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Sample records for reservoirs levees channel

  1. Growth, Failure, and Erosion of Submarine Channel Levees on the Upper Mississippi Fan, Gulf of Mexico

    Science.gov (United States)

    Sawyer, D. E.; Flemings, P. B.; Nikolinakou, M. A.

    2011-12-01

    Late Pleistocene channel levees on the Mississippi Fan failed repeatedly along deep-seated listric faults. These growth faults begin at the top of the levee, as much as a kilometer away from the channel axis. They plunge 150-200 meters downward reaching their deepest point halfway towards the channel axis (0.5 km) along the base of a regional sand unit. They then rise toward the channel axis where they emerge. The erosion of toe-thrust material coupled with levee growth, promoted a dynamic equilibrium: turbidity currents flushed the channel axis and deposited new levee on the margins, which induced further displacement into the channel. With a geomechanical model we show that deep-seated failure occurred by undrained loading of an underlying low permeability mudstone. Excess pore pressure formed a low-strength layer that localized the detachment at the base of a regional sand. Our results show that deep-seated failure is expected when levee systems form above regional sand bodies that were deposited rapidly above low permeability mudstone. Furthermore, the presence of this failure style in channel-levee systems is a strong indicator that overpressures and low effective stresses were present during formation and thus record paleo-pressures. Understanding these systems is critical for the design of safe well penetrations, predicting hydraulic connectivity of deepwater channel sands, and the growth of submarine channel-levee systems. This study illuminates the linkages between sedimentation, erosion, and the mechanical stability of levees in submarine channel systems.

  2. Technical Note: Stability of a Levee Made of Bottom Sediments From a Dam Reservoir

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    Koś Karolina

    2015-02-01

    Full Text Available Stability analysis of a levee made of the bottom sediments from Czorsztyn-Niedzica Reservoir is presented in the paper. These sediments were classified as silty sands and, based on the authors' own research, their geotechnical parameters were beneficial, so the possibility of using this material for the hydraulic embankments was considered. Stability and filtration calculations were carried out for a levee that had the same top width - 3 m, slope inclinations 1:2 and different heights: 4, 6 and 8 m. Two methods were used: analytical and numerical. Calculations were carried out without and with a steady and unsteady seepage filtration. Based on the analysis carried out it was stated that the levee made of the bottom sediments is stable even at the height of 8.0 m, although because of the seepage on the downstream side it is recommended to use a drainage at the toe of the slope.

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

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    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

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

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    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

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

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    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 (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-carbonate deep-water basins.

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

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    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

  7. Stratigraphic Stacking of Deepmarine Channel Levee Turbidites: Scales of Cyclicity and their Origin. Examples from the Laingsburg Fm. (Karoo, South Africa) and the Rosario Fm. (Baja, Mexico)

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    Kane, I. A.; Hodgson, D.

    2009-12-01

    Thinning upwards of the turbidite beds that form deepmarine channel levees is a common motif reported from modern and recent levees on the seafloor, from subsurface examples, and from outcropping ancient examples. Because levees are thought to be built by deposition from turbidity currents superelevated over their channel form, the volume and style of overbank deposition are controlled primarily by the relationship between levee height (i.e., thalweg to crest) and flow thickness, determining the amount of overspill. Thus stratigraphic variability of turbidite thickness is explained by some change in either or both of those factors, which may arise autocyclicly or allocyclicly. Variation in the ratio of intra-channel and extra-channel deposition can be an autocyclic stratigraphic response, e.g., in bypass dominated systems, thalweg aggradation may be retarded with respect to levee aggradation, hence as levee relief increases, flows become more confined and, given a relatively narrow range of flow sizes, the volume of overbank flow and deposit thickness decrease with stratigraphic height. However, the same stratigraphic response of the levee may occur due to allocyclic flow magnitude variation, i.e., through decreasing flow magnitude. In both the autocyclic and allocyclic case the stratigraphic response of the levee may be one of thinning upwards, even if the overall system response may be one of progradation (autocyclic bypassing case) or retrogradation (allocyclic decreasing flow magnitude case), with entirely different connotations for sequence stratigraphic interpretation. Here we report examples of different scales of bed thickness cyclicity (both thickening and thinning upward cycles superimposed by smaller scale cycles) within levees of the Rosario Formation, Baja California, Mexico, and from the Laingsburg Formation, Karoo, South Africa, and, together with published examples, discuss criteria for the recognition, and drivers of, autocyclic and allocyclic bed

  8. Reservoir architecture patterns of sandy gravel braided distributary channel

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    Senlin Yin

    2016-06-01

    Full Text Available The purpose of this study was to discuss shape, scale and superimposed types of sandy gravel bodies in sandy-gravel braided distributary channel. Lithofacies analysis, hierarchy bounding surface analysis and subsurface dense well pattern combining with outcrops method were used to examine reservoir architecture patterns of sandy gravel braided distributary channel based on cores, well logging, and outcrops data, and the reservoir architecture patterns of sandy gravel braided distributary channels in different grades have been established. The study shows: (1 The main reservoir architecture elements for sandy gravel braided channel delta are distributary channel and overbank sand, while reservoir flow barrier elements are interchannel and lacustrine mudstone. (2 The compound sand bodies in the sandy gravel braided delta distributary channel take on three shapes: sheet-like distributary channel sand body, interweave strip distributary channel sand body, single strip distributary channel sand body. (3 Identification marks of single distributary channel include: elevation of sand body top, lateral overlaying, “thick-thin-thick” feature of sand bodies, interchannel mudstone and overbank sand between distributary channels and the differences in well log curve shape of sand bodies. (4 Nine lithofacies types were distinguished in distributary channel unit interior, different channel units have different lithofacies association sequence.

  9. Morphological Analyses and Simulated Flood Elevations in a Watershed with Dredged and Leveed Stream Channels, Wheeling Creek, Eastern Ohio

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    Sherwood, James M.; Huitger, Carrie A.; Ebner, Andrew D.; Koltun, G.F.

    2008-01-01

    The USGS, in cooperation with the Ohio Emergency Management Agency, conducted a study in the Wheeling Creek Basin to (1) evaluate and contrast land-cover characteristics from 2001 with characteristics from 1979 and 1992; (2) compare current streambed elevation, slope, and geometry with conditions present in the late 1980s; (3) look for evidence of channel filling and over widening in selected undredged reaches; (4) estimate flood elevations for existing conditions in both undredged and previously dredged reaches; (5) evaluate the height of the levees required to contain floods with selected recurrence intervals in previously dredged reaches; and (6) estimate flood elevations for several hypothetical dredging and streambed aggradation scenarios in undredged reaches. The amount of barren land in the Wheeling Creek watershed has decreased from 20 to 1 percent of the basin area based on land-cover characteristics from 1979 and 2001. Barren lands appear to have been converted primarily to pasture, presumably as a result of surface-mine reclamation. Croplands also decreased from 13 to 8 percent of the basin area. The combined decrease in barren lands and croplands is approximately offset by the increase in pasture. Stream-channel surveys conducted in 1987 and again in 2006 at 21 sites in four previously dredged reaches of Wheeling Creek indicate little change in the elevation, slope, and geometry of the channel at most sites. The mean change in width-averaged bed and thalweg elevations for the 21 cross sections was 0.1 feet. Bankfull widths, mean depths, and cross-sectional areas measured at 12 sites in undredged reaches were compared to estimates determined from regional equations. The mean percentage difference between measured and estimated bankfull widths was -0.2 percent, suggesting that bankfull widths in the Wheeling Creek Basin are generally about the same as regional averages for undisturbed basins of identical drainage area. For bankfull mean depth and cross

  10. 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

  11. Erosion of Earthen Levees by Wave Action

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    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.

  12. Hydrodynamic and sedimentological controls governing formation of fluvial levees

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    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.

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

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

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    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.

  15. Environmental Statement for Lavon Dam and Reservoir Modification and East Fork Channel Improvement - Pertaining to East Fork Channel and Levee Improvement Increment I. Supplement.

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    1977-01-01

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

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    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

  17. Capacity of the inflow river channels of the Krpelany and Hricov reservoirs with respect to flood control

    International Nuclear Information System (INIS)

    Capekova, Z.

    2004-01-01

    In this presentation author deals with the capacity of the inflow river channels of the Krpelany and Hricov reservoirs with respect to flood control (Vah River, Orava River, Kysuce River and Rajcianka River, Slovakia)

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

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    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

  19. Dams and Levees: Safety Risks

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    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

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

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    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

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

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    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.

  2. Protection of Levees against Beavers

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    Kozłowski, Wojciech; Balawejder, Adam

    2017-10-01

    Beavers are a protected species, so the levees must be properly protected so as not to harm the beavers and protect the levees from the destruction caused by these animals. This protection requires the use of bentonite mats as shaft seals, and wire mesh. Recently, such new protection structures began to be used successfully.

  3. 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

  4. 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...

  5. Levee Lines - 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...

  6. 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

  7. Improving recovery efficiency of water-drive channel sandstone reservoir by drilling wells laterally

    Energy Technology Data Exchange (ETDEWEB)

    Zhiguo, F.; Quinglong, D.; Pingshi, Z.; Bingyu, J.; Weigang, L. [Research Institute of Exploration and Development, Daqing (China)

    1998-12-31

    Example of drilling a horizontal well in reservoir rock of only four meter thick by using existing casing pipe of low efficiency vertical wells to induce production in the top remaining reservoir is described. The experience shows that drilling horizontal wells laterally in thin bodies of sandstone reservoirs and improve their productivity is a feasible proposition. Productivity will still be low, but it can be improved by well stimulation. 3 refs., 3 figs.

  8. A Bivariate return period for levee failure monitoring

    Science.gov (United States)

    Isola, M.; Caporali, E.

    2017-12-01

    Levee breaches are strongly linked with the interaction processes among water, soil and structure, thus many are the factors that affect the breach development. One of the main is the hydraulic load, characterized by intensity and duration, i.e. by the flood event hydrograph. On the magnitude of the hydraulic load is based the levee design, generally without considering the fatigue failure due to the load duration. Moreover, many are the cases in which the levee breach are characterized by flood of magnitude lower than the design one. In order to implement the strategies of flood risk management, we built here a procedure based on a multivariate statistical analysis of flood peak and volume together with the analysis of the past levee failure events. Particularly, in order to define the probability of occurrence of the hydraulic load on a levee, a bivariate copula model is used to obtain the bivariate joint distribution of flood peak and volume. Flood peak is the expression of the load magnitude, while the volume is the expression of the stress over time. We consider the annual flood peak and the relative volume. The volume is given by the hydrograph area between the beginning and the end of event. The beginning of the event is identified as an abrupt rise of the discharge by more than 20%. The end is identified as the point from which the receding limb is characterized by the baseflow, using a nonlinear reservoir algorithm as baseflow separation technique. By this, with the aim to define warning thresholds we consider the past levee failure events and the relative bivariate return period (BTr) compared with the estimation of a traditional univariate model. The discharge data of 30 hydrometric stations of Arno River in Tuscany, Italy, in the period 1995-2016 are analysed. The database of levee failure events, considering for each event the location as well as the failure mode, is also created. The events were registered in the period 2000-2014 by EEA

  9. 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.

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

    KAUST Repository

    Sana, Furrukh; Ravanelli, Fabio; Al-Naffouri, Tareq Y.; Hoteit, Ibrahim

    2016-01-01

    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.

  11. Suspended-sediment loads, reservoir sediment trap efficiency, and upstream and downstream channel stability for Kanopolis and Tuttle Creek Lakes, Kansas, 2008-10

    Science.gov (United States)

    Juracek, Kyle E.

    2011-01-01

    Continuous streamflow and turbidity data collected from October 1, 2008, to September 30, 2010, at streamgage sites upstream and downstream from Kanopolis and Tuttle Creek Lakes, Kansas, were used to compute the total suspended-sediment load delivered to and released from each reservoir as well as the sediment trap efficiency for each reservoir. Ongoing sedimentation is decreasing the ability of the reservoirs to serve several purposes including flood control, water supply, and recreation. River channel stability upstream and downstream from the reservoirs was assessed using historical streamgage information. For Kanopolis Lake, the total 2-year inflow suspended-sediment load was computed to be 600 million pounds. Most of the suspended-sediment load was delivered during short-term, high-discharge periods. The total 2-year outflow suspended-sediment load was computed to be 31 million pounds. Sediment trap efficiency for the reservoir was estimated to be 95 percent. The mean annual suspended-sediment yield from the upstream basin was estimated to be 129,000 pounds per square mile per year. No pronounced changes in channel width were evident at five streamgage sites located upstream from the reservoir. At the Ellsworth streamgage site, located upstream from the reservoir, long-term channel-bed aggradation was followed by a period of stability. Current (2010) conditions at five streamgages located upstream from the reservoir were typified by channel-bed stability. At the Langley streamgage site, located immediately downstream from the reservoir, the channel bed degraded 6.15 feet from 1948 to 2010. For Tuttle Creek Lake, the total 2-year inflow suspended-sediment load was computed to be 13.3 billion pounds. Most of the suspended-sediment load was delivered during short-term, high-discharge periods. The total 2-year outflow suspended-sediment load was computed to be 327 million pounds. Sediment trap efficiency for the reservoir was estimated to be 98 percent. The mean

  12. 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

  13. 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

  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. Levee Health Monitoring With Radar Remote Sensing

    Science.gov (United States)

    Jones, C. E.; Bawden, G. W.; Deverel, S. J.; Dudas, J.; Hensley, S.; Yun, S.

    2012-12-01

    Remote sensing offers the potential to augment current levee monitoring programs by providing rapid and consistent data collection over large areas irrespective of the ground accessibility of the sites of interest, at repeat intervals that are difficult or costly to maintain with ground-based surveys, and in rapid response to emergency situations. While synthetic aperture radar (SAR) has long been used for subsidence measurements over large areas, applying this technique directly to regional levee monitoring is a new endeavor, mainly because it requires both a wide imaging swath and fine spatial resolution to resolve individual levees within the scene, a combination that has not historically been available. Application of SAR remote sensing directly to levee monitoring has only been attempted in a few pilot studies. Here we describe how SAR remote sensing can be used to assess levee conditions, such as seepage, drawing from the results of two levee studies: one of the Sacramento-San Joaquin Delta levees in California that has been ongoing since July 2009 and a second that covered the levees near Vicksburg, Mississippi, during the spring 2011 floods. These studies have both used data acquired with NASA's UAVSAR L-band synthetic aperture radar, which has the spatial resolution needed for this application (1.7 m single-look), sufficiently wide imaging swath (22 km), and the longer wavelength (L-band, 0.238 m) required to maintain phase coherence between repeat collections over levees, an essential requirement for applying differential interferometry (DInSAR) to a time series of repeated collections for levee deformation measurement. We report the development and demonstration of new techniques that employ SAR polarimetry and differential interferometry to successfully assess levee health through the quantitative measurement of deformation on and near levees and through detection of areas experiencing seepage. The Sacramento-San Joaquin Delta levee study, which covers

  17. 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

  18. Effect of bait and gear type on channel catfish catch and turtle bycatch in a reservoir

    Science.gov (United States)

    Cartabiano, Evan C.; Stewart, David R.; Long, James M.

