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Sample records for reservoirs levees channel

  1. Aggradation of Leveed Channels and Their Flood Plains in Arroyo Bottoms

    Science.gov (United States)

    Vincent, K. R.

    2005-12-01

    Many arroyos that formed by incision more than a century ago in the southwestern United States are currently filling with sediment. This reversal of processes is important because it causes changes in riparian ecology, erosion hazards, ground water recharge, and sediment supply to downstream. Along the Rio Puerco and Chaco Wash in New Mexico, we examined the geometry and facies of channel and floodplain stratigraphy exposed in trenches, used high-resolution dating of the sedimentary beds, and used photographs and other historical evidence to investigate the processes of aggradation in naturally leveed channels within arroyos. Prior to the onset of aggradation, the streambeds were composed of sand and had low relief, and arroyo walls retreated rapidly due to stream undermining. Aggradation began with the formation of sand levees at the margins of the streambeds, followed by formation of newer levees increasingly closer to the thalweg. These levees coincide with rows of woody shrubs (tamarisk and willow), plants that germinated in moist sand along the high-water marks of moderate flows, and survived because subsequent periods lacked flows large enough to remove them. Flow entering a row of woody shrubs decelerates, promoting deposition of suspended sand. Stream flows in this setting are always turbid but do not have the rheology of debris flows. The rows of shrubs probably are a requirement for initial formation of sand levees on low relief streambeds in this setting. As new levees formed closer to the thalweg the channel effectively narrowed, and smaller discharges overtopped the levees adjacent to the channel. Those closer levees accumulated sand most rapidly, leaving the suspended sand concentration depleted by the time water reached more distant ones. All levees aggraded vertically. As the main channel narrowed it acquired a roughly trapezoidal-shape (Top Width/Depth ~ 9 to 5) with banks inclined close to the angle of repose. In addition, sediment deposited on

  2. Carbonate Channel-Levee Systems Influenced by Mass-Transport Deposition, Browse Basin, Australia

    Science.gov (United States)

    Dunlap, D.; Janson, X.; Sanchez-Phelps, C.; Covault, J. A.

    2017-12-01

    Submarine channels are primary conduits for clastic sediment transport to deep-water basins, thereby controlling the location of marine depocenters and sediment bypass. The evolution and depositional character of submarine channels have broad implications to sediment dispersal, sediment quality, and hydrocarbon exploration potential. Siliciclastic channel systems have been extensively studied in modern environments, seismic and outcrop; however, carbonate channel-levee deposits have only recently been explored. Here we utilize newly released high-resolution (90 Hz) seismic-reflection data from the Australian Browse Basin to document the influence of mass-transport complex (MTC) deposition on the stratigraphic architecture of carbonate channel-levee systems. The 2014 vintage seismic survey is 2500 km2 and hosts numerous large Miocene-age carbonate channel-levee complexes basinward of the shelf edge. Regional horizons and individual channel forms were mapped. Channels range from 200-300 m wide and are bounded by high-relief levee-overbank wedges (>100 ms TWTT). These channels extend across the survey area >70 km. The leveed-channels were sourced from middle and late Miocene slope gullies linked to platform carbonates. Slope-attached and locally derived MTC's are evident throughout the Miocene section likely related to periods of basin inversion and shelf-edge gully incision. We interpret that regionally extensive (>1000 km2) slope-attached MTC's can shut down a channel-levee system and trigger the initiation of a new system, whereas more locally derived (interactions with MTC's are similar to siliciclastic analogs. The similarity in stratigraphic patterns between siliciclastic and carbonate depositional systems suggests similar formative processes related to submarine mass wasting and turbidity currents, which informs depositional models of carbonate slope systems and calls for re-evaluation of the controls on stratigraphic patterns in mixed siliciclastic

  3. Laboratory Modeling of Self-Formed Leveed Channels From Sediment-Laden Flows Entering Still Water

    Science.gov (United States)

    Rowland, J. C.; Dietrich, W. E.

    2004-12-01

    Self-formed leveed channels constructed by deposition of suspended sediment from sediment-laden flows entering still water are common features in nature. Such channels drive delta progradation, develop at tidal inlets and occur where mainstem river flows empty into oxbows and blocked valley lakes. Presently there is no theory for the formation of such channels. This lack of theory is partly due to a lack of field or laboratory studies that provide insight about the mechanism controlling these self-formed, propagating channels. The creation of such features in the laboratory, have proved illusive to date. Our ongoing experiments aimed at modeling the formation of floodplain tie channels provide insight into the necessary conditions for levee formation and channel growth. Under conditions of steady water discharge, constant sediment feed rate, unimodal sediment distribution and invariant basin stage we are able to create subaqueous lateral bars (submerged levees) along the margins of a sediment laden jet. Our results highlight the sensitivity of channel formation to issues of scaling and experimental design. In the laboratory, levee formation has only been possible with the use of plastic particles (specific gravity ~1.5); complete bed alluviation and dune formation results from the use of particles with specific gravities of ~ 2.65 across a range grain diameters and shapes. We hypothesize this effect is related to high entrainment thresholds relative to suspension thresholds of small (< 100 mm) natural particles under conditions of reduced turbulence in laboratory scaled flows. Additionally, both the width to depth ratio and the form of the outlet channel introducing the sediment laden flow into the experimental basin exert a strong control on sedimentation pattern and levee growth. Continuing experiments are focused on generating emergent channel levees and a basin ward propagation of the channel by adjusting the form of the feed channel, varying basin stage, and

  4. Burrowing activity in channel levees: impact of the invasive red swamp crayfish Procambarus clarkii

    Science.gov (United States)

    Solari, L.; Bendoni, M.; Consumi, L.; Haubrock, P.; Inghilesi, A.; Mazza, G.; Torrini, M.; Tricarico, E.

    2016-12-01

    The effect of animal burrowing, as an example of bioturbation on the stability of river levees has been recently raised to the scientific community as a consequence of the levee collapses of Secchia and Foenna rivers in Italy (Camici et al., 2010, 2014; Orlandini et al., 2015). Indeed, these authors showed that the presence of animal burrows is crucial in promoting the collapse of the bank. The American red swamp Crayfish Procambarus clarkii is an invasive species in Europe, mostly introduced for commercial purposes related to livestock. It is rapidly spreading throughout the Italian peninsula due to its plasticity, dispersal capability and high reproduction rate (Souty-Grosset et al., 2016). As well as the negative effects on local biodiversity, it damages the levees of the irrigation channel leading to disastrous collapses, relevant repairing and maintenance costs. In this work, we present an experimental activity where specimens of P. clarkii were monitored while burrowing into a small-scale physical model of an earthen levee, coupled with the mathematical modelling of the variations induced by the burrows on the seepage flow patterns through the levee.Preliminary results show the burrowing structure was quite irregular. Generally, crayfish start burrowing under the water level, developing tunnels (diameter ranging 4-7cm) both horizontally and heading upward, also above the water level. Some tunnels showed one or more circular chambers. The highest burrowing activity was observed during the experiments carried out in summer, when the species has a peak of maximum activity due to the higher temperature. Mathematical modelling shows that, for given boundary conditions and experimental duration, the presence of burrows in the levee raises the phreatic line. Critical conditions for levee integrity may be associated either to the internal erosion and stability of the system of tunnels and to the emergence of the phreatic line of the landside of the levee slope. These

  5. Sedimentological analysis and bed thickness statistics from a Carboniferous deep-water channel-levee complex: Myall Trough, SE Australia

    Science.gov (United States)

    Palozzi, Jason; Pantopoulos, George; Maravelis, Angelos G.; Nordsvan, Adam; Zelilidis, Avraam

    2018-02-01

    This investigation presents an outcrop-based integrated study of internal division analysis and statistical treatment of turbidite bed thickness applied to a Carboniferous deep-water channel-levee complex in the Myall Trough, southeast Australia. Turbidite beds of the studied succession are characterized by a range of sedimentary structures grouped into two main associations, a thick-bedded and a thin-bedded one, that reflect channel-fill and overbank/levee deposits, respectively. Three vertically stacked channel-levee cycles have been identified. Results of statistical analysis of bed thickness, grain-size and internal division patterns applied on the studied channel-levee succession, indicate that turbidite bed thickness data seem to be well characterized by a bimodal lognormal distribution, which is possibly reflecting the difference between deposition from lower-density flows (in a levee/overbank setting) and very high-density flows (in a channel fill setting). Power law and exponential distributions were observed to hold only for the thick-bedded parts of the succession and cannot characterize the whole bed thickness range of the studied sediments. The succession also exhibits non-random clustering of bed thickness and grain-size measurements. The studied sediments are also characterized by the presence of statistically detected fining-upward sandstone packets. A novel quantitative approach (change-point analysis) is proposed for the detection of those packets. Markov permutation statistics also revealed the existence of order in the alternation of internal divisions in the succession expressed by an optimal internal division cycle reflecting two main types of gravity flow events deposited within both thick-bedded conglomeratic and thin-bedded sandstone associations. The analytical methods presented in this study can be used as additional tools for quantitative analysis and recognition of depositional environments in hydrocarbon-bearing research of ancient

  6. First record of resting cysts of the benthic dinoflagellate Prorocentrum leve in a natural reservoir in Gujan-Mestras, Gironde, France.

    Science.gov (United States)

    Mertens, Kenneth Neil; Gu, Haifeng; Pospelova, Vera; Chomérat, Nicolas; Nézan, Elisabeth; Gurdebeke, Pieter Roger; Bogus, Kara; Vrielinck, Henk; Rumebe, Myriam; Meteigner, Claire

    2017-12-01

    The resting cysts of the benthic dinoflagellate Prorocentrum leve from a natural reservoir in Gujan-Mestras (Gironde, France) were described in this study. The incubated urn-shaped cysts gave rise to cells of P. leve. Morphological observations through light microscopy and scanning electron microscopy, particularly of the periflagellar platelets, combined with large subunit ribosomal DNA sequences obtained through single-cell analysis confirm their affinity to the species P. leve. The cysts were characterized by a specific shape and the presence of an anterior plug. This is the first conclusive evidence for fossilizable resting stages within the Prorocentrales, one of the major orders within the Dinophyceae. Palynological treatments show that the cysts and endospores withstand hydrochloric and hydrofluoric acids. Micro-Fourier transform infrared analysis on single specimens suggests that the composition of the endospore is cellulosic and the cyst wall a more robust, noncellulosic β-glucan. The spectra overall are similar to other published spectra of resting cysts from autotrophic, planktonic dinoflagellates. © 2017 Phycological Society of America.

  7. A complementary conventional analysis for channelized reservoirs

    International Nuclear Information System (INIS)

    Escobar Freddy Humberto; Montealegre M, Matilde

    2007-01-01

    Many well pressure data coming from long and narrow reservoirs which result from either fluvial deposition of faulting connote be completely interpreted by conventional analysis since some flow regimes are not conventionally recognized yet in the oil literature. This narrow geometry allows for the simultaneous development of two linear flow regimes coming from each one of the lateral sides of the system towards the well. This has been called dual linear flow regime. If the well is off-centered with regards to the two lateral boundaries, then, and of the linear flow regimes vanishes and, than, two possibilities con be presented. Firstly, if the closer lateral boundary is close to flow the unique linear flow persists along the longer lateral boundary. It has been called single linear flow. Following this, either steady or pseudo-steady states will develop. Secondly, if a constant - pressure closer lateral boundary is dealt with, then parabolic flow develops along the longer lateral boundary. Steady state has to be developed once the disturbance reaches the farther boundary. This study presents new equations for conventional analysis for the dual linear, linear and parabolic flow regimes recently introduced to the oil literature. The equations were validated by applying them to field and simulated examples

  8. Estimating the gas hydrate recovery prospects in the western Black Sea basin based on the 3D multiphase flow of fluid and gas components within highly permeable paleo-channel-levee systems

    Science.gov (United States)

    Burwicz, Ewa; Zander, Timo; Rottke, Wolf; Bialas, Joerg; Hensen, Christian; Atgin, Orhan; Haeckel, Matthias

    2017-04-01

    Gas hydrate deposits are abundant in the Black Sea region and confirmed by direct observations as well as geophysical evidence, such as continuous bottom simulating reflectors (BSRs). Although those gas hydrate accumulations have been well-studied for almost two decades, the migration pathways of methane that charge the gas hydrate stability zone (GHSZ) in the region are unknown. The aim of this study is to explore the most probable gas migration scenarios within a three-dimensional finite element grid based on seismic surveys and available basin cross-sections. We have used the commercial software PetroMod(TM) (Schlumberger) to perform a set of sensitivity studies that narrow the gap between the wide range of sediment properties affecting the multi-phase flow in porous media. The high-resolution model domain focuses on the Danube deep-sea fan and associated buried sandy channel-levee systems whereas the total extension of the model domain covers a larger area of the western Black Sea basin. Such a large model domain allows for investigating biogenic as well as thermogenic methane generation and a permeability driven migration of the free phase of methane on a basin scale to confirm the hypothesis of efficient methane migration into the gas hydrate reservoir layers by horizontal flow along the carrier beds.

  9. Integrating outcrop and subsurface data to assess the temporal evolution of a submarine channel-levee system

    NARCIS (Netherlands)

    Morris, Emma A.; Hodgson, David M.; Flint, Stephen; Brunt, Rufus L.; Luthi, S.M.; Kolenberg, Yolanda

    2016-01-01

    The morphological evolution of submarine channel systems can be documented using high-resolution three-dimensional seismic data sets. However, these studies provide limited information on the distribution of sedimentary facies within channel fills, channelscale stacking patterns, or the detailed

  10. Erosion of Earthen Levees by Wave Action

    Science.gov (United States)

    Ozeren, Y.; Wren, D. G.; Reba, M. L.

    2016-02-01

    Earthen levees of aquaculture and irrigation reservoirs in the United States often experience significant erosion due to wind-generated waves. Typically constructed using local soils, unprotected levees are subjected to rapid erosion and retreat due to wind generated waves and surface runoff. Only a limited amount of published work addresses the erosion rates for unprotected levees, and producers who rely on irrigation reservoirs need an economic basis for selecting a protection method for vulnerable levees. This, in turn, means that a relationship between wave energy and erosion of cohesive soils is needed. In this study, laboratory experiments were carried out in order to quantify wave induced levee erosion and retreat. A model erodible bank was packed using a soil consisting of approximately 14% sand, 73% silt, and 13% clay in a 20.6 m long 0.7 m wide and 1.2 m deep wave tank at the USDA-ARS, National Sedimentation Laboratory in Oxford MS. The geometry of the levee face was monitored by digital camera and the waves were measured by means of 6 capacitance wave staffs. Relationships were established between levee erosion, edge and retreat rates, and incident wave energy.

  11. Hydrodynamic and sedimentological controls governing formation of fluvial levees

    Science.gov (United States)

    Johnston, G. H.; Edmonds, D. A.; David, S. R.; Czuba, J. A.

    2017-12-01

    Fluvial levees are familiar features found on the margins of river channels, yet we know little about what controls their presence, height, and shape. These attributes of levees are important because they control sediment transfer from channel to floodplain and flooding patterns along a river system. Despite the familiarity and importance of levees, there is a surprising lack of basic geomorphic data on fluvial levees. Because of this we seek to understand: 1) where along rivers do levees tend to occur?; 2) what geomorphic and hydrodynamic variables control cross-sectional shape of levees? We address these questions by extracting levee shape from LiDAR data and by collecting hydrodynamic and sedimentological data from reaches of the Tippecanoe River, the White River, and the Muscatatuck River, Indiana, USA. Fluvial levees are extracted from a 1.5-m resolution LiDAR bare surface model and compared to hydrological, sedimentological, and geomorphological data from USGS stream gages. We digitized banklines and extracted levee cross-sections to calculate levee slope, taper, height, e-folding length, and e-folding width. To answer the research questions, we performed a multivariable regression between the independent variables—channel geometry, sediment grain size and concentration, flooding conditions, and slope—and the dependent levee variables. We find considerable variation in levee presence and shape in our field data. On the Muscatatuck River levees occur on 30% of the banks compared to 10% on the White River. Moreover, levees on the Muscatatuck are on average 3 times wider than the White River. This is consistent with the observation that the Muscatatuck is finer-grained compared to the White River and points to sedimentology being an important control on levee geomorphology. Future work includes building a morphodynamic model to understand how different hydrodynamic and geomorphic conditions control levee geometry.

  12. Water Age Responses to Weather Conditions in a Hyper-Eutrophic Channel Reservoir in Southern China

    Directory of Open Access Journals (Sweden)

    Wei Du

    2016-08-01

    Full Text Available Channel reservoirs have the characteristics of both rivers and lakes, in which hydrodynamic conditions and the factors affecting the eutrophication process are complex and highly affected by weather conditions. Water age at any location in the reservoir is used as an indicator for describing the spatial and temporal variations of water exchange and nutrient transport. The hyper-eutrophic Changtan Reservoir (CTR in Southern China was investigated. Three weather conditions including wet, normal, and dry years were considered for assessing the response of water age by using the coupled watershed model Soil Water Assessment Tool (SWAT and the three-dimensional hydrodynamic model Environmental Fluid Hydrodynamic Code (EFDC. The results showed that the water age in CTR varied tremendously under different weather conditions. The averaged water ages at the downstream of CTR were 3 d, 60 d, and 110 d, respectively in the three typical wet, normal, and dry years. The highest water ages at the main tributary were >70 d, >100 d, and >200 d, respectively. The spatial distribution of water ages in the tributaries and the reservoir were mainly affected by precipitation. This paper provides useful information on water exchange and transport pathways in channel reservoir, which will be helpful in understanding nutrient dynamics for controlling algal blooms.

  13. Using Levee Setbacks to Increase Floodplain Connectivity and Reduce Flood Risk

    Science.gov (United States)

    Dahl, T. A.; Echevarria-Doyle, W.

    2017-12-01

    Levees typically constrain flood flows to within the main channel, isolating the river from its natural floodplain. Levees limit the areal and temporal extents of flooding, but can increase flood peaks, alter ecosystems, and cause scour. In order to mitigate these effects, some groups have begun moving portions of levees further away from the main channel, creating setback levees. Here we describe a series of levee setback scenarios for a hypothetical river that were modeled with the unsteady, 2D-hydraulic model AdH. In our scenarios, the water surface elevations were reduced both at the location of the levee setback and for some distance upstream. The models also show that the floodplain roughness can have a greater effect on the reduction in water surface elevation than the size of the levee setback. Groups planning levee setbacks can use these results to help guide their designs.

  14. Bursting Events in Pressure Flushing with Expanding Bottom Outlet Channel within Dam Reservoir

    Directory of Open Access Journals (Sweden)

    soheila Tofighi

    2017-01-01

    Full Text Available Introduction: Currently, large dams in the world, due to the high amount of sediments in the reservoir, especially around the intake, have operational problems. One of the solutions for this problem is pressure flushing. In this type of flushing, a mixture of water and sediment is removed from bottom outlets form dam reservoir and a funnel shaped crater is created in the vicinity of the outlet opening. In laboratory experiments carried out in this study, pressure flushing with the expansion of bottom outlet within the reservoir and its statistical analysis of bursting events were investigated. The structure of the turbulent flow is not fully understood due to their complexity and random nature. Klein et al. Introduced the turbulence bursting in this kind of flow and Nezo and Nakagora suggested that the events resulting from turbulence bursting has a significant effect of transferring the sediment particles. Materials and Methods: For the purposes of this study, the experiments were conducted with a physical model with 7m length, 1.4m width, and 1.5m height, consisting of three parts namely the inlet of the model, the main reservoir, and settling basin. The main reservoir of the model was 5m long and the sediments were placed within this part of the model. The sediment particles were non-cohesive silica with uniform size and with median diameter (d50 1.15mm and geometrics standard deviation (σg 1.37. Experiments carried out with different discharges and water depths above the bottom outlet in different expansion size of outlet channel in constant sediment level of 20cm above the center of the outlet channel. The model was slowly filled with water until the water surface elevation reached to a desired level. The bottom outlet was manually opened, after a while sedimentwere discharged with the water flow in very high concentrations through the outlet channel (sudden discharge and a funnel shaped crater was formed in front of it. After the run of

  15. National Levee Database: monitoring, vulnerability assessment and management in Italy

    Science.gov (United States)

    Barbetta, Silvia; Camici, Stefania; Maccioni, Pamela; Moramarco, Tommaso

    2015-04-01

    A properly designed and constructed levees system can often be an effective device for repelling floodwaters and provide barriers against inundation to protect urbanized and industrial areas. However, the delineation of flooding-prone areas and the related hydraulic hazard mapping taking account of uncertainty (Apel et al., 2008) are usually developed with a scarce consideration of the possible occurrence of levee failures along river channels (Mazzoleni et al., 2014). Indeed, it is well known that flooding is frequently the result of levee failures that can be triggered by several factors, as: (1) overtopping, (2) scouring of the foundation, (3) seepage/piping of levee body/foundation, and (4) sliding of the foundation. Among these failure mechanisms that are influenced by the levee's geometrical configuration, hydraulic conditions (e.g. river level and seepage), and material properties (e.g. permeability, cohesion, porosity, compaction), the piping caused by seepage (ICOLD, http://www.icold-cigb.org) is considered one of the most dominant levee failure mechanisms (Colleselli F., 1994; Wallingford H. R., 2003). The difficulty of estimating the hydraulic parameters to properly describe the seepage line within the body and foundation of the levee implies that the study of the critical flood wave routing is typically carried out by assuming that the levee system is undamaged during the flood event. In this context, implementing and making operational a National Levee Database (NLD), effectively structured and continuously updated, becomes fundamental to have a searchable inventory of information about levees available as a key resource supporting decisions and actions affecting levee safety. The ItaliaN LEvee Database (INLED) has been recently developed by the Research Institute for Geo-Hydrological Protection (IRPI) for the Civil Protection Department of the Presidency of Council of Ministers. INLED has the main focus of collecting comprehensive information about

  16. Differentiating submarine channel-related thin-bedded turbidite facies: Outcrop examples from the Rosario Formation, Mexico

    Science.gov (United States)

    Hansen, Larissa; Callow, Richard; Kane, Ian; Kneller, Ben

    2017-08-01

    Thin-bedded turbidites deposited by sediment gravity flows that spill from submarine channels often contain significant volumes of sand in laterally continuous beds. These can make up over 50% of the channel-belt fill volume, and can thus form commercially important hydrocarbon reservoirs. Thin-bedded turbidites can be deposited in environments that include levees and depositional terraces, which are distinguished on the basis of their external morphology and internal architecture. Levees have a distinctive wedge shaped morphology, thinning away from the channel, and confine both channels (internal levees) and channel-belts (external levees). Terraces are flat-lying features that are elevated above the active channel within a broad channel-belt. Despite the ubiquity of terraces and levees in modern submarine channel systems, the recognition of these environments in outcrop and in the subsurface is challenging. In this outcrop study of the Upper Cretaceous Rosario Formation (Baja California, Mexico), lateral transects based on multiple logged sections of thin-bedded turbidites reveal systematic differences in sandstone layer thicknesses, sandstone proportion, palaeocurrents, sedimentary structures and ichnology between channel-belt and external levee thin-bedded turbidites. Depositional terrace deposits have a larger standard deviation in sandstone layer thicknesses than external levees because they are topographically lower, and experience a wider range of turbidity current sizes overspilling from different parts of the channel-belt. The thickness of sandstone layers within external levees decreases away from the channel-belt while those in depositional terraces are less laterally variable. Depositional terrace environments of the channel-belt are characterized by high bioturbation intensities, and contain distinctive trace fossil assemblages, often dominated by ichnofabrics of the echinoid trace fossil Scolicia. These assemblages contrast with the lower

  17. Dams and Levees: Safety Risks

    Science.gov (United States)

    Carter, N. T.

    2017-12-01

    The nation's flood risk is increasing. The condition of U.S. dams and levees contributes to that risk. Dams and levee owners are responsible for the safety, maintenance, and rehabilitation of their facilities. Dams-Of the more than 90,000 dams in the United States, about 4% are federally owned and operated; 96% are owned by state and local governments, public utilities, or private companies. States regulate dams that are not federally owned. The number of high-hazard dams (i.e., dams whose failure would likely result in the loss of human life) has increased in the past decade. Roughly 1,780 state-regulated, high-hazard facilities with structural ratings of poor or unsatisfactory need rehabilitation. Levees-There are approximately 100,000 miles of levees in the nation; most levees are owned and maintained by municipalities and agricultural districts. Few states have levee safety programs. The U.S. Army Corps of Engineers (Corps) inspects 15,000 miles of levees, including levees that it owns and local levees participating in a federal program to assist with certain post-flood repairs. Information is limited on how regularly other levees are inspected. The consequence of a breach or failure is another aspect of risk. State and local governments have significant authority over land use and development, which can shape the social and economic impacts of a breach or failure; they also lead on emergency planning and related outreach. To date, federal dam and levee safety efforts have consisted primarily of (1) support for state dam safety standards and programs, (2) investments at federally owned dams and levees, and (3) since 2007, creation of a national levee database and enhanced efforts and procedures for Corps levee inspections and assessments. In Public Law 113-121, enacted in 2014, Congress (1) directed the Corps to develop voluntary guidelines for levee safety and an associated hazard potential classification system for levees, and (2) authorized support for the

  18. At leve med osteoporose

    DEFF Research Database (Denmark)

    Hansen, Carrinna; Abrahamsen, Bo; Konradsen, Hanne

    Baggrund: Livet med kronisk sygdom, heriblandt osteoporose, giver anledning til verdensomspændende udfordringer. Osteoporose er ofte en usynlig tilstand før knoglebrud opstår, det er anslået, at hver tredje kvinde og en af fire mænd over 50 år i Europa vil opleve disse typer af knoglebrud og det...... med betydelig sygelighed og dødelighed til følge. At leve med en kronisk tilstand påvirker ofte menneskets livssituation, både specifikt, emotionelt og eksistentielt, hvordan dette opleves er individuelt og det er endnu uklart hvordan osteoporose påvirker den enkeltes livssituation. Formål: At opnå en...... dybere forståelse af livet med osteoporose ved at undersøge ny-diagnosticerede kvinders erfaringer med at leve med osteoporose når medicinsk behandling med henblik på frakturforebyggelse var ordineret. Metode: Et kvalitativt studie med en fænomenologisk-hermeneutisk tilgang, samt et longitudinelt design...

  19. Morphology of fluvial levee series along a river under human influence, Maros River, Hungary

    Science.gov (United States)

    Kiss, Tímea; Balogh, Márton; Fiala, Károly; Sipos, György

    2018-02-01

    The development and morphometry of fluvial levees reflect the connection between channel and overbank processes, which can be altered by various human activities. The aims of this study are to investigate the morphology and spatial characteristics of fluvial levees and evaluate the role of some local- and catchment-scale human activities on their medium-term (150 years) development. This study applies LiDAR data along a 53-km-long reach of the Maros River in Hungary. Six fluvial levee types are identified based on the beginning and end of their evolution. These levee types were generated by local nineteenth century channel regulation works (cutoffs) and mid-twentieth century channel narrowing, which was caused by gravel mining and water impoundment in the upstream sections. However, other human activities also influenced the development of active fluvial levees because their horizontal evolution could have been limited by embanked flood-protection levees or the widening of low-lying floodplain benches that were generated by channel narrowing. Additionally, revetment constructions influenced their vertical parameters as higher fluvial levees developed along the fixed banks. Generally, the older active fluvial levees are wider, while the younger active levees are narrower with steeper slopes but not always lower. On the low-lying floodplain levels (benches), the youngest fluvial levees evolved quite rapidly and consist of coarser material. Currently, only 9.8- to 38-year return-period floods could cover the fluvial levees, contributing to their evolution. This fact and the development of fluvial levee series with two-three members reflect a gradual decoupling of the channel from the floodplain.

  20. Bayesian networks in levee reliability

    NARCIS (Netherlands)

    Roscoe, K.; Hanea, A.

    2015-01-01

    We applied a Bayesian network to a system of levees for which the results of traditional reliability analysis showed high failure probabilities, which conflicted with the intuition and experience of those managing the levees. We made use of forty proven strength observations - high water levels with

  1. The Role of Coriolis Forces and Ekman Boundary Layers in Controlling Sediment Transport in Large Submarine Channel-Levee Systems: Experiments and Theory.

    Science.gov (United States)

    Wells, M. G.

    2016-12-01

    Large-scale oceanic flows such as contourite currents and turbidity currents can be strongly influenced by Coriolis forces. One well known consequence of Coriolis forces is the presence of Ekman boundary layers, which result in transverse secondary flows of as much as 10% of the primary flow. For flows in sinuous channels these Ekman boundary layers can either act with, or against, the secondary flows driven by centrifugal forces. These secondary flows driven by Ekman boundary layers are likely responsible for many of the details of sediment erosion and deposition in contourites, as well as in the larger channels formed by turbidity currents. The magnitude and direction of flows in the Ekman boundary layers can be defined by two Rossby numbers, RoW =U/Wf and RoR =U/Rf, where U is the mean downstream velocity, W is the width of the channel, R is the radius of curvature and f is the Coriolis parameter. Flows with Rossby numbers less than 1 are dominated by Coriolis forces and have strong Ekman boundary layers dominating secondary circulation. A new finding is that even when the Rossby number is of order 10 there is an appreciable influence of Coriolis forces. In this presentation we will present results of changes in velocity structure as a function of Rossby number from a series of analog laboratory experiments from a 1 m (Toronto) and 15 m (Grenoble) wide rotating Coriolis platform. Changes in flow structures will be related to experimental observations of changes in erosion and deposition of a mobile bed form. We will discuss the implications of these laboratory experiments for interpretation of large-scale contourite and turbidite deposits.

  2. leve a moderada

    Directory of Open Access Journals (Sweden)

    Luis Felipe Zapata

    2008-01-01

    Full Text Available La Demencia Tipo Alzheimer (DTA representa un 70% del total de demencias que afectan a las personas de edad avanzada. Es una enfermedad neurodegenerativa que ocasiona un significativo deterioro cognitivo en los pacientes e implica una incapacidad progresiva para el adecuado funcionamiento en la vida diaria. Los estudios han tenido como eje el deterioro cognitivo, principalmente los procesos de memoria que son los más dramáticos. Sólo en años recientes se ha empezado a investigar el deterioro que puede causar la enfermedad a otros niveles como en el reconocimiento de las expresiones faciales emocionales. El objetivo de la presente investigación es analizar el reconocimiento de la expresión facial emocional en pacientes con DTA frente a personas sanas y determinar si se presentan alteraciones en este tipo de reconocimiento en los pacientes con dicha demencia. PACIENTES Y MÉTODOS: se conformaron dos grupos. Uno de 22 pacientes con DTA leves y moderados y otro grupo de 22 personas sin demencia. Se aplicó el MMSE para el diagnóstico del grado de severidad de la demencia y la prueba de rostros Pofa Kit de Paul Ekman para la evaluación del reconocimiento de la expresión facial emocional. RESULTADOS: se encontraron diferencias significativas en el reconocimiento global entre el grupo control y el grupo de pacientes. La única emoción que permaneció reconocida fue la de felicidad aún en estados moderados de la enfermedad. La rabia y tristeza se vieron afectadas desde los estados leves y el reconocimiento de la expresión de miedo se alteró solo en los estados moderados de la enfermedad

  3. Levee Areas - USACE IENC

    Data.gov (United States)

    Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

  4. Sedimentation, sediment quality, and upstream channel stability, John Redmond Reservoir, east-central Kansas, 1964-2009

    Science.gov (United States)

    Juracek, Kyle E.

    2010-01-01

    A combination of available bathymetric-survey information, bottom-sediment coring, and historical streamgage information was used to investigate sedimentation, sediment quality, and upstream channel stability for John Redmond Reservoir, east-central Kansas. Ongoing sedimentation is reducing the ability of the reservoir to serve several purposes including flood control, water supply, and recreation. The total estimated volume and mass of bottom sediment deposited between 1964 and 2009 in the conservation pool of the reservoir was 1.46 billion cubic feet and 55.8 billion pounds, respectively. The estimated sediment volume occupied about 41 percent of the conservation-pool, water-storage capacity of the reservoir. Water-storage capacity in the conservation pool has been lost to sedimentation at a rate of about 1 percent annually. Mean annual net sediment deposition since 1964 in the conservation pool of the reservoir was estimated to be 1.24 billion pounds per year. Mean annual net sediment yield from the reservoir basin was estimated to be 411,000 pounds per square mile per year Information from sediment cores shows that throughout the history of John Redmond Reservoir, total nitrogen concentrations in the deposited sediment generally were uniform indicating consistent nitrogen inputs to the reservoir. Total phosphorus concentrations in the deposited sediment were more variable than total nitrogen indicating the possibility of changing phosphorus inputs to the reservoir. As the principal limiting factor for primary production in most freshwater environments, phosphorus is of particular importance because increased inputs can contribute to accelerated reservoir eutrophication and the production of algal toxins and taste-and-odor compounds. The mean annual net loads of total nitrogen and total phosphorus deposited in the bottom sediment of the reservoir were estimated to be 2,350,000 pounds per year and 1,030,000 pounds per year, respectively. The estimated mean annual

  5. A Sparse Bayesian Imaging Technique for Efficient Recovery of Reservoir Channels With Time-Lapse Seismic Measurements

    KAUST Repository

    Sana, Furrukh

    2016-06-01

    Subsurface reservoir flow channels are characterized by high-permeability values and serve as preferred pathways for fluid propagation. Accurate estimation of their geophysical structures is thus of great importance for the oil industry. The ensemble Kalman filter (EnKF) is a widely used statistical technique for estimating subsurface reservoir model parameters. However, accurate reconstruction of the subsurface geological features with the EnKF is challenging because of the limited measurements available from the wells and the smoothing effects imposed by the \\\\ell _{2} -norm nature of its update step. A new EnKF scheme based on sparse domain representation was introduced by Sana et al. (2015) to incorporate useful prior structural information in the estimation process for efficient recovery of subsurface channels. In this paper, we extend this work in two ways: 1) investigate the effects of incorporating time-lapse seismic data on the channel reconstruction; and 2) explore a Bayesian sparse reconstruction algorithm with the potential ability to reduce the computational requirements. Numerical results suggest that the performance of the new sparse Bayesian based EnKF scheme is enhanced with the availability of seismic measurements, leading to further improvement in the recovery of flow channels structures. The sparse Bayesian approach further provides a computationally efficient framework for enforcing a sparse solution, especially with the possibility of using high sparsity rates through the inclusion of seismic data.

  6. Længe leve hurraforskning?

    DEFF Research Database (Denmark)

    Skytte Gørtz, Kim Erik

    2008-01-01

    Kapitlet tager afsæt i den gældende coachforskning og problematiserer herved, hvordan og hvorvidt denne forskning kan og skal leve op til videnskabelige kriterier. På baggrund af en lang række undersøgelser af effekter af coaching gennemgås, hvilke metodiske udfordringer der opstår, hvis og såfremt...

  7. Non-Markovianity and reservoir memory of quantum channels: a quantum information theory perspective.

    Science.gov (United States)

    Bylicka, B; Chruściński, D; Maniscalco, S

    2014-07-21

    Quantum technologies rely on the ability to coherently transfer information encoded in quantum states along quantum channels. Decoherence induced by the environment sets limits on the efficiency of any quantum-enhanced protocol. Generally, the longer a quantum channel is the worse its capacity is. We show that for non-Markovian quantum channels this is not always true: surprisingly the capacity of a longer channel can be greater than of a shorter one. We introduce a general theoretical framework linking non-Markovianity to the capacities of quantum channels and demonstrate how harnessing non-Markovianity may improve the efficiency of quantum information processing and communication.

  8. 3D Seismic Stratigraphic Analysis of Gas Hydrate Bearing Turbidite Channel-Overbank System in Northern Gulf of Mexico

    Science.gov (United States)

    Santra, M.; Flemings, P. B.; Scott, E.; Meazell, K.; Petrou, E. G.

    2017-12-01

    We present a depositional model for a gas hydrate bearing deepwater channel-overbank system in Green Canyon area (around Block 955) in northern Gulf of Mexico. The gas-hydrate bearing reservoir was tested by three wells drilled in 2009 as part of the Gulf of Mexico Gas Hydrate Joint Industry Project (JIP). The same reservoir was sampled during the recent UT-GOM2-1 pressure-coring expedition. Analysis of a newly available wide-azimuth 3D seismic data shows two distinct stages of development of the channel system that significantly impacted the reservoir characteristics. The study area is located near the present-day Green Canyon reentrant, where a succession of Miocene to recent clastic sediments overlies an extensive salt diapir connected to the autochthonous level. The entire supra-salt sedimentary section is intersected by a system of large-scale normal faults formed as a result of salt movement. The channel system containing the gas hydrate reservoir has a well-defined basal surface, and is capped by a channel abandonment surface. Seismic analysis shows at least two distinct phases of channel development. In the first phase, levees undergo progressive gravitational collapse along series of normal faults that dip towards the channel axis. The normal faults on either side of channel axis are linked to a zone of compression located at the channel axis by a decollement surface at the base of the channel. The compression is recorded by bulging and/or thrusting at the channel center. This compressional bulge was eroded at the channel axis. During this phase, no axial channel deposits have been preserved. However, the position of the channel axis is indicated by a prominent linear ridge of fine-grained material that represents the remnant of the compressional bulge. Mapping of gravitational failure surfaces shows significant rotation and displacement of levee deposits along them. The second phase of development of the channel system is marked by the termination of

  9. Tree growth and recruitment in a leveed floodplain forest in the Mississippi River Alluvial Valley, USA

    Science.gov (United States)

    Gee, Hugo K.W.; King, Sammy L.; Keim, Richard F.

    2014-01-01

    Flooding is a defining disturbance in floodplain forests affecting seed germination, seedling establishment, and tree growth. Globally, flood control, including artificial levees, dams, and channelization has altered flood regimes in floodplains. However, a paucity of data are available in regards to the long-term effects of levees on stand establishment and tree growth in floodplain forests. In this study, we used dendrochronological techniques to reconstruct tree recruitment and tree growth over a 90-year period at three stands within a ring levee in the Mississippi River Alluvial Valley (MAV) and to evaluate whether recruitment patterns and tree growth changed following levee construction. We hypothesized that: (1) sugarberry is increasing in dominance and overcup oak (Quercus lyrata) is becoming less dominant since the levee, and that changes in hydrology are playing a greater role than canopy disturbance in these changes in species dominance; and (2) that overcup oak growth has declined following construction of the levee and cessation of overbank flooding whereas that of sugarberry has increased. Recruitment patterns shifted from flood-tolerant overcup oak to flood-intolerant sugarberry (Celtis laevigata) after levee construction. None of the 122 sugarberry trees cored in this study established prior to the levee, but it was the most common species established after the levee. The mechanisms behind the compositional change are unknown, however, the cosmopolitan distribution of overcup oak during the pre-levee period and sugarberry during the post-levee period, the lack of sugarberry establishment in the pre-levee period, and the confinement of overcup oak regeneration to the lowest areas in each stand after harvest in the post-levee period indicate that species-specific responses to flooding and light availability are forcing recruitment patterns. Overcup oak growth was also affected by levee construction, but in contrast to our hypothesis, growth actually

  10. Historic channel change on Esopus Creek, upstream of the Ashokan Reservoir, Catskills, New York

    Science.gov (United States)

    Miller, Nicolas Ross

    An understanding of historic channel change is fundamental to informing good stream management decisions. This study correlated the history of recent channel change on Esopus Creek in the Catskill Mountains of New York to patterns in the hydrologic record in order to understand the role of hydrologic controls on the stream's changing morphology. This study identified dynamic stream segments that have the potential to impact infrastructure and water quality in this watershed, which supplies a significant portion of New York City's drinking water. Changes in channel width, sinuosity, channel index and meander migration were obtained from quantitative analysis of aerial imagery from 1959, 1980 and 2001, along with historic topographic maps and field reconnaissance. Discharge patterns correlated with observed morphologic changes, while the role of other controlling variables such as basin and valley geography, climate, changing land use and historic channelization was explored. While there were no significant net changes in active channel width for the overall study period, overall channel width decreased between 1959 and 1980 and increased between 1980 and 2001. Reach-scale changes in channel width followed the same trend, with most reaches narrowing between 1959 and 1980 and widening between 1980 and 2001. The frequency and timing of large flow events were more significant in producing morphologic changes than the magnitude of a single event. The flood of record in 1980, which followed a 22-year hiatus in large flows, appears to have performed limited channel-width changes, while smaller magnitude but more frequent flows had much greater effects. Furthermore, time periods during which moderate flows, approximating bankfull conditions, occurred more frequently were correlated to periods of channel widening, whereas periods of less frequent moderate flows were correlated to periods of channel narrowing. Overall channel sinuosity did not change significantly over the

  11. Integrated workflow for computer assisted history matching on a channelized reservoir

    NARCIS (Netherlands)

    Peters, E.; Wilschut, F.; Leeuwenburgh, O.; Hooff, P.M.E. van

    2011-01-01

    Increasingly computer assisted techniques are used for history matching reservoir models. Such methods will become indispensable in view of the increasing amount of information generated by intelligent wells, in which case manual interpretation becomes too time consuming. Also, with the increasing

  12. Screening Mississippi River Levees Using Texture-Based and Polarimetric-Based Features from Synthetic Aperture Radar Data

    Directory of Open Access Journals (Sweden)

    Lalitha Dabbiru

    2017-03-01

    Full Text Available This article reviews the use of synthetic aperture radar remote sensing data for earthen levee mapping with an emphasis on finding the slump slides on the levees. Earthen levees built on the natural levees parallel to the river channel are designed to protect large areas of populated and cultivated land in the Unites States from flooding. One of the signs of potential impending levee failure is the appearance of slump slides. On-site inspection of levees is expensive and time-consuming; therefore, a need to develop efficient techniques based on remote sensing technologies is mandatory to prevent failures under flood loading. Analysis of multi-polarized radar data is one of the viable tools for detecting the problem areas on the levees. In this study, we develop methods to detect anomalies on the levee, such as slump slides and give levee managers new tools to prioritize their tasks. This paper presents results of applying the National Aeronautics and Space Administration (NASA Jet Propulsion Lab (JPL’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR quad-polarized L-band data to detect slump slides on earthen levees. The study area encompasses a portion of levees of the lower Mississippi River in the United States. In this paper, we investigate the performance of polarimetric and texture features for efficient levee classification. Texture features derived from the gray level co-occurrence (GLCM matrix and discrete wavelet transform were computed and analyzed for efficient levee classification. The pixel-based polarimetric decomposition features, such as entropy, anisotropy, and scattering angle were also computed and applied to the support vector machine classifier to characterize the radar imagery and compared the results with texture-based classification. Our experimental results showed that inclusion of textural features derived from the SAR data using the discrete wavelet transform (DWT features and GLCM features provided

  13. Integrated reservoir characterization of a heterogeneous channel sandstone : the Duchess Lower Manville X pool

    Energy Technology Data Exchange (ETDEWEB)

    Potocki, D.; Raychaudhuri, I.; Thorburn, L. [PanCanadian Petroleum Ltd. (Canada); Galas, C.; King, H.

    1999-01-01

    The Basal Quartz formation of the Duchess Lower Mannville X pool located in southern Alberta was characterized to determine if the reservoir was a good candidate for waterflooding. Twenty performance predictions were run. The Basal Quartz reservoir sandstones have large unanticipated intrawell and interwell variations in log derived porosity and resistivity. An extensive gas cap was also found in most of the wells. Most wells were producing with a high GOR despite the thick oil zone. It was concluded that conversion of selected wells to injection and horizontal infill wells would increase the oil recovery, but due to geological heterogeneity, the gas cap and a high in situ oil viscosity, the pool could not be considered to be a good candidate for waterflooding. 3 refs., 12 figs.

  14. National Levee Database, series information for the current inventory of the Nation's levees.

    Data.gov (United States)

    Federal Geographic Data Committee — The National Levee Database is authoritative database that describes the location and condition of the Nation’s levees. The database contains 21 feature classes...

  15. Occurrence of Vibrio cholerae in fish and water from a reservoir and a neighboring channel in Ouagadougou, Burkina Faso.

    Science.gov (United States)

    Traoré, Oumar; Martikainen, Outi; Siitonen, Anja; Traoré, Alfred S; Barro, Nicolas; Haukka, Kaisa

    2014-10-15

    Vibrio cholerae is a human pathogen and natural inhabitant of aquatic environments. In this study, we surveyed the occurrence of V. cholerae in fish harvested from a reservoir that receives discharges from the population in Ouagadougou through several channels. A total of 238 fish and 80 water samples were analyzed for the presence of V. cholerae. Altogether, 13 V. cholerae strains were isolated. They were all identified as non-O1/non-O139 V. cholerae without the ctxA gene. The strains were mostly susceptible to the antimicrobials tested. Although no strains of epidemic V. cholerae serotypes were encountered, it is important to monitor the microbiological quality of this extensively used water resource and its fish.

  16. Exploring a carbonate reef reservoir - nuclear magnetic resonance and computed microtomography confronted with narrow channel and fracture porosity

    Science.gov (United States)

    Fheed, Adam; Krzyżak, Artur; Świerczewska, Anna

    2018-04-01

    The complexity of hydrocarbon reservoirs, comprising numerous moulds, vugs, fractures and channel porosity, requires a specific set of methods to be used in order to obtain plausible petrophysical information. Both computed microtomography (μCT) and nuclear magnetic resonance (NMR) are nowadays commonly utilized in pore space investigation. The principal aim of this paper is to propose an alternative, quick and easily executable approach, enabling a thorough understanding of the complicated interiors of the carbonate hydrocarbon reservoir rocks. Highly porous and fractured Zechstein bioclastic packstones from the Brońsko Reef, located in West Poland were studied. Having examined 20 thin sections coming from two different well bores, 10 corresponding core samples were subjected to both μCT and NMR experiments. After a preliminary μCT-based image analysis, 9.4 [T] high-field zero echo time (ZTE) imaging, using a very short repetition time (RT) of 2 [μs] was conducted. Taking into consideration the risk of internal gradients' generation, the reliability of ZTE was verified by 0.6 [T] Single Point Imaging (SPI), during which such a phenomenon is much less probable. Both narrow channels and fractures of different apertures appeared to be common within the studied rocks. Their detailed description was therefore undertaken based on an additional tool - the spatially-resolved 0.05 [T] T2 profiling. According to the obtained results, ZTE seems to be especially suitable for studying porous and fractured carbonate rocks, as little disturbance to the signal appears. This can be confirmed by the SPI, indicating the negligible impact of the internal gradients on the registered ZTE images. Both NMR imaging and μCT allowed for locating the most porous intervals including well-developed mouldic porosity, as well as the contrasting impermeable structures, such as the stylolites and anhydrite veins. The 3D low-field profiling, in turn, showed the fracture aperture variations

  17. Fault features and enrichment laws of narrow-channel distal tight sandstone gas reservoirs: A case study of the Jurassic Shaximiao Fm gas reservoir in the Zhongjiang Gas Field, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Zhongping Li

    2016-11-01

    Full Text Available The Jurassic Shaximiao Fm gas reservoir in the Zhongjiang Gas Field, Sichuan Basin, is the main base of Sinopec Southwest Oil & Gas Company for gas reserves and production increase during the 12th Five-Year Plan. However, its natural gas exploration and development process was restricted severely, since the exploration wells cannot be deployed effectively in this area based on the previous gas accumulation and enrichment pattern of “hydrocarbon source fault + channel sand body + local structure”. In this paper, the regional fault features and the gas accumulation and enrichment laws were discussed by analyzing the factors like fault evolution, fault elements, fault-sand body configuration (the configuration relationship between hydrocarbon source faults and channel sand bodies, trap types, and reservoir anatomy. It is concluded that the accumulation and enrichment of the Shaximiao Fm gas reservoir in this area is controlled by three factors, i.e., hydrocarbon source, sedimentary facies and structural position. It follows the accumulation laws of source controlling region, facies controlling zone and position controlling reservoir, which means deep source and shallow accumulation, fault-sand body conductivity, multiphase channel, differential accumulation, adjusted enrichment and gas enrichment at sweet spots. A good configuration relationship between hydrocarbon source faults and channel sand bodies is the basic condition for the formation of gas reservoirs. Natural gas accumulated preferentially in the structures or positions with good fault-sand body configuration. Gas reservoirs can also be formed in the monoclinal structures which were formed after the late structural adjustment. In the zones supported by multiple faults or near the crush zones, no gas accumulation occurs, but water is dominantly produced. The gas-bearing potential is low in the area with undeveloped faults or being 30 km away from the hydrocarbon source faults. So

  18. Reservoir characterization: Evaluation for the channel deposits sequence – Upper part using scanning electron microscope (SEM and mercury injection (MICP: Case of tight reservoirs (North Sea

    Directory of Open Access Journals (Sweden)

    M.S. Benzagouta

    2015-01-01

    Accordingly, this paper presents the results of a combination of reservoir characteristics determination, the use of the SEM. petrographical investigation for the purpose of detailed examination as well as the MICP application for the physical properties appraisal. The overall will lead to better understanding of the studied section coupled to other reservoir attributes identification.

  19. Transient Seepage for Levee Engineering Analyses

    Science.gov (United States)

    Tracy, F. T.

    2017-12-01

    Historically, steady-state seepage analyses have been a key tool for designing levees by practicing engineers. However, with the advances in computer modeling, transient seepage analysis has become a potentially viable tool. A complication is that the levees usually have partially saturated flow, and this is significantly more complicated in transient flow. This poster illustrates four elements of our research in partially saturated flow relating to the use of transient seepage for levee design: (1) a comparison of results from SEEP2D, SEEP/W, and SLIDE for a generic levee cross section common to the southeastern United States; (2) the results of a sensitivity study of varying saturated hydraulic conductivity, the volumetric water content function (as represented by van Genuchten), and volumetric compressibility; (3) a comparison of when soils do and do not exhibit hysteresis, and (4) a description of proper and improper use of transient seepage in levee design. The variables considered for the sensitivity and hysteresis studies are pore pressure beneath the confining layer at the toe, the flow rate through the levee system, and a levee saturation coefficient varying between 0 and 1. Getting results for SEEP2D, SEEP/W, and SLIDE to match proved more difficult than expected. After some effort, the results matched reasonably well. Differences in results were caused by various factors, including bugs, different finite element meshes, different numerical formulations of the system of nonlinear equations to be solved, and differences in convergence criteria. Varying volumetric compressibility affected the above test variables the most. The levee saturation coefficient was most affected by the use of hysteresis. The improper use of pore pressures from a transient finite element seepage solution imported into a slope stability computation was found to be the most grievous mistake in using transient seepage in the design of levees.

  20. Visible study of water shutoff techniques for reservoirs with high permeability channels

    Science.gov (United States)

    Xin, Yanyong; Zhao, Xuan

    2017-05-01

    This paper describes a compound-linking gel system consisting of Polymer, Chromium (+3), Phenolic resin and rubber particles, which has good performance for water blocking. Indoor experiments demonstrate that the breaking through pressure of compound gel system is 4.92 MPa/m, which is much higher than 2.5-3 MPa/m of conventional, and its flooding resistance is better. The pressure of sand-pack with compound gel system reaches stability at 2.5MPa after 7PV water flooding while others stay at 1.1-1.6 MPa after 3-4PV water displacement. Visible flooding models are developed to optimize the injection volume and investigate the best location to deploy plugging agents. The results show that there is a limit on injection volume, and when it equals to 0.1-0.2 PV, the application may have economic success. For models with worm-shaped channels, the best location for plugging agents is just after “inflection point” near injecting well, which can make full use of the fluid diverting to achieve highest oil recovery.

  1. Levee Safety: Army Corps and FEMA Have Made Little Progress in Carrying Out Required Activities

    Science.gov (United States)

    2016-07-01

    removing debris and unwanted vegetation from the levees, areas adjacent to floodwalls, and channels; controlling damage caused by animals (e.g...commitment to good government is reflected in its core values of accountability, integrity, and reliability. The fastest and easiest way to obtain copies

  2. Distribution, Abundance, and Population Dynamics of Northern Squawfish, Walleye, Smallmouth Bass, and Channel Catfish in John Day Reservoir, 1986 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Beamesderfer, Raymond C.

    1987-04-01

    John Day Reservoir was sampled from 25 March to 1 September 1986 using gill nets, trap nets, boat electrofishers, hook and line, and an angler survey to collect 4945 northern squawfish Ptychocheilus oregonesis, 602 walleye Stizostedion vitreum 2894 smallmouth bass Micropterus dolomieui, and 563 channel catfish Icatalurus punctatus. Distribution, abundance and population parameters of each species were examined. One year growth, mortality, and relative year class strength was described.

  3. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin)

    Energy Technology Data Exchange (ETDEWEB)

    Andrew G. Cole; George B. Asquith; Jose I. Guzman; Mark D. Barton; Mohammad A. Malik; Shirley P. Dutton; Sigrid J. Clift

    1998-04-01

    The objective of this Class III project is to demonstrate that detailed reservoir characterization of clastic reservoirs in basinal sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover more of the original oil in place by strategic infill-well placement and geologically based enhanced oil recovery. The study focused on the Ford Geraldine unit, which produces from the upper Bell Canyon Formation (Ramsey sandstone). Reservoirs in this and other Delaware Mountain Group fields have low producibility (average recovery <14 percent of the original oil in place) because of a high degree of vertical and lateral heterogeneity caused by depositional processes and post-depositional diagenetic modification. Outcrop analogs were studied to better interpret the depositional processes that formed the reservoirs at the Ford Geraldine unit and to determine the dimensions of reservoir sandstone bodies. Facies relationships and bedding architecture within a single genetic unit exposed in outcrop in Culberson County, Texas, suggest that the sandstones were deposited in a system of channels and levees with attached lobes that initially prograded basinward, aggraded, and then turned around and stepped back toward the shelf. Channel sandstones are 10 to 60 ft thick and 300 to 3,000 ft wide. The flanking levees have a wedge-shaped geometry and are composed of interbedded sandstone and siltstone; thickness varies from 3 to 20 ft and length from several hundred to several thousands of feet. The lobe sandstones are broad lens-shaped bodies; thicknesses range up to 30 ft with aspect ratios (width/thickness) of 100 to 10,000. Lobe sandstones may be interstratified with laminated siltstones.

  4. An integrated model coupling open-channel flow, turbidity current and flow exchanges between main river and tributaries in Xiaolangdi Reservoir, China

    Science.gov (United States)

    Wang, Zenghui; Xia, Junqiang; Li, Tao; Deng, Shanshan; Zhang, Junhua

    2016-12-01

    The ever growing importance of sustainable management of reservoir sedimentation has promoted the development and applications of turbidity current models. However, there are few effective and practical models in literature for turbidity currents in a reservoir where the impounded area involves both the main river and its many tributaries. An integrated numerical model coupling open-channel flow, turbidity current and flow exchanges between main river and tributaries is proposed, which can simulate the complex flow and sediment transport in a reservoir where these three physical processes coexist. The model consists of two sets of governing equations for the open-channel flow and turbidity current, which are based on the modified St. Venant equations by taking into account the effect of lateral flow exchanges. These two sets of equations are solved in the finite volume method framework and the solutions are executed in an alternating calculation mode. Different methods are respectively proposed to calculate the discharge of flow exchange caused by free surface gradient and turbidity current intrusion. For the surface-gradient driven flow exchange, a storage cell method, which re-defines the relationship between water level and representative cross-sectional area, is used to update the water level at confluence. For the turbidity current intrusion, a discharge formula is proposed based on the analysis of the energy and momentum transformation in the intruding turbid water body. This formula differs from previous ones in that the effect of tributary bed slope is considered. Two events of water-sediment regulation conducted in the Xiaolangdi Reservoir in 2004 and 2006 were simulated to test the ability of this model. The predicted reservoir drawdown process, the turbidity current evolution and the sediment venting efficiency were in close agreement with the measurements. The necessity to couple the flow exchanges was demonstrated by comparing the performance of the

  5. Geometric modelling of channel present in reservoir petroleum using Bezier splines; Modelagem da geometria de paleocanais presentes em reservatorios petroliferos usando splines de Bezier

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Carlos Eduardo S. [Universidade Federal de Campina Grande, PB (Brazil). Programa de Recursos Humanos 25 da ANP]. E-mail: carlos@dme.ufcg.edu.br; Silva, Rosana M. da [Universidade Federal de Campina Grande, PB (Brazil). Dept. de Matematica e Estatistica]. E-mail: rosana@dme.ufcg.edu.br

    2004-07-01

    This work presents an implementation of a synthetic model of a channel found in oil reservoir. The generation these models is one of the steps to the characterization and simulation of the equal probable three-dimensional geological scenery. O implemented model was obtained from fitting techniques of geometric modeling of curves and surfaces to the geological parameters (width, thickness, sinuosity and preferential direction) that defines the form to be modeled. The parameter sinuosity is related with the parameter wave length and the local amplitude of the channel, the parameter preferential direction indicates the way of the flow and the declivity of the channel. The modeling technique used to represent the surface of the channel is the sweeping technique, the consist in effectuate a translation operation from a curve along a guide curve. The guide curve, in our implementation, was generated by the interpolation of points obtained form sampled values or simulated of the parameter sinuosity, using the cubic splines of Bezier technique. A semi-ellipse, determinate by the parameter width and thickness, representing a transversal section of the channel, is the transferred curve through the guide curve, generating the channel surface. (author)

  6. Methane hydrate reservoir model around the eastern Nankai trough area offshore Japan

    Energy Technology Data Exchange (ETDEWEB)

    Inamori, T.; Hayashi, M.; Kobayashi, T.; Shimoda, N.; Takano, O.; Takayama, T.; Fujii, T.; Saeki, T. [Japan Oil, Gas and Metals National Corp., Chiba (Japan). Dept. of Technology Research and Development

    2008-07-01

    This paper described a modelling study conducted to characterize gas hydrates in the eastern Nankai trough region near the coast of Japan. Two drilling campaigns were conducted in the region, and a total of 39 boreholes were drilled to obtain logging data. Data from exploratory wells drilled in the region were also presented. Methane hydrate-concentrated zones were delineated using seismic sequence analysis and 3-D seismic surveys. Methane hydrate-bearing sediments corresponded with turbidite sands using logging and coring data. A rock physics model was developed using data obtained from the analyses. The study showed that methane hydrate bearing-sediments near the eastern Nankai trough area are heterogenous and both vertically and horizontally complex, as the sediments were composed of turbidite sands with channel-levee and lobe systems. Sandy intervals had higher levels of methane hydrates than silty or muddy intervals. The reservoirs were divided into 3 distinct types: (1) low-saturation; (2) discontinuous high-saturation; and (3) continuous high-saturation. The reservoirs were delineated by selecting the bottom simulating reflector (BSM) as the top of the hydrate-bearing sediments for the turbidite channel-levee or lobe systems. The hydrate rock physics model was used to develop the matrix support model from the relationship between P and S wave velocities and methane hydrate saturation. 9 refs., 11 figs.

  7. 33 CFR 203.51 - Levee owner's manual.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Levee owner's manual. 203.51... Program § 203.51 Levee owner's manual. (a) Authority. In accordance with section 202(f) of Public Law 104-303, the Corps will provide a levee owner's manual to the non-Federal sponsor of all flood control...

  8. Cibola High Levee Pond annual report 2004

    Science.gov (United States)

    Mueller, Gordon A.; Carpenter, Jeanette; Marsh, Paul C.

    2005-01-01

    This represents the fourth and last annual report of a five year study investigating the early life ecology of the bonytail and razorback sucker at Cibola High Levee Pond. The work in 2004 included: telemetry studies, collection of physical water quality measurements, zooplankton samples, netting fish, the collection of scale samples for aging, predator/prey tank tests and a preliminary analysis of the data base.

  9. Traumatismo craneoencefálico leve

    Science.gov (United States)

    Ortega Zufiría, José Manuel; Prieto, Noemí Lomillos; Cuba, Bernardino Choque; Degenhardt, Martin Tamarit; Núñez, Pedro Poveda; López Serrano, María Remedios; López Raigada, Azahara Belén

    2018-01-01

    Resumen Introducción y objetivo: El TCE leve representa un problema sanitario de enorme interés debido a que un número significativo de enfermos con trauma leve desarrollará complicaciones potencialmente mortales. El objetivo de este estudio ha sido describir una serie amplia de pacientes adultos, mayores de 14 años, que sufren TCE leve, atendidos en el Hospital Universitario de Getafe, entre los años 2010 y 2015 (n = 2480), estudiar el perfil epidemiológico y analizar el diagnóstico y el tratamiento efectuados, así como establecer los principales factores pronósticos que influyen en el resultado final. Método: Se ha realizado un estudio retrospectivo, de revisión de historias clínicas, analizando los resultados con estudio estadístico bivariable y multivariable. Resultados: El TCE leve es más frecuente en varones, y el mecanismo causante más común en nuestro medio es el accidente de tráfico. Se propone un modelo de clasificación de pacientes según grupos de riesgo, que los subdivide en riesgo bajo, intermedio o alto, que se correlaciona bien con la probabilidad de desarrollar complicación intracraneal, y, consecuentemente, con el resultado final. Se discute la indicación de la radiografía simple de cráneo y de la Tomografía Computarizada (TC), así como del ingreso hospitalario para observación neurológica. Conclusiones: En este estudio, la presencia de focalidad neurológica en la exploración clínica, la edad, las alteraciones de la coagulación y la existencia de fractura en la radiografía simple se relacionan con mayor posibilidad de desarrollar lesiones traumáticas intracraneales y con peor pronóstico final. La escala de Glasgow para el Coma es deficitaria en la determinación del resultado final del paciente que sufre TCE, porque no considera variables tales como la amnesia o la pérdida de conocimiento, muy frecuentes en el traumatismo craneoencefálico leve. PMID:29430327

  10. Factors and Processes Affecting Delta Levee System Vulnerability

    Directory of Open Access Journals (Sweden)

    Steven J. Deverel

    2016-12-01

    Full Text Available doi: https://doi.org/10.15447/sfews.2016v14iss4art3We appraised factors and processes related to human activities and high water, subsidence, and seismicity. Farming and drainage of peat soils caused subsidence, which contributed to levee internal failures. Subsidence rates decreased with time, but still contributed to levee instability. Modeling changes in seepage and static slope instability suggests an increased probability of failure with decreasing peat thickness. Additional data is needed to assess the spatial and temporal effects of subsidence from peat thinning and deformation. Large-scale, state investment in levee upgrades (> $700 million since the mid-1970s has increased conformance with applicable standards; however, accounts conflict about corresponding reductions in the number of failures. Modeling and history suggest that projected increases in high-flow frequency associated with climate change will increase the rate of levee failures. Quantifying this increased threat requires further research. A reappraisal of seismic threats resulted in updated ground motion estimates for multiple faults and earthquake-occurrence frequencies. Estimated ground motions are large enough to induce failure. The immediate seismic threat, liquefaction, is the sudden loss of strength from an increase in the pressure of the pore fluid and the corresponding loss of inter-particle contact forces. However, levees damaged during an earthquake that do not immediately fail may eventually breach. Key sources of uncertainty include occurrence frequencies and magnitudes, localized ground motions, and data for liquefaction potential. Estimates of the consequences of future levee failure range up to multiple billions of dollars. Analysis of future risks will benefit from improved description of levee upgrades and strength as well as consideration of subsidence, the effects of climate change, and earthquake threats. Levee habitat ecosystem benefits in this highly

  11. Effects of lateral confinement in natural and leveed reaches of a gravel-bed river: Snake River, Wyoming, USA

    Science.gov (United States)

    Leonard, Christina M.; Legleiter, Carl; Overstreet, Brandon T.

    2017-01-01

    This study examined the effects of natural and anthropogenic changes in confining margin width by applying remote sensing techniques – fusing LiDAR topography with image-derived bathymetry – over a large spatial extent: 58 km of the Snake River, Wyoming, USA. Fused digital elevation models from 2007 and 2012 were differenced to quantify changes in the volume of stored sediment, develop morphological sediment budgets, and infer spatial gradients in bed material transport. Our study spanned two similar reaches that were subject to different controls on confining margin width: natural terraces versus artificial levees. Channel planform in reaches with similar slope and confining margin width differed depending on whether the margins were natural or anthropogenic. The effects of tributaries also differed between the two reaches. Generally, the natural reach featured greater confining margin widths and was depositional, whereas artificial lateral constriction in the leveed reach produced a sediment budget that was closer to balanced. Although our remote sensing methods provided topographic data over a large area, net volumetric changes were not statistically significant due to the uncertainty associated with bed elevation estimates. We therefore focused on along-channel spatial differences in bed material transport rather than absolute volumes of sediment. To complement indirect estimates of sediment transport derived by morphological sediment budgeting, we collected field data on bed mobility through a tracer study. Surface and subsurface grain size measurements were combined with bed mobility observations to calculate armoring and dimensionless sediment transport ratios, which indicated that sediment supply exceeded transport capacity in the natural reach and vice versa in the leveed reach. We hypothesize that constriction by levees induced an initial phase of incision and bed armoring. Because levees prevented bank erosion, the channel excavated sediment by

  12. Game Theory and Risk-Based Levee System Design

    Science.gov (United States)

    Hui, R.; Lund, J. R.; Madani, K.

    2014-12-01

    Risk-based analysis has been developed for optimal levee design for economic efficiency. Along many rivers, two levees on opposite riverbanks act as a simple levee system. Being rational and self-interested, land owners on each river bank would tend to independently optimize their levees with risk-based analysis, resulting in a Pareto-inefficient levee system design from the social planner's perspective. Game theory is applied in this study to analyze decision making process in a simple levee system in which the land owners on each river bank develop their design strategies using risk-based economic optimization. For each land owner, the annual expected total cost includes expected annual damage cost and annualized construction cost. The non-cooperative Nash equilibrium is identified and compared to the social planner's optimal distribution of flood risk and damage cost throughout the system which results in the minimum total flood cost for the system. The social planner's optimal solution is not feasible without appropriate level of compensation for the transferred flood risk to guarantee and improve conditions for all parties. Therefore, cooperative game theory is then employed to develop an economically optimal design that can be implemented in practice. By examining the game in the reversible and irreversible decision making modes, the cost of decision making myopia is calculated to underline the significance of considering the externalities and evolution path of dynamic water resource problems for optimal decision making.

