ESEM) was employed to observe dentin surfaces before and after the procedures. Before pretreatment, the specimens of both groups were smear covered. After pretreatment, the G1 images revealed dentin tubule orifices opened, enlarged and some erosive effects. (G2) exposed tubule orifices without enlargement, but crack-like alterations were observed on the surfaces. In this way, APA with aluminum oxide was able to remove the smear layer. The influences of the dentin roughness on adhesion and the consequences on dentin integrity and hardness need further investigations. A good conditioning of the dentin before cementation is necessary in order to obtain a satisfactory rehabilitation in adhesive dentistry. So, it is necessary to know all methods to do it.

  1. Effects of impregnation methods and drying conditions on quinoline hydrodenitrogenation over Ni-W based catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Fang; Qiu, Zegang; Zhao, Liangfu; Xiang, Hongwei [Institute of Coal Chemistry, Chinese Academy of Sciences (China); Guo, Shaoqing [Taiyuan University of Science and Technology (China)

    2014-04-15

    The effects of impregnation methods (co-impregnation and sequential impregnation) and drying conditions (air and vacuum) on the structure and catalytic behavior of MCM-41 supported Ni-W catalysts were investigated. The catalysts were characterized by powder X-ray diffraction (XRD) analysis, Fourier-transform infrared spectroscopy (FT-IR), diffuse reflectance UV-Vis absorbance spectroscopy (DRS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and pyridine adsorbed infrared spectroscopy (Py-IR) techniques. They were tested for hydrodenitrogenation (HDN) of quinoline at temperatures of 300-400 deg C. The HDN results showed that the catalysts prepared by co-impregnation were more active than the catalysts prepared by sequential impregnation and the catalysts prepared by drying under vacuum were more active than the catalysts dried in air. Characterization revealed that the co-impregnation method and drying under vacuum promoted the dispersion of W, the formation of the active phases, and the formation of acidic sites on the catalysts. (author)

  2. Simple Moving Voltage Average Incremental Conductance MPPT Technique with Direct Control Method under Nonuniform Solar Irradiance Conditions

    OpenAIRE

    Ali, Amjad; Li, Wuhua; He, Xiangning

    2015-01-01

    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...

  3. Fear of progression in patients 6 months after cancer rehabilitation-a- validation study of the fear of progression questionnaire FoP-Q-12.

    Science.gov (United States)

    Hinz, Andreas; Mehnert, Anja; Ernst, Jochen; Herschbach, Peter; Schulte, Thomas

    2015-06-01

    Many cancer patients experience fear of progression (FoP). The purpose of this study was to test psychometric properties of the questionnaire FoP-Q-12, to examine age and gender differences of FoP, and to explore prognostic factors of FoP. A sample of 2059 patients with a cancer diagnosis who had participated in a cancer rehabilitation program was examined 6 months after discharge from the rehabilitation clinic. Participants filled in the Fear of Progression questionnaire FoP-Q-12, the Hospital Anxiety and Depression Scale (anxiety subscale), and the Generalized Anxiety Disorder Questionnaire GAD-2 and answered a list of questions concerning their cancer disease. Reliability of the FoP-Q-12 (Cronbach's alpha = 0.90) was good. While exploratory factorial analysis supported the one-dimensional structure of the FoP-Q-12, confirmatory factorial analysis only partially supported the one-dimensional model. A proportion of 16.7 % of the sample scored above the FoP-Q-12 cutoff score. Females showed higher FoP scores than males (effect size d = 0.52), and older patients had slightly lower levels of FoP than younger patients (d = 0.17). There were substantial and significant correlations between FoP-Q-12 and Hospital Anxiety and Depression Scale (HADS) anxiety (r = 0.71) as well as GAD-2 anxiety (r = 0.57). The highest FoP mean scores were found for the following cancer locations: ovary (M = 29.5), thyroid gland (M = 28.8), and breast (M = 27.9), while the lowest scores were found for Hodgkin lymphoma (M = 23.6), testis (M = 21.8), and prostate (M = 21.7). The FoP-Q-12 proved to be a valid instrument for measuring fear of progression in cancer patients.

  4. Effect of conditioning methods on the microtensile bond strength of phosphate monomer-based cement on zirconia ceramic in dry and aged conditions

    NARCIS (Netherlands)

    Amaral, Regina; Ozcan, Mutlu; Valandro, Luiz Felipe; Balducci, Ivan; Bottino, Marco Antonio

    The objective of this study was to evaluate the durability of bond strength between a resin cement and aluminous ceramic submitted to various surface conditioning methods. Twenty-four blocks (5 X 5 X 4 mm 3) of a glass-in filtrated zirconia-alumina ceramic (inCeram Zirconia Classic) were randomly

  5. Cultural methods and environmental conditions affecting gray mold and its management in lisianthus.

    Science.gov (United States)

    Shpialter, Lena; David, Dalia Rav; Dori, Irit; Yermiahu, Uri; Pivonia, Shimon; Levite, Rahel; Elad, Yigal

    2009-05-01

    Gray mold, caused by Botrytis cinerea, severely affects the base of the stems of lisianthus (Eustoma grandiflorum) plants as well as the cut stems left after flowers are harvested. This study examined infection of lisianthus plants by B. cinerea under laboratory and commercial greenhouse production conditions typical for Israel and evaluated cultural methods for manipulating disease development in commercial greenhouses. Although the lower nodes of lisianthus stems are typically infected, in this study, the inherent susceptibility of these nodes was less than that of nodes midway up the stem. Greater light intensity (4,860 lux) was associated with significantly more severe stem wounds than lower light intensities of 140 to 1,020 lux. Lower light intensity (140 lux) was associated with significantly more severe leaf infection. The development of gray mold along leaves toward the stem was slower at 26 degrees C than at 18 to 20 degrees C and was fastest at relative humidity (RH) levels close to saturation (>99%). B. cinerea infection developed in all stem wounds exposed to 65 to 99% RH and at temperatures of 12 to 29 degrees C. Infection severity in stem wounds (measured as lesion length) on whole plants was significantly less at 26 degrees C than at 18 or 22 degrees C, and was significantly higher at 99% RH compared with 70 to 85 and 85 to 95% RH. Severity of gray mold was the greatest at 15 to 22 degrees C and 85 to 99% RH. Under commercial greenhouse conditions, supplemental calcium (Ca(NO3)2) applied in fertigation or as a spray led to moderate yet significant reduction in disease severity. In addition, polyethylene soil cover and the use of buried drip irrigation instead of surface drip irrigation suppressed gray mold significantly on cut stems following harvest. Covering the soil with polyethylene also suppressed gray mold significantly as compared with the common practice of growing lisianthus in bare soil.

  6. Evaluation of main control room habitability in Japanese LWR (1). Outline of evaluation method and conditions

    International Nuclear Information System (INIS)

    Fujita, Yuko; Yoneda, Jiro; Okabayashi, Kazuki; Fukuda, Ryo

    2009-01-01

    It has been recognized that main control room habitability (CRH) is very important safety item. Its evaluation method and conditions was recently updated as a common method both for Boiling Water Reactor (BWR) and Pressurized Water Reactor (PWR) in Japan. This paper describes the common procedure for CRH evaluation. Postulated accidents for CRH evaluation are Loss of Coolant Accident (LOCA) for BWR and PWR, Main Steam Line Break Accident(MSLBA) for BWR, and Steam Generator Tube Rupture(SGTR) for PWR. Evaluation period is thirty days after each accident occurs. Acceptable criterion for each operator is 100mSv as total effective dose equivalent for thirty days, considering the net staying period of an operator in a control room and frequency of alternation of working staff. Total effective dose equivalent is calculated not only for an operator in control room, but also for an operator outside a building for alternation, and then total effective dose is compared with the criterion. The routes for dose evaluation are classified into five patterns, covering three patterns of location of radioactive source (i.e. source inside a building, source released into air, and source leaked into a control room) and covering two patterns of location of an operator (i.e. in control room and outside a building for alternation). Total effective dose by a route for source which is released into air and leaked into a control room is typically the largest contributor, in case of PWR LOCA evaluation, as an example showing relatively severe result. Evaluated dose for this dominant route is significantly affected by two calculations. One is a source term for calculation of radioactive gas release and the other is dispersion calculation in the air for concentration of radioactive gas in the vicinity of a control room. For LOCA 100% Kr,Xe and 50% iodine of total core radionuclide inventory are assumed to be released immediately into containment vessel. This is the most conservative assumption

  7. Standard nomenclature and methods for describing the condition of pavements draft TRH 6

    CSIR Research Space (South Africa)

    Curtayne, PC

    2009-01-26

    Full Text Available The need for describing the condition of pavements occurs frequently in highway engineering. Accurate descriptions are a prerequisite for establishing procedures with which to evaluate the various aspects of the pavement condition. A variety...

  8. A new minimum fluorescence parameter, as generated using pulse frequency modulation, compared with pulse amplitude modulation: Falpha versus Fo.

    Science.gov (United States)

    Wright, A Harrison; DeLong, John M; Franklin, Jeffrey L; Lada, Rajasekaran R; Prange, Robert K

    2008-09-01

    The minimum fluorescence parameter (Falpha), generated using the new pulse frequency modulation (PFM) technology, was compared with the minimum fluorescence parameter (Fo), generated by pulse amplitude modulation (PAM), in response to a reversible low-oxygen stress in 'Honeycrisp'trade mark (HC) apples (Malus domestica) and an irreversible osmotic stress induced by water loss in two grape (Vitis spp.) cultivars ('L'Acadie' (LAc) and 'Thompson Seedless' (TS)). The minimum fluorescence values produced by both fluorometer types in response to a reversible low-oxygen stress in apples were indistinguishable: both Fo and Falpha increased when O2 levels were lowered below the anaerobic compensation point (ACP); when gas levels returned to normoxia both parameters dipped below, then returned to, the original fluorescence baseline. The two parameters also responded similarly to the irreversible osmotic stress in grapes: in both cultivars, Falpha and Fo first decreased before reaching an inflection point at approximately 20% mass loss and then increased towards a second inflection point. However, the two parameters were not analogous under the irreversible osmotic stress; most notably, the relative Falpha values appeared to be lower than Fo during the later stages of dehydration. This was likely due to the influence of the Fm parameter and an overestimation of Falpha when measuring the fluorescence from healthy and responsive chloroplasts as found in grapes experiencing minimal water loss, but not in grapes undergoing moderate to severe dehydration. An examination of the data during a typical PFM scan reveals this fluorometer system may yield new fluorescence information with interesting biological applications.

  9. Development of an aerosol microphysical module: Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS)

    OpenAIRE

    H. Matsui; M. Koike; Y. Kondo; J. D. Fast; M. Takigawa

    2014-01-01

    Number concentrations, size distributions, and mixing states of aerosols are essential parameters for accurate estimation of aerosol direct and indirect effects. In this study, we develop an aerosol module, designated Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS), that can represent these parameters explicitly by considering new particle formation (NPF), black carbon (BC) aging, and secondary organic aerosol (SOA) processes. A...

  10. Subunit rotation in a single FoF1-ATP synthase in a living bacterium monitored by FRET

    Science.gov (United States)

    Seyfert, K.; Oosaka, T.; Yaginuma, H.; Ernst, S.; Noji, H.; Iino, R.; Börsch, M.

    2011-03-01

    FoF1-ATP synthase is the ubiquitous membrane-bound enzyme in mitochondria, chloroplasts and bacteria which provides the 'chemical energy currency' adenosine triphosphate (ATP) for cellular processes. In Escherichia coli ATP synthesis is driven by a proton motive force (PMF) comprising a proton concentration difference ΔpH plus an electric potential ΔΨ across the lipid membrane. Single-molecule in vitro experiments have confirmed that proton-driven subunit rotation within FoF1-ATP synthase is associated with ATP synthesis. Based on intramolecular distance measurements by single-molecule fluorescence resonance energy transfer (FRET) the kinetics of subunit rotation and the step sizes of the different rotor parts have been unraveled. However, these experiments were accomplished in the presence of a PMF consisting of a maximum ΔpH ~ 4 and an unknown ΔΨ. In contrast, in living bacteria the maximum ΔpH across the plasma membrane is likely 0.75, and ΔΨ has been measured between -80 and -140 mV. Thus the problem of in vivo catalytic turnover rates, or the in vivo rotational speed in single FoF1-ATP synthases, respectively, has to be solved. In addition, the absolute number of functional enzymes in a single bacterium required to maintain the high ATP levels has to be determined. We report our progress of measuring subunit rotation in single FoF1-ATP synthases in vitro and in vivo, which was enabled by a new labeling approach for single-molecule FRET measurements.

  11. Development of a test method for protective gloves against nanoparticles in conditions simulating occupational use

    International Nuclear Information System (INIS)

    Dolez, Patricia; Vinches, Ludwig; Vu-Khanh, Toan; Wilkinson, Kevin; Plamondon, Philippe

    2011-01-01

    Nanoparticle manufacture and use are in full expansion. The associated risks of occupational exposure raise large concerns due to their potential toxicity. Even if they stand as a last resort in the traditional occupational Health and Safety (H and S) risk management strategy, personal protective equipment (PPE) against nanoparticles are an absolute need in the context of precautionary principle advocated by H and S organizations worldwide. However no standard test method is currently available for evaluating the efficiency of PPE against nanoparticles, in particular in the case of gloves. A project is thus underway to develop a test method for measuring nanoparticle penetration through protective gloves in conditions simulating glove-nanoparticle occupational interaction. The test setup includes an exposure and a sampling chamber separated by a circular glove sample. A system of cylinders is used to deform the sample while it is exposed to nanoparticles. The whole system is enclosed in a glove box to ensure the operator safety during assembly, dismounting and clean-up operations as well as during the tests. Appropriate nanoparticle detection techniques were also identified. Results are reported here for commercial 15nm TiO2 nanoparticles - powder and colloidal solutions in 1,2-propanediol, ethylene glycol and water - and four types of protective gloves: disposable nitrile and latex as well as unsupported neoprene and butyl rubber gloves. They show that mechanical deformations and contact with colloidal solution liquid carriers may affect glove materials. Preliminary results obtained with TiO2 powder indicate a possible penetration of nanoparticles through gloves following mechanical deformations.

  12. Novel activity classification and occupancy estimation methods for intelligent HVAC (heating, ventilation and air conditioning) systems

    International Nuclear Information System (INIS)

    Rana, Rajib; Kusy, Brano; Wall, Josh; Hu, Wen

    2015-01-01

    Reductions in HVAC (heating, ventilation and air conditioning) energy consumption can be achieved by limiting heating in the winter or cooling in the summer. However, the resulting low thermal comfort of building occupants may lead to an override of the HVAC control, which revokes its original purpose. This has led to an increased interest in modeling and real-time tracking of location, activity, and thermal comfort of building occupants for HVAC energy management. While thermal comfort is well understood, it is difficult to measure in real-time environments where user context changes dynamically. Encouragingly, plethora of sensors available on smartphone unleashes the opportunity to measure user contexts in real-time. An important contextual information for measuring thermal comfort is Metabolism rate, which changes based on current physical activities. To measure physical activity, we develop an activity classifier, which achieves 10% higher accuracy compared to Support Vector Machine and k-Nearest Neighbor. Office occupancy is another contextual information for energy-efficient HVAC control. Most of the phone based occupancy estimation techniques will fail to determine occupancy when phones are left at desk while sitting or attending meetings. We propose a novel sensor fusion method to detect if a user is near the phone, which achieves more than 90% accuracy. Determining activity and occupancy our proposed algorithms can help maintaining thermal comfort while reducing HVAC energy consumptions. - Highlights: • We propose activity and occupancy detection for efficient HVAC control. • Activity classifier achieves 10% higher accuracy than SVM and kNN. • For occupancy detection we propose a novel sensor fusion method. • Using Weighted Majority Voting we fuse microphone and accelerometer data on phone. • We achieve more than 90% accuracy in detecting occupancy.

  13. Recycling of Oceanic Lithosphere: Water, fO2 and Fe-isotope Constraints

    Science.gov (United States)

    Bizmis, M.; Peslier, A. H.; McCammon, C. A.; Keshav, S.; Williams, H. M.

    2014-01-01

    Spinel peridotite and garnet pyroxenite xenoliths from Hawaii provide important clues about the composition of the oceanic lithosphere, and can be used to assess its contribution to mantle heterogeneity upon recycling. The peridotites have lower bulk H2O (approximately 70-114 ppm) than the MORB source, qualitatively consistent with melt depletion. The garnet pyroxenites (high pressure cumulates) have higher H2O (200-460 ppm, up to 550 ppm accounting for phlogopite) and low H2O/Ce ratios (less than 100). The peridotites have relatively light Fe-isotopes (delta Fe -57 = -0.34 to 0.13) that decrease with increasing depletion, while the pyroxenites are significantly heavier (delta Fe-57 up to 0.3). The observed xenolith, as well as MORB and OIB total Fe-isotope variability is larger that can be explained by existing melting models. The high H2O and low H2O/Ce ratios of pyroxenites are similar to estimates of EM-type OIB sources, while their heavy delta Fe-57 are similar to some Society and Cook-Austral basalts. Therefore, recycling of mineralogically enriched oceanic lithosphere (i.e. pyroxenites) may contribute to OIB sources and mantle heterogeneity. The Fe(3+)/Sigma? systematics of these xenoliths also suggest that there might be lateral redox gradients within the lithosphere, between juxtaposed oxidized spinel peridotites (deltaFMQ = -0.7 to 1.6, at 15 kb) and more reduced pyroxenites (deltaFMQ = -2 to -0.4, at 20-25kb). Such mineralogically and compositionally imposed fO2 gradients may generate local redox melting due to changes in fluid speciation (e.g. reduced fluids from pyroxenite encountering more oxidized peridotite). Formation of such incipient, small degree melts could further contribute to metasomatic features seen in peridotites, mantle heterogeneity, as well as the low velocity and high electrical conductivity structures near the base of the lithosphere and upper mantle.

  14. Ionospheric foF2 anomalies during some intense geomagnetic storms

    Directory of Open Access Journals (Sweden)

    R. P. Kane

    2005-10-01

    Full Text Available The global evolutions of foF2 anomalies were examined for three very intense geomagnetic storms, namely the Halloween events of October-November 2003 (Event X, 29–30 October 2003, Dst –401 nT; Event Y, 20–21 November 2003, Dst –472 nT, and the largest Dst storm (Event Z, 13–14 March 1989, Dst –589 nT. For Event X, troughs (negative storms were clearly seen for high northern and southern latitudes. For northern midlatitudes as well as for low latitudes, there were very strong positive effects on 29 October 2003, followed by negative effects the next day. For Event Y, there were no troughs in NH high latitudes for morning and evening hours but there were troughs for night. For midlatitudes and low latitudes, some longitudes showed strong negative effects in the early morning as expected, but some longitudes showed strong positive effects at noon and in the evening hours. Thus, there were many deviations from the model patterns. The deviations were erratic, indicating considerable local effects superposed on general patterns. A disconcerting feature was the presence of strong positive effects during the 24 h before the storm commencement. Such a feature appears only in the 24 h before the geomagnetic storm commencement but not earlier. If genuine, these could imply a prediction potential with a 24-h antecedence. For Event Z (13–14 March 1989, equinox, all stations (all latitudes and longitudes showed a very strong "negative storm" in the main phase, and no positive storms anywhere. Keywords. Ionosphere (Equatorial ionosphere – Ionospheric disturbances – Mid-latitude Ionosphere – Polar ionosphere

  15. Persistence of the planetary wave type oscillations in foF2 over Europe

    Directory of Open Access Journals (Sweden)

    J. Laštovička

    2003-07-01

    Full Text Available Planetary waves are oscillations of very predominantly tropospheric origin with typical periods of about 2–30 days. Their dominant zonal wave numbers are 1, 2 and 3, i.e. the waves are of large-scale (global character. The planetary wave type oscillations have been observed in the lower and middle atmosphere but also in the ionosphere, including the ionospheric F2-layer. Here, we deal only with the oscillations analyzed for four European stations over a solar cycle with the use of the Meyer and Morlet wavelet transforms. Waves with periods near 5, 10 and 16 days are studied. Only events with a duration of three wave-cycles and more are considered. The 5-day period wave events display a typical duration of 4 cycles, while 10- and 16-day wave events are less persistent, with a typical duration of about 3.5 cycles and 3 cycles, respectively. The persistence pattern in terms of number of cycles and in terms of number of days is different. In terms of number of cycles, the typical persistence of oscillations decreases with increasing period. On the other hand, in terms of number of days the typical persistence evidently increases with increasing period. The spectral distribution of event duration is too broad to allow for a reasonable prediction of event duration. Thus, the predictability of the planetary wave type oscillations in foF2 seems to be very questionable.Key words. Ionosphere (ionosphere-atmosphere interaction, mid-latitude ionosphere, ionospheric disturbances – Meteorology and atmospheric dynamics (waves and tides

  16. Persistence of the planetary wave type oscillations in foF2 over Europe

    Directory of Open Access Journals (Sweden)

    D. Novotná

    Full Text Available Planetary waves are oscillations of very predominantly tropospheric origin with typical periods of about 2–30 days. Their dominant zonal wave numbers are 1, 2 and 3, i.e. the waves are of large-scale (global character. The planetary wave type oscillations have been observed in the lower and middle atmosphere but also in the ionosphere, including the ionospheric F2-layer. Here, we deal only with the oscillations analyzed for four European stations over a solar cycle with the use of the Meyer and Morlet wavelet transforms. Waves with periods near 5, 10 and 16 days are studied. Only events with a duration of three wave-cycles and more are considered. The 5-day period wave events display a typical duration of 4 cycles, while 10- and 16-day wave events are less persistent, with a typical duration of about 3.5 cycles and 3 cycles, respectively. The persistence pattern in terms of number of cycles and in terms of number of days is different. In terms of number of cycles, the typical persistence of oscillations decreases with increasing period. On the other hand, in terms of number of days the typical persistence evidently increases with increasing period. The spectral distribution of event duration is too broad to allow for a reasonable prediction of event duration. Thus, the predictability of the planetary wave type oscillations in foF2 seems to be very questionable.Key words. Ionosphere (ionosphere-atmosphere interaction, mid-latitude ionosphere, ionospheric disturbances – Meteorology and atmospheric dynamics (waves and tides

  17. Methods of optimization of reactive sputtering conditions of Al target during AlN films deposition

    Directory of Open Access Journals (Sweden)

    Chodun Rafal

    2015-12-01

    Full Text Available Encouraged by recent studies and considering the well-documented problems occurring during AlN synthesis, we have chosen two diagnostic methods which would enable us to fully control the process of synthesis and characterize the synthesized aluminum nitride films. In our experiment we have compared the results coming from OES measurements of plasma and circulating power characteristics of the power supply with basic features of the deposited layers. The dual magnetron system operating in AC mode was used in our studies. Processes of aluminum target sputtering were carried out in an atmosphere of a mixture of argon and nitrogen. The plasma emission spectra were measured with the use of a monochromator device. Analyses were made by comparing the positions and intensities of spectral lines of the plasma components. The results obtained allowed us to characterize the sputtering process under various conditions of gas mixture compositions as well as power distribution more precisely, which is reported in this work. The measured spectra were related to the deposition rate, the structure morphology of the films and chemical composition. Our work proved that the use of plasma OES and circulating power measurements make possible to control the process of sputtering and synthesis of deposited films in situ.

  18. Mixed convection in inclined lid driven cavity by Lattice Boltzmann Method and heat flux boundary condition

    International Nuclear Information System (INIS)

    D'Orazio, A; Karimipour, A; Nezhad, A H; Shirani, E

    2014-01-01

    Laminar mixed convective heat transfer in two-dimensional rectangular inclined driven cavity is studied numerically by means of a double population thermal Lattice Boltzmann method. Through the top moving lid the heat flux enters the cavity whereas it leaves the system through the bottom wall; side walls are adiabatic. The counter-slip internal energy density boundary condition, able to simulate an imposed non zero heat flux at the wall, is applied, in order to demonstrate that it can be effectively used to simulate heat transfer phenomena also in case of moving walls. Results are analyzed over a range of the Richardson numbers and tilting angles of the enclosure, encompassing the dominating forced convection, mixed convection, and dominating natural convection flow regimes. As expected, heat transfer rate increases as increases the inclination angle, but this effect is significant for higher Richardson numbers, when buoyancy forces dominate the problem; for horizontal cavity, average Nusselt number decreases with the increase of Richardson number because of the stratified field configuration

  19. Method and apparatus for scientific analysis under low temperature vacuum conditions

    Science.gov (United States)

    Winefordner, James D.; Jones, Bradley T.

    1990-01-01

    A method and apparatus for scientific analysis of a sample under low temperature vacuum conditions uses a vacuum chamber with a conveyor belt disposed therein. One end of the conveyor belt is a cool end in thermal contact with the cold stage of a refrigerator, whereas the other end of the conveyor belt is a warm end spaced from the refrigerator. A septum allows injection of a sample into the vacuum chamber on top of the conveyor belt for spectroscopic or other analysis. The sample freezes on the conveyor belt at the cold end. One or more windows in the vacuum chamber housing allow spectroscopic analysis of the sample. Following the spectroscopic analysis, the conveyor belt may be moved such that the sample moves toward the warm end of the conveyor belt where upon it evaporates, thereby cleaning the conveyor belt. Instead of injecting the sample by way of a septum and use of a syringe and needle, the present device may be used in series with capillary-column gas chromatography or micro-bore high performance liquid chromatography.

  20. Comparison of methods for calculating conditional expectations of sufficient statistics for continuous time Markov chains

    Directory of Open Access Journals (Sweden)

    Tataru Paula

    2011-12-01

    Full Text Available Abstract Background Continuous time Markov chains (CTMCs is a widely used model for describing the evolution of DNA sequences on the nucleotide, amino acid or codon level. The sufficient statistics for CTMCs are the time spent in a state and the number of changes between any two states. In applications past evolutionary events (exact times and types of changes are unaccessible and the past must be inferred from DNA sequence data observed in the present. Results We describe and implement three algorithms for computing linear combinations of expected values of the sufficient statistics, conditioned on the end-points of the chain, and compare their performance with respect to accuracy and running time. The first algorithm is based on an eigenvalue decomposition of the rate matrix (EVD, the second on uniformization (UNI, and the third on integrals of matrix exponentials (EXPM. The implementation in R of the algorithms is available at http://www.birc.au.dk/~paula/. Conclusions We use two different models to analyze the accuracy and eight experiments to investigate the speed of the three algorithms. We find that they have similar accuracy and that EXPM is the slowest method. Furthermore we find that UNI is usually faster than EVD.

  1. An illustration of new methods in machine condition monitoring, Part I: stochastic resonance

    International Nuclear Information System (INIS)

    Worden, K.; Antoniadou, I.; Marchesiello, S.; Mba, C.; Garibaldi, L.

    2017-01-01

    There have been many recent developments in the application of data-based methods to machine condition monitoring. A powerful methodology based on machine learning has emerged, where diagnostics are based on a two-step procedure: extraction of damage-sensitive features, followed by unsupervised learning (novelty detection) or supervised learning (classification). The objective of the current pair of papers is simply to illustrate one state-of-the-art procedure for each step, using synthetic data representative of reality in terms of size and complexity. The first paper in the pair will deal with feature extraction. Although some papers have appeared in the recent past considering stochastic resonance as a means of amplifying damage information in signals, they have largely relied on ad hoc specifications of the resonator used. In contrast, the current paper will adopt a principled optimisation-based approach to the resonator design. The paper will also show that a discrete dynamical system can provide all the benefits of a continuous system, but also provide a considerable speed-up in terms of simulation time in order to facilitate the optimisation approach. (paper)

  2. An Illustration of New Methods in Machine Condition Monitoring, Part II: Adaptive outlier detection

    Science.gov (United States)

    Antoniadou, I.; Worden, K.; Marchesiello, S.; Mba, C.; Garibaldi, L.

    2017-05-01

    There have been many recent developments in the application of data-based methods to machine condition monitoring. A powerful methodology based on machine learning has emerged, where diagnostics are based on a two-step procedure: extraction of damage-sensitive features, followed by unsupervised learning (novelty detection) or supervised learning (classification). The objective of the current pair of papers is simply to illustrate one state-of-the-art procedure for each step, using synthetic data representative of reality in terms of size and complexity. The second paper in the pair will deal with novelty detection. Although there has been considerable progress in the use of outlier analysis for novelty detection, most of the papers produced so far have suffered from the fact that simple algorithms break down if multiple outliers are present or if damage is already present in a training set. The objective of the current paper is to illustrate the use of phase-space thresholding; an algorithm which has the ability to detect multiple outliers inclusively in a data set.

  3. An illustration of new methods in machine condition monitoring, Part I: stochastic resonance

    Science.gov (United States)

    Worden, K.; Antoniadou, I.; Marchesiello, S.; Mba, C.; Garibaldi, L.

    2017-05-01

    There have been many recent developments in the application of data-based methods to machine condition monitoring. A powerful methodology based on machine learning has emerged, where diagnostics are based on a two-step procedure: extraction of damage-sensitive features, followed by unsupervised learning (novelty detection) or supervised learning (classification). The objective of the current pair of papers is simply to illustrate one state-of-the-art procedure for each step, using synthetic data representative of reality in terms of size and complexity. The first paper in the pair will deal with feature extraction. Although some papers have appeared in the recent past considering stochastic resonance as a means of amplifying damage information in signals, they have largely relied on ad hoc specifications of the resonator used. In contrast, the current paper will adopt a principled optimisation-based approach to the resonator design. The paper will also show that a discrete dynamical system can provide all the benefits of a continuous system, but also provide a considerable speed-up in terms of simulation time in order to facilitate the optimisation approach.

  4. Extensible Stylesheet Language Formatting Objects (XSL-FO): a tool to transform patient data into attractive clinical reports.

    Science.gov (United States)

    Simonaitis, Linas; Belsito, Anne; Warvel, Jeff; Hui, Siu; McDonald, Clement J

    2006-01-01

    Clinicians at Wishard Hospital in Indianapolis print and carry clinical reports called "Pocket Rounds". This paper describes a new process we developed to improve these clinical reports. The heart of our new process is a World Wide Web Consortium standard: Extensible Stylesheet Language Formatting Objects (XSL-FO). Using XSL-FO stylesheets we generated Portable Document Format (PDF) and PostScript reports with complex formatting: columns, tables, borders, shading, indents, dividing lines. We observed patterns of clinical report printing during a eight month study period on three Medicine wards. Usage statistics indicated that clinicians accepted the new system enthusiastically: 78% of 26,418 reports were printed using the new system. We surveyed 67 clinical users. Respondents gave the new reports a rating of 4.2 (on a 5 point scale); they gave the old reports a rating of 3.4. The primary complaint was that it took longer to print the new reports. We believe that XSL-FO is a promising way to transform text data into functional and attractive clinical reports: relatively easy to implement and modify.