    2014-01-01

    Hoop nets have become the preferred gear choice to sample channel catfish Ictalurus punctatus but the degree of bycatch can be high, especially due to the incidental capture of aquatic turtles. While exclusion and escapement devices have been developed and evaluated, few have examined bait choice as a method to reduce turtle bycatch. The use of Zote™ soap has shown considerable promise to reduce bycatch of aquatic turtles when used with trotlines but its effectiveness in hoop nets has not been evaluated. We sought to determine the effectiveness of hoop nets baited with cheese bait or Zote™ soap and trotlines baited with shad or Zote™ soap as a way to sample channel catfish and prevent capture of aquatic turtles. We used a repeated-measures experimental design and treatment combinations were randomly assigned using a Latin-square arrangement. Eight sampling locations were systematically selected and then sampled with either hoop nets or trotlines using Zote™ soap (both gears), waste cheese (hoop nets), or cut shad (trotlines). Catch rates did not statistically differ among the gear–bait-type combinations. Size bias was evident with trotlines consistently capturing larger sized channel catfish compared to hoop nets. Results from a Monte Carlo bootstrapping procedure estimated the number of samples needed to reach predetermined levels of sampling precision to be lowest for trotlines baited with soap. Moreover, trotlines baited with soap caught no aquatic turtles, while hoop nets captured many turtles and had high mortality rates. We suggest that Zote™ soap used in combination with multiple hook sizes on trotlines may be a viable alternative to sample channel catfish and reduce bycatch of aquatic turtles.

  19. 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

  20. 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.

  1. Environment - Borrow Area for Temporary Levee

    Data.gov (United States)

    Army Corps of Engineers, Department of the Army, Department of Defense — This data represents the location of a borrow site for construction materials used in temporary levee building during flood events. The footprint of these areas have...

  2. Rates of consumption of juvenile salmonids and alternative prey fish by northern squawfish, walleyes, smallmouth bass, and channel catfish in John Day Reservoir, Columbia River

    International Nuclear Information System (INIS)

    Vigg, S.; Poe, T.P.; Prendergast, L.A.; Hansel, H.C.

    1991-01-01

    Adult northern squawfish Ptychocheilus oregonesis, walleyes Stizostedion vitreum, smallmouth bass Micropterus dolomieu, and channel catfish Ictalurus punctatus were sampled from four regions of John Day Reservoir from April to August 1983-1986 to quantify their consumption of 13 species of prey fish, particularly seaward-migrating juvenile Pacific salmon and steelhead (Oncorhynchus spp.). Consumption rates were estimated from field data on stomach contents and digestion rate relations determined in previous investigations. For each predator, consumption rates varied by reservoir area, month, time of day, and predator size or age. The greatest daily consumption of salmonids by northern squawfish and channel catfish occurred in the upper end of the reservoir below McNary Dam. Greatest daily predation by walleyes and smallmouth bass occurred in the middle and lower reservoir. Consumption rates of all predators were highest in July, concurrent with maximum temperature and abundance of juvenile salmonids. Feeding by the predators tended to peak after dawn and near midnight. Northern squawfish below McNary Dam exhibited this pattern, but fed mainly in the morning hours down-reservoir. The daily ration of total prey fish was highest for northern squawfish over 451 mm fork length, for walleyes 201-250 mm, for smallmouth bass 176-200 mm, and for channel catfish 401-450 mm. Averaged over all predator sizes and sampling months (April-August), the total daily ration (fish plus other prey) of smallmouth bass was about twice that of channel catfish, northern squawfish, and walleyes. However, northern squawfish was clearly the major predator on juvenile salmonids

  3. Applying Mechanistic Dam Breach Models to Historic Levee Breaches

    OpenAIRE

    Risher Paul; Gibson Stanford

    2016-01-01

    Hurricane Katrina elevated levee risk in the US national consciousness, motivating agencies to assess and improve their levee risk assessment methodology. Accurate computation of the flood flow magnitude and timing associated with a levee breach remains one of the most difficult and uncertain components of levee risk analysis. Contemporary methods are largely empirical and approximate, introducing substantial uncertainty to the damage and life loss models. Levee breach progressions are often ...

  4. Phytoplankton community: indicator of water quality in the Armando Ribeiro Gonçalves Reservoir and Pataxó Channel, Rio Grande do Norte, Brazil

    Directory of Open Access Journals (Sweden)

    NT. Chellappa

    Full Text Available The current study analysed spatial-temporal modifications of the phytoplankton community and water quality, during dry and wet seasons. The phytoplankton community was studied in three areas: Armando Ribeiro Gonçalves Reservoir (ARG, which is an important public use reservoir in RN, Pataxó Channel (PC-before water treatment, Itajá, RN, and after the water treatment (WTP. Water samples from the reservoir were collected during both dry (January, February and November, 2006 and wet seasons (March to June, 2006. Quali-quantitative analyses of phytoplankton were carried out. Results indicated a qualitative similarity of the phytoplankton community in the three areas. However, significant differences were registered in these areas in relation to species relative abundance, with dominance of potentially toxic cyanobacteria, such as Planktothrix agardhii Gomont (dry season and Microcystis aeruginosa Kutz (wet season. Ecological indexes obtained higher values before water treatment. Nevertheless, densities of cyanobacteria (organisms/mL gradually reduced in the waters of the reservoir and of the Pataxó Channel before and after water treatment. After the treatment, density values of cyanobacteria were adequate for human consumption, according to the values established by the Health Ministry.

  5. 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.

  6. 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.

  7. Linking submarine channel–levee facies and architecture to flow structure of turbidity currents: : insights from flume tank experiments

    NARCIS (Netherlands)

    de Leeuw, J.|info:eu-repo/dai/nl/380590913; Eggenhuisen, J.T.|info:eu-repo/dai/nl/322850274; Cartigny, M.J.B.|info:eu-repo/dai/nl/304823716

    Submarine leveed channels are sculpted by turbidity currents that are commonly highly stratified. Both the concentration and the grain size decrease upward in the flow, and this is a fundamental factor that affects the location and grain size of deposits around a channel. This study presents

  8. River Loire levees hazard studies – CARDigues’ model principles and utilization examples on Blois levees

    Directory of Open Access Journals (Sweden)

    Durand Eduard

    2016-01-01

    Full Text Available Along the river Loire, in order to have a homogenous method to do specific risk assessment studies, a new model named CARDigues (for Levee Breach Hazard Calculation was developed in a partnership with DREAL Centre-Val de Loire (owner of levees, Cerema and Irstea. This model enables to approach the probability of failure on every levee sections and to integrate and cross different “stability” parameters such topography and included structures, geology and material geotechnical characteristics, hydraulic loads… and observations of visual inspections or instrumentation results considered as disorders (seepage, burrowing animals, vegetation, pipes, etc.. This model and integrated tool CARDigues enables to check for each levee section, the probability of appearance and rupture of five breaching scenarios initiated by: overflowing, internal erosion, slope instability, external erosion and uplift. It has been recently updated and has been applied on several levee systems by different contractors. The article presents the CARDigues model principles and its recent developments (version V28.00 with examples on river Loire and how it is currently used for a relevant and global levee system diagnosis and assessment. Levee reinforcement or improvement management is also a perspective of applications for this model CARDigues.

  9. Assessing the role of large wood entrained in the 2013 Colorado Front Range flood in ongoing channel response and reservoir management

    Science.gov (United States)

    Bennett, Georgina; Rathburn, Sara; Ryan, Sandra; Wohl, Ellen; Blair, Aaron

    2016-04-01

    Considerable quantities of large wood (LW) may be entrained during floods with long lasting impacts on channel morphology, sediment and LW export, and downstream reservoir management. Here we present an analysis of LW entrained by an extensive flood in Colorado, USA. Over a 5 day period commencing 9th September 2013, up to 450 mm of rain, or ~1000% of the monthly average, fell in catchments spanning a 100-km-wide swath of the Colorado Front Range resulting in major flooding. Catchment response was dramatic, with reports of 100s - 1000s of years of erosion, destruction of infrastructure and homes, and sediment and LW loading within reservoirs. One heavily impacted catchment is the North St Vrain, draining 250km2 of the South Platte drainage basin. In addition to widespread channel enlargement, remote imagery reveals hundreds of landslides that delivered sediment and LW to the channel and ultimately to Ralph Price Reservoir, which provides municipal water to Longmont. The City of Longmont facilitated the removal of ~1050 m3 of wood deposited at the reservoir inlet by the flood but the potential for continued movement of large wood in the catchment presents an on-going concern for reservoir management. In collaboration with the City of Longmont, our objectives are (1) to quantify the volume of wood entrained by the flood and still stored along the channel, (2) characterize the size and distribution of LW deposits and (3) determine their role in ongoing catchment flood response and recovery. We utilize freely available pre and post flood NAIP 4-band imagery to calculate a normalized differential vegetation index (NDVI) difference map with which we calculate the area of vegetation entrained by the flood. We combine this with field assessments and a map of vegetation type automatically classified from optical satellite imagery to estimate the total flood-entrained volume of wood. Preliminary testing of 'stream selfies' - structure from motion imaging of LW deposits using

  10. Overview of Levee Setback Projects and Benefits

    Science.gov (United States)

    2017-07-31

    other life-history stages of fish and other aquatic organisms . Levees can also increase the frequency of common floods in the floodplain where they...projects is the use of flood- borne sediments to supplement fertilizers in flooded farm fields. Historically, floodwaters were a significant source of

  11. Numerical Hydrodynamic Study of Hypothetical Levee Setback Scenarios

    Science.gov (United States)

    2018-01-01

    has recorded peak flows up to 9,919 cms (350,000 cfs) before the construction of flow control dams. The New Savannah Bluff Lock and Dam (NSBLD...of the levee setback alternatives at the observation point downstream of the levee setbacks are nearly identical as the WSE of the base condition...the levee setback, respectively. The WSE of the levee setback alternatives at the observation point downstream are nearly identical as the WSE of the

  12. 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)

  13. Assessing the impacts of dams and levees on the hydrologic record of the Middle and Lower Mississippi River, USA

    Science.gov (United States)

    Remo, Jonathan W.F.; Ickes, Brian; Ryherd, Julia K.; Guida, Ross J.; Therrell, Matthew D.

    2018-01-01

    The impacts of dams and levees on the long-term (>130 years) discharge record was assessed along a ~1200 km segment of the Mississippi River between St. Louis, Missouri, and Vicksburg, Mississippi. To aid in our evaluation of dam impacts, we used data from the U.S. National Inventory of Dams to calculate the rate of reservoir expansion at five long-term hydrologic monitoring stations along the study segment. We divided the hydrologic record at each station into three periods: (1) a pre-rapid reservoir expansion period; (2) a rapid reservoir expansion period; and (3) a post-rapid reservoir expansion period. We then used three approaches to assess changes in the hydrologic record at each station. Indicators of hydrologic alteration (IHA) and flow duration hydrographs were used to quantify changes in flow conditions between the pre- and post-rapid reservoir expansion periods. Auto-regressive interrupted time series analysis (ARITS) was used to assess trends in maximum annual discharge, mean annual discharge, minimum annual discharge, and standard deviation of daily discharges within a given water year. A one-dimensional HEC-RAS hydraulic model was used to assess the impact of levees on flood flows. Our results revealed that minimum annual discharges and low-flow IHA parameters showed the most significant changes. Additionally, increasing trends in minimum annual discharge during the rapid reservoir expansion period were found at three out of the five hydrologic monitoring stations. These IHA and ARITS results support previous findings consistent with the observation that reservoirs generally have the greatest impacts on low-flow conditions. River segment scale hydraulic modeling revealed levees can modestly increase peak flood discharges, while basin-scale hydrologic modeling assessments by the U.S. Army Corps of Engineers showed that tributary reservoirs reduced peak discharges by a similar magnitude (2 to 30%). This finding suggests that the effects of dams and

  14. 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

  15. Climate and floods still govern California levee breaks

    Science.gov (United States)

    Florsheim, J.L.; Dettinger, M.D.

    2007-01-01

    Even in heavily engineered river systems, climate still governs flood variability and thus still drives many levee breaks and geomorphic changes. We assemble a 155-year record of levee breaks for a major California river system to find that breaks occurred in 25% of years during the 20th Century. A relation between levee breaks and river discharge is present that sets a discharge threshold above which most levee breaks occurred. That threshold corresponds to small floods with recurrence intervals of ???2-3 years. Statistical analysis illustrates that levee breaks and peak discharges cycle (broadly) on a 12-15 year time scale, in time with warm-wet storm patterns in California, but more slowly or more quickly than ENSO and PDO climate phenomena, respectively. Notably, these variations and thresholds persist through the 20th Century, suggesting that historical flood-control effects have not reduced the occurrence or frequency of levee breaks. Copyright 2007 by the American Geophysical Union.

  16. Hvordan er det å leve med CRPS?

    OpenAIRE

    Hovind, Thomas

    2014-01-01

    Hensikten med denne studien er å se på hvordan pasienter med komplekst regionalt smertesyndrom (CRPS) opplever å leve med tilstanden og hvordan disse pasientene har opplevd å bli møtt i helsevesenet. CRPS er en langvarig tilstand med sterke smerter som kan medføre økt smerterespons, redusert funksjon og nedsatt livskvalitet hos pasientene. Studien er en kvalitativ undersøkelse basert på dybdeintervju av fire pasienter med CRPS. Pasientene ble rekruttert fra en smerteavdeling i Nord-Norge og u...

  17. Improving Oil Recovery (IOR) with Polymer Flooding in a Heavy-Oil River-Channel Sandstone Reservoir

    OpenAIRE

    Lu, Hongjiang

    2009-01-01

    Most of the old oil fields in China have reached high water cut stage, in order to meet the booming energy demanding, oil production rate must be kept in the near future with corresponding IOR (Improving Oil Recovery) methods. Z106 oilfield lies in Shengli Oilfields Area at the Yellow River delta. It was put into development in 1988. Since the oil belongs to heavy oil, the oil-water mobility ratio is so unfavourable that water cut increases very quickly. Especially for reservoir Ng21, the san...