  13. Application of genetic algorithms as optimization tool in the location of development wells and in the layout of the channels in locations of fluvial deposit

    International Nuclear Information System (INIS)

    Hidrobo, Eduardo Alejandro; Santos Santos, Nicolas; Perez Vega, Hector Hugo

    2005-01-01

    Optimization of the exploitation of an oil field requires implementing the most advanced techniques aimed at the increase of its production. Among them, drilling new development wells (in fill wells) stands out. Defining the most adequate location for such wells is a complex process, due to diverse geological characteristics of the reservoir, and to the high uncertainty associated to the spatial distribution of the hydrocarbon storing flow units. This article presents the development of an alternative and innovative simulation alternative, which allows locating flow channels by means of integrating geo-statistical modeling and evolutional computation. The architecture of the geological model is defined by variables, which are coded in a binary system, which represent the chromosomes of the genetic algorithm, and represent the characteristic facies of a reservoir with fluvial origin (channel sand, point bars, natural levee, crevasse splay, and flood plain shale). As the product of the genetic algorithm optimization, a facies model is obtained, in which the best channel layout is obtained within the reservoir, allowing better knowledge of the spatial distribution of flow units and the hydrocarbon accumulation zones. The correct implementation of this simulation tool facilitates the location of the most adequate sites for the implementation of in fill well drilling, new zone perforating, re-perforating programs and enhanced oil recovery process, carrying to maximization of hydrocarbon recovery factor in mature reservoirs

  14. Manage Short-term Flood Events and Long-term Water Needs via Reservoir Operation: A Risk Analysis Study

    Science.gov (United States)

    Cheng, W.; Hsu, N.; Wei, C.; Cheng, W.

    2010-12-01

    This study proposes a methodology to assess the risk of the water shortage during a drought period and the risk of the downstream over-levee flows during a flood period based on the reservoir operation rules for flood control. These rules are defined by upper limits (or flood control storage zone).Through a Monte Carlo simulation, a series of hydrographs are generated to represent the reservoir inflow during a flood period based on historic typhoon events. This series of generated hydrographs are then applied to a reservoir flood operation simulation model. The simulation model calculates the water levels of reservoir at the end of a flood period and the reservoir release during the typhoon the events. Reservoir release is used to calculate the water level at downstream control locations for evaluation of a short-term over-levee risk. The ending water level of the reservoir is used as the initial condition for a water distribution optimization model that evaluates drought conditions for long-term water supply. By applying risk analysis, an assessment is made on the risk of both the water shortage during a drought and over-levee flows during flooding seasons. Based on the results of the risk analysis, we evaluate the relationship among upper-limit sets, shortage risk, and over-levee risk and also provide reservoir operation suggestions based on the risk evaluation.

  15. Numerical Hydrodynamic Study of Hypothetical Levee Setback Scenarios

    Science.gov (United States)

    2018-01-01

    ER D C /C HL T R- 18 -1 Flood and Coastal Systems Research and Development Program Numerical Hydrodynamic Study of Hypothetical Levee...public release; distribution is unlimited. The U.S. Army Engineer Research and Development Center (ERDC) solves the...nation’s toughest engineering and environmental challenges. ERDC develops innovative solutions in civil and military engineering , geospatial sciences

  16. Sediment management for reservoir

    International Nuclear Information System (INIS)

    Rahman, A.

    2005-01-01

    All natural lakes and reservoirs whether on rivers, tributaries or off channel storages are doomed to be sited up. Pakistan has two major reservoirs of Tarbela and Managla and shallow lake created by Chashma Barrage. Tarbela and Mangla Lakes are losing their capacities ever since first impounding, Tarbela since 1974 and Mangla since 1967. Tarbela Reservoir receives average annual flow of about 62 MAF and sediment deposits of 0.11 MAF whereas Mangla gets about 23 MAF of average annual flows and is losing its storage at the rate of average 34,000 MAF annually. The loss of storage is a great concern and studies for Tarbela were carried out by TAMS and Wallingford to sustain its capacity whereas no study has been done for Mangla as yet except as part of study for Raised Mangla, which is only desk work. Delta of Tarbala reservoir has advanced to about 6.59 miles (Pivot Point) from power intakes. In case of liquefaction of delta by tremor as low as 0.12g peak ground acceleration the power tunnels I, 2 and 3 will be blocked. Minimum Pool of reservoir is being raised so as to check the advance of delta. Mangla delta will follow the trend of Tarbela. Tarbela has vast amount of data as reservoir is surveyed every year, whereas Mangla Reservoir survey was done at five-year interval, which has now been proposed .to be reduced to three-year interval. In addition suspended sediment sampling of inflow streams is being done by Surface Water Hydrology Project of WAPDA as also some bed load sampling. The problem of Chasma Reservoir has also been highlighted, as it is being indiscriminately being filled up and drawdown several times a year without regard to its reaction to this treatment. The Sediment Management of these reservoirs is essential and the paper discusses pros and cons of various alternatives. (author)

  17. Fishery and Ecological Investigations of Main Stem Levee Borrow Pits Along the Lower Mississippi River.

    Science.gov (United States)

    1984-12-01

    add to levee stability. V Levee Borra Pits 16. Borrow pits form a chain of water bodies along the riverward base of the 1600-mile main line levee...Sister Lake, Michigan, to be 86 pounds per acre based on rotenone treatment . 215. Standing stock estimates averaged 174 pounds per acre from 139

  18. Evaluation of the use of reach transmissivity to quantify leakage beneath Levee 31N, Miami-Dade County, Florida

    Science.gov (United States)

    Nemeth, Mark S.; Wilcox, Walter M.; Solo-Gabriele, Helena M.

    2000-01-01

    A coupled ground- and surface-water model (MODBRANCH) was developed to estimate ground-water flow beneath Levee 31N in Miami-Dade County, Florida, and to simulate hydrologic conditions in the surrounding area. The study included compilation of data from monitoring stations, measurement of vertical seepage rates in wetlands, and analysis of the hydrogeologic properties of the ground-water aquifer within the study area. In addition, the MODBRANCH code was modified to calculate the exchange between surface-water channels and ground water using a relation based on the concept of reach transmissivity. The modified reach-transmissivity version of the MODBRANCH code was successfully tested on three simple problems with known analytical solutions. It was also tested and determined to function adequately on one field problem that had previously been solved using the unmodified version of the software. The modified version of MODBRANCH was judged to have performed satisfactorily, and it required about 60 percent as many iterations to reach a solution. Additionally, its input parameters are more physically-based and less dependent on model-grid spacing. A model of the Levee 31N area was developed and used with the original and modified versions of MODBRANCH, which produced similar output. The mean annual modeled ground-water heads differed by only 0.02 foot, and the mean annual canal discharge differed by less than 1.0 cubic foot per second. Seepage meters were used to quantify vertical seepage rates in the Everglades wetlands area west of Levee 31N. A comparison between results from the seepage meters and from the computer model indicated substantial differences that seemed to be a result of local variations in the hydraulic properties in the topmost part of the Biscayne aquifer. The transmissivity of the Biscayne aquifer was estimated to be 1,400,000 square feet per day in the study area. The computer model was employed to simulate seepage of ground water beneath Levee 31N

  19. Reservoir management

    International Nuclear Information System (INIS)

    Satter, A.; Varnon, J.E.; Hoang, M.T.

    1992-01-01

    A reservoir's life begins with exploration leading to discovery followed by delineation of the reservoir, development of the field, production by primary, secondary and tertiary means, and finally to abandonment. Sound reservoir management is the key to maximizing economic operation of the reservoir throughout its entire life. Technological advances and rapidly increasing computer power are providing tools to better manage reservoirs and are increasing the gap between good and neutral reservoir management. The modern reservoir management process involves goal setting, planning, implementing, monitoring, evaluating, and revising plans. Setting a reservoir management strategy requires knowledge of the reservoir, availability of technology, and knowledge of the business, political, and environmental climate. Formulating a comprehensive management plan involves depletion and development strategies, data acquisition and analyses, geological and numerical model studies, production and reserves forecasts, facilities requirements, economic optimization, and management approval. This paper provides management, engineers geologists, geophysicists, and field operations staff with a better understanding of the practical approach to reservoir management using a multidisciplinary, integrated team approach

  20. APPLICATION OF INTEGRATED RESERVOIR MANAGEMENT AND RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Jack Bergeron; Tom Blasingame; Louis Doublet; Mohan Kelkar; George Freeman; Jeff Callard; David Moore; David Davies; Richard Vessell; Brian Pregger; Bill Dixon; Bryce Bezant

    2000-03-01

    Reservoir performance and characterization are vital parameters during the development phase of a project. Infill drilling of wells on a uniform spacing, without regard to characterization does not optimize development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, especially carbonate reservoirs. These reservoirs are typically characterized by: (1) large, discontinuous pay intervals; (2) vertical and lateral changes in reservoir properties; (3) low reservoir energy; (4) high residual oil saturation; and (5) low recovery efficiency. The operational problems they encounter in these types of reservoirs include: (1) poor or inadequate completions and stimulations; (2) early water breakthrough; (3) poor reservoir sweep efficiency in contacting oil throughout the reservoir as well as in the nearby well regions; (4) channeling of injected fluids due to preferential fracturing caused by excessive injection rates; and (5) limited data availability and poor data quality. Infill drilling operations only need target areas of the reservoir which will be economically successful. If the most productive areas of a reservoir can be accurately identified by combining the results of geological, petrophysical, reservoir performance, and pressure transient analyses, then this ''integrated'' approach can be used to optimize reservoir performance during secondary and tertiary recovery operations without resorting to ''blanket'' infill drilling methods. New and emerging technologies such as geostatistical modeling, rock typing, and rigorous decline type curve analysis can be used to quantify reservoir quality and the degree of interwell communication. These results can then be used to develop a 3-D simulation model for prediction of infill locations. The application of reservoir surveillance techniques to identify additional reservoir ''pay'' zones

  1. Two-point versus multiple-point geostatistics: the ability of geostatistical methods to capture complex geobodies and their facies associations—an application to a channelized carbonate reservoir, southwest Iran

    Science.gov (United States)

    Hashemi, Seyyedhossein; Javaherian, Abdolrahim; Ataee-pour, Majid; Khoshdel, Hossein

    2014-12-01

    Facies models try to explain facies architectures which have a primary control on the subsurface heterogeneities and the fluid flow characteristics of a given reservoir. In the process of facies modeling, geostatistical methods are implemented to integrate different sources of data into a consistent model. The facies models should describe facies interactions; the shape and geometry of the geobodies as they occur in reality. Two distinct categories of geostatistical techniques are two-point and multiple-point (geo) statistics (MPS). In this study, both of the aforementioned categories were applied to generate facies models. A sequential indicator simulation (SIS) and a truncated Gaussian simulation (TGS) represented two-point geostatistical methods, and a single normal equation simulation (SNESIM) selected as an MPS simulation representative. The dataset from an extremely channelized carbonate reservoir located in southwest Iran was applied to these algorithms to analyze their performance in reproducing complex curvilinear geobodies. The SNESIM algorithm needs consistent training images (TI) in which all possible facies architectures that are present in the area are included. The TI model was founded on the data acquired from modern occurrences. These analogies delivered vital information about the possible channel geometries and facies classes that are typically present in those similar environments. The MPS results were conditioned to both soft and hard data. Soft facies probabilities were acquired from a neural network workflow. In this workflow, seismic-derived attributes were implemented as the input data. Furthermore, MPS realizations were conditioned to hard data to guarantee the exact positioning and continuity of the channel bodies. A geobody extraction workflow was implemented to extract the most certain parts of the channel bodies from the seismic data. These extracted parts of the channel bodies were applied to the simulation workflow as hard data. This

  2. Experimental study on distributed optical fiber-based approach monitoring saturation line in levee engineering

    Science.gov (United States)

    Su, Huaizhi; Li, Hao; Kang, Yeyuan; Wen, Zhiping

    2018-02-01

    Seepage is one of key factors which affect the levee engineering safety. The seepage danger without timely detection and rapid response may likely lead to severe accidents such as seepage failure, slope instability, and even levee break. More than 90 percent of levee break events are caused by the seepage. It is very important for seepage behavior identification to determine accurately saturation line in levee engineering. Furthermore, the location of saturation line has a major impact on slope stability in levee engineering. Considering the structure characteristics and service condition of levee engineering, the distributed optical fiber sensing technology is introduced to implement the real-time observation of saturation line in levee engineering. The distributed optical fiber temperature sensor system (DTS)-based monitoring principle of saturation line in levee engineering is investigated. An experimental platform, which consists of DTS, heating system, water-supply system, auxiliary analysis system and levee model, is designed and constructed. The monitoring experiment of saturation line in levee model is implemented on this platform. According to the experimental results, the numerical relationship between moisture content and thermal conductivity in porous medium is identified. A line heat source-based distributed optical fiber method obtaining the thermal conductivity in porous medium is developed. A DTS-based approach is proposed to monitor the saturation line in levee engineering. The embedment pattern of optical fiber for monitoring saturation line is presented.

  3. Sedimentological Characterization of a Deepwater Methane Hydrate Reservoir in Green Canyon 955, Northern Gulf of Mexico

    Science.gov (United States)

    Meazell, K.; Flemings, P. B.

    2017-12-01

    Grain size is a controlling factor of hydrate saturation within a Pleistocene channel-levee system investigated by the UT-GOM2-1 expedition within the deepwater northern Gulf of Mexico. Laser diffraction and settling experiments conducted on sediments from 413-440 meters below the seafloor reveal the presence of two interbedded lithologic units, identified as a silty sand and a clayey silt, according Shepard's classification system. The sand-rich lithofacies has low density and high p-wave velocity, suggesting a high degree of hydrate saturation. Conversely, the clay and silt dominated lithofacies is characterized by a higher density and low p-wave velocity, suggesting low hydrate saturation. The sand-rich lithofacies is well-sorted and displays abundant ripple lamination, indicative of deposition within a high-energy environment. The clayey-silt is poorly-sorted and lacks sedimentary structures. The two lithofacies are interbedded throughout the reservoir unit; however, the relative abundance of the sand-rich lithofacies increases with depth, suggesting a potential decrease in flow energy or sediment flux over time, resulting in the most favorable reservoir properties near the base of the unit.

  4. New Orleans Levees and Floodwalls: Hurricane Damage Protection

    National Research Council Canada - National Science Library

    Carter, Nicole T

    2005-01-01

    .... The breaches occurred at the Lake Pontchartrain and Vicinity Project being constructed by the U.S. Army Corps of Engineers and maintained by local levee districts. Those observers questioning why infrastructure providing a greater level of hurricane protection was not available are countered by those arguing that structural protections carry their own risks. This report will be updated as needed to track significant developments.

  5. Risk Analysis of Extreme Rainfall Effects on the Shihmen Reservoir

    Science.gov (United States)

    Ho, Y.; Lien, W.; Tung, C.

    2009-12-01

    Typhoon Morakot intruded Taiwan during 7th and 8th of August 2009, brought about 2,700 mm of total rainfall which caused serious flood and debris to the southern region of Taiwan. One of the serious flooded areas is in the downstream of Zengwen reservoir. People believed that the large amount of floodwater released from Zengwen reservoir led to the severe inundation. Therefore, the Shihmen reservoir is one of the important reservoirs in northern Taiwan. The Taipei metropolis, which is in downstream of Shihmen reservoir, is the political and economical center of Taiwan. If heavy rainfall as those brought by Typhoon Marakot falls in the Shihmen reservoir watershed, it may create a bigger disaster. This study focused on the impacts of a typhoon, like Morakot, in Shihmen reservoir. The hydrological model is used to simulate the reservoir inflows under different rainfall conditions. The reservoir water balance model is developed to calculate reservoir’s storage and outflows under the inflows and operational rules. The ability of flood mitigation is also evaluated. Besides, the released floodwater from reservoir and the inflows from different tributaries are used to determine whether or not the river stage will overtop levee. Also, the maximum released floodwater and other inflows which could lead to damages will be stated. Lastly, the criteria of rainfall conditions and initial stages of reservoir will be analyzed in this study.

  6. Computer simulations of channel meandering and the formation of point bars: Linking channel dynamics to the preserved stratigraphy

    Science.gov (United States)

    Sun, T.; Covault, J. A.; Pyrcz, M.; Sullivan, M.

    2012-12-01

    Meandering rivers are probably one of the most recognizable geomorphic features on earth. As they meander across alluvial and delta plains, channels migrate laterally and develop point bars, splays, levees and other geomorphic and sedimentary features that compose substantial portions of the fill within many sedimentary basins. These basins can include hydrocarbon producing fields. Therefore, a good understanding of the processes of meandering channels and their associated deposits is critical for exploiting these reservoirs in the subsurface. In the past couple of decades, significant progress has been made in our understanding of the morphodynamics of channel meandering. Basic fluid dynamics and sediment transport (Ikeda and Parker, 1981; Howard, 1992) has shown that many characteristic features of meandering rivers, such as the meandering wavelength, growth rate and downstream migration rate, can be predicted quantitatively. As a result, a number of variations and improvement of the theory have emerged (e.g., Blondeaux and Seminara, 1985; Parker and Andrews, 1985, 1986; and Sun et al., 2001a, b).The main improvements include the recognition of so called "bar-bend" interactions, where the development of bars on the channel bed and their interactions with the channel bend is recognized as a primary cause for meandering channels to develop greater complexity than the classic goose-neck meander bend shapes, such as compound bend. Recently, Sun and others have shown that the spatial patterns of width variations in meandering channels can be explained by an extrinsic periodic flow variations coupled with the intrinsic bend instability dynamics. In contrast to the significant improvement of our understanding of channel meandering, little work has been done to link the geomorphic features of meandering channels to the geometry and heterogeneity of the deposits they form and ultimately preserves. A computer simulation model based on the work of Sun and others (1996, 2001

  7. Lidar-based mapping of flood control levees in south Louisiana

    Science.gov (United States)

    Thatcher, Cindy A.; Lim, Samsung; Palaseanu-Lovejoy, Monica; Danielson, Jeffrey J.; Kimbrow, Dustin R.

    2016-01-01

    Flood protection in south Louisiana is largely dependent on earthen levees, and in the aftermath of Hurricane Katrina the state’s levee system has received intense scrutiny. Accurate elevation data along the levees are critical to local levee district managers responsible for monitoring and maintaining the extensive system of non-federal levees in coastal Louisiana. In 2012, high resolution airborne lidar data were acquired over levees in Lafourche Parish, Louisiana, and a mobile terrestrial lidar survey was conducted for selected levee segments using a terrestrial lidar scanner mounted on a truck. The mobile terrestrial lidar data were collected to test the feasibility of using this relatively new technology to map flood control levees and to compare the accuracy of the terrestrial and airborne lidar. Metrics assessing levee geometry derived from the two lidar surveys are also presented as an efficient, comprehensive method to quantify levee height and stability. The vertical root mean square error values of the terrestrial lidar and airborne lidar digital-derived digital terrain models were 0.038 m and 0.055 m, respectively. The comparison of levee metrics derived from the airborne and terrestrial lidar-based digital terrain models showed that both types of lidar yielded similar results, indicating that either or both surveying techniques could be used to monitor geomorphic change over time. Because airborne lidar is costly, many parts of the USA and other countries have never been mapped with airborne lidar, and repeat surveys are often not available for change detection studies. Terrestrial lidar provides a practical option for conducting repeat surveys of levees and other terrain features that cover a relatively small area, such as eroding cliffs or stream banks, and dunes.

  8. Diabetes tipo 2 y obesidad leve: tratamiento quirúrgico

    OpenAIRE

    Lanzaren S,Enrique

    2013-01-01

    Introducción: En la actualidad la diabetes mellitus tipo 2 (DM2) y la obesidad representan un serio problema de salud, comportándose como enfermedades epidémicas. Existe un gran interés en explorar distintas opciones de tratamiento de la DM2 en pacientes que no tienen obesidad mórbida. Objetivo: Reportar los parámetros de control glicémico en pacientes con DM2 y obesidad leve sometidos a bypass gástrico (BPG) a 3 años de seguimiento. Metodología: Estudio clínico prospectivo que incluye pacien...

  9. Å leve et menneskeverdig liv - Martha Nussbaums globale helseetikk

    OpenAIRE

    Odin Lysaker

    2015-01-01

    Nylig igangsatte FN Post-2015, sin nye utviklingsagenda. Sentralt er en global kamp for bedret helse, hvor det å leve et menneskeverdig liv står i sentrum. Imidlertid er forståelsen av selve helsebegrepet omstridt. Noen mener at det bør knyttes an til jus og menneskerettigheter, mens andre foreslår etikk og menneskeverd. Dette hviler i sin tur på motstridende menneskesyn i den globale helseetiske diskursen, nemlig mennesket som enten autonomt eller avhengig. I artikkelen analyserer jeg denne ...

  10. Morphodynamics of submarine channel inception revealed by new experimental approach.

    Science.gov (United States)

    de Leeuw, Jan; Eggenhuisen, Joris T; Cartigny, Matthieu J B

    2016-03-21

    Submarine channels are ubiquitous on the seafloor and their inception and evolution is a result of dynamic interaction between turbidity currents and the evolving seafloor. However, the morphodynamic links between channel inception and flow dynamics have not yet been monitored in experiments and only in one instance on the modern seafloor. Previous experimental flows did not show channel inception, because flow conditions were not appropriately scaled to sustain suspended sediment transport. Here we introduce and apply new scaling constraints for similarity between natural and experimental turbidity currents. The scaled currents initiate a leveed channel from an initially featureless slope. Channelization commences with deposition of levees in some slope segments and erosion of a conduit in other segments. Channel relief and flow confinement increase progressively during subsequent flows. This morphodynamic evolution determines the architecture of submarine channel deposits in the stratigraphic record and efficiency of sediment bypass to the basin floor.

  11. Behaviour of levee on softsoil caused by rapid drawdown

    Science.gov (United States)

    Upomo, Togani Cahyadi; Effendi, Mahmud Kori; Kusumawardani, Rini

    2018-03-01

    Rapid Drawdown is a condition where the water elevation that has reached the peak suddenly drops. As the water level reaches the peak, hydrostatic pressure helps in the stability of the slope. When water elevation decreases there will be two effects. First, reduced hydrostatic pressure and second, modification of pore water pressure. Rapid draw down usually comon in hydraulic structure such as dam and levee. This study will discuss behaviour of levee on softsoil caused by rapid drawdown. The analysis based on method which developed by US Army Corps Engineer and modified method which developed by Duncan, Wright, dan Wong. Results of analysis show that in drawdown condition, at 1 m drop of water, safety factor obtained based on US Army Corps Engineer method was 1.16 and 0.976 while based on Duncan, Wright, and Wong methods were 1.244 and 1.117. At 0.5 m water level, safety factor based on US Army Corps Engineer method was 1.287 and 1.09 while Duncan, Wright, and Wong were 1.357 and 1.194.

  12. Uso del tratamiento acupuntural en pacientes con episodio depresivo leve

    Directory of Open Access Journals (Sweden)

    Roberto Anselmo Ramos Valverde

    2014-08-01

    Full Text Available Se realizó un estudio experimental en el Centro Comunitario Provincial de Salud Mental de Las Tunas, con el objetivo de determinar la efectividad del empleo de la acupuntura en pacientes portadores de episodio depresivo leve. El universo estuvo constituido por todos los pacientes diagnosticados clínicamente con la enfermedad, que acudieron a la consulta de Medicina Natural y Tradicional de esta entidad entre marzo de 2011 a marzo de 2013. La muestra quedó constituida por 60 pacientes que cumplieron los criterios diagnósticos y de inclusión establecidos para la investigación, se aplicó un muestreo aleatorio simple que permitió conformar dos grupos, uno de estudio, al que se le aplicó tratamiento acupuntural, y uno control, que recibió tratamiento con amitriptilina. Los resultados mostraron que el insomnio fue el síntoma asociado más frecuente. Al terminar el tratamiento se obtuvo que la depresión se eliminó en la totalidad de los pacientes, pero fue más inmediato el efecto antidepresivo en los pacientes del grupo estudio, los síntomas asociados desaparecieron en casi la totalidad de ellos. Se concluye que el tratamiento tradicional acupuntural constituye una terapia efectiva en los pacientes con episodio depresivo leve

  13. Slope Instability of the Earthen Levee in Boston, UK: Numerical Simulation and Sensor Data Analysis

    NARCIS (Netherlands)

    Melnikova, N.B.; Jordan, D.; Krzhizhanovskaya, V.V.; Sloot, P.M.A.

    2014-01-01

    The paper presents a slope stability analysis for a heterogeneous earthen levee in Boston, UK, which is prone to occasional slope failures under tidal loads. Dynamic behavior of the levee under tidal fluctuations was simulated using a finite element model of variably saturated linear elastic

  14. Natural levee evolution in the Rhine-Meuse delta, the Netherlands, during the first millennium CE

    NARCIS (Netherlands)

    Pierik, H.J.; Stouthamer, E.; Cohen, K.M.

    2017-01-01

    This paper presents reconstructions on natural levee development in the Rhine-Meuse delta, the Netherlands, during the first millennium CE, covering the full delta plain. It is the first study that performs this on a delta scale, which allows seeing the delta-wide trends on levee-forming controls

  15. An assessment of two methods for identifying undocumented levees using remotely sensed data

    Science.gov (United States)

    Czuba, Christiana R.; Williams, Byron K.; Westman, Jack; LeClaire, Keith

    2015-01-01

    Many undocumented and commonly unmaintained levees exist in the landscape complicating flood forecasting, risk management, and emergency response. This report describes a pilot study completed by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers to assess two methods to identify undocumented levees by using remotely sensed, high-resolution topographic data. For the first method, the U.S. Army Corps of Engineers examined hillshades computed from a digital elevation model that was derived from light detection and ranging (lidar) to visually identify potential levees and then used detailed site visits to assess the validity of the identifications. For the second method, the U.S. Geological Survey applied a wavelet transform to a lidar-derived digital elevation model to identify potential levees. The hillshade method was applied to Delano, Minnesota, and the wavelet-transform method was applied to Delano and Springfield, Minnesota. Both methods were successful in identifying levees but also identified other features that required interpretation to differentiate from levees such as constructed barriers, high banks, and bluffs. Both methods are complementary to each other, and a potential conjunctive method for testing in the future includes (1) use of the wavelet-transform method to rapidly identify slope-break features in high-resolution topographic data, (2) further examination of topographic data using hillshades and aerial photographs to classify features and map potential levees, and (3) a verification check of each identified potential levee with local officials and field visits.

  16. Channel systems and lobe construction in the Mississippi Fan

    Science.gov (United States)

    Garrison, L. E.; Kenyon, Neil H.; Bouma, A.H.

    1982-01-01

    Morphological features on the Mississippi Fan in the eastern Gulf of Mexico were mapped using GLORIA II, a long-range side-scan sonar system. Prominent is a sinuous channel flanked by well-developed levees and occasional crevasse splays. The channel follows the axis and thickest part of the youngest fan lobe; seismic-reflection profiles offer evidence that its course has remained essentially constant throughout lobe development. Local modification and possible erosion of levees by currents indicates a present state of inactivity. Superficial sliding has affected part of the fan lobe, but does not appear to have been a factor in lobe construction. ?? 1982 A. M. Dowden, Inc.

  17. Uncertainty and Expert Assessment for Supporting Evaluation of Levees Safety

    Directory of Open Access Journals (Sweden)

    Hathout Michel

    2016-01-01

    Full Text Available In France, levees remain most of the time badly maintained; these long linear structures show signs of weaknesses on numerous occasions. Only incomplete information is usually available. The general lack of data describing the behavior of the infrastructure during unwanted events led to estimate their safety mainly from expert judgment. Thus the ability of the expert to predict the level of functioning of an infrastructure for a type of hazard and its intensity is crucial. An error of judgment can have very serious consequences and the production of reliable information requires the ability of the expert to report accurately the uncertainties in its estimations, as well as associated confidence. In order to meet this need, our research within Incertu project (French Ministry of Ecology funding aims to produce relevant scientific approaches and tools for the collection and processing reliable experts’ statements or combined with a confidence level in the context of uncertain information and input data.

  18. Terrestrial Lidar Datasets of New Orleans, Louisiana, Levee Failures from Hurricane Katrina, August 29, 2005

    Science.gov (United States)

    Collins, Brian D.; Kayen, Robert; Minasian, Diane L.; Reiss, Thomas

    2009-01-01

    Hurricane Katrina made landfall with the northern Gulf Coast on August 29, 2005, as one of the strongest hurricanes on record. The storm damage incurred in Louisiana included a number of levee failures that led to the inundation of approximately 85 percent of the metropolitan New Orleans area. Whereas extreme levels of storm damage were expected from such an event, the catastrophic failure of the New Orleans levees prompted a quick mobilization of engineering experts to assess why and how particular levees failed. As part of this mobilization, civil engineering members of the United States Geological Survey (USGS) performed terrestrial lidar topographic surveys at major levee failures in the New Orleans area. The focus of the terrestrial lidar effort was to obtain precise measurements of the ground surface to map soil displacements at each levee site, the nonuniformity of levee height freeboard, depth of erosion where scour occurred, and distress in structures at incipient failure. In total, we investigated eight sites in the New Orleans region, including both earth and concrete floodwall levee breaks. The datasets extend from the 17th Street Canal in the Orleans East Bank area to the intersection of the Gulf Intracoastal Waterway (GIWW) with the Mississippi River Gulf Outlet (MRGO) in the New Orleans East area. The lidar scan data consists of electronic files containing millions of surveyed points. These points characterize the topography of each levee's postfailure or incipient condition and are available for download through online hyperlinks. The data serve as a permanent archive of the catastrophic damage of Hurricane Katrina on the levee systems of New Orleans. Complete details of the data collection, processing, and georeferencing methodologies are provided in this report to assist in the visualization and analysis of the data by future users.

  19. Transient Flow through an Unsaturated Levee Embankment during the 2011 Mississippi River Flood

    Science.gov (United States)

    Jafari, N.; Stark, T.; Vahedifard, F.; Cadigan, J.

    2017-12-01

    The Mississippi River and corresponding tributaries drain approximately 3.23 million km2 (1.25 million mi2) or the equivalent of 41% of the contiguous United States. Approximately 2,600 km ( 1,600 miles) of earthen levees presently protect major urban cities and agricultural land against the periodic Mississippi River floods within the Lower Mississippi River Valley. The 2011 flood also severely stressed the levees and highlighted the need to evaluate the behavior of levee embankments during high water levels. The performance of earthen levees is complex because of the uncertainties in construction materials, antecedent moisture contents, hydraulic properties, and lack of field monitoring. In particular, calibration of unsaturated and saturated soil properties of levee embankment and foundation layers along with the evaluation of phreatic surface during high river stage is lacking. Due to the formation of sand boils at the Duncan Point Levee in Baton Rouge, LA during the 2011 flood event, a reconnaissance survey was conducted to collect pore-water pressures in the sand foundation using piezometers and identifying the phreatic surface at the peak river level. Transient seepage analyses were performed to calibrate the foundation and levee embankment material properties using field data collected. With this calibrated levee model, numerical experiments were conducted to characterize the effects of rainfall intensity and duration, progression of phreatic surface, and seasonal climate variability prior to floods on the performance of the levee embankment. For example, elevated phreatic surface from river floods are maintained for several months and can be compounded with rainfall to lead to slope instability.

  20. Natural levee evolution in the Rhine-Meuse delta, the Netherlands, during the first millennium CE

    Science.gov (United States)

    Pierik, H. J.; Stouthamer, E.; Cohen, K. M.

    2017-10-01

    This paper presents reconstructions on natural levee development in the Rhine-Meuse delta, the Netherlands, during the first millennium CE, covering the full delta plain. It is the first study that performs this on a delta scale, which allows seeing the delta-wide trends on levee-forming controls and their feedbacks. We mapped the levee morphology and elevation by combining LiDAR imagery, lithological borehole data, soil mapping, radiocarbon dates, archaeological data, and GIS-reconstruction techniques. From the detailed levee reconstructions we quantified natural levee dimensions and evaluated the temporal changes therein. The dimensions and the changes therein were then linked to external forcings (increasing suspended sediment load, variable flooding intensity) and to natural preconditions (e.g., delta plain width, flood basin configuration). We show that natural preconditions are an important control on levee shape. This is demonstrated for the upper delta where the relatively narrow delta plain combined with strong compartmentation (i.e., the occurrence of many alluvial ridges and enclosed flood basins) caused the flood levels to be amplified allowing the natural levees to grow relatively high. Compartmentation also seems to have stimulated trapping of coarse-grained overbank sediments, explaining the clear downstream trend in levee width. This effect was probably further aided by the clearance of the riparian forests, mainly in the upstream and central delta, which caused the coarser fraction of the suspended load to be further dispersed into the flood basin leading to wider levees. In the first millennium CE several new river courses formed that avoided the areas of natural levee relief of abandoned alluvial ridges. On these fossil alluvial ridges, the topographical expression gradually reduced because of widespread flood basin trapping of overbank sediment, which led to topographic levelling. The natural levees that formed during this period along the new

  1. 2005 United States Army Corps of Engineers (USACE) Post-Hurricane Katrina Levee Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These topographic data were collected for the U.S. Army Corps of Engineers by a helicopter-mounted LiDAR sensor over the New Orleans Hurricane Protection Levee...

  2. Guidelines for Installation of Utilities Beneath Corps of Engineers Levees Using Horizontal Directional Drilling

    National Research Council Canada - National Science Library

    Latorre, Carlos

    2002-01-01

    ... of proposed drilling for infrastructure modifications and installation of utilities. Critical considerations include setback distances, levee toe stability, thickness and integrity of the top stratum, and other geotechnical parameters...

  3. Possible Weakening Processes Imposed on California's Earthen Levees under Protracted Drought

    Science.gov (United States)

    Robinson, J. D.; Vahedifard, F.; AghaKouchak, A.

    2015-12-01

    California is currently suffering from a multiyear extreme drought and the impacts of the drought are anticipated to worsen in a warming climate. The resilience of critical infrastructure under extreme drought conditions is a major concern which has not been well understood. Thus, there is a crucial need to improve our understanding about the potential threats of drought on infrastructure and take subsequent actions in a timely manner to mitigate these threats and adopt our infrastructure for forthcoming extreme events. The need is more pronounced for earthen levees, since their functionality to protect limited water resources and dryland is more critical during drought. A significant amount of California's levee systems are currently operating under a high risk condition. Protracted drought can further threaten the structural competency of these already at-risk levee systems through several thermo-hydro mechanical weakening processes that undermine their stability. Viable information on the implications of these weakening processes, particularly on California's earthen levees, is relatively incomplete. This article discusses, from a geotechnical engineering perspective, how California's protracted drought might threaten the integrity of levee systems through the imposition of several thermo-hydro mechanical weakening processes. Pertinent facts and statistics regarding the drought in California are presented and discussed. Catastrophic levee failures and major damages resulting from drought-induce weakening processes such as shear strength reduction, desiccation cracking, land subsidence and surface erosion, fissuring and soil softening, and soil carbon oxidation are discussed to illustrate the devastating impacts that the California drought might impose on existing earthen levees. This article calls for further research in light of these potential drought-inducing weakening mechanisms to support mitigation strategies for reducing future catastrophic levee failures.

  4. Levee Vertical Land Motion Changes in the Sacramento-San Joaquin Delta

    Science.gov (United States)

    Telling, J. W.; Brooks, B. A.; Glennie, C. L.; Ericksen, T. L.; Knowles, N.

    2017-12-01

    The Sacramento-San Joaquin Delta is home to numerous islands that provide economically and agriculturally important land. However, the island interiors are sinking and most sit below sea level, making the levee roads that surround the islands vital for their continued health and productivity. Airborne LiDAR (Light Detection and Ranging) data over the islands was collected in 2007 by the California Department of Water Resources and mobile LiDAR data was collected along the levee roads on Bacon, Bouldin, Jersey, and Brannan-Andrus Islands in 2015 and 2016 by the USGS. These datasets provide high resolution topographic models with 8 year separation that can be used to examine topographic change along the levees. A cross-section of each dataset was output along the approximate centerline of the levee road, so that profiles of the 2007 and 2015/2016 LiDAR observations could be compared. Regions of levee road subsidence and of levee road construction and reinforcement on the order of 0-3 centimeters per year were evident in locations around the islands. There is a high degree of spatial variability of these rates even for individual islands. These results were compared to the levee road maps published by the CA Delta Stewardship Council and it was found that the regions of reinforcement and subsidence did not always align between the published maps and the LiDAR data. Additionally, the levee road heights and rates of change, in regions of road subsidence, were compared to sea level rise projections to evaluate the risk that rising sea level may pose to the islands in the future.

  5. Application of GPR Method for Detection of Loose Zones in Flood Levee

    Science.gov (United States)

    Gołębiowski, Tomisław; Małysa, Tomasz

    2018-02-01

    In the paper the results of non-invasive georadar (GPR) surveys carried out for detection of loose zones located in the flood levee was presented. Terrain measurements were performed on the Vistula river flood levee in the village of Wawrzeńczyce near Cracow. In the investigation site, during the flood in 2010, leakages of levee were observed, so detection of inner water filtration paths was an important matter taking into account the stability of the levee during the next flood. GPR surveys had reconnaissance character, so they were carried out with the use of short-offset reflection profiling (SORP) technique and radargrams were subjected to standard signal processing. The results of surveys allowed to outline main loose zone in the levee which were the reason of leakages in 2010. Additionally gravel interbeddings in sand were detected which had an important influence, due to higher porosity of such zones, to water filtration inside of the levee. In the paper three solutions which allow to increase quality and resolution of radargrams were presented, i.e. changeable-polarisation surveys, advanced signal processing and DHA procedure.

  6. Levee Seepage Detection in the Sacramento-San Joaquin Delta Using Polarimetric SAR

    Science.gov (United States)

    An, K.; Jones, C. E.; Bekaert, D. P.

    2017-12-01

    The Sacramento-San Joaquin Delta's extensive levee system protects over 2,800 km2 of reclaimed lands and serves as the main irrigation and domestic water supply for the state of California. However, ongoing subsidence and disaster threats from floods and earthquakes make the Delta levee system highly vulnerable, endangering water supplies for 23 million California residents and 2.5 million acres of agricultural land. Levee failure in the Delta can cause saltwater intrusion from San Francisco Bay, reducing water quality and curtailing water exports to residents, commercial users, and farmers. To protect the Delta levee system, it is essential to search for signs of seepage in which water is piping through or beneath levees, which can be associated with deformation of the levees themselves. Until now, in-situ monitoring has largely been applied, however, this is a time-consuming and expensive approach. We use data acquired with NASA's UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) airborne radar instrument to identify and characterize levee seepages and associated land subsidence through advanced remote sensing technologies. The high spatial resolution of UAVSAR can help to direct surveys to areas that are likely to be experiencing damage. UAVSAR is an L-band airborne sensor with high signal-to-noise ratio, repeat flight track accuracy, and spatial resolution of 7x7 m2 (for multi-looked products) that is necessary for detailed levee monitoring. The adaptability of radar instruments in their ability to see through smoke, haze, and clouds during the day or night, is especially relevant during disaster events, when cloud cover or lack of solar illumination inhibits traditional visual surveys of damage. We demonstrate the advantages of combining polarimetric radar imagery with geographic information systems (GIS) datasets in locating seepage features along critical levee infrastructure in the Delta for 2009-2016. The ability to efficiently locate potential

  7. Å leve et menneskeverdig liv - Martha Nussbaums globale helseetikk

    Directory of Open Access Journals (Sweden)

    Odin Lysaker

    2015-11-01

    Full Text Available Nylig igangsatte FN Post-2015, sin nye utviklingsagenda. Sentralt er en global kamp for bedret helse, hvor det å leve et menneskeverdig liv står i sentrum. Imidlertid er forståelsen av selve helsebegrepet omstridt. Noen mener at det bør knyttes an til jus og menneskerettigheter, mens andre foreslår etikk og menneskeverd. Dette hviler i sin tur på motstridende menneskesyn i den globale helseetiske diskursen, nemlig mennesket som enten autonomt eller avhengig. I artikkelen analyserer jeg denne debatten ut fra det jeg hevder er Martha Nussbaums globale helseetikk, som baseres på hennes kapabilitetstilnærming så vel som begrep om ‘helse som livskvalitet’. Min konklusjon er at Nussbaums normative begrunnelse for Post-2015 ut fra et kroppslig forankret menneskeverd er det mest overbevisende av de to konkurrerende svarene.Nøkkelord: global helseetikk, Martha Nussbaum, menneskeverd, menneskerettigheter, post-2015English summary: Living a dignified life - Martha Nussbaum's global health ethicsThe UN recently launched Post-2015, which is its new development agenda. Central here is the global struggle for improved health, in which what it takes to live a dignified life is stressed. However, the understanding of the notion of health is disputed. Some believe that it should be linked to law and the human rights, while others suggest ethics and human dignity. Which in turn rests on conflicting stands in the global health ethical discourse regards to the view of humanity, namely either as autonomous or dependent. In the paper I analyse this discourse, in which my point of departure is Martha Nussbaum’s capabilities approach as well as her concept of health as life quality. This I read exactly as a global health ethics. Thus, I conclude that between the two competing answers, Nussbaum’s normative justification for Post-2015 on the basis of bodily grounded human dignity is the most convincing.Keywords: global health ethics, Martha Nussbaum

  8. Geophysical characterization of the Lollie Levee near Conway, Arkansas, using capacitively coupled resistivity, coring, and direct push logging

    Science.gov (United States)

    Gillip, Jonathan A.; Payne, Jason

    2011-01-01

    A geophysical characterization of Lollie Levee near Conway, Arkansas, was conducted in February 2011. A capacitively coupled resistivity survey (using Geometric's OhmMapper) was completed along the top and toe of the 6.7-mile levee. Two-dimensional inversions were conducted on the geophysical data. As a quality-control measure, cores and direct push logs were taken at approximately 1-mile intervals along the levee. The capacitively coupled resistivity survey, the coring, and the direct push logs were used to characterize the geologic materials. Comparison of the cores and the direct push log data, along with published resistivity values, indicates that resistivity values of 200 Ohm-meters or greater represent relatively clean sand, with decreasing resistivity values occurring with increasing silt and clay content. The cores indicated that the levee is composed of a heterogeneous mixture of sand, silt, and clay. The capacitively coupled resistivity sections confirm that the levee is composed of a heterogeneous mixture of high and low resistivity materials and show that the composition of the levee varies spatially. The geologic materials underlying the levee vary spatially as a result of the geologic processes that deposited them. In general, the naturally deposited geologic materials underlying the levee contain a greater amount of low resistivity materials in the southern extent of the levee.

  9. Report on Levee Failures and Distress San Jacinto River Levee and Bautista Creek Channel, Riverside County, Santa Ana River Basin, California

    Science.gov (United States)

    1980-08-01

    tied, gabion stabilizers. Seven stabilizers were constructed and strengthened 7 during the period from 1969 to 1978. Flood History Major floods Major... watershed for a period of 9 consecutive days, from 13 to 21 February 1980. The daily precipitation for seven stations in or near the project area is

  10. Proceedings of the Repair, Evaluation, Maintenance, and Rehabilitation Research Program Workshop on Levee Rehabilitation Held at Vicksburg, Mississippi on 17 March 1992

    Science.gov (United States)

    1994-08-01

    a a a 0 0.2 0.4 0.6 0.8 1.0 1.2 CSR Figure 22. Liquefaction assessment, east levee, reach a, boring SL-7-90, column B 35 Seismic Assessment ot Pajero ...A Photos of Damage and Repair San Lorenzo River Levees and Pajaro River Levees Seismic Assessment of Pajero and San Lorenzo River Levees 45 211ý a...Assessment of Pajero and Sen Lorenzo River Levees , ,’i ’ ’’- a. Damage at drainage structure, left bank levee (looking upstream) .IS b. Damage to

  11. California Levee Risk, Now and in the Future:Identifying Research and Tool Development Needs

    Energy Technology Data Exchange (ETDEWEB)

    Newmark, R L; Hanemann, M; Farber, D

    2006-11-28

    The Center for Catastrophic Risk Management (CCRM) and the California Center for Environmental Law and Policy (CCELP) at UC Berkeley and the Lawrence Livermore National Laboratory (LLNL) joined together to cosponsor a workshop to define research requirements to mitigate the hazards facing the Sacramento-San Joaquin Delta Levee system. The Workshop was intended to provide a forum to (1) Report assessments of current vulnerabilities facing the levees, such as structural failure, seismic loading, flooding, terrorism; (2) Consider longer term challenges such as climate change, sea level rise; and (3) Define research requirements to fill gaps in knowledge and reduce uncertainties in hazard assessments.

  12. Experience of using FEM for real-time flood early warning systems: Monitoring and modeling Boston levee instability

    NARCIS (Netherlands)

    Melnikova, N.B.; Jordan, D.; Krzhizhanovskaya, V.V.

    2015-01-01

    Boston levee has a documented history of slope slippages under tidal fluctuations reaching 6-m range on spring tides. A finite element model of the Boston levee has been developed in the off-line mode; after that, it was integrated into the common information space of the UrbanFlood early warning

  13. Channelling and channelling radiation

    International Nuclear Information System (INIS)

    Soerensen, A.H.; Uggerhoej, E.

    1987-01-01

    The study of channelling phenomena has developed rapidly since the early 1960s and today channelling has found many applications. The radiation emitted by channelled megaelectronvolt and gigaelectronvolt electrons and positrons has been investigated extensively and the possibility of, for example, constructing intense tunable X- and γ-ray sources is being explored. Multi-gigaelectronvolt radiation and pair-creation processes in single crystals show similarities with strong-field effects and are of particular interest because of high production rates that persist far beyond the channelling regime. (author)

  14. Propriedades espectrais da matéria orgânica leve-livre e leve intra-agregado de dois latossolos sob plantio direto e preparo convencional

    Directory of Open Access Journals (Sweden)

    A. A. Freixo

    2002-06-01

    Full Text Available Este trabalho teve como objetivo estudar a natureza química das frações leves-livres (FLL e leves intra-agregado (FLI da matéria orgânica do solo, obtidas pelo fracionamento físico do solo por densidade, por meio da espectroscopia na região do infravermelho, para verificar se tais frações constituem compartimentos distintos da matéria orgânica do solo. Foram analisadas amostras de Latossolos de dois estados do Brasil (RS e GO, submetidos a plantio direto e preparo convencional, em distintos sistemas de rotação de culturas. A análise por infravermelho revelou diferenças contrastantes entre os compartimentos orgânicos estudados. Os espectros de IV da fração leve-livre apresentaram configuração semelhante aos dos resíduos vegetais, indicando que ela se encontra em estádios iniciais de transformação. Não foram observadas diferenças estruturais na FLL entre os distintos sistemas de preparo e rotação de culturas. Os espectros de IV da FLI apresentaram bandas de absorção N-H e C-O de polissacarídeos menos intensas e em maior conjugação, em relação aos espectros da FLL, características de material mais humificado. Foi observada ainda uma maior transformação estrutural da fração leve intra-agregado em solos sob preparo convencional, quando comparada à FLI de solo sob vegetação natural e plantio direto. Os índices de hidrofobicidade (IH e de condensação (IC, determinados a partir de relações entre as bandas de absorção de grupamentos - CH3 alifáticos, C-O de polissacarídeos e C=O conjugados, permitiram identificar as diferenças na recalcitrância e condensação das frações leves. Constatou-se que ambos os índices foram significativamente maiores para a matéria orgânica intra-agregado, por conseqüência de seu maior grau de humificação.

  15. Reservoir fisheries of Asia

    International Nuclear Information System (INIS)

    Silva, S.S. De.

    1990-01-01

    At a workshop on reservoir fisheries research, papers were presented on the limnology of reservoirs, the changes that follow impoundment, fisheries management and modelling, and fish culture techniques. Separate abstracts have been prepared for three papers from this workshop

  16. Large reservoirs: Chapter 17

    Science.gov (United States)

    Miranda, Leandro E.; Bettoli, Phillip William

    2010-01-01

    Large impoundments, defined as those with surface area of 200 ha or greater, are relatively new aquatic ecosystems in the global landscape. They represent important economic and environmental resources that provide benefits such as flood control, hydropower generation, navigation, water supply, commercial and recreational fisheries, and various other recreational and esthetic values. Construction of large impoundments was initially driven by economic needs, and ecological consequences received little consideration. However, in recent decades environmental issues have come to the forefront. In the closing decades of the 20th century societal values began to shift, especially in the developed world. Society is no longer willing to accept environmental damage as an inevitable consequence of human development, and it is now recognized that continued environmental degradation is unsustainable. Consequently, construction of large reservoirs has virtually stopped in North America. Nevertheless, in other parts of the world construction of large reservoirs continues. The emergence of systematic reservoir management in the early 20th century was guided by concepts developed for natural lakes (Miranda 1996). However, we now recognize that reservoirs are different and that reservoirs are not independent aquatic systems inasmuch as they are connected to upstream rivers and streams, the downstream river, other reservoirs in the basin, and the watershed. Reservoir systems exhibit longitudinal patterns both within and among reservoirs. Reservoirs are typically arranged sequentially as elements of an interacting network, filter water collected throughout their watersheds, and form a mosaic of predictable patterns. Traditional approaches to fisheries management such as stocking, regulating harvest, and in-lake habitat management do not always produce desired effects in reservoirs. As a result, managers may expend resources with little benefit to either fish or fishing. Some locally

  17. 75 FR 6364 - Process for Requesting a Variance From Vegetation Standards for Levees and Floodwalls

    Science.gov (United States)

    2010-02-09

    ... to reflect organizational changes and incorporate current agency-wide review processes. DATES... provides a clearly defined process to implement Section 202(g) of WRDA 1996. 5. Definition of a Levee... Regional Integration Team (RIT) process, for an Agency Technical Review (ATR). d. The ATR leader shall...

  18. 44 CFR 65.10 - Mapping of areas protected by levee systems.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Mapping of areas protected by... IDENTIFICATION AND MAPPING OF SPECIAL HAZARD AREAS § 65.10 Mapping of areas protected by levee systems. (a... (especially in constricted areas); expected wind and wave action; ice loading; impact of debris; slope...

  19. Finite element analysis of levee stability for flood early warning systems

    NARCIS (Netherlands)

    Melnikova, N.B.

    2014-01-01

    Floods are common natural disasters frequently taking their dramatic toll in global warming conditions. Hundreds and thousands kilometres of sensor-monitored flood protection barriers are built at the coastlines all over the world. The power of computational science helps levee maintainers in

  20. The use of seismic tomograms for the identification of internal problems with earthen dams and levees

    Science.gov (United States)

    According to the National Inventory of dams (NID, 2009), out of the 84,134 dams in the US, more than 87% (73,423) are earthen dams. The majority of these earthen dams are past or approaching their design life expectancy of 50 years. According to the National committee on Levee Safety (NCLS, 2009),...

  1. Red River of the North Walsh and Pembina Countries, North Dakota Farmstead Ring Levees.

    Science.gov (United States)

    1983-12-01

    resource needs in the metro - politan area. Farmstead ring N/A Assesses the potential Ongoing. levee analysis for Federal involve- ment in developing...sites. C-2-4 AW31ID11 C 7TCICAL XFOUKATIOU CTIOE 3 gEooEics SCT =u 3 TABM OF CWKT Item Paso INTRODUCTION C-3-1 ECONOMIC CHARACTERISTICS C-3-2 Population

  2. Leve de Variatie! Een onderzoek naar de beleving van en de publiciteit rondom Oktober Kennismaand 2010

    NARCIS (Netherlands)

    van der Veer, C.G.; Groven, M.; Higler, L.

    2011-01-01

    Leve de Variatie! Een onderzoek naar de beleving van en de publiciteit rondom Oktober Kennismaand 2010 The until 2007 yearly organized Science Week aimed at the enhancement of the knowledge of scientific and technological developments by the public has from 2008 on developed into a month of

  3. Aquatic Biological Inventory, Hillview Drainage and Levee District, Greene and Scott Counties, Illinois.

    Science.gov (United States)

    1982-01-11

    alkalinity, acidity, temperature and salinity . The 24 Yi - COE-HAS-S.I/DISC4.8 1/09/82 phytoplankton taxa collected in the Hillview Drainage and Levee...Amphipoda Gammarus pseudolimnaeus 148 3.61 Ephemeroptera Baetis app 210 5.12 Trichoptera Hydropsychidae 1,055 25.73 Hydropsyche bettani 97 2.37

  4. ON LAND SLIDE DETECTION USING TERRASAR-X OVER EARTHEN LEVEES

    Directory of Open Access Journals (Sweden)

    M. Mahrooghy

    2012-08-01

    Full Text Available Earthen levees have an important role to protect large areas of inhabited and cultivated land in the US from flooding. Failure of the levees can threaten the loss of life and property. One of the problems which can lead to a complete failure during a high water event is a slough slide. In this research, we are trying to detect such slides using X-band SAR data. Our methodology consists of the following four steps: 1 segmentation of the levee area from background; 2 extracting features including backscatter features and texture features; 3 training a back propagation neural network classifier using ground-truth data; and 4 testing the area of interest and validation of the results using ground truth data. A dual-polarimetric X-band image is acquired from the German TerraSAR-X satellite. Ground-truth data include the slides and healthy area. The study area is an approximately 1 km stretch of levee along the lower Mississippi River in the United States. The output classification shows the two classes of healthy and slide areas. The results show classification accuracies of approximately 67% for detecting the slide pixels.

  5. Geophysical investigation of a dutch levee and canal using various seismic and GPR techniques

    NARCIS (Netherlands)

    Noorlandt, R.P.; Kleine, M.P.E. de; Kruiver, P.P.; Bakker, M.A.J.; Mesdag, C.S.; Hoogendoorn, R.M.

    2011-01-01

    A geophysical survey has been carried out on the Juliana Canal and levee in the south of the Netherlands. For a stretch of about 35 km along this canal various construction works are planned, to deepen and widen the canal. The canal is in a geological setting such that leakage from the canal to the

  6. Developments in Levee Reliability and Flood Risk Analysis in the Netherlands

    NARCIS (Netherlands)

    Jonkman, S.N.; Schweckendiek, T.

    2015-01-01

    This paper presents and overview of advances in flood risk and levee reliability analysis in the Netherlands. It is described how new safety standards – in the form of a target failure probability – have been derived on the basis of nationwide flood risk assessments which taken into account both

  7. Kommunen er død - længe leve den digitale disruption

    DEFF Research Database (Denmark)

    Andersen, Kim Normann

    2017-01-01

    "New Public Management is Dead. Long Live the Digital Era." Sådan proklamerede Patrick Donleavy digitaliseringens muligheder i en banebrydende artikel fra 2005. Med en omskrivning af dette citat til "Kommunen er død, længe leve den digitale disruption", er ballet åbnet for denne artikel....

  8. Numerical modelling of levee stability based on coupled mechanical, thermal and hydrogeological processes

    Directory of Open Access Journals (Sweden)

    Dwornik Maciej

    2016-01-01

    Full Text Available The numerical modelling of coupled mechanical, thermal and hydrogeological processes for a soil levee is presented in the paper. The modelling was performed for a real levee that was built in Poland as a part of the ISMOP project. Only four parameters were changed to build different flood waves: the water level, period of water increase, period of water decrease, and period of low water level after the experiment. Results of numerical modelling shows that it is possible and advisable to calculate simultaneously changes of thermal and hydro-mechanical fields. The presented results show that it is also possible to use thermal sensors in place of more expensive pore pressure sensors, with some limitations. The results of stability analysis show that the levee is less stable when the water level decreases, after which factor of safety decreases significantly. For all flooding wave parameters described in the paper, the levee is very stable and factor of safety variations for any particular stage were not very large.

  9. ENHANCING HSPF MODEL CHANNEL HYDRAULIC REPRESENTATION

    Science.gov (United States)

    The Hydrological Simulation Program - FORTRAN (HSPF) is a comprehensive watershed model, which employs depth-area-volume-flow relationships known as hydraulic function table (FTABLE) to represent stream channel cross-sections and reservoirs. An accurate FTABLE determination for a...

  10. Grain-size segregation and levee formation in geophysical mass flows

    Science.gov (United States)

    Johnson, C.G.; Kokelaar, B.P.; Iverson, Richard M.; Logan, M.; LaHusen, R.G.; Gray, J.M.N.T.

    2012-01-01

    Data from large-scale debris-flow experiments are combined with modeling of particle-size segregation to explain the formation of lateral levees enriched in coarse grains. The experimental flows consisted of 10 m3 of water-saturated sand and gravel, which traveled ∼80 m down a steeply inclined flume before forming an elongated leveed deposit 10 m long on a nearly horizontal runout surface. We measured the surface velocity field and observed the sequence of deposition by seeding tracers onto the flow surface and tracking them in video footage. Levees formed by progressive downslope accretion approximately 3.5 m behind the flow front, which advanced steadily at ∼2 m s−1during most of the runout. Segregation was measured by placing ∼600 coarse tracer pebbles on the bed, which, when entrained into the flow, segregated upwards at ∼6–7.5 cm s−1. When excavated from the deposit these were distributed in a horseshoe-shaped pattern that became increasingly elevated closer to the deposit termination. Although there was clear evidence for inverse grading during the flow, transect sampling revealed that the resulting leveed deposit was strongly graded laterally, with only weak vertical grading. We construct an empirical, three-dimensional velocity field resembling the experimental observations, and use this with a particle-size segregation model to predict the segregation and transport of material through the flow. We infer that coarse material segregates to the flow surface and is transported to the flow front by shear. Within the flow head, coarse material is overridden, then recirculates in spiral trajectories due to size-segregation, before being advected to the flow edges and deposited to form coarse-particle-enriched levees.

  11. Stream, Lake, and Reservoir Management.

    Science.gov (United States)

    Dai, Jingjing; Mei, Ying; Chang, Chein-Chi

    2017-10-01

    This review on stream, lake, and reservoir management covers selected 2016 publications on the focus of the following sections: Stream, lake, and reservoir management • Water quality of stream, lake, and reservoirReservoir operations • Models of stream, lake, and reservoir • Remediation and restoration of stream, lake, and reservoir • Biota of stream, lake, and reservoir • Climate effect of stream, lake, and reservoir.

  12. Status of Wheeler Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of status reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Wheeler Reservoir summarizes reservoir purposes and operation, reservoir and watershed characteristics, reservoir uses and use impairments, and water quality and aquatic biological conditions. The information presented here is from the most recent reports, publications, and original data available. If no recent data were available, historical data were summarized. If data were completely lacking, environmental professionals with special knowledge of the resource were interviewed. 12 refs., 2 figs.

  13. The formation and maintenance of single-thread tie channels entering floodplain lakes: observations from three diverse river systems

    Energy Technology Data Exchange (ETDEWEB)

    Rowland, Joel C [Los Alamos National Laboratory; Dietrich, William E [UC BERKELEY; Day, Geoff [NEWCREST MINING; Parker, Gary [UNIV OF ILLINOIS

    2009-01-01

    Tie channels connect rivers to floodplain lakes on many lowland rivers and thereby play a central role in floodplain sedimentology and ecology, yet they are generally unrecognized and little studied. here we report the results of field studies focused on tie channel origin and morphodynamics in three contrasting systems: the Middle Fly River, Papua New Guinea, the Lower Mississippi River, and Birch Creek in Alaska. Across these river systems, tie channels vary by an order of magnitude in size but exhibit the same characteristic morphology and appear to develop and evolve by a similar set of processes. In all three systems, the channels are characterized by a narrow, leveed single-thread morphology with maximum width approximately one tenth the width of the mainstem river. The channels typically have a V shaped cross-section, unlike most fluvial channels. These channels develop as lakes become isolated from the river by sedimentation. Narrowing of the connection between river and lake causes a sediment-laden jet to develop. Levees develop along the margins of the jet leading to channel emergence and eventual levee aggradation to the height of the mainstem levees. Bi-directional flow in these channels is common. Outflows from the lake scour sediment and prevent channel blockage. We propose that channel geometry and size are then controlled by a dynamic balance between channel narrowing by suspended sediment deposition and incision and widening by mass failure of banks during outflows. Tie channels are laterally stable and may convey flow for hundreds to a few thousand of years.

  14. Acolhimento: tecnologia leve nos processos gerenciais do enfermeiro Acogimiento: tecnología leve en los procesos gerenciales del enfermero Welcoming: soft technology in nurse's management processes

    Directory of Open Access Journals (Sweden)

    Flávia Raquel Rossi

    2005-06-01

    Full Text Available O estudo teve por objetivo identificar a utilização das tecnologias leves nos processos gerenciais do enfermeiro e a sua interferência na produção do cuidado. Constituiu-se em um estudo de caso de abordagem qualitativa, cujos sujeitos da pesquisa foram enfermeiros de um setor de internação de um hospital geral localizado em um município do interior do Rio Grande do Sul. Os dados foram coletados através da observação livre do trabalho do enfermeiro. Nos processos gerenciais do enfermeiro identificou-se a utilização de tecnologias leves, entre elas o acolhimento, assim como alguns fatores que o configuram, sendo possível afirmar que ao utilizar essa tecnologia o enfermeiro produz e promove a humanização do cuidado.El objetivo de este estudio fué la utilización de tecnologías leves en los procesos gerenciales del enfermería e su interferencia al producir lo cuidado. Se constituye en un estudio de caso de abordaje cualitativa e los sujetos de investigación eran enfermeros de un sector de internación de un hospital general localizado en una ciudad del Río Grande do Sul. Los datos fueron colectados a través de la libre observación de sus trabajos. En los procesos gerenciales del enfermero, se identifico el uso de tecnologías leves, entre ellas, el acogimiento, así como algunos factores que lo configuran, siendo posible afirmar que al utilizar esa tecnología, el enfermero produce e promociona la humanización del cuidado.This study aimed the identification of the use of soft technologies in nursing management processes and their interference in care production. It was constituted in a case study case of quality feature and the research subjects were nurses of a public hospital located in a city of Rio Grande do Sul. Data were collected by means of free observation of the nurses' job. In their managing processes, it was identified the use of soft technologies, among them the welcoming, as well as some factors that present it

  15. River Activism, “Levees-Only” and the Great Mississippi Flood of 1927

    Directory of Open Access Journals (Sweden)

    Ned Randolph

    2018-02-01

    Full Text Available This article investigates media coverage of 19th and early 20th century river activism and its effect on federal policy to control the Mississippi River. The U.S. Army Corps of Engineers’ “levees-only” policy—which joined disparate navigation and flood control interests—is largely blamed for the Great Flood of 1927, called the largest peacetime disaster in American history. River activists organized annual conventions, and later, professional lobbies organized media campaigns up and down the Mississippi River to sway public opinion and pressure Congress to fund flood control and river navigation projects. Annual river conventions drew thousands of delegates such as plantation owners, shippers, bankers, chambers of commerce, governors, congressmen, mayors and cabinet members with interests on the Mississippi River. Public pressure on Congress successfully captured millions of federal dollars to protect property, drain swamps for development, subsidize local levee districts and influence river policy.

  16. Drought and reservoirs: intended benefits and unintended consequences

    Science.gov (United States)

    Di Baldassarre, Giuliano; AghaKouchak, Amir; Rangecroft, Sally; Wanders, Niko; Kuil, Linda; Veldkamp, Ted; van Loon, Anne

    2017-04-01

    Socioeconomic drought can be broadly defined as a condition whereby water demand cannot be satisfied by water supply. Here we posit that while reservoirs often alleviate socioeconomic drought, they can lead to unintended consequences in the medium-long term. Losses caused by socioeconomic drought tend to trigger public pressure for action, which can result in the introduction or expansion of reservoirs to store more water during high flow conditions, and release it during low flow conditions. In the short term, increasing reservoir storage is often beneficial because frequency, magnitude, and duration of drought can be significantly reduced. Yet, it is important to note that reservoirs may fail in mitigating major, prolonged drought, because reservoir storage is unavoidably limited. In the medium-long term, two main dynamics tend to emerge, which often generate unintended consequences. The first one, termed here as "supply-demand cycle", is when increasing water supply triggers additional development and thus generates higher demand, which then offsets the benefit of reservoirs as a water supply source. This is a self-reinforcing feedback, or vicious cycle, as the occurrence of a new socioeconomic drought will then likely trigger further expansion of reservoir storage to, again, increase water supply. A second dynamic, termed here as "reservoir effect" (after White's "levee effect"), is when extended periods of abundant water supply, secured by reservoirs, generate a decline of coping capacities through increased competition for water and reduced shocks to the system, which in turn increases the vulnerability of the system to socio-economic drought. In other words, while a frequent experience of water shortages can help keep high levels of preparedness, some elements of system's resilience can be lost when minor-to-moderate events are avoided. As a result, the development of reservoirs can generate a shift from frequent socioeconomic drought conditions to rare

  17. SIRS Digues 2.0: A Cooperative Software For Levees Management

    Directory of Open Access Journals (Sweden)

    Moins Isabelle

    2016-01-01

    Full Text Available SIRS Digues is a computing tool that makes informations on levees more durable and accessible in order to enhance their management. The first version of the software, which was IRSTEA’s initiative, was deployed in 2004. The second version was released in 2015. This article aims at pointing out the innovative aspects of this last version. They concern thematic and functionalities, computing technics and architecture, and last but not least, the business model chosen in order to build a long lasting software. The software’s kernel is sketched to propose a general description of levees: it focuses on description of the levees and linked objects, on disorders that affects them, on works... Most of these topics were already broached by the first version. The kernel of the version 2 may be extended using optional thematic modules. These modules concern: vegetation monitoring, reporting (in coherence with current French regulatory requirements, riverbanks, riverbed... Main functionnalities perfomed by SIRS Digues V1 and V2 are : data structuring and centralisation, quick access to relevant data, reporting and mapping, etc. SIRS Digues 2.0 updates and improves already existing functionalities of the first version. SIRS Digues V2 relies on an documentoriented NoSQL database, CouchDB, and on geospatial libraries, Geotoolkit and Apache-SIS. SIRS Digues V2 was released with a copyleft license. Copyrights belong to the French levees managers’ society, “France Digues”, which acts as a cooperative. Members put their heads together in order to gather their financial capacities and fund software development. France Digues has got the technical and thematic expertise and supply various services to the members. This business model aims to ensure accessibility, durability and adaptability of the software.