  5. Similarity and conditional similarity reductions of a (2+1)-dimensional KdV equation via a direct method

    Science.gov (United States)

    Lou, Sen-yue; Tang, Xiao-yan; Lin, Ji

    2000-12-01

    To get the similarity solutions of a nonlinear physical equation, one may use the classical Lie group approach, nonclassical Lie group approach and the Clarkson and Kruskal (CK) direct method. In this paper the direct method is modified to get the similarity and conditional similarity reductions of a (2+1) dimensional KdV-type equation. Ten types of usual similarity reductions [including the (1+1)-dimensional shallow water wave equation and the variable KdV equation] and six types of conditional similarity reductions of the (2+1)-dimensional KdV equation are obtained. Some special solutions of the conditional similarity reduction equations are found to show the nontriviality of the conditional similarity reduction approach. The conditional similarity solutions cannot be obtained by using the nonclassical Lie group approach in its present form. How to modify the nonclassical Lie group approach to obtain the conditional similarity solutions is still open.

  6. Involving the Navier-Stokes equations in the derivation of boundary conditions for the lattice Boltzmann method.

    Science.gov (United States)

    Verschaeve, Joris C G

    2011-06-13

    By means of the continuity equation of the incompressible Navier-Stokes equations, additional physical arguments for the derivation of a formulation of the no-slip boundary condition for the lattice Boltzmann method for straight walls at rest are obtained. This leads to a boundary condition that is second-order accurate with respect to the grid spacing and conserves mass. In addition, the boundary condition is stable for relaxation frequencies close to two.

  7. Solution of Two-dimensional Parabolic Equation Subject to Non-local Boundary Conditions Using Homotopy Perturbation Method

    Directory of Open Access Journals (Sweden)

    Puskar Raj SHARMA

    2012-01-01

    Full Text Available Aim of the paper is to investigate solution of twodimensional linear parabolic partial differential equation with non-local boundary conditions using Homotopy Perturbation Method (HPM. This method is not only reliable in obtaining solution of such problems in series form with high accuracy but it also guarantees considerable saving of the calculation volume and time as compared to other methods. The application of the method has been illustrated through an example

  8. Condition monitoring approach for permanent magnet synchronous motor drives based on the INFORM method

    OpenAIRE

    Arellano-Padilla, J.; Sumner, M.; Gerada, C.

    2016-01-01

    This paper proposes a monitoring scheme based on saliency tracking to assess the health condition of PMSM drives operating under non stationary conditions. The evaluated scheme is based on the INFORM methodology, which is associated to the accurate sensorless control of PM drives without zero speed limitation. The result is a monitoring scheme that is able to detect faults that would be very difficult to evaluate under nonstationary conditions. A relevant aspect of the proposed scheme is that...

  9. Novel Methods for Optically Measuring Whitecaps Under Natural Wave Breaking Conditions in the Southern Ocean

    Science.gov (United States)

    Randolph, K. L.; Dierssen, H. M.; Cifuentes-Lorenzen, A.; Balch, W. M.; Monahan, E. C.; Zappa, C. J.; Drapeau, D.; Bowler, B.

    2016-02-01

    Breaking waves on the ocean surface mark areas of significant importance to air-sea flux estimates of gas, aerosols, and heat. Traditional methods of measuring whitecap coverage using digital photography can miss features that are small in size or do not show high enough contrast to the background. The geometry of the images collected captures the near surface, bright manifestations of the whitecap feature and miss a portion of the bubble plume that is responsible for the production of sea salt aerosols and the transfer of lower solubility gases. Here, a novel method for accurately measuring both the fractional coverage of whitecaps and the intensity and decay rate of whitecap events using above water radiometry is presented. The methodology was developed using data collected during the austral summer in the Atlantic sector of the Southern Ocean under a large range of wind (speeds of 1 to 15 m s-1) and wave (significant wave heights 2 to 8 m) conditions as part of the Southern Ocean Gas Exchange experiment. Whitecap metrics were retrieved by employing a magnitude threshold based on the interquartile range of the radiance or reflectance signal for a single channel (411 nm) after a baseline removal, determined using a moving minimum/maximum filter. Breaking intensity and decay rate metrics were produced from the integration of, and the exponential fit to, radiance or reflectance over the lifetime of the whitecap. When compared to fractional whitecap coverage measurements obtained from high resolution digital images, radiometric estimates were consistently higher because they capture more of the decaying bubble plume area that is difficult to detect with photography. Radiometrically-retrieved whitecap measurements are presented in the context of concurrently measured meteorological (e.g., wind speed) and oceanographic (e.g., wave) data. The optimal fit of the radiometrically estimated whitecap coverage to the instantaneous wind speed, determined using ordinary least

  10. Runaway reactions, their courses and the methods to establish safe process conditions

    Science.gov (United States)

    Gustin, J. L.

    1991-08-01

    to fire or external heating. Considering the various runaway situations, the effectiveness of the following approaches is discussed: - Theoretical and experimental information required for hazard assessment. - Choice of adequate process conditions. - Choice of adequate methods for process control. - Experimental information required for vent sizing. La plus grande partie de la littérature sur les emballements thermiques traite des conséquences de l'accident telles que les effets mécaniques, les émissions toxiques et inflammables. Les travaux publiés par le DIERS fournissent des méthodes permettant le dimensionnement d'évents, nécessitant des déterminations expérimentales. Il y a moins d'information sur la manière dont les emballements thermiques peuvent survenir alors que ceux-ci peuvent avoir différentes causes. Le propos de cet article est de décrire les différentes dérives de procédé qui peuvent entraîner un emballement thermique et de déterminer l'information expérimentale nécessaire pour l'analyse des risques du procédé, le choix de conditions opératoires sûres et la réduction des conséquences de l'emballement thermique. Chaque dérive de procédé dangereuse, est illustrée par des exemples connus dans l'industrie chimique et par des données expérimentales obtenues dans des essais de laboratoire. Les conditions de procédé dangereuses prises en compte sont les suivantes: 1)L'emballement thermique homogène dû à une température excessive; 2) L'emballement thermique homogène par introduction d'un catalyseur ou d'un réactif contrôlant; 3) L'emballement thermique hétérogène dû à une température locale excessive; 4)L'emballement thermique hétérogène dû à une faible conduction thermique vers l'extérieur; 5) L'emballement thermique dû à un temps de séjour excessif à la température du procédé (Réactions autocatalytiques); 6) L'emballement thermique par accumulation de réactifs. La vitesse d'introduction d'un r

  11. Laboratory test methods to determine the degradation of plastics in marine environmental conditions

    Directory of Open Access Journals (Sweden)

    Maurizio eTosin

    2012-06-01

    Full Text Available In this technology report, three test methods were developed to characterize the degradation of plastic in marine environment. The aim was to outline a test methodology to measure the physical and biological degradation in different habitats where plastic waste can deposit when littered in the sea. Previously, research has focused mainly on the conditions encountered by plastic items when floating in the sea water (pelagic domain. However, this is just one of the possible habitats that plastic waste can be exposed to. Waves and tides tend to wash up plastic waste on the shoreline, which is also a relevant habitat to be studied. Therefore, the degradation of plastic items buried under sand kept wet with sea water has been followed by verifying the disintegration (visual disappearing as a simulation of the tidal zone. Most biodegradable plastics have higher densities than water and also as a consequence of fouling, they tend to sink and lay on the sea floor. Therefore, the fate of plastic items lying on the sediment has been followed by monitoring the oxygen consumption (biodegradation. Also the effect of a prolonged exposure to the sea water, to simulate the pelagic domain, has been tested by measuring the decay of mechanical properties. The test material (Mater-Bi was shown to degrade (total disintegration achieved in less than 9 months when buried in wet sand (simulation test of the tidal zone, to lose mechanical properties but still maintain integrity (tensile strength at break = -66% in 2 years when exposed to sea water in an aquarium (simulation of pelagic domain, and substantially biodegrade (69% in 236 days; biodegradation relative to paper: 88% when located at the sediment/sea water interface (simulation of benthic domain. This study is not conclusive as the methodological approach must be completed by also determining degradation occurring in the supralittoral zone, on the deep sea floor, and in the anoxic sediment.

  12. Localization value of seizure semiology analyzed by the conditional inference tree method.

    Science.gov (United States)

    Kim, Dong Wook; Jung, Ki-Young; Chu, Kon; Park, So-Hee; Lee, Seo-Young; Lee, Sang Kun

    2015-09-01

    Although accurate interpretation of seizures is important for the management of patients with epilepsy, studies on the localizing value of seizure semiology and the reliability of the semiology descriptions are scarce. The objective of our study is to investigate the accuracy of video-recorded seizure semiology in the classification and localization of epileptic seizures. We also evaluated the reliability of the semiology descriptions provided by the patients or their caregivers. Video-recorded clinical seizures from 831 consecutive patients (391 females; 31.7 ± 11.6 years) were analyzed retrospectively. Epileptic seizures were classified as generalized and partial seizures, and patients with partial seizures were further divided into five ictal onset areas. In order to analyze the diagnostic value of individual semiologic features for clinical diagnosis, we used the conditional inference tree method. Generalized and partial seizures were differentiated with high accuracy (97.1%), but the accuracy of localization among the five ictal onset areas was relatively low (56.1%), which was largely attributed to the difficulty in the discrimination between mesial and lateral temporal onset seizures. Lateralization of the ictal onset area in partial seizures was possible in 427 (55.1%) patients based on video analysis, nevertheless it was possible in only 158 (20.4%) patients based on historical semiology descriptions. The results of our study suggest that careful observation of seizure semiology may be useful for the differentiation of ictal onset areas. However, the semiologic differentiation between mesial and lateral temporal onset seizures is difficult, and historical semiologic descriptions should be interpreted carefully because of their low reliability. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. An Alternative Teaching Method of Conditional Probabilities and Bayes' Rule: An Application of the Truth Table

    Science.gov (United States)

    Satake, Eiki; Vashlishan Murray, Amy

    2015-01-01

    This paper presents a comparison of three approaches to the teaching of probability to demonstrate how the truth table of elementary mathematical logic can be used to teach the calculations of conditional probabilities. Students are typically introduced to the topic of conditional probabilities--especially the ones that involve Bayes' rule--with…

  14. 40 CFR 86.166-12 - Method for calculating emissions due to air conditioning leakage.

    Science.gov (United States)

    2010-07-01

    ... rate for the compressors in the air conditioning system, in grams per year. OHS = The number of O-ring... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY...). (a) Emission totals. Calculate an annual rate of refrigerant leakage from an air conditioning system...

  15. Compositions and methods for providing plants with tolerance to abiotic stress conditions

    KAUST Repository

    Hirt, Heribert

    2017-07-27

    It has been discovered that the desert endophytic bacterium SA187 SA187 can provide resistance or tolerance to abiotic stress conditions to seeds or plants. Compositions containing SA187 can be used to enhance plant development and yield under environmental stress conditions.

  16. Conditions Affecting the Accuracy of Classical Equating Methods for Small Samples under the NEAT Design: A Simulation Study

    Science.gov (United States)

    Sunnassee, Devdass

    2011-01-01

    Small sample equating remains a largely unexplored area of research. This study attempts to fill in some of the research gaps via a large-scale, IRT-based simulation study that evaluates the performance of seven small-sample equating methods under various test characteristic and sampling conditions. The equating methods considered are typically…

  17. Vocal Ergonomics in the Workplace: Heating, Ventilation, and Air-Conditioning Method Influences on Vocal Comfort and Function

    Science.gov (United States)

    Sandage, Mary J.; Rahn, Keith A.; Smith, Audrey G.

    2017-01-01

    Purpose: The purpose of this study was to examine the influence of the heating, ventilation, and air-conditioning method on voice function following a voicing task using ecologically valid offices, one with radiant HVAC and one with forced air. Method: A total of 12 consented participants (6 women, 6 men) narrated a video in each of 4…

  18. A Comparison of Three Methods for Computing Scale Score Conditional Standard Errors of Measurement. ACT Research Report Series, 2013 (7)

    Science.gov (United States)

    Woodruff, David; Traynor, Anne; Cui, Zhongmin; Fang, Yu

    2013-01-01

    Professional standards for educational testing recommend that both the overall standard error of measurement and the conditional standard error of measurement (CSEM) be computed on the score scale used to report scores to examinees. Several methods have been developed to compute scale score CSEMs. This paper compares three methods, based on…

  19. An Innovative Mixed Methods Approach to Studying the Online Health Information Seeking Experiences of Adults with Chronic Health Conditions

    Science.gov (United States)

    Mayoh, Joanne; Bond, Carol S.; Todres, Les

    2012-01-01

    This article presents an innovative sequential mixed methods approach to researching the experiences of U.K. adults with chronic health conditions seeking health information online. The use of multiple methods integrated within a single study ensured that the focus of the research was emergent and relevant and ultimately provided a more complete…

  20. Electrostatic Accelerometer for the Gravity Recovery and Climate Experiment Follow-On Mission (GRACE FO)

    Science.gov (United States)

    Perrot, Eddy; Boulanger, Damien; Christophe, Bruno; Foulon, Bernard; Liorzou, Françoise; Lebat, Vincent

    2014-05-01

    The GRACE FO mission, led by the JPL (Jet Propulsion Laboratory), is an Earth-orbiting gravity mission, continuation of the GRACE mission, that will produce an accurate model of the Earth's gravity field variation providing global climatic data during five year at least. The mission involves two satellites in a loosely controlled tandem formation, with a micro-wave link, and optionally a laser link, measuring the inter-satellites distance variation. Non-uniformities in the distribution of the Earth's mass cause the distance between the two satellites to vary. This variation is measured to recover gravity, after subtracting the non-gravitational contributors, as the residual drag. ONERA (the French Aerospace Lab) is developing, manufacturing and testing electrostatic accelerometers measuring this residual drag applied on the satellites. The accelerometer is composed of two main parts: the Sensor Unit (including the Sensor Unit Mechanics - SUM - and the Front-End Electronic Unit - FEEU) and the Interface Control Unit. In the Accelerometer Core, located in the Sensor Unit Mechanics, the proof mass is levitated and maintained in a center of an electrode cage by electrostatic forces. Thus, any drag acceleration applied on the satellite involves a variation on the servo-controlled electrostatic suspension of the mass. The voltage on the electrodes providing this electrostatic force is the measurement output of the accelerometer. The Preliminary Design Review was achieved successfully on November 2013. The FEEU Engineering Model is under test. Preliminary results on electronic unit will be compared with the expected performance. The integration of the SUM Engineering Model and the first ground levitation of the proof-mass will be presented. The impact of the accelerometer defaults (geometry, electronic and parasitic forces) leads to bias, misalignment and scale factor error, non-linearity and noise. Some of these accelerometer defaults are characterized by tests with

  1. Space-dependent core/reflector boundary conditions generated by the boundary element method for pressurized water reactors

    International Nuclear Information System (INIS)

    Itagaki, M.; Brebbia, C.A.

    1991-01-01

    This paper reports on the boundary element method used to generate energy-dependent matrix-type boundary conditions along core/reflector interfaces and along baffle-plate surfaces of pressurized water reactors. This method enables one to deal with all types of boundary geometries including convex and concave corners. The method is applicable to neutron diffusion problems with more than two energy groups and also can be used to model a reflector with or without a baffle plate. Excellent eigenvalue and flux shape results can be obtained when the boundary conditions generated by this technique are coupled with core-only finite difference calculations

  2. Development of technology for the in-service inspection of reactor pressure vessel metal condition using a magnetic method

    International Nuclear Information System (INIS)

    Bakirov, M. B.; Zabruskov, N.Y; Massoud, J.P.

    2002-01-01

    The opportunity to perform the inspection of condition of base metal and metal of welded joints of cladded vessels of PWR by non destructive methods is shown. The technique for on-site specimen-free testing is offered on the basis of sharing a kinetic hardness method and magnetic method. The results of studies of magnetic and mechanical properties of vessel steels in various condition after irradiation and thermal processing are submitted. It is shown, that the magnetic properties (first of all coercive force) are sensitive to change of structure of a material. (authors)

  3. 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.

  4. Effects of processing methods and commercial storage conditions on the extra virgin olive oil quality indexes

    Directory of Open Access Journals (Sweden)

    Kiritsakis, A.

    2007-09-01

    Full Text Available The effect of machinery groups, packing materials and light intensities was ascertained on indices of oxidative deterioration, peroxide value, and extinction coefficient K232 and K270 of extra virgin olive oil for one season of olive harvesting in an effort to simulate commercial storage conditions. It was revealed that during the storage of olive oil the peroxide value was significantly affected by the type of extraction machinery, packing material and light intensity. It is significant that oil exposed to diffused daylight and artificial light attained maximum PV in the second or third month of storage and de creased thereafter, while samples stored in the dark attained their maximum PV during the sixth month of storage. Oil samples extracted using the centrifugal type of machines and kept in glass containers in the dark had higher peroxide values than those extracted by the classic method. The rate of changes of the PV and the two indices K232 and K270 was also affected similarly by the type of machinery, packing material and light intensity.El efecto de la maquinaria, el material de envasado y la intensidad de luz fue relacionado con los índices de deterioración oxidativa, índice de peróxidos (IP y coeficientes de extinción K232 y K270 del aceite de oliva virgen extra durante una campaña de cosecha de aceituna en un esfuerzo por simular las condiciones de almacenamiento comercial. Esto reveló que durante el almacenamiento del aceite de oliva el índice de peróxidos fue afectado significativamente por el tipo de maquinaria de extracción, el material de envasado y la intensidad de luz. Es significativo que el aceite expuesto a la luz diaria difusa y a la artificial alcanzara el máximo IP en el segundo o tercer mes de almacenamiento, decreciendo a partir de este momento, mientras que las muestras almacenadas en oscuridad no alcanzaban su máximo IP hasta el sexto mes de conservación. Las muestras de aceite extraídas con centr

  5. Magnetite nanoparticles prepared by co-precipitation method in different conditions

    Energy Technology Data Exchange (ETDEWEB)

    Aphesteguy, J.C., E-mail: caphestegu@fi.uba.ar [LAFMACEL-INTECIN, Facultad de Ingeniería, UBA, Paseo Colón 850, C1063EHA Buenos Aires (Argentina); Kurlyandskaya, G.V. [Universidad del País Vasco UPV-EHU, Dept. Electricidad y Electronica, 48940 Leioa (Spain); Ural Federal University, Dept. Magnetism and Magnetic Nanomaterials, 620000 Ekaterinburg (Russian Federation); Celis, J.P. de [National Technology University (UTN), Facultad Regional Avellaneda, Department of Chemistry (Argentina); Safronov, A.P. [Ural Federal University, Dept. Magnetism and Magnetic Nanomaterials, 620000 Ekaterinburg (Russian Federation); Institute of Electrophysics UD RAS, Ekaterinburg 620016 (Russian Federation); Schegoleva, N.N. [Institute of Metal Physics UD RAS, Ekaterinburg 620044 (Russian Federation)

    2015-07-01

    Magnetic nanoparticles (MNPs) of pure magnetite (Fe{sub 3}O{sub 4}) were prepared in an aqueous solution (sample M−I) and in a water-ethyl alcohol mixture (sample M−II) by the co-precipitation method. The structure and magnetic properties of both samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), magnetic (M−H) and microwave measurements (FMR). The mean average particle diameter and particle size distribution was evaluated by the Dynamic Light Scattering (DLS) and Brunauer- Emmett-Teller techniques (BET). The Quantitative chemical analysis of iron was performed by Inductively Coupled Plasma (ICP)- Atomic Emission Spectroscopy (AES) technique. The MNPs prepared in aqueous solution show a higher grain than those prepared in the water-ethyl alcohol mixture. The type of phase structure in both cases can be defined as “defective spinel”. The shape of the majority of M−I MNPs is octahedral. The shape of the majority of M−II MNPs is cubic. The specific surface area of MNPs was as high as 14.4 m{sup 2}/g for M−I sample and 77.8 m{sup 2}/g for sample M–II. The obtained saturation magnetization values of 75 emu/g (M−I) and 68 emu/g (M−II) are consistent with expected values for magnetite MNPs of observed sizes. Ferromagnetic resonance (FMR) measurements confirmed that MNPs of both types are magnetically homogeneous materials. FMR lines' position and line widths can be understood by invoking the local dipolar fields, deviations from sphericity, magnetocrystalline anisotropy and stresses. M−I sample shows sizeable zero field microwave absorption which is absent in the M−II case. The differences in microwave behaviour of M−I and M−II MNPs can be used in the design of microwave radiation absorbing multilayers. - Highlights: • Magnetite nanoparticles were prepared in two different conditions. • Specific surface area of sample prepared in water- ethanol mix is

  6. Cristae architecture is determined by an interplay of the MICOS complex and the F1FO ATP synthase via Mic27 and Mic10

    Directory of Open Access Journals (Sweden)

    Katharina Eydt

    2017-07-01

    Full Text Available The inner boundary and the cristae membrane are connected by pore-like structures termed crista junctions (CJs. The MICOS complex is required for CJ formation and enriched at CJs. Here, we address the roles of the MICOS subunits Mic27 and Mic10. We observe a positive genetic interaction be-tween Mic27 and Mic60 and deletion of Mic27 results in impaired formation of CJs and altered cristae membrane curvature. Mic27 acts in an antagonistic manner to Mic60 as it promotes oligomerization of the F1FO-ATP synthase and partially restores CJ formation in cells lacking Mic60. Mic10 impairs oli-gomerization of the F1FO-ATP synthase similar to Mic60. Applying complex-ome profiling, we observed that deletion of Mic27 destabilizes the MICOS complex but does not impair formation of a high molecular weight Mic10 subcomplex. Moreover, this Mic10 subcomplex comigrates with the dimeric F1FO-ATP synthase in a Mic27-independent manner. Further, we observed a chemical crosslink of Mic10 to Mic27 and of Mic10 to the F1FO-ATP synthase subunit e. We corroborate the physical interaction of the MICOS complex and the F1FO-ATP synthase. We propose a model in which part of the F1FO-ATP synthase is linked to the MICOS complex via Mic10 and Mic27 and by that is regulating CJ formation.

  7. Upper and lower solutions method for differential inclusions with integral boundary conditions

    Directory of Open Access Journals (Sweden)

    Abdelghani Ouahab

    2006-03-01

    Full Text Available A nonlinear alternative of the Leray-Schauder type for multivalued maps combined with upper and lower solutions is used to investigate the existence of solutions for second-order differential inclusions with integral boundary conditions.

  8. Methods of monitoring the technical condition of the braking system of an autonomous vehicle during operation

    Science.gov (United States)

    Revin, A.; Dygalo, V.; Boyko, G.; Lyaschenko, M.; Dygalo, L.

    2018-02-01

    Possibilities of diagnosing of a technical condition of braking system of the autonomous vehicles with automated modules while in service are considered. The concept of sharing of onboard means and stands for diagnosing is presented.

  9. A comparison of five methods for assessing veld condition in the ...

    African Journals Online (AJOL)

    They key species method has the advantage of simplicity and speed, and should stimulate farmers to undertake routine monitoring of their veld in these two regions. Keywords: Benchmark method; botany; detrended correspondence analysis; grassveld; Grazing capacity; highland sourveld; key species; Key species method ...

  10. Methods for reducing lipid oxidation in fish-oil-enriched energy bars

    DEFF Research Database (Denmark)

    Nielsen, Nina Skall; Jacobsen, Charlotte

    2009-01-01

    similar protection towards oxidation as packaging the energy bars in modified atmosphere. These protection methods were although not as efficient as addition of FO as micro-encapsulated powder. Addition of the metal chelator ethylene diamine tetra-acetic acid (EDTA) (100-2000 ppm) to emulsified FO...

  11. Development of methods for treatment and conditioning of biological radioactive waste in the Czech Republic

    International Nuclear Information System (INIS)

    Holub, J.

    1997-01-01

    Incineration of biological radioactive waste was performed in a facility manufactured in the Czech Republic for combustion of burnable, radioactive and non-radioactive residues. The equipment has shown an adequate capability for combustion of biological waste. Basic technical parameters of the incinerator SP-603 can guarantee combustion of majority of wastes from different radionuclide users in the country. To ensure proper further handling with the resulting ash, three conditioning options were studied, the bituminization process, incorporation into cement, and embedding of ash into a mixture of bituminous and cementitious materials. Mechanical properties of the conditioned ash were in good compliance with those published elsewhere. Bituminized ash exhibits lowest leachibility, followed by the ash conditioned by means of the mixed process. Potential abnormal operation conditions were evaluated and their consequences assessed. The evaluation encompassed sensitivity analysis of the consequences potentially affecting the operating staff, nearby population and the environment. Cost estimate was carried out using a national approach for the calculation. From the results it can be seen that there are no large differences between the conditioning and disposal of wastes resulting from different conditioning processes. (author). 16 refs, 4 figs, 15 tabs

  12. Time dependent quantum study of the H(S)+FO(2II)→OH(2II)+F(2P) reaction

    International Nuclear Information System (INIS)

    Tutuk, R.; Karabulut, E.; Kurban, M.; Goektas, F.

    2010-01-01

    The dynamics of the H( 2 S)+FO( 2 II)→OH ( 2 II) +F( 2 P) reaction on the adiabatic potential energy surface of the ground 3A' state is investigated by using the quantum mechanical real wave packet method . Time dependent Schroedinger equation was solved by means of the Real wave packet method of Gray and Balint-Kurti. The asymptotic wave packet was analysed by Fourier Grid method and the state-to-state and state-to-all reaction probabilities were calculated at zero total angular momentum quantum number. Capture model was used to calculate the total reaction probabilities for J > 0 and the integral cross sections were calculated by summing the total reaction probabilities over the all J values. The initial state selected thermal rate constants were calculated by Boltzmann averaging of the integral cross sections over all energies. The state-to-state reaction probabilities and partial differential cross sections do not show any resonance structure. Both partial differential and integral cross sections show threshold behaviour as expected and the reaction rate constant presents a clear temperature dependency.

  13. Organizational methods conditions of formation of motivation at corresponding pedagogical skills to professional-applied physical training

    Directory of Open Access Journals (Sweden)

    Victorya Tsybul’ska

    2014-12-01

    Full Text Available Purpose: to develop organizational and methodological conditions of formation and motivation of students to determine their effectiveness. Materials and Methods: the study was conducted by third year student of the correspondence department of the Faculty of Primary Education (53 people. We used the following methods: survey of theoretical knowledge, motor tests, evaluation methods of physical health (G. Apanasenko, psychological methods of training motivation (T. Ilyina, motivation to succeed (T. Elers, rapid diagnosis empathy (I. Yusupova, methods of mathematical statistics. Results: the factors that affect the state of professionally-applied physical fitness of students of the correspondence department of the Faculty of Primary Education. Conclusions: the proposed organizational and methodological conditions activation independent of external students is the basis for providing in centives for self-study educational materials, improving theoretical knowledge in the field of physical education, increased motor activity through various forms of regular exercise.

  14. A method for calorimetric analysis in variable conditions heating; Methode d'analyse calorimetrique en regime variable

    Energy Technology Data Exchange (ETDEWEB)

    Berthier, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    By the analysis of the thermal transition conditions given by the quenching of a sample in a furnace maintained at a high temperature, it is possible to study the thermal diffusivity of some materials and those of solid state structure transformation on a qualitative as well as a quantitative standpoint. For instance the transformation energy of {alpha}-quartz into {beta}-quartz and the Wigner energy stored within neutron-irradiated beryllium oxide have been measured. (author) [French] L'analyse du regime thermique transitoire, obtenu par la trempe d'un echantillon dans l'enceinte d'un four maintenu a tres haute temperature, peut permettre l'etude de la diffusivite thermique de certains materiaux et celle des transformations structurales en phase solide, tant du point de vue qualitatif que du point de vue quantitatif (mesure de l'energie de transformation du quartz {alpha} en quartz {beta} et determination de l'energie Wigner emmagasinee par l'oxyde de beryllium irradie aux neutrons). (auteur)

  15. [Method for direct generation data for formatted case report forms based on requirement for data authenticity in actual clinical conditions].

    Science.gov (United States)

    Shao, Ming-Yi; Liu, Bao-Yan; He, Li-Yun; Zhang, Run-Shun

    2013-04-01

    Data authenticity is the basic requirement of clinical studies. In actual clinical conditions how to establish formatted case report forms (CRF) in line with the requirement for data authenticity is the key to ensure clinical data quality. On the basis of the characteristics of clinical data in actual clinical conditions, we determined elements for establishing formatted case report forms by comparing differences in data characteristics of CRFs in traditional clinical studies and in actual clinical conditions, and then generated formatted case report forms in line with the requirement for data authenticity in actual clinical conditions. The data of formatted CRFs generated in this study could not only meet the requirement for data authenticity of clinical studies in actual clinical conditions, but also comply with data management practices for clinical studies, thus it is deemed as a progress in technical methods.

  16. Accurate characterization of 3D diffraction gratings using time domain discontinuous Galerkin method with exact absorbing boundary conditions

    KAUST Repository

    Sirenko, Kostyantyn

    2013-07-01

    Exact absorbing and periodic boundary conditions allow to truncate grating problems\\' infinite physical domains without introducing any errors. This work presents exact absorbing boundary conditions for 3D diffraction gratings and describes their discretization within a high-order time-domain discontinuous Galerkin finite element method (TD-DG-FEM). The error introduced by the boundary condition discretization matches that of the TD-DG-FEM; this results in an optimal solver in terms of accuracy and computation time. Numerical results demonstrate the superiority of this solver over TD-DG-FEM with perfectly matched layers (PML)-based domain truncation. © 2013 IEEE.

  17. Re-usable low density polyethylene aRm glove foR pueRpeRal ...

    African Journals Online (AJOL)

    2008-07-07

    Jul 7, 2008 ... Re-usable low density polyethylene aRm glove foR. pueRpeRal intRauteRine exploRation. o.n. MakindE, B.t. arEMo, B. arEMo, E.o. akinkunMi, f.a. Balogun, g.o. osinkolu and. W.o. siyanBola. abstRaCt. Objective: to design a long arm glove that can be used within a puerperal uterus to prevent the.