  18. Crevasse Splays Versus Avulsions: A Recipe for Land Building With Levee Breaches

    Science.gov (United States)

    Nienhuis, Jaap H.; Törnqvist, Torbjörn E.; Esposito, Christopher R.

    2018-05-01

    Natural-levee breaches can not only initiate an avulsion but also, under the right circumstances, lead to crevasse splay formation and overbank sedimentation. The formative conditions for crevasse splays are not well understood, yet such river sediment diversions form an integral part of billion-dollar coastal restoration projects. Here we use Delft3D to investigate the influence of vegetation and soil consolidation on the evolution of a natural-levee breach. Model simulations show that crevasse splays heal because floodplain aggradation reduces the water surface slope, decreasing water discharge into the flood basin. Easily erodible and unvegetated floodplains increase the likelihood for channel avulsions. Denser vegetation and less potential for soil consolidation result in small crevasse splays that are not only efficient sediment traps but also short-lived. Successful crevasse splays that generate the largest land area gain for the imported sediment require a delicate balance between water and sediment discharge, vegetation root strength, and soil consolidation.

  19. McGee Creek Drainage and Levee District, Illinois.

    Science.gov (United States)

    1973-04-01

    J COUNTY MC GEE REEK DRAINAGE BLEVEE DISTRICT N~ i, 0. ~ I I LEGEND Co ,. 3 ~ . -~------~----EXISTING LEVEE _____________PROPOSED LEVEE...Development, Conservation, Environmental Protection Agency, Health, Institute for Environmental Quality, Mines and Minerals. Pollution Control Board...Protection Agency, Health, Institute for Environmental Quality, Mines and Minerals, Pollution Control Board, Registration and Education, Transportation

  20. Efeitos do treinamento auditivo em idosos com Comprometimento Cognitivo Leve

    OpenAIRE

    Renata Rezende de Almeida Ávila; Cristina Ferraz Borges Murphy; Eliane Schochat

    2014-01-01

    INTRODUÇÃO: Pesquisas demonstram a existência do Transtorno do Processamento Auditivo em indivíduos com Comprometimento Cognitivo Leve. OBJETIVO: Verificar os efeitos de um treinamento auditivo, em indivíduos com comprometimento cognitivo leve. MÉTODOS: Participaram 25 indivíduos, com idades entre 69 e 91 anos e diagnóstico de Comprometimento Cognitivo Leve, sendo que, 10 receberam treinamento auditivo (grupo estudo), 10 receberam treinamento visual (grupo alternativo) e cinco não re...

  1. 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.

  2. Seismic patterns and migration history of submarine fan channels in deep-water area, Niger Delta, West Africa

    Science.gov (United States)

    Zhang, Guotao; Zhang, Shangfeng; Li, Yuan

    2015-04-01

    The channels of deep-water submarine fan under Niger delta slope are characterized by large dimensions special deposition positions and complex formation processes, its geographical location and sedimentary environment also hinder the research and exploration development. According to the strata slicing, RMS amplitude attribute and other techniques, we exhibit the platforms patterns of channels at different period, and based on the analysis of internal architecture and deformation history of channel-leveed systems, migration and evolution process of channel systems could be understood accurately. A great quantity of isolated channels develop in middle Miocene and aggrading streams in late Miocene, which generating because of large scale of turbidity caused by the drop of second order sea-level, which characterized by vertical accretion at smooth channel, while vertical accretion and lateral migration at bend. Evolution of channel systems can be divided into three stages: the initial erosion, erosion and filling alternately, and abandoned stage. With these three stages, the sinuosity of channel change from moderate to high, then decrease. Incision and filling of channels, being during the three development phases, is the driving force of meander-loops migration, which promote three kinds of migration patterns: lateral, down-system and combination migration. The research provides theoretical basis for high-precision prediction and evaluation of deep-water reservoir.

  3. Evaluation of levee setbacks for flood-loss reduction, Middle Mississippi River, USA

    Science.gov (United States)

    Dierauer, Jennifer; Pinter, Nicholas; Remo, Jonathan W. F.

    2012-07-01

    SummaryOne-dimensional hydraulic modeling and flood-loss modeling were used to test the effectiveness of levee setbacks for flood-loss reduction along the Middle Mississippi River (MMR). Four levee scenarios were assessed: (1) the present-day levee configuration, (2) a 1000 m levee setback, (3) a 1500 m levee setback, and (4) an optimized setback configuration. Flood losses were estimated using FEMA's Hazus-MH (Hazards US Multi-Hazard) loss-estimation software on a structure-by-structure basis for a range of floods from the 2- to the 500-year events. These flood-loss estimates were combined with a levee-reliability model to calculate probability-weighted damage estimates. In the simplest case, the levee setback scenarios tested here reduced flood losses compared to current conditions for large, infrequent flooding events but increased flood losses for smaller, more frequent flood events. These increases occurred because levee protection was removed for some of the existing structures. When combined with buyouts of unprotected structures, levee setbacks reduced flood losses for all recurrence intervals. The "optimized" levee setback scenario, involving a levee configuration manually planned to protect existing high-value infrastructure, reduced damages with or without buyouts. This research shows that levee setbacks in combination with buyouts are an economically viable approach for flood-risk reduction along the study reach and likely elsewhere where levees are widely employed for flood control. Designing a levee setback around existing high-value infrastructure can maximize the benefit of the setback while simultaneously minimizing the costs. The optimized levee setback scenario analyzed here produced payback periods (costs divided by benefits) of less than 12 years. With many aging levees failing current inspections across the US, and flood losses spiraling up over time, levee setbacks are a viable solution for reducing flood exposure and flood levels.

  4. Case Study: Zutphen : Estimates of levee system reliability

    NARCIS (Netherlands)

    Roscoe, K.; Kothuis, Baukje; Kok, Matthijs

    2017-01-01

    Estimates of levee system reliability can conflict with experience and intuition. For example, a very high failure probability may be computed while no evidence of failure has been observed, or a very low failure probability when signs of failure have been detected.

  5. 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)

  6. Game theory and risk-based leveed river system planning with noncooperation

    Science.gov (United States)

    Hui, Rui; Lund, Jay R.; Madani, Kaveh

    2016-01-01

    Optimal risk-based levee designs are usually developed for economic efficiency. However, in river systems with multiple levees, the planning and maintenance of different levees are controlled by different agencies or groups. For example, along many rivers, levees on opposite riverbanks constitute a simple leveed river system with each levee designed and controlled separately. Collaborative planning of the two levees can be economically optimal for the whole system. Independent and self-interested landholders on opposite riversides often are willing to separately determine their individual optimal levee plans, resulting in a less efficient leveed river system from an overall society-wide perspective (the tragedy of commons). We apply game theory to simple leveed river system planning where landholders on each riverside independently determine their optimal risk-based levee plans. Outcomes from noncooperative games are analyzed and compared with the overall economically optimal outcome, which minimizes net flood cost system-wide. The system-wide economically optimal solution generally transfers residual flood risk to the lower-valued side of the river, but is often impractical without compensating for flood risk transfer to improve outcomes for all individuals involved. Such compensation can be determined and implemented with landholders' agreements on collaboration to develop an economically optimal plan. By examining iterative multiple-shot noncooperative games with reversible and irreversible decisions, the costs of myopia for the future in making levee planning decisions show the significance of considering the externalities and evolution path of dynamic water resource problems to improve decision-making.

  7. Architecture and reservoir quality of low-permeable Eocene lacustrine turbidite sandstone from the Dongying Depression, East China

    Science.gov (United States)

    Munawar, Muhammad Jawad; Lin, Chengyan; Chunmei, Dong; Zhang, Xianguo; Zhao, Haiyan; Xiao, Shuming; Azeem, Tahir; Zahid, Muhammad Aleem; Ma, Cunfei

    2018-05-01

    The architecture and quality of lacustrine turbidites that act as petroleum reservoirs are less well documented. Reservoir architecture and multiscale heterogeneity in turbidites represent serious challenges to production performance. Additionally, establishing a hierarchy profile to delineate heterogeneity is a challenging task in lacustrine turbidite deposits. Here, we report on the turbidites in the middle third member of the Eocene Shahejie Formation (Es3), which was deposited during extensive Middle to Late Eocene rifting in the Dongying Depression. Seismic records, wireline log responses, and core observations were integrated to describe the reservoir heterogeneity by delineating the architectural elements, sequence stratigraphic framework and lithofacies assemblage. A petrographic approach was adopted to constrain microscopic heterogeneity using an optical microscope, routine core analyses and X-ray diffraction (XRD) analyses. The Es3m member is interpreted as a sequence set composed of four composite sequences: CS1, CS2, CS3 and CS4. A total of forty-five sequences were identified within these four composite sequences. Sand bodies were mainly deposited as channels, levees, overbank splays, lobes and lobe fringes. The combination of fining-upward and coarsening-upward lithofacies patterns in the architectural elements produces highly complex composite flow units. Microscopic heterogeneity is produced by diagenetic alteration processes (i.e., feldspar dissolution, authigenic clay formation and quartz cementation). The widespread kaolinization of feldspar and mobilization of materials enhanced the quality of the reservoir by producing secondary enlarged pores. In contrast, the formation of pore-filling authigenic illite and illite/smectite clays reduced its permeability. Recovery rates are higher in the axial areas and smaller in the marginal areas of architectural elements. This study represents a significant insight into the reservoir architecture and

  8. 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 neural 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

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. Efeitos do treinamento auditivo em idosos com Comprometimento Cognitivo Leve

    Directory of Open Access Journals (Sweden)

    Renata Rezende de Almeida Ávila

    2014-01-01

    Full Text Available INTRODUÇÃO: Pesquisas demonstram a existência do Transtorno do Processamento Auditivo em indivíduos com Comprometimento Cognitivo Leve. OBJETIVO: Verificar os efeitos de um treinamento auditivo, em indivíduos com comprometimento cognitivo leve. MÉTODOS: Participaram 25 indivíduos, com idades entre 69 e 91 anos e diagnóstico de Comprometimento Cognitivo Leve, sendo que, 10 receberam treinamento auditivo (grupo estudo, 10 receberam treinamento visual (grupo alternativo e cinco não receberam intervenção (grupo controle. Testes cognitivos e de processamento auditivo foram aplicados antes e após os treinamentos. RESULTADOS: Apenas o grupo estudo apresentou melhora significante para todas as habilidades auditivas testadas, mas com piora do desempenho para as habilidades cognitivas. CONCLUSÃO: O treinamento auditivo foi efetivo em relação às habilidades auditivas, mas não em relação às habilidades cognitivas.

  15. 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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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

  16. Levee Presence and Wetland Areas within the 100-Year Floodplain of the Wabash Basin

    Science.gov (United States)

    Morrison, R. R.; Dong, Q.; Nardi, F.; Grantham, T.; Annis, A.

    2016-12-01

    Wetlands have declined over the past century due to land use changes and water management activities in the United States. Levees have been extensively built to provide protection against flooding events, and can fundamentally alter the water distribution and hydrologic dynamics within floodplains. Although levees can reduce wetlands in many places, it is unclear how much wetland areas are impacted at a basin-scale. This study explores the relationship between wetlands, levee presence, and other important hydrologic metrics within a 100-year floodplain. We estimated total wetland area, levee length, floodplain area and other variables, in discrete 12-digit hydrologic units (HUC-12) of the Wabash Basin (n=854) and examined the relationship between these variables using non-parametric statistical tests. We found greater areas of wetland habitat in HUC12 units that contain levees compared to those without levees when we aggregated the results across the entire basin. Factors such as stream order, mean annual flow, and HUC12 area are not correlated with the wetland area in HUC-12 units that contain levees. In addition, median wetland area in HUC12 units with levees is surprisingly consistent regardless of maximum stream order. Visual observations of wetland distributions indicate that wetland presence may be dependent on its location relative to levees. These results indicate that refined geospatial analyses may be necessary to explore the complex influence of levees on wetland habitat, and that additional basins should be explored to develop more generalized trends. This information is preliminary and subject to revision.

  17. Levee Setbacks: An Innovative, Cost Effective, and Sustainable Solution for Improved Flood Risk management

    Science.gov (United States)

    2017-06-30

    ER D C/ EL S R- 17 -3 Levee Setbacks: An Innovative , Cost-Effective, and Sustainable Solution for Improved Flood Risk Management En vi...EL SR-17-3 June 2017 Levee Setbacks: An Innovative , Cost-Effective, and Sustainable Solution for Improved Flood Risk Management David L. Smith...alternative view point is necessary. ERDC/EL SR-17-3 4 Levee setbacks are a relatively recent innovation in Corps flood risk management practice

  18. 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.

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

    Science.gov (United States)

    2010-02-04

    of Flood Protection Update Summary Draft December 2009 Page F-5 soil in unsaturated region. So those equipotential lines above phreatic surface are...Lexington levee where a 50 percent probability of failure is assumed when the water surface is at the top of the levee and a 100 percent chance of failure...is assumed when the water surface is above the top of the levee. Additionally, for cases where the SWL is determined to be the same elevation as

  20. 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...

  1. 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.

  2. 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

  3. 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

  4. Spatial relationships of levees and wetland systems within floodplains of the Wabash Basin, USA

    Science.gov (United States)

    Bray, E. N.; Morrison, R. R.; Nardi, F.; Annis, A.; Dong, Q.

    2017-12-01

    Given the unique biogeochemical, physical, and hydrologic services provided by floodplain wetlands, proper management of river systems should include an understanding of how floodplain modifications influences wetland ecosystems. The construction of levees can reduce river-floodplain connectivity, yet it is unclear how levees affect wetlands within a river system, let alone the cumulative impacts within an entire watershed. This paper explores spatial relationships between levee and floodplain wetland systems in the Wabash basin, United States. We used a hydrogeomorphic floodplain delineation technique to map floodplain extents and identify wetlands that may be hydrologically connected to river networks. We then spatially examined the relationship between levee presence, wetland area, and other river network attributes within discrete HUC-12 sub-basins. Our results show that cumulative wetland area is relatively constant in sub-basins that contain levees, regardless of maximum stream order within the sub-basin. In sub-basins that do not contain levees, cumulative wetland area increases with maximum stream order. However, we found that wetland distributions around levees can be complex, and further studies on the influence of levees on wetland habitat may need to be evaluated at finer-resolution spatial scales.

  5. 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

  6. 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.

  7. 77 FR 9637 - Process for Requesting a Variance From Vegetation Standards for Levees and Floodwalls; Additional...

    Science.gov (United States)

    2012-02-17

    ... revetments, sand dunes, and barrier islands. b. New federally authorized cost-shared levee projects shall be..., the landside slope, and within 15 feet of the landside toe (subject to preexisting real estate... appropriate depth but not less than 20 feet below the levee toe. The determination and documentation of site...