  18. The Legacy of the 1948 Underseepage and Crevasse Maps, Lower Mississippi River Levees

    Science.gov (United States)

    2017-04-01

    for wider dissemination. This map folio identifies sand boil locations, historic crevasses, severity of seepage, and extent of seepage control ...comprehensive study by USACE (1956) into levee underseepage and its control . This map folio was limited in distribution, never officially published as a...technical memorandum/report, and was thought to have been lost. The map folio was discovered as part of ongoing research into sand boils in the LMV and

  19. Combined Wave and Surge Overtopping of Levees: Flow Hydrodynamics and Articulated Concrete Mat Stability

    Science.gov (United States)

    2008-08-01

    armoring systems must resist the forces of fast -flowing, turbulent water that has overtopped the levee crest. Figure 4 illustrates the three overtopping...2 2 2 % % % A u Ah s s h R C H H cR (1) and − =2 22 % % %A u Au ss u R C HgH cR (2) where: hA2% = peak flow depth exceeded by 2

  20. Cultural Resources Survey, Testing, and Exploratory Trenching for the Louisiana State Penitentiary Levee Enlargement Project, West Feliciana Parish, Louisiana

    National Research Council Canada - National Science Library

    2001-01-01

    2The results of a Phase I cultural resources survey and a Phase II National Register testing program within the proposed levee enlargement at Louisiana State Penitentiary, West Feliciana Parish, Louisiana are presented...

  1. A Case History of Embankment Failure: Geological and Geotechnical Aspects of the Celotex Levee Failure, New Orleans, Louisiana

    National Research Council Canada - National Science Library

    Dunbar, Joseph

    1999-01-01

    .... The data examined during research on the causes of levee failure included geologic setting, historic bank migration and previous bank lines, thalweg profiles, width/depth ratios, scour pool movement, and river profiles...

  2. The glaciogenic reservoir analogue studies project (GRASP)

    DEFF Research Database (Denmark)

    Moscariello, A.; Moreau, Julien; Vegt, P. van der

    increasing the risk associated with developing effectively these reservoirs. Therefore a analogue-based predictive stratigraphical and sedimentological model can help to steer drilling strategy and reduce uncertainties and associated risks. For this purpose the GRASP joint industry programme was established......Tunnel galleys are common features in Palaeozoic glacigenic succession in North Afrcica and Middle East and they are amongst the most challenging target for hydrocarbon exploration and developing drilling in these regions. Similarly, these buried valleys form important groundwater reservoirs...... in Quaternary glaciated areas and their nature and sediment composition is critical to drive a sustainable production strategy and assess their vulnerability. Seismic resolution however, often limits the understanding of channel valleys morphology, 3D geometry and internal reservoir distribution, thus...

  3. Uso del tratamiento acupuntural en pacientes con trastorno depresivo recurrente leve

    Directory of Open Access Journals (Sweden)

    Roberto Anselmo Ramos Valverde

    2014-08-01

    Full Text Available La efectividad probada del tratamiento acupuntural en el episodio depresivo leve posibilitó realizar un estudio continuado y experimental en el Centro Comunitario Provincial de Salud Mental de Las Tunas, con el objetivo de determinar la efectividad del empleo de la acupuntura en pacientes portadores de trastorno depresivo recurrente leve. El universo estuvo constituido por todos los pacientes diagnosticados clínicamente con la enfermedad, que acudieron a la consulta de Medicina Natural y Tradicional de esta entidad entre marzo de 2011 y marzo de 2013. La muestra quedó constituida por 60 pacientes que cumplieron los criterios diagnóstico y de inclusión establecidos para la investigación, se aplicó un muestreo aleatorio simple, que permitió conformar dos grupos: uno de estudio, al que se le aplicó tratamiento acupuntural y uno control, que recibió tratamiento con amitriptilina. Los resultados mostraron que la astenia y el insomnio fueron los síntomas asociados más frecuentes; la depresión se eliminó en un mínimo de los pacientes que recibieron tratamiento con acupuntura y los síntomas asociados persistieron notablemente en los mismos. Por lo que se concluye que el tratamiento tradicional acupuntural no es una terapia efectiva en los pacientes con trastorno depresivo recurrente leve

  4. Dedicated IT infrastructure for Smart Levee Monitoring and Flood Decision Support

    Directory of Open Access Journals (Sweden)

    Balis Bartosz

    2016-01-01

    Full Text Available Smart levees are being increasingly investigated as a flood protection technology. However, in large-scale emergency situations, a flood decision support system may need to collect and process data from hundreds of kilometers of smart levees; such a scenario requires a resilient and scalable IT infrastructure, capable of providing urgent computing services in order to perform frequent data analyses required in decision making, and deliver their results in a timely fashion. We present the ISMOP IT infrastructure for smart levee monitoring, designed to support decision making in large-scale emergency situations. Most existing approaches to urgent computing services in decision support systems dealing with natural disasters focus on delivering quality of service for individual, isolated subsystems of the IT infrastructure (such as computing, storage, or data transmission. We propose a holistic approach to dynamic system management during both urgent (emergency and normal (non-emergency operation. In this approach, we introduce a Holistic Computing Controller which calculates and deploys a globally optimal configuration for the entire IT infrastructure, based on cost-of-operation and quality-of-service (QoS requirements of individual IT subsystems, expressed in the form of Service Level Agreements (SLAs. Our approach leads to improved configuration settings and, consequently, better fulfilment of the system’s cost and QoS requirements than would have otherwise been possible had the configuration of all subsystems been managed in isolation.

  5. Geometry of the proximal part of the modern turbidite depositional system of the Carapebus Formation, Campos Basin: a model for reservoir heterogeneities; Geometria da porcao proximal do sistema deposicional turbiditico moderno da Formacao Carapebus, Bacia de Campos; modelo para heterogeneidades de reservatorio

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Luis Claudio Ribeiro; Kowsmann, Renato Oscar; Almeida Junior, Waldemar de; Murakami, Celso Yoshihito; Schreiner, Simone; Miller, Dennis James; Piauilino, Pedro Orlando Vasconcelos [PETROBRAS, Rio de Janeiro, RJ (Brazil). Exploracao e Producao. Unidade de Servico Submarino]. E-mail: machadolc@petrobras.com.br

    2004-11-01

    The deep-water marine sedimentary environment of the Cenozoic of the Campos Basin is examined at the modern sea floor, where it can be better understood. This environment is responsible for the genesis of the turbidite systems of the Carapebus Formation, the reservoirs that hold more than 90% of Brazil's petroleum reserves. The study was developed with the records of regional side-scan sonar, swath bathymetry, sub-bottom profiler data, standard multichannel 3D seismic surveys and piston cores covering almost the entire basin. After leaving the Almirante Camara Canyon, the turbiditic flows erode the muddy debris apron surrounding the continental slope and begin to deposit thick layers of clean sand into a big trough in water depths of 1800 m to 3000 m. The trough is 3.5 km wide, 150 m deep, 150 km long, and is formed by a chain of salt withdrawal mini-basins. In some places the sea floor is flat enough to develop today a depositional lobe, in all aspects analogous to the best, geologically ancient petroleum reservoirs in the basin. Aspects of the system: 1) the arcosean sands are brought by the river, cross the shelf, the incised valley, the canyon, and deposit as turbidites - they do not originate from a collapse of the continental slope; 2) a wide muddy debris apron surrounds the continental slope (slope apron), and represents a huge volume of sediment in the Campos Basin ; 3) the turbidites do not develop a submarine fan, but are deposited in an elongated trough formed by salt tectonics; 4) the turbidite beds, both in the lobe or in the trough, are not deposited during a single episode, but in multiple events over significant geologic time in which small channels which brought the turbidites avulse and meander along the entire depositional area, building a single amalgamated bed; 5) classic channel-levees are not present because this system comprises a sandy braid plain and the levees are as sandy as the channel; 6) a hierarchical depositional model for bulb

  6. Obtenção de concreto leve utilizando agregados reciclados

    Directory of Open Access Journals (Sweden)

    Paulo César Correia Gomes

    Full Text Available O concreto leve pode ser obtido pela substituição do agregado convencional por agregado de menor densidade, como a argila expandida, a qual apresenta também alta porosidade e absorção de água elevada. Essas propriedades se assemelham às dos agregados reciclados de resíduos de construção, o que os torna aptos para a obtenção de um concreto leve. Porém, os agregados reciclados diferem quanto a composição variável, menor resistência a esforços e à abrasão, e formato mais irregular. Assim, o artigo analisa como algumas propriedades dos agregados reciclados influenciam no comportamento do concreto leve nos estados fresco e endurecido. O estudo utilizou dois tipos de agregados reciclados, um oriundo de blocos vazados de concreto com EPS (ARBCE e outro de blocos cerâmicos (ARBC, com o propósito de entender a variabilidade dos materiais caracterizando as composições desses agregados e verificar a viabilidade de aplicação deles na obtenção de concretos leves. Os agregados reciclados foram britados por dois diferentes equipamentos (moinho argamassadeira para o ARBC e britador de martelo para o ARBCE. Os agregados reciclados obtidos desses processos distintos apresentaram distribuição granulométrica e forma diferentes. Com ambos os agregados reciclados foi possível produzir concretos leves, ou seja, com massa específica abaixo de 2,00 g/cm³. As resistências à compressão aos 28 dias entre 9,0 e 13,0 MPa indicam uso em elementos sem função estrutural, mas aplicáveis em componentes construtivos de resistência moderada (p.ex. painéis e blocos.

  7. Insect diversity in organic rice fields under two management systems of levees vegetation.

    Science.gov (United States)

    Acosta, L G; Jahnke, S M; Redaelli, L R; Pires, P R S

    2017-11-01

    Simplified environments characterize agroecosystems, reducing the diversity of associated plants, which are not cultivated for economic purposes, causing unbalances that can promote the emergence of cultivated plants pests, as well as the reduction of their natural enemies. Management systems that increase diversity in agroecosystems can extend the action of natural enemies of pests. Studies to understand the diversity of insects associated with rice cultivation and determine their ecological guilds can provide information about the composition and structure of such ecosystems, which can be applied to integrated pest management. Therefore, the study aimed to describe and compare groups of insects in irrigated rice fields, with organic management using two different systems of levees vegetation management, and relate them to the phenological states of rice cultivation (seedling, vegetative, and reproductive). Samples were taken in a plantation located in Águas Claras district of Viamão, RS. The total area of 18 ha was divided into two. A subarea called not cut (NC), where wild vegetation of levees was maintained, and the subarea named cut (C), where monthly cuts were made to levees vegetation, from the beginning of soil preparation until the harvest. From October 2012 to March 2013 were held weekly collections in quadrats randomly located in both the rice fields and the levees. A total of 800 insects were collected, 429 in the C subarea and 371 in the NC. There were identified 97 morphospecies in the C and 108 in NC, being 54 shared between the subareas. The captured insects were grouped into guilds: saprophages (C = 38.2%; NC = 27.5%), phytophagous (C = 28.5%; NC = 33.2%), entomophagous (grouping parasitoids and predators) (C = 29.4%; NC = 35%) and finally other insects (C = 4 %; NC = 4.3%). The peak abundance of phytophagous and entomophagous was registered in the vegetative stage of rice. At the same stage the UPGMA analysis showed that similarity in species

  8. S-wave velocity measurements along levees in New Orleans using passive surface wave methods

    Science.gov (United States)

    Hayashi, K.; Lorenzo, J. M.; Craig, M. S.; Gostic, A.

    2017-12-01

    In order to develop non-invasive methods for levee inspection, geophysical investigations were carried out at four sites along levees in the New Orleans area: 17th Street Canal, London Avenue Canal, Marrero Levee, and Industrial Canal. Three of the four sites sustained damage from Hurricane Katrina in 2005 and have since been rebuilt. The geophysical methods used include active and passive surface wave methods, and capacitively coupled resistivity. This paper summarizes the acquisition and analysis of the 1D and 2D passive surface wave data. Twelve wireless seismic data acquisition units with 2 Hz vertical component geophones were used to record data. Each unit includes a GPS receiver so that all units can be synchronized over any distance without cables. The 1D passive method used L shaped arrays of three different sizes with geophone spacing ranging from 5 to 340 m. Ten minutes to one hour of ambient noise was recorded with each array, and total data acquisition took approximately two hours at each site. The 2D method used a linear array with a geophone spacing of 5m. Four geophones were moved forward every 10 minutes along 400 1000 m length lines. Data acquisition took several hours for each line. Recorded ambient noise was processed using the spatial autocorrelation method and clear dispersion curves were obtained at all sites (Figure 1a). Minimum frequencies ranged from 0.4 to 0.7 Hz and maximum frequencies ranged from 10 to 30 Hz depending on the site. Non-linear inversion was performed and 1D and 2D S-wave velocity models were obtained. The 1D method penetrated to depths ranging from 200 to 500 m depending on the site (Figure 1b). The 2D method penetrated to a depth of 40 60 m and provided 400 1000 m cross sections along the levees (Figure 2). The interpretation focused on identifying zones beneath the levees or canal walls having low S-wave velocities corresponding to saturated, unconsolidated sands, or low-rigidity clays. Resultant S-wave velocity profiles

  9. Insect diversity in organic rice fields under two management systems of levees vegetation

    Directory of Open Access Journals (Sweden)

    L. G. Acosta

    2017-03-01

    Full Text Available Abstract Simplified environments characterize agroecosystems, reducing the diversity of associated plants, which are not cultivated for economic purposes, causing unbalances that can promote the emergence of cultivated plants pests, as well as the reduction of their natural enemies. Management systems that increase diversity in agroecosystems can extend the action of natural enemies of pests. Studies to understand the diversity of insects associated with rice cultivation and determine their ecological guilds can provide information about the composition and structure of such ecosystems, which can be applied to integrated pest management. Therefore, the study aimed to describe and compare groups of insects in irrigated rice fields, with organic management using two different systems of levees vegetation management, and relate them to the phenological states of rice cultivation (seedling, vegetative, and reproductive. Samples were taken in a plantation located in Águas Claras district of Viamão, RS. The total area of 18 ha was divided into two. A subarea called not cut (NC, where wild vegetation of levees was maintained, and the subarea named cut (C, where monthly cuts were made to levees vegetation, from the beginning of soil preparation until the harvest. From October 2012 to March 2013 were held weekly collections in quadrats randomly located in both the rice fields and the levees. A total of 800 insects were collected, 429 in the C subarea and 371 in the NC. There were identified 97 morphospecies in the C and 108 in NC, being 54 shared between the subareas. The captured insects were grouped into guilds: saprophages (C = 38.2%; NC = 27.5%, phytophagous (C = 28.5%; NC = 33.2%, entomophagous (grouping parasitoids and predators (C = 29.4%; NC = 35% and finally other insects (C = 4 %; NC = 4.3%. The peak abundance of phytophagous and entomophagous was registered in the vegetative stage of rice. At the same stage the UPGMA analysis showed that

  10. Transport of reservoir fines

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander; Stenby, Erling Halfdan

    Modeling transport of reservoir fines is of great importance for evaluating the damage of production wells and infectivity decline. The conventional methodology accounts for neither the formation heterogeneity around the wells nor the reservoir fines’ heterogeneity. We have developed an integral...

  11. SILTATION IN RESERVOIRS

    African Journals Online (AJOL)

    Calls have been made to the government through various media to assist its populace in combating this nagging problem. It was concluded that sediment maximum accumulation is experienced in reservoir during the periods of maximum flow. Keywords: reservoir model, siltation, sediment, catchment, sediment transport. 1.

  12. Dynamic reservoir well interaction

    NARCIS (Netherlands)

    Sturm, W.L.; Belfroid, S.P.C.; Wolfswinkel, O. van; Peters, M.C.A.M.; Verhelst, F.J.P.C.M.

    2004-01-01

    In order to develop smart well control systems for unstable oil wells, realistic modeling of the dynamics of the well is essential. Most dynamic well models use a semi-steady state inflow model to describe the inflow of oil and gas from the reservoir. On the other hand, reservoir models use steady

  13. Reservoir Engineering Management Program

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.H.; Schwarz, W.J.

    1977-12-14

    The Reservoir Engineering Management Program being conducted at Lawrence Berkeley Laboratory includes two major tasks: 1) the continuation of support to geothermal reservoir engineering related work, started under the NSF-RANN program and transferred to ERDA at the time of its formation; 2) the development and subsequent implementation of a broad plan for support of research in topics related to the exploitation of geothermal reservoirs. This plan is now known as the GREMP plan. Both the NSF-RANN legacies and GREMP are in direct support of the DOE/DGE mission in general and the goals of the Resource and Technology/Resource Exploitation and Assessment Branch in particular. These goals are to determine the magnitude and distribution of geothermal resources and reduce risk in their exploitation through improved understanding of generically different reservoir types. These goals are to be accomplished by: 1) the creation of a large data base about geothermal reservoirs, 2) improved tools and methods for gathering data on geothermal reservoirs, and 3) modeling of reservoirs and utilization options. The NSF legacies are more research and training oriented, and the GREMP is geared primarily to the practical development of the geothermal reservoirs. 2 tabs., 3 figs.

  14. Risk Analysis of Reservoir Operations Considering Short-Term Flood Control and Long-Term Water Supply: A Case Study for the Da-Han Creek Basin in Taiwan

    Directory of Open Access Journals (Sweden)

    Wen-Ming Cheng

    2017-06-01

    Full Text Available This study applies an integrated methodology to assess short-term over-levee risk and long-term water shortage risk in the Da-Han Creek basin, which is the most important flood control and water storage system in northern Taiwan. An optimization model for reservoir flood control and water supply is adopted, to determine reservoir releases based on synthetic inflow hydrographs during typhoons, which are generated by Monte Carlo simulations. The release is then used to calculate the water level at a downstream control point using a novel developed back-propagation neural network-based model, to reduce computational complexity and achieve automatic-efficient risk evaluation. The calculated downstream water levels and final reservoir water levels after a typhoon event are used to evaluate the mapped over-levee risk and water shortage risk, respectively. The results showed that the different upper limit settings for the reservoir have a significant influence on the variation of 1.19 × 10−5% to 75.6% of the water shortage risk. This occurs because of the insufficient inflow and narrow storage capacity of the Shih-Men Reservoir during drought periods. However, the upper limit settings have a minor influence (with a variation of only 0.149% to 0.157% on the over-levee risk in typhoon periods, because of the high protection standards for the downstream embankment.

  15. Marcadores de estrés oxidativo en hipertensión leve

    Directory of Open Access Journals (Sweden)

    Raquel Oré

    2007-12-01

    Full Text Available Introducción: La hipertensión es un factor de riesgo cardiovascular y en 90% de los casos se desconoce el mecanismo que la inicia. Recientemente, se considera que la hipertensión es un síndrome de anormalidades metabólicas y estructurales, en el que las especies reactivas derivadas del oxígeno (EROs juegan un papel fisiopatológico preponderante en su desarrollo. Objetivo: Determinar los niveles séricos de zinc, selenio y magnesio en personas normotensas e hipertensas. Asimismo, valorar la actividad de la enzima superóxido dismutasa (SOD y los niveles de sustancias reactivas al ácido tiobarbitúrico (TBARS en ambos grupos de estudio. Diseño: Estudio analítico observacional, tipo casos y controles. Lugar: Centro de Investigación de Bioquímica y Nutrición, Universidad Nacional Mayor de San Marcos. Material biológico: Sangre de pacientes normotensos y con hipertensión leve. Intervenciones: Se obtuvo las muestras de sangre de 20 pacientes normotensos y 20 con hipertensión leve, con edades entre 50 y 60 años, después de un ayuno de 12 horas, realizándose el estudio en suero y sangre total. Principales medidas de resultados: Variación de niveles de TBARS, oligoelementos (Se, Zn y Mg, medición de actividad de SOD eritrocitario. Resultados: En el grupo de hipertensos, se obtuvo incremento significativo de magnesio y TBARS y disminución significativa de zinc y de la actividad de SOD. Conclusiones: Se demuestra el compromiso del estrés oxidativo en pacientes con hipertensión leve. La hipermagnesemia podría explicarse por el daño a los elementos formes de la sangre.

  16. Reservoir characterization of Pennsylvanian sandstone reservoirs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.

    1995-02-01

    This final report summarizes the progress during the three years of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description; (ii) scale-up procedures; (iii) outcrop investigation. The first section describes the methods by which a reservoir can be described in three dimensions. The next step in reservoir description is to scale up reservoir properties for flow simulation. The second section addresses the issue of scale-up of reservoir properties once the spatial descriptions of properties are created. The last section describes the investigation of an outcrop.

  17. Seepage and Piping through Levees and Dikes using 2D and 3D Modeling Codes

    Science.gov (United States)

    2016-06-01

    Flood & Coastal Storm Damage Reduction Program ERDC/CHL TR-16-6 June 2016 Seepage and Piping through Levees and Dikes Using 2D and 3D Modeling Codes...of this Technical Report is to evaluate the benefits of three- dimensional ( 3D ) modeling of common seepage and piping issues along embankments over...traditional two-dimensional (2D) models . To facilitate the evaluation, one 3D model , two 2D cross-sectional models , and one 2D plan-view model were

  18. A Gradually Varied Approach to Model Turbidity Currents in Submarine Channels

    Science.gov (United States)

    Bolla Pittaluga, M.; Frascati, A.; Falivene, O.

    2018-01-01

    We develop a one-dimensional model to describe the dynamics of turbidity current flowing in submarine channels. We consider the flow as a steady state polydisperse suspension accounting for water detrainment from the clear water-turbid interface, for spatial variations of the channel width and for water and sediment lateral overspill from the channel levees. Moreover, we account for sediment exchange with the bed extending the model to deal with situations where the current meets a nonerodible bed. Results show that when water detrainment is accounted for, the flow thickness becomes approximately constant proceeding downstream. Similarly, in the presence of channel levees, the flow tends to adjust to channel relief through the lateral loss of water and sediment. As more mud is spilled above the levees relative to sand, the flow becomes more sand rich proceeding downstream when lateral overspill is present. Velocity and flow thickness predicted by the model are then validated by showing good agreement with laboratory observations. Finally, the model is applied to the Monterey Canyon bathymetric data matching satisfactorily the December 2002 event field measurements and predicting a runout length consistent with observations.

  19. Oficinas de estimulação cognitiva adaptadas para idosos analfabetos com transtorno cognitivo leve

    Directory of Open Access Journals (Sweden)

    Izabel Borges dos Santos

    2012-12-01

    Full Text Available Oficinas de estimulação cognitiva para idosos analfabetos com transtorno cognitivo leve é um tema pouco pesquisado. Objetivou-se verificar a autopercepção da memória em idosos analfabetos com transtorno cognitivo leve, antes e após oficinas de estimulação cognitiva, adaptadas para analfabetos. Trata-se de uma pesquisa qualitativa, realizada na Unidade de Saúde de Taguatinga-DF, envolvendo 63 idosos: 22 no Grupo Experimental (GE, com 10 oficinas; 21 no Grupo Controle 1 (GC1, com 10 palestras; e 20 no Grupo Controle 2 (GC2, sem intervenção. Foram realizadas entrevistas semiestruturadas antes e após intervenções, perguntando-se sobre memória. Aos GE e GC1 foram oferecidas atividades semanais de duas horas. A idade média foi 72,8 anos, 92% do sexo feminino. Na pré-intervenção, 82% haviam piorado memória no último ano. Na pós-intervenção, GC1 e GC2 mantiveram alterações da memória, enquanto GE melhorou cognição. Conclui-se que as oficinas e palestras proporcionaram melhora na funcionalidade e socialização/integração.

  20. Oficinas de estimulação cognitiva adaptadas para idosos analfabetos com transtorno cognitivo leve

    Directory of Open Access Journals (Sweden)

    Izabel Borges dos Santos

    Full Text Available Oficinas de estimulação cognitiva para idosos analfabetos com transtorno cognitivo leve é um tema pouco pesquisado. Objetivou-se verificar a autopercepção da memória em idosos analfabetos com transtorno cognitivo leve, antes e após oficinas de estimulação cognitiva, adaptadas para analfabetos. Trata-se de uma pesquisa qualitativa, realizada na Unidade de Saúde de Taguatinga-DF, envolvendo 63 idosos: 22 no Grupo Experimental (GE, com 10 oficinas; 21 no Grupo Controle 1 (GC1, com 10 palestras; e 20 no Grupo Controle 2 (GC2, sem intervenção. Foram realizadas entrevistas semiestruturadas antes e após intervenções, perguntando-se sobre memória. Aos GE e GC1 foram oferecidas atividades semanais de duas horas. A idade média foi 72,8 anos, 92% do sexo feminino. Na pré-intervenção, 82% haviam piorado memória no último ano. Na pós-intervenção, GC1 e GC2 mantiveram alterações da memória, enquanto GE melhorou cognição. Conclui-se que as oficinas e palestras proporcionaram melhora na funcionalidade e socialização/integração.

  1. Application of the TDR technique for the detection of changes in the internal structure of an earthen flood levee

    Science.gov (United States)

    Janik, Grzegorz; Dawid, Małgorzata; Walczak, Amadeusz; Słowińska-Osypiuk, Joanna; Skierucha, Wojciech; Wilczek, Andrzej; Daniel, Anna

    2017-03-01

    Failures of earthen flood protection structures cause enormous material loss. Despite this, in the majority these are structures that were built decades ago. As an example, in Poland, the time of operation of approximately three quarters of existing levees and embankments is over 40 years. A similar situation exists in many other European countries. In the period 1998-2009 the economic losses caused by floods amounted to over 60 thousand million Euro. This accounts for approximately one third of the total losses caused by environmental factors. Ruptures of embankments or levees occur as a result of long-lasting elevated water levels in rivers, and such events are always preceded by changes in their internal structure. Such changes cannot be detected from the outside. This paper presents a new method, never used before, for the determination of changes in the internal structure of the body of a levee. The dynamics of the displacements is described by means of new mathematical formulae. The input data necessary for their application include the dynamics of changes in the value of volumetric moisture that is measured with a freely selected short time step by means of the time-domain-reflectrometry technique. The formulae were created on the basis of hitherto unnoticed and uninterpreted drops in moisture a moment before and a moment after the saturation of inner spaces of the levee body. The results obtained from calculations were compared with data from measurements on a physical model of a levee. The settlement values calculated using the method proposed are convergent with those of the true settlement. The maximum relative error was as low as 19%. The method proposed permits the location of changes in the internal structure of a levee before its rupture. Its application is the main component of a system of early warning against floods.

  2. Capacitively coupled resistivity survey of the levee surrounding the Omaha Public Power District Nebraska City Power Plant, June 2011

    Science.gov (United States)

    Burton, Bethany L.; Cannia, James C.

    2011-01-01

    This report is a release of digital data from a capacitively coupled resistivity survey conducted on June 13, 2011, on the flood-protection levees surrounding the Omaha Public Power District Nebraska City power plant. The U.S. Geological Survey Crustal Geophysics and Geochemistry Science Center and the Nebraska Water Science Center performed the survey in response to a flood on the Missouri River. A single line of resistivity profiling was completed along the center line of the section of levee 573 that surrounds the power plant.

  3. Characterization of dynamic change of Fan-delta reservoir properties in water-drive development

    Energy Technology Data Exchange (ETDEWEB)

    Wu Shenghe; Xiong Qihua; Liu Yuhong [Univ. of Petroleum Changping, Beijing (China)

    1997-08-01

    Fan-delta reservoir in Huzhuangji oil field of east China, is a typical highly heterogeneous reservoir. The oil field has been developed by water-drive for 10 years, but the oil recovery is less than 12%, and water cut is over 90%, resulting from high heterogeneity and serious dynamic change of reservoir properties. This paper aims at the study of dynamic change of reservoir properties in water-drive development. Through quantitative imaging analysis and mercury injection analysis of cores from inspection wells, the dynamic change of reservoir pore structure in water-drive development was studied. The results show that the {open_quotes}large pore channels{close_quotes} develop in distributary channel sandstone and become larger in water-drive development, resulting in more serious pore heterogeneity. Through reservoir sensitivity experiments, the rock-fluid reaction in water-drive development is studied. The results show the permeability of some distal bar sandstone and deserted channel sandstone becomes lower due to swelling of I/S clay minerals in pore throats. OD the other hand, the permeability of distributary channel and mouth bar sandstone become larger because the authigenic Koalinites in pore throats are flushed away with the increase of flow rate of injection water. Well-logging analysis of flooded reservoirs are used to study the dynamic change of reservoir properties in various flow units. The distribution of remaining oil is closely related to the types and distribution of flow units.

  4. The Impact of Corps Flood Control Reservoirs in the June 2008 Upper Mississippi Flood

    Science.gov (United States)

    Charley, W. J.; Stiman, J. A.

    2008-12-01

    The US Army Corps of Engineers is responsible for a multitude of flood control project on the Mississippi River and its tributaries, including levees that protect land from flooding, and dams to help regulate river flows. The first six months of 2008 were the wettest on record in the upper Mississippi Basin. During the first 2 weeks of June, rainfall over the Midwest ranged from 6 to as much as 16 inches, overwhelming the flood protection system, causing massive flooding and damage. Most severely impacted were the States of Iowa, Illinois, Indiana, Missouri, and Wisconsin. In Iowa, flooding occurred on almost every river in the state. On the Iowa River, record flooding occurred from Marshalltown, Iowa, downstream to its confluence with the Mississippi River. At several locations, flooding exceeded the 500-year event. The flooding affected agriculture, transportation, and infrastructure, including homes, businesses, levees, and other water-control structures. It has been estimated that there was at least 7 billion dollars in damages. While the flooding in Iowa was extraordinary, Corps of Engineers flood control reservoirs helped limit damage and prevent loss of life, even though some reservoirs were filled beyond their design capacity. Coralville Reservoir on the Iowa River, for example, filled to 135% of its design flood storage capacity, with stage a record five feet over the crest of the spillway. In spite of this, the maximum reservoir release was limited to 39,500 cfs, while a peak inflow of 57,000 cfs was observed. CWMS, the Corps Water Management System, is used to help regulate Corps reservoirs, as well as track and evaluate flooding and flooding potential. CWMS is a comprehensive data acquisition and hydrologic modeling system for short-term decision support of water control operations in real time. It encompasses data collection, validation and transformation, data storage, visualization, real time model simulation for decision-making support, and data

  5. Optimising reservoir operation

    DEFF Research Database (Denmark)

    Ngo, Long le

    Anvendelse af optimeringsteknik til drift af reservoirer er blevet et væsentligt element i vandressource-planlægning og -forvaltning. Traditionelt har reservoirer været styret af heuristiske procedurer for udtag af vand, suppleret i en vis udstrækning af subjektive beslutninger. Udnyttelse af...... reservoirer involverer en lang række interessenter med meget forskellige formål (f.eks. kunstig vanding, vandkraft, vandforsyning mv.), og optimeringsteknik kan langt bedre lede frem til afbalancerede løsninger af de ofte modstridende interesser. Afhandlingen foreslår en række tiltag, hvormed traditionelle...... driftsstrategier kan erstattes af optimale strategier baseret på den nyeste udvikling indenfor computer-baserede beregninger. Hovedbidraget i afhandlingen er udviklingen af et beregningssystem, hvori en simuleringsmodel er koblet til en model for optimering af nogle udvalgte beslutningsvariable, der i særlig grad...

  6. Temporal and spatial fluctuations of heavy metals in Opa Reservoir ...

    African Journals Online (AJOL)

    The Opa Reservoir, established for water supply to the Obafemi Awolowo University community, over the years has received direct linkage to township drains as a result of the widening and dredging of its river channels. The current study aimed at documenting monthly heavy metal loads at its riverine, transition and ...

  7. Geothermal reservoir engineering

    CERN Document Server

    Grant, Malcolm Alister

    2011-01-01

    As nations alike struggle to diversify and secure their power portfolios, geothermal energy, the essentially limitless heat emanating from the earth itself, is being harnessed at an unprecedented rate.  For the last 25 years, engineers around the world tasked with taming this raw power have used Geothermal Reservoir Engineering as both a training manual and a professional reference.  This long-awaited second edition of Geothermal Reservoir Engineering is a practical guide to the issues and tasks geothermal engineers encounter in the course of their daily jobs. The bo

  8. Session: Reservoir Technology

    Energy Technology Data Exchange (ETDEWEB)

    Renner, Joel L.; Bodvarsson, Gudmundur S.; Wannamaker, Philip E.; Horne, Roland N.; Shook, G. Michael

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five papers: ''Reservoir Technology'' by Joel L. Renner; ''LBL Research on the Geysers: Conceptual Models, Simulation and Monitoring Studies'' by Gudmundur S. Bodvarsson; ''Geothermal Geophysical Research in Electrical Methods at UURI'' by Philip E. Wannamaker; ''Optimizing Reinjection Strategy at Palinpinon, Philippines Based on Chloride Data'' by Roland N. Horne; ''TETRAD Reservoir Simulation'' by G. Michael Shook

  9. unconventional natural gas reservoirs

    International Nuclear Information System (INIS)

    Correa G, Tomas F; Osorio, Nelson; Restrepo R, Dora P

    2009-01-01

    This work is an exploration about different unconventional gas reservoirs worldwide: coal bed methane, tight gas, shale gas and gas hydrate? describing aspects such as definition, reserves, production methods, environmental issues and economics. The overview also mentioned preliminary studies about these sources in Colombia.

  10. Parallel reservoir simulator computations

    International Nuclear Information System (INIS)

    Hemanth-Kumar, K.; Young, L.C.

    1995-01-01

    The adaptation of a reservoir simulator for parallel computations is described. The simulator was originally designed for vector processors. It performs approximately 99% of its calculations in vector/parallel mode and relative to scalar calculations it achieves speedups of 65 and 81 for black oil and EOS simulations, respectively on the CRAY C-90

  11. Actividades para fortalecer la formación de valores en escolares con retraso mental leve

    Directory of Open Access Journals (Sweden)

    Hermenegildo Aranda Romero

    2017-11-01

    Full Text Available Se presentan actividades encaminadas a fortalecer la formación de valores que deben tener los escolares con retraso mental leve Para la realización de este trabajo se tuvieron en cuenta métodos empíricos y teóricos, los principios pedagógicos por los cuales se rige el sistema educacional, así como las ideas de hombres Carlos Marx, José Martí, Fidel Castro Ruz, Luria, Leontiev, Vigotski y otros. Los cuales han permitido ofrecer la búsqueda de procedimientos metodológicos ordenados, con actividades concretas para fortalecer la formación de valores.

  12. Improvements in the Weeding of Levee Slope of Terraced Paddy Fields with Statutory Regulation of Places of Scenic Beauty

    Science.gov (United States)

    Uchikawa, Yoshiyuki; Kimura, Kazuhiro; Hirata, Ayumi

    A growing number of terraced paddy fields in Japan are being conserved as cultural assets like places of scenic beauty. This has meant that the task of weeding levee slope of these terraced paddy fields has become increasingly important, not only for general maintenance of the terraced paddy fields, but also because of the impact landscape, vegetation and the surrounding environment. However, the steep gradient of the levee slope and lack of footholds mean that the workability and safety associated with this weeding work is problematic. In addition, in the event that an area has been designated as a cultural asset, there are restrictions regarding how it can be modified and local farmers are reluctant to change their traditional farming methods in such cases. This study therefore sought to clarify the actual condition of the levee slope weeding work undertaken in the places of scenic beauty Obasute Tanada district. Empirical validations of potential measures for reforming the work environment were evaluated based on the findings of this investigation. We demonstrated that it is possible to modify current work practices while still maintaining and preserving the terraced paddy fields, even in designated scenic locations. To improve the working environment for levee slope weeding, we propose creating berms to serve as footholds at the toes of slopes.

  13. Efetividade de uma intervenção fisioterapêutica cognitivo-motora em idosos institucionalizados com comprometimento cognitivo leve e demência leve

    Directory of Open Access Journals (Sweden)

    Alessandra Vieira Menezes

    Full Text Available Resumo O objetivo desta pesquisa foi verificar a efetividade de quatro meses de intervenção fisioterapêutica cognitivo-motora, com frequência semanal única, na cognição, mobilidade e independência funcional de idosos com comprometimento cognitivo e demência leves residentes em instituição. Sob um ensaio clínico controlado, 15 sujeitos foram alocados entre grupo experimental (GE e controle (GC. Para avaliação dos sujeitos foram aplicados os instrumentos: Mini-Exame do Estado Mental, Teste de Fluência Verbal e Bateria de Avaliação Frontal para análise das funções cognitivas; Escala de Equilíbrio Funcional de Berg e Teste Timed Up and Go para verificação da mobilidade, e Escala de Barthel e Índice de Pfeffer para mensuração da independência funcional. O procedimento estatístico envolveu a aplicação do teste t de Student, sob significância de 5%. Quanto aos resultados, o GE apresentou melhor desempenho apenas nos testes relacionados à mobilidade ao final da intervenção (p < 0,05. A intervenção proposta apresentou eficácia sobre a mobilidade, mas não na cognição e independência funcional. O curto período de tempo e a baixa frequência semanal podem estar relacionados aos resultados obtidos.

  14. Bathymetry and capacity of Shawnee Reservoir, Oklahoma, 2016

    Science.gov (United States)

    Ashworth, Chad E.; Smith, S. Jerrod; Smith, Kevin A.

    2017-02-13

    Shawnee Reservoir (locally known as Shawnee Twin Lakes) is a man-made reservoir on South Deer Creek with a drainage area of 32.7 square miles in Pottawatomie County, Oklahoma. The reservoir consists of two lakes connected by an equilibrium channel. The southern lake (Shawnee City Lake Number 1) was impounded in 1935, and the northern lake (Shawnee City Lake Number 2) was impounded in 1960. Shawnee Reservoir serves as a municipal water supply, and water is transferred about 9 miles by gravity to a water treatment plant in Shawnee, Oklahoma. Secondary uses of the reservoir are for recreation, fish and wildlife habitat, and flood control. Shawnee Reservoir has a normal-pool elevation of 1,069.0 feet (ft) above North American Vertical Datum of 1988 (NAVD 88). The auxiliary spillway, which defines the flood-pool elevation, is at an elevation of 1,075.0 ft.The U.S. Geological Survey (USGS), in cooperation with the City of Shawnee, has operated a real-time stage (water-surface elevation) gage (USGS station 07241600) at Shawnee Reservoir since 2006. For the period of record ending in 2016, this gage recorded a maximum stage of 1,078.1 ft on May 24, 2015, and a minimum stage of 1,059.1 ft on April 10–11, 2007. This gage did not report reservoir storage prior to this report (2016) because a sufficiently detailed and thoroughly documented bathymetric (reservoir-bottom elevation) survey and corresponding stage-storage relation had not been published. A 2011 bathymetric survey with contours delineated at 5-foot intervals was published in Oklahoma Water Resources Board (2016), but that publication did not include a stage-storage relation table. The USGS, in cooperation with the City of Shawnee, performed a bathymetric survey of Shawnee Reservoir in 2016 and released the bathymetric-survey data in 2017. The purposes of the bathymetric survey were to (1) develop a detailed bathymetric map of the reservoir and (2) determine the relations between stage and reservoir storage

  15. Sedimentary processes of the lower Monterey Fan channel and channel-mouth lobe

    Science.gov (United States)

    Klaucke, I.; Masson, D.G.; Kenyon, Neil H.; Gardner, J.V.

    2004-01-01

    The distribution of deposits, sediment transport pathways and processes on the lower Monterey Fan channel and channel-mouth lobe (CML) are studied through the integration of GLORIA and TOBI sidescan sonar data with 7-kHz subbottom profiler records and sediment cores for ground-truthing. The lower Monterey channel is characterised by an up to 30-m-deep channel with poorly developed levees and alternating muddy and silty muddy overbank deposits. The channel is discontinuous, disappearing where gradients are less than about 1:350. Ground-truthing of the large CML shows that the entire CML is characterised by widespread deposits of generally fine sand, with coarser sand at the base of turbidites. Sand is particularly concentrated in finger-like areas of low-backscatter intensity and is interpreted as the result of non-turbulent sediment-gravity flows depositing metres thick massive, fine sand. TOBI sidescan sonar data reveal recent erosional features in the form of scours, secondary channels, large flow slides, and trains of blocks at the distal end of the CML. Erosion is probably related to increasing gradient as the CML approaches Murray Fracture zone and to differential loading of sandy submarine fan deposits onto pelagic clays. Reworking of older flow slides by sediment transport processes on the lobe produces trains of blocks that are several metres in diameter and aligned parallel to the flow direction. ?? 2004 Elsevier B.V. All rights reserved.

  16. Ion channeling

    International Nuclear Information System (INIS)

    Erramli, H.; Blondiaux, G.

    1994-01-01

    Channeling phenomenon was predicted, many years ago, by stark. The first channeling experiments were performed in 1963 by Davies and his coworkers. Parallely Robinson and Oen have investigated this process by simulating trajectories of ions in monocrystals. This technique has been combined with many methods like Rutherford Backscattering Spectrometry (R.B.S.), Particles Induced X-rays Emission (P.I.X.E) and online Nuclear Reaction (N.R.A.) to localize trace elements in the crystal or to determine crystalline quality. To use channeling for material characterization we need data about the stopping power of the incident particle in the channeled direction. The ratios of channeled to random stopping powers of silicon for irradiation in the direction have been investigated and compared to the available theoretical results. We describe few applications of ion channeling in the field of materials characterization. Special attention is given to ion channeling combined with Charged Particle Activation Analysis (C.P.A.A.) for studying the behaviour of oxygen atoms in Czochralski silicon lattices under the influence of internal gettering and in different gaseous atmospheres. Association between ion channeling and C.P.A.A was also utilised for studying the influence of the growing conditions on concentration and position of carbon atoms at trace levels in the MOVPE Ga sub (1-x) Al sub x lattice. 6 figs., 1 tab., 32 refs. (author)

  17. Evaporative Lithography in Open Microfluidic Channel Networks

    KAUST Repository

    Lone, Saifullah

    2017-02-24

    We demonstrate a direct capillary-driven method based on wetting and evaporation of various suspensions to fabricate regular two-dimensional wires in an open microfluidic channel through continuous deposition of micro- or nanoparticles under evaporative lithography, akin to the coffee-ring effect. The suspension is gently placed in a loading reservoir connected to the main open microchannel groove on a PDMS substrate. Hydrophilic conditions ensure rapid spreading of the suspension from the loading reservoir to fill the entire channel length. Evaporation during the spreading and after the channel is full increases the particle concentration toward the end of the channel. This evaporation-induced convective transport brings particles from the loading reservoir toward the channel end where this flow deposits a continuous multilayered particle structure. The particle deposition front propagates backward over the entire channel length. The final dry deposit of the particles is thereby much thicker than the initial volume fraction of the suspension. The deposition depth is characterized using a 3D imaging profiler, whereas the deposition topography is revealed using a scanning electron microscope. The patterning technology described here is robust and passive and hence operates without an external field. This work may well become a launching pad to construct low-cost and large-scale thin optoelectronic films with variable thicknesses and interspacing distances.

  18. Work reservoirs in thermodynamics

    Science.gov (United States)

    Anacleto, Joaquim

    2010-05-01

    We stress the usefulness of the work reservoir in the formalism of thermodynamics, in particular in the context of the first law. To elucidate its usefulness, the formalism is then applied to the Joule expansion and other peculiar and instructive experimental situations, clarifying the concepts of configuration and dissipative work. The ideas and discussions presented in this study are primarily intended for undergraduate students, but they might also be useful to graduate students, researchers and teachers.

  19. A baixa estatura leve está associada ao aumento da pressão arterial em adolescentes com sobrepeso

    Directory of Open Access Journals (Sweden)

    Ana Paula Grotti Clemente

    2012-01-01

    Full Text Available FUNDAMENTO: Estudos têm demonstrado que a desnutrição pré/pós-natal leva a um maior risco de doenças não transmissíveis, como diabetes, hipertensão e obesidade na idade adulta. OBJETIVO: Determinar se os adolescentes com sobrepeso e desnutrição leve [escores-Z altura/idade (HAZ na faixa de -2] têm pressão arterial mais elevada do que os indivíduos com sobrepeso e com estatura normal (HAZ > -1. MÉTODOS: Os participantes foram classificados como de baixa estatura leve ou de estatura normal, e estratificados de acordo com os percentis de massa corporal para a idade, como sobrepeso, peso normal ou abaixo do peso. As pressões arteriais sistólica (PAS e diastólica (PAD foram determinadas de acordo com as diretrizes e a gordura abdominal foi analisada por absorciometria de dupla emissão de raios-X. RESULTADOS: Indivíduos com baixa estatura leve e sobrepeso apresentaram valores mais elevados da PAD (p = 0,001 do que suas contrapartes de baixo peso (69,75 ± 12,03 e 54,46 ± 11,24 mmHg, respectivamente, mas semelhantes àqueles com IMC normal. Não foram encontradas diferenças nos valores de PAD em indivíduos normais, indivíduos com sobrepeso e com baixo peso entre os grupos de estatura normal. Foi encontrado um aumento na PAS (p = 0,01 entre os indivíduos com baixa estatura leve quando comparados os indivíduos com sobrepreso com suas contrapartes de baixo peso e IMC normal (114,70 ± 15,46, 97,38 ± 10,87 e 104,72 ± 12,24 mmHg, respectivamente. Embora não tenham sido observadas diferenças nas médias de PAS entre os grupos de baixa estatura leve e estatura normal, foi encontrado um intercepto significativo (p = 0,01, revelando maior PAS entre os indivíduos com baixa estatura leve. Houve correlação entre PAS e gordura abdominal (r = 0,42, ρ = 0,02 no grupo com baixa estatura leve. CONCLUSÃO: Indivíduos de baixa estatura leve com sobrepeso apresentaram maior PAS do que os de estatura normal e sobrepeso. Esses achados

  20. Advantageous Reservoir Characterization Technology in Extra Low Permeability Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Yutian Luo

    2017-01-01

    Full Text Available This paper took extra low permeability reservoirs in Dagang Liujianfang Oilfield as an example and analyzed different types of microscopic pore structures by SEM, casting thin sections fluorescence microscope, and so on. With adoption of rate-controlled mercury penetration, NMR, and some other advanced techniques, based on evaluation parameters, namely, throat radius, volume percentage of mobile fluid, start-up pressure gradient, and clay content, the classification and assessment method of extra low permeability reservoirs was improved and the parameter boundaries of the advantageous reservoirs were established. The physical properties of reservoirs with different depth are different. Clay mineral variation range is 7.0%, and throat radius variation range is 1.81 μm, and start pressure gradient range is 0.23 MPa/m, and movable fluid percentage change range is 17.4%. The class IV reservoirs account for 9.56%, class II reservoirs account for 12.16%, and class III reservoirs account for 78.29%. According to the comparison of different development methods, class II reservoir is most suitable for waterflooding development, and class IV reservoir is most suitable for gas injection development. Taking into account the gas injection in the upper section of the reservoir, the next section of water injection development will achieve the best results.

  1. Mount St. Helens Project. Cowlitz River Levee Systems, 2009 Level of Flood Protection Update Summary

    Science.gov (United States)

    2010-02-04

    bedform in a sand bed channel, where ripples , dunes , washed out dunes , and antidunes are possible. It is not, however, appropriate to describe a...bed channel, where ripples , dunes , washed out dunes , and antidunes are possible. It is not, however, appropriate to describe a gravel bed channel in...ar am et er , T Ripples Dunes Transition Upper Regime Lower Regime Figure C. 11. Regime Determination for the Cowlitz River below Castle Rock, WA

  2. Three-dimensional imaging, change detection, and stability assessment during the centerline trench levee seepage experiment using terrestrial light detection and ranging technology, Twitchell Island, California, 2012

    Science.gov (United States)

    Bawden, Gerald W.; Howle, James; Bond, Sandra; Shriro, Michelle; Buck, Peter

    2014-01-01

    A full scale field seepage test was conducted on a north-south trending levee segment of a now bypassed old meander belt on Twitchell Island, California, to understand the effects of live and decaying root systems on levee seepage and slope stability. The field test in May 2012 was centered on a north-south trench with two segments: a shorter control segment and a longer seepage test segment. The complete length of the trench area measured 40.4 meters (m) near the levee centerline with mature trees located on the waterside and landside of the levee flanks. The levee was instrumented with piezometers and tensiometers to measure positive and negative porewater pressures across the levee after the trench was flooded with water and held at a constant hydraulic head during the seepage test—the results from this component of the experiment are not discussed in this report. We collected more than one billion three-dimensional light detection and ranging (lidar) data points before, during, and after the centerline seepage test to assess centimeter-scale stability of the two trees and the levee crown. During the seepage test, the waterside tree toppled (rotated 20.7 degrees) into the water. The landside tree rotated away from the levee by 5 centimeters (cm) at a height of 2 m on the tree. The paved surface of the levee crown had three regions that showed subsidence on the waterside of the trench—discussed as the northern, central, and southern features. The northern feature is an elongate region that subsided 2.1 cm over an area with an average width of 1.35 m that extends 15.8 m parallel to the trench from the northern end of the trench to just north of the trench midpoint, and is associated with a crack 1 cm in height that formed during the seepage test on the trench wall. The central subsidence feature is a semicircular region on the waterside of the trench that subsided by as much as 6.2 cm over an area 3.4 m wide and 11.2 m long. The southern feature is an elongate

  3. Geothermal reservoir management

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, C.R.; Golabi, K.

    1978-02-01

    The optimal management of a hot water geothermal reservoir was considered. The physical system investigated includes a three-dimensional aquifer from which hot water is pumped and circulated through a heat exchanger. Heat removed from the geothermal fluid is transferred to a building complex or other facility for space heating. After passing through the heat exchanger, the (now cooled) geothermal fluid is reinjected into the aquifer. This cools the reservoir at a rate predicted by an expression relating pumping rate, time, and production hole temperature. The economic model proposed in the study maximizes discounted value of energy transferred across the heat exchanger minus the discounted cost of wells, equipment, and pumping energy. The real value of energy is assumed to increase at r percent per year. A major decision variable is the production or pumping rate (which is constant over the project life). Other decision variables in this optimization are production timing, reinjection temperature, and the economic life of the reservoir at the selected pumping rate. Results show that waiting time to production and production life increases as r increases and decreases as the discount rate increases. Production rate decreases as r increases and increases as the discount rate increases. The optimal injection temperature is very close to the temperature of the steam produced on the other side of the heat exchanger, and is virtually independent of r and the discount rate. Sensitivity of the decision variables to geohydrological parameters was also investigated. Initial aquifer temperature and permeability have a major influence on these variables, although aquifer porosity is of less importance. A penalty was considered for production delay after the lease is granted.

  4. A qualidade de vida de pessoas com deficiência mental leve

    Directory of Open Access Journals (Sweden)

    Fernanda Saviani-Zeoti

    Full Text Available Não é prática comum dar voz a pessoas com deficiência, mesmo quando se trata da investigação de sua própria qualidade de vida. Assim, este estudo teve por objetivo conhecer a opinião de 15 adultos com deficiência mental leve em relação a sua qualidade de vida e a opinião de seus cuidadores também a esse respeito, por meio de um instrumento que avalia a qualidade de vida (WHOQOL-Bref. Os dados foram analisados estatisticamente e comparados. Os resultados mostram que a diferença entre as avaliações foi pequena nas questões referentes à satisfação com os domínios físico, psicológico, das relações sociais e do meio ambiente. A avaliação feita pelas pessoas com deficiência foi apenas ligeiramente superior àquela feita por seus cuidadores. Não houve diferença estatisticamente significativa entre as avaliações, do que se conclui que as pessoas com deficiência mental são capazes de falar de suas próprias vidas de maneira positiva e bastante realista.

  5. The Eroticism of Artificial Flesh in Villiers de L'Isle Adam's L'Eve Future

    Directory of Open Access Journals (Sweden)

    Patricia Pulham

    2008-10-01

    Full Text Available Villiers de L'Isle Adam's 'L'Eve Future' published in 1886 features a fictional version of the inventor Thomas Edison who constructs a complex, custom-made android for Englishman Lord Ewald as a substitute for his unsatisfactory lover. Hadaly, the android, has a number of literary and cultural precursors and successors. Her most commonly accepted ancestor is Olympia in E. T. A. Hoffmann's 'The Sandman' (1816 and among her fascinating descendants are Oskar Kokoschka's 'Silent Woman'; Model Borghild, a sex doll designed by German technicians during World War II;‘Caracas' in Tommaso Landolfi's short story ‘Gogol's Wife' (1954; a variety of gynoids and golems from the realms of science fiction, including Ira Levin's 'Stepford Wives' (1972; and, most recently, that silicon masterpiece - the Real Doll. All, arguably, have their genesis in the classical myth of Pygmalion. This essay considers the tension between animation and stasis in relation to this myth, and explores the necrophiliac aesthetic implicit in Villiers's novel.

  6. Advances in photonic reservoir computing

    Science.gov (United States)

    Van der Sande, Guy; Brunner, Daniel; Soriano, Miguel C.

    2017-05-01

    We review a novel paradigm that has emerged in analogue neuromorphic optical computing. The goal is to implement a reservoir computer in optics, where information is encoded in the intensity and phase of the optical field. Reservoir computing is a bio-inspired approach especially suited for processing time-dependent information. The reservoir's complex and high-dimensional transient response to the input signal is capable of universal computation. The reservoir does not need to be trained, which makes it very well suited for optics. As such, much of the promise of photonic reservoirs lies in their minimal hardware requirements, a tremendous advantage over other hardware-intensive neural network models. We review the two main approaches to optical reservoir computing: networks implemented with multiple discrete optical nodes and the continuous system of a single nonlinear device coupled to delayed feedback.

  7. Encapsulated microsensors for reservoir interrogation

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  8. A Study of Sedimentation at the River Estuary on the Change of Reservoir Storage

    Directory of Open Access Journals (Sweden)

    Iskahar

    2018-01-01

    Full Text Available Estuary of the river that leads to the reservoir has characteristics include: relatively flat, there is a change in the increase of wet cross-sectional area and backwater. The backwater will cause the flow velocity to be reduced, so that the grains of sediment with a certain diameter carried by the flow will settle in the estuary of the river. The purpose of this research is to know the distribution and sedimentation pattern at the river estuary that leads to the reservoir with the change of water level in the reservoir storage, so the solution can be found to remove / reduce sediment before entering the reservoir. The method used is the experimental, by making the physical model of the river estuary leading to the reservoir. This study expects a solution to reduce sedimentation, so that sedimentation can be removed / minimized before entering the reservoir. This research tries to apply bypass channel to reduce the sedimentation at the river estuary. Bypass channels can be applied to overcome sedimentation at the river estuary, but in order for the sediment to be removed optimally, it is necessary to modify the mouth of bypass channel and channel angle.

  9. A Study of Sedimentation at the River Estuary on the Change of Reservoir Storage

    Science.gov (United States)

    Iskahar; Suripin; Isdiyana

    2018-02-01

    Estuary of the river that leads to the reservoir has characteristics include: relatively flat, there is a change in the increase of wet cross-sectional area and backwater. The backwater will cause the flow velocity to be reduced, so that the grains of sediment with a certain diameter carried by the flow will settle in the estuary of the river. The purpose of this research is to know the distribution and sedimentation pattern at the river estuary that leads to the reservoir with the change of water level in the reservoir storage, so the solution can be found to remove / reduce sediment before entering the reservoir. The method used is the experimental, by making the physical model of the river estuary leading to the reservoir. This study expects a solution to reduce sedimentation, so that sedimentation can be removed / minimized before entering the reservoir. This research tries to apply bypass channel to reduce the sedimentation at the river estuary. Bypass channels can be applied to overcome sedimentation at the river estuary, but in order for the sediment to be removed optimally, it is necessary to modify the mouth of bypass channel and channel angle.

  10. Efeito do metacaulim nas propriedades do concreto leve estrutural = Effect of metacaulim on the properties of structural lightweight concrete

    Directory of Open Access Journals (Sweden)

    João Adriano Rossignolo

    2007-01-01

    Full Text Available Este trabalho apresenta os resultados da avaliação das modificações promovidas pelo Metacaulim no desempenho das propriedades do concreto com agregados leves. Foi analisado o efeito do Metacaulim na resistência à compressão, na resistência à tração por compressão diametral, no módulo de deformação, na absorção de água por imersão e na carbonatação do concreto com agregados leves. Nos resultados obtidos verificou-se que a adição de Metacaulim melhorou significativamente o desempenho da resistência à compressão, da resistência à tração por compressão diametral e da absorção de água por imersão e da carbonatação dos concretos leves.This paper deals with properties of lightweight aggregate concrete (LWAC with Metacaulim, made with Brazilian lightweight aggregate (LWA. Compressive strength, splitting tensile strength, modulus of elasticity and water absorption were tested. The inclusion of Metacaulim in the LWAC decreased water absorption and increasedcompressive strength and splitting tensile.

  11. Williston Reservoir: Site preparation and post-flood cleanup

    International Nuclear Information System (INIS)

    Loose, J.A.

    1990-01-01

    Williston Reservoir is the second largest in Canada and ranks ninth on the world scale. It was formed by the construction of the W.A.C. Bennet Dam and is the most important hydroelectric storage reservoir and largest body of fresh water in British Columbia. Site preparation for the reservoir began in 1962, with pre-flood clearing involving salvage of merchantable timber, handfalling, machine downing, burning of slash and burial. Post-flood cleanup included timber salvage, bailing and burning debris, tractor piling and burning, crane piling in shallows, underwater cutting, and hand cutting during low drawdown. Various types of floating debris have presented problems for recreational use, log booming and transport, waterways and aviation. Protection of the spillway is accomplished with a floating boom upstream of the channel. Administration, funding, forest clearance, salvage methods, clearing standards, wood volumes, project costs, environmental concerns, and future priorities are discussed. 5 figs., 2 tabs

  12. MARKETING CHANNELS

    Directory of Open Access Journals (Sweden)

    Ljiljana Stošić Mihajlović

    2014-07-01

    Full Text Available Marketing channel is a set of entities and institutions, completion of distribution and marketing activities, attend the efficient and effective networking of producers and consumers. Marketing channels include the total flows of goods, money and information taking place between the institutions in the system of marketing, establishing a connection between them. The functions of the exchange, the physical supply and service activities, inherent in the system of marketing and trade. They represent paths which products and services are moving after the production, which will ultimately end up buying and eating by the user.

  13. Reservoir Simulations of Low-Temperature Geothermal Reservoirs

    Science.gov (United States)

    Bedre, Madhur Ganesh

    The eastern United States generally has lower temperature gradients than the western United States. However, West Virginia, in particular, has higher temperature gradients compared to other eastern states. A recent study at Southern Methodist University by Blackwell et al. has shown the presence of a hot spot in the eastern part of West Virginia with temperatures reaching 150°C at a depth of between 4.5 and 5 km. This thesis work examines similar reservoirs at a depth of around 5 km resembling the geology of West Virginia, USA. The temperature gradients used are in accordance with the SMU study. In order to assess the effects of geothermal reservoir conditions on the lifetime of a low-temperature geothermal system, a sensitivity analysis study was performed on following seven natural and human-controlled parameters within a geothermal reservoir: reservoir temperature, injection fluid temperature, injection flow rate, porosity, rock thermal conductivity, water loss (%) and well spacing. This sensitivity analysis is completed by using ‘One factor at a time method (OFAT)’ and ‘Plackett-Burman design’ methods. The data used for this study was obtained by carrying out the reservoir simulations using TOUGH2 simulator. The second part of this work is to create a database of thermal potential and time-dependant reservoir conditions for low-temperature geothermal reservoirs by studying a number of possible scenarios. Variations in the parameters identified in sensitivity analysis study are used to expand the scope of database. Main results include the thermal potential of reservoir, pressure and temperature profile of the reservoir over its operational life (30 years for this study), the plant capacity and required pumping power. The results of this database will help the supply curves calculations for low-temperature geothermal reservoirs in the United States, which is the long term goal of the work being done by the geothermal research group under Dr. Anderson at

  14. Reactive Tracers for Characterizing Fractured Geothermal Reservoirs

    Science.gov (United States)

    Hawkins, Adam J.

    Multi-component tracer tests were conducted at a 10 x 10 m well field located in the Altona Flat Rocks of northern New York. Temperature advancement between two wells separated by 14 m was monitored throughout the well field during progressive heating of the reservoir over 6 d. Multiple approaches to predicting heat transport were applied to field data and compared to temperature rise recorded during reservoir heat-up. Tracer analysis incorporated both an analytical one-dimensional model and a two-dimensional numerical model for non-uniform fractures experiencing "flow-channeling." Modeling efforts demonstrated that estimating heat transfer surface area using a combined inert/adsorbing tracer (cesium-iodide) could provide accurate forecasting of premature thermal breakthrough. In addition, thermally degrading tracer tests were used to monitor inter-well temperature during progressive reservoir heating. Inert tracers alone were, in general, inadequate in forecasting thermal performance. In fact, moment analysis shows that, mathematically, thermal breakthrough is independent of parameters that primarily influence inert tracers. The most accurate prediction of thermal breakthrough using inert tracer alone was produced by treating hydrodynamic dispersion as a truly Fickian process with known and accurate mathematical models. Under this assumption, inert tracer data was matched by solving an inverse problem for non-uniform fracture aperture. Early arrival of the thermal front was predicted at the production, but was less accurate than using a combined inert/adsorbing tracer test. The spatial distribution of fluid flow paths in the plane of the fracture were identified using computational models, Fiber-Optic Distributed Temperature Sensing (FO-DTS), and Ground Penetrating Radar (GPR) imaging of saline tracer flow paths in the target fracture. Without exception, fluid flow was found to be concentrated in a roughly 1 m wide flow channel directly between the two wells. The

  15. A review of reservoir desiltation

    DEFF Research Database (Denmark)

    Brandt, Anders

    2000-01-01

    physical geography, hydrology, desilation efficiency, reservoir flushing, density-current venting, sediment slucing, erosion pattern, downstream effects, flow characteristics, sedimentation......physical geography, hydrology, desilation efficiency, reservoir flushing, density-current venting, sediment slucing, erosion pattern, downstream effects, flow characteristics, sedimentation...

  16. Reservoir sedimentation; a literature survey

    NARCIS (Netherlands)

    Sloff, C.J.

    1991-01-01

    A survey of literature is made on reservoir sedimentation, one of the most threatening processes for world-wide reservoir performance. The sedimentation processes, their impacts, and their controlling factors are assessed from a hydraulic engineering point of view with special emphasis on

  17. FRACTURED PETROLEUM RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Abbas Firoozabadi

    1999-06-11

    The four chapters that are described in this report cover a variety of subjects that not only give insight into the understanding of multiphase flow in fractured porous media, but they provide also major contribution towards the understanding of flow processes with in-situ phase formation. In the following, a summary of all the chapters will be provided. Chapter I addresses issues related to water injection in water-wet fractured porous media. There are two parts in this chapter. Part I covers extensive set of measurements for water injection in water-wet fractured porous media. Both single matrix block and multiple matrix blocks tests are covered. There are two major findings from these experiments: (1) co-current imbibition can be more efficient than counter-current imbibition due to lower residual oil saturation and higher oil mobility, and (2) tight fractured porous media can be more efficient than a permeable porous media when subjected to water injection. These findings are directly related to the type of tests one can perform in the laboratory and to decide on the fate of water injection in fractured reservoirs. Part II of Chapter I presents modeling of water injection in water-wet fractured media by modifying the Buckley-Leverett Theory. A major element of the new model is the multiplication of the transfer flux by the fractured saturation with a power of 1/2. This simple model can account for both co-current and counter-current imbibition and computationally it is very efficient. It can be orders of magnitude faster than a conventional dual-porosity model. Part II also presents the results of water injection tests in very tight rocks of some 0.01 md permeability. Oil recovery from water imbibition tests from such at tight rock can be as high as 25 percent. Chapter II discusses solution gas-drive for cold production from heavy-oil reservoirs. The impetus for this work is the study of new gas phase formation from in-situ process which can be significantly

  18. Reservoir engineering and hydrogeology

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    Summaries are included which show advances in the following areas: fractured porous media, flow in single fractures or networks of fractures, hydrothermal flow, hydromechanical effects, hydrochemical processes, unsaturated-saturated systems, and multiphase multicomponent flows. The main thrust of these efforts is to understand the movement of mass and energy through rocks. This has involved treating fracture rock masses in which the flow phenomena within both the fractures and the matrix must be investigated. Studies also address the complex coupling between aspects of thermal, hydraulic, and mechanical processes associated with a nuclear waste repository in a fractured rock medium. In all these projects, both numerical modeling and simulation, as well as field studies, were employed. In the theoretical area, a basic understanding of multiphase flow, nonisothermal unsaturated behavior, and new numerical methods have been developed. The field work has involved reservoir testing, data analysis, and case histories at a number of geothermal projects

  19. Chalk as a reservoir

    DEFF Research Database (Denmark)

    Fabricius, Ida Lykke

    basin, so stylolite formation in the chalk is controlled by effective burial stress. The stylolites are zones of calcite dissolution and probably are the source of calcite for porefilling cementation which is typical in water zone chalk and also affect the reservoirs to different extent. The relatively...... 50% calcite, leaving the remaining internal surface to the fine grained silica and clay. The high specific surface of these components causes clay- and silica rich intervals to have high irreducible water saturation. Although chalks typically are found to be water wet, chalk with mixed wettability...... stabilizes chemically by recrystallization. This process requires energy and is promoted by temperature. This recrystallization in principle does not influence porosity, but only specific surface, which decreases during recrystallization, causing permeability to increase. The central North Sea is a warm...

  20. Pacifiers: a microbial reservoir.

    Science.gov (United States)

    Comina, Elodie; Marion, Karine; Renaud, François N R; Dore, Jeanne; Bergeron, Emmanuelle; Freney, Jean

    2006-12-01

    The permanent contact between the nipple part of pacifiers and the oral microflora offers ideal conditions for the development of biofilms. This study assessed the microbial contamination on the surface of 25 used pacifier nipples provided by day-care centers. Nine were made of silicone and 16 were made of latex. The biofilm was quantified using direct staining and microscopic observations followed by scraping and microorganism counting. The presence of a biofilm was confirmed on 80% of the pacifier nipples studied. This biofilm was mature for 36% of them. Latex pacifier nipples were more contaminated than silicone ones. The two main genera isolated were Staphylococcus and Candida. Our results confirm that nipples can be seen as potential reservoirs of infections. However, pacifiers do have some advantages; in particular, the potential protection they afford against sudden infant death syndrome. Strict rules of hygiene and an efficient antibiofilm cleaning protocol should be established to answer the worries of parents concerning the safety of pacifiers.

  1. Melt Channel Formation in Paraffin With Applications to Lava Channels

    Science.gov (United States)

    Whitehead, J. A.; Mills, C. J.