  18. FoCuS-point: software for STED fluorescence correlation and time-gated single photon counting

    DEFF Research Database (Denmark)

    Waithe, Dominic; Clausen, Mathias P; Sezgin, Erdinc

    2016-01-01

    microscopy (STED-FCS). Specifically, the use of gated detection has shown great potential for enhancing STED-FCS, but has also created a demand for software which is efficient and also implements the latest algorithms. Prior to this study, no open software has been available which would allow practical time...... to be established quickly and efficiently. AVAILABILITY AND IMPLEMENTATION: FoCuS-point is written in python and is available through the github repository: https://github.com/dwaithe/FCS_point_correlator. Furthermore, compiled versions of the code are available as executables which can be run directly in Linux...

  19. Devonian conodonts from the Foča–Prača Paleozoic complex (Durmitor Nappe, southeastern Bosnia and Herzegovina

    Directory of Open Access Journals (Sweden)

    Bogdan Jurkovšek

    2011-06-01

    Full Text Available Conodont study of the Crna Rijeka borehole CR-17, positioned in the frontal part of the Durmitor Nappe (Foča – Prača Paleozoic complex, SE Bosnia and Herzegovina is presented. The obtained fauna indicates an Early-Middle Devonian age and due to poor preservation an identification at a generic level is possible only. The recovered conodont elements have a high Color Alteration Index (CAI = 6,5–7 indicating a degree of metamorphism corresponding to a temperature interval from 440 °C to 720 °C.

  20. Comparison of two standard test methods for determining explosion limits of gases at atmospheric conditions.

    Science.gov (United States)

    De Smedt, G; de Corte, F; Notelé, R; Berghmans, J

    1999-12-31

    A comparison is made between two internationally accepted methods to determine the explosion limits of gases at atmospheric pressure and room temperature (20 l sphere - DIN 51649). Significant differences (about 1 vol.%) in the upper explosion limits (UEL) values are found for four hydrocarbons tested. A new criterion is proposed which leads to close agreement between the UEL values obtained by the two methods.

  1. THE INFLUENCE OF STORAGE CONDITIONS OF CANDIED FRUITS ENRICHED WITH VITAMIN C BY DIFFERENT METHODS ON ITS CONTENT

    Directory of Open Access Journals (Sweden)

    Agata Wypchoł

    2010-05-01

    Full Text Available The aim of this work was to study the effect of storage conditions of candied fruits enriched with vitamin C on its concentration in that product. The materials were candied fruits (black chokeberry and black currant enriched with vitamin C by two methods during their production. The final products were stored within 3 months at 8 and 20°C. On the basis of the results it was stated that enrichment method affected the concentration of the vitamin C in fruits measured during storage period at the above conditions. doi:10.5219/55

  2. Role of music in morphine rewarding effects in mice using conditioned place preference method.

    Science.gov (United States)

    Tavakoli, Farnaz; Hoseini, Seyed Ebrahim; Mokhtari, Mokhtar; Vahdati, Akbar; Razmi, Nematollah; Vessal, Mahmood

    2012-01-01

    This research aims at studying the neuroendocrine effects of music on creating morphine dependence in mice using conditioned place preference (CPP). The mice treated with 10 mg/kg morphine subcutaneously, fast music and slow music. Morphine was used to create dependence. In order to recognize the morphine rewarding effects, CPP technique was used. In the conditioning stage that lasted for 8 days, different groups of mice, after receiving the treatment were randomly placed in compartment for 30 minutes. The post-conditioning stage included the fourth day, the ninth day, the 12th day and the 16th day. Comparing place preference between morphine group and the control group, a significant increase (pmusic group compared with morphine group alone. In addition morphine + alone in the rain music group demonstrated a significantly increased conditioned place preference (pmusic acts as a positive pleasant emotion increasing the dopaminergic activity in the Nucleus Accumbens (NAc) and Ventral Tegmental Area (VTA) and through associated learning mechanisms of reward-related behavior increases morphine addiction. However, taxi girl music may act as unpleasant experiences producing negative emotions and reducing morphine addiction.

  3. Current Control Method for Distributed Generation Power Generation Plants under Grid Fault Conditions

    DEFF Research Database (Denmark)

    Rodriguez, Pedro; Luna, Alvaro; Hermoso, Juan Ramon

    2011-01-01

    The operation of distributed power generation systems under grid fault conditions is a key issue for the massive integration of renewable energy systems. Several studies have been conducted to improve the response of such distributed generation systems under voltage dips. In spite of being less s...

  4. Standard methods for maintaining adult Apis mellifera in cages under in vitro laboratory conditions

    NARCIS (Netherlands)

    Williams, G.R.; Alaux, C.; Costa, C.; Csaki, C.; Steen, van der J.J.M.

    2013-01-01

    Adult honey bees are maintained in vitro in laboratory cages for a variety of purposes. For example, researchers may wish to perform experiments on honey bees caged individually or in groups to study aspects of parasitology, toxicology, or physiology under highly controlled conditions, or they may

  5. Various conditioning methods for root canals influencing the tensile strength of titanium posts

    NARCIS (Netherlands)

    Schmage, P.; Sohn, J.; Nergiz, I.; Ozcan, M.; Nergiz, [No Value

    2004-01-01

    Conditioning the root canal is frequently advised to achieve high post-retention when resin composite luting cements are used. However, Manufacturers’ instructions for this purpose differ widely from one another. The aim of this study was to compare the tensile bond strengths of passive, tapered,

  6. A stable penalty method for the compressible Navier-Stokes equations: I. Open boundary conditions

    DEFF Research Database (Denmark)

    Hesthaven, Jan; Gottlieb, D.

    1996-01-01

    The purpose of this paper is to present asymptotically stable open boundary conditions for the numerical approximation of the compressible Navier-Stokes equations in three spatial dimensions. The treatment uses the conservation form of the Navier-Stokes equations and utilizes linearization...

  7. Shear bond strength of acrylic teeth to acrylic denture base after different surface conditioning methods.

    Science.gov (United States)

    Madhav, Gajula Venu; Raj, Soundar; Yadav, Naveen; Mudgal, Ishitha; Mehta, Nidhi; Tatwadiya, Riddhi

    2013-09-01

    Acrylic resin ruled the dental profession for 60 years, and this success is attributed to its aesthetics, handling properties, physical and biological compatibility, its stability in oral environment and its cost effectiveness. The objective of this study is to evaluate and compare the bond strength of acrylic resin teeth treated with various conditioning materials like monomer and silane coupling agent. METHDOLOGY: A study was carried out in which 96 samples were grouped into 3 groups with a sample size of 32 each (16 premolars, 16 molars). They were conditioned with different conditioning materials i,e monomer and silane coupling agent. Monomer, Silane coupling agent are coated on the ridge lap area before thermocycling and cured according to the manufacturer recommendations. The samples are retained from the fask; trimmed and polished. The samples are then subjected to shear bond strength using the Insteron Universal Testing Machine. In the present study it was found that application of monomer increased the bond strength between acrylic teeth and denture base, when compared to the conventionally processed samples. However it was found that application of silane coupling agent further increased the shear bond strength between acrylic teeth and denture base. Interprations and Within the confnes of this study it is found that there was a signifcant improvement in the bond strength between the acrylic teeth and denture base when silane coupling agent and monomer were used as surface conditioning material. The order of shear strength of samples is control > monomer > silane coupling agent.

  8. The Optimal Conditions for Form-Focused Instruction: Method, Target Complexity, and Types of Knowledge

    Science.gov (United States)

    Kim, Jeong-eun

    2012-01-01

    This dissertation investigates optimal conditions for form-focused instruction (FFI) by considering effects of internal (i.e., timing and types of FFI) and external (i.e., complexity and familiarity) variables of FFI when it is offered within a primarily meaning-focused context of adult second language (L2) learning. Ninety-two Korean-speaking…

  9. Evaluating a new method for reconstructing forest conditions from General Land Office survey records

    Science.gov (United States)

    Carrie R. Levine; Charles V. Cogbill; Brandon M. Collins; Andrew J. Larson; James A. Lutz; Malcolm P. North; Christina M. Restaino; Hugh D. Safford; Scott L. Stephens; John J. Battles

    2017-01-01

    Historical forest conditions are often used to inform contemporary management goals because historical forests are considered to be resilient to ecological disturbances. The General Land Office (GLO) surveys of the late 19th and early 20th centuries provide regionally quasi-contiguous data sets of historical forests across much of the Western United States....

  10. Novel method reveals a narrow phylogenetic distribution of bacterial dispersers in environmental communities exposed to low hydration conditions

    DEFF Research Database (Denmark)

    Krüger, U. S.; Bak, F.; Aamand, J.

    2018-01-01

    ), previously used to monitor dispersal of individual bacterial strains in liquid films at the surface of a porous ceramic disc. The novel procedure targets complex communities and captures the dispersed bacteria on a solid medium for growth and detection. The method was first validated by distinguishing motile......In this study, we developed a method that provides community-level surface dispersal profiles under controlled hydration conditions from environmental samples and enables us to isolate and uncover the diversity of the fastest bacterial dispersers. The method expands on the Porous Surface Model (PSM...... Pseudomonas putida and Flavobacterium johnsoniae strains from their non-motile mutants. Applying the method to soil and lake water bacterial communities showed that community-scale dispersal declined as conditions became drier. However, for both communities, dispersal was detected even under low hydration...

  11. A Methodical Development of Measures of Effectiveness for a Condition-Based Maintenance Management System

    Science.gov (United States)

    2014-06-01

    selecting a CMMS based on the desire to obtain a “silver bullet to magically fix inefficiency and ineffectiveness” (Autin 1998, 33). The following are...repeatable method to develop MOEs. Leibowitz discusses MOEs from a metaphysical operation analyst’s viewpoint. His approach resonates with Sproles’ call...Systems Integration: Theory, Metrics, and Methods. Boca Raton, FL: CRC Press. Leibowitz, Martin L. 1958. “ Metaphysical Considerations Involved in Choosing

  12. APPLICATION OFVISUALTEST METHODS LOADED ELEMENTS OF ROTATING MACHINERY FLOWTOASSESS THEIR CONDITION

    Directory of Open Access Journals (Sweden)

    Jan WARCZEK

    2016-03-01

    Full Text Available The article presents the aims and objectives of the process of non-destructive testing of turbine aircraft engines using visual methods indirect use of endoscopy. Presents brief characteristics of the construction of engines tested, analyzed the diagnostic procedures used in non-destructive testing methods are shown diagnostic equipment used in research. The paper presents examples of the results of diagnostic checks obtained for the test aircraft engine.

  13. A method for calculating the critical time under blowdown conditions during a SBLOCA

    International Nuclear Information System (INIS)

    Su Guanghui; Yu Zhenwan; Guo Yujun; Zhang Jinling; Qiu Suizheng; Jia Dounan

    1994-01-01

    The critical time is the period from the instant at which the blowdown occurs to the instant when the critical heat flux (CHF) happens. It determines the time of operating the safety protection system when a LOCA occurs in PWR. It is important to calculate the critical time correctly. The weakness of Griffith's method is analyzed and a great improvement is developed. The critical time calculated by the improved method agrees with the experimental values

  14. Conversion Method of the Balance Test Results in Open Jet Tunnel on the Free Flow Conditions

    Directory of Open Access Journals (Sweden)

    V. T. Bui

    2015-01-01

    Full Text Available The paper considers a problem of sizing a model and converting the balance test results in the low speed open-jet wind tunnel to free-flow conditions. The ANSYS Fluent commercial code performs flow model calculations in the test section and in the free flow, and the ANSYS ICEM CFD module is used to provide grid generation. A structured grid is generated in the free flow and an unstructured one is provided in the test section. The changes of aerodynamic coefficients are determined at the different values of the blockage factor for the segmental-conical and hemisphere cylinder-cone shapes of the model. The blockage factor values are found at which the interference of the test section – model is neglected. The paper presents a technique to convert the wind tunnel test results to the free flow conditions.

  15. Online calibration method for condition monitoring of nuclear reactor instrumentations based on electrical signature analysis

    International Nuclear Information System (INIS)

    Syaiful Bakhri

    2013-01-01

    Electrical signature analysis currently becomes an alternative in condition monitoring in nuclear power plants not only for stationary components such as sensors, measurement and instrumentation channels, and other components but also for dynamic components such as electric motors, pumps, generator or actuators. In order to guarantee the accuracy, the calibration of monitoring system is a necessary which practically is performed offline, under limited schedules and certain tight procedures. This research aims to introduce online calibration technique for electrical signature condition monitoring in order that the accuracy can be maintained continuously which in turn increases the reactor safety as a whole. The research was performed step by stepin detail from the conventional technique, online calibration using baseline information and online calibration using differential gain adjustment. Online calibration based on differential gain adjustment provides better results than other techniques even tough under extreme gain insertion as well as external disturbances such as supply voltages. (author)

  16. Determination of laser cutting process conditions using the preference selection index method

    Science.gov (United States)

    Madić, Miloš; Antucheviciene, Jurgita; Radovanović, Miroslav; Petković, Dušan

    2017-03-01

    Determination of adequate parameter settings for improvement of multiple quality and productivity characteristics at the same time is of great practical importance in laser cutting. This paper discusses the application of the preference selection index (PSI) method for discrete optimization of the CO2 laser cutting of stainless steel. The main motivation for application of the PSI method is that it represents an almost unexplored multi-criteria decision making (MCDM) method, and moreover, this method does not require assessment of the considered criteria relative significances. After reviewing and comparing the existing approaches for determination of laser cutting parameter settings, the application of the PSI method was explained in detail. Experiment realization was conducted by using Taguchi's L27 orthogonal array. Roughness of the cut surface, heat affected zone (HAZ), kerf width and material removal rate (MRR) were considered as optimization criteria. The proposed methodology is found to be very useful in real manufacturing environment since it involves simple calculations which are easy to understand and implement. However, while applying the PSI method it was observed that it can not be useful in situations where there exist a large number of alternatives which have attribute values (performances) very close to those which are preferred.

  17. Develop Accurate Methods for Characterizing and Quantifying Cohesive Sediment Erosion Under Combined Current-Wave Conditions

    Science.gov (United States)

    2017-09-01

    where sample core is inserted. Rubber seals have been waterproofed with silicon and secured with nuts and hex bolts. ................. 6 Figure 3...The addition of the miniLDV sensor will bring significant added benefit to the project, providing a coordination/comparison of several state-of-the...and amplitude operating condition generally requires a full day of testing and an additional 1–2 days for analysis of the PIV data for the

  18. Free vibration of symmetric angle ply truncated conical shells under different boundary conditions using spline method

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, K. K.; Aziz, Z. A.; Javed, Saira; Yaacob, Y. [Universiti Teknologi Malaysia, Johor Bahru (Malaysia); Pullepu, Babuji [S R M University, Chennai (India)

    2015-05-15

    Free vibration of symmetric angle-ply laminated truncated conical shell is analyzed to determine the effects of frequency parameter and angular frequencies under different boundary condition, ply angles, different material properties and other parameters. The governing equations of motion for truncated conical shell are obtained in terms of displacement functions. The displacement functions are approximated by cubic and quintic splines resulting into a generalized eigenvalue problem. The parametric studies have been made and discussed.

  19. CONDITIONS AND A METHODS OF TRANSPORT OF DANGEROUS GOODS BY AIR

    OpenAIRE

    Sandra Debeljak Rukavina

    2015-01-01

    The paper shows the international, European and national system of legal rules governing the transport of dangerous goods by air. With the review of the provisions of the Carriage of Dangerous Goods Act and the Final proposal on amendments to this national act, the paper elaborates on the provisions of the Ordinance on the conditions and manner of transport of dangerous goods by air that is in full compliance with Annex 18 to the Convention on International Civil Aviation (“Chicago Convention...

  20. Standard methods for maintaining adult Apis mellifera in cages under in vitro laboratory conditions

    OpenAIRE

    Williams, Geoffrey R.; Alaux, Cedric; Costa, Cecilia; Csaki, Tamas; Doublet, Vincent; Eisenhardt, Dorothea; Fries, Ingemar; Kuhn, Rolf; McMahon, Dino P.; Medrzycki, Piotr; Murray, Tomas E.; Natsopoulou, Myrsini E.; Neumann, Peter; Oliver, Randy; Paxton, Robert J.

    2013-01-01

    Adult honey bees are maintained in vitro in laboratory cages for a variety of purposes. For example, researchers may wish to perform experiments on honey bees caged individually or in groups to study aspects of parasitology, toxicology, or physiology under highly controlled conditions, or they may cage whole frames to obtain newly emerged workers of known age cohorts. Regardless of purpose, researchers must manage a number of variables, ranging from selection of study subjects (e.g. honey bee...

  1. Standard methods for maintaining adult Apis mellifera in cages under in vitro laboratory conditions

    OpenAIRE

    Williams, G.R.; Alaux, C.; Costa, C.; Csaki, C.; Steen, van der, J.J.M.

    2013-01-01

    Adult honey bees are maintained in vitro in laboratory cages for a variety of purposes. For example, researchers may wish to perform experiments on honey bees caged individually or in groups to study aspects of parasitology, toxicology, or physiology under highly controlled conditions, or they may cage whole frames to obtain freshly emerged workers of known age cohorts. Regardless of purpose, researchers must manage a number of variables, ranging from selection of study subjects (e.g. honey b...

  2. Effective As(III) Removal by A Multi-Charged Hydroacid Complex Draw Solute Facilitated Forward Osmosis-Membrane Distillation (FO-MD) Processes.

    Science.gov (United States)

    Ge, Qingchun; Han, Gang; Chung, Tai-Shung

    2016-03-01

    Effective removal of As(III) from water by an oxalic acid complex with the formula of Na3[Cr(C2O4)3] (Na-Cr-OA) is demonstrated via an forward osmosis-membrane distillation (FO-MD) hybrid system in this study. Na-Cr-OA first proved its superiority as a draw solute with high water fluxes and negligible reverse fluxes in FO, then a systematic investigation of the Na-Cr-OA promoted FO process was conducted to ascertain the factors in As(III) removal. Relatively high water fluxes of 28 LMH under the FO mode and 74 LMH under the pressure retarded osmosis (PRO) mode were achieved when using a 1000 ppm As(III) solution as the feed and 1.0 M Na-Cr-OA as the draw solution at 60 °C. As(III) removal with a water recovery up to 21.6% (FO mode) and 48.3% (PRO mode) were also achieved in 2 h. An outstanding As(III) rejection with 30-3000 μg/L As(III) in the permeate was accomplished when As(III) feed solutions varied from 5 × 10(4) to 1 × 10(6) μg/L, superior to the best FO performance reported for As(III) removal. Incorporating MD into FO not only makes As(III) removal sustainable by reconcentrating the Na-Cr-OA solution simultaneously, but also reduces the As(III) concentration below 10 μg/L in the product water, meeting the WHO standard.

  3. Neural-network-based prediction techniques for single station modeling and regional mapping of the foF2 and M(3000F2 ionospheric characteristics

    Directory of Open Access Journals (Sweden)

    T. D. Xenos

    2002-01-01

    Full Text Available In this work, Neural-Network-based single-station hourly daily foF2 and M(3000F2 modelling of 15 European ionospheric stations is investigated. The data used are neural networks and hourly daily values from the period 1964- 1988 for training the neural networks and from the period 1989-1994 for checking the prediction accuracy. Two types of models are presented for the F2-layer critical frequency prediction and two for the propagation factor M(3000F2. The first foF2 model employs the E-layer local noon calculated daily critical frequency (foE12 and the local noon F2- layer critical frequency of the previous day. The second foF2 model, which introduces a new regional mapping technique, employs the Juliusruh neural network model and uses the E-layer local noon calculated daily critical frequency (foE12, and the previous day F2-layer critical frequency measured at Juliusruh at noon. The first M(3000F2 model employs the E-layer local noon calculated daily critical frequency (foE12, its ± 3 h deviations and the local noon cosine of the solar zenith angle (cos c12. The second model, which introduces a new M(3000F2 mapping technique, employs Juliusruh neural network model and uses the E-layer local noon calculated daily critical frequency (foE12, and the previous day F2-layer critical frequency measured at Juliusruh at noon.

  4. Effective As(III) Removal by A Multi-Charged Hydroacid Complex Draw Solute Facilitated Forward Osmosis-Membrane Distillation (FO-MD) Processes

    KAUST Repository

    Ge, Qingchun

    2016-01-29

    © 2016 American Chemical Society. Effective removal of As(III) from water by an oxalic acid complex with the formula of Na3[Cr(C2O4)3] (Na-Cr-OA) is demonstrated via an forward osmosis-membrane distillation (FO-MD) hybrid system in this study. Na-Cr-OA first proved its superiority as a draw solute with high water fluxes and negligible reverse fluxes in FO, then a systematic investigation of the Na-Cr-OA promoted FO process was conducted to ascertain the factors in As(III) removal. Relatively high water fluxes of 28 LMH under the FO mode and 74 LMH under the pressure retarded osmosis (PRO) mode were achieved when using a 1000 ppm As(III) solution as the feed and 1.0 M Na-Cr-OA as the draw solution at 60 °C. As(III) removal with a water recovery up to 21.6% (FO mode) and 48.3% (PRO mode) were also achieved in 2 h. An outstanding As(III) rejection with 30-3000 μg/L As(III) in the permeate was accomplished when As(III) feed solutions varied from 5 × 104 to 1 × 106 μg/L, superior to the best FO performance reported for As(III) removal. Incorporating MD into FO not only makes As(III) removal sustainable by reconcentrating the Na-Cr-OA solution simultaneously, but also reduces the As(III) concentration below 10 μg/L in the product water, meeting the WHO standard.

  5. Apparatus and method for non-invasive diagnosis and control of motor operated valve condition

    Science.gov (United States)

    Lyon, R.H.; Chai, J.; Lang, J.H.; Hagman, W.H.; Umans, S.D.; Saarela, O.J.

    1997-01-14

    An apparatus compares the torque from an MOV motor with the valve displacement, and from the comparison assesses MOV operating condition. A transducer measures the vibration of the housing of an MOV. The vibrations are due to the motions of the rotating elements within the housing, which motions are directly related to the motion of the valve relative to its seat. Signal processing apparatus analyzes the vibrations to recover the rotations of the rotating elements and thus the motion of the valve plug. Lost motion can also be determined (if a lost motion connection exists) by demodulating the vibration signal and thus taking into account also the lost motion. Simultaneously, the forces applied to the valve are estimated by estimating the torque between the stator and the rotor of the motor. Such torque can be estimated from measuring the input current and voltage alone, using a forgetting factor and a correction for the forgetting factor. A signature derived from relating the torque to the valve position can be used to assess the condition of the MOV, by comparing the signature to signatures for MOVs of known conditions. The vibration analysis components generate signals that relate to the position of elements in the operator. Similarly, the torque estimator estimates the torque output by any type of electric motor, whether or not part of an MOV analysis unit. 28 figs.

  6. ARE METHODS USED TO INTEGRATE STANDARDIZED MANAGEMENT SYSTEMS A CONDITIONING FACTOR OF THE LEVEL OF INTEGRATION? AN EMPIRICAL STUDY

    Directory of Open Access Journals (Sweden)

    Merce Bernardo

    2011-09-01

    Full Text Available Organizations are increasingly implementing multiple Management System Standards (M SSs and considering managing the related Management Systems (MSs as a single system.The aim of this paper is to analyze if methods us ed to integrate standardized MSs condition the level of integration of those MSs. A descriptive methodology has been applied to 343 Spanish organizations registered to, at least, ISO 9001 and ISO 14001. Seven groups of these organizations using different combinations of methods have been analyzed Results show that these organizations have a high level of integration of their MSs. The most common method used, was the process map. Organizations using a combination of different methods achieve higher levels of integration than those using a single method. However, no evidence has been found to confirm the relationship between the method used and the integration level achieved.

  7. A comparison of estimation methods for computational fluid dynamics outflow boundary conditions using patient-specific carotid artery.

    Science.gov (United States)

    Lee, Chang-Joon; Uemiya, Nahoko; Ishihara, Shoichiro; Zhang, Yu; Qian, Yi

    2013-06-01

    Computational fluid dynamics simulations can provide important hemodynamic insights for investigating the effectiveness of carotid artery stenting, but its accuracy is dependent on the boundary conditions such as the outflow pressure, which is difficult to obtain by measurements. Many computational fluid dynamics simulations assume that the outflow pressure is constant (P = 0), but this method is likely to produce different results compared to clinical measurements. We have developed an alternative estimation method called the minimum energy loss method based on the concept of energy loss minimization at flow bifurcation. This new method has been tested on computational fluid dynamics simulation of two patients treated with carotid artery stenting, and its flow ratio at internal carotid artery and wall shear stress distribution was compared with the constant zero outlet pressure method. Three different procedure stages (prestent, poststent, and follow-up) were analyzed. The internal carotid artery flow ratio using the minimum energy loss method generally matched well with ultrasound measurements, but the internal carotid artery flow ratio based on zero outlet pressure method showed a large difference. Wall shear stress distributions varied between methods in response to the change in internal carotid artery flow rate. This study demonstrates the importance of accurate outlet boundary condition for assessing the long-term efficacy of carotid artery stenting and the risk of restenosis in treated patients.

  8. METHODS OF CALCULATING DISCOUNT AND CAPITALIZATION RATES TO VALUATING REAL ESTATE IN ACCORDANCE WITH MARKETS CONDITIONS

    Directory of Open Access Journals (Sweden)

    L. Chubuk

    2013-09-01

    Full Text Available The existent methods of determination of the discount and capitalization rates for the valuation of the profitable real estate are analyzed from point of their prevalence, advantages and lacks of application. The alternative methods for setting the discount rates are selected (Galasyuk’s method. There are resulted recommendations in relation to approaching calculated size of the discount and capitalization rates to the real market information. In particular, expansion of the use of actually attained level of the expected return on the invested capital is offered. The actual values of capitalization rates on the office, commercial, ware-house real estate market in the capital of Ukraine are examined for period from 2008 to 2013, which evidence of considerable changeability of investment return indexes. There is confirmed the necessity of increasing the size of corrections in supply price to the level 18-20% for calculation of the capitalization rates after the method of market extraction. There is also propagates the account of additional market factors at the construction of recapitalization rates after the Invud’s method: annual growth (decline of leasing rates that are obtained from the profit real estate object; annual growth (decline of cost of the real property object; a percent of diminishing of cost of the real estate object in result of all kinds of depreciation (when residual value differ from a zero.

  9. Finite-element methods for the streamfunction-vorticity equations: Boundary-condition treatments and multiply connected domains

    International Nuclear Information System (INIS)

    Gunzburger, M.D.; Peterson, J.S.

    1988-01-01

    Finite-element methods for the approximation of the solution of streamfunction-vorticity equations are considered. Among the issues dealt with are multiply connected domains, the use of low-order elements, the incorporation of a variety of boundary conditions into the methodology, error estimates, and the recovery of the primitive variables. Various numerical examples are also provided

  10. Diagnostics of Technical Condition of Gear Units of Belt Conveyors for the Aggregate of Methods of Nondestructive Testing

    Science.gov (United States)

    Kuzin, Evgeny G.; Gerike, Boris L.; Drozdenko, Yuriy V.; Lupiy, Michael G.; Grigoryeva, Natalya V.

    2017-10-01

    The article reviews the issues of complex use of methods of technical diagnostics of gearboxes for belt conveyors, with the aim of creating an effective system of maintenance. The article is showing the results of the evaluation of the technical condition of the drives of belt conveyors based on vibration monitoring and thermal parameters, and analysis of lubricating oil.

  11. Transportable activation facility for preparation of radioactive sodium under industrial conditions to study boreholes by isotope methods

    International Nuclear Information System (INIS)

    Kostin, Yu.I.; Zajchenkov, B.D.; Ibatullin, R.A.; Gulin, Yu.A.; Tugarinov, L.N.

    1981-01-01

    A method of short-living isotope production at the place their application is proposed. A transportable activation facility for the preparation of radioactive sodium under industrial conditions was developed to radioactive tracer logging. Facility specifications and its application results are given [ru

  12. Transportable activation facility for preparation of radioactive sodium under industrial conditions to study boreholes by isotope methods

    Energy Technology Data Exchange (ETDEWEB)

    Kostin, Yu.I.; Zajchenkov, B.D.; Ibatullin, R.A.; Gulin, Yu.A.; Tugarinov, L.N. (Vsesoyuznyj Nauchno-Issledovatel' skij i Proektno-Konstruktorskij Inst. Geofizicheskikh Issledovanij Geologorazvedochnykh Skvazhin, Oktyabr' skij (USSR))

    1981-01-01

    A method of short-living isotope production at the place their application is proposed. A transportable activation facility for the preparation of radioactive sodium under industrial conditions was developed to radioactive tracer logging. Facility specifications and its application results are given.

  13. Optimization of Spherical Cap Mascon Processing on the Ice Sheets for the GRACE and GRACE-FO Missions

    Science.gov (United States)

    Mohajerani, Y.; Velicogna, I.

    2016-12-01

    The GRACE mission has been providing time-variable gravity data crucial to studying the earth system since 2002, and the record will continue with the launch of the GRACE Follow-On (FO) mission in 2017. One way to obtain regional surface mass change estimates is fitting the GRACE data to regionally defined areas - "mascons" - in the harmonic domain. While previous studies using spherical cap mascons have considered uniform distributions, here we design a dynamic mascon design that can be optimized in both size and position based on the spatial pattern of signal to noise ratio for different regions. We use centroidal Voronoi tessellations to optimize the packing of the mascons to avoid leakage, and we develop regionally-tailored density functions to take advantage of the signal-to-noise ratio. We focus on the Greenland and Antarctic ice sheets and develop refined mascons for areas of high mass change. Regional time-series are also compared with independent datasets such as altimetry and regional climate models. We also evaluate the improvements by performing synthetic tests assuming GRACE-FO errors. These dynamic mascons allow for improved regional time-series, which can result in better quantification and understanding of changes in the cryosphere.

  14. Acoustic model order reduction for the lowest condition number in inverse method

    Science.gov (United States)

    Madoliat, Reza; Nouri, Nowrouz Mohammad; Rahrovi, Ali

    2017-06-01

    Acoustic sources with wide surfaces can be broken down in a fluid environment into smaller acoustic sources. In this study, a general model is presented, indicating the type, number, direction, position and strength of these sources in such a way that the main sound and the sound of the equivalent sources match each other acceptably. When the position and direction of the source is determined, the strength of the source can be found using the inverse method. However, since the solution is not unique in the inverse method, a different acoustic strength is obtained for the sources if different positions are selected. By selecting an arrangement of general sources and using an optimization algorithm, the least possible mismatch between the main sound and the sound of equivalent sources can be achieved. In the inverse method, it is important to reduce the effects of measurement errors. The sensor placement and acoustic model order reduction (AMOR) are studied for reducing these effects.