  8. An Approach for Real-time Levee Health Monitoring Using Signal Processing Methods

    NARCIS (Netherlands)

    Pyayt, A.L.; Kozionov, A.P.; Mokhov, I.I.; Lang, B.; Krzhizhanovskaya, V.V.; Sloot, P.M.A.

    2013-01-01

    We developed a levee health monitoring system within the UrbanFlood project funded under the EU 7th Framework Programme. A novel real-time levee health assessment Artificial Intelligence system is developed using data-driven methods. The system is implemented in the UrbanFlood early warning system.

  9. Study of Movement and Seepage Along Levees Using DINSAR and the Airborne UAVSAR Instrument

    Science.gov (United States)

    Jones, Cathleen E.; Bawden, Gerald; Deverel, Steven; Dudas, Joel; Hensley, Scott

    2012-01-01

    We have studied the utility of high resolution SAR (synthetic aperture radar) for levee monitoring using UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) data collected along the dikes and levees in California's Sacramento-San Joaquin Delta and along the lower Mississippi River. Our study has focused on detecting and tracking changes that are indicative of potential problem spots, namely deformation of the levees, subsidence along the levee toe, and seepage through the levees, making use of polarimetric and interferometric SAR techniques. Here was present some results of those studies, which show that high resolution, low noise SAR imaging could supplement more traditional ground-based monitoring methods by providing early indicators of seepage and deformation.

  10. 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.

  11. 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.

  12. 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.

  13. 44 CFR 65.10 - Mapping of areas protected by levee systems.

    Science.gov (United States)

    2010-10-01

    ..., compressibility of embankment soils, compressibility of foundation soils, age of the levee system, and... described in the COE manual, “Soil Mechanics Design—Settlement Analysis” (EM 1100-2-1904) must be submitted...

  14. 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...

  15. 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.

  16. 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.

  17. Levee reliability analyses for various flood return periods - a case study in southern Taiwan

    Science.gov (United States)

    Huang, W.-C.; Yu, H.-W.; Weng, M.-C.

    2015-04-01

    In recent years, heavy rainfall conditions have caused disasters around the world. To prevent losses by floods, levees have often been constructed in inundation-prone areas. This study performed reliability analyses for the Chiuliao First Levee in southern Taiwan. The failure-related parameters were the water level, the scouring depth, and the in situ friction angle. Three major failure mechanisms were considered: the slope sliding failure of the levee and the sliding and overturning failures of the retaining wall. When the variability of the in situ friction angle and the scouring depth are considered for various flood return periods, the variations of the factor of safety for the different failure mechanisms show that the retaining wall sliding and overturning failures are more sensitive to the change of the friction angle. When the flood return period is greater than 2 years, the levee could fail with slope sliding for all values of the water level difference. The results of levee stability analysis considering the variability of different parameters could aid engineers in designing the levee cross sections, especially with potential failure mechanisms in mind.

  18. 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

  19. Erosion versus construction: The origin of Venusian channels

    Science.gov (United States)

    Bussey, D. B. J.; Guest, J. E.

    1992-01-01

    Lava channels are a common feature in the volcanic regions of the Moon, and have now been observed on Venus. There has been much debate about the origin of lunar channels as to whether they are the result of erosional (either thermal or mechanical) or constructional processes. It is necessary to determine the criteria to distinguish between the different types of channels. The clearest evidence is that the presence of levees indicates that the channel experienced a constructional phase for a period. One example of a channel of this type in the southeast region of Aphrodite Terra appears to show both erosional and constructional characteristics. It is approximately 700 km long with an average width of about 1 km. It drops a distance of 700 m from beginning to end, which means that the average slope is 0.06 degrees. Its source may have been a graben situated at the northwest end of the channel. It appears to have different origins along its length. The lack of levees near the source suggests that the channel is erosional in this region. The presence of levees indicates that a constructional phase has occurred. These are formed by lava repeatedly splashing over the channel sides and solidifying. Evidence of levees is seen further away from the source. However, the presence of levees does not mean that the lava was not also eroding and deepening the channel. Thus, in conclusion, our example channel is very sinuous and there is evidence of erosion. There may also have been overflow here. In its middle reaches it roofs over and has the characteristics of a lava tube. In the lower reaches there is strong evidence for the presence of levees indicating construction. On Earth, limited amounts of erosion may occur in basaltic lava channels, although not nearly on the same scale as on the planets just mentioned. For lava erosion on Earth to occur to a comparable extent, excessive eruption times are required. However, low-viscosity komatiite lava may erode to a larger extent

  20. Using ground penetrating radar in levee assessment to detect small scale animal burrows

    Science.gov (United States)

    Chlaib, Hussein K.; Mahdi, Hanan; Al-Shukri, Haydar; Su, Mehmet M.; Catakli, Aycan; Abd, Najah

    2014-04-01

    Levees are civil engineering structures built to protect human lives, property, and agricultural lands during flood events. To keep these important structures in a safe condition, continuous monitoring must be performed regularly and thoroughly. Small rodent burrows are one of the major defects within levees; however, their early detection and repair helps in protecting levees during flooding events. A set of laboratory experiments was conducted to analyze the polarity change in GPR signals in the presence of subsurface voids and water-filled cavities. Ground Penetrating Radar (GPR) surveys using multi frequency antennas (400 MHz and 900 MHz) were conducted along an 875 meter section of the Lollie Levee near Conway, Arkansas, USA, to assess the levee's structural integrity. Many subsurface animal burrows, water-filled cavities, clay clasts, and metallic objects were investigated and identified. These anomalies were located at different depths and have different sizes. To ground truth the observations, hand dug trenches were excavated to confirm several anomalies. Results show an excellent match between GPR interpreted anomalies and the observed features. In-situ dielectric constant measurements were used to calculate the feature depths. The results of this research show that the 900 MHz antenna has more advantages over the 400 MHz antenna.

  1. Accuracy Analysis Comparison of Supervised Classification Methods for Anomaly Detection on Levees Using SAR Imagery

    Directory of Open Access Journals (Sweden)

    Ramakalavathi Marapareddy

    2017-10-01

    Full Text Available This paper analyzes the use of a synthetic aperture radar (SAR imagery to support levee condition assessment by detecting potential slide areas in an efficient and cost-effective manner. Levees are prone to a failure in the form of internal erosion within the earthen structure and landslides (also called slough or slump slides. If not repaired, slough slides may lead to levee failures. In this paper, we compare the accuracy of the supervised classification methods minimum distance (MD using Euclidean and Mahalanobis distance, support vector machine (SVM, and maximum likelihood (ML, using SAR technology to detect slough slides on earthen levees. In this work, the effectiveness of the algorithms was demonstrated using quad-polarimetric L-band SAR imagery from the NASA Jet Propulsion Laboratory’s (JPL’s uninhabited aerial vehicle synthetic aperture radar (UAVSAR. The study area is a section of the lower Mississippi River valley in the Southern USA, where earthen flood control levees are maintained by the US Army Corps of Engineers.

  2. Numerical simulation of pore pressure changes in levee under flood conditions

    Science.gov (United States)

    Stanisz, Jacek; Borecka, Aleksandra; Pilecki, Zenon; Kaczmarczyk, Robert

    2017-11-01

    The article discusses the potential for using numerical simulation to assess the development of deformation and pore pressure changes in a levee as a result of the increase and decrease of the flood wave. The simulation made in FLAC 2D did not take into account the filter-erosion deformation associated with seepage in the levee. The simulations were carried out for a field experimental storage consisting of two combined levees, which was constructed with the help of homogeneous cohesive materials with different filtration coefficients. Calculated and measured pore pressure changes were analysed at 4 monitoring points. The water level was increased to 4 m in 96 hours and decreased in 120 hours. The characteristics of the calculated and measured pore pressure changes over time were similar. The maximum values of the calculated and measured pore pressure were almost identical. The only differences were the greater delay of the experimental levee response to changes in water level increase compared to the response of the numerical model. These differences were probably related to filtering-erosion effects during seepage in the levee.

  3. Condition Assessment of Levees, U.S. Section of the International Boundary and Water Commission. Report 5: Flood Simulation Study of Retamal Levee, Lower Rio Grande Valley, Texas, Using Seismic and Electrical Geophysical Models

    National Research Council Canada - National Science Library

    Dunbar, Joseph B; Llopis, Jose L; Sills, George L; Smith, Eric W; Miller, Rick D; Ivanov, Julian; Corwin, Robert F

    2007-01-01

    In November 2004, a team from the U.S. Army Engineer Research and Development Center conducted a ponding test on a reach of the Retamal levee in the Lower Rio Grande Valley to simulate performance of the levee during a flood event...

  4. 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.

  5. 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......."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....

  6. The egg model - a geological ensemble for reservoir simulation

    NARCIS (Netherlands)

    Jansen, J.D.; Fonseca, R.M.; Kahrobaei, S.; Siraj, M.M.; Essen, van G.M.; Hof, Van den P.M.J.

    2014-01-01

    The ‘Egg Model’ is a synthetic reservoir model consisting of an ensemble of 101 relatively small three-dimensional realizations of a channelized oil reservoir produced under water flooding conditions with eight water injectors and four oil producers. It has been used in numerous publications to

  7. The glaciogenic reservoir analogue studies project (GRASP)

    DEFF Research Database (Denmark)

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

    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...

  8. 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.

  9. SILTATION IN RESERVOIRS

    African Journals Online (AJOL)

    Keywords: reservoir model, siltation, sediment, catchment, sediment transport. 1. Introduction. Sediment ... rendered water storage structures useless in less than 25 years. ... reservoir, thus reducing the space available for water storage and ...

  10. 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

  11. 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

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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

  18. Fortescue reservoir development and reservoir studies

    Energy Technology Data Exchange (ETDEWEB)

    Henzell, S.T.; Hicks, G.J.; Horden, M.J.; Irrgang, H.R.; Janssen, E.J.; Kable, C.W.; Mitchell, R.A.H.; Morrell, N.W.; Palmer, I.D.; Seage, N.W.

    1985-03-01

    The Fortescue field in the Gippsland Basin, offshore southeastern Australia is being developed from two platforms (Fortescue A and Cobia A) by Esso Australia Ltd. (operator) and BHP Petroleum. The Fortescue reservoir is a stratigraphic trap at the top of the Latrobe Group of sediments. It overlies the western flank of the Halibut and Cobia fields and is separated from them by a non-net sequence of shales and coals which form a hydraulic barrier between the two systems. Development drilling into the Fortescue reservoir commenced in April 1983 with production coming onstream in May 1983. Fortescue, with booked reserves of 44 stock tank gigalitres (280 million stock tank barrels) of 43/sup 0/ API oil, is the seventh major oil reservoir to be developed in the offshore Gippsland Basin by Esso/BHP. In mid-1984, after drilling a total of 20 exploration and development wells, and after approximately one year of production, a detailed three-dimensional, two-phase reservoir simulation study was performed to examine the recovery efficiency, drainage patterns, pressure performance and production rate potential of the reservoir. The model was validated by history matching an extensive suite of Repeat Formation Test (RFT) pressure data. The results confirmed the reserves basis, and demonstrated that the ultimate oil recovery from the reservoir is not sensitive to production rate. This result is consistent with studies on other high quality Latrobe Group reservoirs in the Gippsland Basin which contain undersaturated crudes and receive very strong water drive from the Basin-wide aquifer system. With the development of the simulation model during the development phase, it has been possible to more accurately define the optimal well pattern for the remainder of the development.

  19. 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...... dispersion equation in modeling the transport and the deposition of reservoir fines. It successfully predicts the unsymmetrical concentration profiles and the hyperexponential deposition in experiments....

  20. 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.

  1. Using level-I PRA for enhanced safety of the advanced neutron source reactor

    International Nuclear Information System (INIS)

    Ramsey, C.T.; Linn, M.A.

    1995-01-01

    The phase-1, level-I probabilistic risk assessment (PRA) of the Advanced Neutron Source (ANS) reactor has been completed as part of the conceptual design phase of this proposed research facility. Since project inception, PRA and reliability concepts have been an integral part of the design evolutions contributing to many of the safety features in the current design. The level-I PRA has been used to evaluate the internal events core damage frequency against project goals and to identify systems important to safety and availability, and it will continue to guide and provide support to accident analysis, both severe and nonsevere. The results also reflect the risk value of defense-in-depth safety features in reducing the likelihood of core damage

  2. 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.

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

    Science.gov (United States)

    1983-12-01

    services during the event; and postflood reoccupation and recovery. Practically, for rural areas, a plan should be developed and implemented on a county...trends for the area can be seen in the OBERS projections in table 4. Farm employment is projected to continue decreasing while the nonfarm sectors ...report provides the public the initial information needed to assess the potential for Federal involvement in developing ring levees for the

  4. 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...

  5. Avulsions, channel evolution and floodplain sedimentation rates of the anastomosing upper Columbia River, British Columbia, Canada

    NARCIS (Netherlands)

    Makaske, B.; Smith, D.G.; Berendsen, H.J.A.

    2002-01-01

    Ages of channels of the anastomosing upper Columbia River, south-eastern British Columbia, Canada, were investigated in a cross-valley transect by C-14 dating of subsurface floodplain organic material from beneath levees. The avulsion history within the transect was deduced from these data, and

  6. 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.

  7. Formation and maintenance of single-thread tie channels entering floodplain lakes: Observations from three diverse river systems

    Science.gov (United States)

    Rowland, J. C.; Dietrich, W. E.; Day, G.; Parker, G.

    2009-06-01

    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 the following 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. Bidirectional 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.

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. Modeling and analysis of the vertical roots distribution in levees - a case study of the third Rhone correction

    Science.gov (United States)

    Gianetta, Ivan; Schwarz, Massimiliano; Glenz, Christian; Lammeranner, Walter

    2013-04-01

    In recent years the effects of roots on river banks and levees have been the subject of major discussions. The main issue about the presence of woody vegetation on levees is related to the possibility that roots increase internal erosion processes and the superimposed load of large trees compromise the integrity of these structures. However, ecologists and landscape managers argue that eliminating the natural vegetation from the riverbanks also means eliminating biotopes, strengthening anthropisation of the landscape, as well as limiting recreations areas. In the context of the third correction of the Rhone in Switzerland, the discussion on new levee geometries and the implementation of woody vegetation on them, lead to a detailed analysis of this issue for this specific case. The objective of this study was to describe quantitatively the processes and factors that influence the root distribution on levees and test modeling approaches for the simulation of vertical root distribution with laboratory and field data. An extension of an eco-hydrological analytic model that considers climatic and pedological condition for the quantification of vertical root distribution was validated with data provided by the University of Vienna (BOKU) of willows' roots (Salix purpurea) grown under controlled conditions. Furthermore, root distribution data of four transversal sections of a levee near Visp (canton Wallis, Switzerland) was used to validate the model. The positions of the levee's sections were chosen based on the species and dimensions of the woody vegetation. The dominant species present in the sections were birch (Betula pendula) and poplar (Populus nigra). For each section a grid of 50x50 cm was created to count and measure the roots. The results show that vertical distribution of root density under controlled growing conditions has an exponential form, decreasing with increasing soil depth, and can be well described by the eco-hydrological model. Vice versa, field

  14. 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...