    2005-12-01

    We present the results from laboratory experiments designed to explore channel formation caused by instabilities in fluid flow, and to provide a simple experimental basis to facilitate the extension of lava channel theory. Kelemen et. al. [1995] reported on a series of experiments that explored channel formation resulting from fluid instabilities caused by the ``reactive infiltration instability'' (RII). However, the material used in portions of their experiments was undesirable because of a poorly suited rheology. Therefore, our experiments were initiated as an extension of those earlier experiments, using instead a material with more robust rheological properties. The material chosen for this series of experiments is a paraffin with a freezing temperature of 4°C, which is transparent when liquid and opaque-white when frozen. The paraffin is pumped at a constant and controlled rate into a narrow gap between two circular plates, both with a diameter of ~51cm. The gap is open along the circumference of the plates, allowing the paraffin to flow out of the gap once it reaches the edge of the plate. The upper plate is constructed of Plexiglas to allow observation of the wax below, and it has a hole in the center through which the paraffin is pumped. The lower plate is constructed of aluminum, painted black, and kept at -5°C by circulating coolant through a reservoir below the it. As the paraffin, which is kept at 20°C before being pumped into the gap, flows over the cold lower plate, it begins to freeze and eventually fills up the gap between the plates. A single channel then forms, surrounded by solid paraffin, and the liquid being pumped in is transported via this channel to the edge of the plate. This is a stable state for all but the lowest flow rates attempted and verifies the results from the earlier work exploring the RII. We conducted experiments at different flows rates from 270mL/min to <30mL/min, and recorded the dimensions of the steady state channel

  2. Deterioro cognitivo leve: ¿dónde termina el envejecimiento normal y empieza la demencia?

    Directory of Open Access Journals (Sweden)

    Nilton Custodio

    2012-10-01

    Full Text Available Con el aumento de la prevalencia de demencia en el mundo, debemos poner especial atención a la evaluación diagnóstica de estadios previos a la demencia. El deterioro cognitivo leve (DCL podría ser considerado un estadio precoz de demencia, en especial de la enfermedad de Alzheimer (AD; por lo que consideramos importante un diagnóstico adecuado, mediante la utilización de instrumentos y técnicas fiables y sensibles, que permitan discriminar entre sujetos con envejecimiento normal y patológico. Los estudios epidemiológicos muestran una elevada prevalencia de DCL en la población general. Asimismo, se ha documentado la progresión de DCL a demencia y EA, sobre todo en sujetos con DCL del tipo amnésico. La edad, el estado de portador del APOE-ε4, la atrofia del hipocampo en resonancia magnética y la presencia de algunos biomarcadores en líquido cefalorraquídeo parecen influir en la conversión. Se sugiere que el estudio de pacientes con sospecha de DCL sea el mismo que se emplea en la sospecha de demencia y EA. La evaluación neuropsicológica es la única prueba que permite confirmar el diagnóstico y nos ayuda a realizar una adecuada clasificación de los subtipos de DCL: amnésico, multidominio y monodominio no amnésico.

  3. Advances in photonic reservoir computing

    Directory of Open Access Journals (Sweden)

    Van der Sande Guy

    2017-05-01

    Full Text Available We review a novel paradigm that has emerged in analogue neuromorphic optical computing. The goal is to implement a reservoir computer in optics, where information is encoded in the intensity and phase of the optical field. Reservoir computing is a bio-inspired approach especially suited for processing time-dependent information. The reservoir’s complex and high-dimensional transient response to the input signal is capable of universal computation. The reservoir does not need to be trained, which makes it very well suited for optics. As such, much of the promise of photonic reservoirs lies in their minimal hardware requirements, a tremendous advantage over other hardware-intensive neural network models. We review the two main approaches to optical reservoir computing: networks implemented with multiple discrete optical nodes and the continuous system of a single nonlinear device coupled to delayed feedback.

  4. Quaternary over-elevated torrential channels. Characteristics and depositional significance: the Maresme model (Catalonia, NE Spain)

    Science.gov (United States)

    Colombo, Ferran; Rivero, Lluis

    2017-10-01

    Channel-levee deposits that occur in some large sand-dominated fluvial systems are commonly elevated above the surrounding floodplain. However, the over-elevation processes of small and isolated fluvial channels are poorly documented. The Maresme zone located NE of Barcelona (Spain) offers many examples of small over-elevated channels. This area is characterised by weathered granodiorites forming a thick coarse-grained sand-dominated regolith, which was initially covered by dense forests. In the XVIII and XIX centuries human activity led to the destruction of the vegetal cover, resulting in subsequent erosion and in the intense remobilisation of sediments during storms. Thus, large amounts of sand were transported during historical times. The intermittent discharges were confined to short (few km) and straight channels with high and uncommon gradients from 3.2 to 3.4%. These discharges flowed at high velocities towards the Mediterranean Sea, the regional base-level. High infiltration rates contributed to the accretion of sandy sediments along the channels coevally with levee development. This sandy lithosome, which is usually elevated above the surrounding floodplain, displays a characteristic convex-up cross section.

  5. Applicability of Donnan equilibrium theory at nanochannel-reservoir interfaces.

    Science.gov (United States)

    Tian, Huanhuan; Zhang, Li; Wang, Moran

    2015-08-15

    Understanding ionic transport in nanochannels has attracted broad attention from various areas in energy and environmental fields. In most pervious research, Donnan equilibrium has been applied widely to nanofluidic systems to obtain ionic concentration and electrical potential at channel-reservoir interfaces; however, as well known that Donnan equilibrium is derived from classical thermodynamic theories with equilibrium assumptions. Therefore the applicability of the Donnan equilibrium may be questionable when the transport at nanochannel-reservoir interface is strongly non-equilibrium. In this work, the Poisson-Nernst-Planck model for ion transport is numerically solved to obtain the exact distributions of ionic concentration and electrical potential. The numerical results are quantitatively compared with the Donnan equilibrium predictions. The applicability of Donnan equilibrium is therefore justified by changing channel length, reservoir ionic concentration, surface charge density and channel height. The results indicate that the Donnan equilibrium is not applicable for short nanochannels, large concentration difference and wide openings. A non-dimensional parameter, Q factor, is proposed to measure the non-equilibrium extent and the relation between Q and the working conditions is studied in detail. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. An Archaeological Reconnaissance of Proposed Levees, Water-Oriented Recreation Facilities and Borrow Areas Downstream from the Harry S. Truman Dam and Reservoir, Benton County, Missouri: 1980

    Science.gov (United States)

    1988-01-01

    uniface with bat- Chopper Chopping tered edges Flake with deeply serrated Denticulate Cutting and slicing, sawing, edges shredding Thick biface... uniface with Heavy duty scraper Heavy duty woodworking beveled, unifacially worn edge Thin biface/ uniface with bev- Light duty scraper Hide preparation...Reamer Reaming, grooving worked and worn bit Tool with narrow spur sowing Graver Scoring, graving, bone and use wear woodworking Biface or uniface with

  7. The Morphometry of the Deep-Water Sinuous Mendocino Channel and the Immediate Environs, Northeastern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    James V. Gardner

    2017-11-01

    Full Text Available Mendocino Channel, a deep-water sinuous channel located along the base of Gorda Escarpment, was for the first time completely mapped with a multibeam echosounder. This study uses newly acquired multibeam bathymetry and backscatter, together with supporting multichannel seismic and sediment core data to quantitatively describe the morphometry of the entire Mendocino Channel and to explore the age and possible causes that may have contributed to the formation and maintenance of the channel. The first 42 km of the channel is a linear reach followed for the next 83.8 km by a sinuous reach. The sinuous reach has a sinuosity index of 1.66 before it changes back to a linear reach for the next 22.2 km. A second sinuous reach is 40.2 km long and the two reaches are separated by a crevasse splay and a large landslide that deflected the channel northwest towards Gorda Basin. Both sinuous reaches have oxbow bends, cut-off meanders, interior and exterior terraces and extensive levee systems. The lower sinuous reach becomes more linear for the next 22.2 km before the channel relief falls below the resolution of the data. Levees suddenly decrease in height above the channel floor mid-way along the lower linear reach close to where the channel makes a 90° turn to the southwest. The entire channel floor is smooth at the resolution of the data and only two large mounds and one large sediment pile were found on the channel floor. The bathymetry and acoustic backscatter, together with previously collected seismic data and box and piston cores provide details to suggest Mendocino Channel may be no older than early Quaternary. A combination of significant and numerous earthquakes and wave-loading resuspension by storms are the most likely processes that generated turbidity currents that have formed and modified Mendocino Channel.

  8. Gravity observations for hydrocarbon reservoir monitoring

    NARCIS (Netherlands)

    Glegola, M.A.

    2013-01-01

    In this thesis the added value of gravity observations for hydrocarbon reservoir monitoring and characterization is investigated. Reservoir processes and reservoir types most suitable for gravimetric monitoring are identified. Major noise sources affecting time-lapse gravimetry are analyzed. The

  9. Channel Power in Multi-Channel Environments

    NARCIS (Netherlands)

    M.G. Dekimpe (Marnik); B. Skiera (Bernd)

    2004-01-01

    textabstractIn the literature, little attention has been paid to instances where companies add an Internet channel to their direct channel portfolio. However, actively managing multiple sales channels requires knowing the customers’ channel preferences and the resulting channel power. Two key

  10. Assessing ways to combat eutrophication in a Chinese drinking water reservoir using SWAT

    DEFF Research Database (Denmark)

    Nielsen, Anders; Trolle, Dennis; Me, W

    2013-01-01

    both point sources and surface activities within the watershed of a reservoir. We expanded the ordinary Soil Water Assessment Tool – (SWAT) with a widely used empirical equation to estimate total phosphorus (TP) concentrations in lakes and reservoirs. Subsequently, we examined the effects of changes...... model performance and nutrient transport pathways, which are challenged by a complex artificially altered water infrastructure in the form of ditches, channels and ponds in monsoon-influenced subtropical watersheds....

  11. Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX); Gilbert, Bob (University of Texas at Austin, Austin, TX); Lake, Larry W. (University of Texas at Austin, Austin, TX); Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX); Thomas, Sunil G. (University of Texas at Austin, Austin, TX); Rightley, Michael J.; Rodriguez, Adolfo (University of Texas at Austin, Austin, TX); Klie, Hector (University of Texas at Austin, Austin, TX); Banchs, Rafael (University of Texas at Austin, Austin, TX); Nunez, Emilio J. (University of Texas at Austin, Austin, TX); Jablonowski, Chris (University of Texas at Austin, Austin, TX)

    2006-11-01

    The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging

  12. Well testing in gas hydrate reservoirs

    OpenAIRE

    Kome, Melvin Njumbe

    2015-01-01

    Reservoir testing and analysis are fundamental tools in understanding reservoir hydraulics and hence forecasting reservoir responses. The quality of the analysis is very dependent on the conceptual model used in investigating the responses under different flowing conditions. The use of reservoir testing in the characterization and derivation of reservoir parameters is widely established, especially in conventional oil and gas reservoirs. However, with depleting conventional reserves, the ...

  13. Sediment Characteristics of Tennessee Streams and Reservoirs

    National Research Council Canada - National Science Library

    Trimble, Stanley W; Carey, William P

    1984-01-01

    Suspended-sediment and reservoir sedimentation data have been analyzed to determine sediment yields and transport characteristics of Tennessee streams Data from 31 reservoirs plus suspended-sediment...

  14. Starburst Channels

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] Figure 1 Translucent carbon dioxide ice covers the polar regions of Mars seasonally. It is warmed and sublimates (evaporates) from below, and escaping gas carves a numerous channel morphologies. In this example (figure 1) the channels form a 'starburst' pattern, radiating out into feathery extensions. The center of the pattern is being buried with dust and new darker dust fans ring the outer edges. This may be an example of an expanding morphology, where new channels are formed as the older ones fill and are no longer efficiently channeling the subliming gas out. Observation Geometry Image PSP_003443_0980 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on 21-Apr-2007. The complete image is centered at -81.8 degrees latitude, 76.2 degrees East longitude. The range to the target site was 247.1 km (154.4 miles). At this distance the image scale is 24.7 cm/pixel (with 1 x 1 binning) so objects 74 cm across are resolved. The image shown here has been map-projected to 25 cm/pixel. The image was taken at a local Mars time of 04:52 PM and the scene is illuminated from the west with a solar incidence angle of 71 degrees, thus the sun was about 19 degrees above the horizon. At a solar longitude of 223.4 degrees, the season on Mars is Northern Autumn.

  15. Changes to the Bakomi Reservoir

    Directory of Open Access Journals (Sweden)

    Kubinský Daniel

    2014-08-01

    Full Text Available This article is focused on the analysis and evaluation of the changes of the bottom of the Bakomi reservoir, the total volume of the reservoir, ecosystems, as well as changes in the riparian zone of the Bakomi reservoir (situated in the central Slovakia. Changes of the water component of the reservoir were subject to the deposition by erosion-sedimentation processes, and were identifed on the basis of a comparison of the present relief of the bottom of reservoir obtained from feld measurements (in 2011 with the relief measurements of the bottom obtained from the 1971 historical maps, (i.e. over a period of 40 years. Changes of landscape structures of the riparian zone have been mapped for the time period of 1949–2013; these changes have been identifed with the analysis of ortophotomaps and the feld survey. There has been a signifcant rise of disturbed shores with low herb grassland. Over a period of 40 years, there has been a deposition of 667 m3 of sediments. The results showed that there were no signifcant changes in the local ecosystems of the Bakomi reservoir in comparison to the other reservoirs in the vicinity of Banská Štiavnica.

  16. TRITIUM RESERVOIR STRUCTURAL PERFORMANCE PREDICTION

    Energy Technology Data Exchange (ETDEWEB)

    Lam, P.S.; Morgan, M.J

    2005-11-10

    The burst test is used to assess the material performance of tritium reservoirs in the surveillance program in which reservoirs have been in service for extended periods of time. A materials system model and finite element procedure were developed under a Savannah River Site Plant-Directed Research and Development (PDRD) program to predict the structural response under a full range of loading and aged material conditions of the reservoir. The results show that the predicted burst pressure and volume ductility are in good agreement with the actual burst test results for the unexposed units. The material tensile properties used in the calculations were obtained from a curved tensile specimen harvested from a companion reservoir by Electric Discharge Machining (EDM). In the absence of exposed and aged material tensile data, literature data were used for demonstrating the methodology in terms of the helium-3 concentration in the metal and the depth of penetration in the reservoir sidewall. It can be shown that the volume ductility decreases significantly with the presence of tritium and its decay product, helium-3, in the metal, as was observed in the laboratory-controlled burst tests. The model and analytical procedure provides a predictive tool for reservoir structural integrity under aging conditions. It is recommended that benchmark tests and analysis for aged materials be performed. The methodology can be augmented to predict performance for reservoir with flaws.

  17. A reservoir simulation approach for modeling of naturally fractured reservoirs

    Directory of Open Access Journals (Sweden)

    H. Mohammadi

    2012-12-01

    Full Text Available In this investigation, the Warren and Root model proposed for the simulation of naturally fractured reservoir was improved. A reservoir simulation approach was used to develop a 2D model of a synthetic oil reservoir. Main rock properties of each gridblock were defined for two different types of gridblocks called matrix and fracture gridblocks. These two gridblocks were different in porosity and permeability values which were higher for fracture gridblocks compared to the matrix gridblocks. This model was solved using the implicit finite difference method. Results showed an improvement in the Warren and Root model especially in region 2 of the semilog plot of pressure drop versus time, which indicated a linear transition zone with no inflection point as predicted by other investigators. Effects of fracture spacing, fracture permeability, fracture porosity, matrix permeability and matrix porosity on the behavior of a typical naturally fractured reservoir were also presented.

  18. THE SURDUC RESERVOIR (ROMANIA

    Directory of Open Access Journals (Sweden)

    Niculae Iulian TEODORESCU

    2008-06-01

    Full Text Available The Surduc reservoir was projected to ensure more water when water is scarce and to thus provide especially the city Timisoara, downstream of it with water.The accumulation is placed on the main affluent of the Bega river, Gladna in the upper part of its watercourse.The dam behind which this accumulation was created is of a frontal type made of enrochements with a masque made of armed concrete on the upstream part and protected/sustained by grass on the downstream. The dam is 130m long on its coping and a constructed height of 34 m. It is also endowed with spillway for high water and two bottom outlets formed of two conduits, at the end of which is the microplant. The second part of my paper deals with the hydrometric analysis of the Accumulation Surduc and its impact upon the flow, especially the maximum run-off. This influence is exemplified through the high flood from the 29th of July 1980, the most significant flood recorded in the basin with an apparition probability of 0.002%.

  19. Quality and dose optimized CT trauma protocol. Recommendation from a university level-I trauma center

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, Johannes; Boening, Georg; Rotzinger, Roman; Freyhardt, Patrick; Streitparth, Florian [Charite School of Medicine and Univ. Hospital Berlin (Germany). Dept. of Radiology; Kaul, David [Charite School of Medicine and Univ. Hospital Berlin (Germany). Dept. of Radiation Oncology; Schwabe, Philipp [Charite School of Medicine and Univ. Hospital Berlin (Germany). Dept. of Trauma Surgery; Maurer, Martin H. [Inselspital Bern (Switzerland). Dept. of Diagnostic, Interventional and Pediatric Radiology; Renz, Diane Miriam [Univ. Hospital Jena (Germany). Inst. of Diagnostic and Interventional Radiology

    2017-09-15

    As a supra-regional level-I trauma center, we evaluated computed tomography (CT) acquisitions of polytraumatized patients for quality and dose optimization purposes. Adapted statistical iterative reconstruction [(AS)IR] levels, tube voltage reduction as well as a split-bolus contrast agent (CA) protocol were applied. Materials and Methods 61 patients were split into 3 different groups that differed with respect to tube voltage (120 - 140 kVp) and level of applied ASIR reconstruction (ASIR 20 - 50%). The CT protocol included a native acquisition of the head followed by a single contrast-enhanced acquisition of the whole body (64-MSCT). CA (350 mg/ml iodine) was administered as a split bolus injection of 100 ml (2 ml/s), 20 ml NaCl (1 ml/s), 60 ml (4 ml/s), 40 ml NaCl (4 ml/s) with a scan delay of 85s to detect injuries of both the arterial system and parenchymal organs in a single acquisition. Both the quantitative (SNR/CNR) and qualitative (5-point Likert scale) image quality was evaluated in parenchymal organs that are often injured in trauma patients. Radiation exposure was assessed. The use of IR combined with a reduction of tube voltage resulted in good qualitative and quantitative image quality and a significant reduction in radiation exposure of more than 40% (DLP 1087 vs. 647 mGy x cm). Image quality could be improved due to a dedicated protocol that included different levels of IR adapted to different slice thicknesses, kernels and the examined area for the evaluation of head, lung, body and bone injury patterns. In synopsis of our results, we recommend the implementation of a polytrauma protocol with a tube voltage of 120 kVp and the following IR levels: cCT 5mm: ASIR 20; cCT 0.625 mm: ASIR 40; lung 2.5 mm: ASIR 30, body 5 mm: ASIR 40; body 1.25 mm: ASIR 50; body 0.625 mm: ASIR 0. A dedicated adaptation of the CT trauma protocol (level of reduction of tube voltage and of IR) according to the examined body region (head, lung, body, bone) combined with a

  20. Valores de lipasa en pancreatitis biliar leve y su implicación en el manejo quirúrgico temprano

    OpenAIRE

    Angamarca Angamarca, Edison Fernando

    2016-01-01

    Introducción: la pancreatitis aguda biliar leve es una patología frecuente, con evolución favorable, si se evita complicaciones: pancreatitis recurrente, colecistitis, colangitis, colédocolitiasis, prevenibles realizando un tratamiento quirúrgico temprano; ¿Cuándo realizar la intervención? no está definida. El presente trabajo revisa la evolución de la enzima lipasa hasta su normalización y el tratamiento quirúrgico. Método: se realizó un estudio descriptivo prospectivo, de enero a diciem...

  1. Análisis de la eficiencia y seguridad de un protocolo de alta precoz en pancreatitis aguda leve

    OpenAIRE

    Serra Pla, Sheila

    2016-01-01

    OBJECTIVO: las primeras 24 horas de evolución son cruciales en los pacientes con diagnóstico de pancreatitis aguda (PA) ya que este es el periodo en el que un mayor número de pacientes presenta un fallo orgánico. Esto sugiere que los pacientes con PA leve (PAL) podrían ser identificados y dados de alta precozmente. El objetivo de este estudio es demostrar la viabilidad y seguridad de un protocolo de alta precoz en PAL. MATERIAL Y MÉTODOS: Estudio observacional prospectivo en un hospital d...

  2. Análisis de la eficiencia y seguridad de un protocolo de alta precoz en pancreatitis aguda leve /

    OpenAIRE

    Serra Pla, Sheila,

    2016-01-01

    OBJECTIVO: las primeras 24 horas de evolución son cruciales en los pacientes con diagnóstico de pancreatitis aguda (PA) ya que este es el periodo en el que un mayor número de pacientes presenta un fallo orgánico. Esto sugiere que los pacientes con PA leve (PAL) podrían ser identificados y dados de alta precozmente. El objetivo de este estudio es demostrar la viabilidad y seguridad de un protocolo de alta precoz en PAL. MATERIAL Y MÉTODOS: Estudio observacional prospectivo en un hospital de te...

  3. Análises moleculares em gestantes com diabete e hiperglicemia leve e em seus recém-nascidos

    OpenAIRE

    Gelaleti, Rafael Bottaro [UNESP

    2012-01-01

    O grupo IB corresponde a gestantes portadoras de hiperglicemia leve, ou seja, gestantes que apresentam rastreamento positivo, mas diagnóstico negativo para diabete gestacional (DMG) teste de tolerância a glicose (TTG100g normal), e resposta alterada no perfil glicêmico (PG). Este grupo foi, acidentalmente, identificado em 1983, quando projeto prospectivo foi desenvolvido para padronização do PG comparando-o com o TTG100g no diagnóstico do diabete na gestação. Essas gestantes apresentam resist...

  4. Understanding the True Stimulated Reservoir Volume in Shale Reservoirs

    KAUST Repository

    Hussain, Maaruf

    2017-06-06

    Successful exploitation of shale reservoirs largely depends on the effectiveness of hydraulic fracturing stimulation program. Favorable results have been attributed to intersection and reactivation of pre-existing fractures by hydraulically-induced fractures that connect the wellbore to a larger fracture surface area within the reservoir rock volume. Thus, accurate estimation of the stimulated reservoir volume (SRV) becomes critical for the reservoir performance simulation and production analysis. Micro-seismic events (MS) have been commonly used as a proxy to map out the SRV geometry, which could be erroneous because not all MS events are related to hydraulic fracture propagation. The case studies discussed here utilized a fully 3-D simulation approach to estimate the SRV. The simulation approach presented in this paper takes into account the real-time changes in the reservoir\\'s geomechanics as a function of fluid pressures. It is consisted of four separate coupled modules: geomechanics, hydrodynamics, a geomechanical joint model for interfacial resolution, and an adaptive re-meshing. Reservoir stress condition, rock mechanical properties, and injected fluid pressure dictate how fracture elements could open or slide. Critical stress intensity factor was used as a fracture criterion governing the generation of new fractures or propagation of existing fractures and their directions. Our simulations were run on a Cray XC-40 HPC system. The studies outcomes proved the approach of using MS data as a proxy for SRV to be significantly flawed. Many of the observed stimulated natural fractures are stress related and very few that are closer to the injection field are connected. The situation is worsened in a highly laminated shale reservoir as the hydraulic fracture propagation is significantly hampered. High contrast in the in-situ stresses related strike-slip developed thereby shortens the extent of SRV. However, far field nature fractures that were not connected to

  5. Chickamauga reservoir embayment study - 1990

    Energy Technology Data Exchange (ETDEWEB)

    Meinert, D.L.; Butkus, S.R.; McDonough, T.A.

    1992-12-01

    The objectives of this report are three-fold: (1) assess physical, chemical, and biological conditions in the major embayments of Chickamauga Reservoir; (2) compare water quality and biological conditions of embayments with main river locations; and (3) identify any water quality concerns in the study embayments that may warrant further investigation and/or management actions. Embayments are important areas of reservoirs to be considered when assessments are made to support water quality management plans. In general, embayments, because of their smaller size (water surface areas usually less than 1000 acres), shallower morphometry (average depth usually less than 10 feet), and longer detention times (frequently a month or more), exhibit more extreme responses to pollutant loadings and changes in land use than the main river region of the reservoir. Consequently, embayments are often at greater risk of water quality impairments (e.g. nutrient enrichment, filling and siltation, excessive growths of aquatic plants, algal blooms, low dissolved oxygen concentrations, bacteriological contamination, etc.). Much of the secondary beneficial use of reservoirs occurs in embayments (viz. marinas, recreation areas, parks and beaches, residential development, etc.). Typically embayments comprise less than 20 percent of the surface area of a reservoir, but they often receive 50 percent or more of the water-oriented recreational use of the reservoir. This intensive recreational use creates a potential for adverse use impacts if poor water quality and aquatic conditions exist in an embayment.

  6. Reservoir characterization of Pennsylvanian Sandstone Reservoirs. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.

    1992-09-01

    This annual report describes the progress during the second year of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description and scale-up procedures; (ii) outcrop investigation; (iii) in-fill drilling potential. The first section describes the methods by which a reservoir can be characterized, can be described in three dimensions, and can be scaled up with respect to its properties, appropriate for simulation purposes. The second section describes the progress on investigation of an outcrop. The outcrop is an analog of Bartlesville Sandstone. We have drilled ten wells behind the outcrop and collected extensive log and core data. The cores have been slabbed, photographed and the several plugs have been taken. In addition, minipermeameter is used to measure permeabilities on the core surface at six inch intervals. The plugs have been analyzed for the permeability and porosity values. The variations in property values will be tied to the geological descriptions as well as the subsurface data collected from the Glen Pool field. The third section discusses the application of geostatistical techniques to infer in-fill well locations. The geostatistical technique used is the simulated annealing technique because of its flexibility. One of the important reservoir data is the production data. Use of production data will allow us to define the reservoir continuities, which may in turn, determine the in-fill well locations. The proposed technique allows us to incorporate some of the production data as constraints in the reservoir descriptions. The technique has been validated by comparing the results with numerical simulations.

  7. Petroleum reservoir data for testing simulation models

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, J.M.; Harrison, W.

    1980-09-01

    This report consists of reservoir pressure and production data for 25 petroleum reservoirs. Included are 5 data sets for single-phase (liquid) reservoirs, 1 data set for a single-phase (liquid) reservoir with pressure maintenance, 13 data sets for two-phase (liquid/gas) reservoirs and 6 for two-phase reservoirs with pressure maintenance. Also given are ancillary data for each reservoir that could be of value in the development and validation of simulation models. A bibliography is included that lists the publications from which the data were obtained.

  8. Urban Floods in Lowlands—Levee Systems, Unplanned Urban Growth and River Restoration Alternative: A Case Study in Brazil

    Directory of Open Access Journals (Sweden)

    Marcelo Gomes Miguez

    2015-08-01

    Full Text Available The development of cities has always had a very close relation with water. However, cities directly impact land use patterns and greatly change natural landscapes, aggravating floods. Considering this situation, this paper intends to discuss lowland occupation and city sustainability in what regards urban stormwater management, fluvial space, and river restoration, aiming at minimizing flood risks and improving natural and built environment conditions. River plains tend to be attractive places for a city to grow. From ancient times, levees have been used to protect lowland areas along major watercourses to allow their occupation. However, urban rivers demand space for temporary flood storage. From a systemic point of view, levees along extensive river reaches act as canalization works, limiting river connectivity with flood plains, rising water levels, increasing overtopping risks and transferring floods downstream. Departing from this discussion, four case studies in the Iguaçu-Sarapuí River Basin, a lowland area of Rio de Janeiro State, Brazil, are used to compose a perspective in which the central point refers to the need of respecting watershed limits and giving space to rivers. Different aspects of low-lying city planning are discussed and analyzed concerning the integration of the built and natural environments.

  9. A utilização de betões leves em estruturas mistas aço-betão

    OpenAIRE

    Cruz, Paulo J. S.; Valente, Isabel

    2008-01-01

    Neste artigo são apresentados alguns dos principais resultados dos trabalhos de investigação que, ao longo dos últimos anos, têm sido desenvolvidos na Universidade do Minho com vista ao estudo da aplicabilidade de betões leves em estruturas mistas aço-betão. Essa investigação, com um carácter bastante aprofundado e um âmbito muito alargado compreende os seguintes ensaios: de caracterização dos agregados leves, de caracterização mecânica e de durabilidade de betões leves de várias resistências...

  10. The Transition of Benthic Nutrient Sources after Planned Levee Breaches Adjacent to Upper Klamath and Agency Lakes, Oregon

    Science.gov (United States)

    Kuwabara, James S.; Topping, Brent R.; Carter, James L.; Parcheso, Francis; Cameron, Jason M.; Asbill, Jessica R.; Fend, Steven V.; Duff, John H.; Engelstad, Anita C.

    2010-01-01

    Four sampling trips were coordinated after planned levee breaches that hydrologically reconnected both Upper Klamath Lake and Agency Lake, Oregon, to adjacent wetlands. Sets of nonmetallic pore-water profilers were deployed during these trips in November 2007, June 2008, May 2009, and July 2009. Deployments temporally spanned the annual cyanophyte bloom of Aphanizomenon flos-aquae (AFA) and spatially involved three lake and four wetland sites. Profilers, typically deployed in triplicate at each lake or wetland site, provided high-resolution (centimeter-scale) estimates of the vertical concentration gradients for diffusive-flux determinations. Estimates based on molecular diffusion may underestimate benthic flux because solute transport across the sediment-water interface can be enhanced by processes including bioturbation, bioirrigation and groundwater advection. Water-column and benthic samples were also collected to help interpret spatial and temporal trends in diffusive-flux estimates. Data from these samples complement taxonomic and geochemical analyses of bottom-sediments taken from Upper Klamath Lake (UKL) in prior studies. This ongoing study provides information necessary for developing process-interdependent solute-transport models for the watershed (that is, models integrating physical, geochemical, and biological processes) and supports efforts to evaluate remediation or load-allocation strategies. To augment studies funded by the U.S. Bureau of Reclamation (USBR), the Department of the Interior supported an additional full deployment of pore-water profilers in November 2007 and July 2009, immediately following the levee breaches and after the crash of the annual summer AFA bloom. As observed consistently since 2006, benthic flux of 0.2-micron filtered, soluble reactive phosphorus (that is, biologically available phosphorus, primarily as orthophosphate; SRP) was consistently positive (that is, out of the sediment into the overlying water column) and

  11. Gravity observations for hydrocarbon reservoir monitoring

    OpenAIRE

    Glegola, M.A.

    2013-01-01

    In this thesis the added value of gravity observations for hydrocarbon reservoir monitoring and characterization is investigated. Reservoir processes and reservoir types most suitable for gravimetric monitoring are identified. Major noise sources affecting time-lapse gravimetry are analyzed. The added value of gravity data for reservoir monitoring and characterization is analyzed within closed-loop reservoir management concept. Synthetic 2D and 3D numerical experiments are performed where var...

  12. Nitrogen and phosphorus in cascade multi-system tropical reservoirs: water and sediment

    Directory of Open Access Journals (Sweden)

    Pompêo Marcelo

    2017-09-01

    Full Text Available The aim of this research was to analyze the horizontal spatial heterogeneity of both water and superficial sediment quality among and within the reservoirs of the Cantareira System (CS, focusing on concentrations of N and P, attributed to the dumping of raw domestic sewage into water bodies, which is the main cause of water pollution in São Paulo State (Brazil. The CS is a multi-system complex composed of five interconnected reservoirs, with water transported by gravity through 48 km of tunnels and channels. From the last reservoir of the CS, with an output of 33 m3 s−1, the water is conducted to a water treatment plant, producing half of the water consumed by 19 million people inhabiting São Paulo city. The upstream reservoirs are more eutrophic than the downstream ones. Data also suggest that the low phytoplankton biomass (ranging from 0.9 to 14.4 μg dm−3 is regulated by the low nutrient availability, mainly of phosphorus (TP ranging from below the detection limit, <9.0 μg dm−3, to 47.3 μg dm−3. For water, the DIN/TP ratios values range from 19 to 380. The upstream reservoirs function as nutrient accumulators and the sediment is the main compartment in which P and N are stored. Although the reservoirs are located in different river basins and are not in sequence along the same river, the results suggest a marked gradient between the reservoirs, with features similar to those of cascade reservoirs. The large volumes flowing through the canals and tunnels could explain the observed pattern. The CS reservoirs can therefore be considered multi-system reservoirs in cascade, constituting a particular case of multi-system reservoirs.

  13. Valorização de resíduos da indústria da celulose na produção de agregados leves

    OpenAIRE

    Pinto, Susana de Jesus Fernandes

    2005-01-01

    Este trabalho tem como objectivo estudar a aplicação industrial de um conjunto de resíduos da indústria da celulose (lamas primárias e biológicas, dregs e grits) no processo de produção de agregados leves de argila expandida. A metodologia experimental envolveu quatro etapas: recolha e caracterização das matérias primas; incorporação dos resíduos no fabrico de agregados leves; ensaios industriais e caracterização final dos produtos obtidos. As formulações desenvolvidas envol...

  14. Desenvolvimento de pastas leves utilizando incorporadores de ar para aplicação em poços de petróleo

    OpenAIRE

    Santos, Herculana Torres dos

    2013-01-01

    A cimentação é uma das operações mais importantes realizadas durante a fase de construção de um poço de petróleo, pois tem o objetivo de vedar zonas permeáveis e fornecer suporte para a coluna de revestimento. Zonas de interesse depletadas ou com baixa pressão de fratura requerem pastas cimentantes de baixa densidade. Métodos tradicionais para produzir pastas leves incluem a formação de espumas, o uso de microesferas ocas de vidro ou de aditivos leves. O objetivo desse trabalho é estudar past...

  15. Targeted electrohydrodynamic printing for micro-reservoir drug delivery systems

    International Nuclear Information System (INIS)

    Hwang, Tae Heon; Kim, Jin Bum; Yang, Da Som; Ryu, WonHyoung; Park, Yong-il

    2013-01-01

    Microfluidic drug delivery systems consisting of a drug reservoir and microfluidic channels have shown the possibility of simple and robust modulation of drug release rate. However, the difficulty of loading a small quantity of drug into drug reservoirs at a micro-scale limited further development of such systems. Electrohydrodynamic (EHD) printing was employed to fill micro-reservoirs with controlled amount of drugs in the range of a few hundreds of picograms to tens of micrograms with spatial resolution of as small as 20 µm. Unlike most EHD systems, this system was configured in combination with an inverted microscope that allows in situ targeting of drug loading at micrometer scale accuracy. Methylene blue and rhodamine B were used as model drugs in distilled water, isopropanol and a polymer solution of a biodegradable polymer and dimethyl sulfoxide (DMSO). Also tetracycline-HCl/DI water was used as actual drug ink. The optimal parameters of EHD printing to load an extremely small quantity of drug into microscale drug reservoirs were investigated by changing pumping rates, the strength of an electric field and drug concentration. This targeted EHD technique was used to load drugs into the microreservoirs of PDMS microfluidic drug delivery devices and their drug release performance was demonstrated in vitro. (paper)

  16. Determination of heterogeneity by high-resolution seismic reservoir characterization in the heavy oil Temblor reservoir of Coalinga Field, California

    Science.gov (United States)

    Mahapatra, Sailendra Nath

    The research focuses on analysis and subsurface imaging of siliciclastics rocks on steam-affected 3D poststack seismic data, merged from different vintages, from the Temblor Formation in the Coalinga heavy oil reservoir in the San Joaquin basin, California. The objective was identification, delineation, and demarcation of reservoir heterogeneities by seismostratigraphic and seismogeomorphic analysis. The proximity of the San Andreas Transforms greatly controlled basin evolution and caused substantial reservoir heterogeneity by changing the depositional environment from shallow marine to near-shore fluvial. Moreover, two unconformities dissect the reservoir interval. The seismic dataset exhibits erratic, distorted reflection strengths and amplitudes caused by steam-injection-aided production. A petrophysical analysis based on Gassmann fluid substitution suggests a 27% P-wave velocity decrease in steam-saturated intervals. Seismic to well log ties were problematic and vexing due to the resulting statics, wavelet changes, and line mismatches. Mapping and flattening on a deeper horizon, however, allowed mapping of the internal unconformities and well ties which were crucial for seismostratigraphic sequence identification. Visualization of seismic attributes brought out stratification patterns and two distinct, laterally and vertically extensive, porous, and interconnected facies tracts interpreted as incised valley fills and tidal-to-subtidal deposits as evidenced by bright, steam related amplitudes. Seismic attribute analysis, Geobody Visualization and Interpretation, and structure and isochron maps brought out two prominent channel-systems, recut and restacked in the central part of the area. These deposits were identified on seismic data and correlated to high-gamma coarsening-upward sands on logs and cores. The deeper one, shifting towards SSE with depth, lies between the Base Temblor and Buttonbed unconformities both in the southwestern and northwestern parts of

  17. Reservoir-induced seismicity at Castanhao reservoir, NE Brazil

    Science.gov (United States)

    Nunes, B.; do Nascimento, A.; Ferreira, J.; Bezerra, F.

    2012-04-01

    Our case study - the Castanhão reservoir - is located in NE Brazil on crystalline rock at the Borborema Province. The Borborema Province is a major Proterozoic-Archean terrain formed as a consequence of convergence and collision of the São Luis-West Africa craton and the São Francisco-Congo-Kasai cratons. This reservoir is a 60 m high earth-filled dam, which can store up to 4.5 billion m3 of water. The construction begun in 1990 and finished in October 2003.The first identified reservoir-induced events occurred in 2003, when the water level was still low. The water reached the spillway for the first time in January 2004 and, after that, an increase in seismicity occured. The present study shows the results of a campaign done in the period from November 19th, 2009 to December 31th, 2010 at the Castanhão reservoir. We deployed six three-component digital seismographic station network around one of the areas of the reservoir. We analyzed a total of 77 events which were recorded in at least four stations. To determine hypocenters and time origin, we used HYPO71 program (Lee & Lahr, 1975) assuming a half-space model with following parameters: VP= 5.95 km/s and VP/VS=1.73. We also performed a relocation of these events using HYPODD (Waldhauser & Ellsworth, 2000) programme. The input data used we used were catalogue data, with all absolute times. The results from the spatio-temporal suggest that different clusters at different areas and depths are triggered at different times due to a mixture of: i - pore pressure increase due to diffusion and ii - increase of pore pressure due to the reservoir load.

  18. Redesigning reservoir compensation releases for ecological beenfit

    Science.gov (United States)

    Maynard, Carly

    2010-05-01

    River regulation is commonplace in England and much of the UK. Regulation for the purposes of public water supply causes flows downstream of a reservoir to be attenuated and the flow regime of the channel to be altered. The impact of channel impoundment on a small, upland UK river, has been assessed and methods for mitigation of ecological impacts explored. The method utilised a unique macroinvertebrate data set for pre- and post-impoundment periods to quantify the impact of Derwent Reservoir and the steady, continuous compensation release into the River Derwent, Northumberland. Impacts on the hydrological regime were also investigated and links drawn between changes in flow regime and changes in macroinvertebrate richness and diversity as a result of impoundment. In response to the claim that the impoundment has caused a change in flow regime and had deleterious effects on fish and macroinvertebrates, a compensation redesign tool (CRAB: Compensation Release Assessment at the Broad scale) was employed to design new compensation release regimes from the reservoir which account for the seasonal flow requirements of a number of key fish species. The impact of impoundment on the current flow regime was modelled and the impacts of predicted new regimes were predicted, using a 1D hydrodynamic model (HEC-RAS), as part of a modelling process known as CRAM (Compensation Release Assessment at the Meso-scale). Depth and velocity were the foci of the analysis as they are the two habitat requirements most well documented for the fish species in question, they could be modelled using HEC-RAS and they can act as surrogates for other habitat parameters such as temperature and substrate. The suitability of the depth and velocity combinations predicted using the HEC-RAS model were assessed using fuzzy-rule based modelling, which allowed the habitat quality of a given parameter combination to be quantified. Based on the results of the investigation it was concluded that there has

  19. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    Energy Technology Data Exchange (ETDEWEB)

    None

    1998-01-01

    Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations.

  20. Cloud computing and Reservoir project

    International Nuclear Information System (INIS)

    Beco, S.; Maraschini, A.; Pacini, F.; Biran, O.

    2009-01-01

    The support for complex services delivery is becoming a key point in current internet technology. Current trends in internet applications are characterized by on demand delivery of ever growing amounts of content. The future internet of services will have to deliver content intensive applications to users with quality of service and security guarantees. This paper describes the Reservoir project and the challenge of a reliable and effective delivery of services as utilities in a commercial scenario. It starts by analyzing the needs of a future infrastructure provider and introducing the key concept of a service oriented architecture that combines virtualisation-aware grid with grid-aware virtualisation, while being driven by business service management. This article will then focus on the benefits and the innovations derived from the Reservoir approach. Eventually, a high level view of Reservoir general architecture is illustrated.

  1. Using Chemicals to Optimize Conformance Control in Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Seright, Randall S.; Liang, Jenn-Tai; Schrader, Richard; Hagstrom II, John; Liu, Jin; Wavrik, Kathryn

    1999-09-27

    This report describes work performed during the first year of the project, ''Using Chemicals to Optimize Conformance Control in Fractured Reservoirs.'' This research project has three objectives. The first objective is to develop a capability to predict and optimize the ability of gels to reduce permeability to water more than that to oil or gas. The second objective is to develop procedures for optimizing blocking agent placement in wells where hydraulic fractures cause channeling problems. The third objective is to develop procedures to optimize blocking agent placement in naturally fractured reservoirs. This research project consists of three tasks, each of which addresses one of the above objectives. Our work is directed at both injection wells and production wells and at vertical, horizontal, and highly deviated wells.

  2. Reservoir effects in radiocarbon dating

    International Nuclear Information System (INIS)

    Head, M.J.

    1997-01-01

    Full text: The radiocarbon dating technique depends essentially on the assumption that atmospheric carbon dioxide containing the cosmogenic radioisotope 14 C enters into a state of equilibrium with all living material (plants and animals) as part of the terrestrial carbon cycle. Terrestrial reservoir effects occur when the atmospheric 14 C signal is diluted by local effects where systems depleted in 14 C mix with systems that are in equilibrium with the atmosphere. Naturally, this can occur with plant material growing close to an active volcano adding very old CO 2 to the atmosphere (the original 14 C has completely decayed). It can also occur in highly industrialised areas where fossil fuel derived CO 2 dilutes the atmospheric signal. A terrestrial reservoir effect can occur in the case of fresh water shells living in rivers or lakes where there is an input of ground water from springs or a raising of the water table. Soluble bicarbonate derived from the dissolution of very old limestone produces a 14 C dilution effect. Land snail shells and stream carbonate depositions (tufas and travertines) can be affected by a similar mechanism. Alternatively, in specific cases, these reservoir effects may not occur. This means that general interpretations assuming quantitative values for these terrestrial effects are not possible. Each microenvironment associated with samples being analysed needs to be evaluated independently. Similarly, the marine environment produces reservoir effects. With respect to marine shells and corals, the water depth at which carbonate growth occurs can significantly affect quantitative 14 C dilution, especially in areas where very old water is uplifted, mixing with top layers of water that undergo significant exchange with atmospheric CO 2 . Hence, generalisations with respect to the marine reservoir effect also pose problems. These can be exacerbated by the mixing of sea water with either terrestrial water in estuaries, or ground water where

  3. Sedimentological and Geomorphological Effects of Reservoir Flushing: The Cachi Reservoir, Costa Rica, 1996

    DEFF Research Database (Denmark)

    Brandt, Anders; Swenning, Joar

    1999-01-01

    Physical geography, hydrology, geomorphology, sediment transport, erosion, sedimentation, dams, reservoirs......Physical geography, hydrology, geomorphology, sediment transport, erosion, sedimentation, dams, reservoirs...

  4. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    Energy Technology Data Exchange (ETDEWEB)

    P. K. Pande

    1998-10-29

    Initial drilling of wells on a uniform spacing, without regard to reservoir performance and characterization, must become a process of the past. Such efforts do not optimize reservoir development as they fail to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. These reservoirs are typically characterized by: o Large, discontinuous pay intervals o Vertical and lateral changes in reservoir properties o Low reservoir energy o High residual oil saturation o Low recovery efficiency

  5. Ecologically-friendly operation scheme for the Jinping cascaded reservoirs in the Yalongjiang River, China

    Science.gov (United States)

    Chen, Duan; Chen, Qiuwen; Li, Ruonan; Blanckaert, Koen; Cai, Desuo

    2014-06-01

    Ecologically-friendly reservoir operation procedures aim to conserve key ecosystem properties in the rivers, while minimizing the sacrifice of socioeconomic interests. This study focused on the Jinping cascaded reservoirs as a case study. An optimization model was developed to explore a balance between the ecological flow requirement (EFR) of a target fish species ( Schizothorax chongi) in the dewatered natural channel section, and annual power production. The EFR for the channel was determined by the Tennant method and a fish habitat model, respectively. The optimization model was solved by using an adaptive real-coded genetic algorithm. Several operation scenarios corresponding to the ecological flow series were evaluated using the optimization model. Through comparisons, an optimal operational scheme, which combines relatively low power production loss with a preferred ecological flow regime in the dewatered channel, is proposed for the cascaded reservoirs. Under the recommended scheme, the discharge into the Dahewan river reach in the dry season ranges from 36 to 50 m3/s. This will enable at least 50% of the target fish habitats in the channel to be conserved, at a cost of only 2.5% annual power production loss. The study demonstrates that the use of EFRs is an efficient approach to the optimization of reservoir operation in an ecologically friendly way. Similar modeling, for other important fish species and ecosystem functions, supplemented by field validation of results, is needed in order to secure the long-term conservation of the affected river ecosystem.

  6. SIRIU RESERVOIR, BUZAU RIVER (ROMANIA

    Directory of Open Access Journals (Sweden)

    Daniel Constantin DIACONU

    2008-06-01

    Full Text Available Siriu reservoir, owes it`s creation to the dam built on the river Buzau, in the town which bears the same name. The reservoir has a hydro energetic role, to diminish the maximum flow and to provide water to the localities below. The partial exploitation of the lake, began in 1984; Since that time, the initial bed of the river began to accumulate large quantities of alluvia, reducing the retention capacity of the lake, which had a volume of 125 million m3. The changes produced are determined by many topographic surveys at the bottom of the lake.

  7. Dynamic Channel Allocation

    Science.gov (United States)

    2003-09-01

    21 9. Beowulf Ethernet Channel Bonding.................................................22 F. SUMMARY...on demand, hybrid channel allocation in wireless networks, and 3 Beowulf Ethernet channel bonding. The background information presented in this...channels are available for dynamic allocation [Ref 32]. 9. Beowulf Ethernet Channel Bonding A by-product of using older computers in a NASA research lab

  8. The Acoustic Wave Field Features and Thickness Analysis of the Footstone of the Yellow River Levee

    Science.gov (United States)

    Li, G.; Zhu, P.; Yang, K.; Jiang, J.

    2014-12-01

    The dangerous control engineering often stacks stones, named the footstone, outside the sediment matrix to resist the scour erosion in lower Yellow River. In order to ensure the stability of the bank, the footstones are stacked in the certain proportion. Due to the effect of the seasonal changes and the adjustment of the upstream reservoir, the water depth of the Yellow River near the lobes of banks changes constantly. The scouring erosion in flood season and depositing in dry season make the stacked footstones to be washed away. The thickness and the location of the maximum burial depth of the footstones are the important supporting data for calculating the river scour. Thus, it is significant to investigate the location, thickness and slope of the footstones. This study proposed a new method to distinguish the silt and footing stones according to their frequency differences by applying time-frequency analysis to the sub-bottom profiler data, and to estimate the thickness of the footstones by using the messy reflection waves formed by the riprap, and then to has solved the estimation of the maximum scour depth.

  9. Reservoir Sedimentation Based on Uncertainty Analysis

    Directory of Open Access Journals (Sweden)

    Farhad Imanshoar

    2014-01-01

    Full Text Available Reservoir sedimentation can result in loss of much needed reservoir storage capacity, reducing the useful life of dams. Thus, sufficient sediment storage capacity should be provided for the reservoir design stage to ensure that sediment accumulation will not impair the functioning of the reservoir during the useful operational-economic life of the project. However, an important issue to consider when estimating reservoir sedimentation and accumulation is the uncertainty involved in reservoir sedimentation. In this paper, the basic factors influencing the density of sediments deposited in reservoirs are discussed, and uncertainties in reservoir sedimentation have been determined using the Delta method. Further, Kenny Reservoir in the White River Basin in northwestern Colorado was selected to determine the density of deposits in the reservoir and the coefficient of variation. The results of this investigation have indicated that by using the Delta method in the case of Kenny Reservoir, the uncertainty regarding accumulated sediment density, expressed by the coefficient of variation for a period of 50 years of reservoir operation, could be reduced to about 10%. Results of the Delta method suggest an applicable approach for dead storage planning via interfacing with uncertainties associated with reservoir sedimentation.

  10. Reservoir monitoring and characterization for heavy-oil thermal recovery

    Energy Technology Data Exchange (ETDEWEB)

    Pankaj, P.; Pathak, V. [Indian School of Mines (India)

    2005-11-01

    Cyclic steam stimulation (CSS) techniques can become uneconomical in their later cycles, as the oil to steam ratio can drop significantly. Time-lapse seismic assisted follow-up programs can improve oil to steam ratios and production rates within 1 cycle. This study presented the results of an optimized quantitative cross-calibration and cross-training stream that was developed for time-lapse seismic data analysis using data normalization as a bridge. It was anticipated that the stream would provide more consistent results than independent training for reservoir monitoring. In order to compensate for the redundancy of conventional seismic attributes, seismic attributes calculated from principal component decomposition of the seismic data were developed and used for reservoir monitoring. Time-lapse data sets were analyzed by the merging of 2 data sets. Attributes were calculated separately from individual surveys. A significant improvement was noted on time lapse data analysis. Post-stack inversion was applied to time lapse data sets, as the time lapse data normalization was no longer required because the wavelets were extracted independently from each data set. Vertical conformance revealed that sequence architecture had a significant influence on steam migration. A sequence with a high mud content limited both the vertical and horizontal migration of the steam chamber. It was determined that the functional relation of P- to S- wave velocities played an important role in extracting S-wave information from pre-stack data. The mud-rock line established from in-situ P- and S- wave velocity measurements was optimized for Cold Lake clastic rocks. It was concluded that with an optimized mud-rock line and high frequency seismic data, reservoir heterogeneity can be well defined by fluid factor. When applied to reservoir monitoring, this method defined steam channels and successfully identified lithological barriers within the reservoir. 5 refs., 7 figs.

  11. Data assimilation in reservoir management

    NARCIS (Netherlands)

    Rommelse, J.R.

    2009-01-01

    The research presented in this thesis aims at improving computer models that allow simulations of water, oil and gas flows in subsurface petroleum reservoirs. This is done by integrating, or assimilating, measurements into physics-bases models. In recent years petroleum technology has developed

  12. Reservoirs in the United States

    Science.gov (United States)

    Harbeck, G. Earl

    1948-01-01

    Man has engaged in the control of flowing water since history began. Among his early recorded efforts were reservoirs for muncipal water-supplies constructed near ancient Jerusalem to store water which was brought there in masonry conduits. 1/  Irrigation was practiced in Egypt as early as 2000 B. C. There the "basin system" was used from ancient times until the 19th century. The land was divided , into basins of approximately 40,000 acres, separated by earthen dikes. 2/  Flood waters of the Nile generally inundated the basins through canals, many of which were built by the Pharaohs. Even then the economic consequences of a deficient annual flood were recognized. Lake Maeris, which according to Herodotus was an ancient storage reservoir, is said to have had an area of 30,000 acres. In India, the British found at the time of their occupancy of the Presidency of Madras about 50,000 reservoirs for irrigation, many believed to be of ancient construction. 3/ During the period 115-130 A. D. reservoirs were built to improve the water-supply of Athens. Much has been written concerning the elaborate collection and distribution system built to supply Rome, and parts of it remain to this day as monuments to the engineering skill employed by the Romans in solving the problem of large-scale municipal water-supplies.

  13. Reasons for reservoir effect variability

    DEFF Research Database (Denmark)

    Philippsen, Bente

    2013-01-01

    , aquatic plants and fish from the rivers Alster and Trave range between zero and about 3,000 radiocarbon years. The reservoir age of water DIC depends to a large extent on the origin of the water and is for example correlated with precipitation amounts. These short-term variations are smoothed out in water...

  14. The use of chemical tracers to water injection processes applied on Romanian reservoirs

    Directory of Open Access Journals (Sweden)

    Zecheru M.

    2013-05-01

    Full Text Available The hydrocarbon reservoirs are extremely complex, each reservoir having its own identity. Reservoirs heterogeneity (mainly regarding the layered ones frequently results in low recovery efficiencies, both under the primary regime and when different agents are injected from the surface. EOR processes efficiency depends on how detailed the reservoir is known and on the information related to fluids flow through reservoir. There are certain analyzes, investigations and tests providing good knowledge about the reservoir. The tracer tests are among them, being frequently used to water injection processes. Depending on the method used, IWTT (Interwell tracer test, SWTT (Single-Well Tracer Test, TWTT (Two-Well Tracer Test, information are obtained as related to: the setting of the preferential flow path of the injected fluid, the identification of water channels, evidencing the geological barriers, determining the residual oil saturation, around the well bore or along the tracer's path between two wells. This paper is focused on ICPT Câmpina efforts related to the use of the chemical tracers to the water injection processes applied to the oil reservoirs of Romania. It describes the usual tracers and the methods used to detect them in the reaction wells. Up to now, more than 50 tests with IWTT tracers have been performed on-site and this work presents some of their results.

  15. Using Chemicals to Optimize Conformance Control in Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Seright, Randall S.

    2000-09-20

    This research project has three objectives. The first objective is to develop a capability to predict and optimize the ability of gels to reduce permeability to water more than that to oil or gas. The second objective is to develop procedures for optimizing blocking agent placement in wells where hydraulic fractures cause channeling problems. The third objective is to develop procedures to optimize blocking agent placement in naturally fractured reservoirs. This research project consists of three tasks, each of which addresses one of the above objectives. This work is directed at both injection wells and production wells and at vertical, horizontal, and highly deviated wells.

  16. Sedimentary processes and architecture of Upper Cretaceous deep-sea channel deposits: a case from the Skole Nappe, Polish Outer Carpathians

    Science.gov (United States)

    Łapcik, Piotr

    2018-02-01

    Deep-sea channels are one of the architectonic elements, forming the main conduits for sand and gravel material in the turbidite depositional systems. Deep-sea channel facies are mostly represented by stacking of thick-bedded massive sandstones with abundant coarse-grained material, ripped-up clasts, amalgamation and large scale erosional structures. The Manasterz Quarry of the Ropianka Formation (Upper Cretaceous, Skole Nappe, Carpathians) contains a succession of at least 31 m of thick-bedded high-density turbidites alternated with clast-rich sandy debrites, which are interpreted as axial deposits of a deep-sea channel. The section studied includes 5 or 6 storeys with debrite basal lag deposits covered by amalgamated turbidite fills. The thickness of particular storeys varies from 2.5 to 13 m. Vertical stacking of similar facies through the whole thickness of the section suggest a hierarchically higher channel-fill or a channel complex set, with an aggradation rate higher than its lateral migration. Such channel axis facies cannot aggrade without simultaneous aggradation of levee confinement, which was distinguished in an associated section located to the NW from the Manasterz Quarry. Lateral offset of channel axis facies into channel margin or channel levee facies is estimated at less than 800 m. The Manasterz Quarry section represents mostly the filling and amalgamation stage of channel formation. The described channel architectural elements of the Ropianka Formation are located within the so-called Łańcut Channel Zone, which was previously thought to be Oligocene but may have been present already in the Late Cretaceous.

  17. Reservoir Cathode for Electric Space Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a reservoir cathode to improve performance in both ion and Hall-effect thrusters. We propose to adapt our existing reservoir cathode technology to this...

  18. 49 CFR 236.792 - Reservoir, equalizing.

    Science.gov (United States)

    2010-10-01

    ... Reservoir, equalizing. An air reservoir connected with and adding volume to the top portion of the equalizing piston chamber of the automatic brake valve, to provide uniform service reductions in brake pipe...

  19. Dissolved methane in Indian freshwater reservoirs

    Digital Repository Service at National Institute of Oceanography (India)

    Narvenkar, G.; Naqvi, S.W.A.; Kurian, S.; Shenoy, D.M.; Pratihary, A.K.; Naik, H.; Patil, S.; Sarkar, A.; Gauns, M.

    Emission of methane (CH4), a potent greenhouse gas, from tropical reservoirs is of interest because such reservoirs experience conducive conditions for CH4 production through anaerobic microbial activities. It has been suggested that Indian...

  20. The Methane Hydrate Reservoir System

    Science.gov (United States)

    Flemings, P. B.; Liu, X.

    2007-12-01

    We use multi phase flow modeling and field examples (Hydrate Ridge, offshore Oregon and Blake Ridge, offshore North Carolina) to demonstrate that the methane hydrate reservoir system links traditional and non- traditional hydrocarbon system components: free gas flow is a fundamental control on this system. As in a traditional hydrocarbon reservoir, gas migrates into the hydrate reservoir as a separate phase (secondary migration) where it is trapped in a gas column beneath the base of the hydrate layer. With sufficient gas supply, buoyancy forces exceed either the capillary entry pressure of the cap rock or the fracture strength of the cap rock, and gas leaks into the hydrate stability zone, or cap rock. When gas enters the hydrate stability zone and forms hydrate, it becomes a very non traditional reservoir. Free gas forms hydrate, depletes water, and elevates salinity until pore water is too saline for further hydrate formation: salinity and hydrate concentration increase upwards from the base of the regional hydrate stability zone (RHSZ) to the seafloor and the base of the hydrate stability zone has significant topography. Gas chimneys couple the free gas zone to the seafloor through high salinity conduits that are maintained at the three-phase boundary by gas flow. As a result, significant amounts of gaseous methane can bypass the RHSZ, which implies a significantly smaller hydrate reservoir than previously envisioned. Hydrate within gas chimneys lie at the three-phase boundary and thus small increases in temperature or decreases in pressure can immediately transport methane into the ocean. This type of hydrate deposit may be the most economical for producing energy because it has very high methane concentrations (Sh > 70%) located near the seafloor, which lie on the three-phase boundary.

  1. Lithofacies paleogeography mapping and reservoir prediction in tight sandstone strata: A case study from central Sichuan Basin, China

    Directory of Open Access Journals (Sweden)

    Yuan Zhong

    2017-09-01

    Full Text Available Sand-rich tight sandstone reservoirs are potential areas for oil and gas exploration. However, the high ratio of sandstone thickness to that of the strata in the formation poses many challenges and uncertainties to traditional lithofacies paleogeography mapping. Therefore, the prediction of reservoir sweet spots has remained problematic in the field of petroleum exploration. This study provides new insight into resolving this problem, based on the analyses of depositional characteristics of a typical modern sand-rich formation in a shallow braided river delta of the central Sichuan Basin, China. The varieties of sand-rich strata in the braided river delta environment include primary braided channels, secondary distributary channels and the distribution of sediments is controlled by the successive superposed strata deposited in paleogeomorphic valleys. The primary distributary channels have stronger hydrodynamic forces with higher proportions of coarse sand deposits than the secondary distributary channels. Therefore, lithofacies paleogeography mapping is controlled by the geomorphology, valley locations, and the migration of channels. We reconstructed the paleogeomorphology and valley systems that existed prior to the deposition of the Xujiahe Formation. Following this, rock-electro identification model for coarse skeletal sand bodies was constructed based on coring data. The results suggest that skeletal sand bodies in primary distributary channels occur mainly in the valleys and low-lying areas, whereas secondary distributary channels and fine deposits generally occur in the highland areas. The thickness distribution of skeletal sand bodies and lithofacies paleogeography map indicate a positive correlation in primary distributary channels and reservoir thickness. A significant correlation exists between different sedimentary facies and petrophysical properties. In addition, the degree of reservoir development in different sedimentary facies

  2. Reservoir characterization of the Snorre Field

    OpenAIRE

    Gjestvang, Jørgen

    2016-01-01

    Master's thesis in Petroleum engineering The fluvial sandstone in the Snorre field consists of braided to meander streams deposited in arid and in humid climate that show a clear differences in the sedimentology and reservoir properties, especially the silt content in large part of the reservoir which decrease the reservoir properties and water saturation. The heterogeneity of these fluvial formations combined with the faulting history makes this reservoir highly complex with many local an...

  3. Reservoir resistivity characterization incorporating flow dynamics

    KAUST Repository

    Arango, Santiago

    2016-04-07

    Systems and methods for reservoir resistivity characterization are provided, in various aspects, an integrated framework for the estimation of Archie\\'s parameters for a strongly heterogeneous reservoir utilizing the dynamics of the reservoir are provided. The framework can encompass a Bayesian estimation/inversion method for estimating the reservoir parameters, integrating production and time lapse formation conductivity data to achieve a better understanding of the subsurface rock conductivity properties and hence improve water saturation imaging.

  4. Morphology of the 1984 open-channel lava flow at Krafla volcano, northern Iceland

    Science.gov (United States)

    Rossi, Matti J.

    1997-09-01

    An open-channel lava flow of olivine tholeiite basalt, 9 km long and 1-2 km wide, formed in a volcanic eruption that took place in the Krafla volcano, Iceland, on the 4-18 September 1984. The eruption started with emplacement of a pahoehoe sheet which was fed by a 8.5-km-long fissure. After two days of eruption, lava effusion from the fissure ceased but one crater at the northern end of the fissure continued to release lava for another twelve days. That crater supplied an open-channel flow that moved toward the north along the rift valley. The lava was emplaced on a slope of 1°. The final lava flow is composed of five flow facies: (1) the initial pahoehoe sheet; (2) proximal slab pahoehoe and aa; (3) shelly-type overflows from the channel; (4) distal rubbly aa lava; and (5) secondary outbreaks of toothpaste lava and cauliflower aa. The main lava channel within the flow is 6.4 km long. The mean width of this channel is 189 m (103 m S.D.). An initial lava channel that forms in a Bingham plastic substance is fairly constant in width. This channel, however, varies in width especially in the proximal part indicating channel erosion. Large drifted blocks of channel walls are found throughout the flow front area and on the top of overflow levees. This suggests that the channel erosion was mainly mechanical. The lava flow has a mean height of 6 m above its surroundings, measured at the flow margins. However, a study of the pre-flow topography indicates that the lava filled a considerable topographic depression. Combined surface and pre-flow profiles give an average lava-flow thickness of 11 m; the thickness of the initial sheet-flow is estimated as 2 m. The volume of the lava flow calculated from these figures is 0.11 km 3. The mean effusion rate was 91 m 3/s. When lava flow models are used to deduce the rheological properties of this type of lava flow, the following points must be considered: (1) when a lava flow is emplaced along tectonic lineaments, its depth and

  5. Tenth workshop on geothermal reservoir engineering: proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-22

    The workshop contains presentations in the following areas: (1) reservoir engineering research; (2) field development; (3) vapor-dominated systems; (4) the Geysers thermal area; (5) well test analysis; (6) production engineering; (7) reservoir evaluation; (8) geochemistry and injection; (9) numerical simulation; and (10) reservoir physics. (ACR)

  6. 32 CFR 644.4 - Reservoir Projects.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Reservoir Projects. 644.4 Section 644.4 National... HANDBOOK Project Planning Civil Works § 644.4 Reservoir Projects. (a) Joint land acquisition policy for reservoir projects. The joint policies of the Department of the Interior and the Department of the Army...

  7. Amplitude various angles (AVA) phenomena in thin layer reservoir: Case study of various reservoirs

    International Nuclear Information System (INIS)

    thfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia))" data-affiliation=" (Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Basic Science Center A 4thfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia))" >Nurhandoko, Bagus Endar B.; Susilowati

    2015-01-01

    Amplitude various offset is widely used in petroleum exploration as well as in petroleum development field. Generally, phenomenon of amplitude in various angles assumes reservoir’s layer is quite thick. It also means that the wave is assumed as a very high frequency. But, in natural condition, the seismic wave is band limited and has quite low frequency. Therefore, topic about amplitude various angles in thin layer reservoir as well as low frequency assumption is important to be considered. Thin layer reservoir means the thickness of reservoir is about or less than quarter of wavelength. In this paper, I studied about the reflection phenomena in elastic wave which considering interference from thin layer reservoir and transmission wave. I applied Zoeppritz equation for modeling reflected wave of top reservoir, reflected wave of bottom reservoir, and also transmission elastic wave of reservoir. Results show that the phenomena of AVA in thin layer reservoir are frequency dependent. Thin layer reservoir causes interference between reflected wave of top reservoir and reflected wave of bottom reservoir. These phenomena are frequently neglected, however, in real practices. Even though, the impact of inattention in interference phenomena caused by thin layer in AVA may cause inaccurate reservoir characterization. The relation between classes of AVA reservoir and reservoir’s character are different when effect of ones in thin reservoir and ones in thick reservoir are compared. In this paper, I present some AVA phenomena including its cross plot in various thin reservoir types based on some rock physics data of Indonesia

  8. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, Roy; Clarke, Don; Walker, Scott; Phillips, Chris; Nguyen, John; Moos, Dan; Tagbor, Kwasi

    2001-08-07

    This project was intended to increase recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs, transferring technology so that it can be applied in other sections of the Wilmington field and by operators in other slope and basin reservoirs is a primary component of the project.