  15. Selection of Investment Projects by Monte Carlo Method in Risk Condition

    Directory of Open Access Journals (Sweden)

    M. E.

    2017-12-01

    Full Text Available The Monte Carlo method (also known as the Monte Carlo simulation was proposed by Nicholas Metropolis, S. Ulam and Jhon Von Neiman in 50-th years of the past century. The method can be widely applied to analysis of investment projects due to the advantages recognized both by practitioners and the academic community. The balance model of a project with discounted financial flows has been implemented for Microsoft Excel and Google Docs spread-sheet solutions. The Monte Carlo method for project with low and high correlated net present value (NPV parameters in the environment of the electronic tables of MS Excel/Google Docs. A distinct graduation of risk was identified. A necessity of account of correlation effects and the use of multivariate imitation during the project selection has been demonstrated.

  16. Use of an Accurate DNS Particulate Flow Method to Supply and Validate Boundary Conditions for the MFIX Code

    Energy Technology Data Exchange (ETDEWEB)

    Zhi-Gang Feng

    2012-05-31

    The simulation of particulate flows for industrial applications often requires the use of two-fluid models, where the solid particles are considered as a separate continuous phase. One of the underlining uncertainties in the use of the two-fluid models in multiphase computations comes from the boundary condition of the solid phase. Typically, the gas or liquid fluid boundary condition at a solid wall is the so called no-slip condition, which has been widely accepted to be valid for single-phase fluid dynamics provided that the Knudsen number is low. However, the boundary condition for the solid phase is not well understood. The no-slip condition at a solid boundary is not a valid assumption for the solid phase. Instead, several researchers advocate a slip condition as a more appropriate boundary condition. However, the question on the selection of an exact slip length or a slip velocity coefficient is still unanswered. Experimental or numerical simulation data are needed in order to determinate the slip boundary condition that is applicable to a two-fluid model. The goal of this project is to improve the performance and accuracy of the boundary conditions used in two-fluid models such as the MFIX code, which is frequently used in multiphase flow simulations. The specific objectives of the project are to use first principles embedded in a validated Direct Numerical Simulation particulate flow numerical program, which uses the Immersed Boundary method (DNS-IB) and the Direct Forcing scheme in order to establish, modify and validate needed energy and momentum boundary conditions for the MFIX code. To achieve these objectives, we have developed a highly efficient DNS code and conducted numerical simulations to investigate the particle-wall and particle-particle interactions in particulate flows. Most of our research findings have been reported in major conferences and archived journals, which are listed in Section 7 of this report. In this report, we will present a

  17. Modelling of Non-Premixed Turbulent Combustion of Hydrogen using Conditional Moment Closure Method

    International Nuclear Information System (INIS)

    Noor, M M; Hairuddin, A Aziz; Wandel, Andrew P; Yusaf, T F

    2012-01-01

    Most of the electricity generation and energy for transport is still generated by the conversion of chemical to mechanical energy by burning the fuels in the combustion chamber. Regulation for pollution and the demand for more fuel economy had driven worldwide researcher to focus on combustion efficiency. In order to reduce experimental cost, accurate modelling and simulation is very critical step. Taylor series expansion was utilised to reduce the error term for the discretization. FORTRAN code was used to execute the discretized partial differential equation. Hydrogen combustion was simulated using Conditional Moment Closure (CMC) model. Combustion of hydrogen with oxygen was successfully simulated and reported in this paper.

  18. Exo-metabolome of Pseudovibrio sp. FO-BEG1 analyzed by ultra-high resolution mass spectrometry and the effect of phosphate limitation.

    Directory of Open Access Journals (Sweden)

    Stefano Romano

    Full Text Available Oceanic dissolved organic matter (DOM is an assemblage of reduced carbon compounds, which results from biotic and abiotic processes. The biotic processes consist in either release or uptake of specific molecules by marine organisms. Heterotrophic bacteria have been mostly considered to influence the DOM composition by preferential uptake of certain compounds. However, they also secrete a variety of molecules depending on physiological state, environmental and growth conditions, but so far the full set of compounds secreted by these bacteria has never been investigated. In this study, we analyzed the exo-metabolome, metabolites secreted into the environment, of the heterotrophic marine bacterium Pseudovibrio sp. FO-BEG1 via ultra-high resolution mass spectrometry, comparing phosphate limited with phosphate surplus growth conditions. Bacteria belonging to the Pseudovibrio genus have been isolated worldwide, mainly from marine invertebrates and were described as metabolically versatile Alphaproteobacteria. We show that the exo-metabolome is unexpectedly large and diverse, consisting of hundreds of compounds that differ by their molecular formulae. It is characterized by a dynamic recycling of molecules, and it is drastically affected by the physiological state of the strain. Moreover, we show that phosphate limitation greatly influences both the amount and the composition of the secreted molecules. By assigning the detected masses to general chemical categories, we observed that under phosphate surplus conditions the secreted molecules were mainly peptides and highly unsaturated compounds. In contrast, under phosphate limitation the composition of the exo-metabolome changed during bacterial growth, showing an increase in highly unsaturated, phenolic, and polyphenolic compounds. Finally, we annotated the detected masses using multiple metabolite databases. These analyses suggested the presence of several masses analogue to masses of known bioactive

  19. A prediction method based on grey system theory in equipment condition based maintenance

    International Nuclear Information System (INIS)

    Yan, Shengyuan; Yan, Shengyuan; Zhang, Hongguo; Zhang, Zhijian; Peng, Minjun; Yang, Ming

    2007-01-01

    Grey prediction is a modeling method based on historical or present, known or indefinite information, which can be used for forecasting the development of the eigenvalues of the targeted equipment system and setting up the model by using less information. In this paper, the postulate of grey system theory, which includes the grey generating, the sorts of grey generating and the grey forecasting model, is introduced first. The concrete application process, which includes the grey prediction modeling, grey prediction, error calculation, equal dimension and new information approach, is introduced secondly. Application of a so-called 'Equal Dimension and New Information' (EDNI) technology in grey system theory is adopted in an application case, aiming at improving the accuracy of prediction without increasing the amount of calculation by replacing old data with new ones. The proposed method can provide a new way for solving the problem of eigenvalue data exploding in equal distance effectively, short time interval and real time prediction. The proposed method, which was based on historical or present, known or indefinite information, was verified by the vibration prediction of induced draft fan of a boiler of the Yantai Power Station in China, and the results show that the proposed method based on grey system theory is simple and provides a high accuracy in prediction. So, it is very useful and significant to the controlling and controllable management in safety production. (authors)

  20. Improved Method of Detection Falsification Results the Digital Image in Conditions of Attacks

    Directory of Open Access Journals (Sweden)

    Kobozeva A.A.

    2016-08-01

    Full Text Available The modern level of information technologies development has led to unheard ease embodiments hitherto unauthorized modifications of digital content. At the moment, very important question is the effective expert examination of authenticity of digital images, video, audio, development of the methods for identification and localization of violations of their integrity using these contents for purposes other than entertainment. Present paper deals with the improvement of the detection method of the cloning results in digital images - one of the most frequently used in the software tools falsification realized in all modern graphics editors. The method is intended for clone detection areas and pre-image in terms of additional disturbing influences in the image after the cloning operation for "masking" of the results, which complicates the search process. The improvement is aimed at reducing the number of "false alarms", when the area of the clone / pre-image detected in the original image or the localization of the identified areas do not correspond to the real clone and pre-image. The proposed improvement, based on analysis of different sizes per-pixel image blocks with the least difference from each other, has made it possible efficient functioning of the method, regardless of the specificity of the analyzed digital image.

  1. Homotopy Method for a General Multiobjective Programming Problem under Generalized Quasinormal Cone Condition

    Directory of Open Access Journals (Sweden)

    X. Zhao

    2012-01-01

    Full Text Available A combined interior point homotopy continuation method is proposed for solving general multiobjective programming problem. We prove the existence and convergence of a smooth homotopy path from almost any interior initial interior point to a solution of the KKT system under some basic assumptions.

  2. A revised method for assessing veld condition. | N.M. | African ...

    African Journals Online (AJOL)

    These and additional, subjectively assessed parameters of the veld being evaluated, are compared to those of the benchmark - a site chosen to represent the agro-ecological ideal for the area. These data are then used to estimate the current grazing capacity. The method has been adapted to bushveld sites, where an ...

  3. New Methods for Evaluation of Spent Fuel Condition during Long-Term Storage in Slovakia

    Directory of Open Access Journals (Sweden)

    M. Mikloš

    2009-01-01

    Full Text Available Experiences with an advanced spent nuclear fuel management in Slovakia are presented in this paper. The evaluation and monitoring procedures are based on practices at the Slovak wet interim spent fuel storage facility in NPP Jaslovské Bohunice. Since 1999, leak testing of WWER-440 fuel assemblies are provided by special leak tightness detection system “Sipping in pool” delivered by Framatomeanp with external heating for the precise defects determination. In 2006, a new inspection stand “SVYP-440” for monitoring of spent nuclear fuel condition was inserted. This stand has the possibility to open WWER-440 fuel assemblies and examine fuel elements. Optimal ways of spent fuel disposal and monitoring of nuclear fuel condition were designed. With appropriate approach of conservativeness, new factor for specifying spent fuel leak tightness is introduced in the paper. By using computer simulations (based on SCALE 4.4a code for fission products creation and measurements by system “Sipping in pool,” the limit values of leak tightness were established.

  4. Controlled particle removal from surfaces by electrodynamic methods for terrestrial, lunar, and Martian environmental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Calle, C I; Mantovani, J G [Electrostatics and Surface Physics Laboratory, NASA, Kennedy Space Center, FL 32899 (United States); Mazumder, M K [Department of Applied Science, University of Arkansas, Little Rock, AK 72204 (United States); Immer, C D; Buhler, C R [ASRC Aerospace, Kennedy Space Center, FL 32899 (United States); Clements, J S; Lundeen, P [Physics Department, Appalachian State University, Boone, NC 28608 (United States); Chen, A [Physics Department, Oklahoma Baptist University, Shawnee, OK 74804 (United States)], E-mail: carlos.i.calle@nasa.gov

    2008-12-01

    An Electrodynamic Dust Shield to remove already deposited micron-size particles from surfaces and to prevent the accumulation of such particles on surfaces has been developed. In addition to terrestrial application, our NASA laboratory is adapting this technology for the dusty and harsh environments of the Moon and Mars. The Apollo missions to the moon showed that lunar dust can hamper astronaut surface activities due to its ability to cling to most surfaces. NASA's Mars exploration landers and rovers have also shown that the problem is equally hard if not harder on Mars. In this paper, we show that an appropriate design can prevent the electrostatic breakdown at the low Martian atmospheric pressures. We are also able to show that uncharged dust can be lifted and removed from surfaces under simulated Martian environmental conditions. This technology has many potential benefits for removing dust from visors, viewports and many other surfaces as well as from solar arrays. We have also been able to develop a version of the electrodynamic dust shield working under hard vacuum conditions. This version should work well on the moon. We present data on the design and optimization of both types of dust shields as well substantial data on the clearing factors for transparent dust shields designed to protect solar panels for Martian exploration.

  5. Controlled particle removal from surfaces by electrodynamic methods for terrestrial, lunar, and Martian environmental conditions

    International Nuclear Information System (INIS)

    Calle, C I; Mantovani, J G; Mazumder, M K; Immer, C D; Buhler, C R; Clements, J S; Lundeen, P; Chen, A

    2008-01-01

    An Electrodynamic Dust Shield to remove already deposited micron-size particles from surfaces and to prevent the accumulation of such particles on surfaces has been developed. In addition to terrestrial application, our NASA laboratory is adapting this technology for the dusty and harsh environments of the Moon and Mars. The Apollo missions to the moon showed that lunar dust can hamper astronaut surface activities due to its ability to cling to most surfaces. NASA's Mars exploration landers and rovers have also shown that the problem is equally hard if not harder on Mars. In this paper, we show that an appropriate design can prevent the electrostatic breakdown at the low Martian atmospheric pressures. We are also able to show that uncharged dust can be lifted and removed from surfaces under simulated Martian environmental conditions. This technology has many potential benefits for removing dust from visors, viewports and many other surfaces as well as from solar arrays. We have also been able to develop a version of the electrodynamic dust shield working under hard vacuum conditions. This version should work well on the moon. We present data on the design and optimization of both types of dust shields as well substantial data on the clearing factors for transparent dust shields designed to protect solar panels for Martian exploration.

  6. Innovative Equipment and Production Method for Mixed Fodder in the Conditions of Agricultural Enterprises

    Science.gov (United States)

    Sabiev, U. K.; Demchuk, E. V.; Myalo, V. V.; Soyunov, A. S.

    2017-07-01

    It is recommended to feed the cattle and poultry with grain fodder in the form of feed mixture balanced according to the content. Feeding of grain fodder in the form of stock feed is inefficient and economically unreasonable. The article is devoted to actual problem - the preparation of mixed fodder in the conditions of agricultural enterprises. Review and critical analyses of mixed fodder assemblies and aggregates are given. Structural and technical schemes of small-size mixed fodder aggregate with intensified attachments of vibrating and percussive action for preparation of bulk feed mixture in the conditions of agricultural enterprises were developed. The mixed fodder aggregate for its preparation in the places of direct consumption from own grain fodder production and purchased protein and vitamin supplements is also suggested. Mixed fodder aggregate allows to get prepared mixed fodder of high uniformity at low cost of energy and price of production that is becoming profitable for livestock breeding. Model line-up of suggested mixed fodder aggregate with different productivity both for small and big agricultural enterprises is considered.

  7. Discrete Boltzmann Method with Maxwell-Type Boundary Condition for Slip Flow

    Science.gov (United States)

    Zhang, Yu-Dong; Xu, Ai-Guo; Zhang, Guang-Cai; Chen, Zhi-Hua

    2018-01-01

    The rarefied effect of gas flow in microchannel is significant and cannot be well described by traditional hydrodynamic models. It has been known that discrete Boltzmann model (DBM) has the potential to investigate flows in a relatively wider range of Knudsen number because of its intrinsic kinetic nature inherited from Boltzmann equation. It is crucial to have a proper kinetic boundary condition for DBM to capture the velocity slip and the flow characteristics in the Knudsen layer. In this paper, we present a DBM combined with Maxwell-type boundary condition model for slip flow. The tangential momentum accommodation coefficient is introduced to implement a gas-surface interaction model. Both the velocity slip and the Knudsen layer under various Knudsen numbers and accommodation coefficients can be well described. Two kinds of slip flows, including Couette flow and Poiseuille flow, are simulated to verify the model. To dynamically compare results from different models, the relation between the definition of Knudsen number in hard sphere model and that in BGK model is clarified. Support of National Natural Science Foundation of China under Grant Nos. 11475028, 11772064, and 11502117 Science Challenge Project under Grant Nos. JCKY2016212A501 and TZ2016002

  8. Focus adjustment method for CBERS 3 and 4 satellites Mux camera to be performed in air condition and its experimental verification for best performance in orbital vacuum condition

    Science.gov (United States)

    Scaduto, Lucimara C. N.; Malavolta, Alexandre T.; Modugno, Rodrigo G.; Vales, Luiz F.; Carvalho, Erica G.; Evangelista, Sérgio; Stefani, Mario A.; de Castro Neto, Jarbas C.

    2017-11-01

    The first Brazilian remote sensing multispectral camera (MUX) is currently under development at Opto Eletronica S.A. It consists of a four-spectral-band sensor covering a 450nm to 890nm wavelength range. This camera will provide images within a 20m ground resolution at nadir. The MUX camera is part of the payload of the upcoming Sino-Brazilian satellites CBERS 3&4 (China-Brazil Earth Resource Satellite). The preliminary alignment between the optical system and the CCD sensor, which is located at the focal plane assembly, was obtained in air condition, clean room environment. A collimator was used for the performance evaluation of the camera. The preliminary performance evaluation of the optical channel was registered by compensating the collimator focus position due to changes in the test environment, as an air-to-vacuum environment transition leads to a defocus process in this camera. Therefore, it is necessary to confirm that the alignment of the camera must always be attained ensuring that its best performance is reached for an orbital vacuum condition. For this reason and as a further step on the development process, the MUX camera Qualification Model was tested and evaluated inside a thermo-vacuum chamber and submitted to an as-orbit vacuum environment. In this study, the influence of temperature fields was neglected. This paper reports on the performance evaluation and discusses the results for this camera when operating within those mentioned test conditions. The overall optical tests and results show that the "in air" adjustment method was suitable to be performed, as a critical activity, to guarantee the equipment according to its design requirements.

  9. Stress-Based Finite Element Methods for Dynamics Analysis of Euler-Bernoulli Beams with Various Boundary Conditions

    Directory of Open Access Journals (Sweden)

    Majid Gholampour

    Full Text Available Abstract In this research, two stress-based finite element methods including the curvature-based finite element method (CFE and the curvature-derivative-based finite element method (CDFE are developed for dynamics analysis of Euler-Bernoulli beams with different boundary conditions. In CFE, the curvature distribution of the Euler-Bernoulli beams is approximated by its nodal curvatures then the displacement distribution is obtained by its integration. In CDFE, the displacement distribution is approximated in terms of nodal curvature derivatives by integration of the curvature derivative distribution. In the introduced methods, compared with displacement-based finite element method (DFE, not only the required number of degrees of freedom is reduced, but also the continuity of stress at nodal points is satisfied. In this paper, the natural frequencies of beams with different type of boundary conditions are obtained using both CFE and CDFE methods. Furthermore, some numerical examples for the static and dynamic response of some beams are solved and compared with those obtained by DFE method.

  10. Nu–Ra–Fo correlations for thermal control of embarked radars contained in tilted hemispherical cavities and subjected to constant heat flux

    International Nuclear Information System (INIS)

    Baïri, A.

    2014-01-01

    This work is intended to improve the operation of on-board radar systems contained in the disk of an inclined air-filled hemispherical cavity. When the device is switched on, its thermal behaviour is driven by the transient convection heat transfer that precedes the steady state. The heat flux density imposed on the device, the radius of the disk and its inclination with respect to the horizontal are the most influential parameters on this phenomenon. Nusselt–Rayleigh-Fourier correlations are proposed to calculate the transient convective heat exchanges. These relationships cover a wide range of Rayleigh numbers varying between 10 4 and 3.2 × 10 11 and inclination angles comprised between 0° (horizontal cavity) and 90° (vertical cavity) in steps of 15°. These results are obtained by numerical approach based on the finite volume method and supplement steady state correlations presented in previous works validated experimentally. The large Rayleigh number and inclinations ranges considered in this work allow application of the proposed correlations in several other engineering fields such as solar energy, security of persons, domotics or installation safety. - Highlights: •Quantification of transient natural convective heat transfer. •Nu–Ra–Fo correlations for large Ra range and constant heat flux. •Hemispherical air-filled inclined cavity. •Improvement of on-board radars performances. •Numerical approach

  11. Early forecasting of crop condition using an integrative remote sensing method for corn and soybeans in Iowa and Illinois, USA

    Science.gov (United States)

    Seo, Bumsuk; Lee, Jihye; Kang, Sinkyu

    2017-04-01

    The weather-related risks in crop production is not only crucial for farmers but also for market participants and policy makers since securing food supply is an important issue for society. While crop growth condition and phenology are essential information about such risks, the extensive observations on those are often non-existent in many parts of the world. In this study, we have developed a novel integrative approach to remotely sense crop growth condition and phenology at a large scale. For corn and soybeans in Iowa and Illinois of USA (2003-2014), we assessed crop growth condition and crop phenology by EO data and validated it against the United States Department of Agriculture (USDA) National Agriculture Statistics System (NASS) crop statistics. For growth condition, we used two distinguished approaches to acquire crop condition indicators: a process-based crop growth modelling and a satellite NDVI based method. Based on their pixel-wise historic distributions, we determined relative growth conditions and scaled-down to the state-level. For crop phenology, we calculated three crop phenology metrics [i.e., start of season (SOS), end of season (EOS), and peak of season (POS)] at the pixel level from MODIS 8-day Normalized Difference Vegetation Index (NDVI). The estimates were compared with the Crop Progress and Condition (CPC) data of NASS. For the condition, the state-level 10-day estimates showed a moderate agreement (RMSE 70%). Notably, the condition estimates corresponded to the severe soybeans disease in 2003 and the drought in 2012 for both crops. For the phenology, the average RMSE of the estimates was 8.6 day for the all three metrics. The average |ME| was smaller than 1.0 day after bias correction. The proposed method enables us to evaluate crop growth at any given period and place. Global climate changes are increasing the risk in agricultural production such as long-term drought. We hope that the presented remote sensing method for crop condition

  12. ASSESSMENT OF HYDROMORPHOLOGICAL CONDITIONS OF URBAN STREAMS WITH URBAN RIVER SURVEY METHOD

    Directory of Open Access Journals (Sweden)

    Adam Marek Hamerla

    2015-01-01

    Full Text Available In the paper some aspects of potential use of the Urban River Survey (URS method for hydro-morphological assessment of urban river channels/corridors in Poland are discussed, includingthe URS aspects and criteria. The URS aspects/criteria take into account the specificity of urban watercourse omitted both in the RHS (River Habitat Survey which is more prevalent in Europe, and in Polish MHR method. The URS can be used to classify urban watercourses according to their ecological status, as well as in building scenarios of possible reclamation/restoration activities. The watercourse monitoring with the use of URS can be an important element of the local urban catchment management.

  13. [Principles and methods of mental health resource assessment in military personnel under conditions of demographic crisis].

    Science.gov (United States)

    Vorona, A A; Syrkin, L D

    2011-03-01

    The article is devoted to developing the principles and methods of resource assessment of mental health military contingent in terms of demographic decline and reform of the Armed Forces of the Russian Federation. From the standpoint of the concept of the mutual influence of the value-semantic components and the level of psychological adaptation resources demonstrates the possibility of evaluating resource capabilities of the psyche of military contingent.

  14. Proposed Method for the Verification of the LHC Bus Bar Splices during Commissioning at Cryogenic Conditions

    CERN Document Server

    Calvi, M; Rodríguez-Mateos, F

    2007-01-01

    The commissioning of the Large Hadron Collider at CERN includes the powering of about 1600 superconducting electrical circuits to currents ranging from 55 A to 11.8 kA. A large number of splices (over 70'000) are present at the magnet interconnects, which can only be validated with current at cryogenic conditions. This paper discusses the thermal effects related to possible faulty splices during the powering of the circuits. The calculations of the quench and detection currents, as well as the hot spot temperatures, are described. The heat transfer model with the surrounding coolant and the current profiles inside the splices are presented. This study is completed with a sensitivity analysis on the hot spot temperature with respect to the model parameters. Finally, the implications with respect to the powering ramps and parameters to be applied during the first powering are discussed.

  15. CONDITIONS AND A METHODS OF TRANSPORT OF DANGEROUS GOODS BY AIR

    Directory of Open Access Journals (Sweden)

    Sandra Debeljak Rukavina

    2015-01-01

    Full Text Available The paper shows the international, European and national system of legal rules governing the transport of dangerous goods by air. With the review of the provisions of the Carriage of Dangerous Goods Act and the Final proposal on amendments to this national act, the paper elaborates on the provisions of the Ordinance on the conditions and manner of transport of dangerous goods by air that is in full compliance with Annex 18 to the Convention on International Civil Aviation (“Chicago Convention” - Safe Transport of Dangerous goods by Air, including its amendments, as well as the 2013-2014 Technical instructions Issued and their amendments. A reference is also made to the relevant provisions of Commission Regulation (EU no. 965/2012, which in its Annexes IV and V contains the provisions on the transport of dangerous goods for commercial air transport operations.

  16. Method for Prediction of the Power Output from Photovoltaic Power Plant under Actual Operating Conditions

    Science.gov (United States)

    Obukhov, S. G.; Plotnikov, I. A.; Surzhikova, O. A.; Savkin, K. D.

    2017-04-01

    Solar photovoltaic technology is one of the most rapidly growing renewable sources of electricity that has practical application in various fields of human activity due to its high availability, huge potential and environmental compatibility. The original simulation model of the photovoltaic power plant has been developed to simulate and investigate the plant operating modes under actual operating conditions. The proposed model considers the impact of the external climatic factors on the solar panel energy characteristics that improves accuracy in the power output prediction. The data obtained through the photovoltaic power plant operation simulation enable a well-reasoned choice of the required capacity for storage devices and determination of the rational algorithms to control the energy complex.

  17. System and method for conditioning intake air to an internal combustion engine

    Science.gov (United States)

    Sellnau, Mark C.

    2015-08-04

    A system for conditioning the intake air to an internal combustion engine includes a means to boost the pressure of the intake air to the engine and a liquid cooled charge air cooler disposed between the output of the boost means and the charge air intake of the engine. Valves in the coolant system can be actuated so as to define a first configuration in which engine cooling is performed by coolant circulating in a first coolant loop at one temperature, and charge air cooling is performed by coolant flowing in a second coolant loop at a lower temperature. The valves can be actuated so as to define a second configuration in which coolant that has flowed through the engine can be routed through the charge air cooler. The temperature of intake air to the engine can be controlled over a wide range of engine operation.

  18. Study of the test method for prediction of air conditioning equipment seasonal performance

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, S.B.

    1980-05-01

    The test procedure, Method of Testing, Rating and Estimating the Seasonal Performance of Central Air-Conditioners and Heat Pumps Operating in the Cooling Mode, has been analyzed. The analysis of the test procedure incorporated two main functions: (1) to determine the validity of the test procedure; and (2) to determine if there are other alternate methods of obtaining the same results with less testing burden. Data were collected from industry and analyzed for any significant trends. Certain conclusions are drawn about the energy efficiency ratios, degradation coefficients and seasonal energy efficiency ratios. An error analysis was performed on the test procedure to determine the approximate amount of error when using this procedure. A semi-empirical model assuming a first order system response was developed to determine the factors that affect the part-load and cooling-load factors. The corresponding transient characteristics are then determined in terms of a single time constant. A thermostat demand cycle is used to determine the relationship between on-time and cycle-time. Recommendations are made regarding an alternate method being used to determine the seasonal energy efficiency ratio.

  19. Creation and validation of a novel body condition scoring method for the magellanic penguin (Spheniscus magellanicus) in the zoo setting.

    Science.gov (United States)

    Clements, Julie; Sanchez, Jessica N

    2015-11-01

    This research aims to validate a novel, visual body scoring system created for the Magellanic penguin (Spheniscus magellanicus) suitable for the zoo practitioner. Magellanics go through marked seasonal fluctuations in body mass gains and losses. A standardized multi-variable visual body condition guide may provide a more sensitive and objective assessment tool compared to the previously used single variable method. Accurate body condition scores paired with seasonal weight variation measurements give veterinary and keeper staff a clearer understanding of an individual's nutritional status. San Francisco Zoo staff previously used a nine-point body condition scale based on the classic bird standard of a single point of keel palpation with the bird restrained in hand, with no standard measure of reference assigned to each scoring category. We created a novel, visual body condition scoring system that does not require restraint to assesses subcutaneous fat and muscle at seven body landmarks using illustrations and descriptive terms. The scores range from one, the least robust or under-conditioned, to five, the most robust, or over-conditioned. The ratio of body weight to wing length was used as a "gold standard" index of body condition and compared to both the novel multi-variable and previously used single-variable body condition scores. The novel multi-variable scale showed improved agreement with weight:wing ratio compared to the single-variable scale, demonstrating greater accuracy, and reliability when a trained assessor uses the multi-variable body condition scoring system. Zoo staff may use this tool to manage both the colony and the individual to assist in seasonally appropriate Magellanic penguin nutrition assessment. © 2015 Wiley Periodicals, Inc.

  20. Pavement Condition Assessment Using IRI from Roadroid and Surface Distress Index Method on National Road in Sumenep Regency

    Science.gov (United States)

    Arianto, T.; Suprapto, M.; Syafi’i

    2018-03-01

    The pavement condition will decrease due to the influence of traffic and environment, so that the maintenance effort is needed to maintain the road condition during the service period. In order to carry out road maintenance activities right on target, there needs to be a plan based on accurate pavement condition data. Road roughness is the most commonly used condition parameter in evaluating pavement conditions objectively because road roughness data is relatively easy to obtain, well correlated with vehicle operating costs and the most relevant parameter in road functional performance measurement. The Roadroid is an Android-based application that measures road roughness by using vibration sensors on a smartphone so it is possible to get an International Roughness Index (IRI) value as an indicator of pavement conditions more easily and efficiently. Besides based on road roughness, pavement condition evaluation can also be done visually by using Surface Distress Index (SDI) method that uses the total crack area parameters, average crack width, total number of potholes and the average depth of rutting. This study attempts to assess the condition of Jenderal Sudirman-Kalianget road by combining IRI Roadroid value and SDI value which will be used as the basis to determine the required road maintenance. This road segment is one of the national strategic road connecting the center of Sumenep regency with the Kalianget harbor. Based on IRI measurement and SDI calculation, the pavement condition of Jenderal Sudirman-Kalianget road can be described 4.2 kilometers (37.17%) were good and 2.3 kilometers (20.35%) were fair that need routine maintenance. While 2.1 kilometers (18.58%) were bad and 2.7 kilometers (23.89%) were poor that need periodical maintenance and reconstruction.

  1. A domain-decomposition method to implement electrostatic free boundary conditions in the radial direction for electric discharges

    Science.gov (United States)

    Malagón-Romero, A.; Luque, A.

    2018-04-01

    At high pressure electric discharges typically grow as thin, elongated filaments. In a numerical simulation this large aspect ratio should ideally translate into a narrow, cylindrical computational domain that envelops the discharge as closely as possible. However, the development of the discharge is driven by electrostatic interactions and, if the computational domain is not wide enough, the boundary conditions imposed to the electrostatic potential on the external boundary have a strong effect on the discharge. Most numerical codes circumvent this problem by either using a wide computational domain or by calculating the boundary conditions by integrating the Green's function of an infinite domain. Here we describe an accurate and efficient method to impose free boundary conditions in the radial direction for an elongated electric discharge. To facilitate the use of our method we provide a sample implementation. Finally, we apply the method to solve Poisson's equation in cylindrical coordinates with free boundary conditions in both radial and longitudinal directions. This case is of particular interest for the initial stages of discharges in long gaps or natural discharges in the atmosphere, where it is not practical to extend the simulation volume to be bounded by two electrodes.