  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. "Determinação cromatografica quantitativa de gases leves em hidrogenio"

    OpenAIRE

    Newton Pimenta Neves Jr

    1995-01-01

    Resumo: O hidrogênio ultrapurificado tem sido utilizado em ritmo crescente em diversos processos de alta tecnologia, com destaque para a indústria de micro-eletrônica, onde a presença de impurezas no gás influi decisivamente nos resultados obtidos. Neste trabalho foram desenvolvidos aspectos relacionados à determinação cromatográfica quantitativa de gases leves em hidrogênio. Inicialmente foram desenvolvidas técnicas de amostragem e análise que possibilitam determinar concentrações de até 1mm...

  18. Programa de entrenamiento en habilidades sociales con personas mayores con discapacidad auditiva y visual leve

    OpenAIRE

    García Carracedo, Laura

    2014-01-01

    A partir de la hipótesis de que la mejora en habilidades sociales va a repercutir en mejorar la calidad de vida de las personas mayores, se ha desarrollado un programa de intervención dirigido a personas mayores con discapacidad auditiva y visual leve procedentes de la residencia “Casa Beneficencia” situada en la calle camino del cementerio en Valladolid. En el presente trabajo hemos utilizado diversas técnicas para la recogida de información previa y posterior diagnóstico de las necesidad...

  19. Memoria lexico-semantica no comprometimento cognitivo leve amnestico e doença de Alzheimer leve : aspectos neuropsicologicos, de neuroimagem estrutural e modelo de organização cerebral

    OpenAIRE

    Marcio Luiz Figueredo Balthazar

    2008-01-01

    Resumo: A organização cerebral da memória léxico-semântica, assim como suas alterações em pacientes com doença de Alzheimer (DA) leve e Comprometimento Cognitivo Leve amnéstico (CCLa) não são completamente conhecidas. Neste estudo, avaliamos o desempenho de pacientes com DA leve, CCLa e idosos normais em testes léxico-semânticos como o Teste de Nomeação de Boston (TNB), Teste de Similaridades do CAMCOG e Fluência Verbal (FV) para categoria animais, além de outros domínios cognitivos. Aprofund...

  20. 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.

  1. An inverse method to estimate the flow through a levee breach

    Science.gov (United States)

    D'Oria, Marco; Mignosa, Paolo; Tanda, Maria Giovanna

    2015-08-01

    We propose a procedure to estimate the flow through a levee breach based on water levels recorded in river stations downstream and/or upstream of the failure site. The inverse problem is solved using a Bayesian approach and requires the execution of several forward unsteady flow simulations. For this purpose, we have used the well-known 1-D HEC-RAS model, but any unsteady flow model could be adopted in the same way. The procedure has been tested using four synthetic examples. Levee breaches with different characteristics (free flow, flow with tailwater effects, etc.) have been simulated to collect the synthetic level data used at a later stage in the inverse procedure. The method was able to accurately reproduce the flow through the breach in all cases. The practicability of the procedure was then confirmed applying it to the inundation of the Polesine Region (Northern Italy) which occurred in 1951 and was caused by three contiguous and almost simultaneous breaches on the left embankment of the Po River.

  2. Topographic effect on Radio-Magnetotelluric and Slingram signals: application to a levee along the Loire river, France.

    Science.gov (United States)

    Duval, Rodolphe; Fauchard, Cyrille; Antoine, Raphael

    2014-05-01

    We study the influence of the topography of a levee on the electric and magnetic signals obtained with the Radio-Magnetotelluric method (RMT) and the Slingram method, respectively. For the RMT method, field measurements have been modelled with a finite element commercial software (AC/DC and Radio-Frequency modules of Comsol Multiphysics). A levee situated in Orléans (France) along the Loire river has been considered in order to design a model taking into account the skin depth and the incident wavelength. The effect of the incident electromagnetic field direction has been assessed with two different incident wave directions: BBC 5 from Salford (UK) and France-Inter from Allouis (France). The simulations highlight the tri-dimensional effects of the topography in the apparent resistivity, observed on the crest of the levee, depending on the incident field direction and topography. For the Slingram method, the magnetic field has been simulated using the AC/DC module of Comsol. The ratio of the primary magnetic field on the secondary one, received in a loop is determined above a straight levee. The study aims to show the various responses obtained in function of both vertical and horizontal coil configurations. We show that the signal also depends on the topography and the right configuration of the coils alignment with respect to the levee stretch direction. In this study, a buried gas pipe is also characterized by the two methods. Numerical modelling of 3D electromagnetic effects on geophysical signals helps to interpret the field measurements and offers to the stakeholder an optimized methodology for geophysical surveys on levees.

  3. 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.

  4. 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

  5. Queueing systems with heavy tails (Summary of Ph.D. thesis on the occasion of receiving the Gijs de Leve prize)

    NARCIS (Netherlands)

    Zwart, A.P.

    2003-01-01

    This article gives a short summary of my PhD thesis Queueing Systems with Heavy-tails, winner of the Gijs De Leve prize for the best Dutch thesis in operations research in the period 2000-2002. Apart from the Gijs de Leve prize, this thesis also received the ASML prize, for best thesis in Ihe

  6. Nagylengyel: an interesting reservoir. [Yugoslovia

    Energy Technology Data Exchange (ETDEWEB)

    Dedinszky, J

    1971-04-01

    The Nagylengyel oil field, discovered in 1951, has oil-producing formations mostly in the Upper-Triassic dolomites, in the Norian-Ractian transition formations, in the Upper-Cretaceous limestones and shales, and in the Miocene. The formation of the reservoir space occurred in many stages. A porous, cavernous fractured reservoir is developed in the Norian principal dolomite. A cavernous fractured reservoir exists in the Cretaceous limestone and in the Cretaceous shale and porous fractured reservoir is developed in the Miocene. The derivation of the model of the reservoir, and the conservative evaluation of the volume of the reservoir made it possible to use secondary recovery.

  7. 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.

  8. 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

  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. Application of ground penetrating radar in detecting the hazards and risks of termites and ants in soil levees.

    Science.gov (United States)

    Yang, Xiuhao; Henderson, Gregg; Mao, Lixin; Evans, Ahmad

    2009-08-01

    A ground penetrating radar (GPR) technique was used to detect Formosan subterranean termite (Coptotermes formosanus) and red imported fire ant (Solenopsis invicta) hazards and risks (targets) in a soil levee at the London Avenue Canal in New Orleans, LA. To make this assessment, GPR signal scans were examined for features produced by termite or ant activities and potential sources of food and shelter such as nests, tree roots, and voids (tunnels). The total scanned length of the soil levee was 4,125 m. The average velocity and effective depth of the radar penetration was 0.080 m/ns and 0.61 m, respectively. Four hundred twenty-seven targets were identified. Tree roots (38), voids (31), fire ant nests (209), and metal objects (149) were detected, but no Formosan termite carton nests were identified. The lack of identified termite nests may be related to drowning events at the time to the flood. Based on the target density (TD), the two new floodwall and levee sections that were rebuilt or reinforced after they were destroyed by Hurricane Katrina in 2005 were determined to be at low potential risk from termites and ants. A merging target density (MTD) method indicated a high potential risk near one of the breached sections still remains. Foraging and nesting activity of Formosan subterranean termites and red imported fire ants may be a contributory factor to the levee failure at the London Avenue Canal.

  11. Assessment of earthen levee stability for management and response: A NASA-DHS-California Dept. Water Resources collaboration

    Science.gov (United States)

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

    2016-12-01

    Radar remote sensing of the Sacramento-San Joaquin Delta, the largest estuary in the western U.S. (over 2500 km2), and its levee system provides an opportunity for NASA Applied Science to aid the CA Department of Water Resources (CA-DWR) in monitoring and emergency response. The delta contains over 1,500 km of earthen levees, supports about 2.5 million acres of agricultural land, and serves as a main water supply for 23 million California residents. Many of the reclaimed islands are 10-25 feet below sea level, sit atop compressible peat and organic clay soils, and are surrounded by levees only 1 foot above the once in a century flood elevation threshold. Land subsidence in the delta can be attributed to a variety of factors, including: aerobic oxidation of soils, soil compaction from drainage, wind erosion, anaerobic decomposition, dissolved carbon fluxes, floods, seismic events, and even rodent burrowing. Interferometric Synthetic Aperture Radar (InSAR) is an established technique to measure surface displacements and has been used to map large-scale subsidence. The demonstration of earthen levee monitoring is a recent development that has been greatly furthered by the emergence of new instruments such as NASA's Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR). UAVSAR is an L-band airborne sensor with high signal-to-noise ratio, repeat flight track accuracy, and has a high spatial resolution (7 x 7 m) 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 InSAR with geographic information systems (GIS) datasets in locating subsidence features along critical levee infrastructure in the Delta for 2009-2016. The ability to efficiently locate potential areas of

  12. 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

  13. Detecting fluid leakage of a reservoir dam based on streaming self-potential measurements

    Science.gov (United States)

    Song, Seo Young; Kim, Bitnarae; Nam, Myung Jin; Lim, Sung Keun

    2015-04-01

    Between many reservoir dams for agriculture in suburban area of South Korea, water leakage has been reported several times. The dam under consideration in this study, which is located in Gyeong-buk, in the south-east of the Korean Peninsula, was reported to have a large leakage at the right foot of downstream side of the reservoir dam. For the detection of the leakage, not only geological survey but also geophysical explorations have been made for precision safety diagnosis, since the leakage can lead to dam failure. Geophysical exploration includes both electrical-resistivity and self-potential surveys, while geological surveys water permeability test, standard penetration test, and sampling for undisturbed sample during the course of the drilling investigation. The geophysical explorations were made not only along the top of dam but also transverse the heel of dam. The leakage of water installations can change the known-heterogeneous structure of the dam body but also cause streaming spontaneous (self) potential (SP) anomaly, which can be detected by electrical resistivity and SP measurements, respectively. For the interpretation of streaming SP, we used trial-and-error method by comparing synthetic SP data with field SP data for model update. For the computation, we first invert the resistivity data to obtain the distorted resistivity structure of the dam levee then make three-dimensional electrical-resistivity modeling for the streaming potential distribution of the dam levee. Our simulation algorithm of streaming SP distribution based on the integrated finite difference scheme computes two-dimensional (2D) SP distribution based on the distribution of calculated flow velocities of fluid for a given permeability structure together with physical properties. This permeability is repeatedly updated based on error between synthetic and field SP data, until the synthetic data match the field data. Through this trial-and-error-based SP interpretation, we locate the

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

    KAUST Repository

    Sotelo-Hitschfeld, T.; Niemeyer, M. I.; Machler, P.; Ruminot, I.; Lerchundi, R.; Wyss, M. T.; Stobart, J.; Fernandez-Moncada, I.; Valdebenito, R.; Garrido-Gerter, P.; Contreras-Baeza, Y.; Schneider, B. L.; Aebischer, P.; Lengacher, S.; San Martin, A.; Le Douce, J.; Bonvento, G.; Magistretti, Pierre J.; Sepulveda, F. V.; Weber, B.; Barros, L. F.

    2015-01-01

    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.

  15. Chalk as a reservoir

    DEFF Research Database (Denmark)

    Fabricius, Ida Lykke

    , and the best reservoir properties are typically found in mudstone intervals. Chalk mudstones vary a lot though. The best mudstones are purely calcitic, well sorted and may have been redeposited by traction currents. Other mudstones are rich in very fine grained silica, which takes up pore space and thus...... 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...... have hardly any stylolites and can have porosity above 40% or even 50% and thus also have relatively high permeability. Such intervals have the problem though, that increasing effective stress caused by hydrocarbon production results in mechanical compaction and overall subsidence. Most other chalk...

  16. Work reservoirs in thermodynamics

    International Nuclear Information System (INIS)

    Anacleto, Joaquim

    2010-01-01

    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.

  17. 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.

  18. Sediment transport-storage relations for degrading, gravel bed channels

    Science.gov (United States)

    Thomas E. Lisle; Michael Church

    2002-01-01

    In a drainage network,sediment is transferred through a series of channel/valley segments (natural sediment storage reservoirs) that are distinguished from their neighbors by their particular capacity to store and transport sediment. We propose that the sediment transport capacity of each reservoir is a unique positive function of storage volume, which influences...

  19. 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.

  20. Proceedings of a Hydrology and Hydraulics Workshop on Riverine Levee Freeboard Held in Monticello, Minnesota on 27-29 August 1991

    Science.gov (United States)

    1991-12-10

    Presented by Earl E. Eiker) Headquarters, U.S. Army Corps of Engineers ...................... 5 LEVEE FREEBOARD DEJA VU ALL OVER AGAIN (Paper 2) Brad...0~e a) . Plate PAPE 0 12 LEVEE FREEBOARD DEJA VU ALL OVER AGAIN by Brad Fowler 1 presented by Robert M. Daniel2 1. Introduction. It’s been now nearly... Deja Vu All Over Again (Bob Daniel, HQUSACE) 10:00 - 10:15 am Break 10:15 - 11:00 am Paper 3 FEMA Levee Accreditation Procedures (John Matticks, Asst

  1. 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

  2. Using Chemicals to Optimize Conformance Control in Fractured Reservoirs; TOPICAL

    International Nuclear Information System (INIS)

    Seright, Randall S.; Liang, Jenn-Tai; Schrader, Richard; Hagstrom II, John; Wang, Ying; Kumar, Ananad; Wavrik, Kathryn

    2001-01-01

    This report describes work performed during the third and final year of the project, Using Chemicals to Optimize Conformance Control in Fractured Reservoirs. This research project had three objectives. The first objective was 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 was to develop procedures for optimizing blocking agent placement in wells where hydraulic fractures cause channeling problems. The third objective was to develop procedures to optimize blocking agent placement in naturally fractured reservoirs

  3. 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.

  4. 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.

  5. Levee work for No.3 unit in Ikata Nuclear Power Plant

    International Nuclear Information System (INIS)

    Nakajima, Hiroshi; Matsumoto, Tadashi.