  9. Calibration of Seismic Attributes for Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Wayne D. Pennington

    2002-09-29

    The project, "Calibration of Seismic Attributes for Reservoir Characterization," is now complete. Our original proposed scope of work included detailed analysis of seismic and other data from two to three hydrocarbon fields; we have analyzed data from four fields at this level of detail, two additional fields with less detail, and one other 2D seismic line used for experimentation. We also included time-lapse seismic data with ocean-bottom cable recordings in addition to the originally proposed static field data. A large number of publications and presentations have resulted from this work, inlcuding several that are in final stages of preparation or printing; one of these is a chapter on "Reservoir Geophysics" for the new Petroleum Engineering Handbook from the Society of Petroleum Engineers. Major results from this project include a new approach to evaluating seismic attributes in time-lapse monitoring studies, evaluation of pitfalls in the use of point-based measurements and facies classifications, novel applications of inversion results, improved methods of tying seismic data to the wellbore, and a comparison of methods used to detect pressure compartments. Some of the data sets used are in the public domain, allowing other investigators to test our techniques or to improve upon them using the same data. From the public-domain Stratton data set we have demonstrated that an apparent correlation between attributes derived along 'phantom' horizons are artifacts of isopach changes; only if the interpreter understands that the interpretation is based on this correlation with bed thickening or thinning, can reliable interpretations of channel horizons and facies be made. From the public-domain Boonsville data set we developed techniques to use conventional seismic attributes, including seismic facies generated under various neural network procedures, to subdivide regional facies determined from logs into productive and non-productive subfacies, and we

  10. CALIBRATION OF SEISMIC ATTRIBUTES FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Wayne D. Pennington; Horacio Acevedo; Aaron Green; Joshua Haataja; Shawn Len; Anastasia Minaeva; Deyi Xie

    2002-10-01

    The project, ''Calibration of Seismic Attributes for Reservoir Calibration,'' is now complete. Our original proposed scope of work included detailed analysis of seismic and other data from two to three hydrocarbon fields; we have analyzed data from four fields at this level of detail, two additional fields with less detail, and one other 2D seismic line used for experimentation. We also included time-lapse seismic data with ocean-bottom cable recordings in addition to the originally proposed static field data. A large number of publications and presentations have resulted from this work, including several that are in final stages of preparation or printing; one of these is a chapter on ''Reservoir Geophysics'' for the new Petroleum Engineering Handbook from the Society of Petroleum Engineers. Major results from this project include a new approach to evaluating seismic attributes in time-lapse monitoring studies, evaluation of pitfalls in the use of point-based measurements and facies classifications, novel applications of inversion results, improved methods of tying seismic data to the wellbore, and a comparison of methods used to detect pressure compartments. Some of the data sets used are in the public domain, allowing other investigators to test our techniques or to improve upon them using the same data. From the public-domain Stratton data set we have demonstrated that an apparent correlation between attributes derived along ''phantom'' horizons are artifacts of isopach changes; only if the interpreter understands that the interpretation is based on this correlation with bed thickening or thinning, can reliable interpretations of channel horizons and facies be made. From the public-domain Boonsville data set we developed techniques to use conventional seismic attributes, including seismic facies generated under various neural network procedures, to subdivide regional facies determined from logs into

  11. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Wiggins, M.L.; Evans, R.D.; Brown, R.L.; Gupta, A.

    2001-03-28

    This report focuses on integrating geoscience and engineering data to develop a consistent characterization of the naturally fractured reservoirs. During this reporting period, effort was focused on relating seismic data to reservoir properties of naturally fractured reservoirs, scaling well log data to generate interwell descriptors of these reservoirs, enhancing and debugging a naturally fractured reservoir simulator, and developing a horizontal wellbore model for use in the simulator.

  12. 4. International reservoir characterization technical conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    This volume contains the Proceedings of the Fourth International Reservoir Characterization Technical Conference held March 2-4, 1997 in Houston, Texas. The theme for the conference was Advances in Reservoir Characterization for Effective Reservoir Management. On March 2, 1997, the DOE Class Workshop kicked off with tutorials by Dr. Steve Begg (BP Exploration) and Dr. Ganesh Thakur (Chevron). Tutorial presentations are not included in these Proceedings but may be available from the authors. The conference consisted of the following topics: data acquisition; reservoir modeling; scaling reservoir properties; and managing uncertainty. Selected papers have been processed separately for inclusion in the Energy Science and Technology database.

  13. Reservoir microseismicity at the Ekofisk Oil Field

    Energy Technology Data Exchange (ETDEWEB)

    Rutledge, J.T.; Fairbanks, T.D. [Nambe Geophysical, Inc., Santa Fe, NM (United States); Albright, J.N. [Los Alamos National Lab., NM (United States); Boade, R.R. [Phillips Petroleum Co., Bartlesville, OK (United States); Dangerfield, J.; Landa, G.H. [Phillips Petroleum Co., Tananger (Norway)

    1994-07-01

    A triaxial, downhole geophone was deployed within the Ekofisk oil reservoir for monitoring ambient microseismicity as a test to determine if microearthquake signals generated from discrete shear failure of the reservoir rock could be detected. The results of the test were positive. During 104 hours of monitoring, 572 discrete events were recorded which have been identified as shear-failure microearthquakes. Reservoir microseismicity was detected at large distances (1000 m) from the monitor borehole and at rates (> 5 events per hour) which may allow practical characterization of the reservoir rock and overburden deformation induced by reservoir pressure changes.

  14. Smart Waterflooding in Carbonate Reservoirs

    DEFF Research Database (Denmark)

    Zahid, Adeel

    During the last decade, smart waterflooding has been developed into an emerging EOR technology both for carbonate and sandstone reservoirs that does not require toxic or expensive chemicals. Although it is widely accepted that different salinity brines may increase the oil recovery for carbonate...... reservoirs, understanding of the mechanism of this increase is still developing. To understand this smart waterflooding process, an extensive research has been carried out covering a broad range of disciplines within surface chemistry, thermodynamics of crude oil and brine, as well as their behavior...... that a heavy oil (that with a large fraction of heavy components) exhibited viscosity reduction in contact with brine, while a light crude oil exhibited emulsion formation. Most of reported high salinity waterflooding studies were carried out with outcrop chalk core plugs, and by performing spontaneous...

  15. Production Optimization of Oil Reservoirs

    DEFF Research Database (Denmark)

    Völcker, Carsten

    With an increasing demand for oil and diculties in nding new major oil elds, research on methods to improve oil recovery from existing elds is more necessary now than ever. The subject of this thesis is to construct ecient numerical methods for simulation and optimization of oil recovery...... programming (SQP) with line-search and BFGS approximations of the Hessian, and the adjoint method for ecient computation of the gradients. We demonstrate that the application of NMPC for optimal control of smart-wells has the potential to increase the economic value of an oil reservoir....... with emphasis on optimal control of water ooding with the use of smartwell technology. We have implemented immiscible ow of water and oil in isothermal reservoirs with isotropic heterogenous permeability elds. We use the method of lines for solution of the partial differential equation (PDE) system that governs...

  16. Multilevel techniques for Reservoir Simulation

    DEFF Research Database (Denmark)

    Christensen, Max la Cour

    for both variational upscaling and the construction of linear solvers. In particular, it is found to be beneficial (or even necessary) to apply an AMGe based multigrid solver to solve the upscaled problems. It is found that the AMGe upscaling changes the spectral properties of the matrix, which renders...... is extended to include a hybrid strategy, where FAS is combined with Newton’s method to construct a multilevel nonlinear preconditioner. This method demonstrates high efficiency and robustness. Second, an improved IMPES formulated reservoir simulator is implemented using a novel variational upscaling approach...... based on element-based Algebraic Multigrid (AMGe). In particular, an advanced AMGe technique with guaranteed approximation properties is used to construct a coarse multilevel hierarchy of Raviart-Thomas and L2 spaces for the Galerkin coarsening of a mixed formulation of the reservoir simulation...

  17. Diversity and community structure of cyanobacteria and other microbes in recycling irrigation reservoirs.

    Directory of Open Access Journals (Sweden)

    Ping Kong

    Full Text Available Recycling irrigation reservoirs (RIRs are emerging aquatic environments of global significance to crop production, water conservation and environmental sustainability. This study characterized the diversity and population structure of cyanobacteria and other detected microbes in water samples from eight RIRs and one adjacent runoff-free stream at three ornamental crop nurseries in eastern (VA1 and VA3 and central (VA2 Virginia after cloning and sequencing the 16S rRNA gene targeting cyanobacteria and chloroplast of eukaryotic phytoplankton. VA1 and VA2 utilize a multi-reservoir recycling irrigation system with runoff channeled to a sedimentation reservoir which then overflows into transition and retention reservoirs where water was pumped for irrigation. VA3 has a single sedimentation reservoir which was also used for irrigation. A total of 208 operational taxonomic units (OTU were identified from clone libraries of the water samples. Among them, 53 OTUs (358 clones were cyanobacteria comprising at least 12 genera dominated by Synechococcus species; 59 OTUs (387 clones were eukaryotic phytoplankton including green algae and diatoms; and 96 were other bacteria (111 clones. Overall, cyanobacteria were dominant in sedimentation reservoirs, while eukaryotic phytoplankton and other bacteria were dominant in transition/retention reservoirs and the stream, respectively. These results are direct evidence demonstrating the negative impact of nutrient-rich horticultural runoff, if not contained, on natural water resources. They also help in understanding the dynamics of water quality in RIRs and have practical implications. Although both single- and multi-reservoir recycling irrigation systems reduce the environmental footprint of horticultural production, the former is expected to have more cyanobacterial blooming, and consequently water quality issues, than the latter. Thus, a multi-reservoir recycling irrigation system should be preferred where

  18. Diversity and community structure of cyanobacteria and other microbes in recycling irrigation reservoirs.

    Science.gov (United States)

    Kong, Ping; Richardson, Patricia; Hong, Chuanxue

    2017-01-01

    Recycling irrigation reservoirs (RIRs) are emerging aquatic environments of global significance to crop production, water conservation and environmental sustainability. This study characterized the diversity and population structure of cyanobacteria and other detected microbes in water samples from eight RIRs and one adjacent runoff-free stream at three ornamental crop nurseries in eastern (VA1 and VA3) and central (VA2) Virginia after cloning and sequencing the 16S rRNA gene targeting cyanobacteria and chloroplast of eukaryotic phytoplankton. VA1 and VA2 utilize a multi-reservoir recycling irrigation system with runoff channeled to a sedimentation reservoir which then overflows into transition and retention reservoirs where water was pumped for irrigation. VA3 has a single sedimentation reservoir which was also used for irrigation. A total of 208 operational taxonomic units (OTU) were identified from clone libraries of the water samples. Among them, 53 OTUs (358 clones) were cyanobacteria comprising at least 12 genera dominated by Synechococcus species; 59 OTUs (387 clones) were eukaryotic phytoplankton including green algae and diatoms; and 96 were other bacteria (111 clones). Overall, cyanobacteria were dominant in sedimentation reservoirs, while eukaryotic phytoplankton and other bacteria were dominant in transition/retention reservoirs and the stream, respectively. These results are direct evidence demonstrating the negative impact of nutrient-rich horticultural runoff, if not contained, on natural water resources. They also help in understanding the dynamics of water quality in RIRs and have practical implications. Although both single- and multi-reservoir recycling irrigation systems reduce the environmental footprint of horticultural production, the former is expected to have more cyanobacterial blooming, and consequently water quality issues, than the latter. Thus, a multi-reservoir recycling irrigation system should be preferred where feasible.

  19. MIKROMITSETY- MIGRANTS IN MINGECHEVIR RESERVOIR

    Directory of Open Access Journals (Sweden)

    M. A. Salmanov

    2017-01-01

    Full Text Available Aim. It is hardly possible to predict the continued stability of the watercourse ecosystems without the study of biological characteristics and composition of organisms inhabiting them. In the last 35-40 years, environmental conditions of the Mingachevir reservoir are determined by the stationary anthropogenic pressure. It was found that such components of plankton as algae, bacteria and fungi play a leading role in the transformation and migration of pollutants. The role of the three groups of organisms is very important in maintaining the water quality by elimination of pollutants. Among the organisms inhabiting the Mingachevir Reservoir, micromycetes have not yet been studied. Therefore, the study of the species composition and seasonal dynamics, peculiarities of their growth and development in the environment with the presence of some of the pollutants should be considered to date.Methods. In order to determine the role of micromycetes-migrants in the mineralization of organic substrates, as an active participant of self-purification process, we used water samples from the bottom sediments as well as decaying and skeletonized stalks of cane, reeds, algae, macrophytes, exuvia of insects and fish remains submerged in water.Findings. For the first time, we obtained the data on the quality and quantity of microscopic mycelial fungi in freshwater bodies on the example of the Mingachevir water reservoir; we also studied the possibilities for oxygenating the autochthonous organic matter of allochthonous origin with micromycetes-migrants.Conclusions. It was found that the seasonal development of micromycetes-migrants within the Mingachevir reservoir is characterized by an increase in the number of species in the summer and a gradual reduction in species diversity in the fall. 

  20. Characterization of petroleum reservoirs in the Eocene Green River Formation, Central Uinta Basin, Utah

    Science.gov (United States)

    Morgan, C.D.; Bereskin, S.R.

    2003-01-01

    The oil-productive Eocene Green River Formation in the central Uinta Basin of northeastern Utah is divided into five distinct intervals. In stratigraphically ascending order these are: 1) Uteland Butte, 2) Castle Peak, 3) Travis, 4) Monument Butte, and 5) Beluga. The reservoir in the Uteland Butte interval is mainly lacustrine limestone with rare bar sandstone beds, whereas the reservoirs in the other four intervals are mainly channel and lacustrine sandstone beds. The changing depositional environments of Paleocene-Eocene Lake Uinta controlled the characteristics of each interval and the reservoir rock contained within. The Uteland Butte consists of carbonate and rare, thin, shallow-lacustrine sandstone bars deposited during the initial rise of the lake. The Castle Peak interval was deposited during a time of numerous and rapid lake-level fluctuations, which developed a simple drainage pattern across the exposed shallow and gentle shelf with each fall and rise cycle. The Travis interval records a time of active tectonism that created a steeper slope and a pronounced shelf break where thick cut-and-fill valleys developed during lake-level falls and rises. The Monument Butte interval represents a return to a gentle, shallow shelf where channel deposits are stacked in a lowstand delta plain and amalgamated into the most extensive reservoir in the central Uinta Basin. The Beluga interval represents a time of major lake expansion with fewer, less pronounced lake-level falls, resulting in isolated single-storied channel and shallow-bar sandstone deposits.

  1. The role of reservoir characterization in the reservoir management process (as reflected in the Department of Energy`s reservoir management demonstration program)

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, M.L. [BDM-Petroleum Technologies, Bartlesville, OK (United States); Young, M.A.; Madden, M.P. [BDM-Oklahoma, Bartlesville, OK (United States)] [and others

    1997-08-01

    Optimum reservoir recovery and profitability result from guidance of reservoir practices provided by an effective reservoir management plan. Success in developing the best, most appropriate reservoir management plan requires knowledge and consideration of (1) the reservoir system including rocks, and rock-fluid interactions (i.e., a characterization of the reservoir) as well as wellbores and associated equipment and surface facilities; (2) the technologies available to describe, analyze, and exploit the reservoir; and (3) the business environment under which the plan will be developed and implemented. Reservoir characterization is the essential to gain needed knowledge of the reservoir for reservoir management plan building. Reservoir characterization efforts can be appropriately scaled by considering the reservoir management context under which the plan is being built. Reservoir management plans de-optimize with time as technology and the business environment change or as new reservoir information indicates the reservoir characterization models on which the current plan is based are inadequate. BDM-Oklahoma and the Department of Energy have implemented a program of reservoir management demonstrations to encourage operators with limited resources and experience to learn, implement, and disperse sound reservoir management techniques through cooperative research and development projects whose objectives are to develop reservoir management plans. In each of the three projects currently underway, careful attention to reservoir management context assures a reservoir characterization approach that is sufficient, but not in excess of what is necessary, to devise and implement an effective reservoir management plan.

  2. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  3. Reservoir Model Information System: REMIS

    Science.gov (United States)

    Lee, Sang Yun; Lee, Kwang-Wu; Rhee, Taehyun; Neumann, Ulrich

    2009-01-01

    We describe a novel data visualization framework named Reservoir Model Information System (REMIS) for the display of complex and multi-dimensional data sets in oil reservoirs. It is aimed at facilitating visual exploration and analysis of data sets as well as user collaboration in an easier way. Our framework consists of two main modules: the data access point module and the data visualization module. For the data access point module, the Phrase-Driven Grammar System (PDGS) is adopted for helping users facilitate the visualization of data. It integrates data source applications and external visualization tools and allows users to formulate data query and visualization descriptions by selecting graphical icons in a menu or on a map with step-by-step visual guidance. For the data visualization module, we implemented our first prototype of an interactive volume viewer named REMVR to classify and to visualize geo-spatial specific data sets. By combining PDGS and REMVR, REMIS assists users better in describing visualizations and exploring data so that they can easily find desired data and explore interesting or meaningful relationships including trends and exceptions in oil reservoir model data.

  4. The origin of Venusian channels: Modelling of thermal erosion by lava

    Science.gov (United States)

    Bussey, D. B. J.; Sorensen, S-A.; Guest, J. E.

    1993-01-01

    Magellan imagery has revealed that channels, apparently volcanic in origin, are abundant on the surface of Venus. There has been much debate about the origin of these channels. Are they the result of erosional (either thermal or mechanical) or constructional processes? A common characteristic of the simple sinuous channels is that they show evidence of erosion near their source and then become purely constructional, forming levees and in some cases roofing over completely. One method of showing that thermal erosion is capable of producing the type of channels seen is to use computer modeling incorporating the physical conditions on Venus and the physical characteristics of the different types of lava that may have been erupted. It is possible to calculate, relatively easily, two channel parameters. The first is the erosion rate, which combined with eruption duration, gives depth. The second is for how long after leaving the source the erupted lava will continue to be capable of thermal erosion before constructional processes dominate. Making assumptions about the rheology of the lava (e.g., assume it behaves as a Bingham plastic) along with the slope angle yields a flow velocity and therefore a distance over which thermal erosion will take place. Due to the resolution (both vertical and horizontal) of the Magellan altimetric data, the distance from the source that the channel is erosional can be much more accurately measured than the depth of the channel. This will remain the case until stereo imagery becomes available for large areas of the planet.

  5. Sediment budget for Rediu reservoir catchment, North-Eastern Romania

    Science.gov (United States)

    Todosi, Cristian; Niculita, Mihai

    2016-04-01

    Sediment budgets are a useful tool for geomorphologic analysis, catchment management and environmental assessment, despite the uncertainties related to their assessment. We present the sediment budget construction and validation for a small catchment of 9.5319 kmp (953.19 ha) situated in the North-Eastern part of Romania. The Rediu reservoir was built between 1986 and 1988, on Rediu valley, a left tributary of Bahlui river, north-west from Iasi city. The catchment of the reservoir has 6.5 km in length and 2.5 km in maximum width, the altitudes decreasing from 170 m in the northern part, to 52 m in the southern part. The valley is symmetric, the altitude of the hillslopes going between 200 m to 75 m in one km length, in the transversal section with the maximum width. The floodplain is narrow having between 20 m to 210 m (in the area of confluence with Breazu tributary). The mean slope of the catchment is 6.4 degree, the maximum slope being 24.6 degrees. The length of channels which show banks of up to 2 m is 19.98 km. The land is used predominantly as crops (58.1 %), 16.7 % being covered by pastures (from which over half are eroded), 11.5 % percent of the catchment being covered by planted forests, 9.2 % by rural constructions and roads, 2.9 % by hayfields, 1.5 % by lakes and 0.1 % by orchards. Beside the Rediu reservoir, there are three ponds (15 771, 1761 and 751 sqm) in the catchment. We considered the trap efficiency for the reservoir and the ponds to be 95%. Aerial images from 1963, 1978 , 1984, 2005, 2008, 2010, 2012 and 2014 were used to assess the state of geomorphological processes before and after the reservoir construction. After 1970 a gully system situated in Breazu tributary sub-catchment and several active landslides along the main valley left side were forested. Beside these processes, soil erosion and human impact by constructions are the main processes generating sediment in the study area. The sediment yields were quantified by estimating the

  6. Challenges of reservoir properties and production history matching in a CHOPS reservoir study

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Mahbub [Department of Geoscience, University of Calgary (Canada)

    2011-07-01

    In order to meet increasing world energy demand, wells have to be drilled within very thin reservoir beds. This paper, we present one of the solutions for optimizing the reservoir characterization. Reservoir characterization is the process between the discovery of a property and the reservoir management phase. Principal data for reservoir modeling are: 4D Seismic interpretation, wireline log interpretation, core analysis, and petrophysical analysis. Reservoir conditions, perforation and completion technology are the key issues to the production rate of cold production. Reservoir modeling intends to minimize the risk factor, maximize production, and help determine the location for infill drillings. Cold heavy oil production with sand (CHOPS) is a method for enhancing primary production from heavy oil reservoirs. Gravitational forces, natural fluid pressure gradients and foamy oil flow phenomena are the major driving forces of the CHOPS mechanism. Finally, Reservoir characterization allows better understanding of permeability and porosity prediction.

  7. Channel Evolution Following Avulsion: an Example from the Yellow River Delta

    Science.gov (United States)

    Zheng, S.

    2017-12-01

    Long-term field observation of morphological adjustments of rivers following avulsions is lacked when studying the evolution of avulsive channel on deltas. Avulsion at the Yellow River Delta (YRD) is frequent with average lifespan of channels of only about a decade. The Qing-shui-gou channel, the recent lobe on the YRD, provides a rare opportunity for investigating channel evolution following artificial avulsion. The reasons for its longer lifespan also needs investigation of the channel evolution. In this study, we comprehensively analyzed the geomorphic adjustment of the channel based on filed survey data during 1976-2014. The evolution of the channel was impacted by anthropogenic activities, including artificial avulsion at the downstream channel reaches in 1996, alteration of runoff and sediment load through Water and Sediment Regulation Scheme (WSRS), construction of levees and dikes. Analysis on channel geometry showed that avulsions in 1976 and in 1996 both caused short-term (1 2 years) erosion at the upstream channel reaches. Following the avulsion in 1976, massive aggradation occurred at the channel reaches at the downstream of the avulsion point. A single-thread channel gradually formed, widened and enlarged as channel bed under-cut on the deposition material. As delta extended seaward and the longitudinal slope decreased with time, aggradation occurred and an alluvial ridge formed. The ratio of lateral slope to the longitudinal slope (i.e. gradient advantage) and the relative super-elevation of the channel were calculated to estimate the possibility of avulsion at the channel in the late 1990. Results showed that the slope ratio was greater than 20 locally and super-elevation near its critical value for avulsion. The fact, that natural avulsion did not occurred despite of high values of gradient advantage and super elevation, may indicate that they are not sufficient conditions for avulsion at highly human-controlled rivers, where channel boundaries are

  8. New Channels, New Possibilities

    DEFF Research Database (Denmark)

    Pieterson, Willem; Ebbers, Wolfgang; Østergaard Madsen, Christian

    2017-01-01

    In this contribution we discuss the characteristics of what we call the fourth generation of public sector service channels: social robots. Based on a review of relevant literature we discuss their characteristics and place into multi-channel models of service delivery. We argue that social robots...... is not one homogenous type of channels, but rather breaks down in different (sub)types of channels, each with different characteristics and possibilities to supplement and/or replace existing channels. Given the variety of channels, we foresee challenges in incorporating these new channels in multi-channel...... models of service delivery. This is especially relevant given the current lack of evaluations of such models, the broad range of channels available, and their different stages of deployment at governments around the world. Nevertheless, social robots offer an potentially very relevant addition...

  9. Impact of Petrophysical Properties on Hydraulic Fracturing and Development in Tight Volcanic Gas Reservoirs

    Directory of Open Access Journals (Sweden)

    Yinghao Shen

    2017-01-01

    Full Text Available The volcanic reservoir is an important kind of unconventional reservoir. The aqueous phase trapping (APT appears because of fracturing fluids filtration. However, APT can be autoremoved for some wells after certain shut-in time. But there is significant distinction for different reservoirs. Experiments were performed to study the petrophysical properties of a volcanic reservoir and the spontaneous imbibition is monitored by nuclear magnetic resonance (NMR and pulse-decay permeability. Results showed that natural cracks appear in the samples as well as high irreducible water saturation. There is a quick decrease of rock permeability once the rock contacts water. The pores filled during spontaneous imbibition are mainly the nanopores from NMR spectra. Full understanding of the mineralogical effect and sample heterogeneity benefits the selection of segments to fracturing. The fast flow-back scheme is applicable in this reservoir to minimize the damage. Because lots of water imbibed into the nanopores, the main flow channels become larger, which are beneficial to the permeability recovery after flow-back of hydraulic fracturing. This is helpful in understanding the APT autoremoval after certain shut-in time. Also, Keeping the appropriate production differential pressure is very important in achieving the long term efficient development of volcanic gas reservoirs.

  10. Paleogeographic evolution of carbonate reservoirs: geological and geophysical analysis at the Albian Campos Basin, Brazil

    Science.gov (United States)

    Castillo Vincentelli, Maria Gabriela; Favoreto, Julia; Roemers-Oliveira, Eduardo

    2018-02-01

    An integrated geophysical and geological analysis of a carbonate reservoir can offer an effective method to better understand the paleogeographical evolution and distribution of a geological reservoir and non-reservoir facies. Therefore, we propose a better method for obtaining geological facies from geophysical facies, helping to characterize the permo-porous system of this kind of play. The goal is to determine the main geological phases from a specific hydrocarbon producer (Albian Campos Basin, Brazil). The applied method includes the use of a petrographic and qualitative description from the integrated reservoir with seismic interpretation of an attribute map (energy, root mean square, mean amplitude, maximum negative amplitude, etc), all calculated at the Albian level for each of the five identified phases. The studied carbonate reservoir is approximately 6 km long with a main direction of NE-SW, and it was sub-divided as follows (from bottom to top): (1) the first depositional sequence of the bank was composed mainly of packstone, indicating that the local structure adjacent to the main bank is protected from environmental conditions; (2) characterized by the presence of grainstone developed at the higher structure; (3) the main sequence of the peloidal packstone with mudstones oncoids; (4) corresponds to the oil production of carbonate reservoirs formed by oolitic grainstone deposited at the top of the carbonate bank; at this phase, rising sea levels formed channels that connected the open sea shelf with the restricted circulation shelf; and (5) mudstone and wackestone represent the system’s flooding phase.

  11. Entre armas leves e a regulamentação internacional: para que lado o Brasil dirige uma política pública?

    OpenAIRE

    Cristiano Armando Diniz Guerra Silvestre; Flávia de Ávila

    2016-01-01

    Resumo: O crescimento da atenção internacional acerca da temática relacionada a armas leves tem gerado várias ações que evidenciam esta preocupação no âmbito internacional. Diversas organizações multilaterais – como a ONU com seu Programa de Ação da ONU para Prevenir, Combater e Suprimir o Comércio Ilícito de Armas Pequenas e Armamentos Leves em Todos seus Aspectos – e não-governamentais – tendo a Caritas por exemplo, seguem registrando seu uso em diversas zonas de conflito do mundo. Entretan...

  12. Avaliação do desempenho estrutural em serviço de lajes treliçadas pré-moldadas de concretos com agregados leves

    OpenAIRE

    Oliveira,Anderson de; Garcia,Sergio Luis González; Cordeiro,Guilherme Chagas

    2011-01-01

    O concreto com agregado leve tem sido cada vez mais empregado em razão da reduzida massa específica, do elevado isolamento térmico e acústico e da melhoria na resistência estrutural a carregamentos cíclicos. Neste trabalho foram estudados concretos com agregados leves com resistência à compressão em torno de 20 MPa e seu desempenho estrutural em lajes treliçadas pré-moldadas. Utilizaram-se três diferentes concretos com valores de massa específica entre 1.200 e 1.600 kg/m³. Os concretos foram ...

  13. Programas psicosociales de intervención cognitiva en población con signos de deterioro cognitivo leve (DCL: Revisión de efectos y eficacia

    Directory of Open Access Journals (Sweden)

    Fátima González Palau

    2012-01-01

    Full Text Available Debido al incremento en el porcentaje de adultos mayores, así como de las enfermedades degenerativas, existe un creciente interés en la determinación de métodos psicosociales eficaces dirigidos a sujetos con Deterioro Cognitivo leve. Recientes estudios experimentales exponen efectos positivos de las intervenciones cognitivas dirigidas a esta población, tanto en métodos tradicionales y como en estrategias de intervención por medio de nuevas tecnologías. la presente revisión proporciona un análisis sistemático de la literatura existente en miras de valorar el efecto y los alcances de las intervenciones cognitivas no farmacológicas existentes en la actualidad, dirigidas a adultos mayores con Deterioro Cognitivo leve.

  14. As categorias aspectuais e a formação de construções com o Verbo leve dar

    Directory of Open Access Journals (Sweden)

    Ana Paula Scher

    2005-11-01

    Full Text Available Este trabalho revela que, embora bastante produtiva, a ocorrência de sentenças com a forma "dar uma Xada em Y", no português do Brasil, depende de algumas restrições semânticas bastante sistemáticas. Através da observação de um conjunto de dados baseados na intuição de vários falantes do português brasileiro, descreve-se, em termos dos traços temporais que compõem as categorias aspectuais, a interpretação semântica que se pode atribuir a sentenças como essas, em que uma nominalização em -ada ocorre associada ao verbo leve dar. Ao final, sugere-se que a formação de tais sentenças depende da presença ou não de alguns dos traços temporais intrínsecos às eventualidades denotadas pelos predicados dos quais derivam.

  15. As categorias aspectuais e a formação de construções com o Verbo leve dar

    Directory of Open Access Journals (Sweden)

    Ana Paula Scher

    2013-11-01

    Full Text Available Este trabalho revela que, embora bastante produtiva, a ocorrência de sentenças com a forma "dar uma Xada em Y", no português do Brasil, depende de algumas restrições semânticas bastante sistemáticas. Através da observação de um conjunto de dados baseados na intuição de vários falantes do português brasileiro, descreve-se, em termos dos traços temporais que compõem as categorias aspectuais, a interpretação semântica que se pode atribuir a sentenças como essas, em que uma nominalização em -ada ocorre associada ao verbo leve dar. Ao final, sugere-se que a formação de tais sentenças depende da presença ou não de alguns dos traços temporais intrínsecos às eventualidades denotadas pelos predicados dos quais derivam.

  16. CAMBIOS EN LA EXPRESIÓN DE LOS MARCADORES DE DISFUNCIÓN ENDOTELIAL PAL-1/PAI-2 EN PREECLAMPSIA LEVE Y SEVERA, Y EN GESTANTES NORMOTENSAS SANAS

    Directory of Open Access Journals (Sweden)

    Rodrigo Valenzuela Grau

    2012-01-01

    Full Text Available Objetivo: Determinar las concentraciones del Inhibidor del Activador del Plasminógeno tipo 1 y 2(PAI 1 y 2 y del factor de crecimiento placentario (PIGF como marcadores de disfunción endotelial y angiogénesis en preeclampsia(PE leve y severa, respectivamente. Métodos: Estudio de casos y controles realizado en el Hospital Clínico de la Universidad de Chile durante junio del 2009 y diciembre del 2010. La población estuvo conformada por embarazadas adscritas durante el periodo de estudio y fue dividida en tres grupos: controles (n= 18, PE leve (n=9, PE severa (n=23. Se determinaron las concentraciones de PIGF y PAI-1/PAI-2 mediante técnicas de inmunoensayo a partir de las muestras obtenidas de cada paciente. Para el análisis estadístico se utilizó test de ANOVA-Bonferroni. Se consideró significativo un p < 0.05. Resultados: Se observó niveles menores de PlGF y mayores de PAI-1/PAI-2 en PE en comparación con los controles. Mujeres con PE severa mostraron niveles más altos de relación PAI-1/PAI-2 que mujeres con PE leve (p < 0.05. No hubo diferencia significativa para PlGF entre PE leve y severa. Conclusiones: La gravedad de la preeclampsia podría reflejarse en alteraciones de los biomarcadores de disfunción endotelial y angiogénesis. La medición de PlGF y relación PAI-1/PAI-2 en embarazos tempranos podría tener un valor pronóstico en el desarrollo de PE.

  17. Evaluación de la conducta vocacional de estudiantes con discapacidad intelectual leve en etapa de transición escuela-empleo

    OpenAIRE

    Labrín Díaz, Paula

    2015-01-01

    El objetivo de este trabajo es la construcción de instrumentos (inexistentes) que permitan evaluar los indicadores de la conducta vocacional en estudiantes con discapacidad intelectual leve que asisten al nivel laboral en centros de educación especial chilenos. Los indicadores que se consideran, acordes con los planteamientos de Rivas , son los siguientes : Historial personal, intereses vocacionales, factores de personalidad , habilidades y destrezas y estilos de aprendizaje. Los par...

  18. The fish fauna of Brokopondo Reservoir, Suriname, during 40 years of impoundment

    Directory of Open Access Journals (Sweden)

    Jan H. Mol

    Full Text Available We investigated long-term changes in the fish fauna of Brokopondo Reservoir, Suriname, the first large reservoir (1560 km² that was created in tropical rainforest. Before closure of the dam in 1964, the fish fauna of Suriname River had 172 species, high diversity and high evenness. The riverine fauna was dominated by small-sized species, but no single species was dominant in numbers. Large catfishes were dominant in biomass. Species were evenly distributed over riverine habitats: rapids, tributaries and main channel. Four years after closure of the dam, only 62 fish species were collected from Brokopondo Reservoir, but the composition of the fish fauna was still changing. The reservoir fauna in 1978 was very similar to the reservoir fauna in 2005, indicating that a stable equilibrium had been reached 14 years after closure of the dam. The reservoir fauna had 41 species, low diversity and low evenness. Most species of Suriname River and its tributaries with strict habitat requirements did not survive in Brokopondo Reservoir. Fish community structure was different among four habitats of Brokopondo Reservoir. The open-water habitat (10 species was dominated by the piscivores Serrasalmus rhombeus, Acestrorhynchus microlepis and Cichla ocellaris and their prey Bryconops melanurus and two Hemiodus species. B. melanurus fed on zooplankton, Culicinae pupae and terrestrial invertebrates. Hemiodus fed on fine flocculent detritus, demonstrating that the detritus-based food chain was still important in late stages of reservoir development. Serrasalmus rhombeus also fed on peccaries that drowned when swimming across the large reservoir in rough weather. The shore community (27 species was dominated by seven cichlids, but early stages and juveniles of the open-water species S. rhombeus and B. melanurus also occurred in the shore habitat. Fish biomass in the shore habitat was 66.5±59.9 kg ha-1. The cichlid Geophagus surinamensis and the characid B. melanurus

  19. Are Geotehrmal Reservoirs Stressed Out?

    Science.gov (United States)

    Davatzes, N. C.; Laboso, R. C.; Layland-Bachmann, C. E.; Feigl, K. L.; Foxall, W.; Tabrez, A. R.; Mellors, R. J.; Templeton, D. C.; Akerley, J.

    2017-12-01

    Crustal permeability can be strongly influenced by developing connected networks of open fractures. However, the detailed evolution of a fracture network, its extent, and the persistence of fracture porosity are difficult to analyze. Even in fault-hosted geothermal systems, where heat is brought to the surface from depth along a fault, hydrothermal flow is heterogeneously distributed. This is presumably due to variations in fracture density, connectivity, and attitude, as well as variations in fracture permeability caused by sealing of fractures by precipitated cements or compaction. At the Brady Geothermal field in Nevada, we test the relationship between the modeled local stress state perturbed by dislocations representing fault slip or volume changes in the geothermal reservoir inferred from surface deformation measured by InSAR and the location of successful geothermal wells, hydrothermal activity, and seismicity. We postulate that permeability is favored in volumes that experience positive Coulomb stress changes and reduced compression, which together promote high densities of dilatant fractures. Conversely, permeability can be inhibited in locations where Coulomb stress is reduced, compression promotes compaction, or where the faults are poorly oriented in the stress field and consequently slip infrequently. Over geologic time scales spanning the development of the fault system, these local stress states are strongly influenced by the geometry of the fault network relative to the remote stress driving slip. At shorter time scales, changes in fluid pressure within the fracture network constituting the reservoir cause elastic dilations and contractions. We integrate: (1) direct observations of stress state and fractures in boreholes and the mapped geometry of the fault network; (2) evidence of permeability from surface hydrothermal features, production/injection wells and surface deformations related to pumping history; and (3) seismicity to test the

  20. Nonlinear Multigrid for Reservoir Simulation

    DEFF Research Database (Denmark)

    Christensen, Max la Cour; Eskildsen, Klaus Langgren; Engsig-Karup, Allan Peter

    2016-01-01

    modeled after local linearization, leading to a nonlinear multigrid method in the form of the full-approximation scheme (FAS). It is demonstrated through numerical experiments that, without loss of robustness, the FAS method can outperform the conventional techniques in terms of algorithmic and numerical...... efficiency for a black-oil model. Furthermore, the use of the FAS method enables a significant reduction in memory usage compared with conventional techniques, which suggests new possibilities for improved large-scale reservoir simulation and numerical efficiency. Last, nonlinear multilevel preconditioning...

  1. A reservoir trap for antiprotons

    CERN Document Server

    Smorra, Christian; Franke, Kurt; Nagahama, Hiroki; Schneider, Georg; Higuchi, Takashi; Van Gorp, Simon; Blaum, Klaus; Matsuda, Yasuyuki; Quint, Wolfgang; Walz, Jochen; Yamazaki, Yasunori; Ulmer, Stefan

    2015-01-01

    We have developed techniques to extract arbitrary fractions of antiprotons from an accumulated reservoir, and to inject them into a Penning-trap system for high-precision measurements. In our trap-system antiproton storage times > 1.08 years are estimated. The device is fail-safe against power-cuts of up to 10 hours. This makes our planned comparisons of the fundamental properties of protons and antiprotons independent from accelerator cycles, and will enable us to perform experiments during long accelerator shutdown periods when background magnetic noise is low. The demonstrated scheme has the potential to be applied in many other precision Penning trap experiments dealing with exotic particles.

  2. Avaliação do desempenho estrutural em serviço de lajes treliçadas pré-moldadas de concretos com agregados leves

    Directory of Open Access Journals (Sweden)

    Anderson de Oliveira

    Full Text Available O concreto com agregado leve tem sido cada vez mais empregado em razão da reduzida massa específica, do elevado isolamento térmico e acústico e da melhoria na resistência estrutural a carregamentos cíclicos. Neste trabalho foram estudados concretos com agregados leves com resistência à compressão em torno de 20 MPa e seu desempenho estrutural em lajes treliçadas pré-moldadas. Utilizaram-se três diferentes concretos com valores de massa específica entre 1.200 e 1.600 kg/m³. Os concretos foram avaliados com relação à resistência à compressão (aos 3, 7 e 28 dias e à absorção total de água (aos 28 dias. Com os três tipos de concreto foram produzidas e ensaiadas à flexão lajes pré-moldadas (duas lajes para cada tipo de concreto, com a avaliação de seu comportamento no estado limite de serviço (ELS para cargas de curta duração, ou seja, sem considerar efeitos ao longo do tempo. Os resultados mostraram o potencial do uso de concretos com agregados leves nesse tipo de laje estrutural.

  3. Efeito do metacaulim nas propriedades do concreto leve estrutural - DOI: 10.4025/actascitechnol.v29i1.87

    Directory of Open Access Journals (Sweden)

    João Adriano Rossignolo

    2007-12-01

    Full Text Available Este trabalho apresenta os resultados da avaliação das modificações promovidas pelo Metacaulim no desempenho das propriedades do concreto com agregados leves. Foi analisado o efeito do Metacaulim na resistência à compressão, na resistência à tração por compressão diametral, no módulo de deformação, na absorção de água por imersão e na carbonatação do concreto com agregados leves. Nos resultados obtidos verificou-se que a adição de Metacaulim melhorou significativamente o desempenho da resistência à compressão, da resistência à tração por compressão diametral e da absorção de água por imersão e da carbonatação dos concretos leves.

  4. A Case Study of Preliminary Cost-Benefit Analysis of Building Levees to Mitigate the Joint Effects of Sea Level Rise and Storm Surge

    Directory of Open Access Journals (Sweden)

    Binbin Peng

    2018-02-01

    Full Text Available Sea-level rise (SLR will magnify the impacts of storm surge; the resulting severe flooding and inundation can cause huge damage to coastal communities. Community leaders are considering implementing adaptation strategies, typically hard engineering projects, to protect coastal assets and resources. It is important to understand the costs and benefits of the proposed project before any decision is made. To mitigate the flooding impact of joint effects of storm surge and SLR, building levee segments is chosen to be a corresponding adaptation strategy to protect the real estate assets in the study area—the City of Miami, FL, USA. This paper uses the classic Cost-Benefit Analysis (CBA to assess the cost efficiency and proposes corresponding improvements in the benefit estimation, by estimating the avoided damages of implementing levee projects. Results show that the city will benefit from implementing levee projects along the Miami River in both a one-time 10 year storm event with SLR and cumulative long-term damage scenarios. This study also suggests that conducting CBA is a critical process before making coastal adaptation planning investment. A more meaningful result of cost effectiveness is estimated by accounting for the appreciation and time value. In addition, a sensitivity analysis is conducted to verify how the choice of discount rate influences the result. Uncertain factors including the rate of SLR, storm intensification, land use changes, and real estate appreciation are further analyzed.

  5. Hadamard quantum broadcast channels

    Science.gov (United States)

    Wang, Qingle; Das, Siddhartha; Wilde, Mark M.

    2017-10-01

    We consider three different communication tasks for quantum broadcast channels, and we determine the capacity region of a Hadamard broadcast channel for these various tasks. We define a Hadamard broadcast channel to be such that the channel from the sender to one of the receivers is entanglement-breaking and the channel from the sender to the other receiver is complementary to this one. As such, this channel is a quantum generalization of a degraded broadcast channel, which is well known in classical information theory. The first communication task we consider is classical communication to both receivers, the second is quantum communication to the stronger receiver and classical communication to other, and the third is entanglement-assisted classical communication to the stronger receiver and unassisted classical communication to the other. The structure of a Hadamard broadcast channel plays a critical role in our analysis: The channel to the weaker receiver can be simulated by performing a measurement channel on the stronger receiver's system, followed by a preparation channel. As such, we can incorporate the classical output of the measurement channel as an auxiliary variable and solve all three of the above capacities for Hadamard broadcast channels, in this way avoiding known difficulties associated with quantum auxiliary variables.

  6. Effect of reservoir heterogeneity on air injection performance in a light oil reservoir

    Directory of Open Access Journals (Sweden)

    Hu Jia

    2018-03-01

    Full Text Available Air injection is a good option to development light oil reservoir. As well-known that, reservoir heterogeneity has great effect for various EOR processes. This also applies to air injection. However, oil recovery mechanisms and physical processes for air injection in heterogeneous reservoir with dip angle are still not well understood. The reported setting of reservoir heterogeneous for physical model or simulation model of air injection only simply uses different-layer permeability of porous media. In practice, reservoir heterogeneity follows the principle of geostatistics. How much of contrast in permeability actually challenges the air injection in light oil reservoir? This should be investigated by using layered porous medial settings of the classical Dykstra-Parsons style. Unfortunately, there has been no work addressing this issue for air injection in light oil reservoir. In this paper, Reservoir heterogeneity is quantified based on the use of different reservoir permeability distribution according to classical Dykstra-Parsons coefficients method. The aim of this work is to investigate the effect of reservoir heterogeneity on physical process and production performance of air injection in light oil reservoir through numerical reservoir simulation approach. The basic model is calibrated based on previous study. Total eleven pseudo compounders are included in this model and ten complexity of reactions are proposed to achieve the reaction scheme. Results show that oil recovery factor is decreased with the increasing of reservoir heterogeneity both for air and N2 injection from updip location, which is against the working behavior of air injection from updip location. Reservoir heterogeneity sometimes can act as positive effect to improve sweep efficiency as well as enhance production performance for air injection. High O2 content air injection can benefit oil recovery factor, also lead to early O2 breakthrough in heterogeneous reservoir. Well

  7. Data Compression of Hydrocarbon Reservoir Simulation Grids

    KAUST Repository

    Chavez, Gustavo Ivan

    2015-05-28

    A dense volumetric grid coming from an oil/gas reservoir simulation output is translated into a compact representation that supports desired features such as interactive visualization, geometric continuity, color mapping and quad representation. A set of four control curves per layer results from processing the grid data, and a complete set of these 3-dimensional surfaces represents the complete volume data and can map reservoir properties of interest to analysts. The processing results yield a representation of reservoir simulation results which has reduced data storage requirements and permits quick performance interaction between reservoir analysts and the simulation data. The degree of reservoir grid compression can be selected according to the quality required, by adjusting for different thresholds, such as approximation error and level of detail. The processions results are of potential benefit in applications such as interactive rendering, data compression, and in-situ visualization of large-scale oil/gas reservoir simulations.

  8. Sedimentological reservoir characteristics of the Paleocene fluvial/lacustrine Yabus Sandstone, Melut Basin, Sudan

    Science.gov (United States)

    Mahgoub, M. I.; Padmanabhan, E.; Abdullatif, O. M.

    2016-11-01

    Melut Basin in Sudan is regionally linked to the Mesozoic-Cenozoic Central and Western African Rift System (CWARS). The Paleocene Yabus Formation is the main oil producing reservoir in the basin. It is dominated by channel sandstone and shales deposited in fluvial/lacustrine environment during the third phase of rifting in the basin. Different scales of sedimentological heterogeneities influenced reservoir quality and architecture. The cores and well logs analyses revealed seven lithofacies representing fluvial, deltaic and lacustrine depositional environments. The sandstone is medium to coarse-grained, poorly to moderately-sorted and sub-angular to sub-rounded, arkosic-subarkosic to sublitharenite. On the basin scale, the Yabus Formation showed variation in sandstone bodies, thickness, geometry and architecture. On macro-scale, reservoir quality varies vertically and laterally within Yabus Sandstone where it shows progressive fining upward tendencies with different degrees of connectivity. The lower part of the reservoir showed well-connected and amalgamated sandstone bodies, the middle to the upper parts, however, have moderate to low sandstone bodies' connectivity and amalgamation. On micro-scale, sandstone reservoir quality is directly affected by textures and diagenetic changes such as compaction, cementation, alteration, dissolution and kaolinite clays pore fill and coat all have significantly reduced the reservoir porosity and permeability. The estimated porosity in Yabus Formation ranges from 2 to 20% with an average of 12%; while permeability varies from 200 to 500 mD and up to 1 Darcy. The understanding of different scales of sedimentological reservoir heterogeneities might contribute to better reservoir quality prediction, architecture, consequently enhancing development and productivity.

  9. Calcium Channel Blockers

    Science.gov (United States)

    ... conditions, such as Raynaud's disease For people of African heritage and older people, calcium channel blockers might ... high-blood-pressure/in-depth/calcium-channel-blockers/ART-20047605 . Mayo Clinic Footer Legal Conditions and Terms ...

  10. The importance of sand in the formation of avulsion channels within experimental fans that develop from sediment mixtures of mud and sand

    Science.gov (United States)

    Iscen, N.; Strom, K.

    2017-12-01

    Autogenic channel migration and avulsion has long been recognized as important drivers of alluvial fan dynamics. In the literature, several field studies have documented that the presence and the amount of sand transport through a channel is important for channel incision in alluvial fans and deltas. In our experiments, we present the general autogenic avulsion cycle of experimental alluvial fans with mixtures of cohesive sediment and sand with a range of boundary conditions, and we detail the importance of mobile sand fraction in the development of channels that lead to avulsion. Experimental observations demonstrate that new channels form at topographically low regions within the floodplain providing that sand is transported to these topographic lows due to overbank flow or levee breaching. In addition to the sediment transported from upstream, erosion of a previous deposit and an ongoing backfilling nearby are observed as the possible sources of sand getting into the ghost channels. We explore whether the presence of sand is important for channel development because it increases abrasion of the channel or because it changes the roughness characteristics of the flow. We also examine the affect of sediment and water supply change on the newly described channelization process and link distinctive channel morphologies to different stages of described channel development and the avulsion process.

  11. Development of gas and gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    In the study of gas reservoir development, the first year topics are restricted on reservoir characterization. There are two types of reservoir characterization. One is the reservoir formation characterization and the other is the reservoir fluid characterization. For the reservoir formation characterization, calculation of conditional simulation was compared with that of unconditional simulation. The results of conditional simulation has higher confidence level than the unconditional simulation because conditional simulation considers the sample location as well as distance correlation. In the reservoir fluid characterization, phase behavior calculations revealed that the component grouping is more important than the increase of number of components. From the liquid volume fraction with pressure drop, the phase behavior of reservoir fluid can be estimated. The calculation results of fluid recombination, constant composition expansion, and constant volume depletion are matched very well with the experimental data. In swelling test of the reservoir fluid with lean gas, the accuracy of dew point pressure forecast depends on the component characterization. (author). 28 figs., 10 tabs.

  12. Stretch due to Penile Prosthesis Reservoir Migration

    Directory of Open Access Journals (Sweden)

    E. Baten

    2016-03-01

    Full Text Available A 43-year old patient presented to the emergency department with stretch, due to impossible deflation of the penile prosthesis, 4 years after successful implant. A CT-scan showed migration of the reservoir to the left rectus abdominis muscle. Refilling of the reservoir was inhibited by muscular compression, causing stretch. Removal and replacement of the reservoir was performed, after which the prosthesis was well-functioning again. Migration of the penile prosthesis reservoir is extremely rare but can cause several complications, such as stretch.

  13. Global Reservoir and Dam Database, Version 1 (GRanDv1): Reservoirs, Revision 01

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Reservoir and Dam (GRanD) Database, Version 1.1 contains 6,862 records of reservoirs and their associated dams with a cumulative storage capacity of 6,197...

  14. KV7 potassium channels

    DEFF Research Database (Denmark)

    Stott, Jennifer B; Jepps, Thomas Andrew; Greenwood, Iain A

    2014-01-01

    Potassium channels are key regulators of smooth muscle tone, with increases in activity resulting in hyperpolarisation of the cell membrane, which acts to oppose vasoconstriction. Several potassium channels exist within smooth muscle, but the KV7 family of voltage-gated potassium channels have been...

  15. Quantum Channels With Memory

    International Nuclear Information System (INIS)

    Rybar, T.

    2012-01-01

    Quantum memory channels represent a very general, yet simple and comprehensible model for causal processes. As such they have attracted considerable research interest, mostly aimed on their transfer capabilities and structure properties. Most notably it was shown that memory channels can be implemented via physically naturally motivated collision models. We also define the concept of repeatable channels and show that only unital channels can be implemented repeat ably with pure memory channels. In the special case of qubit channels we also show that every unital qubit channel has a repeatable implementation. We also briefly explore the possibilities of stroboscopical simulation of channels and show that all random unitary channels can be stroboscopically simulated. Particularly in qubit case, all indivisible qubit channels are also random unitary, hence for qubit all indivisible channels can be stroboscopically simulated. Memory channels also naturally capture the framework of correlated experiments. We develop methods to gather and interpret data obtained in such setting and in detail examine the two qubit case. We also show that for control unitary interactions the measured data will never contradict a simple unitary evolution. Thus no memory effects can be spotted then. (author)

  16. Channel morphology [Chapter 5

    Science.gov (United States)

    Jonathan W. Long; Alvin L. Medina; Daniel G. Neary

    2012-01-01

    Channel morphology has become an increasingly important subject for analyzing the health of rivers and associated fish populations, particularly since the popularization of channel classification and assessment methods. Morphological data can help to evaluate the flows of sediment and water that influence aquatic and riparian habitat. Channel classification systems,...

  17. Estimation of Bank Erosion Due To Reservoir Operation in Cascade (Case Study: Citarum Cascade Reservoir

    Directory of Open Access Journals (Sweden)

    Sri Legowo

    2009-11-01

    Full Text Available Sedimentation is such a crucial issue to be noted once the accumulated sediment begins to fill the reservoir dead storage, this will then influence the long-term reservoir operation. The sediment accumulated requires a serious attention for it may influence the storage capacity and other reservoir management of activities. The continuous inflow of sediment to the reservoir will decrease the capacity of reservoir storage, the reservoir value in use, and the useful age of reservoir. Because of that, the rate of the sediment needs to be delayed as possible. In this research, the delay of the sediment rate is considered based on the rate of flow of landslide of the reservoir slope. The rate of flow of the sliding slope can be minimized by way of each reservoir autonomous efforts. This effort can be performed through; the regulation of fluctuating rate of reservoir surface current that does not cause suddenly drawdown and upraising as well. The research model is compiled using the searching technique of Non Linear Programming (NLP.The rate of bank erosion for the reservoir variates from 0.0009 to 0.0048 MCM/year, which is no sigrificant value to threaten the life time of reservoir.Mean while the rate of watershed sediment has a significant value, i.e: 3,02 MCM/year for Saguling that causes to fullfill the storage capacity in 40 next years (from years 2008.

  18. Multiobjective reservoir operating rules based on cascade reservoir input variable selection method

    Science.gov (United States)

    Yang, Guang; Guo, Shenglian; Liu, Pan; Li, Liping; Xu, Chongyu

    2017-04-01

    The input variable selection in multiobjective cascade reservoir operation is an important and difficult task. To address this problem, this study proposes the cascade reservoir input variable selection (CIS) method that searches for the most valuable input variables for decision making in multiple-objectivity cascade reservoir operations. From a case study of Hanjiang cascade reservoirs in China, we derive reservoir operating rules based on the combination of CIS and Gaussian radial basis functions (RBFs) methods and optimize the rules through Pareto-archived dynamically dimensioned search (PA-DDS) with two objectives: to maximize both power generation and water supply. We select the most effective input variables and evaluate their impacts on cascade reservoir operations. From the simulated trajectories of reservoir water level, power generation, and water supply, we analyze the multiobjective operating rules with several input variables. The results demonstrate that the CIS method performs well in the selection of input variables for the cascade reservoir operation, and the RBFs method can fully express the nonlinear operating rules for cascade reservoirs. We conclude that the CIS method is an effective and stable approach to identifying the most valuable information from a large number of candidate input variables. While the reservoir storage state is the most valuable information for the Hanjiang cascade reservoir multiobjective operation, the reservoir inflow is the most effective input variable for the single-objective operation of Danjiangkou.

  19. Impact of Reservoir Operation to the Inflow Flood - a Case Study of Xinfengjiang Reservoir

    Science.gov (United States)

    Chen, L.

    2017-12-01

    Building of reservoir shall impact the runoff production and routing characteristics, and changes the flood formation. This impact, called as reservoir flood effect, could be divided into three parts, including routing effect, volume effect and peak flow effect, and must be evaluated in a whole by using hydrological model. After analyzing the reservoir flood formation, the Liuxihe Model for reservoir flood forecasting is proposed. The Xinfengjiang Reservoir is studied as a case. Results show that the routing effect makes peak flow appear 4 to 6 hours in advance, volume effect is bigger for large flood than small one, and when rainfall focus on the reservoir area, this effect also increases peak flow largely, peak flow effect makes peak flow increase 6.63% to 8.95%. Reservoir flood effect is obvious, which have significant impact to reservoir flood. If this effect is not considered in the flood forecasting model, the flood could not be forecasted accurately, particularly the peak flow. Liuxihe Model proposed for Xinfengjiang Reservoir flood forecasting has a good performance, and could be used for real-time flood forecasting of Xinfengjiang Reservoir.Key words: Reservoir flood effect, reservoir flood forecasting, physically based distributed hydrological model, Liuxihe Model, parameter optimization

  20. Monitoring of levees, bridges, pipelines, and other critical infrastructure during the 2011 flooding in the Mississippi River Basin: Chapter J in 2011 floods of the central United States

    Science.gov (United States)

    Densmore, Brenda K.; Burton, Bethany L.; Dietsch, Benjamin J.; Cannia, James C.; Huizinga, Richard J.

    2014-01-01

    During the 2011 Mississippi River Basin flood, the U.S. Geological Survey evaluated aspects of critical river infrastructure at the request of and in support of local, State, and Federal Agencies. Geotechnical and hydrographic data collected by the U.S. Geological Survey at numerous locations were able to provide needed information about 2011 flood effects to those managing the critical infrastructure. These data were collected and processed in a short time frame to provide managers the ability to make a timely evaluation of the safety of the infrastructure and, when needed, to take action to secure and protect critical infrastructure. Critical infrastructure surveyed by the U.S. Geological Survey included levees, bridges, pipeline crossings, power plant intakes and outlets, and an electrical transmission tower. Capacitively coupled resistivity data collected along the flood-protection levees surrounding the Omaha Public Power District Nebraska City power plant (Missouri River Levee Unit R573), mapped the near-subsurface electrical properties of the levee and the materials immediately below it. The near-subsurface maps provided a better understanding of the levee construction and the nature of the lithology beneath the levee. Comparison of the capacitively coupled resistivity surveys and soil borings indicated that low-resistivity value material composing the levee generally is associated with lean clay and silt to about 2 to 4 meters below the surface, overlying a more resistive layer associated with sand deposits. In general, the resistivity structure becomes more resistive to the south and the southern survey sections correlate well with the borehole data that indicate thinner clay and silt at the surface and thicker sand sequences at depth in these sections. With the resistivity data Omaha Public Power District could focus monitoring efforts on areas with higher resistivity values (coarser-grained deposits or more loosely compacted section), which typically are

  1. Prevalencia del deterioro cognitivo leve en mayores institucionalizados Prevalencia of the mild cognitive impairment in institutionalized elders

    Directory of Open Access Journals (Sweden)

    Jesús Manuel Vallejo Sánchez

    2010-12-01

    Full Text Available Introducción y objetivo: el concepto de deterioro cognitivo leve (DCL define un estado previo en el declinar cognitivo hacia la demencia, donde se observan cambios cognitivos identificables mediante una adecuada evaluación clínica y neuropsicológica. Nuestro objetivo es conocer la prevalencia del deterioro cognitivo leve en la Residencia José Matía Calvo. Método: estudio observacional descriptivo transversal de los residentes institucionalizados con ausencia de patología neurológica o deterioro cognitivo severo de la Residencia de Mayores José Matía Calvo de Cádiz. Se cribó a los sujetos con el mini examen cognoscitivo en la versión de Lobo durante enero de 2008, obteniéndose una muestra de la que se estudiaron variables sociodemográficas y de control (estado cognitivo. Resultados: se desprende que la prevalencia de DCL en los ancianos institucionalizados en nuestro centro es del 27%, cifra más elevada que la aportada como media por algunos autores para la población general (15%-20%, pero menor que la establecida en otras residencias de mayores, que oscilan entre el 38,7% y el 44%. Conclusiones: el aumento constatado de la prevalencia del deterioro cognitivo en la población mayor y su repercusión en el nivel de independencia y calidad de vida de los mayores institucionalizados justifica la necesidad de identificar precozmente tal alteración para iniciar, lo antes posible, programas de intervención dirigidos a retrasar la dependencia, potenciar las capacidades residuales y mejorar la calidad de vida de estos ancianos.Introduction and objetive: the concept of Mild cognitive impairment defines a previous state in to decline cognitive towards the dementia, where are observed cognitive identifiable changes by means of a suitable clinical and evaluation and neuropsycological. To know the prevalencia of the cognitive slight deterioration in our center. Methods: observacional, descriptively and transversely study of the residents

  2. TRATAMENTO TÉRMICO DE PRECIPITAÇÃO - T6 APLICADO EM RODA DE LIGA LEVE DE MOTOCICLETA

    Directory of Open Access Journals (Sweden)

    Ricardo Orcélio Miranda de Oliveira

    2014-11-01

    Full Text Available As ligas de alumínio da série A356 (Al-Si-Mg são usadas extensivamente em componentes de manufatura para indústria automotiva e aeroespacial devido a suas propriedades físicas e mecânicas. São utilizadas em muitas aplicações estruturais que requerem uma alta resistência a baixo peso, alta resistência e tenacidade ao impacto, baixo coeficiente de expansão térmica, boa resistência à corrosão e excelente fluidez, como ligas de fundição para produção de rodas de liga leve. Nesse sentido, o objetivo principal deste trabalho é avaliar os efeitos do tratamento térmico de precipitação – T6 sobre a microestrutura e propriedades mecânicas da liga A356/Al-7Si-0,3Mg. Para tanto, uma roda de motocicleta foi utilizada e o tratamento térmico aplicado na própria indústria de fabricação, conforme padrões estabelecidos. Os resultados alcançados mostram uma microestrutura eutética composta de Si (esferoidizado mais os intermetálicos de Fe, que foram observados entre as ramificações interdendríticas. Ensaios de dureza Rocwell B foram realizados e os valores obtidos correspondem aos padrões estabelecidos.

  3. Application of PLT (Production Loggin Tool) surveys to select a vertical grid refinement in gas reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Pablo Julian [Petrosynergy Ltda., Sao Paulo, SP (Brazil); Schiozer, Denis Jose [Universidade Estadual de Campinas (UNISIM/UNICAMP), SP (Brazil). Dept. de Engenharia de Petroleo. Pesquisa em Simulacao e Gerenciamento de Reservatorios

    2012-07-01

    Most of the time, the fluid segregation in porous media between gas and water makes water breakthrough reach a well structurally from the bottom, even when coning effect is present. In this paper we describe a real case of a gas reservoir when water breakthrough reach the vertical well from the middle of the perforation, above gas phase. We also expose how to upgrade the geological model to represent the high permeability channels in the numerical simulation model. (author)

  4. Morphological elements of the Lofoten Basin Channel - implications for the properties of the latest turbidity currents

    Science.gov (United States)

    Laberg, J. S.; Forwick, M.; Johannesen, H. B.; Ivanov, M.; Kenyon, N. H.; Vorren, T. O.

    2009-04-01

    A modern turbidite system, the Andøya Canyon - Lofoten Basin Channel and associated deposits, is located on the continental margin offshore northern Norway (Laberg et al., 2005; 2007). Based on swath bathymetry, side-scan sonar records, and high-resolution seismic data, the Lofoten Basin Channel can be followed from the mouth of the canyon at the base of the continental slope into the abyssal plain of the Lofoten Basin. The proximal part of the channel is a straight erosional feature, up to 30 m deep and about 3 km wide with poorly developed levees. Coring retrieved sandy turbidites deposited both on the channel floor and on its levees. Thus, some of the most recent flows were sandy, up to 3 km wide and more than 30 m high in order to overspill the channel. About 50 km off the mouth of the Andøya Canyon, the Lofoten Basin Channel joins with another channel entering from the northeast. Beyond there is a complex sea floor morphology including one main channel, several smaller channels and various erosional features. The main channel terminates 20 - 30 km to the southwest. Further into the basin an elongated, positive lobe-formed deposit is located. In front of it part of an older, smaller lobe is seen. The main channel is continuing into the deepest part of the Lofoten Basin where it terminates at about 3200 m water depth. About 20 - 25 km from its termination the channel splits into several smaller (up to 500 m wide and 10 - 30 m high), meandering channels. The inter-channel areas are dominated by down-flow elongated scour marks, some located near and in parallel with the channels. These were probably formed by smaller flows confined by the meandering channels. Other scour marks are oriented parallel to the overall flow direction and were probably formed by larger unconfined flows that overtopped and moved independently of the meandering channels. The latter may have been up to an order of magnitude wider and higher compared to the confined flows. A depositional

  5. An index of reservoir habitat impairment

    Science.gov (United States)

    Miranda, L.E.; Hunt, K.M.

    2011-01-01

    Fish habitat impairment resulting from natural and anthropogenic watershed and in-lake processes has in many cases reduced the ability of reservoirs to sustain native fish assemblages and fisheries quality. Rehabilitation of impaired reservoirs is hindered by the lack of a method suitable for scoring impairment status. To address this limitation, an index of reservoir habitat impairment (IRHI) was developed by merging 14 metrics descriptive of common impairment sources, with each metric scored from 0 (no impairment) to 5 (high impairment) by fisheries scientists with local knowledge. With a plausible range of 5 to 25, distribution of the IRHI scores ranged from 5 to 23 over 482 randomly selected reservoirs dispersed throughout the USA. The IRHI reflected five impairment factors including siltation, structural habitat, eutrophication, water regime, and aquatic plants. The factors were weakly related to key reservoir characteristics including reservoir area, depth, age, and usetype, suggesting that common reservoir descriptors are poor predictors of fish habitat impairment. The IRHI is rapid and inexpensive to calculate, provides an easily understood measure of the overall habitat impairment, allows comparison of reservoirs and therefore prioritization of restoration activities, and may be used to track restoration progress. The major limitation of the IRHI is its reliance on unstandardized professional judgment rather than standardized empirical measurements. ?? 2010 US Government.

  6. Water resources review: Wheeler Reservoir, 1990

    Energy Technology Data Exchange (ETDEWEB)

    Wallus, R.; Cox, J.P.

    1990-09-01

    Protection and enhancement of water quality is essential for attaining the full complement of beneficial uses of TVA reservoirs. The responsibility for improving and protecting TVA reservoir water quality is shared by various federal, state, and local agencies, as well as the thousands of corporations and property owners whose individual decisions affect water quality. TVA's role in this shared responsibility includes collecting and evaluating water resources data, disseminating water resources information, and acting as a catalyst to bring together agencies and individuals that have a responsibility or vested interest in correcting problems that have been identified. This report is one in a series of status reports that will be prepared for each of TVA's reservoirs. The purpose of this status report is to provide an up-to-date overview of the characteristics and conditions of Wheeler Reservoir, including: reservoir purposes and operation; physical characteristics of the reservoir and the watershed; water quality conditions: aquatic biological conditions: designated, actual, and potential uses of the reservoir and impairments of those uses; ongoing or planned reservoir management activities. Information and data presented here are form the most recent reports, publications, and original data available. 21 refs., 8 figs., 29 tabs.

  7. Time-lapse seismic within reservoir engineering

    NARCIS (Netherlands)

    Oldenziel, T.

    2003-01-01

    Time-lapse 3D seismic is a fairly new technology allowing dynamic reservoir characterisation in a true volumetric sense. By investigating the differences between multiple seismic surveys, valuable information about changes in the oil/gas reservoir state can be captured. Its interpretation involves

  8. Monitoring programme of water reservoir Grliste

    International Nuclear Information System (INIS)

    Vuckovic, M; Milenkovic, P.; Lukic, D.

    2002-01-01

    The quality of surface waters is a very important problem incorporated in the environment protection, especially in water resources. The Timok border-land hasn't got sufficient underground and surface waters. This is certificated by the International Association for Water Resource. That was reason for building the water reservoir 'Grliste'. Drinking water from water reservoir 'Grliste' supplies Zajecar and the surroundings. (author)

  9. 49 CFR 393.50 - Reservoirs required.

    Science.gov (United States)

    2010-10-01

    ... depressing the brake pedal or treadle valve to the limit of its travel. (c) Safeguarding of air and vacuum... NECESSARY FOR SAFE OPERATION Brakes § 393.50 Reservoirs required. (a) Reservoir capacity for air-braked... driver to make a full service brake application with the engine stopped without depleting the air...

  10. Geothermal reservoir insurance study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-09

    The principal goal of this study was to provide analysis of and recommendations on the need for and feasibility of a geothermal reservoir insurance program. Five major tasks are reported: perception of risk by major market sectors, status of private sector insurance programs, analysis of reservoir risks, alternative government roles, and recommendations.

  11. Electromagnetic Heating Methods for Heavy Oil Reservoirs

    International Nuclear Information System (INIS)

    Sahni, A.; Kumar, M.; Knapp, R.B.