  2. Kinetics study of hydrochlorothiazide lactose liquid state interaction using conventional isothermal arrhenius method under basic and neutral conditions

    Directory of Open Access Journals (Sweden)

    Faranak Ghaderi

    Full Text Available ABSTRACT The Maillard reaction of hydrochlorothiazide (HCTZ and lactose has been previously demonstrated in pharmaceutical formulations. In this study, the activation energy of - hydrohlorothiazide and lactose interaction in the liquid state was ascertained under basic and neutral conditions. Conventional isothermal High Performance Liquid Chromatography (HPLC technique was employed to ascertain the kinetic parameters using Arrhenius method. Results: The activation energy obtained was 82.43 and 100.28 kJ/mol under basic and neutral conditions, respectively. Consequently, it can be inferred that Maillard reaction is significantly affected by pH, which can be used as a control factor whenever the reaction potentially occurs.

  3. 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.

  4. On the convergence of the conditional gradient method as applied to the optimization of an elliptic equation

    Science.gov (United States)

    Chernov, A. V.

    2015-02-01

    The optimal control of a second-order semilinear elliptic diffusion-reaction equation is considered. Sufficient conditions for the convergence of the conditional gradient method are obtained without using assumptions (traditional for optimization theory) that ensure the Lipschitz continuity of the objective functional derivative. The total (over the entire set of admissible controls) preservation of solvability, a pointwise estimate of solutions, and the uniqueness of a solution to the homogeneous Dirichlet problem for a controlled elliptic equation are proved as preliminary results, which are of interest on their own.

  5. An automated method for the evaluation of ram libido in real mating conditions.

    Science.gov (United States)

    Alhamada, M; Debus, N; Bocquier, F

    2017-11-01

    We investigated if sexual behaviour of rams can be assessed with an electronic Alpha-Detector (AD) which automatically records mounts of mating rams. To evaluate the rams' libido (i.e. all sexual activities), we used six intact and six vasectomised rams in pen tests in three different seasons (late spring, autumn and early spring). The pen tests consisted of 30-min visual observations of each ram placed in a group of six Merino ewes (three ewes in oestrus and three ewes not in oestrus). In the pen tests, sexual behaviour was recorded and divided into two categories: pre-copulatory and copulatory. For validation purposes, during the pen tests the 12 rams were equipped with the AD and the number of times the 18 oestrous ewes were mounted were counted over a period of 3 days. Of the 1191 mounts visually identified in the six 30-min sessions, 1026 were recorded automatically by the AD (i.e. 94%). The paddock test is an automated method consisting of the same rams wearing an AD and placed in a flock of ~250 Merino ewes on two occasions (late spring (spring 1) and early spring of the following year (spring 2)), their copulatory activities were automatically recorded over a 5-day period. The results of the pen tests in the three seasons revealed no difference between the two types of rams (breeding v. detecting rams). Based on live observations high correlations (r=+0.81, Plibido of the two types of rams measured in pen tests showed high repeatability across the three seasons (83 and 75%, Plibido in paddock tests appears to be more reliable than pen tests and far less time consuming. We therefore recommend this automated method to estimate the libido of rams. In addition, this method can be used at any season of the year provided that ewes in oestrus are present in the flock.

  6. Pressure Retarded Osmosis and Forward Osmosis Membranes: Materials and Methods

    Directory of Open Access Journals (Sweden)

    May-Britt Hägg

    2013-03-01

    Full Text Available In the past four decades, membrane development has occurred based on the demand in pressure driven processes. However, in the last decade, the interest in osmotically driven processes, such as forward osmosis (FO and pressure retarded osmosis (PRO, has increased. The preparation of customized membranes is essential for the development of these technologies. Recently, several very promising membrane preparation methods for FO/PRO applications have emerged. Preparation of thin film composite (TFC membranes with a customized polysulfone (PSf support, electorspun support, TFC membranes on hydrophilic support and hollow fiber membranes have been reported for FO/PRO applications. These novel methods allow the use of other materials than the traditional asymmetric cellulose acetate (CA membranes and TFC polyamide/polysulfone membranes. This review provides an outline of the membrane requirements for FO/PRO and the new methods and materials in membrane preparation.

  7. Optical Camouflage Effect Objective Evaluation Method Research Under The Condition of Complex Backgrounds

    Directory of Open Access Journals (Sweden)

    Qin Jianfei

    2016-01-01

    Full Text Available According to the problem that the intelligence is not high of the soccer robot, using the mechanical theory as a guide, making some mechanical analyses and calculations on the pressure and transmutation states of chip kick mechanics, and conducting optimal design too, then making the structure of chip kick mechanics more and more rationalization. Experiments show that the new soccer robot controller features a quick response and high servo rigidity, and provide a kind of method for improving and perfecting the soccer robot control system, at the same time, filling the needs of producing

  8. A highly precise frequency-based method for estimating the tension of an inclined cable with unknown boundary conditions

    Science.gov (United States)

    Ma, Lin

    2017-11-01

    This paper develops a method for precisely determining the tension of an inclined cable with unknown boundary conditions. First, the nonlinear motion equation of an inclined cable is derived, and a numerical model of the motion of the cable is proposed using the finite difference method. The proposed numerical model includes the sag-extensibility, flexural stiffness, inclination angle and rotational stiffness at two ends of the cable. Second, the influence of the dynamic parameters of the cable on its frequencies is discussed in detail, and a method for precisely determining the tension of an inclined cable is proposed based on the derivatives of the eigenvalues of the matrices. Finally, a multiparameter identification method is developed that can simultaneously identify multiple parameters, including the rotational stiffness at two ends. This scheme is applicable to inclined cables with varying sag, varying flexural stiffness and unknown boundary conditions. Numerical examples indicate that the method provides good precision. Because the parameters of cables other than tension (e.g., the flexural stiffness and rotational stiffness at the ends) are not accurately known in practical engineering, the multiparameter identification method could further improve the accuracy of cable tension measurements.

  9. Method for determining optimal intracavitary radiotherapy conditions for carcinoma of the uterine cervix with tumor infiltration of the vaginal wall

    International Nuclear Information System (INIS)

    Tabushi, Katsuyoshi; Obata, Yasunori; Itoh, Susumu; Sakura, Mizuyoshi; Kato, Singo; Kazumoto, Tomoko; Nakamura, Yuzuru; Iinuma, T.A.; Arai, Tatsuo.

    1997-01-01

    Stage III carcinoma of the uterine cervix is occasionally accompanied by tumor infiltration of the vaginal wall. Currently, the vaginal wall has to be irradiated in the same manner as the uterine cervix. The authors have developed a system for determining the optimal irradiation conditions for treating the two regions, uterine cervix and vaginal wall, at the same time. A comparison of two methods is shown in simulation, and then a clinical case is reported. The first method consists of two treatment plans, one for the uterine cervix without tumor infiltration of the vaginal wall, and the other for the vaginal wall without carcinoma of the uterine cervix. The second, newly developed method considers the two regions together. Irradiation times of ovoid sources obtained with the second method are 15-25% less than those of the first method. Isodose curves obtained with the two methods are very different and thus the uterine cervix and vaginal wall must be considered together in order to determine irradiation conditions. (author)

  10. A comparison of alternative methods to compute conditional genotype probabilities for genetic evaluation with finite locus models

    Directory of Open Access Journals (Sweden)

    Dekkers Jack CM

    2003-11-01

    Full Text Available Abstract An increased availability of genotypes at marker loci has prompted the development of models that include the effect of individual genes. Selection based on these models is known as marker-assisted selection (MAS. MAS is known to be efficient especially for traits that have low heritability and non-additive gene action. BLUP methodology under non-additive gene action is not feasible for large inbred or crossbred pedigrees. It is easy to incorporate non-additive gene action in a finite locus model. Under such a model, the unobservable genotypic values can be predicted using the conditional mean of the genotypic values given the data. To compute this conditional mean, conditional genotype probabilities must be computed. In this study these probabilities were computed using iterative peeling, and three Markov chain Monte Carlo (MCMC methods – scalar Gibbs, blocking Gibbs, and a sampler that combines the Elston Stewart algorithm with iterative peeling (ESIP. The performance of these four methods was assessed using simulated data. For pedigrees with loops, iterative peeling fails to provide accurate genotype probability estimates for some pedigree members. Also, computing time is exponentially related to the number of loci in the model. For MCMC methods, a linear relationship can be maintained by sampling genotypes one locus at a time. Out of the three MCMC methods considered, ESIP, performed the best while scalar Gibbs performed the worst.

  11. Development of a Complex Geometry Standard Fixture and Solvent Evaluation Method fo Assessing Replacement Solvents for AK-225G

    Data.gov (United States)

    National Aeronautics and Space Administration — Environmental regulatory requirements dictate the need for NASA Stennis, and NASA as a whole to identify new solvents that conform to changing environmental impact...

  12. Methods of dilatometric investigations under extreme conditions and the case of spin-ice compounds

    Science.gov (United States)

    Doerr, M.; Granovsky, S.; Rotter, M.; Stöter, T.; Wang, Z.-S.; Zherlitsyn, S.; Wosnitza, J.

    2017-10-01

    We give an overview on how dilatometric methods have been developed in the last decade. The concept of capacitive dilatometry was successfully adapted to dilution refrigerators with a resolution of 10-9. Miniaturized dilatometers with an overall diameter of 18 mm or less are optimally suited for measuring longitudinal and transversal components of the striction tensor. Going to another extreme, to the highest (pulsed) fields, optical methods, such as the FBG technology, were developed for investigations up to 100 T. As examples for utilizing dilatometry at low temperatures we show results for the spin-ice materials Dy2Ti2O7 and Ho2Ti2O7. To characterise the magneto-elastic coupling in these materials, we investigated the thermal expansion and magnetostriction between 80 mK and 15 K and in magnetic fields aligned along the [111] direction and found field-induced phases and strong correlations below 500 mK. Our data demonstrate, that the formation of the field-induced phase is strongly influenced by lattice distortions: any change in interatomic distances will result in a variation of the exchange couplings.

  13. A Differential Evolution Based MPPT Method for Photovoltaic Modules under Partial Shading Conditions

    Directory of Open Access Journals (Sweden)

    Kok Soon Tey

    2014-01-01

    Full Text Available Partially shaded photovoltaic (PV modules have multiple peaks in the power-voltage (P-V characteristic curve and conventional maximum power point tracking (MPPT algorithm, such as perturbation and observation (P&O, which is unable to track the global maximum power point (GMPP accurately due to its localized search space. Therefore, this paper proposes a differential evolution (DE based optimization algorithm to provide the globalized search space to track the GMPP. The direction of mutation in the DE algorithm is modified to ensure that the mutation always converges to the best solution among all the particles in the generation. This helps to provide the rapid convergence of the algorithm. Simulation of the proposed PV system is carried out in PSIM and the results are compared to P&O algorithm. In the hardware implementation, a high step-up DC-DC converter is employed to verify the proposed algorithm experimentally on partial shading conditions, load variation, and solar intensity variation. The experimental results show that the proposed algorithm is able to converge to the GMPP within 1.2 seconds with higher efficiency than P&O.

  14. Methods of Assessment of Variants of Technical and Technological Renovation under Modern Conditions

    Directory of Open Access Journals (Sweden)

    Shevchuk Larysa M.

    2013-11-01

    Full Text Available The article marks out stages of planning of the moment of renovation, considers an algorithm of selection of the best variant of renovation out of alternative variants with consideration of such aspects as the degree of risk of each investment project, financial capabilities and economic efficiency of renovation. The article studies the scheme of analysis of alternative variants of technical and technological renovation, which includes preliminary, financial and economic, technical and other types of analysis. The article forms an economic model of assessment of introduction of a new technology at an enterprise moving by the technological scheme of development and realisation of novelty; it calculates expenses (engineering and design, material, technical and personnel training costs and identifies economic possibilities of an enterprise on the conduct of renovation. In the result it allocates the indicator of realisation of a new technology in general by an aggregate group of factors. Due to absence of indicators of assessment of efficiency of renovation adapted to market conditions, the article offers to calculate the indicator of assessment of efficiency of investing into renovation, showing what portion of the investment is returned in the form of profit during one period of planning.

  15. A simple degradation method for sulfur mustard at ambient conditions using nickelphthalocyanine incorporated polypyrrole modified electrode

    Science.gov (United States)

    Sharma, Pushpendra K.; Sikarwar, Bhavna; Gupta, Garima; Nigam, Anil K.; Tripathi, Brijesh K.; Pandey, Pratibha; Boopathi, Mannan; Ganesan, Kumaran; Singh, Beer

    2014-01-01

    Electrocatalytic degradation of sulfur mustard (SM) was studied using a gold electrode modified with nickelphthalocyanine and polypyrrole (NiPc/pPy/Au) in the presence of a cationic surfactant cetyltrimethyl ammonium bromide. Several techniques such as cyclic voltammetry, scanning electron microscopy, electrochemical impedance spectroscopy, energy dispersive X-ray spectroscopy and Raman spectroscopy have been employed for the characterization of modified electrodes. NiPc/pPy/Au modified electrode exhibited excellent electrochemical sensing and degradation ability towards SM. The present modification indicated two electron involvements in the electrocatalytic degradation of SM in addition to being an irreversible adsorption controlled process. Degraded products were identified by gas chromatography-mass spectrometry. Moreover, electrochemical parameters of oxidation of SM such as heterogeneous rate constant (0.436 s-1), transfer coefficient (0.47) and the number of electrons involved (2) were deduced from cyclic voltammetry results. The NiPc/pPy/Au modified electrode showed excellent electrocatalytic degradation towards SM when compared to bare gold, pPy/Au and NiPc/Au modified electrode at ambient conditions.

  16. D0 Silicon Upgrade: Calculating Mass Flow Rates at Sub-Sonic Conditions Trhough Venturis (FT-4052-H & FT-4053-H) and an Orifice Plate (F)-2019-H)

    Energy Technology Data Exchange (ETDEWEB)

    Zaczek, Mauiusz; /Fermilab

    1996-08-15

    The purpose of this engineering note is to explain the method involved in calculating the mass flow rates through venturis and orifice plates at sub-sonic conditions. In particular, the mass flow rate calculations are required for two FLOW-DYNE venturi flow meters, serial no. 35821 and no. 35822, and an orifice plate flow meter, serial no. 35823. The two venturis, FT-4052-H and FT-4053-H, are located in the D-Zero VLPC valve box at the refrigerator and the orifice plate, FO-2019-H, is on the high pressure helium supply line in the assembly building.

  17. Evaluation of two methods DNA extraction from formalin-fixed, paraffin-embedded tissues on non-optimal conditions

    International Nuclear Information System (INIS)

    Bustamante, Javier Andres; Astudillo, Miryam; Pazos, Alvaro Jairo; Bravo, Luis Eduardo

    2011-01-01

    Paraffin wax embedded tissues are an invaluable material for retrospective studies requiring the application of molecular analysis. Multiple methods are available to extract DNA from these kinds of samples. However, the most common methods are slow and the reagents often contribute to the fragmentation of genetic material. In order to optimize the procedure, two methods for DNA extraction from paraffin embedded tissue non-optimal conditions were used. 47 blocks containing paraffin-embedded biopsies of pleura, lung and pericardium from 24 patients (66.6% males) older than 18 years, with biopsy proven chronic granulomatous inflammation referred to the department of pathology at University Hospital of Valle between 2002 and 2007 were selected. Each sample was subjected to 10 cuts and was to two methods of DNA extraction: 1. conventional and 2. QIAamp - DNA mini kit. The efficiency of the extracted DNA was assessed by spectrophotometry and PCR amplification of a fragment of the housekeeping gene GAPDH. The concentration of DNA samples extracted by the conventional method was of 65.52 ng/Mu l ± 11.47 (mean ± SE) and the 260/280 absorbance ratio ranged between 0.52 and 2.30 the average concentration of DNA of the samples extracted by the commercial method was 60.89 ng/Mu l ± 6.02 (mean ± SE), with an absorbance that fluctuated between 0 and 2.64. The DNA obtained was amplified by PCR, of 47 samples extracted by methods, 25 and 23 respectively the GAPDH gene amplified successfully. The methods used to obtain DNA showed similar performance, highlighting the potential utility of both extraction methods for the retrospective studies from paraffin embedded tissues in unsuitable conditions.

  18. Monitoring thermal processes in low-permeability fractured media using fibre-optics distributed temperature sensing (FO-DTS)

    Science.gov (United States)

    Brixel, Bernard; Klepikova, Maria; Jalali, Mohammadreza; Loew, Simon; Amann, Florian

    2017-04-01

    Fibre-optics distributed temperature sensing (FO-DTS) systems constitute arguably one of the main significant advances in the development of modern monitoring techniques in field hydrogeology, both for shallow (e.g. quantification of surface water-groundwater interactions) and deeper applications (borehole temperature monitoring). Deployment of FO-DTS monitoring systems in boreholes has notably allowed further promoting the use of temperature as a tracer to improve the characterization of heterogeneous media, with a strong focus on permeable environments such as shallow unconsolidated aquifers and/or highly-fractured rocks, generally found close to ground surface. However, applying this technology to low-permeability media, as in the case of intact rock mass intersected by isolated, discrete fractures still remains a challenge, perhaps explaining the limited number of field results reported in the scientific literature to date. Yet, understanding the transport, storage and exchange of heat in deep, low-permeability crystalline rocks is critical to many scientific and engineering research topics and applications, including for example deep geothermal energy (DGE). In the present contribution, we describe the use and application of FO-DTS monitoring to a broad range of processes, varying from the propagation and persistence of thermal anomalies (both natural and induced) to the monitoring of the curing of epoxy resin and cement grouts along the annular space of boreholes designed for monitoring discrete, packed-off zones. All data provided herein has been collected as part of a multi-disciplinary research program on hydraulic stimulation and deep geothermal energy carried out at the Grimsel Test Site (GTS), an underground rock laboratory located in the Aar massif, in the Swiss Alps. Through these examples, we illustrate the importance of understanding the spatial and temporal variations of local thermal regimes when planning to monitoring boreholes temperatures

  19. Periodic boundary conditions and the error-controlled fast multipole method

    Energy Technology Data Exchange (ETDEWEB)

    Kabadshow, Ivo

    2012-08-22

    The simulation of pairwise interactions in huge particle ensembles is a vital issue in scientific research. Especially the calculation of long-range interactions poses limitations to the system size, since these interactions scale quadratically with the number of particles. Fast summation techniques like the Fast Multipole Method (FMM) can help to reduce the complexity to O(N). This work extends the possible range of applications of the FMM to periodic systems in one, two and three dimensions with one unique approach. Together with a tight error control, this contribution enables the simulation of periodic particle systems for different applications without the need to know and tune the FMM specific parameters. The implemented error control scheme automatically optimizes the parameters to obtain an approximation for the minimal runtime for a given energy error bound.

  20. Quality of weld clads applied by SAW method in adhesive wear conditions

    Directory of Open Access Journals (Sweden)

    Janette Brezinová

    2012-11-01

    Full Text Available This contribution deals with the analysis of the renovation layer quality of continuous casting steel rolls, developed through the submerged arc surfacing method (SAW. The continuous casting roll was analysed via the degradation phenomena which act during the operation. Four kinds of filler materials were used for the renovation of the worn roll. Surfacing was carried out as a three-layer in order to eliminate the need for intermediate layer formation. The quality of weld deposits was evaluated in terms of the structure, hardness and wear resistance of weld deposits at 23°C and 400 °C using pin-on-disc wear test. The best properties showed newly developed filler material W8-WLDC8 from the point of view of the hardness, together with wear resistance of the deposited layers in room and elevated temperatures.

  1. Laser Based In Situ Techniques: Novel Methods for Generating Extreme Conditions in TEM Samples

    Energy Technology Data Exchange (ETDEWEB)

    Taheri, M; Lagrange, T; Reed, B; Armstrong, M; Campbell, G; DeHope, W; Kim, J; King, W; Masiel, D; Browning, N

    2008-02-25

    The Dynamic Transmission Electron Microscope (DTEM) is introduced as a novel tool for in situ processing of materials. Examples of various types of dynamic studies outline the advantages and differences of laser-based heating in the DTEM in comparison to conventional (resistive) heating in situ TEM methods. We demonstrate various unique capabilities of the drive laser, namely, in situ processing of nanoscale materials, rapid and high temperature phase transformations, and controlled thermal activation of materials. These experiments would otherwise be impossible without the use of the DTEM drive laser. Thus, the potential of the DTEM to as a new technique to process and characterize the growth of a myriad of micro and nanostructures is demonstrated.

  2. Investigation of porous silicon obtained under different conditions by the contact angle method

    Science.gov (United States)

    Belorus, A. O.; Bukina, Y. V.; Pastukhov, A. I.; Stebko, D. S.; Spivak, Yu M.; Moshnikov, V. A.

    2017-11-01

    This paper investigates a hydrophobicity/hydrophilicity of porous silicon by the contact angle method. Porous silicon series were obtained by electrochemical anodic etching of n-Si (100) and (111) under the current anodization density range of 5-120 mA/cm2. For this purpose the original laboratory installation and the software «Measurement of contact angle» were developed. It is shown that, the contact angle can vary significantly (up to 80 degrees for (100)) depending on the current anodization Discussion of the results is carried out taking in account the composition of the functional groups and of surface morphology of the porous silicon. These results are important for developing porous silicon particles as nanocontainers in the targeted drug delivery.

  3. ASSESSMENT OF BONE TISSUE CONDITION BY METHOD OF COMPUTED TOMOGRAPHY IN PTS WITH RHEUMATOID ARTHRITIS

    Directory of Open Access Journals (Sweden)

    T A Raskina

    2002-01-01

    Full Text Available Aim: To estimate the bone mineral density (BMD in patients with dilVerent variants of rheumatoid arthritis (RA. Materials and methods: The study included 65 patients with the acknowledged RA, who were not treated with corticosteroids, basic remedies and antiosteoporosis therapies. The group comprises 26 women оГ reproductive age (I group and 28 women in postmenopause period. The investigations were held with the computer tomograph “Tomoscan” Philips. Results: The comparative analysis of BMD disorders frequency in the studied groups shows that in RA women of postmenopause period osteopenia accounts for 57,1%, osteoporosis - for 32,1% of patients, which is twice as often as in premenopausal women period: 30,8% and 15,4% respectively. BMD levels in RA are correlated with rheumatoid lactor, destructive tendency in bones and high activity of disease.

  4. METHOD OF NON-CONTACT PHOTOLUMINESCENT DIAGNOSTICS OF THE EYE FIBROUS TUNIC CONDITION

    Directory of Open Access Journals (Sweden)

    S. Yu. Petrov

    2018-01-01

    Full Text Available Non-contact optical diagnostics of structural disorders of the eye has a number of advantages: high speed, accuracy and a large range of parameters available for analysis. The paper presents the results of studies of the photoluminescence of the fibrous tunic of the eye, excited by polarized light, depending on the intraocular pressure. In the experiments, isolated de-epithelized eyes of the rabbit were used, inside of which pressure up to 50 mm Hg was artificially created. Under these conditions, the cornea and sclera were illuminated with linearly polarized light at wavelengths of 250, 350 and 450 nm, exciting photoluminescence in the wavelength range up to 700 nm. Cross and co-polarized photoluminescence spectra excited by linearly polarized light were obtained. It has been established that, when excited by polarized light, the photoluminescence of the cornea is partially polarized. Depending on the wavelength of the photoluminescence, the degree of polarization varies from 0.2 to 0.35. It is shown that the degree of polarization of the photoluminescence of the cornea of the eye upon excitation by linearly polarized light can be used as a measurable parameter for assessing the physiological state of the eye. It is shown that the photoluminescence spectrum consists of two bands with maxima near 460-470 and 430-440 nm. These bands are assigned, respectively, to pyridinnucleotides and glycosylated collagen. A significant contribution can be made by the epithelium of the eye, which contains riboflavin with characteristic absorption bands near 450 and 365 nm. When excited at 450 nm, the photoluminescence maximum is located near 540 nm, which corresponds to the spectrum of fluorophores in the endothelium and epithelium. The spectrum of photoluminescence upon excitation at a wavelength of 250 nm can be attributed to tryptophan located in the intraocular lens.

  5. Digitalt interaktivt läromedel för nya användare genom text och bild i samverkan

    OpenAIRE

    Öhlin, Anna

    2017-01-01

    Utgångspunkten i det här arbetet var att studera hur ett digitalt interaktivt läromedel för nya användare kan utformas genom text och bild i samverkan. Arbetet gjordes i uppdrag av Eskilstuna kommun med syftet att informera min målgrupp om Geografiska informationssystem (GIS). Den primära målgruppen för det här arbetet är anställa i Eskilstuna kommun som är nya användare av GIS. GIS är digitala kartor i 2D eller 3D som kan användas för insamling, lagring, analysering och pres...

  6. Analysis of Waveguide Devices Involving Lateral and Transverse Perfect Magnetic Wall Boundary Conditions by the Mode-Matching Method

    Science.gov (United States)

    Polo-López, Lucas; Ruiz-Cruz, Jorge A.; Montejo-Garai, José R.; Rebollar, Jesús M.

    2017-09-01

    This contribution presents the analysis of waveguide problems involving general boundary conditions of perfect magnetic wall. This type of boundary condition is used in electromagnetic solvers very commonly when the device under analysis has physical symmetry, in order to speed up the computation time. This paper is focused on extending its use in problems having this type of boundary condition in the lateral and transverse walls of the waveguides involved in the problem. The presented formulation, based on the mode-matching method, will be applied to classical waveguide devices, but also to address radiating problems with a novel formulation. Different applications will be targeted, and the simulation results will be compared with those obtained by other numerical techniques (based on different solvers), validating the presented approach as another suitable tool for computer-aided design.

  7. Current status of NO{sub x} prediction by conditional moment closure method for turbulent non premixed flames

    Energy Technology Data Exchange (ETDEWEB)

    Huh, K.Y. [Pohang Univ. of Science and Technology, Pohang, (Korea, Republic of). Dept. of Mechanical Engineering

    2005-07-01

    Nitrogen oxides (NO{sub x}) are one of the most strictly regulated atmospheric pollutants originating from industrial and automotive combustion processes, and the development of an accurate prediction method has become an urgent research goal in both academic and engineering communities. NO{sub x} emissions are sensitive to most design parameters and operating conditions of combustion devices, since they are controlled by both chemical kinesis and turbulent mixing. This paper presented a summary of the current status of NO{sub x} prediction by the conditional moment closure (CMC) method, as well as details of experiments conducted to validate the CMC method. Recent validation results of first and second order CMC were discussed. It was suggested that given proper information on mixture composition and boundary conditions, it is possible to make accurate predictions of NO{sub x} employing detailed chemical kinetic mechanisms for hydrocarbon oxidation and NO{sub x}, even in extreme cases with significant local extinction. Four test flames were analyzed in this experiment: piloted jet, simple jet, MILD combustion, and bluffbody flames. Results indicate that first order closure is accurate enough for most flames not far from equilibrium, while significant improvements can be made near ignition or extinction limits by second-order closure. The CMC method can be applied to predict NO{sub x} emission in many practical combustion systems involving complicated flow fields. Details of mixing calculations and turbulence models were discussed along with issues concerning flame structure determined by chemistry and scalar dissipation. It was concluded that the CMC method is more accurate than approaches based on unconditional averaging, and computationally more efficient than other transport methods. 15 refs., 6 figs.

  8. An inverse method for calculation of thermal inertia and heat gain in air conditioning and refrigeration systems

    International Nuclear Information System (INIS)

    Fayazbakhsh, M.A.; Bagheri, F.; Bahrami, M.

    2015-01-01

    Highlights: • An inverse method is proposed to calculate thermal inertia in HVAC-R systems. • Real-time thermal loads are estimated using the proposed intelligent algorithm. • Calculation algorithm is validated with on-site measurements. • Freezer duty cycle data are extracted only based on temperature measurements. - Abstract: A new inverse method is proposed for estimation of thermal inertia and heat gain in air conditioning and refrigeration systems using on-site temperature measurements. The method is applied on a walk-in freezer room of a restaurant in Surrey, British Columbia, Canada during one week of its regular operation. The thermal inertia and instantaneous heat gain are calculated and the results are validated using actual information of the materials inside the freezer room. The proposed method can be implemented in intelligent control systems designed for new and existing HVAC-R systems to improve their overall energy efficiency and reduce their environmental impacts

  9. Methods for quantifying the influences of pressure and temperature variation on metal hydride reaction rates measured under isochoric conditions.

    Science.gov (United States)

    Voskuilen, Tyler G; Pourpoint, Timothée L

    2013-11-01

    Analysis techniques for determining gas-solid reaction rates from gas sorption measurements obtained under non-constant pressure and temperature conditions often neglect temporal variations in these quantities. Depending on the materials in question, this can lead to significant variations in the measured reaction rates. In this work, we present two new analysis techniques for comparison between various kinetic models and isochoric gas measurement data obtained under varying temperature and pressure conditions in a high pressure Sievert system. We introduce the integral pressure dependence method and the temperature dependence factor as means of correcting for experimental variations, improving model-measurement fidelity, and quantifying the effect that such variations can have on measured reaction rates. We use measurements of hydrogen absorption in LaNi5 and TiCrMn to demonstrate the effect of each of these methods and show that their use can provide quantitative improvements in interpretation of kinetics measurements.

  10. [Technological process of cell disruption for extracting astaxanthin from Phaffia rhodozyma by acid method under autoclave conditions].

    Science.gov (United States)

    Lu, Baoju; Xiao, Anfeng; Lil, Lijun; Ni, Hui; Cai, Huinong; Su, Wenjin

    2008-07-01

    Phaffia rhodozyma is one of the organisms for production of astaxanthin, and the key process for extracting intracellular astaxanthin is cell disruption. In this work, cell disruption for extracting astaxanthin from Phaffia rhodozyma was studied with autoclave method at low acid concentration. The optimum disrupting conditions were: autoclave pressure 0.1 MPa, 121 degrees C; hydrochloric acid concentration 0.5 mol/L; liquid to material ratio (V/W) 30 mL/g dry cell weight and disruption time 2 min. Under the optimum conditions, medium scale experiment showed that astaxanthin and total carotenoids recovery from Phaffia rhodozyma were (84.8 +/- 3.2)% and (93.3 +/- 2)%, respectively. This new method can lead to no poisonous residues and get high extraction yield, which have good prospects to be put into industrial production.