    1987-01-01

    An underwater concreting technique was decided to be used for preventing subsidence of a rubble mound which may occur after the installation of a caison. It was planned to fill the gaps among the rubble stones with a special type of underwater concrete. This report deals with the tests for concrete placing and actual levee work which was carried out based on the test results. Tests are performed to determine the compressive strength, flow properties and self-levelling properties of the concrete. Water analysis is also conducted. Furthermore, examinations are made on the capability of the mixer to be mounted on the vessel, the capacity of the concrete pump and required batches to be fed. A work plan is developed based on these examinations. The actual underwater concrete placing work was carried out as follows: 1) excavation of the foundation ground by a grab dredger, 2) throwing down of rubble stones around the foundation and compaction of them by a heavy weight, 3) shaping of the face of slope, 4) throwing down of additional stons in the central portion, and 5) placing of special underwater concrete. For quality management, measurements of the slump. slump flow and air volume were made and compressive strength testing was performed during the work. The tubidity is also observed. (Nogami, K.)

  6. Detection of Subsurface Defects in Levees in Correlation to Weather Conditions Utilizing Ground Penetrating Radar

    Science.gov (United States)

    Martinez, I. A.; Eisenmann, D.

    2012-12-01

    Ground Penetrating Radar (GPR) has been used for many years in successful subsurface detection of conductive and non-conductive objects in all types of material including different soils and concrete. Typical defect detection is based on subjective examination of processed scans using data collection and analysis software to acquire and analyze the data, often requiring a developed expertise or an awareness of how a GPR works while collecting data. Processing programs, such as GSSI's RADAN analysis software are then used to validate the collected information. Iowa State University's Center for Nondestructive Evaluation (CNDE) has built a test site, resembling a typical levee used near rivers, which contains known sub-surface targets of varying size, depth, and conductivity. Scientist at CNDE have developed software with the enhanced capabilities, to decipher a hyperbola's magnitude and amplitude for GPR signal processing. With this enhanced capability, the signal processing and defect detection capabilities for GPR have the potential to be greatly enhanced. This study will examine the effects of test parameters, antenna frequency (400MHz), data manipulation methods (which include data filters and restricting the range of depth in which the chosen antenna's signal can reach), and real-world conditions using this test site (such as varying weather conditions) , with the goal of improving GPR tests sensitivity for differing soil conditions.

  7. Effect of a levee setback on aquatic resources using two-dimensional flow and bioenergetics models

    Science.gov (United States)

    Black, Robert W.; Czuba, Christiana R.; Magirl, Christopher S.; McCarthy, Sarah; Berge, Hans; Comanor, Kyle

    2016-04-05

    Watershed restoration is the focus of many resource managers and can include a multitude of restoration actions each with specific restoration objectives. For the White River flowing through the cities of Pacific and Sumner, Washington, a levee setback has been proposed to reconnect the river with its historical floodplain to help reduce flood risks, as well as provide increased habitat for federally listed species of salmonids. The study presented here documents the use of a modeling framework that integrates two-dimensional hydraulic modeling with process-based bioenergetics modeling for predicting how changes in flow from reconnecting the river with its floodplain affects invertebrate drift density and the net rate of energy intake of juvenile salmonids. Modeling results were calculated for flows of 25.9 and 49.3 cubic meters per second during the spring, summer, and fall. Predicted hypothetical future mean velocities and depths were significantly lower and more variable when compared to current conditions. The abundance of low energetic cost and positive growth locations for salmonids were predicted to increase significantly in the study reach following floodplain reconnection, particularly during the summer. This modeling framework presents a viable approach for evaluating the potential fisheries benefits of reconnecting a river to its historical floodplain that integrates our understanding of hydraulic, geomorphology, and organismal biology.

  8. 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.

  9. Channel Formation in Physical Experiments: Examples from Deep and Shallow Water Clastic Sedimentary Systems

    Science.gov (United States)

    Hoyal, D. C.; Sheets, B. A.

    2005-12-01

    fundamental channel instability develops in both laminar and turbulent flow but with important differences. The scaling of these effects is the focus of ongoing research. In general it was observed that there are strong similarities between the processes and sedimentary products in shallow and deep water systems. Further, strong channelization in EMURC experiments provides insights into the evolution of distributive systems including: (1) the cyclic process of lobe formation and channel growth at a channel mouth, (2) types of channel fill, (3) architectural differences between channel fill and lobe deposits, (4) channel backfilling and avulsion, (5) Channel initiation vs. entrenched channel phases, (6) knickpoints and channel erosion, (7) structure of overbank, levee-building flows, and (8) the role of levees in altering the distributive channel pattern.

  10. Total flavonoid of Litsea coreana leve exerts anti-oxidative effects and alleviates focal cerebral ischemia/reperfusion injury

    OpenAIRE

    Dong, Shuying; Tong, Xuhui; Li, Jun; Huang, Cheng; Hu, Chengmu; Jiao, Hao; Gu, Yuchen

    2013-01-01

    In this study, we hypothesized that total flavonoid of Litsea coreana leve (TFLC) protects against focal cerebral ischemia/reperfusion injury. TFLC (25, 50, 100 mg/kg) was administered orally to a rat model of focal ischemia/reperfusion injury, while the free radical scavenging agent, edaravone, was used as a positive control drug. Results of neurological deficit scoring, 2,3,5-triphenyl tetrazolium chloride staining, hematoxylin-eosin staining and biochemical tests showed that TFLC at differ...

  11. Encapsulated microsensors for reservoir interrogation

    Science.gov (United States)

    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.

  12. All-optical reservoir computing.

    Science.gov (United States)

    Duport, François; Schneider, Bendix; Smerieri, Anteo; Haelterman, Marc; Massar, Serge

    2012-09-24

    Reservoir Computing is a novel computing paradigm that uses a nonlinear recurrent dynamical system to carry out information processing. Recent electronic and optoelectronic Reservoir Computers based on an architecture with a single nonlinear node and a delay loop have shown performance on standardized tasks comparable to state-of-the-art digital implementations. Here we report an all-optical implementation of a Reservoir Computer, made of off-the-shelf components for optical telecommunications. It uses the saturation of a semiconductor optical amplifier as nonlinearity. The present work shows that, within the Reservoir Computing paradigm, all-optical computing with state-of-the-art performance is possible.

  13. 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.

  14. Canali-type channels on Venus - Some genetic constraints

    Science.gov (United States)

    Komatsu, Goro; Kargel, Jeffrey S.; Baker, Victor R.

    1992-01-01

    Canali-type channels on Venus are unique because of their great lengths (up to 6800 km) and nearly constant channel cross sectional shapes along their paths. A simple model incorporating channel flow and radiative cooling suggests that common terrestrial-type tholeiite lava cannot sustain a superheated and turbulent state for the long distances required for thermal erosion of canali within allowable discharge rates. If canali formed mainly by constructional processes, laminar tholeiitic flow of relatively high, sustained discharge rates might travel the observed distances, but the absence of levees would need to be explained. An exotic low temperature, low viscosity lava like carbonatite or sulfur seems to be required for the erosional genesis of canali.

  15. 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)

  16. Cesium reservoir and interconnective components

    International Nuclear Information System (INIS)

    1994-03-01

    The program objective is to demonstrate the technology readiness of a TFE (thermionic fuel element) suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW range. A thermionic converter must be supplied with cesium vapor for two reasons. Cesium atoms adsorbed on the surface of the emitter cause a reduction of the emitter work function to permit high current densities without excessive heating of the emitter. The second purpose of the cesium vapor is to provide space-charge neutralization in the emitter-collector gap so that the high current densities may flow across the gap unattenuated. The function of the cesium reservoir is to provide a source of cesium atoms, and to provide a reserve in the event that cesium is lost from the plasma by any mechanism. This can be done with a liquid cesium metal reservoir in which case it is heated to the desired temperature with auxiliary heaters. In a TFE, however, it is desirable to have the reservoir passively heated by the nuclear fuel. In this case, the reservoir must operate at a temperature intermediate between the emitter and the collector, ruling out the use of liquid reservoirs. Integral reservoirs contained within the TFE will produce cesium vapor pressures in the desired range at typical electrode temperatures. The reservoir material that appears to be the best able to meet requirements is graphite. Cesium intercalates easily into graphite, and the cesium pressure is insensitive to loading for a given intercalation stage. The goals of the cesium reservoir test program were to verify the performance of Cs-graphite reservoirs in the temperature-pressure range of interest to TFE operation, and to test the operation of these reservoirs after exposure to a fast neutron fluence corresponding to seven year mission lifetime. In addition, other materials were evaluated for possible use in the integral reservoir

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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

  2. Quality and Dose Optimized CT Trauma Protocol - Recommendation from a University Level-I Trauma Center.

    Science.gov (United States)

    Kahn, Johannes; Kaul, David; Böning, Georg; Rotzinger, Roman; Freyhardt, Patrick; Schwabe, Philipp; Maurer, Martin H; Renz, Diane Miriam; Streitparth, Florian

    2017-09-01

    Purpose  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 85 s 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. Results  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 mGyxcm). 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. Conclusion  A dedicated adaptation of the CT trauma protocol (level of reduction of tube voltage and of IR

  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. 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.

  5. Aptidão física de escolares com deficiência intetectual leve

    Directory of Open Access Journals (Sweden)

    Maria Denise Justo Panda

    2016-08-01

    Full Text Available Atualmente, visualizamos muitas escolas com um trabalho significativo e contributivo para o processo de inclusão, com esforços direcionados para o desenvolvimento integral dos alunos com necessidades educacionais especiais nas escolas regulares e a educação física tem um papel importante nesse processo. Objetivo: avaliar a aptidão física relacionada à saúde e ao desempenho esportivo dos escolares diagnosticados com deficiência Intelectual leve, de três escolas participantes do Programa Institucional de Bolsa de Iniciação à Docência – PIBID/UNICRUZ/Educação Física. Método: foram sujeitos do estudo 21 escolares, com idades entre 7 e 15 anos. O instrumento utilizado foi o Manual de testes e avaliação PROESP-BR (Projeto Esporte Brasil. Resultados: as variáveis que avaliaram a saúde dos educandos desencadearam maior preocupação, pois mostraram que a maioria dos alunos das três escolas está na zona de risco, principalmente no IMC (índice de massa corporal, estando eles acima do seu peso ideal, ou seja, com sobrepeso e até casos de obesidade. Outro resultado preocupante foram os índices de flexibilidade que mostram problemas de mobilidade corporal. As variáveis relacionadas ao desempenho esportivo desses alunos não foram tão alarmantes, mas estão aquém do esperado. Considerações finais: os resultados do estudo foram socializados e ofereceram indicadores para um planejamento de atividades, de acordo com as reais necessidades dos alunos, levando em conta que as oficinas de educação psicomotora do PIBID/UNICRUZ/ Educação Física devem apresentar significância para todos os seus participantes.

  6. Channel box

    International Nuclear Information System (INIS)

    Tanabe, Akira.

    1993-01-01

    In a channel box of a BWR type reactor, protruding pads are disposed in axial position on the lateral side of a channel box opposing to a control rod and facing the outer side portion of the control rod in a reactor core loaded state. In the initial loading stage of fuel assemblies, channel fasteners and spacer pads are abutted against each other in the upper portion between the channel boxes sandwiching the control rod therebetween. Further, in the lower portion, a gap as a channel for the movement of the control rod is ensured by the support of fuel support metals. If the channel box is bent toward the control rod along with reactor operation, the pads are abutted against each other to always ensure the gap through which the control rod can move easily. Further, when the pads are brought into contact with each other, the bending deformation of the channel box is corrected by urging to each other. Thus, the control rod can always be moved smoothly to attain reactor safety operation. (N.H.)

  7. 75 FR 6364 - Process for Requesting a Variance From Vegetation Standards for Levees and Floodwalls

    Science.gov (United States)

    2010-02-09

    ..., channels, or shore- line or river-bank protection systems such as revetments, sand dunes, and barrier...) toe (subject to preexisting right-of-way). f. The vegetation variance process is not a mechanism to...

  8. Avoiding The Inevitable? Capacity Loss From Reservoir Sedimentation

    Science.gov (United States)

    Gray, John R.; Randle, Timothy J.; Collins, Kent L.

    2013-01-01

    The inexorable loss of capacity of the nation's reservoirs—sooner or later threatening water supplies for municipal, agricultural, and industrial uses—is but one of a number of deleterious effects wrought by sediment deposition. Trapped sediments can also damage or bury dam outlets, water intakes, and related infrastructure. Downstream effects of sediment capture and retention by reservoirs can include channel and habitat degradation and biotic alterations.

  9. 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

  10. Surface channeling

    International Nuclear Information System (INIS)

    Sizmann, R.; Varelas, C.

    1976-01-01

    There is experimental evidence that swift light ions incident at small angles towards single crystalline surfaces can lose an appreciable fraction of their kinetic energy during reflection. It is shown that these projectiles penetrate into the bulk surface region of the crystal. They can travel as channeled particles along long paths through the solid (surface channeling). The angular distribution and the depth history of the re-emerged projectiles are investigated by computer simulations. A considerable fraction of the penetrating projectiles re-emerges from the crystal with constant transverse energy if the angle of incidence is smaller than the critical angle for axial channeling. Analytical formulae are derived based on a diffusion model for surface channeling. A comparison with experimental data exhibits the relevance of the analytical solutions. (Auth.)

  11. 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.