    2000-01-01

    The most widely used method of thermal oil recovery is by injecting steam into the reservoir. A well-designed steam injection project is very efficient in recovering oil, however its applicability is limited in many situations. Simulation studies and field experience has shown that for low injectivity reservoirs, small thickness of the oil-bearing zone, and reservoir heterogeneity limits the performance of steam injection. This paper discusses alternative methods of transferring heat to heavy oil reservoirs, based on electromagnetic energy. They present a detailed analysis of low frequency electric resistive (ohmic) heating and higher frequency electromagnetic heating (radio and microwave frequency). They show the applicability of electromagnetic heating in two example reservoirs. The first reservoir model has thin sand zones separated by impermeable shale layers, and very viscous oil. They model preheating the reservoir with low frequency current using two horizontal electrodes, before injecting steam. The second reservoir model has very low permeability and moderately viscous oil. In this case they use a high frequency microwave antenna located near the producing well as the heat source. Simulation results presented in this paper show that in some cases, electromagnetic heating may be a good alternative to steam injection or maybe used in combination with steam to improve heavy oil production. They identify the parameters which are critical in electromagnetic heating. They also discuss past field applications of electromagnetic heating including technical challenges and limitations

  12. Ichthyofauna of the reservoirs of Central Vietnam

    Directory of Open Access Journals (Sweden)

    I. A. Stolbunov

    2012-01-01

    Full Text Available Species composition, distribution and abundance of fish in the pelagic and littoral zone of four reservoirs of Central Vietnam (Suoi Chau, Kam Lam, Da Ban and Suoi Dau were studied first. According to the research data the fish community of the reservoirs is represented by 43 species of 19 fish families.

  13. Zooplankton of the Zaporiz’ke Reservoir

    Directory of Open Access Journals (Sweden)

    T. V. Mykolaichuk

    2006-01-01

    Full Text Available The paper is devoted to zooplankton species composition in the Zaporiz’ke Reservoir. The greatest species diversity was found in the macrophyte communities of the upper reservoir’s littoral, but the least zooplankton diversity – in the pelagic zone of the lower reservoir.

  14. Carbon emission from global hydroelectric reservoirs revisited.

    Science.gov (United States)

    Li, Siyue; Zhang, Quanfa

    2014-12-01

    Substantial greenhouse gas (GHG) emissions from hydropower reservoirs have been of great concerns recently, yet the significant carbon emitters of drawdown area and reservoir downstream (including spillways and turbines as well as river reaches below dams) have not been included in global carbon budget. Here, we revisit GHG emission from hydropower reservoirs by considering reservoir surface area, drawdown zone and reservoir downstream. Our estimates demonstrate around 301.3 Tg carbon dioxide (CO2)/year and 18.7 Tg methane (CH4)/year from global hydroelectric reservoirs, which are much higher than recent observations. The sum of drawdown and downstream emission, which is generally overlooked, represents 42 % CO2 and 67 % CH4 of the total emissions from hydropower reservoirs. Accordingly, the global average emissions from hydropower are estimated to be 92 g CO2/kWh and 5.7 g CH4/kWh. Nonetheless, global hydroelectricity could currently reduce approximate 2,351 Tg CO2eq/year with respect to fuel fossil plant alternative. The new findings show a substantial revision of carbon emission from the global hydropower reservoirs.

  15. Incorporating EM Inversion into Reservoir Monitoring

    NARCIS (Netherlands)

    Wirianto, M.; Mulder, W.A.; Slob, E.C.

    2012-01-01

    In the application of controlled source electromagnetics for reservoir monitoring on land, the timelapse signal measured with a surface-to-surface acquisition can reveal the lateral extent on the surface of resistivity changes at depth in a hydrocarbon reservoir under production. However, a direct

  16. Multiscale ensemble filtering for reservoir engineering applications

    NARCIS (Netherlands)

    Lawniczak, W.; Hanea, R.G.; Heemink, A.; McLaughlin, D.

    2009-01-01

    Reservoir management requires periodic updates of the simulation models using the production data available over time. Traditionally, validation of reservoir models with production data is done using a history matching process. Uncertainties in the data, as well as in the model, lead to a nonunique

  17. Economics of Developing Hot Stratigraphic Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Greg Mines; Hillary Hanson; Rick Allis; Joseph Moore

    2014-09-01

    Stratigraphic geothermal reservoirs at 3 – 4 km depth in high heat-flow basins are capable of sustaining 100 MW-scale power plants at about 10 c/kWh. This paper examines the impacts on the levelized cost of electricity (LCOE) of reservoir depth and temperature, reservoir productivity, and drillhole/casing options. For a reservoir at 3 km depth with a moderate productivity index by hydrothermal reservoir standards (about 50 L/s/MPa, 5.6 gpm/psi), an LCOE of 10c/kWh requires the reservoir to be at about 200°C. This is the upper temperature limit for pumps. The calculations assume standard hydrothermal drilling costs, with the production interval completed with a 7 inch liner in an 8.5 inch hole. If a reservoir at 4 km depth has excellent permeability characteristics with a productivity index of 100 L/s/MPa (11.3 gpm/psi), then the LCOE is about 11 c/kWh assuming the temperature decline rate with development is not excessive (< 1%/y, with first thermal breakthrough delayed by about 10 years). Completing wells with modest horizontal legs (e.g. several hundred meters) may be important for improving well productivity because of the naturally high, sub-horizontal permeability in this type of reservoir. Reducing the injector/producer well ratio may also be cost-effective if the injectors are drilled as larger holes.

  18. A baixa estatura leve está associada ao aumento da pressão arterial em adolescentes com sobrepeso La baja estatura leve está asociada al aumento de la presión arterial en adolescentes con sobrepeso Mild stunting is associated with higher blood pressure in overweight adolescents

    Directory of Open Access Journals (Sweden)

    Ana Paula Grotti Clemente

    2012-01-01

    Full Text Available FUNDAMENTO: Estudos têm demonstrado que a desnutrição pré/pós-natal leva a um maior risco de doenças não transmissíveis, como diabetes, hipertensão e obesidade na idade adulta. OBJETIVO: Determinar se os adolescentes com sobrepeso e desnutrição leve [escores-Z altura/idade (HAZ na faixa de -2] têm pressão arterial mais elevada do que os indivíduos com sobrepeso e com estatura normal (HAZ > -1. MÉTODOS: Os participantes foram classificados como de baixa estatura leve ou de estatura normal, e estratificados de acordo com os percentis de massa corporal para a idade, como sobrepeso, peso normal ou abaixo do peso. As pressões arteriais sistólica (PAS e diastólica (PAD foram determinadas de acordo com as diretrizes e a gordura abdominal foi analisada por absorciometria de dupla emissão de raios-X. RESULTADOS: Indivíduos com baixa estatura leve e sobrepeso apresentaram valores mais elevados da PAD (p = 0,001 do que suas contrapartes de baixo peso (69,75 ± 12,03 e 54,46 ± 11,24 mmHg, respectivamente, mas semelhantes àqueles com IMC normal. Não foram encontradas diferenças nos valores de PAD em indivíduos normais, indivíduos com sobrepeso e com baixo peso entre os grupos de estatura normal. Foi encontrado um aumento na PAS (p = 0,01 entre os indivíduos com baixa estatura leve quando comparados os indivíduos com sobrepreso com suas contrapartes de baixo peso e IMC normal (114,70 ± 15,46, 97,38 ± 10,87 e 104,72 ± 12,24 mmHg, respectivamente. Embora não tenham sido observadas diferenças nas médias de PAS entre os grupos de baixa estatura leve e estatura normal, foi encontrado um intercepto significativo (p = 0,01, revelando maior PAS entre os indivíduos com baixa estatura leve. Houve correlação entre PAS e gordura abdominal (r = 0,42, ρ = 0,02 no grupo com baixa estatura leve. CONCLUSÃO: Indivíduos de baixa estatura leve com sobrepeso apresentaram maior PAS do que os de estatura normal e sobrepeso. Esses achados

  19. The freshwater reservoir effect in radiocarbon dating

    DEFF Research Database (Denmark)

    Philippsen, Bente

    2013-01-01

    effect on radiocarbon dating in an estuarine environment is examined. Here, freshwater influence causes reservoir ages to vary between 250 and 700 14C years during the period 5400 BC - AD 700. The examples in this study show clearly that the freshwater reservoir effect can seriously corrupt radiocarbon......The freshwater reservoir effect can result in anomalously old radiocarbon ages of samples from lakes and rivers. This includes the bones of people whose subsistence was based on freshwater fish, and pottery in which fish was cooked. Water rich in dissolved ancient calcium carbonates, commonly known...... as hard water, is the most common reason for the freshwater reservoir effect. It is therefore also called hardwater effect. Although it has been known for more than 60 years, it is still less well-recognized by archaeologists than the marine reservoir effect. The aim of this study is to examine the order...

  20. Some practical aspects of reservoir management

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, M.L.; Young, M.A.; Cole, E.L.; Madden, M.P. [BDM-Oklahoma, Bartlesville, OK (United States)

    1996-09-01

    The practical essence of reservoir management is the optimal application of available resources-people, equipment, technology, and money to maximize profitability and recovery. Success must include knowledge and consideration of (1) the reservoir system, (2) the technologies available, and (3) the reservoir management business environment. Two Reservoir Management Demonstration projects (one in a small, newly-discovered field and one in a large, mature water-flood) implemented by the Department of Energy through BDM-Oklahoma illustrate the diversity of situations suited for reservoir management efforts. Project teams made up of experienced engineers, geoscientists, and other professionals arrived at an overall reservoir management strategy for each field. in 1993, Belden & Blake Corporation discovered a regionally significant oil reservoir (East Randolph Field) in the Cambrian Rose Run formation in Portage County, Ohio. Project objectives are to improve field operational economics and optimize oil recovery. The team focused on characterizing the reservoir geology and analyzing primary production and reservoir data to develop simulation models. Historical performance was simulated and predictions were made to assess infill drilling, water flooding, and gas repressurization. The Citronelle Field, discovered in 1955 in Mobile County, Alabama, has produced 160 million barrels from fluvial sandstones of the Cretaceous Rodessa formation. Project objectives are to address improving recovery through waterflood optimization and problems related to drilling, recompletions, production operations, and regulatory and environmental issues. Initial efforts focused on defining specific problems and on defining a geographic area within the field where solutions might best be pursued. Geologic and reservoir models were used to evaluate past performance and to investigate improved recovery operations.

  1. The Alphabet Soup of HIV Reservoir Markers.

    Science.gov (United States)

    Sharaf, Radwa R; Li, Jonathan Z

    2017-04-01

    Despite the success of antiretroviral therapy in suppressing HIV, life-long therapy is required to avoid HIV reactivation from long-lived viral reservoirs. Currently, there is intense interest in searching for therapeutic interventions that can purge the viral reservoir to achieve complete remission in HIV patients off antiretroviral therapy. The evaluation of such interventions relies on our ability to accurately and precisely measure the true size of the viral reservoir. In this review, we assess the most commonly used HIV reservoir assays, as a clear understanding of the strengths and weaknesses of each is vital for the accurate interpretation of results and for the development of improved assays. The quantification of intracellular or plasma HIV RNA or DNA levels remains the most commonly used tests for the characterization of the viral reservoir. While cost-effective and high-throughput, these assays are not able to differentiate between replication-competent or defective fractions or quantify the number of infected cells. Viral outgrowth assays provide a lower bound for the fraction of cells that can produce infectious virus, but these assays are laborious, expensive and substantially underestimate the potential reservoir of replication-competent provirus. Newer assays are now available that seek to overcome some of these problems, including full-length proviral sequencing, inducible HIV RNA assays, ultrasensitive p24 assays and murine adoptive transfer techniques. The development and evaluation of strategies for HIV remission rely upon our ability to accurately and precisely quantify the size of the remaining viral reservoir. At this time, all current HIV reservoir assays have drawbacks such that combinations of assays are generally needed to gain a more comprehensive view of the viral reservoir. The development of novel, rapid, high-throughput assays that can sensitively quantify the levels of the replication-competent HIV reservoir is still needed.

  2. Reservoir Identification: Parameter Characterization or Feature Classification

    Science.gov (United States)

    Cao, J.

    2017-12-01

    The ultimate goal of oil and gas exploration is to find the oil or gas reservoirs with industrial mining value. Therefore, the core task of modern oil and gas exploration is to identify oil or gas reservoirs on the seismic profiles. Traditionally, the reservoir is identify by seismic inversion of a series of physical parameters such as porosity, saturation, permeability, formation pressure, and so on. Due to the heterogeneity of the geological medium, the approximation of the inversion model and the incompleteness and noisy of the data, the inversion results are highly uncertain and must be calibrated or corrected with well data. In areas where there are few wells or no well, reservoir identification based on seismic inversion is high-risk. Reservoir identification is essentially a classification issue. In the identification process, the underground rocks are divided into reservoirs with industrial mining value and host rocks with non-industrial mining value. In addition to the traditional physical parameters classification, the classification may be achieved using one or a few comprehensive features. By introducing the concept of seismic-print, we have developed a new reservoir identification method based on seismic-print analysis. Furthermore, we explore the possibility to use deep leaning to discover the seismic-print characteristics of oil and gas reservoirs. Preliminary experiments have shown that the deep learning of seismic data could distinguish gas reservoirs from host rocks. The combination of both seismic-print analysis and seismic deep learning is expected to be a more robust reservoir identification method. The work was supported by NSFC under grant No. 41430323 and No. U1562219, and the National Key Research and Development Program under Grant No. 2016YFC0601

  3. Reservoir management under geological uncertainty using fast model update

    NARCIS (Netherlands)

    Hanea, R.; Evensen, G.; Hustoft, L.; Ek, T.; Chitu, A.; Wilschut, F.

    2015-01-01

    Statoil is implementing "Fast Model Update (FMU)," an integrated and automated workflow for reservoir modeling and characterization. FMU connects all steps and disciplines from seismic depth conversion to prediction and reservoir management taking into account relevant reservoir uncertainty. FMU

  4. Distribution and decontamination of radioactive cesium in small-scale agricultural reservoirs of Fukushima Prefecture

    International Nuclear Information System (INIS)

    Okumura, Hiroshi; Yamamoto, Atsushi; Inagaki, Masayo; Yamanishi, Hirokuni; Itoh, Tetsuo

    2015-01-01

    The authors studied optimal methods against the Cs contamination of agricultural reservoirs outside the evacuation zones, which had been contaminated by the accident of Fukushima Daiichi Nuclear Power Station. As a result of measurements at three points of a small reservoir, the highest radioactivity value was 16.8 Bq/g, with a higher value at bank part and bottom mud. The possibility is considered that the bank part held an organic layer with accumulated Cs, and the bottom mud had litters and clay soil that adsorbed Ce. The distribution of Cs was fluctuated depending on the environment of reservoirs, with the effects of the influx of sediment, influx of litters, and landform of catchment areas. In the 'Technical manual on measures against radioactive materials at reservoirs,' published by the Ministry of Agriculture, Forestry and Fisheries, three decontamination methods for reservoirs have been taken up: (1) removal of mud, (2) fixation of bottom mud, and (3) improvement of water intake method. The method (1) and (2) alone cannot cope with re-contamination from water catchment areas. As a countermeasure for recontamination after decontamination, it is good to install a headrace channel, slope, retaining part, etc. at the pond bottom, to increase the efficiency of the recollection and immobilization of Ce. The felling of neighboring trees, litter collection in peripheral areas, and covering measures for the surface layer in the vicinity are essential. (A.O.)

  5. Towards pattern generation and chaotic series prediction with photonic reservoir computers

    Science.gov (United States)

    Antonik, Piotr; Hermans, Michiel; Duport, François; Haelterman, Marc; Massar, Serge

    2016-03-01

    Reservoir Computing is a bio-inspired computing paradigm for processing time dependent signals that is particularly well suited for analog implementations. Our team has demonstrated several photonic reservoir computers with performance comparable to digital algorithms on a series of benchmark tasks such as channel equalisation and speech recognition. Recently, we showed that our opto-electronic reservoir computer could be trained online with a simple gradient descent algorithm programmed on an FPGA chip. This setup makes it in principle possible to feed the output signal back into the reservoir, and thus highly enrich the dynamics of the system. This will allow to tackle complex prediction tasks in hardware, such as pattern generation and chaotic and financial series prediction, which have so far only been studied in digital implementations. Here we report simulation results of our opto-electronic setup with an FPGA chip and output feedback applied to pattern generation and Mackey-Glass chaotic series prediction. The simulations take into account the major aspects of our experimental setup. We find that pattern generation can be easily implemented on the current setup with very good results. The Mackey-Glass series prediction task is more complex and requires a large reservoir and more elaborate training algorithm. With these adjustments promising result are obtained, and we now know what improvements are needed to match previously reported numerical results. These simulation results will serve as basis of comparison for experiments we will carry out in the coming months.

  6. Reservoir Sedimentation and Upstream Sediment Sources: Perspectives and Future Research Needs on Streambank and Gully Erosion

    Science.gov (United States)

    Fox, G. A.; Sheshukov, A.; Cruse, R.; Kolar, R. L.; Guertault, L.; Gesch, K. R.; Dutnell, R. C.

    2016-05-01

    The future reliance on water supply and flood control reservoirs across the globe will continue to expand, especially under a variable climate. As the inventory of new potential dam sites is shrinking, construction of additional reservoirs is less likely compared to simultaneous flow and sediment management in existing reservoirs. One aspect of this sediment management is related to the control of upstream sediment sources. However, key research questions remain regarding upstream sediment loading rates. Highlighted in this article are research needs relative to measuring and predicting sediment transport rates and loading due to streambank and gully erosion within a watershed. For example, additional instream sediment transport and reservoir sedimentation rate measurements are needed across a range of watershed conditions, reservoir sizes, and geographical locations. More research is needed to understand the intricate linkage between upland practices and instream response. A need still exists to clarify the benefit of restoration or stabilization of a small reach within a channel system or maturing gully on total watershed sediment load. We need to better understand the intricate interactions between hydrological and erosion processes to improve prediction, location, and timing of streambank erosion and failure and gully formation. Also, improved process-based measurement and prediction techniques are needed that balance data requirements regarding cohesive soil erodibility and stability as compared to simpler topographic indices for gullies or stream classification systems. Such techniques will allow the research community to address the benefit of various conservation and/or stabilization practices at targeted locations within watersheds.

  7. Study on fine geological modelling of the fluvial sandstone reservoir in Daqing oilfield

    Energy Technology Data Exchange (ETDEWEB)

    Zhoa Han-Qing [Daqing Research Institute, Helongjiang (China)

    1997-08-01

    These paper aims at developing a method for fine reservoir description in maturing oilfields by using close spaced well logging data. The main productive reservoirs in Daqing oilfield is a set of large fluvial-deltaic deposits in the Songliao Lake Basin, characterized by multi-layers and serious heterogeneities. Various fluvial channel sandstone reservoirs cover a fairly important proportion of reserves. After a long period of water flooding, most of them have turned into high water cut layers, but there are considerable residual reserves within them, which are difficult to find and tap. Making fine reservoir description and developing sound a geological model is essential for tapping residual oil and enhancing oil recovery. The principal reason for relative lower precision of predicting model developed by using geostatistics is incomplete recognition of complex distribution of fluvial reservoirs and their internal architecture`s. Tasking advantage of limited outcrop data from other regions (suppose no outcrop data available in oilfield) can only provide the knowledge of subtle changing of reservoir parameters and internal architecture. For the specific geometry distribution and internal architecture of subsurface reservoirs (such as in produced regions) can be gained only from continuous infilling logging well data available from studied areas. For developing a geological model, we think the first important thing is to characterize sandbodies geometries and their general architecture`s, which are the framework of models, and then the slight changing of interwell parameters and internal architecture`s, which are the contents and cells of the model. An excellent model should possess both of them, but the geometry is the key to model, because it controls the contents and cells distribution within a model.

  8. Channel-Mediated Lactate Release by K+-Stimulated Astrocytes

    KAUST Repository

    Sotelo-Hitschfeld, T.

    2015-03-11

    Excitatory synaptic transmission is accompanied by a local surge in interstitial lactate that occurs despite adequate oxygen availability, a puzzling phenomenon termed aerobic glycolysis. In addition to its role as an energy substrate, recent studies have shown that lactate modulates neuronal excitability acting through various targets, including NMDA receptors and G-protein-coupled receptors specific for lactate, but little is known about the cellular and molecular mechanisms responsible for the increase in interstitial lactate. Using a panel of genetically encoded fluorescence nanosensors for energy metabolites, we show here that mouse astrocytes in culture, in cortical slices, and in vivo maintain a steady-state reservoir of lactate. The reservoir was released to the extracellular space immediately after exposure of astrocytes to a physiological rise in extracellular K+ or cell depolarization. Cell-attached patch-clamp analysis of cultured astrocytes revealed a 37 pS lactate-permeable ion channel activated by cell depolarization. The channel was modulated by lactate itself, resulting in a positive feedback loop for lactate release. A rapid fall in intracellular lactate levels was also observed in cortical astrocytes of anesthetized mice in response to local field stimulation. The existence of an astrocytic lactate reservoir and its quick mobilization via an ion channel in response to a neuronal cue provides fresh support to lactate roles in neuronal fueling and in gliotransmission.

  9. Calibration of Seismic Attributes for Reservoir Characterization; ANNUAL

    International Nuclear Information System (INIS)

    Pennington, Wayne D.; Acevedo, Horacio; Green, Aaron; Len, Shawn; Minavea, Anastasia; Wood, James; Xie, Deyi

    2002-01-01

    This project has completed the initially scheduled third year of the contract, and is beginning a fourth year, designed to expand upon the tech transfer aspects of the project. From the Stratton data set, demonstrated that an apparent correlation between attributes derived along 'phantom' horizons are artifacts of isopach changes; only if the interpreter understands that the interpretation is based on this correlation with bed thickening or thinning, can reliable interpretations of channel horizons and facies be made. From the Boonsville data set , developed techniques to use conventional seismic attributes, including seismic facies generated under various neural network procedures, to subdivide regional facies determined from logs into productive and non-productive subfacies, and developed a method involving cross-correlation of seismic waveforms to provide a reliable map of the various facies present in the area. The Teal South data set provided a surprising set of data, leading us to develop a pressure-dependent velocity relationship and to conclude that nearby reservoirs are undergoing a pressure drop in response to the production of the main reservoir, implying that oil is being lost through their spill points, never to be produced. The Wamsutter data set led to the use of unconventional attributes including lateral incoherence and horizon-dependent impedance variations to indicate regions of former sand bars and current high pressure, respectively, and to evaluation of various upscaling routines

  10. Visualization of viscous coupling effects in heavy oil reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz-Arango, J.D. [Calgary Univ., AB (Canada). Tomographic Imaging and Porous Media Laboratory; Kantzas, A. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Calgary Univ., AB (Canada). Tomographic Imaging and Porous Media Laboratory

    2008-10-15

    Some heavy oil reservoirs in Venezuela and Canada have shown higher than expected production rates attributed to the effects of foamy oil or enhanced solution gas drive. However, foamy oil 2-phase flow does not fully explain oil rate enhancement in heavy oil reservoirs. In this study, flow visualization experiments were conducted in a 2-D etched network micromodel in order to determine the effect of the viscosity ratio on oil mobility at the pore scale. The micromodel's pattern was characterized by macroscopic heterogeneities with a random network of larger pore bodies interconnected with a random network of smaller pore throats. Displacement tests were conducted with green-dyed distilled water as a wetting phase. N-octane, bromododecane and mineral oil were used as non-wetting phases. An unsteady-state method was used to obtain displacement data, and the Alternate method was used to calculate relative permeabilities. Results of the study showed that relative permeabilities depended on the viscosity ratio of the fluids flowing through the porous medium. Channel and annular flows co-existed, and water lubrication was stronger at higher water saturations. The results of the study explained the abnormally high production rates in heavier oil fields. 19 refs., 3 tabs., 14 figs.

  11. A method for improving predictions of bed-load discharges to reservoirs

    Science.gov (United States)

    Lopes, V.L.; Osterkamp, W.R.; Bravo-Espinosa, M.

    2007-01-01

    Effective management options for mitigating the loss of reservoir water storage capacity to sedimentation depend on improved predictions of bed-load discharges into the reservoirs. Most predictions of bed-load discharges, however, are based on the assumption that the rates of bed-load sediment availability equal the transport capacity of the flow, ignoring the spatio-temporal variability of the sediment supply. This paper develops a semiquantitative method to characterize bed-load sediment transport in alluvial channels, assuming a channel reach is non-supply limited when the bed-load discharge of a given sediment particle-size class is functionally related to the energy that is available to transport that fraction of the total bed-load. The method was applied to 22 alluvial stream channels in the USA to determine whether a channel reach had a supply-limited or non-supply-limited bed-load transport regime. The non-supply-limited transport regime was further subdivided into two groups on the basis of statistical tests. The results indicated the pattern of bed-load sediment transport in alluvial channels depends on the complete spectrum of sediment particle sizes available for transport rather than individual particle-size fractions represented by one characteristic particle size. The application of the method developed in this paper should assist reservoir managers in selecting bed-load sediment transport equations to improve predictions of bed-load discharge in alluvial streams, thereby significantly increasing the efficiency of management options for maintaining the storage capacity of waterbodies. ?? 2007 Blackwell Publishing Asia Pty Ltd.

  12. HIPPI and Fibre Channel

    International Nuclear Information System (INIS)

    Tolmie, D.E.

    1992-01-01

    The High-Performance Parallel Interface (HIPPI) and Fibre Channel are near-gigabit per second data communications interfaces being developed in ANSI standards Task Group X3T9.3. HIPPI is the current interface of choice in the high-end and supercomputer arena, and Fibre Channel is a follow-on effort. HIPPI came from a local area network background, and Fibre Channel came from a mainframe to peripheral interface background

  13. ASUD2- decision support system on Dnieper reservoirs operations taking into account environmental priorities

    Science.gov (United States)

    Iritz, L.; Zheleznyak, M.; Dvorzhak, A.; Nesterov, A.; Zaslavsky, A.

    2003-04-01

    basis of the different optimisation criteria minimum of the distance to the trajectory of the water level given by decision of the Joint River Commission, minimum value of the water contamination parameters (DO, nutrients, phosphorus), maximum energy production, taking into account limitations from fishery, water intakes of irrigation and transport channels etc; -water releases from the reservoirs to maintain the recommended dynamics in the whole Dnieper Cascade; -integrated water quality parameters for all reservoirs and distributed water quality parameters for the two largest reservoirs (Kremenchug and Kachovka). The analyses based on economical criteria provides the cost-benefit evaluation for different reservoir management alternatives. The assessment takes into account energy production, industry, agriculture as well as the costs associated with ecological damages.

  14. Top-Down, Intelligent Reservoir Model

    Science.gov (United States)

    Mohaghegh, Shahab

    2010-05-01

    Conventional reservoir simulation and modeling is a bottom-up approach. It starts with building a geological model of the reservoir that is populated with the best available petrophysical and geophysical information at the time of development. Engineering fluid flow principles are added and solved numerically so as to arrive at a dynamic reservoir model. The dynamic reservoir model is calibrated using the production history of multiple wells and the history matched model is used to strategize field development in order to improve recovery. Top-Down, Intelligent Reservoir Modeling approaches the reservoir simulation and modeling from an opposite angle by attempting to build a realization of the reservoir starting with the measured well production behavior (history). The production history is augmented by core, log, well test and seismic data in order to increase the accuracy of the Top-Down modeling technique. Although not intended as a substitute for the conventional reservoir simulation of large, complex fields, this novel approach to reservoir modeling can be used as an alternative (at a fraction of the cost) to conventional reservoir simulation and modeling in cases where performing conventional modeling is cost (and man-power) prohibitive. In cases where a conventional model of a reservoir already exists, Top-Down modeling should be considered as a compliment to, rather than a competition for the conventional technique, to provide an independent look at the data coming from the reservoir/wells for optimum development strategy and recovery enhancement. Top-Down, Intelligent Reservoir Modeling starts with well-known reservoir engineering techniques such as Decline Curve Analysis, Type Curve Matching, History Matching using single well numerical reservoir simulation, Volumetric Reserve Estimation and calculation of Recovery Factors for all the wells (individually) in the field. Using statistical techniques multiple Production Indicators (3, 6, and 9 months cum

  15. An experimental unification of reservoir computing methods.

    Science.gov (United States)

    Verstraeten, D; Schrauwen, B; D'Haene, M; Stroobandt, D

    2007-04-01

    Three different uses of a recurrent neural network (RNN) as a reservoir that is not trained but instead read out by a simple external classification layer have been described in the literature: Liquid State Machines (LSMs), Echo State Networks (ESNs) and the Backpropagation Decorrelation (BPDC) learning rule. Individual descriptions of these techniques exist, but a overview is still lacking. Here, we present a series of experimental results that compares all three implementations, and draw conclusions about the relation between a broad range of reservoir parameters and network dynamics, memory, node complexity and performance on a variety of benchmark tests with different characteristics. Next, we introduce a new measure for the reservoir dynamics based on Lyapunov exponents. Unlike previous measures in the literature, this measure is dependent on the dynamics of the reservoir in response to the inputs, and in the cases we tried, it indicates an optimal value for the global scaling of the weight matrix, irrespective of the standard measures. We also describe the Reservoir Computing Toolbox that was used for these experiments, which implements all the types of Reservoir Computing and allows the easy simulation of a wide range of reservoir topologies for a number of benchmarks.

  16. Stochastic Reservoir Characterization Constrained by Seismic Data

    Energy Technology Data Exchange (ETDEWEB)

    Eide, Alfhild Lien

    1999-07-01

    In order to predict future production of oil and gas from a petroleum reservoir, it is important to have a good description of the reservoir in terms of geometry and physical parameters. This description is used as input to large numerical models for the fluid flow in the reservoir. With increased quality of seismic data, it is becoming possible to extend their use from the study of large geologic structures such as seismic horizons to characterization of the properties of the reservoir between the horizons. Uncertainties because of the low resolution of seismic data can be successfully handled by means of stochastic modeling, and spatial statistics can provide tools for interpolation and simulation of reservoir properties not completely resolved by seismic data. This thesis deals with stochastic reservoir modeling conditioned to seismic data and well data. Part I presents a new model for stochastic reservoir characterization conditioned to seismic traces. Part II deals with stochastic simulation of high resolution impedance conditioned to measured impedance. Part III develops a new stochastic model for calcite cemented objects in a sandstone background; it is a superposition of a marked point model for the calcites and a continuous model for the background.

  17. Caracterização de massas cerâmicas do estado de S. Paulo para produção de agregados leves para concreto

    Directory of Open Access Journals (Sweden)

    B. C. Santis

    2013-06-01

    Full Text Available Este trabalho tem por objetivo a caracterização de diferentes massas cerâmicas do estado de S. Paulo para a produção de agregados leves de argila calcinada visando à utilização em concretos de cimento Portland. A caracterização das massas cerâmicas deu-se por meio das técnicas de limites de liquidez e plasticidade, análise granulométrica, análise química e difração de raios X. Os corpos de prova confeccionados com essas massas cerâmicas, queimados a 900 ºC, foram caracterizados por meio da avaliação da retração linear, absorção de água, porosidade aparente, massa específica aparente, expansão por umidade e resistência à compressão. Os resultados desta pesquisa indicaram a viabilidade da produção de agregados leves de argila calcinada para utilização em concretos e os valores da massa específica (1,555 a 1,785 kg/m³ e da resistência à compressão (18,0 a 55,8 MPa apresentaram-se em um patamar intermediário entre os observados para a argila expandida (agregado leve comercial e para o agregado convencional (basalto.

  18. Intervenções de Cessação de Tabagismo em Fumantes Leves: Uma Revisão Sistemática

    Directory of Open Access Journals (Sweden)

    Taynara Dutra Batista Formagini

    2015-12-01

    Full Text Available Apesar da diminuição da prevalência de fumantes, o número de tabagistas de baixo consumo de cigarro tem aumentado, comumente denominados de fumantes leves ou intermitentes. É sabido que qualquer quantidade de consumo de tabaco pode trazer danos à saúde. A pesquisa sobre essa população é escassa e pouco se sabe sobre intervenções de cessação de tabagismo direcionadas a esses grupos. Dessa forma, o objetivo do presente estudo foi realizar uma revisão sistemática a fim de descrever estudos que apresentam intervenções para fumantes leves e intermitentes. As pesquisas foram conduzidas nas bases de dados PubMed, PsycInfo, SciELO e Pepsic. Palavras-chave incluíram: [light smoker, non-daily smoker, intermittent smoker; social smoking, occasional smoking, low-level smoking] AND [intervention studies, clinical trial and evaluation studies] AND [tobacco use cessation, tobacco use disorder]. Nove artigos preencheram os critérios de inclusão e foram analisados. Os resultados apontaram que intervenções bem-sucedidas incluíram aconselhamento e uso de medicamentos, tais como intervenção breve, tratamento de reposição de nicotina, Vareniclina, educação em saúde, entre outros. No entanto, intervenções ainda estão em estágio inicial. Destaca-se a necessidade de mais investigações sobre intervenções específicas para fumantes de baixo consumo, desenvolvimento de escalas de dependência exclusivas para esse grupo e estudos epidemiológicos para compreender quem são os fumantes leves e intermitentes, especialmente no Brasil.

  19. Ion Channels in Leukocytes

    Science.gov (United States)

    1991-07-01

    be fitted to a Hodgkin - conductance. K (1.0) > Rb (0.77) > NH4 (0.10) > Cs Huxley type n4j model (17, 38). However, the rate of K0 (0.02) > Na (ɘ.01...15, 25 activated) T- and B-cells, murine B-cells? SCG, single-channel conductance under physiological ionic gradient- tfor ructif~ y ig ehannel, largest...the channel induces a confor- kat T-cell line (52). Fina:! y , single-channel recordings of mational change that ina.-tix ates the channel rather human T

  20. A channel profile analyser

    International Nuclear Information System (INIS)

    Gobbur, S.G.

    1983-01-01

    It is well understood that due to the wide band noise present in a nuclear analog-to-digital converter, events at the boundaries of adjacent channels are shared. It is a difficult and laborious process to exactly find out the shape of the channels at the boundaries. A simple scheme has been developed for the direct display of channel shape of any type of ADC on a cathode ray oscilliscope display. This has been accomplished by sequentially incrementing the reference voltage of a precision pulse generator by a fraction of a channel and storing ADC data in alternative memory locations of a multichannel pulse height analyser. Alternative channels are needed due to the sharing at the boundaries of channels. In the flat region of the profile alternate memory locations are channels with zero counts and channels with the full scale counts. At the boundaries all memory locations will have counts. The shape of this is a direct display of the channel boundaries. (orig.)

  1. Soldagem por ponto no estado sólido de ligas leves Solid state spot welding of lightweight alloys

    Directory of Open Access Journals (Sweden)

    Leonardo Contri Campanelli

    2011-09-01

    Full Text Available A recente preocupação quanto às mudanças climáticas vem impulsionando pesquisas em eficiência energética dos meios de transportes no sentido de reduzir a emissão de gases. Uma das principais soluções consiste na redução do peso estrutural através da aplicação de novos materiais, como as ligas leves de alumínio e magnésio. Entretanto, novos usos ficam muitas vezes limitados pela dificuldade de união desses materiais. A técnica de soldagem por fricção e mistura (FSW é um processo de união no estado sólido que surge como uma alternativa viável para substituir ou complementar as tecnologias de união consagradas. Como uma junta contínua não é sempre a requisitada, duas tecnologias de união por ponto derivadas do FSW estão em desenvolvimento: soldagem por fricção e mistura por ponto (FSSW e soldagem por fricção por ponto (FSpW. Além de fornecerem juntas de elevada resistência e praticamente isentas de defeitos, estas técnicas apresentam alta eficiência energética, curto ciclo de soldagem, facilidade de automação e compatibilidade com o meio-ambiente, fazendo frente às técnicas convencionais de união por ponto, como a soldagem por resistência por ponto (RSW e a rebitagem.The recent concern about climate change has stimulated research into transport energy efficiency in order to reduce the emission of gases. One of the main solutions is to reduce the structural weight through the application of new materials, such as aluminum and magnesium lightweight alloys. However, new applications are often limited by the difficulty of joining these materials. Friction Stir Welding (FSW is a solid state joining technique that emerges as a viable alternative to replace or complement the established joining technologies. As a continuous weld is not always requested, two spot welding technologies derived from FSW are under development: Friction Stir Spot Welding (FSSW and Friction Spot Welding (FSpW. Besides providing

  2. Reflection Phenomena in Underground Pumped Storage Reservoirs

    Directory of Open Access Journals (Sweden)

    Elena Pummer

    2018-04-01

    Full Text Available Energy storage through hydropower leads to free surface water waves in the connected reservoirs. The reason for this is the movement of water between reservoirs at different elevations, which is necessary for electrical energy storage. Currently, the expansion of renewable energies requires the development of fast and flexible energy storage systems, of which classical pumped storage plants are the only technically proven and cost-effective technology and are the most used. Instead of classical pumped storage plants, where reservoirs are located on the surface, underground pumped storage plants with subsurface reservoirs could be an alternative. They are independent of topography and have a low surface area requirement. This can be a great advantage for energy storage expansion in case of environmental issues, residents’ concerns and an unusable terrain surface. However, the reservoirs of underground pumped storage plants differ in design from classical ones for stability and space reasons. The hydraulic design is essential to ensure their satisfactory hydraulic performance. The paper presents a hybrid model study, which is defined here as a combination of physical and numerical modelling to use the advantages and to compensate for the disadvantages of the respective methods. It shows the analysis of waves in ventilated underground reservoir systems with a great length to height ratio, considering new operational aspects from energy supply systems with a great percentage of renewable energies. The multifaceted and narrow design of the reservoirs leads to complex free surface flows; for example, undular and breaking bores arise. The results show excessive wave heights through wave reflections, caused by the impermeable reservoir boundaries. Hence, their knowledge is essential for a successful operational and constructive design of the reservoirs.

  3. Improving reservoir history matching of EM heated heavy oil reservoirs via cross-well seismic tomography

    KAUST Repository

    Katterbauer, Klemens

    2014-01-01

    Enhanced recovery methods have become significant in the industry\\'s drive to increase recovery rates from oil and gas reservoirs. For heavy oil reservoirs, the immobility of the oil at reservoir temperatures, caused by its high viscosity, limits the recovery rates and strains the economic viability of these fields. While thermal recovery methods, such as steam injection or THAI, have extensively been applied in the field, their success has so far been limited due to prohibitive heat losses and the difficulty in controlling the combustion process. Electromagnetic (EM) heating via high-frequency EM radiation has attracted attention due to its wide applicability in different environments, its efficiency, and the improved controllability of the heating process. While becoming a promising technology for heavy oil recovery, its effect on overall reservoir production and fluid displacements are poorly understood. Reservoir history matching has become a vital tool for the oil & gas industry to increase recovery rates. Limited research has been undertaken so far to capture the nonlinear reservoir dynamics and significantly varying flow rates for thermally heated heavy oil reservoir that may notably change production rates and render conventional history matching frameworks more challenging. We present a new history matching framework for EM heated heavy oil reservoirs incorporating cross-well seismic imaging. Interfacing an EM heating solver to a reservoir simulator via Andrade’s equation, we couple the system to an ensemble Kalman filter based history matching framework incorporating a cross-well seismic survey module. With increasing power levels and heating applied to the heavy oil reservoirs, reservoir dynamics change considerably and may lead to widely differing production forecasts and increased uncertainty. We have shown that the incorporation of seismic observations into the EnKF framework can significantly enhance reservoir simulations, decrease forecasting

  4. Eficacia de un programa de entrenamiento fisico y cognitivo basado en nuevas tecnologias en poblacion mayor saludable y con signos de deterioro cognitivo leve: Long Lasting Memories

    OpenAIRE

    González Palau, Fátima

    2013-01-01

    [ES] Introducción. Long Lasting Memories (LLM) es un proyecto internacional apoyado por la Unión Europea, que apunta a la validación de una plataforma TIC, que combine ejercicios cognitivos con la actividad física por medio de nuevas tecnologías. El objetivo del presente estudio es determinar la eficacia de la plataforma LLM en la mejoría de funciones cognitivas, síntomas depresivos y quejas subjetivas de memoria en adultos mayores saludables y con sin signos de deterioro cognitivo leve (DCL)...

  5. Calidad de vida relacionada con la salud en pacientes con diagnóstico de hipertensión arterial leve

    OpenAIRE

    Stefano Vinaccia; Japcy Margarita Quiceno; Ángela Gómez; Lina Marcela Montoya

    2007-01-01

    El propósito de esta investigación fue evaluar las dimensiones de la calidad de vida relacionadas con la salud en 282 pacientes con hipertensión arterial leve de la ciudad de Medellín, Colombia. Se utilizó el Cuestionario de Calidad de Vida en Hipertensión Arterial (CHAL). Los resultados evidenciaron un cierto deterioro en la calidad de vida de estos pacientes en lo que concierne al estado de ánimo y principalmente en sus manifestaciones somáticas.

  6. Evaluación del bienestar psicológico y estrategias de afrontamiento en padres con niños o adolescentes con retraso mental leve

    OpenAIRE

    Zapata, Analía; Bastida, Marisa; Quiroga, Adriana; Charra, Salomé; Leiva, Juan Manuel

    2013-01-01

    Tener un hijo con discapacidad intelectual supone una fuente de conflictos tanto para la dinámica familiar como para los propios adolescentes. Es probable que la familia tenga que reestructurarse para afrontar los niveles de estrés que puedan influir sobre el bienestar de sus miembros. Esta investigación evalúa el bienestar psicológico de los padres con un niño y/o adolescente entre 9 y 14 años con retraso mental leve, estrategias de afrontamiento y posibles relaciones entre estas variables. ...

  7. Associação dos níveis de BDNF com volume do hipocampo no comprometimento cognitivo leve e na doença de Alzheimer

    OpenAIRE

    Ericksen Mielle Borba

    2016-01-01

    Introdução: Perda de memória é um dos sintomas mais comuns em pacientes nos estágios iniciais da doença de Alzheimer; esses déficits são um reflexo do envolvimento da formação do hipocampo. O BDNF tem sido relacionado com a plasticidade do hipocampo. Neste sentido, as combinações de biomarcadores, como, por exemplo, a volumetria do hipocampo, pode apresentar um maior valor preditivo para diferenciar doença de Alzheimer do envelhecimento normal em pacientes com comprometimento cognitivo leve. ...

  8. The freshwater reservoir effect in radiocarbon dating

    DEFF Research Database (Denmark)

    Philippsen, Bente

    case studies will show the degree of variability of the freshwater reservoir effect over short and long timescales. Radiocarbon dating of recent water samples, aquatic plants and animals, shows that age differences of up to 2000 years can occur within one river. In the Limfjord, freshwater influence...... caused reservoir ages to vary between 250 and 700 years during the period 5400 BC - AD 700. Finally, I will discuss the implications of the freshwater reservoir effect for radiocarbon dating of Mesolithic pottery from inland sites of the Ertebølle culture in Northern Germany....

  9. Experiments with Interaction between the National Water Model and the Reservoir System Simulation Model: A Case Study of Russian River Basin

    Science.gov (United States)

    Kim, J.; Johnson, L.; Cifelli, R.; Chandra, C. V.; Gochis, D.; McCreight, J. L.; Yates, D. N.; Read, L.; Flowers, T.; Cosgrove, B.

    2017-12-01

    NOAA National Water Center (NWC) in partnership with the National Centers for Environmental Prediction (NCEP), the National Center for Atmospheric Research (NCAR) and other academic partners have produced operational hydrologic predictions for the nation using a new National Water Model (NWM) that is based on the community WRF-Hydro modeling system since the summer of 2016 (Gochis et al., 2015). The NWM produces a variety of hydrologic analysis and prediction products, including gridded fields of soil moisture, snowpack, shallow groundwater levels, inundated area depths, evapotranspiration as well as estimates of river flow and velocity for approximately 2.7 million river reaches. Also included in the NWM are representations for more than 1,200 reservoirs which are linked into the national channel network defined by the USGS NHDPlusv2.0 hydrography dataset. Despite the unprecedented spatial and temporal coverage of the NWM, many known deficiencies exist, including the representation of lakes and reservoirs. This study addresses the implementation of a reservoir assimilation scheme through coupling of a reservoir simulation model to represent the influence of managed flows. We examine the use of the reservoir operations to dynamically update lake/reservoir storage volume states, characterize flow characteristics of river reaches flowing into and out of lakes and reservoirs, and incorporate enhanced reservoir operating rules for the reservoir model options within the NWM. Model experiments focus on a pilot reservoir domain-Lake Mendocino, CA, and its contributing watershed, the East Fork Russian River. This reservoir is modeled using United States Army Corps of Engineers (USACE) HEC-ResSim developed for application to examine forecast informed reservoir operations (FIRO) in the Russian River basin.

  10. Gasbuggy reservoir evaluation - 1969 report

    International Nuclear Information System (INIS)

    Atkinson, C.H.; Ward, Don C.; Lemon, R.F.

    1970-01-01

    The December 10, 1967, Project Gasbuggy nuclear detonation followed the drilling and testing of two exploratory wells which confirmed reservoir characteristics and suitability of the site. Reentry and gas production testing of the explosive emplacement hole indicated a collapse chimney about 150 feet in diameter extending from the 4,240-foot detonation depth to about 3,900 feet, the top of the 300-foot-thick Pictured Cliffs gas sand. Production tests of the chimney well in the summer of 1968 and during the last 12 months have resulted in a cumulative production of 213 million cubic feet of hydrocarbons, and gas recovery in 20 years is estimated to be 900 million cubic feet, which would be an increase by a factor of at least 5 over estimated recovery from conventional field wells in this low permeability area. At the end of production tests the flow rate was 160,000 cubic feet per day, which is 6 to 7 times that of an average field well in the area. Data from reentry of a pre-shot test well and a new postshot well at distances from the detonation of 300 and 250 feet, respectively, indicate low productivity and consequently low permeability in any fractures at these locations. (author)

  11. A linearization of quantum channels

    Science.gov (United States)

    Crowder, Tanner

    2015-06-01

    Because the quantum channels form a compact, convex set, we can express any quantum channel as a convex combination of extremal channels. We give a Euclidean representation for the channels whose inverses are also valid channels; these are a subset of the extreme points. They form a compact, connected Lie group, and we calculate its Lie algebra. Lastly, we calculate a maximal torus for the group and provide a constructive approach to decomposing any invertible channel into a product of elementary channels.

  12. A Microchip-based Endothelium Mimic Utilizing Open Reservoirs for Cell Immobilization and Integrated Carbon Ink Microelectrodes for Detection

    Science.gov (United States)

    Hulvey, Matthew K; Martin, R. Scott

    2010-01-01

    This paper describes the fabrication and characterization of a microfluidic device that utilizes a reservoir-based approach for endothelial cell immobilization and integrated embedded carbon ink microelectrodes for the amperometric detection of extracellular nitric oxide (NO) release. The design utilizes a buffer channel to continuously introduce buffer or a plug of stimulant to the reservoir as well as a separate sampling channel that constantly withdraws buffer from the reservoir and over the microelectrode. A steel pin is used for both the fluidic connection to the sampling channel and to provide a quasi-reference electrode for the carbon ink microelectrode. Characterization of the device was performed using NO standards produced from a NONOate salt. Finally, NO release from a layer of immobilized endothelial cells was monitored and quantified using the system. This system holds promise as a means to electrochemically detect extracellular NO release from endothelial cells in either an array of reservoirs or concurrently with fluorescence-based intracellular NO measurements. PMID:18989663

  13. Volume 4: Characterization of representative reservoirs -- Gulf of Mexico field, U-8 reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Koperna, G.J. Jr.; Johnson, H.R. [BDM Federal, Inc., McLean, VA (United States); Salamy, S.P.; Reeves, T.K. [BDM-Oklahoma, Inc., Bartlesville, OK (United States); Sawyer, W.K. [Mathematical and Computer Services, Inc., Danville, VA (United States); Kimbrell, W.C.; Schenewerk, P.A. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Petroleum Engineering

    1998-07-01

    A reservoir study was performed using a publicly available black oil simulator to history match and predict the performance of a Gulf of Mexico reservoir. The first objective of this simulation study was to validate the Black Oil Applied Simulation Tool version three for personal computers (BOAST3-PC) model to ensure the integrity of the simulation runs. Once validation was completed, a field history match for the Gulf of Mexico U-8 oil reservoir was attempted. A verbal agreement was reached with the operator of this reservoir to blindcode the name and location of the reservoir. In return, the operator supplied data and assistance in regards to the technical aspects of the research. On the basis of the best history match, different secondary recovery techniques were simulated as a predictive study for enhancing the reservoir productivity.

  14. DESIGN OF PARABOLIC CHANNELS

    Directory of Open Access Journals (Sweden)

    A. K. Alibekov

    2015-01-01

    Full Text Available The dependence of the apparent location of the hydraulic parameters of parabolic channels in earthen channel and volume of dredging required in their design and construction, on the basis of conditions to ensure the stability of the slope at the maximum water flow rate. 

  15. Calcium channel blocker overdose

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002580.htm Calcium-channel blocker overdose To use the sharing features on this ... vary. However, the main ingredient is called a calcium-channel antagonist. It helps decrease the heart's pumping strength, which ...

  16. CHANNEL ESTIMATION TECHNIQUE

    DEFF Research Database (Denmark)

    2015-01-01

    the communication channel. The method further includes determining a sequence of second coefficient estimates of the communication channel based on a decomposition of the first coefficient estimates in a dictionary matrix and a sparse vector of the second coefficient estimates, the dictionary matrix including...

  17. Controls on the quality of Miocene reservoirs, southern Gulf of Mexico

    Science.gov (United States)

    Gutiérrez Paredes, Hilda Clarisa; Catuneanu, Octavian; Hernández Romano, Ulises

    2018-01-01

    An investigation was conducted to determine the main controls on the reservoir quality of the middle and upper Miocene sandstones in the southern Gulf of Mexico based on core descriptions, thin section petrography and petrophysical data; as well as to explore the possible link between the sequence stratigraphic framework, depositional facies and diagenetic alterations. The Miocene deep marine sandstones are attributed to the falling-stage, lowstand, and transgressive systems tracts. The middle Miocene falling-stage systems tract includes medium-to very fine-grained, and structureless sandstones deposited in channels and frontal splays, and muddy sandstones, deposited in lobes of debrites. The lowstand and transgressive systems tracts consist of medium-to very fine-grained massive and normally graded sandstones deposited in channel systems within frontal splay complexes. The upper Miocene falling-stage systems tract includes medium-to coarse-grained, structureless sandstones deposited in channel systems and frontal splay, as well as lobes of debrites formed by grain flows and hybrid-flow deposits. The lowstand and transgressive systems tracts include fine-grained sandstones deposited in overbank deposits. The results reveal that the depositional elements with the best reservoir quality are the frontal splays deposited during the falling-stage system tracts. The reservoir quality of the Miocene sandstones was controlled by a combination of depositional facies, sand composition and diagenetic factors (mainly compaction and calcite cementation). Sandstone texture, controlled primarily by depositional facies appears more important than sandstone composition in determining reservoir quality; and compaction was more important than cementation in porosity destruction. Compaction was stopped, when complete calcite cementation occurred.

  18. Zooplankton assemblage of Oyun Reservoir, Offa, Nigeria.

    Science.gov (United States)

    Mustapha, Moshood K

    2009-12-01

    The influence of physico-chemical properties of Oyun Reservoir, Offa, Nigeria (a shallow tropical African reservoir) on its zooplankton composition and abundance were investigated at three stations for two years between January 2002 and December 2003. Diversity is not high: only three groups of zooplankton were found: Rotifera with eight genera; and Cladocera and Copepoda with three genera each. Rotifera dominated numerically (71.02%), followed by Cladocera (16.45%) and Copepoda (12.53%). The zooplankton was more prevalent during the rainy season, and there were variations in the composition and abundance along the reservoir continuum. Factors such as temperature, nutrients, food availability, shape and hydrodynamics of the reservoir, as well as reproductive strategies of the organisms, strongly influence the generic composition and population density of zooplankton. Prevention of ecological deterioration of the water body would greatly should result in a more productive water body, rich in zooplankton and with better fisheries.

  19. Hydrological ensemble predictions for reservoir inflow management

    Science.gov (United States)

    Zalachori, Ioanna; Ramos, Maria-Helena; Garçon, Rémy; Gailhard, Joel

    2013-04-01

    Hydrologic forecasting is a topic of special importance for a variety of users with different purposes. It concerns operational hydrologists interested in forecasting hazardous events (eg., floods and droughts) for early warning and prevention, as well as planners and managers searching to optimize the management of water resources systems at different space-time scales. The general aim of this study is to investigate the benefits of using hydrological ensemble predictions for reservoir inflow management. Ensemble weather forecasts are used as input to a hydrologic forecasting model and daily ensemble streamflow forecasts are generated up to a lead time of 7 days. Forecasts are then integrated into a heuristic decision model for reservoir management procedures. Performance is evaluated in terms of potential gain in energy production. The sensitivity of the results to various reservoir characteristics and future streamflow scenarios is assessed. A set of 11 catchments in France is used to illustrate the added value of ensemble streamflow forecasts for reservoir management.

  20. Measuring the latent reservoir in vivo

    Science.gov (United States)

    Massanella, Marta; Richman, Douglas D.

    2016-01-01

    Current efforts toward achieving a cure for HIV are focused on developing strategies to eliminate latently infected CD4+ T cells, which represent the major barrier to virus eradication. Sensitive, precise, and practical assays that can reliably characterize and measure this HIV reservoir and can reliably measure the impact of a candidate treatment strategy are essential. PCR-based procedures for detecting integrated HIV DNA will overestimate the size of the reservoir by detecting replication-incompetent proviruses; however, viral outgrowth assays underestimate the size of the reservoir. Here, we describe the attributes and limitations of current procedures for measuring the HIV reservoir. Characterizing their relative merits will require rigorous evaluation of their performance characteristics (sensitivity, specificity, reproducibility, etc.) and their relationship to the results of clinical studies. PMID:26829625

  1. Assembling evidence for identifying reservoirs of infection

    Science.gov (United States)

    Mafalda, Viana; Rebecca, Mancy; Roman, Biek; Sarah, Cleaveland; Cross, Paul C.; James O, Lloyd-Smith; Daniel T, Haydon

    2014-01-01

    Many pathogens persist in multihost systems, making the identification of infection reservoirs crucial for devising effective interventions. Here, we present a conceptual framework for classifying patterns of incidence and prevalence, and review recent scientific advances that allow us to study and manage reservoirs simultaneously. We argue that interventions can have a crucial role in enriching our mechanistic understanding of how reservoirs function and should be embedded as quasi-experimental studies in adaptive management frameworks. Single approaches to the study of reservoirs are unlikely to generate conclusive insights whereas the formal integration of data and methodologies, involving interventions, pathogen genetics, and contemporary surveillance techniques, promises to open up new opportunities to advance understanding of complex multihost systems.

  2. The glaciogenic reservoir analogue studies project (GRASP)

    DEFF Research Database (Denmark)

    Moscariello, A.; Moreau, Julien; Vegt, P. van der

    Tunnel galleys are common features in Palaeozoic glacigenic succession in North Afrcica and Middle East and they are amongst the most challenging target for hydrocarbon exploration and developing drilling in these regions. Similarly, these buried valleys form important groundwater reservoirs...

  3. NYC Reservoirs Watershed Areas (HUC 12)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This NYC Reservoirs Watershed Areas (HUC 12) GIS layer was derived from the 12-Digit National Watershed Boundary Database (WBD) at 1:24,000 for EPA Region 2 and...

  4. Study of the relation between soil use, vegetation coverage, and the discharge of sediments from artificial reservoirs using MSS/LANDSAT images. Example: The Tres Marias reservoir and its supply basin

    Science.gov (United States)

    Dejesusparada, N. (Principal Investigator); Sausen, T. M.

    1981-01-01

    The land use and types of vegetation in the region of the upper Sao Francisco River, Brazil, are identified. This region comprises the supply basin of the Tres Marias reservoir. Imagery from channels 5 and 7 of the LANDSAT multispectral band scanner during wet and rainy seasons and ground truth data were employed to characterize and map the vegetation, land use, and sedimentary discharges from the reservoir. Agricultural and reforested lands, meadows, and forests are identified. Changes in land use due to human activity are demonstrated.

  5. Athermalized channeled spectropolarimeter enhancement.

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Julia Craven; Way, Brandyn Michael; Mercier, Jeffrey Alan; Hunt, Jeffery P.

    2013-09-01

    Channeled spectropolarimetry can measure the complete polarization state of light as a function of wavelength. Typically, a channeled spectropolarimeter uses high order retarders made of uniaxial crystal to amplitude modulate the measured spectrum with the spectrally-dependent Stokes polarization information. A primary limitation of conventional channeled spectropolarimeters is related to the thermal variability of the retarders. Thermal variation often forces frequent system recalibration, particularly for field deployed systems. However, implementing thermally stable retarders, made of biaxial crystal, results in an athermal channeled spectropolarimeter that relieves the need for frequent recalibration. This report presents experimental results for an anthermalized channeled spectropolarimeter prototype produced using potassium titanyl phosphate. The results of this prototype are compared to the current thermal stabilization state of the art. Finally, the application of the technique to the thermal infrared is studied, and the athermalization concept is applied to an infrared imaging spectropolarimeter design.

  6. Cardiac potassium channel subtypes

    DEFF Research Database (Denmark)

    Schmitt, Nicole; Grunnet, Morten; Olesen, Søren-Peter

    2014-01-01

    . The underlying posttranscriptional and posttranslational remodeling of the individual K(+) channels changes their activity and significance relative to each other, and they must be viewed together to understand their role in keeping a stable heart rhythm, also under menacing conditions like attacks of reentry......About 10 distinct potassium channels in the heart are involved in shaping the action potential. Some of the K(+) channels are primarily responsible for early repolarization, whereas others drive late repolarization and still others are open throughout the cardiac cycle. Three main K(+) channels...... that they could constitute targets for new pharmacological treatment of atrial fibrillation. The interplay between the different K(+) channel subtypes in both atria and ventricle is dynamic, and a significant up- and downregulation occurs in disease states such as atrial fibrillation or heart failure...

  7. Muon cooling channels

    CERN Document Server

    Eberhard-K-Kei

    2003-01-01

    A procedure uses the equations that govern ionization cooling, and leads to the most important parameters of a muon cooling channel that achieves assumed performance parameters. First, purely transverse cooling is considered, followed by both transverse and longitudinal cooling in quadrupole and solenoid channels. Similarities and differences in the results are discussed in detail, and a common notation is developed. Procedure and notation are applied to a few published cooling channels. The parameters of the cooling channels are derived step by step, starting from assumed values of the initial, final and equilibrium emittances, both transverse and longitudinal, the length of the cooling channel, and the material properties of the absorber. The results obtained include cooling lengths and partition numbers, amplitude functions and limits on the dispersion at the absorber, length, aperture and spacing of the absorber, parameters of the RF system that achieve the longitudinal amplitude function and bucket area ...

  8. Destratification of an impounding reservoir using compressed air??case of Mudi reservoir, Blantyre, Malawi

    Science.gov (United States)

    Chipofya, V. H.; Matapa, E. J.

    This paper reviews the operational and cost effectiveness of a compressed air destratification system that was installed in the Mudi reservoir for destratifying the reservoir. Mudi reservoir is a raw water source for the Blantyre Water Board. It has a capacity of 1,400,000 cubic metres. The reservoir is 15.3 m deep at top water level. In the absence of any artificial circulation of air, the reservoir stratifies into two layers. There is a warm epilimnion in the top 3 m of the reservoir, with temperatures ranging from 23 to 26 °C. There is prolific algal growth in this layer. The bottom layer has much lower temperatures, and is oxygen deficient. Under such anaerobic conditions, ammonia, sulphides, iron and manganese are released from the sediments of the reservoir. As a result of nutrient inflow from the catchments, coupled with tropical ambient temperatures, the reservoir is most times infested with blue-green algae. This results into water treatment problems in respect of taste and odour and iron and manganese soluble salts. To abate such problems, air is artificially circulated in the reservoir, near the intake tower, through a perforated pipe that is connected to an electrically driven compressor. This causes artificial circulation of water in the hypolimnion region of the reservoir. As a result of this circulation, a hostile environment that inhibits the propagation of algae is created. Dissolved oxygen and temperature profiles are practically uniform from top to bottom of reservoir. Concentrations of iron and manganese soluble salts are much reduced at any of the draw-off points available for the water treatment process. The paper concludes by highlighting the significant cost savings in water treatment that are accrued from the use of compressed air destratification in impounding water storage reservoirs for the control of algae and other chemical pollutants.

  9. Installation of a Devonian Shale Reservoir Testing Facility and acquisition of reservoir property measurements

    Energy Technology Data Exchange (ETDEWEB)

    Locke, C.D.; Salamy, S.P.

    1991-09-01

    In October, a contract was awarded for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property measurements from wells in the Michigan, Illinois, and Appalachian Basins. Geologic and engineering data collected through this project will provide a better understanding of the mechanisms and conditions controlling shale gas production. This report summarizes the results obtained from the various testing procedures used at each wellsite and the activities conducted at the Reservoir Testing Facility.

  10. Installation of a Devonian Shale Reservoir Testing Facility and acquisition of reservoir property measurements. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Locke, C.D.; Salamy, S.P.

    1991-09-01

    In October, a contract was awarded for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property measurements from wells in the Michigan, Illinois, and Appalachian Basins. Geologic and engineering data collected through this project will provide a better understanding of the mechanisms and conditions controlling shale gas production. This report summarizes the results obtained from the various testing procedures used at each wellsite and the activities conducted at the Reservoir Testing Facility.

  11. Flow of a stream through a reservoir

    International Nuclear Information System (INIS)

    Sauerwein, K.

    1967-01-01

    If a reservoir is fed from a single source, which may not always be pure, the extent to which the inflowing stream mixes with the water in the reservoir is important for the quality of the water supplied by the reservoir. This question was investigated at the Lingese Reservoir, containing between one and two million cubic metres of water, in the Bergisches Land (North Rhine-Westphalia). The investigation was carried out at four different seasons so that the varying effects of the stream-water temperatures could be studied in relation to the temperature of the reservoir water. The stream was radioactively labelled at the point of inflow into the reservoir, and its flow through the reservoir was measured in length and depth from boats, by means of 1-m-long Geiger counters. In two cases the radioactivity of the outflowing water was also measured at fixed points. A considerable variety of intermixing phenomena were observed; these were mainly of limnological interest. The results of four experiments corresponding to the four different seasons are described in detail. They were as follows: (1) The mid-October experiment where the stream, with a temperature of 8.0 deg. C, was a good 5 deg. C colder than the water of the reservoir, whose temperature was almost uniform, ranging from 13.2 deg. C at the bed to 13.6 deg. C at the surface. (2) The spring experiment (second half of March), when the stream temperature was only 0.3 deg. C below that of the reservoir surface (7.8 deg. C), while the temperature of the bed was 5.8 deg. C. (3) The winter experiment (early December) where at first the temperature of the stream was approximately the same as that of the surface so that, once again, the stream at first flowed 1/2 - 1 m below the surface. During the almost wind-free night a sudden fall in temperature occurred, and the air temperature dropped from 0 deg. C to -12 deg. C. (4) The summer experiment (end of July to mid-August) when the stream was nearly 1 deg. C colder than

  12. Oil reservoir properties estimation using neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Toomarian, N.B. [California Inst. of Tech., Pasadena, CA (United States); Barhen, J.; Glover, C.W. [Oak Ridge National Lab., TN (United States). Center for Engineering Systems Advanced Research; Aminzadeh, F. [UNOCAL Corp., Sugarland, TX (United States)

    1997-02-01

    This paper investigates the applicability as well as the accuracy of artificial neural networks for estimating specific parameters that describe reservoir properties based on seismic data. This approach relies on JPL`s adjoint operators general purpose neural network code to determine the best suited architecture. The authors believe that results presented in this work demonstrate that artificial neural networks produce surprisingly accurate estimates of the reservoir parameters.

  13. Evaluation of an Empirical Reservoir Shape Function to Define Sediment Distributions in Small Reservoirs

    Directory of Open Access Journals (Sweden)

    Bogusław Michalec

    2015-08-01

    Full Text Available Understanding and defining the spatial distribution of sediment deposited in reservoirs is essential not only at the design stage but also during the operation. The majority of research concerns the distribution of sediment deposition in medium and large water reservoirs. Most empirical methods do not provide satisfactory results when applied to the determination of sediment deposition in small reservoirs. Small reservoir’s volumes do not exceed 5 × 106 m3 and their capacity-inflow ratio is less than 10%. Long-term silting measurements of three small reservoirs were used to evaluate the method described by Rahmanian and Banihashemi for predicting sediment distributions in small reservoirs. Rahmanian and Banihashemi stated that their model of distribution of sediment deposition in water reservoir works well for a long duration operation. In the presented study, the silting rate was used in order to determine the long duration operation. Silting rate is a quotient of volume of the sediment deposited in the reservoir and its original volume. It was stated that when the silting rate had reached 50%, the sediment deposition in the reservoir may be described by an empirical reservoir depth shape function (RDSF.

  14. Application of integrated reservoir management and reservoir characterization to optimize infill drilling

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    This project has used a multi-disciplinary approach employing geology, geophysics, and engineering to conduct advanced reservoir characterization and management activities to design and implement an optimized infill drilling program at the North Robertson (Clearfork) Unit in Gaines County, Texas. The activities during the first Budget Period consisted of developing an integrated reservoir description from geological, engineering, and geostatistical studies, and using this description for reservoir flow simulation. Specific reservoir management activities were identified and tested. The geologically targeted infill drilling program currently being implemented is a result of this work. A significant contribution of this project is to demonstrate the use of cost-effective reservoir characterization and management tools that will be helpful to both independent and major operators for the optimal development of heterogeneous, low permeability shallow-shelf carbonate (SSC) reservoirs. The techniques that are outlined for the formulation of an integrated reservoir description apply to all oil and gas reservoirs, but are specifically tailored for use in the heterogeneous, low permeability carbonate reservoirs of West Texas.