  11. Determination of the ejector dimensions of a bus air-conditioning system using analytical and numerical methods

    International Nuclear Information System (INIS)

    Ünal, Şaban

    2015-01-01

    Comfortable journey with commercial buses is an essential goal of transportation companies. An air-conditioning system can play an important role for this comfortable journey but it can put extra load on the engine and extra cost in the fuel consumption. The purpose of this work is to increase the performance of air-conditioning system of the buses by reducing the load on the engine and fuel consumption. Using a two-phase ejector as an expansion valve can increase the coefficient of performance (COP) of the air-conditioning system. An improvement in the COP can reduce the empty vehicle weight and fuel consumption of buses. Two-phase ejector dimensions can be determined using the empirical methods available in the literature. In this paper, the two-phase ejector dimensions of air conditioning system for a bus are calculated using the analytical and numerical methods. First of all, the thermodynamic analysis of the vapor-compression refrigeration cycle with a two-phase ejector is performed, and then the ejector dimensions are subsequently determined. The cooling loads of the midibus and bus with R134a as a refrigerant are assumed to be 14 kW and 32 kW, respectively. The total length of the two-phase ejector for the midibuses and buses due to these cooling loads, are computed to be 480.8 mm and 793.1 mm, respectively. Also, an experimental setup is installed on a midibus air conditioner to turn it into the ejector air conditioning system to validate theoretical results with the experimental study. - Highlights: • Determination of two-phase ejector dimensions of a bus air-conditioning system. • Thermodynamic analysis of the two-phase ejector cooling system. • Experimental study on a midibus air conditioner using two-phase ejector.

  12. Culture condition improvement for whole-cell lipase production in submerged fermentation by Rhizopus chinensis using statistical method.

    Science.gov (United States)

    Teng, Yun; Xu, Yan

    2008-06-01

    Rhizopus chinensis CCTCC M201021 was a versatile strain capable of producing whole-cell lipase with synthetic activity in submerged fermentation. In order to improve the production of whole-cell lipase and study the culture conditions systematically, the combination of taguchi method and response surface methodology was performed. Taguchi method was used for the initial optimization, and eight factors viz., maltose, olive oil, peptone, K2HPO4, agitation, inoculum size, fermentation volume and pH were selected for this study. The whole-cell lipase activity yield was two times higher than the control experiment under initial optimal conditions, and four significant factors (inoculum, olive oil, fermentation volume and peptone) were selected to test the effect on the lipase production using response surface methodology. The optimal fermentation parameters for enhanced whole-cell lipase yield were found to be: inoculum 4.25 x 10(8) spores/L, olive oil 2.367% (w/v), fermentation volume 18 mL/250 mL flask, peptone 4.06% (w/v). Subsequent experimental trails confirmed the validity of the model. These optimal culture conditions in the shake flask led to a lipase yield of 13875 U/L, which 120% increased compare with the non-optimized conditions.

  13. ATPaseTb2, a unique membrane-bound FoF1-ATPase component, is essential in bloodstream and dyskinetoplastic trypanosomes.

    Directory of Open Access Journals (Sweden)

    Karolína Šubrtová

    2015-02-01

    Full Text Available In the infectious stage of Trypanosoma brucei, an important parasite of humans and livestock, the mitochondrial (mt membrane potential (Δψm is uniquely maintained by the ATP hydrolytic activity and subsequent proton pumping of the essential FoF1-ATPase. Intriguingly, this multiprotein complex contains several trypanosome-specific subunits of unknown function. Here, we demonstrate that one of the largest novel subunits, ATPaseTb2, is membrane-bound and localizes with monomeric and multimeric assemblies of the FoF1-ATPase. Moreover, RNAi silencing of ATPaseTb2 quickly leads to a significant decrease of the Δψm that manifests as a decreased growth phenotype, indicating that the FoF1-ATPase is impaired. To further explore the function of this protein, we employed a trypanosoma strain that lacks mtDNA (dyskinetoplastic, Dk and thus subunit a, an essential component of the proton pore in the membrane Fo-moiety. These Dk cells generate the Δψm by combining the hydrolytic activity of the matrix-facing F1-ATPase and the electrogenic exchange of ATP4- for ADP3- by the ATP/ADP carrier (AAC. Surprisingly, in addition to the expected presence of F1-ATPase, the monomeric and multimeric FoF1-ATPase complexes were identified. In fact, the immunoprecipitation of a F1-ATPase subunit demonstrated that ATPaseTb2 was a component of these complexes. Furthermore, RNAi studies established that the membrane-bound ATPaseTb2 subunit is essential for maintaining normal growth and the Δψm of Dk cells. Thus, even in the absence of subunit a, a portion of the FoF1-ATPase is assembled in Dk cells.

  14. Testing Local Conditions for the Introduction of a Mercury-free Gold Extraction Method using Borax in Zimbabwe

    OpenAIRE

    Nadine Steckling; Stephan Bose-O’Reilly; Dennis Shoko; Stefan Muschack; Rudolf Schierl

    2014-01-01

    Background. Mercury is extensively used in artisanal small-scale gold mining in many parts of the world, including Zimbabwe. Mercury-free mining technologies are urgently needed to protect the biophysical environment and human health. Objective. The testing of local conditions for the introduction of a mercury-free gold mining technology entailing the use of borax in a field project in Kadoma/Zimbabwe. Materials and Methods. A one-day theoretical workshop and a two-day practical demonst...

  15. Synthesis-condition dependence of carbon nanotube growth by alcohol catalytic chemical vapor deposition method

    Directory of Open Access Journals (Sweden)

    Nobuhito Inami et al

    2007-01-01

    Full Text Available We report the dependence of growth yield of single-walled carbon nanotubes (SWNTs on heat-treatment time and catalyst film thickness by the alcohol catalytic chemical vapor deposition method. Three types of heat-treatment, synthesis of 30 min, synthesis of 30 min after annealing of 30 min, and synthesis of 60 min, were investigated. Thickness of Co catalyst film was varied from 1 to 10 nm. In the case of thinner Co film less than 3 nm, long synthesis time of 60 min is favorable for the effective SWNT growth, because of the small amount of Co catalyst. In the case of thicker Co film more than 3 nm, an amount of grown SWNTs by 30 min synthesis after 30 min annealing and by 60 min synthesis was much higher than that by 30 min synthesis without annealing, showing that total heat-treatment time of 60 min is important for the SWNT growth. Results suggest that the conversion from the thicker film of Co to nano-particle which acts as catalyst takes place during the first 30 min.

  16. Methods of inducing conditioned food aversion to Baccharis coridifolia (mio-mio in cattle

    Directory of Open Access Journals (Sweden)

    Milton Begeres de Almeida

    2013-10-01

    Full Text Available Three experiments were performed to determine the efficacy of various methods of averting naïve cattle to prevent Baccharis coridifolia poisoning: forced oral administration of 0.5g kg-1 body weight of fresh B. coridifolia; forced inhalation of the smoke from burning B. coridifolia and rubbing the plant on the animals' muzzles and mouths; and introducing the animals into paddocks with low invasion by B. coridifolia. Results demonstrated that cattle forced to ingest low doses become strongly averted if introduced into paddocks 23-26 hours after the aversion. In contrast, cattle introduced into the paddocks between 1-10 hours were not fully averted. Inhalation of B. coridifolia smoke, and rubbing the plant on the animals' muzzles and mouths were not efficient to induce an aversion. The introduction of cattle into paddocks with approximately 1% of B. coridifolia was efficient if the animals remained 5 months in the area, but not if they only remained for 60 hours, as cattle required sufficient time to learn to avoid the plant.

  17. Motion-blurred star acquisition method of the star tracker under high dynamic conditions.

    Science.gov (United States)

    Sun, Ting; Xing, Fei; You, Zheng; Wei, Minsong

    2013-08-26

    The star tracker is one of the most promising attitude measurement devices used in spacecraft due to its extremely high accuracy. However, high dynamic performance is still one of its constraints. Smearing appears, making it more difficult to distinguish the energy dispersive star point from the noise. An effective star acquisition approach for motion-blurred star image is proposed in this work. The correlation filter and mathematical morphology algorithm is combined to enhance the signal energy and evaluate slowly varying background noise. The star point can be separated from most types of noise in this manner, making extraction and recognition easier. Partial image differentiation is then utilized to obtain the motion parameters from only one image of the star tracker based on the above process. Considering the motion model, the reference window is adopted to perform centroid determination. Star acquisition results of real on-orbit star images and laboratory validation experiments demonstrate that the method described in this work is effective and the dynamic performance of the star tracker could be improved along with more identified stars and guaranteed position accuracy of the star point.

  18. Standard test method for determination of resistance to stable crack extension under low-constraint conditions

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 This standard covers the determination of the resistance to stable crack extension in metallic materials in terms of the critical crack-tip-opening angle (CTOAc), ψc and/or the crack-opening displacement (COD), δ5 resistance curve (1). This method applies specifically to fatigue pre-cracked specimens that exhibit low constraint (crack-length-to-thickness and un-cracked ligament-to-thickness ratios greater than or equal to 4) and that are tested under slowly increasing remote applied displacement. The recommended specimens are the compact-tension, C(T), and middle-crack-tension, M(T), specimens. The fracture resistance determined in accordance with this standard is measured as ψc (critical CTOA value) and/or δ5 (critical COD resistance curve) as a function of crack extension. Both fracture resistance parameters are characterized using either a single-specimen or multiple-specimen procedures. These fracture quantities are determined under the opening mode (Mode I) of loading. Influences of environment a...

  19. Effect of synthesis conditions on the preparation of YIG powders via co-precipitation method

    International Nuclear Information System (INIS)

    Rashad, M.M.; Hessien, M.M.; El-Midany, A.; Ibrahim, I.A.

    2009-01-01

    Yttrium iron garnet (YIG) (Y 3 Fe 5 O 12 ) powders have been synthesized through a co-precipitation method in the presence of sodium bis(2-ethylhexylsulfosuccinate), AOT as an anionic surfactant. The garnet precursors produced were obtained from aqueous iron and yttrium nitrates mixtures using 5 M sodium hydroxide at pH 10. A statistical Box-Behnken experimental design was used to investigate the effect of the main parameters (i.e. AOT surfactant concentration, annealing time and temperature) on YIG powder formation, crystallite size, morphology and magnetic properties. YIG particles were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer. XRD revealed that the formation of single cubic phase of YIG was temperature dependent and increased by increasing the annealing temperature from 800 to 1200 o C. SEM micrographs showed that the addition of AOT surfactant promoted the microstructure of YIG in crystalline cubic-like structure. The magnetic properties were sensitive to the synthesis variables of annealing temperature, time and AOT surfactant concentration. The maximum saturation magnetization (28.13 emu/g), remanence magnetization (21.57 emu/g) and coercive force (703 Oe) were achieved at an annealing temperature of 1200 o C, time 2 h and 500 ppm of AOT surfactant concentration.

  20. Secure Data Aggregation in Wireless Sensor Network-Fujisaki Okamoto(FO) Authentication Scheme against Sybil Attack.

    Science.gov (United States)

    Nirmal Raja, K; Maraline Beno, M

    2017-07-01

    In the wireless sensor network(WSN) security is a major issue. There are several network security schemes proposed in research. In the network, malicious nodes obstruct the performance of the network. The network can be vulnerable by Sybil attack. When a node illicitly assertions multiple identities or claims fake IDs, the WSN grieves from an attack named Sybil attack. This attack threatens wireless sensor network in data aggregation, synchronizing system, routing, fair resource allocation and misbehavior detection. Henceforth, the research is carried out to prevent the Sybil attack and increase the performance of the network. This paper presents the novel security mechanism and Fujisaki Okamoto algorithm and also application of the work. The Fujisaki-Okamoto (FO) algorithm is ID based cryptographic scheme and gives strong authentication against Sybil attack. By using Network simulator2 (NS2) the scheme is simulated. In this proposed scheme broadcasting key, time taken for different key sizes, energy consumption, Packet delivery ratio, Throughput were analyzed.

  1. Inter-labeler and intra-labeler variability of condition severity classification models using active and passive learning methods.

    Science.gov (United States)

    Nissim, Nir; Shahar, Yuval; Elovici, Yuval; Hripcsak, George; Moskovitch, Robert

    2017-09-01

    Labeling instances by domain experts for classification is often time consuming and expensive. To reduce such labeling efforts, we had proposed the application of active learning (AL) methods, introduced our CAESAR-ALE framework for classifying the severity of clinical conditions, and shown its significant reduction of labeling efforts. The use of any of three AL methods (one well known [SVM-Margin], and two that we introduced [Exploitation and Combination_XA]) significantly reduced (by 48% to 64%) condition labeling efforts, compared to standard passive (random instance-selection) SVM learning. Furthermore, our new AL methods achieved maximal accuracy using 12% fewer labeled cases than the SVM-Margin AL method. However, because labelers have varying levels of expertise, a major issue associated with learning methods, and AL methods in particular, is how to best to use the labeling provided by a committee of labelers. First, we wanted to know, based on the labelers' learning curves, whether using AL methods (versus standard passive learning methods) has an effect on the Intra-labeler variability (within the learning curve of each labeler) and inter-labeler variability (among the learning curves of different labelers). Then, we wanted to examine the effect of learning (either passively or actively) from the labels created by the majority consensus of a group of labelers. We used our CAESAR-ALE framework for classifying the severity of clinical conditions, the three AL methods and the passive learning method, as mentioned above, to induce the classifications models. We used a dataset of 516 clinical conditions and their severity labeling, represented by features aggregated from the medical records of 1.9 million patients treated at Columbia University Medical Center. We analyzed the variance of the classification performance within (intra-labeler), and especially among (inter-labeler) the classification models that were induced by using the labels provided by seven

  2. Molecular typing of Legionella pneumophila from air-conditioning cooling waters using mip gene, SBT, and FAFLP methods.

    Science.gov (United States)

    Gong, Xiangli; Li, Juntao; Zhang, Ying; Hou, Shuiping; Qu, Pinghua; Yang, Zhicong; Chen, Shouyi

    2017-08-01

    Legionella spp. are important waterborne pathogens. Molecular typing has become an important method for outbreaks investigations and source tracking of Legionnaires. In a survey program conducted by the Guangzhou Center for Disease Control and Prevention, multiple serotypes Legionella pneumophila (L. pneumophila) were isolated from waters in air-conditioning cooling towers in urban Guangzhou region, China between 2008 and 2011. Three genotyping methods, mip (macrophage infectivity potentiator) genotyping, SBT (sequence-based typing), and FAFLP (fluorescent amplified fragment length polymorphism analysis) were used to type these waterborne L. pneumophila isolates. The three methods were capable of typing all the 134 isolates and a reference strain of L. pneumophila (ATCC33153), with discriminatory indices of 0.7034, 0.9218, and 0.9376, for the mip, SBT, and FAFLP methods respectively. Among the 9 serotypes of the 134 isolates, 10, 50, and 34 molecular types were detected by the mip, SBT, and FAFLP methods respectively. The mip genotyping and SBT typing are more feasible for inter-laboratory results sharing and comparison of different types of L. pneumophila. The SBT and FAFLP typing methods were rapid with higher discriminatory abilities. Combinations of two or more of the typing methods enables more accurate typing of Legionella isolates for outbreak investigations and source tracking of Legionnaires. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. An Engel condition with an additive mapping in semiprime rings

    Indian Academy of Sciences (India)

    ... Public Lectures · Lecture Workshops · Refresher Courses · Symposia · Live Streaming. Home; Journals; Proceedings – Mathematical Sciences; Volume 124; Issue 4. An Engel condition with an additive mapping in semiprime rings. Maja Fošner Nadeem Ur Rehman Joso Vukman. Volume 124 Issue 4 November 2014 pp ...

  4. A novel method of calibrating a MEMS inertial reference unit on a turntable under limited working conditions

    Science.gov (United States)

    Lu, Jiazhen; Liang, Shufang; Yang, Yanqiang

    2017-10-01

    Micro-electro-mechanical systems (MEMS) inertial measurement devices tend to be widely used in inertial navigation systems and have quickly emerged on the market due to their characteristics of low cost, high reliability and small size. Calibration is the most effective way to remove the deterministic error of an inertial reference unit (IRU), which in this paper consists of three orthogonally mounted MEMS gyros. However, common testing methods in the lab cannot predict the corresponding errors precisely when the turntable’s working condition is restricted. In this paper, the turntable can only provide a relatively small rotation angle. Moreover, the errors must be compensated exactly because of the great effect caused by the high angular velocity of the craft. To deal with this question, a new method is proposed to evaluate the MEMS IRU’s performance. In the calibration procedure, a one-axis table that can rotate a limited angle in the form of a sine function is utilized to provide the MEMS IRU’s angular velocity. A new algorithm based on Fourier series is designed to calculate the misalignment and scale factor errors. The proposed method is tested in a set of experiments, and the calibration results are compared to a traditional calibration method performed under normal working conditions to verify their correctness. In addition, a verification test in the given rotation speed is implemented for further demonstration.

  5. Basic study on optimal conditions for cranial MR angiography using signal targeting with alternating radiofrequency (STAR method)

    International Nuclear Information System (INIS)

    Kato, Joji; Kawamura, Yoshihiko; Saito, Haruyoshi; Ito, Kouichirou; Okada, Susumu; Moriya, Hirohito.

    1997-01-01

    In order to obtain the optimal conditions for cranial MRA by a rapid imaging method (fast card STAR), to which the principle of signal targeting with alternating radiofrequency (STAR method) was applied, we carried out a basic study on normal volunteers. According to the results, the vascular signal was weaker with FA 10 degrees, and ghost artifact was observed above 60 degrees. The FA at which good imaging of even peripheral vessels could be obtained was about 30 degrees. The visibility of the peripheral part increased with increased in-flow inversion time (TI), but at TI 500 ms, some weakening of the vascular signals was observed. Considering the imaging of peripheral vascularity and vascular contrast, TI 400 ms seemed to be most suitable. Regarding VPS (views per segment: collecting number of k-space lines during one cardiac pulse), slight blurring was observed at VPS 16, and this blurring caused a marked decrease in visibility at VPS 32. Although the VPS setting depends on imaging time, the imaging time for VPS 8 was short (about 30-60 sec) and artifact noise was slight. Thus, it was considered to be useful. This method reduced artifact noise under the optimal conditions for FA, TI and VPS and provided good images of blood vessels, showing that this method is useful. (author)

  6. Preliminay Investigation of Variation in Some Dark Adaptation Aspects fo Possible Relevance to Military Helicopter Aircrew.

    Science.gov (United States)

    1983-06-01

    not incorporate some of the critical specifications for measuring dark adaptation. 76Case reports of patients with coeliac disease defective 101diets...or end point of adaptation had been suspected. 2 The factors apart from disease and unusual conditions may be considered in two categories: those

  7. Modified Taylor series method for solving nonlinear differential equations with mixed boundary conditions defined on finite intervals.

    Science.gov (United States)

    Vazquez-Leal, Hector; Benhammouda, Brahim; Filobello-Nino, Uriel Antonio; Sarmiento-Reyes, Arturo; Jimenez-Fernandez, Victor Manuel; Marin-Hernandez, Antonio; Herrera-May, Agustin Leobardo; Diaz-Sanchez, Alejandro; Huerta-Chua, Jesus

    2014-01-01

    In this article, we propose the application of a modified Taylor series method (MTSM) for the approximation of nonlinear problems described on finite intervals. The issue of Taylor series method with mixed boundary conditions is circumvented using shooting constants and extra derivatives of the problem. In order to show the benefits of this proposal, three different kinds of problems are solved: three-point boundary valued problem (BVP) of third-order with a hyperbolic sine nonlinearity, two-point BVP for a second-order nonlinear differential equation with an exponential nonlinearity, and a two-point BVP for a third-order nonlinear differential equation with a radical nonlinearity. The result shows that the MTSM method is capable to generate easily computable and highly accurate approximations for nonlinear equations. 34L30.

  8. Effect of airfoil (trailing-edge) thickness on the numerical solution of panel methods based on the Dirichlet boundary condition

    Science.gov (United States)

    Yon, Steven; Katz, Joseph; Plotkin, Allen

    1992-01-01

    The practical limit of airfoil thickness ratio for which acceptable engineering results are obtainable with the Dirichlet boundary-condition-based numerical methods is investigated. This is done by studying the effect of thickness on the calculated pressure distribution near the trailing edge and by comparing the aerodynamic coefficients with available exact solutions. The first objective of this study, owing to the wide use of such computational methods, is to demonstrate the numerical symptoms that occur when the body or wing thickness approaches zero and to increase the awareness of potential users of these methods. Additionally, an effort is made to obtain the practical limits of the trailing-edge thickness where such problems will appear in the flow solution, and to propose some possible cures for very thin airfoils or those with cusped trailing edges.

  9. Modern Methods of Management Decision-Making in Entrepreneurial Structures Aimed at Sustainable Development in Conditions of Crisis

    Directory of Open Access Journals (Sweden)

    Marina Viktorovna Glazova

    2016-06-01

    Full Text Available The aim of the article is to develop a method for management decisionmaking, ensuring the sustainable development of enterprise structures in the conditions of crisis. To this end, the author makes a comparative analysis of modern methods of justification, adoption and implementation of administrative decisions in enterprise structures, focused on sustainable development in the conditions of crisis. The results of this analysis show that all of these methods involve quantifying the scale of different criteria, which do not reflect causal logic of the preferences of some other criteria. The results of the ranking cannot be distinguished from a number of other similar ratings (with slight differences in the weights, therefore, the expected nature of the uniqueness of the decision-making model is not provided. To solve the problems indicated in this paper, we propose an alternative approach to the aggregation of conflicting preferences of managerial decisions: to come up with a quality solution to resolve conflicts between the preferences of solutions through a variety of criteria, and to aggregate them to the final decision. The author develops unified method of decision-making. The fact that the method provides information to clarify the criteria values and the reasons for their relative importance to the decision makes it particularly attractive in times of crisis, as it creates an opportunity for the delegation of authority and the use of standard solutions. It allows to reflect the logic and the causal relationships of ranking criteria, as well as to simplify the process of management decision-making, eliminating it from a difficult procedure for placing the weighting factors. The method is recommended for the use in making decisions with a small number of options and criteria. It can also be used as a test has taken management decisions, taking into account only the most significant criteria.

  10. Study on the optimal moisture adding rate of brown rice during germination by using segmented moisture conditioning method.

    Science.gov (United States)

    Cao, Yinping; Jia, Fuguo; Han, Yanlong; Liu, Yang; Zhang, Qiang

    2015-10-01

    The aim of this study was to find out the optimal moisture adding rate of brown rice during the process of germination. The process of water addition in brown rice could be divided into three stages according to different water absorption speeds in soaking process. Water was added with three different speeds in three stages to get the optimal water adding rate in the whole process of germination. Thus, the technology of segmented moisture conditioning which is a method of adding water gradually was put forward. Germinated brown rice was produced by using segmented moisture conditioning method to reduce the loss of water-soluble nutrients and was beneficial to the accumulation of gamma aminobutyric acid. The effects of once moisture adding amount in three stages on the gamma aminobutyric acid content in germinated brown rice and germination rate of brown rice were investigated by using response surface methodology. The optimum process parameters were obtained as follows: once moisture adding amount of stage I with 1.06 %/h, once moisture adding amount of stage II with 1.42 %/h and once moisture adding amount of stage III with 1.31 %/h. The germination rate under the optimum parameters was 91.33 %, which was 7.45 % higher than that of germinated brown rice produced by soaking method (84.97 %). The content of gamma aminobutyric acid in germinated brown rice under the optimum parameters was 29.03 mg/100 g, which was more than two times higher than that of germinated brown rice produced by soaking method (12.81 mg/100 g). The technology of segmented moisture conditioning has potential applications for studying many other cereals.

  11. A Hybrid Finite Element-Fourier Spectral Method for Vibration Analysis of Structures with Elastic Boundary Conditions

    Directory of Open Access Journals (Sweden)

    Wan-You Li

    2014-01-01

    Full Text Available A novel hybrid method, which simultaneously possesses the efficiency of Fourier spectral method (FSM and the applicability of the finite element method (FEM, is presented for the vibration analysis of structures with elastic boundary conditions. The FSM, as one type of analytical approaches with excellent convergence and accuracy, is mainly limited to problems with relatively regular geometry. The purpose of the current study is to extend the FSM to problems with irregular geometry via the FEM and attempt to take full advantage of the FSM and the conventional FEM for structural vibration problems. The computational domain of general shape is divided into several subdomains firstly, some of which are represented by the FSM while the rest by the FEM. Then, fictitious springs are introduced for connecting these subdomains. Sufficient details are given to describe the development of such a hybrid method. Numerical examples of a one-dimensional Euler-Bernoulli beam and a two-dimensional rectangular plate show that the present method has good accuracy and efficiency. Further, one irregular-shaped plate which consists of one rectangular plate and one semi-circular plate also demonstrates the capability of the present method applied to irregular structures.

  12. Effect of the Pilates method on physical conditioning of healthy subjects: a systematic review and meta-analysis.

    Science.gov (United States)

    Campos, Renata R; Dias, Josilainne M; Pereira, Ligia M; Obara, Karen; Barreto, Maria S; Silva, Mariana F; Mazuquin, Bruno F; Christofaro, Diego G; Fernandes, Romulo A; Iversen, Maura D; Cardoso, Jefferson R

    2016-01-01

    Physical conditioning consists of a variety of health-related attributes and Pilates exercises are described as a form of this conditioning. The objective of this systematic review was to determine the effect of the Pilates method on health and ability outcome of the physical conditioning of healthy individuals. The search was performed in the following databases: Medline, Cinahl, Embase, Lilacs, Scielo, Web of Science, PEDro, Cochrane Controlled Trials Register Library, Scopus, Science Direct and Google Scholar. (1950-2014). Included studies were randomized controlled trials (RCTs) that assessed the effects of the Pilates method on healthy subjects. Nine RCTs met the inclusion criteria. Pilates improved abdominal muscular endurance when compared with no exercises (mean difference [MD]=9.53%; 95% CI: 2.41, 16.43; P=0.009), however, there was no difference in flexibility (MD=4.97; 95% CI: -0.53, 10.47; P=0.08). Some positive effects (up to 6 months) of the Pilates practice were found in some RCTs' results as follows: Improvement of dynamic balance, quality of life and back muscle flexibility. The results indicate the Pilates exercises performed on the mat or apparatus 2 to 3 times a week, for 5 to 12 weeks, improves abdominal muscular endurance (on average, 10 more abdominals curls in 1-minute sit-up test) for both genders, when compared to no exercises.

  13. A novel CFS-PML boundary condition for transient electromagnetic simulation using a fictitious wave domain method

    Science.gov (United States)

    Hu, Yanpu; Egbert, Gary; Ji, Yanju; Fang, Guangyou

    2017-01-01

    In this study, we apply fictitious wave domain (FWD) methods, based on the correspondence principle for the wave and diffusion fields, to finite difference (FD) modeling of transient electromagnetic (TEM) diffusion problems for geophysical applications. A novel complex frequency shifted perfectly matched layer (PML) boundary condition is adapted to the FWD to truncate the computational domain, with the maximum electromagnetic wave propagation velocity in the FWD used to set the absorbing parameters for the boundary layers. Using domains of varying spatial extent we demonstrate that these boundary conditions offer significant improvements over simpler PML approaches, which can result in spurious reflections and large errors in the FWD solutions, especially for low frequencies and late times. In our development, resistive air layers are directly included in the FWD, allowing simulation of TEM responses in the presence of topography, as is commonly encountered in geophysical applications. We compare responses obtained by our new FD-FWD approach and with the spectral Lanczos decomposition method on 3-D resistivity models of varying complexity. The comparisons demonstrate that our absorbing boundary condition in FWD for the TEM diffusion problems works well even in complex high-contrast conductivity models.

  14. Validation of newly developed and redesigned key indicator methods for assessment of different working conditions with physical workloads based on mixed-methods design: a study protocol

    Science.gov (United States)

    Liebers, Falk; Brandstädt, Felix; Schust, Marianne; Serafin, Patrick; Schäfer, Andreas; Gebhardt, Hansjürgen; Hartmann, Bernd; Steinberg, Ulf

    2017-01-01

    Introduction The impact of work-related musculoskeletal disorders is considerable. The assessment of work tasks with physical workloads is crucial to estimate the work-related health risks of exposed employees. Three key indicator methods are available for risk assessment regarding manual lifting, holding and carrying of loads; manual pulling and pushing of loads; and manual handling operations. Three further KIMs for risk assessment regarding whole-body forces, awkward body postures and body movement have been developed de novo. In addition, the development of a newly drafted combined method for mixed exposures is planned. All methods will be validated regarding face validity, reliability, convergent validity, criterion validity and further aspects of utility under practical conditions. Methods and analysis As part of the joint project MEGAPHYS (multilevel risk assessment of physical workloads), a mixed-methods study is being designed for the validation of KIMs and conducted in companies of different sizes and branches in Germany. Workplaces are documented and analysed by observations, applying KIMs, interviews and assessment of environmental conditions. Furthermore, a survey among the employees at the respective workplaces takes place with standardised questionnaires, interviews and physical examinations. It is intended to include 1200 employees at 120 different workplaces. For analysis of the quality criteria, recommendations of the COSMIN checklist (COnsensus-based Standards for the selection of health Measurement INstruments) will be taken into account. Ethics and dissemination The study was planned and conducted in accordance with the German Medical Professional Code and the Declaration of Helsinki as well as the German Federal Data Protection Act. The design of the study was approved by ethics committees. We intend to publish the validated KIMs in 2018. Results will be published in peer-reviewed journals, presented at international meetings and disseminated

  15. Effects of Remote Ischemic Conditioning Methods on Ischemia-Reperfusion Injury in Muscle Flaps: An Experimental Study in Rats

    Directory of Open Access Journals (Sweden)

    Durdane Keskin

    2017-09-01

    Full Text Available Background The aim of this study was to investigate the effects of remote ischemic conditioning on ischemia-reperfusion injury in rat muscle flaps histopathologically and biochemically. Methods Thirty albino rats were divided into 5 groups. No procedure was performed in the rats in group 1, and only blood samples were taken. A gracilis muscle flap was elevated in all the other groups. Microclamps were applied to the vascular pedicle for 4 hours in order to achieve tissue ischemia. In group 2, no additional procedure was performed. In groups 3, 4, and 5, the right hind limb was used and 3 cycles of ischemia-reperfusion for 5 minutes each (total, 30 minutes was applied with a latex tourniquet (remote ischemic conditioning. In group 3, this procedure was performed before flap elevation (remote ischemic preconditoning. In group 4, the procedure was performed 4 hours after flap ischemia (remote ischemic postconditioning. In group 5, the procedure was performed after the flap was elevated, during the muscle flap ischemia episode (remote ischemic perconditioning. Results The histopathological damage score in all remote conditioning ischemia groups was lower than in the ischemic-reperfusion group. The lowest histopathological damage score was observed in group 5 (remote ischemic perconditioning. Conclusions The nitric oxide levels were higher in the blood samples obtained from the remote ischemic perconditioning group. This study showed the effectiveness of remote ischemic conditioning procedures and compared their usefulness for preventing ischemia-reperfusion injury in muscle flaps.