  12. Spark Channels

    Energy Technology Data Exchange (ETDEWEB)

    Haydon, S. C. [Department of Physics, University of New England, Armidale, NSW (Australia)

    1968-04-15

    A brief summary is given of the principal methods used for initiating spark channels and the various highly time-resolved techniques developed recently for studies with nanosecond resolution. The importance of the percentage overvoltage in determining the early history and subsequent development of the various phases of the growth of the spark channel is discussed. An account is then given of the recent photographic, oscillographic and spectroscopic investigations of spark channels initiated by co-axial cable discharges of spark gaps at low [{approx} 1%] overvoltages. The phenomena observed in the development of the immediate post-breakdown phase, the diffuse glow structure, the growth of the luminous filament and the final formation of the spark channel in hydrogen are described. A brief account is also given of the salient features emerging from corresponding studies of highly overvolted spark gaps in which the spark channel develops from single avalanche conditions. The essential differences between the two types of channel formation are summarized and possible explanations of the general features are indicated. (author)

  13. Lexical semantic memory in amnestic mild cognitive impairment and mild Alzheimer's disease Memória léxico-semântica no comprometimento cognitivo leve amnéstico e doença de Alzheimer leve

    Directory of Open Access Journals (Sweden)

    Marcio L.F. Balthazar

    2007-09-01

    Full Text Available OBJECTIVE: To study lexical semantic memory in patients with amnestic mild cognitive impairment (aMCI, mild Alzheimer's disease (AD and normal controls. METHOD: Fifteen mild AD, 15 aMCI, and 15 normal control subjects were included. Diagnosis of AD was based on DSM-IV and NINCDS-ADRDA criteria, and that of aMCI, on the criteria of the International Working Group on Mild Cognitive Impairment, using CDR 0.5 for aMCI and CDR 1 for mild AD. All subjects underwent semantic memory tests (Boston Naming-BNT, CAMCOG Similarities item, Rey Auditory Verbal Learning Test (RAVLT, Mini-Mental Status Examination (MMSE, neuropsychological tests (counterproofs, and Cornell Scale for Depression in Dementia. Data analysis used Mann-Whitney test for intergroup comparisons and Pearson's coefficient for correlations between memory tests and counterproofs (statistical significance level was pOBJETIVO: Estudar a memória léxico-semântica no comprometimento cognitivo leve amnéstico (aCCL, doença de Alzheimer (DA leve e controles normais. MÉTODO: Incluímos 15 pacientes com DA leve, 15 com aCCL e 15 controles normais, usando os critérios DSM-IV, NINCDS-ADRDA e CDR 1 para DA, e os do International Working Group on Mild Cognitive Impairment, e CDR 0,5 para aCCL. Todos os sujeitos passaram por testes de memória semântica (Teste de nomeação de Boston - TNB, item de Similaridades do CAMCOG, teste de aprendizado auditivo-verbal de Rey (TAAVR, Mini-Exame do Estado Mental (MEEM, testes neuropsicológicos (contraprovas e Escala Cornell para Depressão em Demência. A análise dos dados usou o teste de Mann-Whitney para comparações entre os grupos e o coeficiente de Pearson para correlação entre testes e contraprovas (nível de significância p<0,05. RESULTADOS: Os pacientes com aCCL foram semelhantes aos controles no TNB e Similaridades, mas inferiores no MEEM e TAAVR. Pacientes com DA leve tiveram performance inferior à de sujeitos com aCCL e controles em todos os

  14. Calibration of Seismic Attributes for Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-01-29

    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.

  15. Understanding the True Stimulated Reservoir Volume in Shale Reservoirs

    KAUST Repository

    Hussain, Maaruf; Saad, Bilal; Negara, Ardiansyah; Sun, Shuyu

    2017-01-01

    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

  16. Determinação da exigência nutricional de treonina para poedeiras leves e semipesadas

    Directory of Open Access Journals (Sweden)

    Valerio Sandra Roselí

    2000-01-01

    Full Text Available Desenvolveu-se este experimento com o objetivo de determinar a exigência nutricional de treonina para poedeiras leves e semipesadas no período de 21 a 36 semanas. Foram utilizadas 576 aves, 288 poedeiras leves e 288 semipesadas, durante quatro períodos experimentais de 28 dias cada. O delineamento experimental foi inteiramente casualizado em esquema fatorial 6 x 2 (níveis x marcas, com seis repetições e oito aves por unidade experimental. Os tratamentos consistiram em uma ração basal contendo 14,2% de proteína bruta, suplementada com cinco níveis de L-treonina (0,025; 0,050; 0,075; 0,100; e 0,125%, resultando em um total de 0,510; 0,535; 0,560; 0,585; 0,610; e 0,635% de treonina. O desempenho produtivo e a qualidade interna dos ovos foram avaliados. Consumo de ração, produção de ovos massa de ovos e o ganho de peso foram superiores para as poedeiras semipesadas. A produção e qualidade interna dos ovos, a conversão alimentar e o ganho de peso não foram influenciados pelos níveis de treonina utilizados. O nível de 0,510% de treonina, que corresponde a 515 mg/ave/dia (0,423% de treonina digestível e 535 mg/ave/dia (0,440% de treonina digestível, foi suficiente para atender, satisfatoriamente, o desempenho e a qualidade interna dos ovos das poedeiras leves e semipesadas, respectivamente, para as características avaliadas.

  17. Iron speciation and mineral characterization of upper Jurassic reservoir rocks in the Minhe Basin, NW China

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiangxian; Zheng, Guodong, E-mail: gdzhbj@mail.iggcas.ac.cn; Xu, Wang [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Liang, Minliang [Chinese Academy of Geological Sciences, Institute of Geomechanics, Key Lab of Shale Oil and Gas Geological Survey (China); Fan, Qiaohui; Wu, Yingzhong; Ye, Conglin [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Shozugawa, Katsumi; Matsuo, Motoyuki [The University of Tokyo, Graduate School of Arts and Sciences (Japan)

    2016-12-15

    Six samples from a natural outcrop of reservoir rocks with oil seepage and two control samples from surrounding area in the Minhe Basin, northwestern China were selectively collected and analyzed for mineralogical composition as well as iron speciation using X-ray powder diffraction (XRD) and Mössbauer spectroscopy, respectively. Iron species revealed that: (1) the oil-bearing reservoir rocks were changed by water-rock-oil interactions; (2) even in the same site, there was a different performance between sandstone and mudstone during the oil and gas infusion to the reservoirs; and (3) this was evidence indicating the selective channels of hydrocarbon migration. In addition, these studies showed that the iron speciation by Mössbauer spectroscopy could be useful for the study of oil and gas reservoirs, especially the processes of the water-rock interactions within petroleum reservoirs.

  18. 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

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

    International Nuclear Information System (INIS)

    Kahn, Johannes; Boening, Georg; Rotzinger, Roman; Freyhardt, Patrick; Streitparth, Florian; Kaul, David; Schwabe, Philipp; Maurer, Martin H.; Renz, Diane Miriam

    2017-01-01

    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. Efecto de la restitución temprana de la nutrición oral en la pancreatitis aguda leve

    OpenAIRE

    Vega Sandoval, Carlos Andres; Isaza Restrepo, Andres; Moscoso Daza, Alejandro

    2010-01-01

    Aunque el manejo nutricional de los pacientes con Pancreatitis Aguda Severa ha sido bien establecido por la evidencia disponible, el inicio de la vía oral en Pancreatitis Leve no ha sido igualmente estudiado. El objetivo de este estudio es evaluar el efecto del inicio temprano de la nutrición por vía oral en estos pacientes. Métodos: Realizamos un descriptivo serie de comparación de casos en los cuales comparamos la evolución y resultados del manejo de los pacientes con pancreatitis aguda ant...

  1. The elusive character of discontinuous deep-water channels: New insights from Lucia Chica channel system, offshore California

    Science.gov (United States)

    Maier, K.L.; Fildani, A.; Paull, C.K.; Graham, S.A.; McHargue, T.R.; Caress, D.W.; McGann, M.

    2011-01-01

    New high-resolution autonomous underwater vehicle (AUV) seafloor images, with 1 m lateral resolution and 0.3 m vertical resolution, reveal unexpected seafloor rugosity and low-relief (thalwegs were interpreted originally from lower-resolution images, but newly acquired AUV data indicate that a single sinuous channel fed a series of discontinuous lower-relief channels. These discontinuous channels were created by at least four avulsion events. Channel relief, defined as the height from the thalweg to the levee crest, controls avulsions and overall stratigraphic architecture of the depositional area. Flowstripped turbidity currents separated into and reactivated multiple channels to create a distributary pattern and developed discontinuous trains of cyclic scours and megaflutes, which may be erosional precursors to continuous channels. The diverse features now imaged in the Lucia Chica channel system (offshore California) are likely common in modern and ancient systems with similar overall morphologies, but have not been previously mapped with lower-resolution detection methods in any of these systems. ?? 2011 Geological Society of America.

  2. Design Techniques and Reservoir Simulation

    Directory of Open Access Journals (Sweden)

    Ahad Fereidooni

    2012-11-01

    Full Text Available Enhanced oil recovery using nitrogen injection is a commonly applied method for pressure maintenance in conventional reservoirs. Numerical simulations can be practiced for the prediction of a reservoir performance in the course of injection process; however, a detailed simulation might take up enormous computer processing time. In such cases, a simple statistical model may be a good approach to the preliminary prediction of the process without any application of numerical simulation. In the current work, seven rock/fluid reservoir properties are considered as screening parameters and those parameters having the most considerable effect on the process are determined using the combination of experimental design techniques and reservoir simulations. Therefore, the statistical significance of the main effects and interactions of screening parameters are analyzed utilizing statistical inference approaches. Finally, the influential parameters are employed to create a simple statistical model which allows the preliminary prediction of nitrogen injection in terms of a recovery factor without resorting to numerical simulations.

  3. The Characteristics of Spanish Reservoirs

    National Research Council Canada - National Science Library

    Armengol, J; Merce, R

    2003-01-01

    Sau Reservoir was first filled in 1963 in a middle stretch of the Ter River, as part of a multi-use scheme, including hydroelectric power, agricultural irrigation, domestic and industrial water supply...

  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. 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.

  7. 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.

  8. A rationale for reservoir management economics

    International Nuclear Information System (INIS)

    Hickman, T.S.

    1995-01-01

    Significant economic benefits can be derived from the application f reservoir management. The key elements in economical reservoir management are the efficient use of available resources and optimization of reservoir exploitation through a multidisciplined approach. This paper describes various aspects of and approaches to reservoir management and provides case histories that support the findings

  9. 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.

  10. Concreto leve com pérolas de EPS: estudo de dosagens e de características mecânicas

    OpenAIRE

    Bianca Pereira Moreira Ozório

    2016-01-01

    Este trabalho teve como objetivo analisar o comportamento do concreto leve com pérolas de poliestireno expandido (expanded polystyrene – EPS), para posterior utilização em estruturas pré-moldadas constituídas, por exemplo, por painéis de paredes e lajes sujeitas a ações mecânicas. Também foram considerados parâmetros de durabilidade e mecanismos de redução da porosidade. Dentre um universo de solicitações a que as estruturas de concreto leve podem estar submetidas, analisaram-se, para d...

  11. 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.

  12. 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

  13. 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)

  14. 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.

  15. Multilevel techniques for Reservoir Simulation

    DEFF Research Database (Denmark)

    Christensen, Max la Cour

    The subject of this thesis is the development, application and study of novel multilevel methods for the acceleration and improvement of reservoir simulation techniques. The motivation for addressing this topic is a need for more accurate predictions of porous media flow and the ability to carry...... Full Approximation Scheme) • Variational (Galerkin) upscaling • Linear solvers and preconditioners First, a nonlinear multigrid scheme in the form of the Full Approximation Scheme (FAS) is implemented and studied for a 3D three-phase compressible rock/fluids immiscible reservoir simulator...... 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...

  16. 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

  17. 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

  18. 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...

  19. Actual Condition of Paddy Field Levee Maintenance by Various Farm Households including Large-scale Farming in the Developed Land Renting Area

    Science.gov (United States)

    Sakata, Yasuyo

    The survey of interview, resource acquisition, photographic operation, and questionnaire were carried out in the “n” Community in the “y” District in Hakusan City in Ishikawa Prefecture to investigate the actual condition of paddy field levee maintenance in the area where land-renting market was proceeding, large-scale farming was dominant, and the problems of geographically scattered farm-land existed. In the study zone, 1) an agricultural production legal person rent-cultivated some of the paddy fields and maintained the levees, 2) another agricultural production legal person rent-cultivated some of the soy bean fields for crop changeover and land owners maintained the levees. The results indicated that sufficient maintenance was executed on the levees of the paddy fields cultivated by the agricultural production legal person, the soy bean fields for crop changeover, and the paddy fields cultivated by the land owners. Each reason is considered to be the managerial strategy, the economic incentive, the mutual monitoring and cross-regulatory mechanism, etc.

  20. Prevention of Reservoir Interior Discoloration

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, K.F.

    2001-04-03

    Contamination is anathema in reservoir production. Some of the contamination is a result of welding and some appears after welding but existed before. Oxygen was documented to be a major contributor to discoloration in welding. This study demonstrates that it can be controlled and that some of the informal cleaning processes contribute to contamination.

  1. Nonlinear Multigrid for Reservoir Simulation

    DEFF Research Database (Denmark)

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

    2016-01-01

    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...

  2. Variability of morphological conditions of the Vistula river channel in the section Czerwińsk-Kępa Polska

    Directory of Open Access Journals (Sweden)

    Popek Zbigniew

    2015-03-01

    Full Text Available Variability of morphological conditions of the Vistula river channel in the section Czerwińsk-Kępa Polska. The paper presents an assessment of morphological changes that occurred in the Vistula river channel in selected section of about 33 km long, located in the middle of the Vistula river course between Czerwińsk and Kępa Polska (km 576–609. Based on the analysis of archival material from 1972–2009, a characteristics of river channel changes, taking primarily into account the horizontal layout (shape in the plan, was obtained. An attempt was made to estimate the trends and rate of transformation of the following parameters in the river channel: width, length, and position of the riverbanks, abundance and size of islands and fluvial deposits, as well as their percentage in the total area of the main river channel and the floodplain area between levees.

  3. 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...

  4. RECENT ADVANCES IN NATURALLY FRACTURED RESERVOIR MODELING

    OpenAIRE

    ORDOÑEZ, A; PEÑUELA, G; IDROBO, E. A; MEDINA, C. E

    2001-01-01

    Large amounts of oil reserves are contained in naturally fractured reservoirs. Most of these hydrocarbon volumes have been left behind because of the poor knowledge and/or description methodology of those reservoirs. This lack of knowledge has lead to the nonexistence of good quantitative models for this complicated type of reservoirs. The complexity of naturally fractured reservoirs causes the need for integration of all existing information at all scales (drilling, well logging, seismic, we...

  5. Reservoir resistivity characterization incorporating flow dynamics

    KAUST Repository

    Arango, Santiago; Sun, Shuyu; Hoteit, Ibrahim; Katterbauer, Klemens

    2016-01-01

    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.

  6. 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.

  7. Channelling and electromagnetic radiation of channelling particles

    International Nuclear Information System (INIS)

    Kalashnikov, N.

    1983-01-01

    A brief description is presented of the channelling of charged particles between atoms in the crystal lattice. The specificities are discussed of the transverse motion of channelling particles as are the origin and properties of quasi-characteristic radiation of channelling particles which accompany transfers from one band of permissible energies of the transverse motion of channelling particles to the other. (B.S.)

  8. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    Nurhandoko, Bagus Endar B., E-mail: bagusnur@bdg.centrin.net.id, E-mail: bagusnur@rock-fluid.com [Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Basic Science Center A 4" t" hfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia); Susilowati, E-mail: bagusnur@bdg.centrin.net.id, E-mail: bagusnur@rock-fluid.com [Rock Fluid Imaging Lab., Bandung (Indonesia)

    2015-04-16

    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.