  15. A reservoir operating method for riverine ecosystem protection, reservoir sedimentation control and water supply

    Science.gov (United States)

    Yin, Xin-An; Yang, Zhi-Feng; Petts, Geoffrey E.; Kondolf, G. Mathias

    2014-05-01

    Riverine ecosystem protection requires the maintenance of natural flow and sediment regimes downstream from dams. In reservoir management schedules this requirement should be integrated with sedimentation control and human water supply. However, traditional eco-friendly reservoir operating methods have usually only considered the natural flow regime. This paper seeks to develop a reservoir operating method that accounts for both the natural flow and sediment regimes as well as optimizing the water supply allocations. Herein, reservoir water level (RWL), sediment-occupied ratio of reservoir volume (SOR) and rate of change of SOR (RCSOR) are adopted as three triggers of a drawdown-flushing-based sediment management policy. Two different groups of reservoir operating rule curves (RORCs) are designed for sediment-flushing and non-sediment-flushing years, and the three triggers, RWL, SOR and RCSOR, are used to change the “static” RORCs to “dynamic” ones. The approach is applied to the Wangkuai Reservoir, China to test its effectiveness. This shows that the approach can improve the flexibility of reservoir operators to balance the reservoir management, water supply management and the flow and sediment needs of the downstream riverine ecosystem.

  16. Generation of reservoir models on flexible meshes; Generation de modeles de reservoir sur maillage flexible

    Energy Technology Data Exchange (ETDEWEB)

    Ricard, L.

    2005-12-15

    The high level geo-statistic description of the subsurface are often far too detailed for use in routine flow simulators. To make flow simulations tractable, the number of grid blocks has to be reduced: an approximation, still relevant with flow description, is necessary. In this work, we place the emphasis on the scaling procedure from the fine scale model to the multi-scale reservoir model. Two main problems appear: Near wells, faults and channels, the volume of flexible cells may be less than fine ones, so we need to solve a down-scaling problem; Far from these regions, the volume of cells are bigger than fine ones so we need to solve an up-scaling problem. In this work, research has been done on each of these three areas: down-scaling, up-scaling and fluid flow simulation. For each of these subjects, a review, some news improvements and comparative study are proposed. The proposed down-scaling method is build to be compatible with existing data integration methods. The comparative study shows that empirical methods are not enough accurate to solve the problem. Concerning the up-scaling step, the proposed approach is based on an existing method: the perturbed boundary conditions. An extension to unstructured mesh is developed for the inter-cell permeability tensor. The comparative study shows that numerical methods are not always as accurate as expected and the empirical model can be sufficient in lot of cases. A new approach to single-phase fluid flow simulation is developed. This approach can handle with full tensorial permeability fields with source or sink terms.(author)

  17. Water in chalk reservoirs: 'friend or foe?'

    International Nuclear Information System (INIS)

    Hjuler, Morten Leth

    2004-01-01

    Most of the petroleum fields in the Norwegian sector of the North Sea are sandstone reservoirs; the oil and gas are trapped in different species of sandstone. But the Ekofisk Field is a chalk reservoir, which really challenges the operator companies. When oil is produced from chalk reservoirs, water usually gets in and the reservoir subsides. The subsidence may be expensive for the oil companies or be used to advantage by increasing the recovery rate. Since 60 per cent of the world's petroleum reserves are located in carbonate reservoirs, it is important to understand what happens as oil and gas are pumped out. Comprehensive studies at the Department of Petroleum Technology and Applied Geophysics at Stavanger University College in Norway show that the mechanical properties of chalk are considerably altered when the pores in the rock become saturated with oil/gas or water under different stress conditions. The processes are extremely complex. The article also maintains that the effects of injecting carbon dioxide from gas power plants into petroleum reservoirs should be carefully studied before this is done extensively

  18. The pollution of the 'iron gate' reservoir

    International Nuclear Information System (INIS)

    Babic-Mladenovic, M.; Varga, S; Popovic, L.; Damjanovic, M.

    2002-01-01

    The paper presents the characteristics of the Iron Gate I (the Djerdap) Water Power and Navigational System, one of the largest in Europe (completed in 1972 by joint efforts of Yugoslavia and Romania). In this paper the attention is devoted to review of the sediment monitoring program and impacts of reservoir sedimentation, as well as to the investigations of water and sediment quality. Special consideration is paid to the issue of sediment pollution research needs. Namely, the hot spot of the 'Iron Gate' sedimentation represents a scarcely known pollution of sediment deposits. The present pollution probably is considerable, since the 'Iron Gate' reservoir drains about 577000 km 2 , with over 80 million inhabitants, and developed municipal and industrial infrastructure. Therefore, in the thirty-year reservoir life various types of sediment-bound pollutants entered and deposited within it. Especially severe incidents happened during 1999 (as a result of NATO bombing campaign) and 2000 (two accidental pollutions in the Tisza river catchment). The study of the 'Iron Gate' reservoir pollution should be prepared in order to enlighten the present state of reservoir sedimentation and pollution. The main objectives of the study are to enhance the government and public awareness of the present environmental state of the 'Iron Gate' reservoir and to serve as a baseline for all future actions. (author)

  19. Trombose de veia renal, doença de depósito de cadeias leves e nefropatia dos cilindros em paciente com mieloma múltiplo

    Directory of Open Access Journals (Sweden)

    Vilma Takayasu

    2012-08-01

    Full Text Available Mulher de 56 anos, hipertensa há 16 anos em tratamento, apresenta quadro de dor torácica e dispnéia há 3 dias. A investigação laboratorial demonstrou insuficiência renalaguda com indicação de hemodiálise. Após diálise, apesar de melhora clínico-laboratorial, apresentou fibrilação ventricular e parada cardiorrespiratória revertidas. Evoluiu oligúrica, sem déficits neurológicos. Foi iniciada investigação laboratorial para mieloma múltiplo que demonstrou hipogamaglobulinemia sem pico monoclonal na eletroforese de proteínas. Durante a investigação a paciente apresentou novo episódio de fibrilaçãoventricular e óbito. A autópsia demonstrou trombose de veia renal esquerda, mieloma múltiplo plasmacítico com acometimento de medula óssea, nefropatia por depósitodifuso de cadeias leves kappa glomerular e tubular e nefropatia dos cilindros do mieloma.Este caso ilustra uma associação incomum entre nefropatia dos cilindros, nefropatia por depósito de cadeias leves e trombose de veia renal em paciente com mieloma múltiplo e insuficiência renal aguda.

  20. Aplicación de nuevas tecnologías en personas mayores con trastorno cognitivo leve-moderado desde la Terapia Ocupacional

    Directory of Open Access Journals (Sweden)

    María del Carmen Rodríguez Martínez

    2017-05-01

    Full Text Available Esta revisión bibliográfica pretende ofrecer una visión de las posibilidades que ofrecen las nuevas tecnologías a personas mayores con deterioro cognitivo leve-moderado para retardar o frenar los síntomas de deterioro cognitivo. Actualmente, las nuevas tecnologías de la información y la comunicación tienen mucho protagonismo y se han convertido en una herramienta con mucho potencial para este tipo de personas. Para ello, se han  analizado una serie de estudios sobre el uso de las nuevas tecnologías en personas mayores con trastornos cognitivos con el fin de ofrecer una visión más clara sobre los datos obtenidos hasta el día de hoy respecto a este campo de investigación en Terapia Ocupacional. Se seleccionaron un total de 204 artículos, tras un proceso de duplicación y tras pasar diferentes herramientas de calidad, quedaron un total de 7 artículos. Los resultados encontrados indican que las nuevas tecnologías contribuyen a disminuir algunos síntomas asociados a la enfermedad, como la ansiedad y la depresión, mejorando además ciertas funciones cognitivas en personas que tienen un deterioro cognitivo leve-moderado, siendo importante combinarlas con las terapias tradicionales.

  1. Modelling of Hydropower Reservoir Variables for Energy Generation ...

    African Journals Online (AJOL)

    Efficient management of hydropower reservoir can only be realized when there is sufficient understanding of interactions existing between reservoir variables and energy generation. Reservoir inflow, storage, reservoir elevation, turbine release, net generating had, plant use coefficient, tail race level and evaporation losses ...

  2. Marine and fluvial facies modelling at petroleum reservoir scale; Modelisation des heterogeneites lithologiques a l'echelle du reservoir petrolier en milieu marin et fluviatile

    Energy Technology Data Exchange (ETDEWEB)

    Leflon, B.

    2005-10-15

    When modelling a petroleum reservoir, well data are very useful to model properties at a sub-seismic scale. Petrophysical properties like porosity or permeability are linked to the rock-type. Two methods based on well data have been developed to model facies. The first one is used to model marine carbonates deposits. The geometry of sedimentary layers is modelled through a special parameterization of the reservoir similar to Wheeler space. The time parameter is defined along the well paths thanks to correlations. The layer thickness is then extrapolated between wells. A given relationship between facies and bathymetry of sedimentation makes it possible to compute bathymetry along the well paths. Bathymetry is then extrapolated from wells and a reference map using the concept of accommodation. The model created this way is stratigraphically consistent. Facies simulation can then be constrained by the computed bathymetry. The second method describes a novel approach to fluvial reservoirs modelling. The core of the method lies in the association of a fairway with the channels to be simulated. Fairways are positioned so that all data are taken in account; they can be stochastic if unknown or explicitly entered if identified on seismic data. A potential field is defined within the fairway. Specifying a transfer function to map this potential field to thickness results in generating a channel inside the fairway. A residual component is stochastically simulated and added to the potential field creating realistic channel geometries. Conditioning to well data is obtained by applying the inverse transfer function at the data location to derive thickness values that will constrain the simulation of residuals. (author)

  3. Study on Transfer Rules of Coal Reservoir Pressure Drop Based on Coalbed Methane Well Drainage Experiments

    Science.gov (United States)

    Yuhang, X.

    2017-12-01

    A pumping test was carried out to explore the transfer rules of pressure drop in coal reservoir during the drainage. The experiment was divided into three stages. In the first stage, the pump displacement of 3m3/h was used to reduce the bottom hole flowing pressure and stopped until the continuous gas phase was produced; Undertaking the first stage, in the second stage, when the gas phase was continuously produced, the pump was stopped immediately. As the bottom hole flowing pressure going up without gas phase, pumping started again for a week. In the third stage ,the well pumping was carried out at the bottom hole pressure drop rate of 30Kpa/d after two months' recovery. Combined with the data of regional geology and fractured well, taking the characteristics of macroscopic coal rocks, development of pore and fracture in coal and isothermal adsorption test as the background, the features of reservoir output in each stage of the experiment were analyzed and compared, and then the transfer rules of pressure drop contained in the differences of the output was studied further. In the first and third stage of the experiment, the output of liquid phase was much larger than the space volume of coal reservoir pore and fracture in the range of 100m2. In the second stage, the output of the continuous gas phase appeared around 0.7Mpa when the continuous gas phase appears below the critical desorption pressure of 0.25Mpa during the whole experiment. The results indicate that, the transfer of pressure drop in the coal reservoir of this well is mainly horizontal, and the liquid phase produced in the reservoir mainly comes from the recharge of the reservoir at the far end of the relative high pressure area; the adsorption space of coalbed methane in the coal matrix as well as the main migration channel of fluid in the reservoir doesn't belong to the same pressure system and there exists the communication barrier between them. In addition, the increasing of the effective stress

  4. Channel, floodplain, and wetland responses to floods and overbank sedimentation, 1846-2006, Halfway Creek Marsh, Upper Mississippi Valley, Wisconsin

    Science.gov (United States)

    Fitzpatrick, F.A.; Knox, J.C.; Schubauer-Berigan, J. P.

    2009-01-01

    Conversion of upland forest and prairie vegetation to agricultural land uses, following Euro-American settlement in the Upper Mississippi River System, led to accelerated runoff and soil erosion that subsequently transformed channels, floodplains, and wetlands on bottomlands. Halfway Creek Marsh, at the junction of Halfway Creek and the Mississippi River on Wisconsin's western border, is representative of such historical transformation. This marsh became the focus of a 2005-2006 investigation by scientists from the U.S. Geological Survey, the University of Wisconsin- Madison, and the U.S. Environmental Protection Agency, who used an understanding of the historical transformation to help managers identify possible restoration alternatives for Halfway Creek Marsh. Field-scale topographic surveys and sediment cores provided data for reconstructing patterns and rates of historical overbank sedimentation in the marsh. Information culled from historical maps, aerial photographs, General Land Offi ce Survey notes, and other historical documents helped establish the timing of anthropogenic disturbances and document changes in channel patterns. Major human disturbances, in addition to agricultural land uses, included railroad and road building, construction of artifi cial levees, drainage alterations, and repeated dam failures associated with large floods. A volume of approximately 1,400,000 m3, involving up to 2 m of sandy historical overbank deposition, is stored through the upper and lower marshes and along the adjacent margins of Halfway Creek and its principal tributary, Sand Lake Coulee. The estimated overbank sedimentation rate for the entire marsh is ??3,000 m3 yr-1 for the recent period 1994-2006. In spite of reduced surface runoff and soil erosion in recent years, this recent sedimentation rate still exceeds by ??4 times the early settlement (1846-1885) rate of 700 m3 yr-1, when anthropogenic acceleration of upland surface runoff and soil erosion was beginning

  5. Lithofacies and associated reservoir properties co-simulations constraint by seismic data; Cosimulations de lithofacies et de proprietes reservoirs associees contraintes par les donnees sismiques

    Energy Technology Data Exchange (ETDEWEB)

    Fichtl, P.

    1998-01-19

    Integration of data different sources and nature leads to more accurate reservoir models, useful for controlling fluid and assessing final uncertainties. In this frame, this thesis presents a new technique for co-simulating in 3D two high resolution properties - one categorical, one continuous - conditionally to well information and under the constraint of seismic data. This technique could be applied to simulate lithofacies and related reservoir properties like acoustic impedances or porosities. The proposed algorithm combines a non-parametric approach for the categorical variable and a parametric approach for the continuous variable through a sequential co-simulation. The co-simulation process is divided in two steps: in the first step, the lithofacies is co-simulated with the seismic information by a sequential indicator co-simulation with co-kriging and, in the second step, the reservoir property of interest is simulated from the previously co-simulated lithofacies using sequential Gaussian (co- )simulation or P-field simulation. A validation study on a synthetic but realistic model shows that this technique provides alternative models of lithofacies and associated high resolution acoustic impedances consistent with the seismic data. The seismic information constraining the co-simulations contributes to reduce the uncertainties for the lithofacies distribution at the reservoir level. In some case, a Markov co-regionalization model can be used for simplifying the inference and modelling of the cross-covariances; finally, the co-simulation algorithm was applied to a 3D real case study with objective the joint numerical modelling of lithofacies and porosity in a fluvial channel reservoir. (author) 88 refs.

  6. Coherifying quantum channels

    Science.gov (United States)

    Korzekwa, Kamil; Czachórski, Stanisław; Puchała, Zbigniew; Życzkowski, Karol

    2018-04-01

    Is it always possible to explain random stochastic transitions between states of a finite-dimensional system as arising from the deterministic quantum evolution of the system? If not, then what is the minimal amount of randomness required by quantum theory to explain a given stochastic process? Here, we address this problem by studying possible coherifications of a quantum channel Φ, i.e., we look for channels {{{Φ }}}{ \\mathcal C } that induce the same classical transitions T, but are ‘more coherent’. To quantify the coherence of a channel Φ we measure the coherence of the corresponding Jamiołkowski state J Φ. We show that the classical transition matrix T can be coherified to reversible unitary dynamics if and only if T is unistochastic. Otherwise the Jamiołkowski state {J}{{Φ }}{ \\mathcal C } of the optimally coherified channel is mixed, and the dynamics must necessarily be irreversible. To assess the extent to which an optimal process {{{Φ }}}{ \\mathcal C } is indeterministic we find explicit bounds on the entropy and purity of {J}{{Φ }}{ \\mathcal C }, and relate the latter to the unitarity of {{{Φ }}}{ \\mathcal C }. We also find optimal coherifications for several classes of channels, including all one-qubit channels. Finally, we provide a non-optimal coherification procedure that works for an arbitrary channel Φ and reduces its rank (the minimal number of required Kraus operators) from {d}2 to d.

  7. Impacts of channel deposition on the risk of flooding in a watershed

    Science.gov (United States)

    Ting-Yue, Hong; Chia-Ling, Chang

    2017-04-01

    Taiwan is located in East Asian where is always hit by typhoons. Typhoons usually bring huge amounts of rainfall and result in the problems of channel deposition. Deposition influences the functions of channel and increases the risk of flooding. The Luliao Reservoir Watershed is the case area in this study. It is the major water source for agricultural activity and domestic use. The objective of this study is to assess the possible impacts of channel deposition on the watershed environment. This study applies the Storm Water Management Model (SWMM) to predict the hydrologic responses and evaluate the risk of flooding. The results show that the decrease of cross section induced by deposition in a channel may increase the risk of flooding and impact the safety of watershed environment. Therefore, canal desilting is important in channel regulation. The discussion and analysis can be useful references for channel regulation.

  8. Cellular ion channel-pump system modeling using switched stochastic differential equations.

    Science.gov (United States)

    Weaver, Jeffrey

    2007-01-01

    This paper identifies a multidimensional random switched process model of a neuron with embedded Ca++ ion channel and pump molecules adiabatically interacting based on local ion concentrations near the cell membrane. The model interprets known physiology of the channels as a coupled set of switched random processes and derives mechanical equations based on concentration flow among different states of the system. Rapid changes to channel barrier energies occurring during channel opening and closing transitions are modeled as another degree of freedom commutating the state of the overall system. An ion reservoir model is used as the primary tool to incorporate stochastic effects in channel operation. The complete model is analyzed numerically and then the equations are used to motivate a stochastic model for closed state dwell times. The result is compared against expected results of a leaky-integrator and known single-channel histograms.

  9. Gross greenhouse gas fluxes from hydro-power reservoir compared to thermo-power plants

    International Nuclear Information System (INIS)

    Santos, Marco Aurelio dos; Pinguelli Rosa, Luiz; Sikar, Bohdan; Sikar, Elizabeth; Santos, Ednaldo Oliveira dos

    2006-01-01

    This paper presents the findings of gross carbon dioxide and methane emissions measurements in several Brazilian hydro-reservoirs, compared to thermo power generation. The term 'gross emissions' means gas flux measurements from the reservoir surface without natural pre-impoundment emissions by natural bodies such as the river channel, seasonal flooding and terrestrial ecosystems. The net emissions result from deducting pre-existing emissions by the reservoir. A power dam emits biogenic gases such as CO 2 and CH 4 . However, studies comparing gas emissions (gross emissions) from the reservoir surface with emissions by thermo-power generation technologies show that the hydro-based option presents better results in most cases analyzed. In this study, measurements were carried in the Miranda, Barra Bonita, Segredo, Tres Marias, Xingo, and Samuel and Tucurui reservoirs, located in two different climatological regimes. Additional data were used here from measurements taken at the Itaipu and Serra da Mesa reservoirs. Comparisons were also made between emissions from hydro-power plants and their thermo-based equivalents. Bearing in mind that the estimated values for hydro-power plants include emissions that are not totally anthropogenic, the hydro-power plants studied generally posted lower emissions than their equivalent thermo-based counterparts. Hydro-power complexes with greater power densities (capacity/area flooded-W/m 2 ), such as Itaipu, Xingo, Segredo and Miranda, have the best performance, well above thermo-power plants using state-of-the-art technology: combined cycle fueled by natural gas, with 50% efficiency. On the other hand, some hydro-power complexes with low-power density perform only slightly better or even worse than their thermo-power counterparts

  10. Evaluation channel performance in multichannel environments

    NARCIS (Netherlands)

    Gensler, S.; Dekimpe, M.; Skiera, B.

    2007-01-01

    Evaluating channel performance is crucial for actively managing multiple sales channels, and requires understanding the customers' channel preferences. Two key components of channel performance are (i) the existing customers' intrinsic loyalty to a particular channel and (ii) the channel's ability

  11. An environmental data base for all Hydro-Quebec reservoirs

    International Nuclear Information System (INIS)

    Demers, C.

    1988-01-01

    Hydro-Quebec has created two management positions specifically for reservoirs, namely Reservoir Ecology Advisor and Reservoir Management Advisor. To assist management decisions, a means was required of bringing together all existing environmental information for each reservoir operated by Hydro-Quebec, including storage reservoirs, auxiliary reservoirs and forebays. A relational database using Reflex software was developed on a network of Macintosh computers. The database contains five blocks of information: general information, and physical, physiochemical, biologic and socioeconomic characteristics for each reservoir. Data will be collected on over 100 sites, and the tool will form the basis for developing a medium-range study program on reservoir ecology. The program must take into account the physical, biological and socioeconomic aspects of the environment, as well as the concerns of management personnel operating the reservoirs, the local population, reservoir users, and various government departments. 2 figs

  12. Transposition of a Process-Based Model, Flumy: from Meandering Fluvial Systems to Channelized Turbidite Systems

    Science.gov (United States)

    Lemay, M.; Cojan, I.; Rivoirard, J.; Grimaud, J. L.; Ors, F.

    2017-12-01

    Channelized turbidite systems are among the most important hydrocarbon reservoirs. Yet building realistic turbidite reservoir models is still a challenge. Flumy has been firstly developed to simulate the long-term evolution of aggrading meandering fluvial systems in order to build facies reservoir models. In this study, Flumy has been transposed to channelized turbidite systems. The channel migration linear model of Imran et al. (1999) dedicated to subaqueous flows has been implemented. The whole model has been calibrated taking into account the differences on channel morphology, avulsion frequency, and aggradation and migration rates. This calibration and the comparison of the model to natural systems rely on: i) the channel planform morphology characterized by the meander wavelength, amplitude, and sinuosity; ii) the channel trajectory and the resulting stratigraphic architecture described using Jobe et al. (2016) indexes. Flumy succeeds in reproducing turbidite channel planform morphology as shown by the mean sinuosity of 1.7, the wavelength to width and amplitude to width ratios around 4 and 1 respectively. First-order meander architecture, characterized by the ratios meander belt width versus channel width, meander belt thickness versus channel depth, and the deduced stratigraphic mobility number (the ratio between lateral versus vertical channel displacements), is also well reproduced: 2.5, 3.8, and 0.6 respectively. Both lateral and downstream channel normalized migrations are around 3.5 times lower than in fluvial systems. All these values are absolutely coherent with the observations. In the other hand, the channel trajectory observed on seismic cross sections (hockey stick geometry) is not fully reproduced: the local stratigraphic mobility number is divided upward by 3 whereas up to 10 is expected. This behavior is generally explained in the literature by an increasing aggradation rate through time and/or flow stripping at outer bend that decreases

  13. Fractional channel multichannel analyzer

    Science.gov (United States)

    Brackenbush, L.W.; Anderson, G.A.

    1994-08-23

    A multichannel analyzer incorporating the features of the present invention obtains the effect of fractional channels thus greatly reducing the number of actual channels necessary to record complex line spectra. This is accomplished by using an analog-to-digital converter in the asynchronous mode, i.e., the gate pulse from the pulse height-to-pulse width converter is not synchronized with the signal from a clock oscillator. This saves power and reduces the number of components required on the board to achieve the effect of radically expanding the number of channels without changing the circuit board. 9 figs.

  14. Cl- channels in apoptosis

    DEFF Research Database (Denmark)

    Wanitchakool, Podchanart; Ousingsawat, Jiraporn; Sirianant, Lalida

    2016-01-01

    A remarkable feature of apoptosis is the initial massive cell shrinkage, which requires opening of ion channels to allow release of K(+), Cl(-), and organic osmolytes to drive osmotic water movement and cell shrinkage. This article focuses on the role of the Cl(-) channels LRRC8, TMEM16/anoctamin......, and cystic fibrosis transmembrane conductance regulator (CFTR) in cellular apoptosis. LRRC8A-E has been identified as a volume-regulated anion channel expressed in many cell types. It was shown to be required for regulatory and apoptotic volume decrease (RVD, AVD) in cultured cell lines. Its presence also...

  15. Direct channel problems and phenomena

    International Nuclear Information System (INIS)

    Cutkosky, R.E.

    1975-01-01

    Direct channel problems and phenomena are considered covering the need for precision hadron spectroscopy, the data base for precision hadron spectroscopy, some relations between direct-channel and cross-channel effects, and spin rotation phenomena

  16. Rol de la colangio pancreatografía retrógrada endoscópica en pacientes con pancreatitis aguda biliar leve y vesícula in situ

    OpenAIRE

    ANSELMI M,MARIO; GEMMATO P,ANA MARÍA

    2011-01-01

    Objetivo: Analizar en forma prospectiva los resultados de la Colangio Pancreatografía Retrógrada Endoscópica (CPRE) y eventual manejo endoscópico en pacientes portadores de pancreatitis aguda biliar (PAB) leve con vesícula in situ. Material y Método: Se estudiaron 90 pacientes consecutivos con PAB leve y vesícula in situ. La edad promedio fue de 49,5 ± 18,6 años (78,9% mujeres y 21,1% hombres). Del total, 49 pacientes (54,4%) presentaron ictericia y 12 (13,3%) colangitis. Resultados: La CPRE ...

  17. Channel arrangements and depositional styles in the São Lourenço fluvial megafan, Brazilian Pantanal wetland

    Science.gov (United States)

    Assine, Mario Luis; Corradini, Fabrício Anibal; Pupim, Fabiano do Nascimento; McGlue, Michael Matthew

    2014-03-01

    The Brazilian Pantanal is an extensive lowland tropical basin characterized by the presence of fluvial megafans and seasonally-inundated savanna floodplain wetlands. With an area of about 16,000 km2, the São Lourenço is the second largest megafan in the Pantanal. Three distinct fluvial channel styles that formed at different times during the late Quaternary are found here. A geomorphological and sedimentary assessment of these depositional patterns provides valuable insight on the environmental context of their evolution. New optically stimulated luminescence data indicate that the upper five meters of sediment in the São Lourenço megafan has been accumulating since the late Pleistocene. Ancient fan lobes, located in upper and intermediate fan settings, consist of medium- and coarse-grained fluvial sands and exhibit well-preserved distributary braided paleochannels on their surfaces. As the megafan evolved through time, Pleistocene lobes were incised by a prominent valley filled with Holocene-aged meander belt deposits, which consist of silts interbedded with very fine sands and clays. Currently, the incised valley is a zone of sediment bypass. Modern deposition occurs along the distal toe of the megafan system, where lobes characterized by distributary channel-levee ridges are widespread. These features formed by progradation of avulsion belts into a broad swampy floodbasin, which caused the lower portion of the meander belt to be abandoned. The significant differences observed in intra-fan morphology appear to be linked to the variability in effective precipitation. Fan lobes deposited with braided distributary channels occurred under relatively dry conditions in the late Pleistocene. By contrast, aggradational meander belt deposits and lobes with distributary channel-levee ridges formed during fluctuating precipitation conditions of the Holocene, when the Pantanal emerged from deglacial aridity. Modern lobes form under heavy seasonal flooding and deposition

  18. Study on Dissipation of Landslide Generated Waves in Different Shape of Reservoirs

    Science.gov (United States)

    An, Y.; Liu, Q.

    2017-12-01

    The landslide generated waves are major risks for many reservoirs located in mountainous areas. As the initial wave is often very huge (e.g. 30m of the height in Xiaowan event, 2009, China), the dissipation of the wave, which is closely connected with the shape of the reservoir (e.g. channel type vs. lake type), is a crucial factor in risk estimation and prevention. While even for channel type reservoir, the wave damping also varies a lot due to details of the shape such as branches and turnings. Focusing on the influence of this shape details on the wave damping in channel type reservoir, we numerically studied two landslide generated wave events with both a triangle shape of the cross section but different longitudinal shape configurations (Xiaowan event in 2009 and an assuming event in real topography). The two-dimensional Saint-Venant equation and dry-wet boundary treatment method are used to simulate the wave generation and propagation processes. The simulation is based on an open source code called `Basilisk' and the adaptive mesh refinement technique is used to achieve enough precision with affordable computational resources. The sensitivity of the parameters representing bed drag and the vortex viscosity is discussed. We found that the damping is relatively not sensitive to the bed drag coefficient, which is natural as the water depth is large compared with wave height. While the vortex viscosity needs to be chosen carefully as it is related to cross sectional velocity distribution. It is also found that the longitudinal shape, i.e. the number of turning points and branches, is the key factor influencing the wave damping. The wave height at the far field could be only one seventh comparing with the initial wave in the case with complex longitudinal shape, while the damping is much weaker in the straight channel case. We guess that this phenomenon is due to the increasing sloshing at these abruptly changed positions. This work could provide a deeper

  19. INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2001-08-08

    novel alkaline-steam well completion technique for the containment of the unconsolidated formation sands and control of fluid entry and injection profiles. (5) Installation of a 2100 ft, 14 inch insulated, steam line beneath a harbor channel to supply steam to an island location. (6) Testing and proposed application of thermal recovery technologies to increase oil production and reserves: (a) Performing pilot tests of cyclic steam injection and production on new horizontal wells. (b) Performing pilot tests of hot water-alternating-steam (WAS) drive in the existing steam drive area to improve thermal efficiency. (7) Perform a pilot steamflood with the four horizontal injectors and producers using a pseudo steam-assisted gravity-drainage (SAGD) process. (8) Advanced reservoir management, through computer-aided access to production and geologic data to integrate reservoir characterization, engineering, monitoring and evaluation.

  20. Channel Choice: A Literature Review

    DEFF Research Database (Denmark)

    Østergaard Madsen, Christian; Kræmmergaard, Pernille

    2015-01-01

    The channel choice branch of e-government studies citizens’ and businesses’ choice of channels for interacting with government, and how government organizations can integrate channels and migrate users towards the most cost-efficient channels. In spite of the valuable contributions offered no sys...... no systematic overview exist of channel choice. We present a literature review of channel choice studies in government to citizen context identifying authors, countries, methods, concepts, units of analysis, and theories, and offer suggestionsfor future studies....

  1. Upper Hiwassee River Basin reservoirs 1989 water quality assessment

    International Nuclear Information System (INIS)

    Fehring, J.P.

    1991-08-01

    The water in the Upper Hiwassee River Basin is slightly acidic and low in conductivity. The four major reservoirs in the Upper Hiwassee River Basin (Apalachia, Hiwassee, Chatuge, and Nottely) are not threatened by acidity, although Nottely Reservoir has more sulfates than the other reservoirs. Nottely also has the highest organic and nutrient concentrations of the four reservoirs. This results in Nottely having the poorest water clarity and the most algal productivity, although clarity as measured by color and secchi depths does not indicate any problem with most water use. However, chlorophyll concentrations indicate taste and odor problems would be likely if the upstream end of Nottely Reservoir were used for domestic water supply. Hiwassee Reservoir is clearer and has less organic and nutrient loading than either of the two upstream reservoirs. All four reservoirs have sufficient algal activity to produce supersaturated dissolved oxygen conditions and relatively high pH values at the surface. All four reservoirs are thermally stratified during the summer, and all but Apalachia have bottom waters depleted in oxygen. The very short residence time of Apalachia Reservoir, less than ten days as compared to over 100 days for the other three reservoirs, results in it being more riverine than the other three reservoirs. Hiwassee Reservoir actually develops three distinct water temperature strata due to the location of the turbine intake. The water quality of all of the reservoirs supports designated uses, but water quality complaints are being received regarding both Chatuge and Nottely Reservoirs and their tailwaters

  2. Beyond the replication-competent HIV reservoir: transcription and translation-competent reservoirs.

    Science.gov (United States)

    Baxter, Amy E; O'Doherty, Una; Kaufmann, Daniel E

    2018-02-02

    Recent years have seen a substantial increase in the number of tools available to monitor and study HIV reservoirs. Here, we discuss recent technological advances that enable an understanding of reservoir dynamics beyond classical assays to measure the frequency of cells containing provirus able to propagate a spreading infection (replication-competent reservoir). Specifically, we focus on the characterization of cellular reservoirs containing proviruses able to transcribe viral mRNAs (so called transcription-competent) and translate viral proteins (translation-competent). We suggest that the study of these alternative reservoirs provides complementary information to classical approaches, crucially at a single-cell level. This enables an in-depth characterization of the cellular reservoir, both following reactivation from latency and, importantly, directly ex vivo at baseline. Furthermore, we propose that the study of cellular reservoirs that may not contain fully replication-competent virus, but are able to produce HIV mRNAs and proteins, is of biological importance. Lastly, we detail some of the key contributions that the study of these transcription and translation-competent reservoirs has made thus far to investigations into HIV persistence, and outline where these approaches may take the field next.

  3. Reservoir architecture and tough gas reservoir potential of fluvial crevasse-splay deposits

    NARCIS (Netherlands)

    Van Toorenenburg, K.A.; Donselaar, M.E.; Weltje, G.J.

    2015-01-01

    Unconventional tough gas reservoirs in low-net-to-gross fluvial stratigraphic intervals may constitute a secondary source of fossil energy to prolong the gas supply in the future. To date, however, production from these thin-bedded, fine-grained reservoirs has been hampered by the economic risks

  4. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Wiggins, Michael L.; Brown, Raymon L.; Civan, Frauk; Hughes, Richard G.

    2001-08-15

    Research continues on characterizing and modeling the behavior of naturally fractured reservoir systems. Work has progressed on developing techniques for estimating fracture properties from seismic and well log data, developing naturally fractured wellbore models, and developing a model to characterize the transfer of fluid from the matrix to the fracture system for use in the naturally fractured reservoir simulator.

  5. Application of integrated reservoir management and reservoir characterization to optimize infill drilling, Class II

    Energy Technology Data Exchange (ETDEWEB)

    Bergeron, Jack; Blasingame, Tom; Doublet, Louis; Kelkar, Mohan; Freeman, George; Callard, Jeff; Moore, David; Davies, David; Vessell, Richard; Pregger, Brian; Dixon, Bill; Bezant, Bryce

    2000-03-16

    The major purpose of this project was to demonstrate the use of cost effective reservoir characterization and management tools that will be helpful to both independent and major operators for the optimal development of heterogeneous, low permeability carbonate reservoirs such as the North Robertson (Clearfork) Unit.

  6. PLANET TOPERS: Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS.

    Science.gov (United States)

    Dehant, V; Asael, D; Baland, R M; Baludikay, B K; Beghin, J; Belza, J; Beuthe, M; Breuer, D; Chernonozhkin, S; Claeys, Ph; Cornet, Y; Cornet, L; Coyette, A; Debaille, V; Delvigne, C; Deproost, M H; De WInter, N; Duchemin, C; El Atrassi, F; François, C; De Keyser, J; Gillmann, C; Gloesener, E; Goderis, S; Hidaka, Y; Höning, D; Huber, M; Hublet, G; Javaux, E J; Karatekin, Ö; Kodolanyi, J; Revilla, L Lobo; Maes, L; Maggiolo, R; Mattielli, N; Maurice, M; McKibbin, S; Morschhauser, A; Neumann, W; Noack, L; Pham, L B S; Pittarello, L; Plesa, A C; Rivoldini, A; Robert, S; Rosenblatt, P; Spohn, T; Storme, J -Y; Tosi, N; Trinh, A; Valdes, M; Vandaele, A C; Vanhaecke, F; Van Hoolst, T; Van Roosbroek, N; Wilquet, V; Yseboodt, M

    2016-11-01

    The Interuniversity Attraction Pole (IAP) 'PLANET TOPERS' (Planets: Tracing the Transfer, Origin, Preservation, and Evolution of their Reservoirs) addresses the fundamental understanding of the thermal and compositional evolution of the different reservoirs of planetary bodies (core, mantle, crust, atmosphere, hydrosphere, cryosphere, and space) considering interactions and feedback mechanisms. Here we present the first results after 2 years of project work.

  7. Multi-data reservoir history matching for enhanced reservoir forecasting and uncertainty quantification

    KAUST Repository

    Katterbauer, Klemens

    2015-04-01

    Reservoir simulations and history matching are critical for fine-tuning reservoir production strategies, improving understanding of the subsurface formation, and forecasting remaining reserves. Production data have long been incorporated for adjusting reservoir parameters. However, the sparse spatial sampling of this data set has posed a significant challenge for efficiently reducing uncertainty of reservoir parameters. Seismic, electromagnetic, gravity and InSAR techniques have found widespread applications in enhancing exploration for oil and gas and monitoring reservoirs. These data have however been interpreted and analyzed mostly separately, rarely exploiting the synergy effects that could result from combining them. We present a multi-data ensemble Kalman filter-based history matching framework for the simultaneous incorporation of various reservoir data such as seismic, electromagnetics, gravimetry and InSAR for best possible characterization of the reservoir formation. We apply an ensemble-based sensitivity method to evaluate the impact of each observation on the estimated reservoir parameters. Numerical experiments for different test cases demonstrate considerable matching enhancements when integrating all data sets in the history matching process. Results from the sensitivity analysis further suggest that electromagnetic data exhibit the strongest impact on the matching enhancements due to their strong differentiation between water fronts and hydrocarbons in the test cases.

  8. Volume Regulated Channels

    DEFF Research Database (Denmark)

    Klausen, Thomas Kjær

    , controlled cell death and cellular migration. Volume regulatory mechanisms has long been in focus for regulating cellular proliferation and my thesis work have been focusing on the role of Cl- channels in proliferation with specific emphasis on ICl, swell. Pharmacological blockage of the ubiquitously...... but are also essential for a number of physiological processes such as proliferation, controlled cell death, migration and endocrinology. The thesis have been focusing on two Channels, namely the swelling activated Cl- channel (ICl, swell) and the transient receptor potential Vanilloid (TRPV4) channel. I: Cl...... understood. Potential agonist binding sites have been proposed in transmembrane domains 3 and 4, in congruence with agonist binding sites of TRPV1. However, the functional relationship between TRPV4 and agonist binding is not yet understood. In this thesis is further elaborate the structure...

  9. Sensing with Ion Channels

    CERN Document Server

    Martinac, Boris

    2008-01-01

    All living cells are able to detect and translate environmental stimuli into biologically meaningful signals. Sensations of touch, hearing, sight, taste, smell or pain are essential to the survival of all living organisms. The importance of sensory input for the existence of life thus justifies the effort made to understand its molecular origins. Sensing with Ion Channels focuses on ion channels as key molecules enabling biological systems to sense and process the physical and chemical stimuli that act upon cells in their living environment. Its aim is to serve as a reference to ion channel specialists and as a source of new information to non specialists who want to learn about the structural and functional diversity of ion channels and their role in sensory physiology.

  10. Calcium channel blocker poisoning

    Directory of Open Access Journals (Sweden)

    Miran Brvar

    2005-04-01

    Full Text Available Background: Calcium channel blockers act at L-type calcium channels in cardiac and vascular smooth muscles by preventing calcium influx into cells with resultant decrease in vascular tone and cardiac inotropy, chronotropy and dromotropy. Poisoning with calcium channel blockers results in reduced cardiac output, bradycardia, atrioventricular block, hypotension and shock. The findings of hypotension and bradycardia should suggest poisoning with calcium channel blockers.Conclusions: Treatment includes immediate gastric lavage and whole-bowel irrigation in case of ingestion of sustainedrelease products. All patients should receive an activated charcoal orally. Specific treatment includes calcium, glucagone and insulin, which proved especially useful in shocked patients. Supportive care including the use of catecholamines is not always effective. In the setting of failure of pharmacological therapy transvenous pacing, balloon pump and cardiopulmonary by-pass may be necessary.

  11. Coding for optical channels

    CERN Document Server

    Djordjevic, Ivan; Vasic, Bane

    2010-01-01

    This unique book provides a coherent and comprehensive introduction to the fundamentals of optical communications, signal processing and coding for optical channels. It is the first to integrate the fundamentals of coding theory and optical communication.

  12. Arsenic in freshwater fish in the Chihuahua County water reservoirs (Mexico).

    Science.gov (United States)

    Nevárez, Myrna; Moreno, Myriam Verónica; Sosa, Manuel; Bundschuh, Jochen

    2011-01-01

    Water reservoirs in Chihuahua County, Mexico, are affected by some punctual and non-punctual geogenic and anthropogenic pollution sources; fish are located at the top of the food chain and are good indicators for the ecosystems pollution. The study goal was to: (i) determine arsenic concentration in fish collected from the Chuviscar, Chihuahua, San Marcos and El Rejon water reservoirs; (ii) to assess if the fishes are suitable for human consumption and (iii) link the arsenic contents in fish with those in sediment and water reported in studies made the same year for these water reservoirs. Sampling was done in summer, fall and winter. The highest arsenic concentration in the species varied through the sampling periods: Channel catfish (Ictalurus punctatus) with 0.22 ± 0.15 mg/kg dw in winter and Green sunfish (Lepomis cyanellus) with 2.00 ± 0.15 mg/kg dw in summer in El Rejon water reservoir. A positive correlation of arsenic contents was found through all sampling seasons in fish samples and the samples of sediment and water. The contribution of the weekly intake of inorganic arsenic, based on the consumption of 0.245 kg fish muscles/body weight/week was found lower than the acceptable weekly intake of 0.015 mg/kg/body weight for inorganic arsenic suggested by FAO/WHO.

  13. Study on detailed geological modelling for fluvial sandstone reservoir in Daqing oil field

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Hanqing; Fu Zhiguo; Lu Xiaoguang [Institute of Petroleum Exploration and Development, Daqing (China)

    1997-08-01

    Guided by the sedimentation theory and knowledge of modern and ancient fluvial deposition and utilizing the abundant information of sedimentary series, microfacies type and petrophysical parameters from well logging curves of close spaced thousands of wells located in a large area. A new method for establishing detailed sedimentation and permeability distribution models for fluvial reservoirs have been developed successfully. This study aimed at the geometry and internal architecture of sandbodies, in accordance to their hierarchical levels of heterogeneity and building up sedimentation and permeability distribution models of fluvial reservoirs, describing the reservoir heterogeneity on the light of the river sedimentary rules. The results and methods obtained in outcrop and modem sedimentation studies have successfully supported the study. Taking advantage of this method, the major producing layers (PI{sub 1-2}), which have been considered as heterogeneous and thick fluvial reservoirs extending widely in lateral are researched in detail. These layers are subdivided into single sedimentary units vertically and the microfacies are identified horizontally. Furthermore, a complex system is recognized according to their hierarchical levels from large to small, meander belt, single channel sandbody, meander scroll, point bar, and lateral accretion bodies of point bar. The achieved results improved the description of areal distribution of point bar sandbodies, provide an accurate and detailed framework model for establishing high resolution predicting model. By using geostatistic technique, it also plays an important role in searching for enriched zone of residual oil distribution.

  14. Characterization of geomorphic units in the alluvial valleys and channels of Gulf Coastal Plain rivers in Texas, with examples from the Brazos, Sabine, and Trinity Rivers, 2010

    Science.gov (United States)

    Coffman, David K.; Malstaff, Greg; Heitmuller, Franklin T.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the Texas Water Development Board, described and characterized examples of geomorphic units within the channels and alluvial valleys of Texas Gulf Coastal Plain rivers using a geomorphic unit classification scale that differentiates geomorphic units on the basis of their location either outside or inside the river channel. The geomorphic properties of a river system determine the distribution and type of potential habitat both within and adjacent to the channel. This report characterizes the geomorphic units contained in the river channels and alluvial valleys of Texas Gulf Coastal Plain rivers in the context of the River Styles framework. This report is intended to help Texas Instream Flow Program practitioners, river managers, ecologists and biologists, and others interested in the geomorphology and the physical processes of the rivers of the Texas Gulf Coastal Plain (1) gain insights into how geomorphic units develop and adjust spatially and temporally, and (2) be able to recognize common geomorphic units from the examples cataloged in this report. Recent aerial imagery (high-resolution digital orthoimagery) collected in 2008 and 2009 were inspected by using geographic information system software to identify representative examples of the types of geomorphic units that occurred in the study area. Geomorphic units outside the channels of Texas Gulf Coastal Plain rivers are called \\"valley geomorphic units\\" in this report. Valley geomorphic units for the Texas Gulf Coastal Plain rivers described in this report are terraces, flood plains, crevasses and crevasse splays, flood-plain depressions, tie channels, tributaries, paleochannels, anabranches, distributaries, natural levees, neck cutoffs, oxbow lakes, and constructed channels. Channel geomorphic units occur in the river channel and are subject to frequent stresses associated with flowing water and sediment transport; they adjust (change) relatively quickly in

  15. Tritium in the Channel

    International Nuclear Information System (INIS)

    Masson, M.; Fievet, B.; Bailly-Du-Bois, P.; Olivier, A.; Tenailleau, L.

    2009-01-01

    After having recalled that sea waters entering the Channel exhibit a natural concentration of tritium, the authors outline that spent nuclear fuel reprocessing plants are now the main sources of tritium for marine ecosystems as some oceanographic campaigns showed it. If data about the presence of tritium in water are numerous, data concerning the presence of tritiated water and of organically bound tritium in organisms are much less frequent. However, some surveys have been performed along the Channel French coasts

  16. Channelling versus inversion

    DEFF Research Database (Denmark)

    Gale, A.S.; Surlyk, Finn; Anderskouv, Kresten

    2013-01-01

    Evidence from regional stratigraphical patterns in Santonian−Campanian chalk is used to infer the presence of a very broad channel system (5 km across) with a depth of at least 50 m, running NNW−SSE across the eastern Isle of Wight; only the western part of the channel wall and fill is exposed. W......−Campanian chalks in the eastern Isle of Wight, involving penecontemporaneous tectonic inversion of the underlying basement structure, are rejected....

  17. Reservoir Characterization, Production Characteristics, and Research Needs for Fluvial/Alluvial Reservoirs in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Cole, E.L.; Fowler, M.L.; Jackson, S.R.; Madden, M.P.; Raw-Schatzinger, V.; Salamy, S.P.; Sarathi, P.; Young, M.A.

    1999-04-28

    The Department of Energy's (DOE's) Oil Recovery Field Demonstration Program was initiated in 1992 to maximize the economically and environmentally sound recovery of oil from known domestic reservoirs and to preserve access to this resource. Cost-shared field demonstration projects are being initiated in geology defined reservoir classes which have been prioritized by their potential for incremental recovery and their risk of abandonment. This document defines the characteristics of the fifth geological reservoir class in the series, fluvial/alluvial reservoirs. The reservoirs of Class 5 include deposits of alluvial fans, braided streams, and meandering streams. Deposit morphologies vary as a complex function of climate and tectonics and are characterized by a high degree of heterogeneity to fluid flow as a result of extreme variations in water energy as the deposits formed.

  18. Course on Ionic Channels

    CERN Document Server

    1986-01-01

    This book is based on a series of lectures for a course on ionic channels held in Santiago, Chile, on November 17-20, 1984. It is intended as a tutorial guide on the properties, function, modulation, and reconstitution of ionic channels, and it should be accessible to graduate students taking their first steps in this field. In the presentation there has been a deliberate emphasis on the spe­ cific methodologies used toward the understanding of the workings and function of channels. Thus, in the first section, we learn to "read" single­ channel records: how to interpret them in the theoretical frame of kinetic models, which information can be extracted from gating currents in re­ lation to the closing and opening processes, and how ion transport through an open channel can be explained in terms of fluctuating energy barriers. The importance of assessing unequivocally the origin and purity of mem­ brane preparations and the use of membrane vesicles and optical tech­ niques in the stUGY of ionic channels a...

  19. Environmental Factors Affecting Mercury in Camp Far West Reservoir, California, 2001-03

    Science.gov (United States)

    Alpers, Charles N.; Stewart, A. Robin; Saiki, Michael K.; Marvin-DiPasquale, Mark C.; Topping, Brent R.; Rider, Kelly M.; Gallanthine, Steven K.; Kester, Cynthia A.; Rye, Robert O.; Antweiler, Ronald C.; De Wild, John F.

    2008-01-01

    This report documents water quality in Camp Far West Reservoir from October 2001 through August 2003. The reservoir, located at approximately 300 feet above sea level in the foothills of the northwestern Sierra Nevada, California, is a monomictic lake characterized by extreme drawdown in the late summer and fall. Thermal stratification in summer and fall is coupled with anoxic conditions in the hypolimnion. Water-quality sampling was done at approximately 3-month intervals on eight occasions at several stations in the reservoir, including a group of three stations along a flow path in the reservoir: an upstream station in the Bear River arm (principal tributary), a mid-reservoir station in the thalweg (prereservoir river channel), and a station in the deepest part of the reservoir, in the thalweg near Camp Far West Dam. Stations in other tributary arms of the reservoir included those in the Rock Creek arm of the reservoir, a relatively low-flow tributary, and the Dairy Farm arm, a small tributary that receives acidic, metal-rich drainage seasonally from the inactive Dairy Farm Mine, which produced copper, zinc, and gold from underground workings and a surface pit. Several water-quality constituents varied significantly by season at all sampling stations, including major cations and anions, total mercury (filtered and unfiltered samples), nitrogen (ammonia plus organic), and total phosphorus. A strong seasonal signal also was observed for the sulfurisotope composition of aqueous sulfate from filtered water. Although there were some spatial differences in water quality, the seasonal variations were more profound. Concentrations of total mercury (filtered and unfiltered water) were highest during fall and winter; these concentrations decreased at most stations during spring and summer. Anoxic conditions developed in deep parts of the reservoir during summer and fall in association with thermal stratification. The highest concentrations of methylmercury in unfiltered

  20. Bibliography of U.S. Geological Survey studies of lakes and reservoirs; the first 100 years

    Science.gov (United States)

    Winter, Thomas C.

    1982-01-01

    paleobiological studies of ancient lakes. This report does, however, include geological studies of proposed reservoir sites. This bibliography has three parts. The first part is an alphabetical listing that gives complete references to the given reports. Part 2 is a listing by topics, and only the authors, date of publication, and cross-reference to the State are given. Six general categories are considered: Lake hydrology; interaction of lakes and streamflow, including geological studies of reservoir sites; interaction of lakes and atmospheric water; interaction of lakes. and ground water; chemical and biological limnology; and sediment studies. The first four consist of studies of physical characteristics of lakes, and the last two of water-quality characteristics. The category of lake hydrology includes general studies of lakes that are not easily grouped into one of the more specific categories of physical characteristics. For example, it includes water-budget studies where all aspects of hydrology are discussed. It also includes studies of hydrodynamics of lakes as well as studies of lake-level fluctuations. The category of interaction of lakes and streamflow includes preimpoundment studies of streamflow discharge for reservoir design, and studies of the effects of existing reservoirs on streamflow and channel characteristics. Also included in this category are geological studies of river valleys for proposed reservoir sites. The category of interaction of lakes and atmospheric water includes primarily studies of evaporation. The interaction of lakes and ground water includes studies of bank storage. The category of chemical and biological studies was not subdivided into more specific types because of the virtually inseparable relation between chemistry and biology in most studies. This bibliography provided much of the information for two papers that discuss the history of U.S. Geological Survey studies of lakes and reservoirs. (See Winter, 1981b; and Hadley, 1981).

  1. Saturation distributions in heavy oil reservoirs

    Science.gov (United States)

    Staten, Joshua Todd

    Models that describe conventional reservoirs can be used to explore the possibility of heavier-than-water oil. Steam-assisted gravity drainage (SAGD) is a common process in reservoirs with extra heavy oils (oil sands). In some cases, oil that is heavier than water is present in these reservoirs. The segregation of oil and water may cause issues for recovery. It is important to understand the initial saturation distribution of oil and water for proper design of injection. It was found through simulation that the heavy oil would pool towards the bottom of a heavy oil reservoir with water remaining on top of the oil. With capillary pressure, the heavy oil and water will form a transition zone. The extent of the transition zone is dependent on the density gradient of the oil, the density difference between the oil and water, and the slope of the capillary pressure saturation profile. This finding influences the positioning of production piping in steam-assisted gravity drainage (SAGD) as well as possible geological pooling areas for recovery. The possibility of a water zone between oil zones increases the risk of missing oil in the reservoir when drilling or perforating.

  2. Model based management of a reservoir system

    Energy Technology Data Exchange (ETDEWEB)

    Scharaw, B.; Westerhoff, T. [Fraunhofer IITB, Ilmenau (Germany). Anwendungszentrum Systemtechnik; Puta, H.; Wernstedt, J. [Technische Univ. Ilmenau (Germany)

    2000-07-01

    The main goals of reservoir management systems consist of prevention against flood water damages, the catchment of raw water and keeping all of the quality parameters within their limits besides controlling the water flows. In consideration of these goals a system model of the complete reservoir system Ohra-Schmalwasser-Tambach Dietharz was developed. This model has been used to develop optimized strategies for minimization of raw water production cost, for maximization of electrical energy production and to cover flood situations, as well. Therefore a proper forecast of the inflow to the reservoir from the catchment areas (especially flooding rivers) and the biological processes in the reservoir is important. The forecast model for the inflow to the reservoir is based on the catchment area model of Lorent and Gevers. It uses area precipitation, water supply from the snow cover, evapotranspiration and soil wetness data to calculate the amount of flow in rivers. The other aim of the project is to ensure the raw water quality using quality models, as well. Then a quality driven raw water supply will be possible. (orig.)

  3. Mechanisms of HIV persistence in HIV reservoirs.

    Science.gov (United States)

    Mzingwane, Mayibongwe L; Tiemessen, Caroline T

    2017-03-01

    The establishment and maintenance of HIV reservoirs that lead to persistent viremia in patients on antiretroviral drugs remains the greatest challenge of the highly active antiretroviral therapy era. Cellular reservoirs include resting memory CD4+ T lymphocytes, implicated as the major HIV reservoir, having a half-life of approximately 44 months while this is less than 6 hours for HIV in plasma. In some individuals, persistent viremia consists of invariant HIV clones not detected in circulating resting CD4+ T lymphocytes suggesting other possible sources of residual viremia. Some anatomical reservoirs that may harbor such cells include the brain and the central nervous system, the gastrointestinal tract and the gut-associated lymphoid tissue and other lymphoid organs, and the genital tract. The presence of immune cells and other HIV susceptible cells, occurring in differing compositions in anatomical reservoirs, coupled with variable and poor drug penetration that results in suboptimal drug concentrations in some sites, are all likely factors that fuel the continued low-level replication and persistent viremia during treatment. Latently, HIV-infected CD4+ T cells harboring replication-competent virus, HIV cell-to-cell spread, and HIV-infected T cell homeostatic proliferation due to chronic immune activation represent further drivers of this persistent HIV viremia during highly active antiretroviral therapy. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Mercury and methylmercury in reservoirs in Indiana

    Science.gov (United States)

    Risch, Martin R.; Fredericksen, Amanda L.

    2015-01-01

    Mercury (Hg) is an element that occurs naturally, but evidence suggests that human activities have resulted in increased amounts being released to the atmosphere and land surface. When Hg is converted to methylmercury (MeHg) in aquatic ecosystems, MeHg accumulates and increases in the food web so that some fish contain levels which pose a health risk to humans and wildlife that consume these fish. Reservoirs unlike natural lakes, are a part of river systems that are managed for flood control. Data compiled and interpreted for six flood-control reservoirs in Indiana showed a relation between Hg transport, MeHg formation in water, and MeHg in fish that was influenced by physical, chemical, and biological differences among the reservoirs. Existing information precludes a uniform comparison of Hg and MeHg in all reservoirs in the State, but factors and conditions were identified that can indicate where and when Hg and MeHg levels in reservoirs could be highest.

  5. Physical modelling of the Akkajaure reservoir

    Directory of Open Access Journals (Sweden)

    J. Sahlberg

    2003-01-01

    Full Text Available This paper describes the seasonal temperature development in the Akkajaure reservoir, one of the largest Swedish reservoirs. It lies in the headwaters of the river Lulealven in northern Sweden; it is 60 km long and 5 km wide with a maximum depth of 92 m. The maximum allowed variation in surface water level is 30 m. The temperature field in the reservoir is important for many biochemical processes. A one-dimensional lake model of the Akkajaure reservoir is developed from a lake model by Sahlberg (1983 and 1988. The dynamic eddy viscosity is calculated by a two equation turbulence model, a k–ε model and the hypolimnic eddy diffusivity formulation which is a function of the stability frequency (Hondzo et al., 1993. A comparison between calculated and measured temperature profiles showed a maximum discrepancy of 0.5–1.0°C over the period 1999-2002. Except for a few days in summer, the water temperature is vertically homogeneous. Over that period of years, a weak stratification of temperature occurred on only one to two weeks a year on different dates in July and August. This will have biological consequences. Keywords: temperature profile,reservoir, 1-D lake model, stratification, Sweden

  6. Integral cesium reservoir: Design and transient operation

    Science.gov (United States)

    Smith, Joe N., Jr.; Horner, M. Harlan; Begg, Lester L.; Wrobleski, William J.

    An electrically heated thermionic converter has been designed built and successfully tested in air. One of the unique features of this converter was an integral cesium reservoir thermally coupled to the emitter. The reservoir consisted of fifteen cesiated graphite pins located in pockets situated in the emitter lead with thermal coupling to the emitter, collector and the emitter terminal; there were no auxiliary electric heaters on the reservoir. Test results are described for conditions in which the input thermal power to the converter was ramped up and down between 50% and 100% of full power in times as short as 50 sec, with data acquisition occurring every 12 sec. During the ramps the emitter and collector temperature profiles. the reservoir temperature and the electric output into a fixed load resistor are reported. The converter responded promptly to the power ramps without excessive overshoot and with no tendency to develop instabilities. This is the rust demonstration of the performance of a cesium-graphite integral reservoir in a fast transient.

  7. Tracing fluid flow in geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Rose, P.E.; Adams, M.C. [Univ. of Utah, Salt Lake City, UT (United States)

    1997-12-31

    A family of fluorescent compounds, the polycyclic aromatic sulfonates, were evaluated for application in intermediate- and high-temperature geothermal reservoirs. Whereas the naphthalene sulfonates were found to be very thermally stable and reasonably detectable, the amino-substituted naphthalene sulfonates were found to be somewhat less thermally stable, but much more detectable. A tracer test was conducted at the Dixie Valley, Nevada, geothermal reservoir using one of the substituted naphthalene sulfonates, amino G, and fluorescein. Four of 9 production wells showed tracer breakthrough during the first 200 days of the test. Reconstructed tracer return curves are presented that correct for the thermal decay of tracer assuming an average reservoir temperature of 227{degrees}C. In order to examine the feasibility of using numerical simulation to model tracer flow, we developed simple, two-dimensional models of the geothermal reservoir using the numerical simulation programs TETRAD and TOUGH2. By fitting model outputs to measured return curves, we show that numerical reservoir simulations can be calibrated with the tracer data. Both models predict the same order of elution, approximate tracer concentrations, and return curve shapes. Using these results, we propose a method for using numerical models to design a tracer test.

  8. Application of integrated reservoir management and reservoir characterization to optimize infill drilling. Quarterly progress report, June 13, 1995--September 12, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Pande, P.K.

    1995-09-12

    At this stage of the reservoir characterization research, the main emphasis is on the geostatistics and reservoir simulation. Progress is reported on geological analysis, reservoir simulation, and reservoir management.

  9. Entre armas leves e a regulamentação internacional: para que lado o Brasil dirige uma política pública?

    Directory of Open Access Journals (Sweden)

    Cristiano Armando Diniz Guerra Silvestre

    2016-08-01

    Full Text Available Resumo: O crescimento da atenção internacional acerca da temática relacionada a armas leves tem gerado várias ações que evidenciam esta preocupação no âmbito internacional. Diversas organizações multilaterais – como a ONU com seu Programa de Ação da ONU para Prevenir, Combater e Suprimir o Comércio Ilícito de Armas Pequenas e Armamentos Leves em Todos seus Aspectos – e não-governamentais – tendo a Caritas por exemplo, seguem registrando seu uso em diversas zonas de conflito do mundo. Entretanto, sua regulamentação no Direito Internacional Humanitário é esparsa, o que convém, sobretudo, aos fabricantes de armas. A Indústria de Defesa, como se apresenta na literatura do tema, tem sido incentivada indiscriminadamente no Brasil. Segundo o Small Arms Trade Survey, o país figura na quarta posição mundial em vendas de armas leves atrás somente de Estados Unidos, Itália e Alemanha. Por sua vez, o Ministério do Desenvolvimento, Indústria e Comércio Exterior (MDIC afirma que houve crescimento de 500% no valor de exportações deste setor, que passaram de US$ 109,6 milhões em 2005 para US$ 321,6 milhões em 2010, considerando somente as armas de fogo. Contudo, este não é um dado surpreendente, pois o incentivo a esta indústria aparece na Estratégia Nacional de Defesa de 2008. Esta pesquisa, realizada sob abordagem qualitativa e de acordo com o método indutivo com caráter prospectivo, segundo a técnica de pesquisa de análise de conteúdo jurídico-documental, apresenta a seguinte hipótese: que o desenvolvimento à indústria de Defesa tem sido fator a impedir a adoção medidas jurídicas mais enérgicas para o tratamento da regulamentação de armas convencionais, ainda que o Brasil seja signatário de alguns tratados sobre o tema.

  10. adequacy of drainage channels f drainage channels in a small

    African Journals Online (AJOL)

    eobe

    carried out and data obtain from drainage channels. The time of concentratio version of version of Kirpich equation (new equation of time new equation of time from the drainage channels were determined using results showed that most of the drainage channels h. All the drainage channels of basin A had velocities ra.

  11. Ion channelling in diamond

    International Nuclear Information System (INIS)

    Derry, T.E.

    1978-06-01

    Diamond is one of the most extreme cases from a channelling point of view, having the smallest thermal vibration amplitude and the lowest atomic number of commonly-encountered crystals. These are the two parameters most important for determining channelling behaviour. It is of consiberable interest therefore to see how well the theories explaining and predicting the channeling properties of other substance, succeed with diamond. Natural diamond, although the best available form for these experiments, is rather variable in its physical properties. Part of the project was devoted to considering and solving the problem of obtaining reproducible results representative of the ideal crystal. Channelling studies were performed on several good crystals, using the Rutherford backscattering method. Critical angles for proton channelling were measured for incident energies from 0.6 to 4.5 MeV, in the three most open axes and three most open planes of the diamond structure, and for α-particle channelling at 0.7 and 1.0 MeV (He + ) in the same axes and planes. For 1.0 MeV protons, the crystal temperature was varied from 20 degrees Celsius to 700 degrees Celsius. The results are presented as curves of backscattered yield versus angle in the region of each axis or plane, and summarised in the form of tables and graphs. Generally the critical angles, axial minimum yields, and temperature dependence are well predicted by the accepted theories. The most valuable overall conclusion is that the mean thermal vibration amplitude of the atoms in a crytical determines the critical approach distance to the channel walls at which an ion can remain channelled, even when this distance is much smaller than the Thomas-Fermi screening distance of the atomic potential, as is the case in diamond. A brief study was made of the radiation damage caused by α-particle bombardment, via its effect on the channelling phenomenon. It was possible to hold damage down to negligible levels during the

  12. Oil Reservoir Production Optimization using Optimal Control

    DEFF Research Database (Denmark)

    Völcker, Carsten; Jørgensen, John Bagterp; Stenby, Erling Halfdan

    2011-01-01

    Practical oil reservoir management involves solution of large-scale constrained optimal control problems. In this paper we present a numerical method for solution of large-scale constrained optimal control problems. The method is a single-shooting method that computes the gradients using the adjo...... reservoir using water ooding and smart well technology. Compared to the uncontrolled case, the optimal operation increases the Net Present Value of the oil field by 10%.......Practical oil reservoir management involves solution of large-scale constrained optimal control problems. In this paper we present a numerical method for solution of large-scale constrained optimal control problems. The method is a single-shooting method that computes the gradients using...

  13. Reservoir characterization and enhanced oil recovery research

    Energy Technology Data Exchange (ETDEWEB)

    Lake, L.W.; Pope, G.A.; Schechter, R.S.

    1992-03-01

    The research in this annual report falls into three tasks each dealing with a different aspect of enhanced oil recovery. The first task strives to develop procedures for accurately modeling reservoirs for use as input to numerical simulation flow models. This action describes how we have used a detail characterization of an outcrop to provide insights into what features are important to fluid flow modeling. The second task deals with scaling-up and modeling chemical and solvent EOR processes. In a sense this task is the natural extension of task 1 and, in fact, one of the subtasks uses many of the same statistical procedures for insight into the effects of viscous fingering and heterogeneity. The final task involves surfactants and their interactions with carbon dioxide and reservoir minerals. This research deals primarily with phenomena observed when aqueous surfactant solutions are injected into oil reservoirs.

  14. Greenhouse gas emissions from hydroelectric reservoirs

    International Nuclear Information System (INIS)

    Rosa, L.P.; Schaeffer, R.

    1994-01-01

    In a recent paper, Rudd et al. have suggested that, per unit of electrical energy produced, greenhouse-gas emissions from some hydroelectric reservoirs in northern Canada may be comparable to emissions from fossil-fuelled power plants. The purpose of this comment is to elaborate these issues further so as to understand the potential contribution of hydroelectric reservoirs to the greenhouse effect. More than focusing on the total budget of carbon emissions (be they in the form of CH 4 or be they in the form of CO 2 ), this requires an evaluation of the accumulated greenhouse effect of gas emissions from hydroelectric reservoirs and fossil-fuelled power plants. Two issues will be considered: (a) global warming potential (GWP) for CH 4 ; and (b) how greenhouse-gas emissions from hydroelectric power plants stand against emissions from fossil-fuelled power plants with respect to global warming

  15. Mechanical Testing Development for Reservoir Forgings

    Energy Technology Data Exchange (ETDEWEB)

    Wenski, E.G.

    2000-05-22

    The goal of this project was to determine the machining techniques and testing capabilities required for mechanical property evaluation of commercially procured reservoir forgings. Due to the small size of these specific forgings, specialized methods are required to adequately machine and test these sub-miniature samples in accordance with the requirements of ASTM-E8 and ASTM-E9. At the time of project initiation, no capability existed at Federal Manufacturing & Technologies (FM&T) to verify the physical properties of these reservoirs as required on the drawing specifications. The project determined the sample definitions, machining processes, and testing procedures to verify the physical properties of the reservoir forgings; specifically, tensile strength, yield strength, reduction of area, and elongation. In addition, a compression test method was also developed to minimize sample preparation time and provide a more easily machined test sample while maintaining the physical validation of the forging.