  16. Diagnosis of Insulation Condition of MV Switchgears by Application of Different Partial Discharge Measuring Methods and Sensors

    Directory of Open Access Journals (Sweden)

    Fernando Álvarez Gómez

    2018-02-01

    Full Text Available Partial discharges (PD measurement provides valuable information for the condition assessment of the insulation status of high-voltage (HV electrical installations. During the last three decades, several PD sensors and measuring techniques have been developed to perform accurate diagnostics when PD measurements are carried out on-site and on-line. For utilities, the most attractive characteristics of on-line measurements are that once the sensors are installed in the grid, the electrical service is uninterrupted and that electrical systems are tested in real operating conditions. In medium-voltage (MV and HV installations, one of the critical points where an insulation defect can occur is inside metal-clad switchgears (including the cable terminals connected to them. Thus, this kind of equipment is increasingly being monitored to carry out proper maintenance based on their condition. This paper presents a study concerning the application of different electromagnetic measuring techniques (compliant with IEC 62478 and IEC 60270 standards, together with the use of suitable sensors, which enable the evaluation of the insulation condition mainly in MV switchgears. The main scope is to give a general overview about appropriate types of electromagnetic measuring methods and sensors to be applied, while considering the level of detail and accuracy in the diagnosis and the particular fail-save requirements of the electrical installations where the switchgears are located.

  17. Diagnosis of Insulation Condition of MV Switchgears by Application of Different Partial Discharge Measuring Methods and Sensors.

    Science.gov (United States)

    Álvarez Gómez, Fernando; Albarracín-Sánchez, Ricardo; Garnacho Vecino, Fernando; Granizo Arrabé, Ricardo

    2018-02-28

    Partial discharges (PD) measurement provides valuable information for the condition assessment of the insulation status of high-voltage (HV) electrical installations. During the last three decades, several PD sensors and measuring techniques have been developed to perform accurate diagnostics when PD measurements are carried out on-site and on-line. For utilities, the most attractive characteristics of on-line measurements are that once the sensors are installed in the grid, the electrical service is uninterrupted and that electrical systems are tested in real operating conditions. In medium-voltage (MV) and HV installations, one of the critical points where an insulation defect can occur is inside metal-clad switchgears (including the cable terminals connected to them). Thus, this kind of equipment is increasingly being monitored to carry out proper maintenance based on their condition. This paper presents a study concerning the application of different electromagnetic measuring techniques (compliant with IEC 62478 and IEC 60270 standards), together with the use of suitable sensors, which enable the evaluation of the insulation condition mainly in MV switchgears. The main scope is to give a general overview about appropriate types of electromagnetic measuring methods and sensors to be applied, while considering the level of detail and accuracy in the diagnosis and the particular fail-save requirements of the electrical installations where the switchgears are located.

  18. THE THEORETICAL AND METHODICAL APPROACH TO AN ASSESSMENT OF A LEVEL OF DEVELOPMENT OF THE ENTERPRISE IN CONDITIONS OF GLOBALIZATION

    Directory of Open Access Journals (Sweden)

    Tatiana Shved

    2016-11-01

    Full Text Available The subject of this article is theoretical, methodical and practical aspects of enterprise development in conditions of globalization. The purpose of this research is to provide theoretical and methodical approach to an assessment of a level of development of the enterprise, which is based on the relationship between the factors and influence, illustrating the effect of the internal and external environment of enterprises functioning, and indicates the level of development of the enterprise. Methodology. Theoretical basis of the study was the examination and rethinking of the main achievements of world and domestic science on the development of enterprises. To achieve the objectives of the research following methods were used: systemic and structural analysis for the formation of methodical approaches to the selection of the factors, influencing the development of enterprises; abstract and logical – for the formulation of conclusions and proposals; the method of valuation and expert assessments to the implementation of the proposed theoretical and methodical approach to an assessment of a level of development of the enterprise in conditions of globalization. Results of the research is the proposed theoretical and methodical to an assessment of a level of development of the enterprise in conditions of globalization, which is associated with the idea of development of the enterprise as a system with inputs–factors, influencing on the development , and outputs – indicators of the level of enterprise development within these factors. So, the chosen factors – resources, financial-economic activity, innovation and investment activities, competition, government influence, and foreign trade. Indicators that express these factors, are capital productivity, labour productivity, material efficiency within the first factor; the profitability of the activity, the coefficient of current assets, the total liquidity coefficient, financial stability

  19. Comparison of the methods for discrete approximation of the fractional-order operator

    Directory of Open Access Journals (Sweden)

    Zborovjan Martin

    2003-12-01

    Full Text Available In this paper we will present some alternative types of discretization methods (discrete approximation for the fractional-order (FO differentiator and their application to the FO dynamical system described by the FO differential equation (FDE. With analytical solution and numerical solution by power series expansion (PSE method are compared two effective methods - the Muir expansion of the Tustin operator and continued fraction expansion method (CFE with the Tustin operator and the Al-Alaoui operator. Except detailed mathematical description presented are also simulation results. From the Bode plots of the FO differentiator and FDE and from the solution in the time domain we can see, that the CFE is a more effective method according to the PSE method, but there are some restrictions for the choice of the time step. The Muir expansion is almost unusable.

  20. Negative Subtraction Hybridization: An efficient method to isolate large numbers of condition-specific cDNAs

    Directory of Open Access Journals (Sweden)

    Hall Leo T

    2004-03-01

    Full Text Available Abstract Background The construction of cDNA libraries is a useful tool to understand gene expression in organisms under different conditions, but random sequencing of unbiased cDNA collections is laborious and can give rise to redundant EST collections. We aimed to isolate cDNAs of messages induced by switching Aspergillus nidulans from growth on glucose to growth on selected polysaccharides. Approximately 4,700 contigs from 12,320 ESTs were already available from a cDNA library representing transcripts isolated from glucose-grown A. nidulans during asexual development. Our goals were to expand the cDNA collection without repeated sequencing of previously identified ESTs and to find as many transcripts as possible that are specifically induced in complex polysaccharide metabolism. Results We have devised a Negative Subtraction Hybridization (NSH method and tested it in A. nidulans. NSH entails screening a plasmid library made from cDNAs prepared from cells grown under a selected physiological condition with labeled cDNA probes prepared from another physiological condition. Plasmids with inserts that failed to hybridize to cDNA probes through two rounds of screening (i.e. negatives indicate that they are transcripts present at low concentration in the labeled probe pool. Thus, these transcripts will be predominantly condition-specific, along with some rare transcripts. In a screen for transcripts induced by switching the carbon source from glucose to 12 selected polysaccharides, 3,532 negatives were isolated from approximately 100,000 surveyed colonies using this method. Negative clones were end-sequenced and assembled into 2,039 contigs, of which 1,722 were not present in the previously characterized glucose-grown cDNA library. Single-channel microarray hybridization experiments confirmed that the majority of the negatives represented genes that were differentially induced by a switch from growth in glucose to one or more of the polysaccharides

  1. Discrimination Method of Pop-up Conditions according to PC Usage Situation for Dissemination of Business Information

    Science.gov (United States)

    Matsumoto, Toshiko; Onoyama, Takashi; Akiyoshi, Masanori

    Recently, digital documents in companies increase rapidly and are required to be ensured. Pop-up of business information according to PC usage situation can achieve this goal. Two functions are required to it: One is to correctly discriminate pop-up conditions from contents of business-use application, and the other is to select suppression keywords from incorrect pop-up documents. The suppression keywords should improve true negative rate without drop of recall. Based on observation of typical phrases and increase of frequencies for characteristic phrases in contents of business-use applications, we select suppression keywords according to their frequency in positive and negative cases and their occurrence in feedback document. Our evaluation using three kinds of business information shows that the proposed method can achieve both high true negative rate and high recall, and to correctly discriminate pop-up conditions.

  2. A GPU-accelerated nodal discontinuous Galerkin method with high-order absorbing boundary conditions and corner/edge compatibility

    Science.gov (United States)

    Modave, A.; Atle, A.; Chan, J.; Warburton, T.

    2017-12-01

    Discontinuous Galerkin finite element schemes exhibit attractive features for accurate large-scale wave-propagation simulations on modern parallel architectures. For many applications, these schemes must be coupled with non-reflective boundary treatments to limit the size of the computational domain without losing accuracy or computational efficiency, which remains a challenging task. In this paper, we present a combination of a nodal discontinuous Galerkin method with high-order absorbing boundary conditions (HABCs) for cuboidal computational domains. Compatibility conditions are derived for HABCs intersecting at the edges and the corners of a cuboidal domain. We propose a GPU implementation of the computational procedure, which results in a multidimensional solver with equations to be solved on 0D, 1D, 2D and 3D spatial regions. Numerical results demonstrate both the accuracy and the computational efficiency of our approach.

  3. Re-evaluation of the sorption behaviour of Bromide and Sulfamethazine under field conditions using leaching data and modelling methods

    Science.gov (United States)

    Gassmann, Matthias; Olsson, Oliver; Höper, Heinrich; Hamscher, Gerd; Kümmerer, Klaus

    2016-04-01

    The simulation of reactive transport in the aquatic environment is hampered by the ambiguity of environmental fate process conceptualizations for a specific substance in the literature. Concepts are usually identified by experimental studies and inverse modelling under controlled lab conditions in order to reduce environmental uncertainties such as uncertain boundary conditions and input data. However, since environmental conditions affect substance behaviour, a re-evaluation might be necessary under environmental conditions which might, in turn, be affected by uncertainties. Using a combination of experimental data and simulations of the leaching behaviour of the veterinary antibiotic Sulfamethazine (SMZ; synonym: sulfadimidine) and the hydrological tracer Bromide (Br) in a field lysimeter, we re-evaluated the sorption concepts of both substances under uncertain field conditions. Sampling data of a field lysimeter experiment in which both substances were applied twice a year with manure and sampled at the bottom of two lysimeters during three subsequent years was used for model set-up and evaluation. The total amount of leached SMZ and Br were 22 μg and 129 mg, respectively. A reactive transport model was parameterized to the conditions of the two lysimeters filled with monoliths (depth 2 m, area 1 m²) of a sandy soil showing a low pH value under which Bromide is sorptive. We used different sorption concepts such as constant and organic-carbon dependent sorption coefficients and instantaneous and kinetic sorption equilibrium. Combining the sorption concepts resulted in four scenarios per substance with different equations for sorption equilibrium and sorption kinetics. The GLUE (Generalized Likelihood Uncertainty Estimation) method was applied to each scenario using parameter ranges found in experimental and modelling studies. The parameter spaces for each scenario were sampled using a Latin Hypercube method which was refined around local model efficiency maxima

  4. Numeric simulation model for long-term orthodontic tooth movement with contact boundary conditions using the finite element method.

    Science.gov (United States)

    Hamanaka, Ryo; Yamaoka, Satoshi; Anh, Tuan Nguyen; Tominaga, Jun-Ya; Koga, Yoshiyuki; Yoshida, Noriaki

    2017-11-01

    Although many attempts have been made to simulate orthodontic tooth movement using the finite element method, most were limited to analyses of the initial displacement in the periodontal ligament and were insufficient to evaluate the effect of orthodontic appliances on long-term tooth movement. Numeric simulation of long-term tooth movement was performed in some studies; however, neither the play between the brackets and archwire nor the interproximal contact forces were considered. The objectives of this study were to simulate long-term orthodontic tooth movement with the edgewise appliance by incorporating those contact conditions into the finite element model and to determine the force system when the space is closed with sliding mechanics. We constructed a 3-dimensional model of maxillary dentition with 0.022-in brackets and 0.019 × 0.025-in archwire. Forces of 100 cN simulating sliding mechanics were applied. The simulation was accomplished on the assumption that bone remodeling correlates with the initial tooth displacement. This method could successfully represent the changes in the moment-to-force ratio: the tooth movement pattern during space closure. We developed a novel method that could simulate the long-term orthodontic tooth movement and accurately determine the force system in the course of time by incorporating contact boundary conditions into finite element analysis. It was also suggested that friction is progressively increased during space closure in sliding mechanics. Copyright © 2017. Published by Elsevier Inc.

  5. A method for automatic segmentation and splitting of hyperspectral images of raspberry plants collected in field conditions

    Directory of Open Access Journals (Sweden)

    Dominic Williams

    2017-11-01

    Full Text Available Abstract Hyperspectral imaging is a technology that can be used to monitor plant responses to stress. Hyperspectral images have a full spectrum for each pixel in the image, 400–2500 nm in this case, giving detailed information about the spectral reflectance of the plant. Although this technology has been used in laboratory-based controlled lighting conditions for early detection of plant disease, the transfer of such technology to imaging plants in field conditions presents a number of challenges. These include problems caused by varying light levels and difficulties of separating the target plant from its background. Here we present an automated method that has been developed to segment raspberry plants from the background using a selected spectral ratio combined with edge detection. Graph theory was used to minimise a cost function to detect the continuous boundary between uninteresting plants and the area of interest. The method includes automatic detection of a known reflectance tile which was kept constantly within the field of view for all image scans. A method to split images containing rows of multiple raspberry plants into individual plants was also developed. Validation was carried out by comparison of plant height and density measurements with manually scored values. A reasonable correlation was found between these manual scores and measurements taken from the images (r2 = 0.75 for plant height. These preliminary steps are an essential requirement before detailed spectral analysis of the plants can be achieved.

  6. Estimates of metabolic rate and major constituents of metabolic demand in fishes under field conditions: Methods, proxies, and new perspectives.

    Science.gov (United States)

    Treberg, Jason R; Killen, Shaun S; MacCormack, Tyson J; Lamarre, Simon G; Enders, Eva C

    2016-12-01

    Metabolic costs are central to individual energy budgets, making estimates of metabolic rate vital to understanding how an organism interacts with its environment as well as the role of species in their ecosystem. Despite the ecological and commercial importance of fishes, there are currently no widely adopted means of measuring field metabolic rate in fishes. The lack of recognized methods is in part due to the logistical difficulties of measuring metabolic rates in free swimming fishes. However, further development and refinement of techniques applicable for field-based studies on free swimming animals would greatly enhance the capacity to study fish under environmentally relevant conditions. In an effort to foster discussion in this area, from field ecologists to biochemists alike, we review aspects of energy metabolism and give details on approaches that have been used to estimate energetic parameters in fishes. In some cases, the techniques have been applied to field conditions; while in others, the methods have been primarily used on laboratory held fishes but should be applicable, with validation, to fishes in their natural environment. Limitations, experimental considerations and caveats of these measurements and the study of metabolism in wild fishes in general are also discussed. Potential novel approaches to FMR estimates are also presented for consideration. The innovation of methods for measuring field metabolic rate in free-ranging wild fish would revolutionize the study of physiological ecology. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Computation of identity by descent probabilities conditional on DNA markers via a Monte Carlo Markov Chain method

    Directory of Open Access Journals (Sweden)

    Pérez-Enciso Miguel

    2000-09-01

    Full Text Available Abstract The accurate estimation of the probability of identity by descent (IBD at loci or genome positions of interest is paramount to the genetic study of quantitative and disease resistance traits. We present a Monte Carlo Markov Chain method to compute IBD probabilities between individuals conditional on DNA markers and on pedigree information. The IBDs can be obtained in a completely general pedigree at any genome position of interest, and all marker and pedigree information available is used. The method can be split into two steps at each iteration. First, phases are sampled using current genotypic configurations of relatives and second, crossover events are simulated conditional on phases. Internal track is kept of all founder origins and crossovers such that the IBD probabilities averaged over replicates are rapidly obtained. We illustrate the method with some examples. First, we show that all pedigree information should be used to obtain line origin probabilities in F2 crosses. Second, the distribution of genetic relationships between half and full sibs is analysed in both simulated data and in real data from an F2 cross in pigs.

  8. The methodic of an estimate of the technical condition of tank wagons of a park of industrial enterprises

    Directory of Open Access Journals (Sweden)

    Валерія Сергіївна Воропай

    2015-03-01

    Full Text Available The article proposed a method to evaluate the technical condition of tank wagons that are operated chemical industry. An algorithm for performing work on the evaluation of the technical condition of tank wagons was developed, which allows on the basis of diagnosis and analysis of current condition to justify a further period of operation. The complex of works on testing of the tanks and mathematical models for the implementation of calculations on the strength and reliability of the design were proposed. The article is devoted to solving the problem of the effective exploitation of the working fleet of tank wagons industries by detecting the presence of residual life and life extension. Opportunities for further exploitation of cars the complex of works on the assessment of technical conditions and the calculation of the stock of the resource in article are proposed. Operational research of the park chemical industries has reduced the shortage of rolling stock for transportation of ammonia. The analysis of the many faults of the chassis and the main elements of the support structure of tank wagons after 20 years of operation was made. The algorithm of determining the residual life of the specialized tank wagons operated in an industrial plant is proposed. Scientific novelty defined algorithm and the results obtained is the main justification of operational parameters for tank wagons carrying liquid ammonia, in accordance with the test load. The methodic for resource conservation of tank wagons carrying cargo under high pressure was proposed at first. In this article performance improved procedure for identifying residual life, this has both theoretical and practical importance

  9. Seed storage at elevated partial pressure of oxygen, a fast method for analysing seed ageing under dry conditions.

    Science.gov (United States)

    Groot, S P C; Surki, A A; de Vos, R C H; Kodde, J

    2012-11-01

    Despite differences in physiology between dry and relative moist seeds, seed ageing tests most often use a temperature and seed moisture level that are higher than during dry storage used in commercial practice and gene banks. This study aimed to test whether seed ageing under dry conditions can be accelerated by storing under high-pressure oxygen. methods: Dry barley (Hordeum vulgare), cabbage (Brassica oleracea), lettuce (Lactuca sativa) and soybean (Glycine max) seeds were stored between 2 and 7 weeks in steel tanks under 18 MPa partial pressure of oxygen. Storage under high-pressure nitrogen gas or under ambient air pressure served as controls. The method was compared with storage at 45 °C after equilibration at 85 % relative humidity and long-term storage at the laboratory bench. Germination behaviour, seedling morphology and tocopherol levels were assessed. The ageing of the dry seeds was indeed accelerated by storing under high-pressure oxygen. The morphological ageing symptoms of the stored seeds resembled those observed after ageing under long-term dry storage conditions. Barley appeared more tolerant of this storage treatment compared with lettuce and soybean. Less-mature harvested cabbage seeds were more sensitive, as was the case for primed compared with non-primed lettuce seeds. Under high-pressure oxygen storage the tocopherol levels of dry seeds decreased, in a linear way with the decline in seed germination, but remained unchanged in seeds deteriorated during storage at 45 °C after equilibration at 85 % RH. Seed storage under high-pressure oxygen offers a novel and relatively fast method to study the physiology and biochemistry of seed ageing at different seed moisture levels and temperatures, including those that are representative of the dry storage conditions as used in gene banks and commercial practice.

  10. Seed storage at elevated partial pressure of oxygen, a fast method for analysing seed ageing under dry conditions

    Science.gov (United States)

    Groot, S. P. C.; Surki, A. A.; de Vos, R. C. H.; Kodde, J.

    2012-01-01

    Background and Aims Despite differences in physiology between dry and relative moist seeds, seed ageing tests most often use a temperature and seed moisture level that are higher than during dry storage used in commercial practice and gene banks. This study aimed to test whether seed ageing under dry conditions can be accelerated by storing under high-pressure oxygen. Methods Dry barley (Hordeum vulgare), cabbage (Brassica oleracea), lettuce (Lactuca sativa) and soybean (Glycine max) seeds were stored between 2 and 7 weeks in steel tanks under 18 MPa partial pressure of oxygen. Storage under high-pressure nitrogen gas or under ambient air pressure served as controls. The method was compared with storage at 45 °C after equilibration at 85 % relative humidity and long-term storage at the laboratory bench. Germination behaviour, seedling morphology and tocopherol levels were assessed. Key Results The ageing of the dry seeds was indeed accelerated by storing under high-pressure oxygen. The morphological ageing symptoms of the stored seeds resembled those observed after ageing under long-term dry storage conditions. Barley appeared more tolerant of this storage treatment compared with lettuce and soybean. Less-mature harvested cabbage seeds were more sensitive, as was the case for primed compared with non-primed lettuce seeds. Under high-pressure oxygen storage the tocopherol levels of dry seeds decreased, in a linear way with the decline in seed germination, but remained unchanged in seeds deteriorated during storage at 45 °C after equilibration at 85 % RH. Conclusions Seed storage under high-pressure oxygen offers a novel and relatively fast method to study the physiology and biochemistry of seed ageing at different seed moisture levels and temperatures, including those that are representative of the dry storage conditions as used in gene banks and commercial practice. PMID:22967856

  11. Determination of clothing evaporative resistance on a sweating thermal manikin in an isothermal condition: heat loss method or mass loss method?

    Science.gov (United States)

    Wang, Faming; Gao, Chuansi; Kuklane, Kalev; Holmér, Ingvar

    2011-08-01

    This paper addresses selection between two calculation options, i.e heat loss option and mass loss option, for thermal manikin measurements on clothing evaporative resistance conducted in an isothermal condition (T(manikin) = T(a) = T(r)). Five vocational clothing ensembles with a thermal insulation range of 1.05-2.58 clo were selected and measured on a sweating thermal manikin 'Tore'. The reasons why the isothermal heat loss method generates a higher evaporative resistance than that of the mass loss method were thoroughly investigated. In addition, an indirect approach was applied to determine the amount of evaporative heat energy taken from the environment. It was found that clothing evaporative resistance values by the heat loss option were 11.2-37.1% greater than those based on the mass loss option. The percentage of evaporative heat loss taken from the environment (H(e,env)) for all test scenarios ranged from 10.9 to 23.8%. The real evaporative cooling efficiency ranged from 0.762 to 0.891, respectively. Furthermore, it is evident that the evaporative heat loss difference introduced by those two options was equal to the heat energy taken from the environment. In order to eliminate the combined effects of dry heat transfer, condensation, and heat pipe on clothing evaporative resistance, it is suggested that manikin measurements on the determination of clothing evaporative resistance should be performed in an isothermal condition. Moreover, the mass loss method should be applied to calculate clothing evaporative resistance. The isothermal heat loss method would appear to overestimate heat stress and thus should be corrected before use.

  12. Validation of newly developed and redesigned key indicator methods for assessment of different working conditions with physical workloads based on mixed-methods design: a study protocol.

    Science.gov (United States)

    Klussmann, Andre; Liebers, Falk; Brandstädt, Felix; Schust, Marianne; Serafin, Patrick; Schäfer, Andreas; Gebhardt, Hansjürgen; Hartmann, Bernd; Steinberg, Ulf

    2017-08-21

    The impact of work-related musculoskeletal disorders is considerable. The assessment of work tasks with physical workloads is crucial to estimate the work-related health risks of exposed employees. Three key indicator methods are available for risk assessment regarding manual lifting, holding and carrying of loads; manual pulling and pushing of loads; and manual handling operations. Three further KIMs for risk assessment regarding whole-body forces, awkward body postures and body movement have been developed de novo. In addition, the development of a newly drafted combined method for mixed exposures is planned. All methods will be validated regarding face validity, reliability, convergent validity, criterion validity and further aspects of utility under practical conditions. As part of the joint project MEGAPHYS (multilevel risk assessment of physical workloads), a mixed-methods study is being designed for the validation of KIMs and conducted in companies of different sizes and branches in Germany. Workplaces are documented and analysed by observations, applying KIMs, interviews and assessment of environmental conditions. Furthermore, a survey among the employees at the respective workplaces takes place with standardised questionnaires, interviews and physical examinations. It is intended to include 1200 employees at 120 different workplaces. For analysis of the quality criteria, recommendations of the COSMIN checklist (COnsensus-based Standards for the selection of health Measurement INstruments) will be taken into account. The study was planned and conducted in accordance with the German Medical Professional Code and the Declaration of Helsinki as well as the German Federal Data Protection Act. The design of the study was approved by ethics committees. We intend to publish the validated KIMs in 2018. Results will be published in peer-reviewed journals, presented at international meetings and disseminated to actual users for practical application. © Article

  13. A molecular marker of disease activity in autoimmune liver diseases with histopathological correlation; FoXp3/RORγt ratio.

    Science.gov (United States)

    Mitra, Suvradeep; Anand, Shashi; Das, Ashim; Thapa, Baburam; Chawla, Yogesh Kumar; Minz, Ranjana Walker

    2015-11-01

    Autoimmune liver diseases (AILDs) encompass a group of diseases with variable clinicopathological manifestations. Th17 and Treg cells have roles in the pathogenesis of AILDs with a balance shifted towards a relative increase in activity of the Th17 cells. In this study, the balance between the transcription factors of Treg and Th17 cells (FoXp3 and RORγt) was sought as a molecular marker of disease activity and to highlight the pathogenesis. The peripheral blood samples of 46 treatment-naive patients were collected and RNA was extracted. Real time PCR was performed and the ratio of gene expression was calculated. Histopathology of 18 patients was obtained and the activity score of these biopsies were also corroborated with their respective molecular (FoXp3/RORγt) (FRGT=FoXp3-ROR Gamma T) ratio. The FRGT ratio in healthy individuals was close to 1 and in disease the ratio changed significantly. This ratio (FRGT) was not significantly different in different varieties of AILD or in adult or paediatric form of the disease. However, the ratio remained consistently below 1 (mean 0.3) in acute disease and high (mean 224.7) in chronic or asymptomatic form of the disease (p disease as compared to Treg (FoXp3) and the reverse in chronic form. This ratio can be an important peripheral molecular marker to assess the disease activity without the necessity of performing a liver biopsy. © 2015 APMIS. Published by John Wiley & Sons Ltd.

  14. Advanced oxidation of biorefractory organics in aqueous solution together with bioelectricity generation by microbial fuel cells with composite FO/GPEs

    Science.gov (United States)

    Fu, Bao-rong; Shen, Chao; Ren, Jing; Chen, Jia-yi; Zhao, Lin

    2018-03-01

    In this study, ferric oxide loading graphite particle electrodes (FO/GPEs) were prepared as cathode of a three-dimensional electrode MFC-Fenton system. The properties of the composite cathode were examined with higher surface area and more mesopores. FO/GPEs could work as both cathode and Fenton iron reagents, contributing to high oxidation activity and better performance of electricity generation. The application of FO/GPEs MFC-Fenton system on degrading p-nitrophenol presented high catalytic efficiency in a wide range of pH value. The removal of p-nitrophenol and TOC attained to about 85 % within 8 and 64 h at neutral pH, respectively. A neutral FO/GPEs MFC-Fenton oxidation mechanism was also proposed. Specifically, both the surface iron sites and dissolved iron ions catalyzed the decomposition of H2O2. As results, the generated hydroxyl radicals were used for p-nitrophenol degradation and the iron oxide was recycled.

  15. Monitoring transient elastic energy storage within the rotary motors of single FoF1-ATP synthase by DCO-ALEX FRET

    Science.gov (United States)

    Ernst, Stefan; Düser, Monika G.; Zarrabi, Nawid; Börsch, Michael

    2012-03-01

    The enzyme FoF1-ATP synthase provides the 'chemical energy currency' adenosine triphosphate (ATP) for living cells. Catalysis is driven by mechanochemical coupling of subunit rotation within the enzyme with conformational changes in the three ATP binding sites. Proton translocation through the membrane-bound Fo part of ATP synthase powers a 10-step rotary motion of the ring of c subunits. This rotation is transmitted to the γ and ɛ subunits of the F1 part. Because γ and ɛ subunits rotate in 120° steps, we aim to unravel this symmetry mismatch by real time monitoring subunit rotation using single-molecule Förster resonance energy transfer (FRET). One fluorophore is attached specifically to the F1 motor, another one to the Fo motor of the liposome-reconstituted enzyme. Photophysical artifacts due to spectral fluctuations of the single fluorophores are minimized by a previously developed duty cycle-optimized alternating laser excitation scheme (DCO-ALEX). We report the detection of reversible elastic deformations between the rotor parts of Fo and F1 and estimate the maximum angular displacement during the load-free rotation using Monte Carlo simulations.

  16. Regional impact assessment of land use scenarios in developing countries using the FoPIA approach: Findings from five case studies

    NARCIS (Netherlands)

    König, H.J.; Uthes, S.; Schuler, J.; Zhen, L.; Purushothaman, S.; Suarma, U.; Sghaier, M.; Makokha, S.; Helming, K.; Sieber, S.; Chen, L.; Brouwer, F.M.; Morris, J.; Wiggering, H.