  16. Historical reservoir construction: potential hotspot of anthropogenic induced sediments in lowland Northeastern Romania

    Science.gov (United States)

    Niculita, Mihai; Ciprian Margarint, Mihai; Tarolli, Paolo

    2017-04-01

    The Northeastern Romania lowland is well known for its reservoir construction history and sedimentation all over the last 500 years. These reservoirs were in general small (under 1 million m3), shallow (4 - 5 m in depth, but with water levels of up to 3 m) and frequently dry during the summer or winter. Their construction was requested by the dryness of the climate, the reservoirs being used for water storage, pisciculture, for cereals mills and fuller mills. After their filling, the dam morphology was kept and became smooth over time. The dams were also cut in the spillway area in order to evacuate the groundwater, so the reservoir bottom could be used as pasture. This anthropic intervention created a concentration of flow at high water discharges in the spillway area, which allowed the evolution of gullies on the flat lacustrine bottom. We identified about 20 sites where this process of gullies affecting reservoir bottoms occurred in the last 75 years. For each site we estimated the volumes and mass of the eroded sediments using LIDAR DEMs, and established a temporal scale of gully activity using aerial imagery for estimating the rate of process. The total volume of eroded area is over 100000 m3, individual gullies volumes ranging from 2000 to 10000 m3. The maximum depth of the gullies is around 4 m, which is in general the maximum depth of reservoir sediments; the length of the gully systems is between 30 to 1500 m. The shape of the gully channels is branched, which we believe is because the formation and evolution of these landforms is related to the water flow at high discharge. We describe also similar patterns of gullies developed on flat floodplains of the study area and which are in general older than 75 years. The importance of the study of these erosional patterns is related to the potential of the reservoir bottoms to become erosional hot spots. In the study area there is an increase of extreme rainfall events, which coupled with the presence of over

  17. Tecnologias leves em saúde e sua relação com o cuidado de enfermagem hospitalar Tecnologías leves en salud y su relación con el cuidado de enfermería hospitalaria Light technologies in health and its relation with the hospital nursing care

    Directory of Open Access Journals (Sweden)

    Denise Conceição da Silva

    2008-06-01

    Full Text Available O objeto da pesquisa foi a incorporação de tecnologias leves no contexto hospitalar, na ótica de enfermeiras, e sua relação com o cuidado de enfermagem. Objetivos: caracterizar as tecnologias consideradas leves no hospital, na ótica de enfermeiras, e analisar as concepções de enfermeiras sobre o uso dessas tecnologias no cuidado de enfermagem. Fundamentou-se na classificação dos diferentes tipos de tecnologias no trabalho em saúde e em pressupostos sobre o cuidado de enfermagem. Pesquisa exploratória, qualitativo-descritiva, desenvolvida em dois hospitais universitários na Cidade do Rio de Janeiro. Os dados foram coletados através da técnica de criatividade e sensibilidade "Almanaque", conjugada à entrevista semi-estruturada. Do discurso das enfermeiras emergiram tecnologias fundamentadas em suas experiências de cuidado. Suas concepções sobre tecnologias leves revelaram o que teoristas de enfermagem referem como atributos da relação humana no cuidado. Essas, quando discutidas no âmbito do cuidado de enfermagem, emergem como qualidades do cuidado em si.El objeto de la investigación fue la incorporación de tecnologías leves en hospitales, desde la perspectiva de las enfermeras y las relaciones establecidas con el cuidado de enfermería. Objetivos: caracterizar las tecnologías consideradas leves en el hospital, desde la perspectiva de las enfermeras; y analizar las concepciones de las enfermeras sobre el uso de estas tecnologías en el cuidado de enfermería. El estudio se fundamentó en la clasificación de diferentes tipos de tecnologías aplicadas en el área de la salud y en presuposiciones sobre el cuidado de enfermería. Investigación exploratoria, cualitativa y descriptiva, desarrollada en dos hospitales universitarios de la ciudad de Rio de Janeiro. Los datos fueron recolectados a través de dos técnicas: creatividad y sensibilidad, denominada "Almanaque," y entrevista semi-estructurada. De los discursos de las

  18. Parallel processing using an optical delay-based reservoir computer

    Science.gov (United States)

    Van der Sande, Guy; Nguimdo, Romain Modeste; Verschaffelt, Guy

    2016-04-01

    Delay systems subject to delayed optical feedback have recently shown great potential in solving computationally hard tasks. By implementing a neuro-inspired computational scheme relying on the transient response to optical data injection, high processing speeds have been demonstrated. However, reservoir computing systems based on delay dynamics discussed in the literature are designed by coupling many different stand-alone components which lead to bulky, lack of long-term stability, non-monolithic systems. Here we numerically investigate the possibility of implementing reservoir computing schemes based on semiconductor ring lasers. Semiconductor ring lasers are semiconductor lasers where the laser cavity consists of a ring-shaped waveguide. SRLs are highly integrable and scalable, making them ideal candidates for key components in photonic integrated circuits. SRLs can generate light in two counterpropagating directions between which bistability has been demonstrated. We demonstrate that two independent machine learning tasks , even with different nature of inputs with different input data signals can be simultaneously computed using a single photonic nonlinear node relying on the parallelism offered by photonics. We illustrate the performance on simultaneous chaotic time series prediction and a classification of the Nonlinear Channel Equalization. We take advantage of different directional modes to process individual tasks. Each directional mode processes one individual task to mitigate possible crosstalk between the tasks. Our results indicate that prediction/classification with errors comparable to the state-of-the-art performance can be obtained even with noise despite the two tasks being computed simultaneously. We also find that a good performance is obtained for both tasks for a broad range of the parameters. The results are discussed in detail in [Nguimdo et al., IEEE Trans. Neural Netw. Learn. Syst. 26, pp. 3301-3307, 2015

  19. Characterization of oil and gas reservoir heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Tyler, N.; Barton, M.D.; Bebout, D.G.; Fisher, R.S.; Grigsby, J.D.; Guevara, E.; Holtz, M.; Kerans, C.; Nance, H.S.; Levey, R.A.

    1992-10-01

    Research described In this report addresses the internal architecture of two specific reservoir types: restricted-platform carbonates and fluvial-deltaic sandstones. Together, these two reservoir types contain more than two-thirds of the unrecovered mobile oil remaining ill Texas. The approach followed in this study was to develop a strong understanding of the styles of heterogeneity of these reservoir types based on a detailed outcrop description and a translation of these findings into optimized recovery strategies in select subsurface analogs. Research targeted Grayburg Formation restricted-platform carbonate outcrops along the Algerita Escarpment and In Stone Canyon In southeastern New Mexico and Ferron deltaic sandstones in central Utah as analogs for the North Foster (Grayburg) and Lake Creek (Wilcox) units, respectively. In both settings, sequence-stratigraphic style profoundly influenced between-well architectural fabric and permeability structure. It is concluded that reservoirs of different depositional origins can therefore be categorized Into a heterogeneity matrix'' based on varying intensity of vertical and lateral heterogeneity. The utility of the matrix is that it allows prediction of the nature and location of remaining mobile oil. Highly stratified reservoirs such as the Grayburg, for example, will contain a large proportion of vertically bypassed oil; thus, an appropriate recovery strategy will be waterflood optimization and profile modification. Laterally heterogeneous reservoirs such as deltaic distributary systems would benefit from targeted infill drilling (possibly with horizontal wells) and improved areal sweep efficiency. Potential for advanced recovery of remaining mobile oil through heterogeneity-based advanced secondary recovery strategies In Texas is projected to be an Incremental 16 Bbbl. In the Lower 48 States this target may be as much as 45 Bbbl at low to moderate oil prices over the near- to mid-term.

  20. Freshwater reservoir effect variability in Northern Germany

    DEFF Research Database (Denmark)

    Philippsen, B.; Heinemeier, J.

    2013-01-01

    The freshwater reservoir effect is a potential problem when radiocarbon dating fish bones, shells, human bones, or food crusts on pottery from sites near rivers or lakes. The reservoir age in hardwater rivers can be up to several thousand years and may be highly variable. Accurate 14C dating of f...... that can also be expected for the past. This knowledge will be applied to the dating of food crusts on pottery from the Mesolithic sites Kayhude at the Alster River and Schlamersdorf at the Trave River, both in Schleswig-Holstein, northern Germany....

  1. Pressure Transient Analysis of Dual Fractal Reservoir

    Directory of Open Access Journals (Sweden)

    Xiao-Hua Tan

    2013-01-01

    Full Text Available A dual fractal reservoir transient flow model was created by embedding a fracture system simulated by a tree-shaped fractal network into a matrix system simulated by fractal porous media. The dimensionless bottom hole pressure model was created using the Laplace transform and Stehfest numerical inversion methods. According to the model's solution, the bilogarithmic type curves of the dual fractal reservoirs are illustrated, and the influence of different fractal factors on pressure transient responses is discussed. This semianalytical model provides a practical and reliable method for empirical applications.

  2. Controls on Cementation in a Chalk Reservoir

    DEFF Research Database (Denmark)

    Meireles, Leonardo Teixeira Pinto; Hussein, A.; Welch, M.J.

    In this study, we identify different controls on cementation in a chalk reservoir. Biot’s coefficient, a measure of cementation, stiffness and strength in porous rocks, is calculated from logging data (bulk density and sonic Pwave velocity). We show that Biot’s coefficient is correlated...... to the water saturation of the Kraka reservoir and is partly controlled by its stratigraphic sub-units. While the direct causal relationship between Biot’s coefficient and water saturation cannot be extended for Biot’s coefficient and porosity, a correlation is also identified between the two, implying...

  3. Nonlinearities in reservoir engineering: Enhancing quantum correlations

    Science.gov (United States)

    Hu, Xiangming; Hu, Qingping; Li, Lingchao; Huang, Chen; Rao, Shi

    2017-12-01

    There are two decisive factors for quantum correlations in reservoir engineering, but they are strongly reversely dependent on the atom-field nonlinearities. One is the squeezing parameter for the Bogoliubov modes-mediated collective interactions, while the other is the dissipative rates for the engineered collective dissipations. Exemplifying two-level atomic ensembles, we show that the moderate nonlinearities can compromise these two factors and thus enhance remarkably two-mode squeezing and entanglement of different spin atomic ensembles or different optical fields. This suggests that the moderate nonlinearities of the two-level systems are more advantageous for applications in quantum networks associated with reservoir engineering.

  4. Characterization of oil and gas reservoir heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The objective of the cooperative research program is to characterize Alaskan reservoirs in terms of their reserves, physical and chemical properties, geologic configuration and structure, and the development potential. The tasks completed during this period include: (1) geologic reservoir description of Endicott Field; (2) petrographic characterization of core samples taken from selected stratigraphic horizons of the West Sak and Ugnu (Brookian) wells; (3) development of a polydispersed thermodynamic model for predicting asphaltene equilibria and asphaltene precipitation from crude oil-solvent mixtures, and (4) preliminary geologic description of the Milne Point Unit.

  5. Chalk reservoirs of the North Sea

    International Nuclear Information System (INIS)

    Hardman, R.F.P.

    1982-01-01

    The amount of clay in the chalk, whether primary or secondary, is the factor of greatest importance in determining whether chalk has the capability of forming a reservoir rock or not. It has been empirically observed that the less the clay content the better the resevoir and as has been remarked earlier, the amount of clay in the Chalk can be closely correlated with sea level. changes. Where other factors are either absent or of only minor importance, the effect of clay is most clearly seen. A good example is well N-2 in Danish waters. It is concluded that in N-2 clay is the dominant control on reservoir quality. (EG)

  6. El trabajo preventivo en alumnos con retraso mental leve que no cumplen con sus deberes escolares, mediante el uso del psicodrama

    Directory of Open Access Journals (Sweden)

    Griselda Matos Sarmiento

    2017-11-01

    Full Text Available El presente artículo consta de acciones encaminadas a la preparación de los docentes para mejorar el trabajo preventivo en alumnos con retraso mental leve que no cumplen con sus deberes escolares y que además constituyen un grupo muy heterogéneo. Para realizar este trabajo, se tuvieron en cuenta: Métodos Empíricos y Teóricos, Principios de la Educación Especial, las ideas de hombres célebres como: Martí, Fidel, Vigotsky y otros, lo que permitió ofrecer procedimientos metodológicos ordenados, con acciones concretas para resolver el problema de la socialización de estos alumnos .

  7. Solução concentrada de albumina eqüina na fluidoterapia em eqüinos com desidratação leve a moderada

    OpenAIRE

    Belli,C.B.; Michima,L.E.S.; Latorre,S.M.; Fernandes,W.R.

    2008-01-01

    Avaliou-se o efeito da solução concentrada de albumina eqüina diluída a 5% em solução fisiológica (SF) durante fluidoterapia em eqüinos, após indução de desidratação leve a moderada, utilizando-se cinco eqüinos adultos, sem alterações clínicas. Cada animal passou por dois protocolos de fluidoterapia: apenas com SF (metade sob pressão e metade em fluxo contínuo - grupo-controle); com solução de albumina eqüina e SF (apenas em fluxo contínuo - grupo experimental). Avaliaram-se peso, exame físic...

  8. Deterioro cognitivo leve: Encuesta sobre actitudes de médicos especialistas y generalistas Mild cognitive impairment: Survey of attitudes of specialists and general physicians

    Directory of Open Access Journals (Sweden)

    Cecilia M. Serrano

    2007-02-01

    Full Text Available El deterioro cognitivo leve es una entidad caracterizada por el compromiso predominante de la memoria en ausencia de trastorno funcional. Ha sido asociado a un período predemencial de la enfermedad de Alzheimer. Sin embargo, se considera que otras áreas cognitivas pueden verse afectadas, pudiendo implicar también otras etiologías. Así, algunos profesionales lo consideran un término etiológico, dirigido hacia la enfermedad de Alzheimer y otros un complejo sindromático, incluyendo varias enfermedades. Otro factor agregado que generó confusión ha sido el porcentaje de conversión a demencia. El objetivo de nuestro trabajo fue evaluar la opinión médica sobre el deterioro cognitivo leve y los problemas que genera en la práctica diaria. Se adaptó el cuestionario sobre deterioro cognitivo leve de Dubois y col, 2003; 24 médicos expertos en demencia de Argentina y Brasil (16 neurólogos y 8 psiquiatras y 30 médicos generalistas aceptaron responder al mismo. Los resultados muestran que el 92% de los médicos expertos piensa que es una entidad heterogénea, no la limitan a un estadio predemencia de la enfermedad de Alzheimer; y el 63% refieren que puede empeorar. El 83% de los expertos inician tratamiento específico utilizando preferentemente anticolinesterásicos, memantine y vitamina E. La vasta mayoría de médicos considera al deterioro cognitivo leve como una entidad sindromática, que no está limitada a la enfermedad de Alzheimer; pero sin embargo, inicia tratamiento con drogas dirigidas hacia ella. La ambigüedad existente hace necesario estandarizar definiciones y reconceptualizar la enfermedad de Alzheimer en su estadio pre-demencia.Mild cognitive impairment (MCI refers to persons who are slightly cognitively impaired for age but do not meet the criteria for dementia. MCI has been related to a pre-dementia stage of Alzheimer&'s disease (AD. However, other possible diagnoses such as cerebro-vascular disease, frontotemporal

  9. Comparison of evacuation methods used in the Netherlands and the USACE Dam and Levee Safety Programs for the Natomas Basin (CA

    Directory of Open Access Journals (Sweden)

    Kolen B. (Bas

    2016-01-01

    Full Text Available Both in the USA and in the Netherlands, extensive studies on approaches for identifying flood risks (the combination of levee failure probabilities and consequences are ongoing. A related topic concerns evacuation and emergency management (EEM. The magnitude of life loss is directly influenced by the effectiveness of EEM. Different models can be used to define the effectiveness of evacuation. The main objective of this study is to compare Dutch and American methods for evacuation as part of flood risk management strategies for a number of case studies in the US. A second, additional objective is to explore how approaches for EEM that have been recently developed in the Netherlands, can be applied in the United States. This research shows the benefits and limitations for the application of different types of models. This research contributes to the improvement of methods for emergency management, in the Netherlands, the US and other countries.

  10. A cultura do outro em Histórias de leves enganos e parecenças, de Conceição Evaristo

    Directory of Open Access Journals (Sweden)

    Nivana Ferreira da Silva

    2018-01-01

    Full Text Available Con base en los estudios culturales, específicamente en los debates relacionados a las formas como la cultura considerada hegemónica se configuró como tal, este artículo trae una discusión en torno a la constitución del canon literario, teniendo en cuenta lo que es dejado al margen de éste, especialmente en relación a las cuestiones raciales y de género. En ese sentido, consideramos ejemplar para nuestra reflexión la literatura de autoría negra y femenina, y analizamos el trabajo de Conceição Evaristo, a partir de su libro Histórias de leves enganos e pareenças (2016, objeto cultural emblemático para la problematización presentada.

  11. Concreto Leve Autoadensável: avaliação da influência da argila expandida no processo de dosagem e nas propriedades do concreto

    OpenAIRE

    José Wilson Assunção

    2016-01-01

    Esta tese aborda as influências do agregado leve na dosagem, características físicas e mecânicas de concreto autoadensável (CAA) quando na fração de graúdo da mistura, substitui-se parte do volume absoluto da brita de basalto (máx 19 mm) pelo volume equivalente de argila expandida brasileira (máx 12,7 mm). O fato de conhecer as implicações na reologia do CAA, provocadas pelo uso conjunto de agregados com características físicas distintas e, apresentar este tipo de concreto como uma alternativ...

  12. RESERVOIR CHARACTERIZATION OF THE LOWER GREEN RIVER FORMATION, SOUTHWEST UINTA BASIN, UTAH

    Energy Technology Data Exchange (ETDEWEB)

    S. Robert Bereskin

    2003-02-11

    Anastamosing, low gradient distributary channels produce {approx}30 gravity, paraffinic oils from the Middle Member of the lacustrine Eocene Green River Formation in the south-central portion of the Uinta Basin. This localized depocenter was situated along the fluctuating southern shoreline of Lake Uinta, where complex deposits of marginal-lacustrine to lower delta plain accumulations are especially characteristic. The Middle Member contains several fining-upward parasequences that can be recognized in outcrop, core, and downhole logs. Each parasequence is about 60 to 120 feet thick and consists of strata deposited during multiple lake level fluctuations that approach 30 to 35 feet in individual thickness. Such parasequences represent 300,000-year cycles based on limited absolute age dating. The subaerial to subaqueous channels commonly possess an erosional base and exhibit a fining upward character. Accordingly, bedding features commonly range from large-scale trough and planar cross bedding or lamination at the base, to a nonreservoir, climbing ripple assemblage near the uppermost reservoir boundary. The best reservoir quality occurs within the laminated to cross-stratified portions, and the climbing ripple phase usually possesses more deleterious micas and/or detrital clays. Diagenesis also exerts a major control on reservoir quality. Certain sandstones were cemented by an early, iron-poor calcite cement, which can be subsequently leached. Secondary intergranular porosity (up to 20%) is largely responsible for the 10 -100 millidarcy rock, which represents petrophysical objectives for both primary and secondary production. Otherwise, intense compaction, silicic and iron-rich carbonate cements, and authigenic clays serve to reduce reservoir quality to marginal economic levels.

  13. Simulation of Reservoir Sediment Flushing of the Three Gorges Reservoir Using an Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Xueying Li

    2016-05-01

    Full Text Available Reservoir sedimentation and its effect on the environment are the most serious world-wide problems in water resources development and utilization today. As one of the largest water conservancy projects, the Three Gorges Reservoir (TGR has been controversial since its demonstration period, and sedimentation is the major concern. Due to the complex physical mechanisms of water and sediment transport, this study adopts the Error Back Propagation Training Artificial Neural Network (BP-ANN to analyze the relationship between the sediment flushing efficiency of the TGR and its influencing factors. The factors are determined by the analysis on 1D unsteady flow and sediment mathematical model, mainly including reservoir inflow, incoming sediment concentration, reservoir water level, and reservoir release. Considering the distinguishing features of reservoir sediment delivery in different seasons, the monthly average data from 2003, when the TGR was put into operation, to 2011 are used to train, validate, and test the BP-ANN model. The results indicate that, although the sample space is quite limited, the whole sediment delivery process can be schematized by the established BP-ANN model, which can be used to help sediment flushing and thus decrease the reservoir sedimentation.

  14. A New Method for Fracturing Wells Reservoir Evaluation in Fractured Gas Reservoir

    Directory of Open Access Journals (Sweden)

    Jianchun Guo

    2014-01-01

    Full Text Available Natural fracture is a geological phenomenon widely distributed in tight formation, and fractured gas reservoir stimulation effect mainly depends on the communication of natural fractures. Therefore it is necessary to carry out the evaluation of this reservoir and to find out the optimal natural fractures development wells. By analyzing the interactions and nonlinear relationships of the parameters, it establishes three-level index system of reservoir evaluation and proposes a new method for gas well reservoir evaluation model in fractured gas reservoir on the basis of fuzzy logic theory and multilevel gray correlation. For this method, the Gaussian membership functions to quantify the degree of every factor in the decision-making system and the multilevel gray relation to determine the weight of each parameter on stimulation effect. Finally through fuzzy arithmetic operator between multilevel weights and fuzzy evaluation matrix, score, rank, the reservoir quality, and predicted production will be gotten. Result of this new method shows that the evaluation of the production coincidence rate reaches 80%, which provides a new way for fractured gas reservoir evaluation.

  15. Channel identification machines.

    Science.gov (United States)

    Lazar, Aurel A; Slutskiy, Yevgeniy B

    2012-01-01

    We present a formal methodology for identifying a channel in a system consisting of a communication channel in cascade with an asynchronous sampler. The channel is modeled as a multidimensional filter, while models of asynchronous samplers are taken from neuroscience and communications and include integrate-and-fire neurons, asynchronous sigma/delta modulators and general oscillators in cascade with zero-crossing detectors. We devise channel identification algorithms that recover a projection of the filter(s) onto a space of input signals loss-free for both scalar and vector-valued test signals. The test signals are modeled as elements of a reproducing kernel Hilbert space (RKHS) with a Dirichlet kernel. Under appropriate limiting conditions on the bandwidth and the order of the test signal space, the filter projection converges to the impulse response of the filter. We show that our results hold for a wide class of RKHSs, including the space of finite-energy bandlimited signals. We also extend our channel identification results to noisy circuits.

  16. Channel Identification Machines

    Directory of Open Access Journals (Sweden)

    Aurel A. Lazar

    2012-01-01

    Full Text Available We present a formal methodology for identifying a channel in a system consisting of a communication channel in cascade with an asynchronous sampler. The channel is modeled as a multidimensional filter, while models of asynchronous samplers are taken from neuroscience and communications and include integrate-and-fire neurons, asynchronous sigma/delta modulators and general oscillators in cascade with zero-crossing detectors. We devise channel identification algorithms that recover a projection of the filter(s onto a space of input signals loss-free for both scalar and vector-valued test signals. The test signals are modeled as elements of a reproducing kernel Hilbert space (RKHS with a Dirichlet kernel. Under appropriate limiting conditions on the bandwidth and the order of the test signal space, the filter projection converges to the impulse response of the filter. We show that our results hold for a wide class of RKHSs, including the space of finite-energy bandlimited signals. We also extend our channel identification results to noisy circuits.

  17. Uso de agregado leve de EVA em contrapiso argamassado para isolamento ao ruído de impacto em edificações residenciais

    Directory of Open Access Journals (Sweden)

    Bernardo Fonseca Tutikian

    Full Text Available Resumo O copolímero etileno acetato de vinila (EVA é largamente utilizado na indústria calçadista. Entretanto, a geração de resíduos no processo de fabricação é bastante significativa. Com a implementação da norma de desempenho, NBR 15575, os projetos de construções habitacionais devem atender aos níveis de desempenho exigidos. Dentre os requisitos prescritos pela norma está a isolação ao ruído de impacto entre pisos, a qual pode ser otimizada com a utilização de materiais de baixa massa específica. Nesse contexto, este artigo visa desenvolver uma argamassa leve, a partir da incorporação de EVA proveniente da indústria calçadista, a ser utilizada como contrapiso para isolamento acústico. Para tanto, fez-se um estudo por meio de ensaios de resistência à compressão e à tração, bem como nível de pressão sonora de impacto padronizado ponderado, realizado em câmara normatizada. Foram desenvolvidos cinco traços, com proporções de 20%, 40%, 60%, 80% e 100% de substituição da agregado miúdo por EVA, além do contrapiso convencional. Foram moldadas placas de 1 m2 de contrapiso leve, e uma amostra representativa do tamanho da laje com 16 m2, as quais diferiram em 2 dB para o isolamento acústico. O traço com melhor desempenho proporcionou uma redução de 9 dB em relação ao contrapiso convencional, mostrando ser eficaz para utilização como isolante acústico.

  18. Sensitivity Analysis of Methane Hydrate Reservoirs: Effects of Reservoir Parameters on Gas Productivity and Economics

    Science.gov (United States)

    Anderson, B. J.; Gaddipati, M.; Nyayapathi, L.

    2008-12-01

    This paper presents a parametric study on production rates of natural gas from gas hydrates by the method of depressurization, using CMG STARS. Seven factors/parameters were considered as perturbations from a base-case hydrate reservoir description based on Problem 7 of the International Methane Hydrate Reservoir Simulator Code Comparison Study led by the Department of Energy and the USGS. This reservoir is modeled after the inferred properties of the hydrate deposit at the Prudhoe Bay L-106 site. The included sensitivity variables were hydrate saturation, pressure (depth), temperature, bottom-hole pressure of the production well, free water saturation, intrinsic rock permeability, and porosity. A two-level (L=2) Plackett-Burman experimental design was used to study the relative effects of these factors. The measured variable was the discounted cumulative gas production. The discount rate chosen was 15%, resulting in the gas contribution to the net present value of a reservoir. Eight different designs were developed for conducting sensitivity analysis and the effects of the parameters on the real and discounted production rates will be discussed. The breakeven price in various cases and the dependence of the breakeven price on the production parameters is given in the paper. As expected, initial reservoir temperature has the strongest positive effect on the productivity of a hydrate deposit and the bottom-hole pressure in the production well has the strongest negative dependence. Also resulting in a positive correlation is the intrinsic permeability and the initial free water of the formation. Negative effects were found for initial hydrate saturation (at saturations greater than 50% of the pore space) and the reservoir porosity. These negative effects are related to the available sensible heat of the reservoir, with decreasing productivity due to decreasing available sensible heat. Finally, we conclude that for the base case reservoir, the break-even price (BEP

  19. Improved characterization of reservoir behavior by integration of reservoir performances data and rock type distributions

    Energy Technology Data Exchange (ETDEWEB)

    Davies, D.K.; Vessell, R.K. [David K. Davies & Associates, Kingwood, TX (United States); Doublet, L.E. [Texas A& M Univ., College Station, TX (United States)] [and others

    1997-08-01

    An integrated geological/petrophysical and reservoir engineering study was performed for a large, mature waterflood project (>250 wells, {approximately}80% water cut) at the North Robertson (Clear Fork) Unit, Gaines County, Texas. The primary goal of the study was to develop an integrated reservoir description for {open_quotes}targeted{close_quotes} (economic) 10-acre (4-hectare) infill drilling and future recovery operations in a low permeability, carbonate (dolomite) reservoir. Integration of the results from geological/petrophysical studies and reservoir performance analyses provide a rapid and effective method for developing a comprehensive reservoir description. This reservoir description can be used for reservoir flow simulation, performance prediction, infill targeting, waterflood management, and for optimizing well developments (patterns, completions, and stimulations). The following analyses were performed as part of this study: (1) Geological/petrophysical analyses: (core and well log data) - {open_quotes}Rock typing{close_quotes} based on qualitative and quantitative visualization of pore-scale features. Reservoir layering based on {open_quotes}rock typing {close_quotes} and hydraulic flow units. Development of a {open_quotes}core-log{close_quotes} model to estimate permeability using porosity and other properties derived from well logs. The core-log model is based on {open_quotes}rock types.{close_quotes} (2) Engineering analyses: (production and injection history, well tests) Material balance decline type curve analyses to estimate total reservoir volume, formation flow characteristics (flow capacity, skin factor, and fracture half-length), and indications of well/boundary interference. Estimated ultimate recovery analyses to yield movable oil (or injectable water) volumes, as well as indications of well and boundary interference.

  20. INCREASING WATERFLOOD RESERVES IN THE WILMINGTON OIL FIELD THROUGH IMPROVED RESERVOIR CHARACTERIZATION AND RESERVOIR MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Scott Walker; Chris Phillips; Roy Koerner; Don Clarke; Dan Moos; Kwasi Tagbor

    2002-02-28

    This project increased recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs. Transferring technology so that it can be applied in other sections of the Wilmington Field and by operators in other slope and basin reservoirs is a primary component of the project. This project used advanced reservoir characterization tools, including the pulsed acoustic cased-hole logging tool, geologic three-dimensional (3-D) modeling software, and commercially available reservoir management software to identify sands with remaining high oil saturation following waterflood. Production from the identified high oil saturated sands was stimulated by recompleting existing production and injection wells in these sands using conventional means as well as a short radius redrill candidate. Although these reservoirs have been waterflooded over 40 years, researchers have found areas of remaining oil saturation. Areas such as the top sand in the Upper Terminal Zone Fault Block V, the western fault slivers of Upper Terminal Zone Fault Block V, the bottom sands of the Tar Zone Fault Block V, and the eastern edge of Fault Block IV in both the Upper Terminal and Lower Terminal Zones all show significant remaining oil saturation. Each area of interest was uncovered emphasizing a different type of reservoir characterization technique or practice. This was not the original strategy but was necessitated by the different levels of progress in each of the project activities.

  1. Influence of Large Reservoir Operation on Water-Levels and Flows in Reaches below Dam: Case Study of the Three Gorges Reservoir.

    Science.gov (United States)

    Yang, Yunping; Zhang, Mingjin; Zhu, Lingling; Liu, Wanli; Han, Jianqiao; Yang, Yanhua

    2017-11-15

    The Three Gorges Project (TGP) is the world's largest water conservation project. The post-construction low-flow water level at the same discharge below the dam has declined, but there remains disagreement over whether the flood level has increased. Measured water levels and upstream and downstream flow data from 1955 to 2016 show that, post-construction: (1) the low-flow water level at the same discharge decreased, and the lowest water level increased due to dry-season reservoir discharge; (2) the decline of the low-flow water level below the dam was less than the undercutting value of the flow channel of the river; (3) the flood level at the same discharge below the dam was slightly elevated, although peak water levels decreased; (4) flood characteristics changed from a high discharge-high flood level to a medium discharge - high flood level; and (5) an expected decline in the flood level downstream was not observed. Channel erosion and the adjustment of rivers and lakes tend to reduce flood levels, while river bed coarsening, vegetation, and human activities downstream increase the flood level. Although the flood control benefits of the Three Gorges Dam (TGD) and the upstream reservoirs are obvious, increased elevation of the downstream flood level remains a concern.

  2. Deciphering Depositional Signals in the Bed-Scale Stratigraphic Record of Submarine Channels

    Science.gov (United States)

    Sylvester, Z.; Covault, J. A.

    2017-12-01

    Submarine channels are important conduits of sediment transfer from rivers and shallow-marine settings into the deep sea. As such, the stratigraphic record of submarine-channel systems can store signals of past climate- and other environmental changes in their upstream sediment-source areas. This record is highly fragmented as channels are primarily locations of sediment bypass; channelized turbidity currents are likely to leave a more complete record in areas away from and above the thalweg. However, the link between the thick-bedded axial channel deposits that record a small number of flows and the much larger number of thin-bedded turbidites forming terrace- and levee deposits is poorly understood. We have developed a relatively simple two-dimensional model that, given a number of input flow parameters (mean velocity, grain size, duration of deposition, flow thickness), predicts the thickness and composition of the turbidite that is left behind in the channel and in the overbank areas. The model is based on a Rouse-type suspended sediment concentration profile and the Garcia-Parker entrainment function. In the vertical direction, turbidites tend to rapidly become thinner and finer-grained with height above thalweg, due to decreasing concentration. High near-thalweg concentrations result in thick axial beds. However, an increase in flow velocity can result in high entrainment and no deposition at the bottom of the channel, yet a thin layer of sand and mud is still deposited higher up on the channel bank. If channel thalwegs are largely in a bypass condition, relatively minor velocity fluctuations result in a few occasionally preserved thick beds in the axis, and numerous thin turbidites - and a more complete record - on the channel banks. We use near-seafloor data from the Niger Delta slope and an optimization algorithm to show how our model can be used to invert for likely flow parameters and match the bed thickness and grain size of 100 turbidites observed in a

  3. SEISMIC DETERMINATION OF RESERVOIR HETEROGENEITY; APPLICATION TO THE CHARACTERIZATION OF HEAVY OIL RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Matthias G. Imhof; James W. Castle

    2003-11-01

    The objective of the project is to examine how seismic and geologic data can be used to improve characterization of small-scale heterogeneity and their parameterization in reservoir models. The study is performed at West Coalinga Field in California. We continued our investigation on the nature of seismic reactions from heterogeneous reservoirs. We began testing our algorithm to infer parameters of object-based reservoir models from seismic data. We began integration of seismic and geologic data to determine the deterministic limits of conventional seismic data interpretation. Lastly, we began integration of seismic and geologic heterogeneity using stochastic models conditioned both on wireline and seismic data.

  4. DEVELOPMENT OF RESERVOIR CHARACTERIZATION TECHNIQUES AND PRODUCTION MODELS FOR EXPLOITING NATURALLY FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Wiggins; Raymon L. Brown; Faruk Civan; Richard G. Hughes

    2002-12-31

    For many years, geoscientists and engineers have undertaken research to characterize naturally fractured reservoirs. Geoscientists have focused on understanding the process of fracturing and the subsequent measurement and description of fracture characteristics. Engineers have concentrated on the fluid flow behavior in the fracture-porous media system and the development of models to predict the hydrocarbon production from these complex systems. This research attempts to integrate these two complementary views to develop a quantitative reservoir characterization methodology and flow performance model for naturally fractured reservoirs. The research has focused on estimating naturally fractured reservoir properties from seismic data, predicting fracture characteristics from well logs, and developing a naturally fractured reservoir simulator. It is important to develop techniques that can be applied to estimate the important parameters in predicting the performance of naturally fractured reservoirs. This project proposes a method to relate seismic properties to the elastic compliance and permeability of the reservoir based upon a sugar cube model. In addition, methods are presented to use conventional well logs to estimate localized fracture information for reservoir characterization purposes. The ability to estimate fracture information from conventional well logs is very important in older wells where data are often limited. Finally, a desktop naturally fractured reservoir simulator has been developed for the purpose of predicting the performance of these complex reservoirs. The simulator incorporates vertical and horizontal wellbore models, methods to handle matrix to fracture fluid transfer, and fracture permeability tensors. This research project has developed methods to characterize and study the performance of naturally fractured reservoirs that integrate geoscience and engineering data. This is an important step in developing exploitation strategies for

  5. Impact of a Thermocline on Water Dynamics in Reservoirs – Dobczyce Reservoir Case

    Directory of Open Access Journals (Sweden)

    Hachaj Paweł S.

    2017-06-01

    Full Text Available While modeling water dynamics in dam reservoirs, it is usually assumed that the flow involves the whole water body. It is true for shallow reservoirs (up to several meters of depth but may be false for deeper ones. The possible presence of a thermocline creates an inactive bottom layer that does not move, causing all the discharge to be carried by the upper strata. This study compares the results of hydrodydynamic simulations performed for the whole reservoir to the ones carried out for the upper strata only. The validity of a non-stratified flow approximation is then discussed.

  6. Channel plate for DNA sequencing

    Science.gov (United States)

    Douthart, Richard J.; Crowell, Shannon L.

    1998-01-01

    This invention is a channel plate that facilitates data compaction in DNA sequencing. The channel plate has a length, a width and a thickness, and further has a plurality of channels that are parallel. Each channel has a depth partially through the thickness of the channel plate. Additionally an interface edge permits electrical communication across an interface through a buffer to a deposition membrane surface.

  7. Nanoscale Vacuum Channel Transistor.

    Science.gov (United States)

    Han, Jin-Woo; Moon, Dong-Il; Meyyappan, M

    2017-04-12

    Vacuum tubes that sparked the electronics era had given way to semiconductor transistors. Despite their faster operation and better immunity to noise and radiation compared to the transistors, the vacuum device technology became extinct due to the high power consumption, integration difficulties, and short lifetime of the vacuum tubes. We combine the best of vacuum tubes and modern silicon nanofabrication technology here. The surround gate nanoscale vacuum channel transistor consists of sharp source and drain electrodes separated by sub-50 nm vacuum channel with a source to gate distance of 10 nm. This transistor performs at a low voltage (3 microamperes). The nanoscale vacuum channel transistor can be a possible alternative to semiconductor transistors beyond Moore's law.

  8. Chaos in quantum channels

    Science.gov (United States)

    Hosur, Pavan; Qi, Xiao-Liang; Roberts, Daniel A.; Yoshida, Beni

    2016-02-01

    We study chaos and scrambling in unitary channels by considering their entanglement properties as states. Using out-of-time-order correlation functions to diagnose chaos, we characterize the ability of a channel to process quantum information. We show that the generic decay of such correlators implies that any input subsystem must have near vanishing mutual information with almost all partitions of the output. Additionally, we propose the negativity of the tripartite information of the channel as a general diagnostic of scrambling. This measures the delocalization of information and is closely related to the decay of out-of-time-order correlators. We back up our results with numerics in two non-integrable models and analytic results in a perfect tensor network model of chaotic time evolution. These results show that the butterfly effect in quantum systems implies the information-theoretic definition of scrambling.

  9. CANDU fuel channels

    International Nuclear Information System (INIS)

    Coleman, C.E.; Cheadle, B.A.

    1997-01-01

    The service life of CANDU fuel channels is determined by the component that has to withstand the most severe conditions, the Zr-2.5Nb pressure tube. The latest fuel channels are expected to have a lifetime of over 30 years. The properties that control service life are fracture and deformation. For fracture, a defence-in-depth approach is used - preventing crack initiation and invoking leak-before-break. Confidence in the serviceability of fuel channels is based on current knowledge of the state of health of the components evaluated by surveillance. Degradation of properties with service is slow, allowing sufficient time to judge and act when end-of-life is reached. Methods for improving the properties of components are outlined. (author)

  10. Estimates of Nitrogen Removal in U.S. Streams and Reservoirs from the SPARROW Watershed Model

    Science.gov (United States)

    Alexander, R. B.; Smith, R. A.; Schwarz, G. E.; Nolan, J. V.; Boyer, E. W.

    2003-12-01

    Greater understanding is needed of the biotic and abiotic processes that remove nitrogen (N) from streams and reservoirs to quantify transport to downstream coastal waters where eutrophication is a major concern. Recent studies have improved estimates of N removal rates (e.g., denitrification, biological uptake) over small spatial scales in low-order streams. However, limited knowledge of the factors that explain the large variation in literature removal rates has made it difficult to accurately predict N transport through the range of stream and reservoir sizes that link sources to downstream waters. Spatially referenced watershed models (SPARROW) have been used to statistically estimate long-term mean-annual rates of total nitrogen removal in streams and reservoirs over large spatial scales. These rates are estimated as a function of physical and hydraulic properties (channel depth, water travel time) that influence the contact and exchange of water with benthic sediment. We recently refined our SPARROW model structure with expanded descriptions of climatic, topographic, and other surficial features of terrestrial and aquatic landscapes. We find that the net rates of N removal decline from about 0.3 day-1 of water travel time in streams with depths less than 0.5 meters to negligible quantities in large rivers (greater than 4 meters). These rates are generally consistent with those of earlier regional and national SPARROW models and with measured rates from the literature (adjusted for water travel time) over the reported range of stream depths. A settling velocity of approximately 8 meters year-1 is estimated for lakes and reservoirs and agrees well with literature rates for lakes where denitrification is the predominant removal process. We applied these removal rates within the SPARROW stream and reservoir network to estimate the regional-scale N transport and delivery to U.S. coastal waters.

  11. Adsorption of hydrocarbons in chalk reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, L.

    1996-12-31

    The present work is a study on the wettability of hydrocarbon bearing chalk reservoirs. Wettability is a major factor that influences flow, location and distribution of oil and water in the reservoir. The wettability of the hydrocarbon reservoirs depends on how and to what extent the organic compounds are adsorbed onto the surfaces of calcite, quartz and clay. Organic compounds such as carboxylic acids are found in formation waters from various hydrocarbon reservoirs and in crude oils. In the present investigation the wetting behaviour of chalk is studied by the adsorption of the carboxylic acids onto synthetic calcite, kaolinite, quartz, {alpha}-alumina, and chalk dispersed in an aqueous phase and an organic phase. In the aqueous phase the results clearly demonstrate the differences between the adsorption behaviour of benzoic acid and hexanoic acid onto the surfaces of oxide minerals and carbonates. With NaCl concentration of 0.1 M and with pH {approx_equal} 6 the maximum adsorption of benzoic acid decreases in the order: quartz, {alpha}-alumina, kaolinite. For synthetic calcite and chalk no detectable adsorption was obtaind. In the organic phase the order is reversed. The maximum adsorption of benzoic acid onto the different surfaces decreases in the order: synthetic calcite, chalk, kaolinite and quartz. Also a marked difference in adsorption behaviour between probes with different functional groups onto synthetic calcite from organic phase is observed. The maximum adsorption decreases in the order: benzoic acid, benzyl alcohol and benzylamine. (au) 54 refs.

  12. Accounting for Greenhouse Gas Emissions from Reservoirs ...

    Science.gov (United States)

    Nearly three decades of research has demonstrated that the impoundment of rivers and the flooding of terrestrial ecosystems behind dams can increase rates of greenhouse gas emission, particularly methane. The 2006 IPCC Guidelines for National Greenhouse Gas Inventories includes a methodology for estimating methane emissions from flooded lands, but the methodology was published as an appendix to be used as a ‘basis for future methodological development’ due to a lack of data. Since the 2006 Guidelines were published there has been a 6-fold increase in the number of peer reviewed papers published on the topic including reports from reservoirs in India, China, Africa, and Russia. Furthermore, several countries, including Iceland, Switzerland, and Finland, have developed country specific methodologies for including flooded lands methane emissions in their National Greenhouse Gas Inventories. This presentation will include a review of the literature on flooded land methane emissions and approaches that have been used to upscale emissions for national inventories. We will also present ongoing research in the United States to develop a country specific methodology. In the U.S., research approaches include: 1) an effort to develop predictive relationships between methane emissions and reservoir characteristics that are available in national databases, such as reservoir size and drainage area, and 2) a national-scale probabilistic survey of reservoir methane em

  13. Probing magma reservoirs to improve volcano forecasts

    Science.gov (United States)

    Lowenstern, Jacob B.; Sisson, Thomas W.; Hurwitz, Shaul

    2017-01-01

    When it comes to forecasting eruptions, volcano observatories rely mostly on real-time signals from earthquakes, ground deformation, and gas discharge, combined with probabilistic assessments based on past behavior [Sparks and Cashman, 2017]. There is comparatively less reliance on geophysical and petrological understanding of subsurface magma reservoirs.

  14. Fourteenth workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Miller, F.G.; Brigham, W.E.; Cook, J.W.

    1989-01-01

    The Fourteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 24--26, 1989. Major areas of discussion include: (1) well testing; (2) various field results; (3) geoscience; (4) geochemistry; (5) reinjection; (6) hot dry rock; and (7) numerical modelling. For these workshop proceedings, individual papers are processed separately for the Energy Data Base.

  15. Fourteenth workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Miller, F.G.; Brigham, W.E.; Cook, J.W.

    1989-12-31

    The Fourteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 24--26, 1989. Major areas of discussion include: (1) well testing; (2) various field results; (3) geoscience; (4) geochemistry; (5) reinjection; (6) hot dry rock; and (7) numerical modelling. For these workshop proceedings, individual papers are processed separately for the Energy Data Base.

  16. Sidi Saâd reservoir

    African Journals Online (AJOL)

    DR. NJ TONUKARI

    2012-01-12

    Jan 12, 2012 ... with environmental factors in a semi arid area: Sidi. Saâd reservoir .... between changes in environmental parameters, biological factors and ..... Dinophyceae. Copepoda. Anabaena sp. Gonyaulax sp. Acanthocyclops robustus Acanthocyclops viridis. Chroococcus sp. Gonyaulax spinifera. Gloeothece sp.

  17. Freshwater reservoir effect variability in Northern Germany

    DEFF Research Database (Denmark)

    Philippsen, Bente; Heinemeier, Jan

    2012-01-01

    Kayhude at the river Alster and Schlamersdorf at the river Trave, both in Schleswig-Holstein, Northern Germany. Measurements on modern materials from these rivers may not give a single reservoir age correction that can be applied to archaeological samples, but they will show the order of magnitude...

  18. Borehole radar modeling for reservoir monitoring applications

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2010-01-01

    The use of down-hole sensors and remotely controlled valves in wells provide enormous benefits to reservoir management and oil production. We suggest borehole radar measurements as a promising technique capable of monitoring the arrival of undesired fluids in the proximity of production wells. The

  19. Do cyanobacterial picoplankton exist in eutrophic reservoirs?

    Czech Academy of Sciences Publication Activity Database

    Komárková, Jaroslava

    2002-01-01

    Roč. 28, - (2002), s. 497-500 ISSN 0368-0770 R&D Projects: GA AV ČR IBS6017004; GA AV ČR IAA6017803; GA AV ČR KSK2005601 Keywords : reservoir * colonial picocynobacteria Subject RIV: DA - Hydrology ; Limnology

  20. Novel Synechococcus genomes reconstructed from freshwater reservoirs

    Czech Academy of Sciences Publication Activity Database

    Cabello-Yeves, P.J.; Haro-Moreno, J.M.; Martin-Cuadrado, A.B.; Ghai, Rohit; Picazo, A.; Camacho, A.; Rodriguez-Valera, F.

    2017-01-01

    Roč. 8, June (2017), č. článku 1151. ISSN 1664-302X R&D Projects: GA ČR(CZ) GA17-04828S Institutional support: RVO:60077344 Keywords : Synechococcus * picocyanobacteria * freshwater reservoirs * metagenomics * abundance Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.076, year: 2016

  1. Fifteenth workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The Fifteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 23--25, 1990. Major topics included: DOE's geothermal research and development program, well testing, field studies, geosciences, geysers, reinjection, tracers, geochemistry, and modeling.

  2. Sinusoidal cycling swimming pattern of reservoir fishes

    Czech Academy of Sciences Publication Activity Database

    Čech, Martin; Kubečka, Jan

    2002-01-01

    Roč. 61, č. 2 (2002), s. 456-471 ISSN 0022-1112 R&D Projects: GA AV ČR IAA6017901; GA AV ČR IAA6017201; GA ČR GA206/02/0520 Keywords : sinusoidal swimming * echosounder * reservoir Subject RIV: EH - Ecology, Behaviour Impact factor: 1.186, year: 2002

  3. Can Dams and Reservoirs Cause Earthquakes?

    Indian Academy of Sciences (India)

    indirect investigations of these regions are subject to inevitable multiple interpretations. Still, a measure of understanding about reservoir induced earthquakes has been achieved. It is my aim to put the phenomenon in a perspective on this basis. I saw the Koyna Earthquake Recorded. Koyna earthquake of December 10, ...

  4. Movement of Sediment Associated With Lowered Reservoir Levels in the Rio La Venta Arm of the Presa Netzahualcoyotl, Chiapas, Mexico

    Science.gov (United States)

    Hilton, S.; de La Fuente, J.; Lisle, T. E.; Velasquez, J.; Allison, B.; Olson, B.; Quinones, R.

    2003-12-01

    of fresh bars. Transverse profiles showed a flat bed with multiple submerged channels, consistent with high sediment mobility. Sediment stored in exposed bars up to 4 meters in height consisted of light colored sand beds alternating with dark organic-rich silt and clay beds ranging from a few centimeters to 50 cm in thickness. These beds were deposited in fluvial and lacustrine environments respectively. We conclude that: a) Lowering of the reservoir allowed sediment to be transported out of the canyon; b) Long periods of inundation of the canyon allow accumulation of very fine sediment (clay/silt/organic) which may affect fish habitat; c) Sediment accumulation in the canyon appears to be a balance between accumulation at high reservoir levels and removal at lower levels. Continuing research will examine: past reservoir levels; future changes in channel geometry; sediment sources, particularly recently burned areas adjacent to the reservoir; and fish populations and habitat. These studies will improve our understanding of sedimentation patterns and processes and our ability to make management recommendations for Netzahualcoyotl reservoir.

  5. Gas accumulations in Oligocene-Miocene reservoirs in the Alpine Foreland Basin (Austria): evidence for gas mixing and gas degradation

    Science.gov (United States)

    Pytlak, L.; Gross, D.; Sachsenhofer, R. F.; Bechtel, A.; Linzer, H.-G.

    2017-09-01

    Two petroleum systems are present in the eastern (Austrian) sector of the Alpine Foreland Basin. Whereas oil and thermogenic gas in Mesozoic and Eocene reservoir rocks have been generated beneath the Alps in Lower Oligocene source rocks, relative dry gas in Oligocene-Miocene clastic rocks deposited in the deep marine basin-axial channel system (Puchkirchen Channel) is interpreted as microbial in origin. Detailed investigations of the molecular and isotope composition of 87 gas samples from 86 wells, representing all producing fields with Oligocene and Miocene reservoir rocks, suggest that the presence of pure microbial gas is rare and limited mainly to the northern basin flank (e.g., KK field). All other fields contain varying amounts of thermogenic gas, which has been generated from a source rock with oil-window maturity. A relation with the underlying thermogenic petroleum system is obvious. Upward migration occurred along discrete fault zones (e.g., H field) or through low-permeability caprocks. Local erosion of Lower Oligocene sediments, the principal seal for the thermogenic petroleum system, as well as a high percentage of permeable rocks within the Puchkirchen Channel favored upward migration and mixing of thermogenic and microbial gas. All gas samples in Oligocene-Miocene reservoirs are biodegraded. Biodegradation and the formation of secondary microbial gas resulted in gas drying. Therefore, the gas samples analyzed in this study are relative dry, despite significant contributions of thermogenic hydrocarbons. Biodegradation probably continues at present time. The degree of biodegradation, however, decreases with depth.

  6. Improved oil recovery in fluvial dominated deltaic reservoirs of Kansas - Near-term. Annual report, June 18, 1993--June 18, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Green, D.W.; Willhite, G.P.

    1995-10-01

    Common oil field problems exist in fluvial dominated deltaic reservoirs in Kansas. The problems are poor waterflood sweep and lack of reservoir management. The poor waterflood sweep efficiency is due to (1) reservoir heterogeneity, (2) channeling of injected water through high permeability zones or fractures, and (3) clogging of water injection wells with solids as a result of poor water quality. In many instances the lack of reservoir management is due to lack of (1) data collection and organization, (2) integrated analysis of existing data by geological and engineering personnel, and (3) identification of optimum recovery techniques. Two demonstration sites operated by different independent oil operators are involved in the project. The Nelson Lease (an existing waterflood) is located in Allen County, Kansas in the N.E. Savonburg Field and is operated by James E. Russell Petroleum, Inc. The Stewart Field (on the latter stage of primary production) is located in Finney County, Kansas and is operated by Sharon Resources, Inc. The objective is to increase recovery efficiency and economics in these type of reservoirs. The technologies being applied to increase waterflood sweep efficiency are (1) in situ permeability modification treatments, (2) infill drilling, (3) pattern changes, and (4) air flotation to improve water quality. The technologies being applied to improve reservoir management are (1) database development, (2) reservoir simulation, (3) transient testing, (4) database management, and (5) integrated geological and engineering analysis.

  7. Environmental impact from pollutant action in the Billings Reservoir in Sao Paulo metropolitan area - Brazil

    International Nuclear Information System (INIS)

    Fujita, S.; Braghin, P.L.

    1989-01-01

    The ELETROPAULO Electricity from Sao Paulo S/A covers 74 municipal district of the State with electric power, signifying 26% of the energy consumed in Brazil. This paper presents problems with the aquatic plants proliferation and the methods used for their control in the ELETROPAULO hydraulic system, compound by generators plants, channels and reservoirs. The main consequences of their evolution and the advantage and disadvantage of the used methods are mentioned. These plant proliferation cause damages for the neighbour population, with some social and sanitary re flexion, and for the Company operation. Considerations for an improvement of the control methods are also cited. (C.G.C.). 1 fig

  8. Analysis of Sedimentation in Wonogiri Reservoir

    Directory of Open Access Journals (Sweden)

    Tri Joko Inti Budi Santosa

    2016-01-01

    Full Text Available The Wonogiri reservoir which has 730 million cubic meters of total storage, 90 square kilometers of water area, and 1260 square kilometers of catchment area, is located in the Wonogiri Regency, Central Java Province. It was first established in 1981 and began its operation in 1982 with the expectation that it would last for about 100 years. Today (2002 the reservoir has got a serious problem of sedimentation. The sedimentation is so large that it would decrease the capacity storage of the reservoir and would shorten the length of operation. Therefore, it is necessary to predict the sediment that comes into the reservoir. This research would be based on the total sediment calculation of the sedimentation, through some methods, such as echo sounding measured data, land erosion (USLE, the calculation of the sediment in rivers. This research calculates the sediment capacities based on the water flow data and the sediment rating curves in rivers of Keduang, Tirtomoyo, Temon, upstream reach of Bengawan Solo, Alang, and Wuryantoro. The suspended load was calculated based on the sediment rating curves, whereas the bed load was computed as the percentage of the suspended load. The sum of both calculation results would be the total sediment. The calculation result showed that the total sediment which has come into the reservoir is 6.68 million cubic meters per year. As a comparison, the writer noted that the former researcher using echo sounding method done by the Faculty of Geography of the Universitas Gadjah Mada in 1985, it found that the total sediment capacity which came into the reservoir was 6.60 million cubic meters per year or 5.40 mm per year of sheet erosion. The other research using echo sounding method done by JICA in 2000 found that the total sediment which had come into the reservoir was 4.50 million cubic meters per year or 3.50 mm per year of sheet erosion. By knowing the results of calculation of the total sediment, we can learn that

  9. Performance Analysis of Depleted Oil Reservoirs for Underground Gas Storage

    Directory of Open Access Journals (Sweden)

    Dr. C.I.C. Anyadiegwu

    2014-02-01

    Full Text Available The performance of underground gas storage in depleted oil reservoir was analysed with reservoir Y-19, a depleted oil reservoir in Southern region of the Niger Delta. Information on the geologic and production history of the reservoir were obtained from the available field data of the reservoir. The verification of inventory was done to establish the storage capacity of the reservoir. The plot of the well flowing pressure (Pwf against the flow rate (Q, gives the deliverability of the reservoir at various pressures. Results of the estimated properties signified that reservoir Y-19 is a good candidate due to its storage capacity and its flow rate (Q of 287.61 MMscf/d at a flowing pressure of 3900 psig

  10. AUTOMATED TECHNIQUE FOR FLOW MEASUREMENTS FROM MARIOTTE RESERVOIRS.

    Science.gov (United States)

    Constantz, Jim; Murphy, Fred

    1987-01-01

    The mariotte reservoir supplies water at a constant hydraulic pressure by self-regulation of its internal gas pressure. Automated outflow measurements from mariotte reservoirs are generally difficult because of the reservoir's self-regulation mechanism. This paper describes an automated flow meter specifically designed for use with mariotte reservoirs. The flow meter monitors changes in the mariotte reservoir's gas pressure during outflow to determine changes in the reservoir's water level. The flow measurement is performed by attaching a pressure transducer to the top of a mariotte reservoir and monitoring gas pressure changes during outflow with a programmable data logger. The advantages of the new automated flow measurement techniques include: (i) the ability to rapidly record a large range of fluxes without restricting outflow, and (ii) the ability to accurately average the pulsing flow, which commonly occurs during outflow from the mariotte reservoir.

  11. Reservoir Cathode for Electric Space Propulsion, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a hollow reservoir cathode to improve performance in ion and Hall thrusters. We will adapt our existing reservoir cathode technology to this purpose....

  12. Reservoir pressure evolution model during exploration drilling

    Directory of Open Access Journals (Sweden)

    Korotaev B. A.

    2017-03-01

    Full Text Available Based on the analysis of laboratory studies and literature data the method for estimating reservoir pressure in exploratory drilling has been proposed, it allows identify zones of abnormal reservoir pressure in the presence of seismic data on reservoir location depths. This method of assessment is based on developed at the end of the XX century methods using d- and σ-exponentials taking into account the mechanical drilling speed, rotor speed, bit load and its diameter, lithological constant and degree of rocks' compaction, mud density and "regional density". It is known that in exploratory drilling pulsation of pressure at the wellhead is observed. Such pulsation is a consequence of transferring reservoir pressure through clay. In the paper the mechanism for transferring pressure to the bottomhole as well as the behaviour of the clay layer during transmission of excess pressure has been described. A laboratory installation has been built, it has been used for modelling pressure propagation to the bottomhole of the well through a layer of clay. The bulge of the clay layer is established for 215.9 mm bottomhole diameter. Functional correlation of pressure propagation through the layer of clay has been determined and a reaction of the top clay layer has been shown to have bulge with a height of 25 mm. A pressure distribution scheme (balance has been developed, which takes into account the distance from layers with abnormal pressure to the bottomhole. A balance equation for reservoir pressure evaluation has been derived including well depth, distance from bottomhole to the top of the formation with abnormal pressure and density of clay.

  13. Enhancement of seismic monitoring in hydrocarbon reservoirs

    Science.gov (United States)

    Caffagni, Enrico; Bokelmann, Götz

    2017-04-01

    Hydraulic Fracturing (HF) is widely considered as one of the most significant enablers of the successful exploitation of hydrocarbons in North America. Massive usage of HF is currently adopted to increase the permeability in shale and tight-sand deep reservoirs, despite the economical downturn. The exploitation success is less due to the subsurface geology, but in technology that improves exploration, production, and decision-making. This includes monitoring of the reservoir, which is vital. Indeed, the general mindset in the industry is to keep enhancing seismic monitoring. It allows understanding and tracking processes in hydrocarbon reservoirs, which serves two purposes, a) to optimize recovery, and b) to help minimize environmental impact. This raises the question of how monitoring, and especially seismic techniques could be more efficient. There is a pressing demand from seismic service industry to evolve quickly and to meet the oil-gas industry's changing needs. Nonetheless, the innovative monitoring techniques, to achieve the purpose, must enhance the characterization or the visualization of a superior-quality images of the reservoir. We discuss recent applications of seismic monitoring in hydrocarbon reservoirs, detailing potential enhancement and eventual limitations. The aim is to test the validity of these seismic monitoring techniques, qualitatively discuss their potential application to energy fields that are not only limited to HF. Outcomes from our investigation may benefit operators and regulators in case of future massive HF applications in Europe, as well. This work is part of the FracRisk consortium (www.fracrisk.eu), funded by the Horizon2020 research programme, whose aims is to help minimize the environmental footprint of the shale-gas exploration and exploitation.

  14. MITOCHONDRIAL BKCa CHANNEL

    Directory of Open Access Journals (Sweden)

    Enrique eBalderas

    2015-03-01

    Full Text Available Since its discovery in a glioma cell line 15 years ago, mitochondrial BKCa channel (mitoBKCa has been studied in brain cells and cardiomyocytes sharing general biophysical properties such as high K+ conductance (~300 pS, voltage-dependency and Ca2+-sensitivity. Main advances in deciphering the molecular composition of mitoBKCa have included establishing that it is encoded by the Kcnma1 gene, that a C-terminal splice insert confers mitoBKCa ability to be targeted to cardiac mitochondria, and evidence for its potential coassembly with β subunits. Notoriously, β1 subunit directly interacts with cytochrome c oxidase and mitoBKCa can be modulated by substrates of the respiratory chain. mitoBKCa channel has a central role in protecting the heart from ischemia, where pharmacological activation of the channel impacts the generation of reactive oxygen species and mitochondrial Ca2+ preventing cell death likely by impeding uncontrolled opening of the mitochondrial transition pore. Supporting this view, inhibition of mitoBKCa with Iberiotoxin, enhances cytochrome c release from glioma mitochondria. Many tantalizing questions remain. Some of them are: how is mitoBKCa coupled to the respiratory chain? Does mitoBKCa play non-conduction roles in mitochondria physiology? Which are the functional partners of mitoBKCa? What are the roles of mitoBKCa in other cell types? Answers to these questions are essential to define the impact of mitoBKCa channel in mitochondria biology and disease.

  15. Channels of Propaganda.

    Science.gov (United States)

    Sproule, J. Michael

    Defining propaganda as "efforts by special interests to win over the public covertly by infiltrating messages into various channels of public expression ordinarily viewed as politically neutral," this book argues that propaganda has become pervasive in American life. Pointing out that the 1990s society is inundated with propaganda from…

  16. Chemistry in Microfluidic Channels

    Science.gov (United States)

    Chia, Matthew C.; Sweeney, Christina M.; Odom, Teri W.

    2011-01-01

    General chemistry introduces principles such as acid-base chemistry, mixing, and precipitation that are usually demonstrated in bulk solutions. In this laboratory experiment, we describe how chemical reactions can be performed in a microfluidic channel to show advanced concepts such as laminar fluid flow and controlled precipitation. Three sets of…

  17. First assessment of the ecological status of Karaoun reservoir, Lebanon

    International Nuclear Information System (INIS)

    Fadel, A.; Lemaire, B.; Vinc on Leite, B.; Tassin, B.; Amacha, N.; Slim, K.; Atoui, A.

    2014-01-01

    Many reservoirs have been constructed throughout the world during the 20th century, with many also suffering from eutrophication. The resulting increased phytoplankton biomass in reservoirs impairs their use. Except for Lake Kinneret, the environmental status of lakes and reservoirs in the Middle East is poorly documented. Karaoun reservoir, also known as Qaroun, Qaraoun or Qarun, is the largest water body in Lebanon, having been constructed for irrigation and hydropower production. This present study reviews Karaoun reservoir, including its characteristics, uses, water quality and phytoplankton succession, to assess the environmental status of the reservoir on the basis of the few existing previous publications about the reservoir. Since 2004, which is 39 years after its construction, the reservoir is considered to be hypereutrophic, with low phytoplankton biodiversity and regular blooms of toxic cyanobacteria. The nutrient and trace metal concentrations would not prevent use of the reservoir for a drinking water supply for Beirut, as is currently being planned, although not all the micropollutants in the lake were documented. Karaoun reservoir is compared to other monitored lakes and reservoirs around the Mediterranean Sea. They share annual toxic cyanobacteria blooms of Aphanizomenon ovalisporum and of Microcystis aeruginosa. The phytoplankton composition and succession of Karaoun reservoir is more similar to El Gergal reservoir (Spain) than nearby natural lakes such as Lake Kinneret (Israel) and Lake Trichonis (Greece). Phytoplankton diversity in Karaoun reservoir was the lowest, due to higher nutrient concentrations and a larger decrease in water level in the dry season. Karaoun reservoir represents an interesting example of the potential response of the phytoplankton community in other lakes and reservoirs during the drought periods expected to occur as a result of global climate change. (author)

  18. Channeling through Bent Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Mack, Stephanie; /Ottawa U. /SLAC

    2012-09-07

    Bent crystals have demonstrated potential for use in beam collimation. A process called channeling is when accelerated particle beams are trapped by the nuclear potentials in the atomic planes within a crystal lattice. If the crystal is bent then the particles can follow the bending angle of the crystal. There are several different effects that are observed when particles travel through a bent crystal including dechanneling, volume capture, volume reflection and channeling. With a crystal placed at the edge of a particle beam, part of the fringe of the beam can be deflected away towards a detector or beam dump, thus helping collimate the beam. There is currently FORTRAN code by Igor Yazynin that has been used to model the passage of particles through a bent crystal. Using this code, the effects mentioned were explored for beam energy that would be seen at the Facility for Advanced Accelerator Experimental Tests (FACET) at a range of crystal orientations with respect to the incoming beam. After propagating 5 meters in vacuum space past the crystal the channeled particles were observed to separate from most of the beam with some noise due to dechanneled particles. Progressively smaller bending radii, with corresponding shorter crystal lengths, were compared and it was seen that multiple scattering decreases with the length of the crystal therefore allowing for cleaner detection of the channeled particles. The input beam was then modified and only a portion of the beam sent through the crystal. With the majority of the beam not affected by the crystal, most particles were not deflected and after propagation the channeled particles were seen to be deflected approximately 5mm. After a portion of the beam travels through the crystal, the entire beam was then sent through a quadrupole magnet, which increased the separation of the channeled particles from the remainder of the beam to a distance of around 20mm. A different code, which was developed at SLAC, was used to

  19. Calculation of reservoir capacity loss due to sediment deposition in the `Muela reservoir, Northern Lesotho

    Directory of Open Access Journals (Sweden)

    Liphapang Khaba

    2017-06-01

    Full Text Available Bathymetry survey records of the `Muela Reservoir in northern Lesotho were obtained from the Lesotho Highlands Development Authority (LHDA with the aim of identifying reservoir storage capacity loss due to sediment deposition, between 1985 and 2015. For this purpose, data from eight surveys completed between 1985 and January 2015 were analyzed to quantify bathymetric change between each survey. Four interpolation methods (inverse distance weighting, Kriging, natural neighbor, and spline, were used to create digital terrain models from each survey data-set. In addition, a triangulated irregular network (TIN surface was created from each data-set. The average reservoir storage capacity loss of 15,400 m3/year was determined across the whole period between 1985 and early 2015, based on Kriging. Whilst the results indicate high inter-annual variability in the rate of reservoir capacity reduction, consideration of errors in the surveying and reservoir volumetric calculation methods suggest that rates of reservoir volume reduction can vary between 11,400 m3/year and 18,200 m3/year.

  20. Sudden water pollution accidents and reservoir emergency operations: impact analysis at Danjiangkou Reservoir.

    Science.gov (United States)

    Zheng, Hezhen; Lei, Xiaohui; Shang, Yizi; Duan, Yang; Kong, Lingzhong; Jiang, Yunzhong; Wang, Hao

    2018-03-01

    Danjiangkou Reservoir is the source reservoir of the Middle Route of the South-to-North Water Diversion Project (MRP). Any sudden water pollution accident in the reservoir would threaten the water supply of the MRP. We established a 3-D hydrodynamic and water quality model for the Danjiangkou Reservoir, and proposed scientific suggestions on the prevention and emergency management for sudden water pollution accidents based on simulated results. Simulations were performed on 20 hypothetical pollutant discharge locations and 3 assumed amounts, in order to model the effect of pollutant spreading under different reservoir operation types. The results showed that both the location and mass of pollution affected water quality; however, different reservoir operation types had little effect. Five joint regulation scenarios, which altered the hydrodynamic processes of water conveyance for the Danjiangkou and Taocha dams, were considered for controlling pollution dispersion. The results showed that the spread of a pollutant could be effectively controlled through the joint regulation of the two dams and that the collaborative operation of the Danjiangkou and Taocha dams is critical for ensuring the security of water quality along the MRP.