    2013-01-01

    The impact of land use changes on sustainable development is of increasing interest in many regions of the world. This study aimed to test the transferability of the Framework for Participatory Impact Assessment (FoPIA), which was originally developed in the European context, to developing

  17. A comparison of neural network-based predictions of foF2 with the IRI-2012 model at conjugate points in Southeast Asia

    Science.gov (United States)

    Wichaipanich, Noraset; Hozumi, Kornyanat; Supnithi, Pornchai; Tsugawa, Takuya

    2017-06-01

    This paper presents the development of Neural Network (NN) model for the prediction of the F2 layer critical frequency (foF2) at three ionosonde stations near the magnetic equator of Southeast Asia. Two of these stations including Chiang Mai (18.76°N, 98.93°E, dip angle 12.7°N) and Kototabang (0.2°S, 100.3°E, dip angle 10.1°S) are at the conjugate points while Chumphon (10.72°N, 99.37°E, dip angle 3.0°N) station is near the equator. To produce the model, the feed forward network with backpropagation algorithm is applied. The NN is trained with the daily hourly values of foF2 during 2004-2012, except 2009, and the selected input parameters, which affect the foF2 variability, include day number (DN), hour number (HR), solar zenith angle (C), geographic latitude (θ), magnetic inclination (I), magnetic declination (D) and angle of meridian (M) relative to the sub-solar point, the 7-day mean of F10.7 (F10.7_7), the 81-day mean of SSN (SSN_81) and the 2-day mean of Ap (Ap_2). The foF2 data of 2009 and 2013 are then used for testing the NN model during the foF2 interpolation and extrapolation, respectively. To examine the performance of the proposed NN, the root mean square error (RMSE) of the observed foF2, the proposed NN model and the IRI-2012 (CCIR and URSI options) model are compared. In general, the results show the same trends in foF2 variation between the models (NN and IRI-2012) and the observations in that they are higher during the day and lower at night. Besides, the results demonstrate that the proposed NN model can predict the foF2 values more closely during daytime than during nighttime as supported by the lower RMSE values during daytime (0.5 ≤ RMSE ≤ 1.0 for Chumphon and Kototabang, 0.7 ≤ RMSE ≤ 1.2 at Chiang Mai) and with the highest levels during nighttime (0.8 ≤ RMSE ≤ 1.5 for Chumphon and Kototabang, 1.2 ≤ RMSE ≤ 2.0 at Chiang Mai). Furthermore, the NN model predicts the foF2 values more accurately than the IRI model at the

  18. METHODS OF ORGANIZATION OF SCIENTIFIC RESEARCHES IN THE CONDITIONS OF INTRODUCTION OF COMPUTER ORIENTED FACILITIES OF STUDIES

    Directory of Open Access Journals (Sweden)

    Olga M. Naumenko

    2011-02-01

    Full Text Available In methodical recommendations shortly it is presented bases of organization and realization of scientific researches in a pedagogical college in the conditions of introduction of computer-oriented facilities of studies. A main aim is generalization of creative receptions and methods of receipt of new knowledge, realization of scientific researches, including experiments, treatment and presentation of their results. The first part is devoted to consideration of theory and methodology of process of scientific cognition, including application of laws of logic and dialectics in scientific research, basic principles of organization and realization of scientific researches and research experiments. In the second part the questions of planning of scientific researches in a pedagogical college, treatments and presentations the got results are considered.

  19. Intelligent condition monitoring method for bearing faults from highly compressed measurements using sparse over-complete features

    Science.gov (United States)

    Ahmed, H. O. A.; Wong, M. L. D.; Nandi, A. K.

    2018-01-01

    Condition classification of rolling element bearings in rotating machines is important to prevent the breakdown of industrial machinery. A considerable amount of literature has been published on bearing faults classification. These studies aim to determine automatically the current status of a roller element bearing. Of these studies, methods based on compressed sensing (CS) have received some attention recently due to their ability to allow one to sample below the Nyquist sampling rate. This technology has many possible uses in machine condition monitoring and has been investigated as a possible approach for fault detection and classification in the compressed domain, i.e., without reconstructing the original signal. However, previous CS based methods have been found to be too weak for highly compressed data. The present paper explores computationally, for the first time, the effects of sparse autoencoder based over-complete sparse representations on the classification performance of highly compressed measurements of bearing vibration signals. For this study, the CS method was used to produce highly compressed measurements of the original bearing dataset. Then, an effective deep neural network (DNN) with unsupervised feature learning algorithm based on sparse autoencoder is used for learning over-complete sparse representations of these compressed datasets. Finally, the fault classification is achieved using two stages, namely, pre-training classification based on stacked autoencoder and softmax regression layer form the deep net stage (the first stage), and re-training classification based on backpropagation (BP) algorithm forms the fine-tuning stage (the second stage). The experimental results show that the proposed method is able to achieve high levels of accuracy even with extremely compressed measurements compared with the existing techniques.

  20. Examination of Numerical Integration Accuracy and Modeling for GRACE-FO and GRACE-II

    Science.gov (United States)

    McCullough, C.; Bettadpur, S.

    2012-12-01

    As technological advances throughout the field of satellite geodesy improve the accuracy of satellite measurements, numerical methods and algorithms must be able to keep pace. Currently, the Gravity Recovery and Climate Experiment's (GRACE) dual one-way microwave ranging system can determine changes in inter-satellite range to a precision of a few microns; however, with the advent of laser measurement systems nanometer precision ranging is a realistic possibility. With this increase in measurement accuracy, a reevaluation of the accuracy inherent in the linear multi-step numerical integration methods is necessary. Two areas where this can be a primary concern are the ability of the numerical integration methods to accurately predict the satellite's state in the presence of numerous small accelerations due to operation of the spacecraft attitude control thrusters, and due to small, point-mass anomalies on the surface of the Earth. This study attempts to quantify and minimize these numerical errors in an effort to improve the accuracy of modeling and propagation of these perturbations; helping to provide further insight into the behavior and evolution of the Earth's gravity field from the more capable gravity missions in the future.

  1. An Efficient Method of Reweighting and Reconstructing Monte Carlo Molecular Simulation Data for Extrapolation to Different Temperature and Density Conditions

    KAUST Repository

    Sun, Shuyu

    2013-06-01

    This paper introduces an efficient technique to generate new molecular simulation Markov chains for different temperature and density conditions, which allow for rapid extrapolation of canonical ensemble averages at a range of temperatures and densities different from the original conditions where a single simulation is conducted. Obtained information from the original simulation are reweighted and even reconstructed in order to extrapolate our knowledge to the new conditions. Our technique allows not only the extrapolation to a new temperature or density, but also the double extrapolation to both new temperature and density. The method was implemented for Lennard-Jones fluid with structureless particles in single-gas phase region. Extrapolation behaviors as functions of extrapolation ranges were studied. Limits of extrapolation ranges showed a remarkable capability especially along isochors where only reweighting is required. Various factors that could affect the limits of extrapolation ranges were investigated and compared. In particular, these limits were shown to be sensitive to the number of particles used and starting point where the simulation was originally conducted.

  2. Optimization of conditions to extract high quality DNA for PCR analysis from whole blood using SDS-proteinase K method

    Directory of Open Access Journals (Sweden)

    Wajhul Qamar

    2017-11-01

    Full Text Available In case of studies associated with human genetics, genomics, and pharmacogenetics the genomic DNA is extracted from the buccal cells, whole blood etc. Several methods are exploited by the researchers to extract DNA from the whole blood. One of these methods, which utilizes cell lysis and proteolytic properties of sodium dodecyl sulfate (SDS and proteinase K respectively, might also be called SDS-PK method. It does not include any hazardous chemicals such as phenol or chloroform and is inexpensive. However, several researchers report the same method with different formulas and conditions. During our experiments with whole blood DNA extraction we experienced problems such as protein contamination, DNA purity and yield when followed some SDS-PK protocols reported elsewhere. A260/A280 and A260/A230 ratios along with PCR amplification give a clear idea about the procedure that was followed to extract the DNA. In an effort to increase the DNA purity from human whole blood, we pointed out some steps of the protocol that play a crucial role in determining the extraction of high quality DNA.

  3. SOLA-DF, Time-Dependent 2-D 2 Phase Flow, Eulerian Method with Various Boundary Conditions

    International Nuclear Information System (INIS)

    Hirth, C.W.; Romero, N.C.; Torrey, M.D.; Travis, J.R.

    1991-01-01

    1 - Description of problem or function: SOLA-DF is a numerical solution algorithm for gas-liquid mixture dynamics in two space dimensions and time. The two-phase system is described by a set of mixture equations plus a relation describing the relative flow of one phase with respect to the other. The algorithm contains models to represent the interphase exchange rates of mass, momentum, and energy for water system mixtures. 2 - Method of solution: SOLA-DF uses a finite-difference technique, which includes the Implicit Continuous-fluid Eulerian (ICE) method as an optional feature, to solve the drift-flux equations of two phase flow in two-dimensional plane or cylindrical coordinates. A wide variety of boundary conditions are possible, including free-slip, no-slip, specified inflow-outflow, continuative outflow, periodic, and constant pressure boundaries. Implicit pressure gradients are used to eliminate the Courant condition as a stability requirements, making the code useful at all Mach numbers. 3 - Restrictions on the complexity of the problem: Simple equation of state, relative velocity model and phase transition model are assumed. When large phase transition rates are present, because of the decoupled calculation of phase change and the pressure iteration, care must be exercised to make sure the solution is independent of the time-step

  4. Determination of turbine runner dynamic behaviour under operating condition by a two-way staggered fluid-structureinteraction method

    International Nuclear Information System (INIS)

    Dompierre, F; Sabourin, M

    2010-01-01

    This paper presents the application of the two-way fluid-structure interaction method introduced by ANSYS to calculate the dynamic behaviour of a Francis turbine runner under operating condition. This time-dependant calculation directly takes into account characteristics of the flow and particularly the pressure fluctuations caused by the rotor-stator interaction. This formulation allows the calculation of the damping forces of the whole system implicitly. Thereafter, the calculated dynamic stress can be used for a fatigue analysis. A verification of the mechanical and fluid simulations used as input for the fluid-structure interaction calculation is first performed. Subsequently, a connection of these two independent simulations is made. A validation according to the hydraulic conditions is made with the measurements from the scale model testing. Afterwards, the static displacement of the runner under the hydraulic load is compared with the results of a classical static analysis for verification purposes. Finally, the natural frequencies deduced by the post-processing of the dynamic portion of the runner displacement with respect to time are compared with the natural frequencies obtained from a classical acoustic modal analysis. All comparisons show a good agreement with experimental data or results obtained with conventional methods.

  5. Evaluation of the Ross fast solution of Richards' equation in unfavourable conditions for standard finite element methods

    International Nuclear Information System (INIS)

    Crevoisier, D.; Voltz, M.; Chanzy, A.

    2009-01-01

    Ross [Ross PJ. Modeling soil water and solute transport - fast, simplified numerical solutions. Agron J 2003;95:1352-61] developed a fast, simplified method for solving Richards' equation. This non-iterative 1D approach, using Brooks and Corey [Brooks RH, Corey AT. Hydraulic properties of porous media. Hydrol. papers, Colorado St. Univ., Fort Collins: 1964] hydraulic functions, allows a significant reduction in computing time while maintaining the accuracy of the results. The first aim of this work is to confirm these results in a more extensive set of problems, including those that would lead to serious numerical difficulties for the standard numerical method. The second aim is to validate a generalisation of the Ross method to other mathematical representations of hydraulic functions. The Ross method is compared with the standard finite element model, Hydrus-1D [Simunek J, Sejna M, Van Genuchten MTh. The HYDRUS-1D and HYDRUS-2D codes for estimating unsaturated soil hydraulic and solutes transport parameters. Agron Abstr 357; 1999]. Computing time, accuracy of results and robustness of numerical schemes are monitored in 1D simulations involving different types of homogeneous soils, grids and hydrological conditions. The Ross method associated with modified Van Genuchten hydraulic functions [Vogel T, Cislerova M. On the reliability of unsaturated hydraulic conductivity calculated from the moisture retention curve. Transport Porous Media 1988:3:1-15] proves in every tested scenario to be more robust numerically, and the compromise of computing time/accuracy is seen to be particularly improved on coarse grids. Ross method run from 1.25 to 14 times faster than Hydrus-1D. (authors)

  6. Influence of cultivation conditions, season of collection and extraction method on the content of antileishmanial flavonoids from Kalanchoe pinnata.

    Science.gov (United States)

    Muzitano, Michelle F; Bergonzi, Maria Camilla; De Melo, Giany O; Lage, Celso L S; Bilia, Anna Rita; Vincieri, Franco F; Rossi-Bergmann, Bartira; Costa, Sônia S

    2011-01-07

    Leaves from Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae) are popularly used for healing wounds. Its antileishmanial properties are established in experimental animals, and its active flavonoid components have been identified. In this study, we attempted to standardize the extract from K. pinnata leaves by evaluating the influence of season of harvest, sunlight exposure and method of extraction on antileishmanial flavonoids content. HPLC-DAD-MS was used to identify and quantify the active antileishmanial flavonoids in different extracts. ANOVA test for analyses of variance followed by the Tukey test of multiple comparisons were used in the statistical analysis. The antileishmanial potential was assessed by the activation of nitric oxide production by murine macrophage using the Griess method. We demonstrated that active flavonoids were significantly more abundant when the leaves were collected in the summer, and that aqueous extraction at 50°C allowed the highest flavonoid extraction. The benefit of sunlight exposure was confirmed in plants cultivated under direct sunlight when compared with those that grown under shade. Under sunny conditions the yield of the most active antileishmanial favonoid quercitrin was increased by 7-fold. All aqueous extracts tested were capable to enhance the macrophage nitric oxide production. However, hot aqueous extract from leaves collected in summer exhibited the higher activity, in agreement with HPLC-DAD-MS analysis tendency. In addition, with the aim of reducing the individual chemical variations of the plant constituents and optimizing the production of the active extract, it was obtained in vitro monoclonal KP specimens that were easily adapted to field conditions and were able to produce antileishmanial flavonoids. Our study reports the better conditions of cultivation, harvest and extraction protocol for obtaining a K. pinnata extract exhibiting the highest antileishmanial activity. Additionally, we propose the

  7. Citrulline protects Streptococcus pyogenes from acid stress using the arginine deiminase pathway and the F1Fo-ATPase.

    Science.gov (United States)

    Cusumano, Zachary T; Caparon, Michael G

    2015-04-01

    A common stress encountered by both pathogenic and environmental bacteria is exposure to a low-pH environment, which can inhibit cell growth and lead to cell death. One major defense mechanism against this stress is the arginine deiminase (ADI) pathway, which catabolizes arginine to generate two ammonia molecules and one molecule of ATP. While this pathway typically relies on the utilization of arginine, citrulline has also been shown to enter into the pathway and contribute to protection against acid stress. In the pathogenic bacterium Streptococcus pyogenes, the utilization of citrulline has been demonstrated to contribute to pathogenesis in a murine model of soft tissue infection, although the mechanism underlying its role in infection is unknown. To gain insight into this question, we analyzed a panel of mutants defective in different steps in the ADI pathway to dissect how arginine and citrulline protect S. pyogenes in a low-pH environment. While protection provided by arginine utilization occurred through the buffering of the extracellular environment, citrulline catabolism protection was pH independent, requiring the generation of ATP via the ADI pathway and a functional F1Fo-ATP synthase. This work demonstrates that arginine and citrulline catabolism protect against acid stress through distinct mechanisms and have unique contributions to virulence during an infection. An important aspect of bacterial pathogenesis is the utilization of host-derived nutrients during an infection for growth and virulence. Previously published work from our lab identified a unique role for citrulline catabolism in Streptococcus pyogenes during a soft tissue infection. The present article probes the role of citrulline utilization during this infection and its contribution to protection against acid stress. This work reveals a unique and concerted action between the catabolism of citrulline and the F1Fo-ATPase that function together to provide protection for bacteria in a low

  8. 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.

  9. FIELD EVALUATION OF IMPROVED METHODS FOR MEASURING THE AIR LEAKAGE OF DUCT SYSTEMS UNDER NORMAL OPERATING CONDITIONS IN 51 HOMES

    Energy Technology Data Exchange (ETDEWEB)

    Paul W. Francisco; Larry Palmiter; Erin Kruse; Bob Davis

    2003-10-18

    Duct leakage in forced-air distribution systems has been recognized for years as a major source of energy losses in residential buildings. Unfortunately, the distribution of leakage across homes is far from uniform, and measuring duct leakage under normal operating conditions has proven to be difficult. Recently, two new methods for estimating duct leakage at normal operating conditions have been devised. These are called the nulling test and the Delta-Q test. Small exploratory studies have been done to evaluate these tests, but previously no large-scale study on a broad variety of homes has been performed to determine the accuracy of these new methods in the field against an independent benchmark of leakage. This sort of study is important because it is difficult in a laboratory setting to replicate the range of leakage types found in real homes. This report presents the results of a study on 51 homes to evaluate these new methods relative to an independent benchmark and a method that is currently used. An evaluation of the benchmark procedure found that it worked very well for supply-side leakage measurements, but not as well on the return side. The nulling test was found to perform well, as long as wind effects were minimal. Unfortunately, the time and difficulty of setup can be prohibitive, and it is likely that this method will not be practical for general use by contractors except in homes with no return ducts. The Delta-Q test was found to have a bias resulting in overprediction of the leakage, which qualitatively confirms the results of previous laboratory, simulation, and small-scale field studies. On average the bias was only a few percent of the air handler flow, but in about 20% of the homes the bias was large. A primary flaw with the Delta-Q test is the assumption that the pressure between the ducts and the house remain constant during the test, as this assumption does not hold true. Various modifications to the Delta-Q method were evaluated as

  10. Standard abdominal wound edge protection with surgical dressings vs coverage with a sterile circular polyethylene drape for prevention of surgical site infections (BaFO: study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Mihaljevic André L

    2012-05-01

    Full Text Available Abstract Background Postoperative surgical site infections cause substantial morbidity, prolonged hospitalization, costs and even mortality and remain one of the most frequent surgical complications. Approximately 14% to 30% of all patients undergoing elective open abdominal surgery are affected and methods to reduce surgical site infection rates warrant further investigation and evaluation in randomized controlled trials. Methods/design To investigate whether the application of a circular plastic wound protector reduces the rate of surgical site infections in general and visceral surgical patients that undergo midline or transverse laparotomy by 50%. BaFO is a randomized, controlled, patient-blinded and observer-blinded multicenter clinical trial with two parallel surgical groups. The primary outcome measure will be the rate of surgical site infections within 45 days postoperative assessed according to the definition of the Center for Disease Control. Statistical analysis of the primary endpoint will be based on the intention-to-treat population. The global level of significance is set at 5% (2 sided and sample size (n = 258 per group is determined to assure a power of 80% with a planned interim analysis for the primary endpoint after the inclusion of 340 patients. Discussion The BaFO trial will explore if the rate of surgical site infections can be reduced by a single, simple, inexpensive intervention in patients undergoing open elective abdominal surgery. Its pragmatic design guarantees high external validity and clinical relevance. Trial registration http://www.clinicaltrials.gov NCT01181206. Date of registration: 11 August 2010; date of first patient randomized: 8 September 2010

  11. The effect of different surface conditioning methods and curing protocols on bond strengths of two different fissure sealants

    Directory of Open Access Journals (Sweden)

    Sezin Özer

    2016-01-01

    Full Text Available OBJECTIVE: To evaluate in vitro shear bond strength of two different resin-based fissure sealants [BeautiSealant (BS, UltraSeal XT hydro (UH] associated with application of an acid etching (Ultra-Etch Acid or a primer (BeautiSealant Primer and two different polymerization modes (Standard mode; 10 s or Xtra power mode; 3 s of a third generation light emitting diode (LED light curing unit. MATERIALS AND METHOD: Eighty enamel surface samples were prepared from 40 extracted human third molar teeth. Samples were randomly divided into 8 subgroups according to fissure sealants, conditioning methods and polymerization modes (n=10; Group 1: Acid + BS+ Xtra power mode, Group 2: Primer + BS + Xtra power mode, Group 3: Acid + BS + Standard mode, Group 4: Primer + BS + Standard mode, Group 5: Acid + UH + Xtra power mode, Group 6: Primer + UH + Xtra power mode, Group 7: Acid + UH + Standard mode, Group 8: Primer + UH + Standard mode. An Instron machine (1.0 mm/min was used to measure shear bond strength values. Data were statistically analyzed by using one-way ANOVA and Tukey’s test (p<0.05. RESULTS: Significant differences were detected between the groups (p<0.05. Shear bond strength values of all BS subgroups were significantly lower than UH subgroups (p<0.05. Highest shear bond strength values were obtained in Group 5 and the lowest was obtained in Group 1. CONCLUSION: Shear bond strength values of fissure sealants can be affected by surface conditioning methods and curing protocols.

  12. Comparison of microbial methods to detect fecal coliforms, E. coli and Salmonella spp. in finished compost

    Science.gov (United States)

    Introduction: Compost provides nutrients for produce crops. Improperly composted feedstocks can harbor pathogens which can be transferred to produce crops. The US Environmental Protection Agency (EPA) and US Composting Council (USCC) provide methods to test biosolids and compost, respectively, fo...

  13. Аpplying of Explosives of the Type an-fo and Slurry in the Open Pit Mine "Bucim"

    OpenAIRE

    Dambov, Risto; Nikolic, Miroslav; Dambov, Ilija

    2012-01-01

    In this paper shows the way of application of ANFO and SLURRY bulk explosives and blasting methods that are characteristic for this open pit mine. According to the physical - mechanical characteristics of the working environment and condition of the blast hole are defining some parameters for each series separately. In this open pit are defined 5(five) different working environments - rocks with copper mineralization (0,25%Cu) or rocks waste. According to the effects of blasting are make cert...

  14. Total phosphorus reference condition for subalpine lakes: a comparison among traditional methods and a new process-based watershed approach.

    Science.gov (United States)

    Salerno, Franco; Viviano, Gaetano; Carraro, Elisa; Manfredi, Emanuela Chiara; Lami, Andrea; Musazzi, Simona; Marchetto, Aldo; Guyennon, Nicolas; Tartari, Gianni; Copetti, Diego

    2014-12-01

    Different methods for estimating the total phosphorus (TP) reference conditions of lakes have rarely been compared. This work tests the uncertainty and accuracy of the most frequently used approaches (Morpho-edaphic index -MEI-, export coefficient, diatoms and pigment-inferred TP models) for 35 subalpine lakes. Furthermore, we propose a new process-based watershed approach that was tested on a subalpine environment and consists of combining a space for time substitution with a space for space substitution. The possible presence of uncontaminated or less contaminated environments inside or next to the watershed can be exploited by training a hydrological transport watershed model according to the uncontaminated conditions and then applying the calibration to the entire watershed, which reconstructs a natural or semi-natural TP load scenario. We found that the root mean square error (RMSE) for the MEI is 4 μg L(-1). However, its application is limited for lakes that present with an alkalinity ≤1 meq L(-1). For lakes with a higher alkalinity, we observed a loss of predictive capability that results from the lower solubility of phosphorus under conditions of high calcium content. The export coefficient model was applied with a mean export coefficient and presents similar prediction capabilities as the MEI. The chlorophyll-inferred TP model shows a higher uncertainty (RMSE = 8 μg L(-1)); however, it produced fewer underestimations and overestimations. With regards to the diatom-inferred TP model, we are only able to evaluate an uncertainty of 5 μg L(-1) at the European level. Finally, the proposed process-based watershed approach adequately predicted the reference condition of the selected lake and had an uncertainty lower than the other methods (2 μg L(-1)). We conclude by revealing the potential and limitations of this approach in the field of ecological lake modelling more and more attracted by TP pristine load inputs in studies on the effects of

  15. Synthesis of LiCoO2 Nanoparticles by a Sonochemical Method under the Multibubble Sonoluminescence Conditions

    International Nuclear Information System (INIS)

    Park, Jong Pil; Park, Jea Young; Hwang, Cha Hwan; Choi, Myung Ho; Kim, Jee Eon; Ok, Kang Min; Shim, Il Wun

    2010-01-01

    LiCoO 2 , a cathode material for lithium rechargeable batteries, was prepared in a nanoscale through a simple sonochemistry. First, Co 3 O 4 nanoparticles were prepared by reacting NaOH and CoCl 2 or CoSO 4 with a sonochemical method, operated at 20 kHz and 220 W for 20 min, very powerful multibubble sonoluminescence conditions for chemical reactions. Second, LiOH was coated onto the Co 3 O 4 nanoparticles by the same method as above. Finally, LiCoO 2 nanoparticles of about 10 ∼ 30 nm size in diameter were obtained by the thermal treatment of the resulting LiOH- coated Co 3 O 4 nanoparticles at 500 .deg. C for 3 hr. This synthetic process is relatively quite mild and simple compared to the known method for the synthesis of LiCoO 2 nanoparticles. The materials synthesized were characterized by infrared spectroscopy, X-ray diffraction, inductively coupled plasma spectrometer, and high resolution-transmission electron microscopy analyses

  16. The physical phenomena associated with stator winding insulation condition as detected by the ramped direct high-voltage method

    Science.gov (United States)

    Rux, Lorelynn Mary

    Deregulation of the electric utility industry has increased the need to monitor the state of powerplant equipment, such as critical generators and motors, to improve availability and reduce life cycle costs via condition-based maintenance. To achieve these goals, nondestructive condition assessment and diagnostic tests are necessary to evaluate the quality and condition of a machine's stator winding insulation system. Periodic tests are generally conducted to monitor insulation aging, diagnose problems, or provide some assurance that the winding has a minimum level of electrical strength. The basic principles of insulation testing are presented herein, and the physical mechanisms that affect the current versus voltage response are described. A stator winding insulation model was developed based on this theoretical foundation for use in understanding and analyzing the macroscopic behavior of complex insulation phenomena. A comprehensive, controlled laboratory experiment was conducted on a set of stator coils that were deliberately manufactured with and without insulation defects. Specific defects were chosen to represent the types of insulation problems typically encountered during manufacture or as a result of in-service aging, and included lack of resin cure, loosely-applied insulating tapes, internal conductive contamination, reduced density of the groundwall insulation, and thermal cycling damage. Results are presented from a series of electrical tests conducted on the coil specimens to compare the effectiveness of various test methods in detecting the different insulation problems. The tests included insulation resistance, polarization index, ramped direct voltage, dissipation factor, dielectric spectroscopy, partial discharge, and recovery voltage measurements. Dielectric principles and testing experience obtained during this investigation were applied to a collection of test results obtained by the author from in-service machines during the past ten years

  17. Comparative Study of foF2 Measurements with IRI-2007 Model Predictions During Extended Solar Minimum

    Science.gov (United States)

    Zakharenkova, I. E.; Krankowski, A.; Bilitza, D.; Cherniak, Iu.V.; Shagimuratov, I.I.; Sieradzki, R.

    2013-01-01

    The unusually deep and extended solar minimum of cycle 2324 made it very difficult to predict the solar indices 1 or 2 years into the future. Most of the predictions were proven wrong by the actual observed indices. IRI gets its solar, magnetic, and ionospheric indices from an indices file that is updated twice a year. In recent years, due to the unusual solar minimum, predictions had to be corrected downward with every new indices update. In this paper we analyse how much the uncertainties in the predictability of solar activity indices affect the IRI outcome and how the IRI values calculated with predicted and observed indices compared to the actual measurements.Monthly median values of F2 layer critical frequency (foF2) derived from the ionosonde measurements at the mid-latitude ionospheric station Juliusruh were compared with the International Reference Ionosphere (IRI-2007) model predictions. The analysis found that IRIprovides reliable results that compare well with actual measurements, when the definite (observed and adjusted) indices of solar activityare used, while IRI values based on earlier predictions of these indices noticeably overestimated the measurements during the solar minimum.One of the principal objectives of this paper is to direct attention of IRI users to update their solar activity indices files regularly.Use of an older index file can lead to serious IRI overestimations of F-region electron density during the recent extended solar minimum.

  18. Double-lock ratchet mechanism revealing the role of  SER-344 in FoF1 ATP synthase

    KAUST Repository

    Beke-Somfai, T.

    2011-03-07

    In a majority of living organisms, FoF1 ATP synthase performs the fundamental process of ATP synthesis. Despite the simple net reaction formula, ADP+Pi→ATP+H2O, the detailed step-by-step mechanism of the reaction yet remains to be resolved owing to the complexity of this multisubunit enzyme. Based on quantum mechanical computations using recent high resolution X-ray structures, we propose that during ATP synthesis the enzyme first prepares the inorganic phosphate for the γP-OADP bond-forming step via a double-proton transfer. At this step, the highly conserved αS344 side chain plays a catalytic role. The reaction thereafter progresses through another transition state (TS) having a planar ion configuration to finally form ATP. These two TSs are concluded crucial for ATP synthesis. Using stepwise scans and several models of the nucleotide-bound active site, some of the most important conformational changes were traced toward direction of synthesis. Interestingly, as the active site geometry progresses toward the ATP-favoring tight binding site, at both of these TSs, a dramatic increase in barrier heights is observed for the reverse direction, i.e., hydrolysis of ATP. This change could indicate a "ratchet" mechanism for the enzyme to ensure efficacy of ATP synthesis by shifting residue conformation and thus locking access to the crucial TSs.

  19. Fo Shou San, an ancient Chinese herbal decoction, protects endothelial function through increasing endothelial nitric oxide synthase activity.

    Directory of Open Access Journals (Sweden)

    Cathy W C Bi

    Full Text Available Fo Shou San (FSS is an ancient herbal decoction comprised of Chuanxiong Rhizoma (CR; Chuanxiong and Angelicae Sinensis Radix (ASR; Danggui in a ratio of 2:3. Previous studies indicate that FSS promotes blood circulation and dissipates blood stasis, thus which is being used widely to treat vascular diseases. Here, we aim to determine the cellular mechanism for the vascular benefit of FSS. The treatment of FSS reversed homocysteine-induced impairment of acetylcholine (ACh-evoked endothelium-dependent relaxation in aortic rings, isolated from rats. Like radical oxygen species (ROS scavenger tempol, FSS attenuated homocysteine-stimulated ROS generation in cultured human umbilical vein endothelial cells (HUVECs, and it also stimulated the production of nitric oxide (NO as measured by fluorescence dye and biochemical assay. In addition, the phosphorylation levels of both Akt kinase and endothelial NO synthases (eNOS were markedly increased by FSS treatment, which was abolished by an Akt inhibitor triciribine. Likewise, triciribine reversed FSS-induced NO production in HUVECs. Finally, FSS elevated intracellular Ca(2+ levels in HUVECs, and the Ca(2+ chelator BAPTA-AM inhibited the FSS-stimulated eNOS phosphorylation. The present results show that this ancient herbal decoction benefits endothelial function through increased activity of Akt kinase and eNOS; this effect is causally via a rise of intracellular Ca(2+ and a reduction of ROS.

  20. method

    Directory of Open Access Journals (Sweden)

    L. M. Kimball

    2002-01-01

    Full Text Available This paper presents an interior point algorithm to solve the multiperiod hydrothermal economic dispatch (HTED. The multiperiod HTED is a large scale nonlinear programming problem. Various optimization methods have been applied to the multiperiod HTED, but most neglect important network characteristics or require decomposition into thermal and hydro subproblems. The algorithm described here exploits the special bordered block diagonal structure and sparsity of the Newton system for the first order necessary conditions to result in a fast efficient algorithm that can account for all network aspects. Applying this new algorithm challenges a conventional method for the use of available hydro resources known as the peak shaving heuristic.