  10. 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

  11. Channel Modeling

    Science.gov (United States)

    Schmitz, Arne; Schinnenburg, Marc; Gross, James; Aguiar, Ana

    For any communication system the Signal-to-Interference-plus-Noise-Ratio of the link is a fundamental metric. Recall (cf. Chapter 9) that the SINR is defined as the ratio between the received power of the signal of interest and the sum of all "disturbing" power sources (i.e. interference and noise). From information theory it is known that a higher SINR increases the maximum possible error-free transmission rate (referred to as Shannon capacity [417] of any communication system and vice versa). Conversely, the higher the SINR, the lower will be the bit error rate in practical systems. While one aspect of the SINR is the sum of all distracting power sources, another issue is the received power. This depends on the transmitted power, the used antennas, possibly on signal processing techniques and ultimately on the channel gain between transmitter and receiver.

  12. Channeling experiment

    International Nuclear Information System (INIS)

    Abelin, H.; Birgersson, L.; Widen, H.; Aagren, T.; Moreno, L.; Neretnieks, I.

    1990-07-01

    Channeling of water flow and tracer transport in real fractures in a granite body at Stripa have been investigated experimentally. The experimental site was located 360 m below the ground level. Two kinds of experiments were performed. In the single hole experiments, 20 cm diameter holes were drilled about 2.5 m into the rock in the plane of the fracture. Specially designed packers were used to inject water into the fracture in 5 cm intervals all along the fracture trace in the hole. The variation of the injection flowrates along the fracture were used to determine the transmissivity variations in the fracture plane. Detailed photographs were taken from inside the hole and the visual fracture aperture was compared with the injection flowrates in the same locations. Geostatistical methods were used to evaluate the results. Five holes were measured in great detail. In addition 7 holes were drilled and scanned by simpler packer systems. A double hole experiment was performed where two parallel holes were drilled in the same fracture plane at nearly 2 m distance. Pressure pulse tests were made between the holes in both directions. Tracers were injected in 5 locations in one hole and monitored for in many locations in the other hole. The single hole experiment and the double hole experiment show that most of the fracture planes are tight but that there are open sections which form connected channels over distances of at least 2 meters. It was also found in the double hole experiment that the investigated fracture was intersected by at least one fracture between the two holes which diverted a large amount of the injected tracers to several distant locations at the tunnel wall. (authours)

  13. 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

  14. 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

  15. 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.

  16. 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. 

  17. 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.

  18. Williston Reservoir raising - environmental overview

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-01

    This preliminary environmental overview report was prepared by B.C. Hydro in June 1987 and revised in July 1988 as an initial assessment of a possible 1.5 m (5 ft.) raise in the Williston Reservoir maximum normal level. The enviromental overview study and the associated engineering and property studies were undertaken to provide information for a decision on whether to initiate more detailed studies. Overview studies are based mainly on available reports, mapping and field data, supplemented by limited site reconnaissance and, in this case, input from key agencies and groups. The lack of adequate mapping of areas which could be affected by reservoir raising did not permit definitive conclusion to be reached. This mapping will be done over the next year to complete the overview assessment. This document covers the impact assessment of socio-economic factors, forestry, reservoir clearing, heritage, recreation, aquatic resources, and wilflife. Further studies in each of these areas are also included. 54 refs., 11 figs., 8 tabs.

  19. Reservoir floodplains support distinct fish assemblages

    Science.gov (United States)

    Miranda, Leandro E.; Wigen, S. L.; Dagel, Jonah D.

    2014-01-01

    Reservoirs constructed on floodplain rivers are unique because the upper reaches of the impoundment may include extensive floodplain environments. Moreover, reservoirs that experience large periodic water level fluctuations as part of their operational objectives seasonally inundate and dewater floodplains in their upper reaches, partly mimicking natural inundations of river floodplains. In four flood control reservoirs in Mississippi, USA, we explored the dynamics of connectivity between reservoirs and adjacent floodplains and the characteristics of fish assemblages that develop in reservoir floodplains relative to those that develop in reservoir bays. Although fish species richness in floodplains and bays were similar, species composition differed. Floodplains emphasized fish species largely associated with backwater shallow environments, often resistant to harsh environmental conditions. Conversely, dominant species in bays represented mainly generalists that benefit from the continuous connectivity between the bay and the main reservoir. Floodplains in the study reservoirs provided desirable vegetated habitats at lower water level elevations, earlier in the year, and more frequently than in bays. Inundating dense vegetation in bays requires raising reservoir water levels above the levels required to reach floodplains. Therefore, aside from promoting distinct fish assemblages within reservoirs and helping promote diversity in regulated rivers, reservoir floodplains are valued because they can provide suitable vegetated habitats for fish species at elevations below the normal pool, precluding the need to annually flood upland vegetation that would inevitably be impaired by regular flooding. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  20. 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.

  1. 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.

  2. 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.

  3. A Volcanic Origin for Sinuous and Branching Channels on Mars: Evidence from Hawaiian Analogs

    Science.gov (United States)

    Bleacher, Jacob E.; deWet, Andrew; Garry, W. Brent; Zimbelman, James R.

    2012-01-01

    Observations of sinuous and branching channels on planets have long driven a debate about their origin, fluvial or volcanic processes. In some cases planetary conditions rule out fluvial activity (e.g. the Moon, Venus, Mercury). However, the geology of Mars leads to suggestions that liquid water existed on the surface in the past. As a result, some sinuous and branching channels on Mars are cited as evidence of fluvial erosion. Evidence for a fluvial history often focuses on channel morphologies that are unique from a typical lava channel, for instance, a lack of detectable flow margins and levees, islands and terraces. Although these features are typical, they are not necessarily diagnostic of a fluvial system. We conducted field studies in Hawaii to characterize similar features in lava flows to better define which characteristics might be diagnostic of fluvial or volcanic processes. Our martian example is a channel system that originates in the Ascraeus Mons SW rift zone from a fissure. The channel extends for approx.300 km to the SE/E. The proximal channel displays multiple branches, islands, terraces, and has no detectable levees or margins. We conducted field work on the 1859 and 1907 Mauna Loa flows, and the Pohue Bay flow. The 51-km-long 1859 Flow originates from a fissure and is an example of a paired a a and pahoehoe lava flow. We collected DGPS data across a 500 m long island. Here, the channel diverted around a pre-existing obstruction in the channel, building vertical walls up to 9 m in height above the current channel floor. The complicated emplacement history along this channel section, including an initial a a stage partially covered by pahoehoe overflows, resulted in an appearance of terraced channel walls, no levees and diffuse flow margins. The 1907 Mauna Loa flow extends > 20 km from the SW rift zone. The distal flow formed an a a channel. However the proximal flow field comprises a sheet that experienced drainage and sagging of the crust

  4. 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...

  5. 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.

  6. Dry Stream Reaches in Carbonate Terranes: Surface Indicators of Ground-Water Reservoirs

    Science.gov (United States)

    Brahana, J.V.; Hollyday, E.F.

    1988-01-01

    In areas where dry stream reaches occur, subsurface drainage successfully competes with surface drainage, and sheet-like dissolution openings have developed parallel to bedding creating the ground-water reservoir. Union Hollow in south-central Tennessee is the setting for a case study that illustrates the application of the dry stream reach technique. In this technique, dry stream reach identification is based on two types of readily acquired information: remotely sensed black and white infrared aerial photography; and surface reconnaissance of stream channel characteristics. Test drilling in Union Hollow subsequent to identification of the dry reach proved that a localized ground-water reservoir was present.

  7. Environmental Assessment: PL 84-99 Levee Rahabilitation Program Lower Platte South Natural Resource District Salt Creek, Lincoln, Lancaster County, Nebraska

    Science.gov (United States)

    2015-03-01

    142+00 to 144+00. These areas are located approximately 1,000 feet south of Rosa Parks Way and the photos show sags and sinkholes on the landside...sloughing and slides, lost sod, displaced riprap, and sinkhole development to portions of the right and left descending banks of Salt Creek. 1.4 AUTHORITY... sinkhole development. The proposed project repairs include reshaping the levee banks back to a 3:1 slope and replacing lost bank material with compacted

  8. 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...

  9. Le cône sous-marin du Nil et son réseau de chenaux profonds : nouveaux résultats (campagne Fanil)The Nile Cone and its channel system: new results after the Fanil cruise

    Science.gov (United States)

    Bellaiche, Gilbert; Loncke, Lies; Gaullier, Virginie; Mascle, Jean; Courp, Thierry; Moreau, Alain; Radan, Silviu; Sardou, Olivier

    2001-10-01

    The meandrous leveed channels of the Nile Cone show clear evidence of avulsions. Their sedimentary architecture is founded on numerous stacked lens-shaped acoustic units. In the areas of the distal fan, lobe deposits are apparent from multichannel imagery. Huge debris flow deposits, sometimes associated with pockmarks, are recognized. Mud volcanoes and gas seeping are closely associated with faulting. In the East, a very long north-trending channel, originating from the Egyptian coast, merges with a network of channels, very probably originating from the Levantine coasts. Both networks outlet in the sedimentary basin located south of Cyprus.

  10. Global Carbon Reservoir Oxidative Ratios

    Science.gov (United States)

    Masiello, C. A.; Gallagher, M. E.; Hockaday, W. C.

    2010-12-01

    Photosynthesis and respiration move carbon and oxygen between the atmosphere and the biosphere at a ratio that is characteristic of the biogeochemical processes involved. This ratio is called the oxidative ratio (OR) of photosynthesis and respiration, and is defined as the ratio of moles of O2 per moles of CO2. This O2/CO2 ratio is a characteristic of biosphere-atmosphere gas fluxes, much like the 13C signature of CO2 transferred between the biosphere and the atmosphere has a characteristic signature. OR values vary on a scale of 0 (CO2) to 2 (CH4), with most ecosystem values clustered between 0.9 and 1.2. Just as 13C can be measured for both carbon fluxes and carbon pools, OR can also be measured for fluxes and pools and can provide information about the processes involved in carbon and oxygen cycling. OR values also provide information about reservoir organic geochemistry because pool OR values are proportional to the oxidation state of carbon (Cox) in the reservoir. OR may prove to be a particularly valuable biogeochemical tracer because of its ability to couple information about ecosystem gas fluxes with ecosystem organic geochemistry. We have developed 3 methods to measure the OR of ecosystem carbon reservoirs and intercalibrated them to assure that they yield accurate, intercomparable data. Using these tools we have built a large enough database of biomass and soil OR values that it is now possible to consider the implications of global patterns in ecosystem OR values. Here we present a map of the natural range in ecosystem OR values and begin to consider its implications. One striking pattern is an apparent offset between soil and biospheric OR values: soil OR values are frequently higher than that of their source biomass. We discuss this trend in the context of soil organic geochemistry and gas fluxes.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. Muon Tomography of Deep Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Bonneville, Alain H.; Kouzes, Richard T.

    2016-12-31

    Imaging subsurface geological formations, oil and gas reservoirs, mineral deposits, cavities or magma chambers under active volcanoes has been for many years a major quest of geophysicists and geologists. Since these objects cannot be observed directly, different indirect geophysical methods have been developed. They are all based on variations of certain physical properties of the subsurface that can be detected from the ground surface or from boreholes. Electrical resistivity, seismic wave’s velocities and density are certainly the most used properties. If we look at density, indirect estimates of density distributions are performed currently by seismic reflection methods - since the velocity of seismic waves depend also on density - but they are expensive and discontinuous in time. Direct estimates of density are performed using gravimetric data looking at variations of the gravity field induced by the density variations at depth but this is not sufficiently accurate. A new imaging technique using cosmic-ray muon detectors has emerged during the last decade and muon tomography - or muography - promises to provide, for the first time, a complete and precise image of the density distribution in the subsurface. Further, this novel approach has the potential to become a direct, real-time, and low-cost method for monitoring fluid displacement in subsurface reservoirs.

  18. Smart waterflooding in carbonate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Zahid, A.

    2012-02-15

    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 in porous media. The main conclusion of most previous studies was that it is the rock wettability alteration towards more water wetting condition that helps improving the oil recovery. In the first step of this project, we focused on verifying this conclusion. Coreflooding experiments were carried out using Stevens Klint outcrop chalk core plugs with brines without sulfate, as well as brines containing sulfate in different concentrations. The effects of temperature, injection rate, crude oil composition and different sulfate concentrations on the total oil recovery and the recovery rate were investigated. Experimental results clearly indicate improvement of the oil recovery without wettability alteration. At the second step of this project, we studied crude oil/brine interactions under different temperatures, pressures and salinity conditions in order to understand mechanisms behind the high salinity waterflooding. Our results show, in particular that sulfate ions may help decreasing the crude oil viscosity or formation of, seemingly, an emulsion phase between sulfate-enriched brine and oil at high temperature and pressure. Experimental results indicate that crude oils interact differently with the same brine solutions regarding phase behavior and viscosity measurements. This difference is attributed to the difference in composition of the different crude oils. More experiments

  19. 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.

  20. 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.

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

    KAUST Repository

    Katterbauer, Klemens; Hoteit, Ibrahim

    2014-01-01

    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

  2. Multi-data reservoir history matching for enhanced reservoir forecasting and uncertainty quantification

    KAUST Repository

    Katterbauer, Klemens; Arango, Santiago; Sun, Shuyu; Hoteit, Ibrahim

    2015-01-01

    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

  3. 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.

  4. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, Roy; Clarke, Don; Walker, Scott

    1999-11-09

    The objectives of this quarterly report was to summarize the work conducted under each task during the reporting period April - June 1998 and to report all technical data and findings as specified in the ''Federal Assistance Reporting Checklist''. The main objective of this project is the transfer of technologies, methodologies, and findings developed and applied in this project to other operators of Slope and Basin Clastic Reservoirs. This project will study methods to identify sands with high remaining oil saturation and to recomplete existing wells using advanced completion technology.

  5. 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.

  6. 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.

  7. 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

  8. Mild cognitive impairment: cognitive screening or neuropsychological assessment? Comprometimento cognitivo leve: rastreio cognitivo ou avaliação neuropsicológica?

    Directory of Open Access Journals (Sweden)

    Breno Satler Diniz

    2008-12-01

    Full Text Available OBJECTIVE: To describe the neuropsychological profile of mild cognitive impairment subtypes (amnestic, non-amnestic and multiple-domain of a clinical sample. We further address the diagnostic properties of the Mini-Mental State Examination and the Cambridge Cognitive Examination for the identification of the different mild cognitive impairment subtypes in clinical practice. METHOD: Cross-sectional clinical and neuropsychological evaluation of 249 elderly patients attending a memory clinic at a university hospital in Sao Paulo, Brazil. RESULTS: The performance of patients with mild cognitive impairment was heterogeneous across the different subtests of the neuropsychological battery, with a trend towards an overall worse performance for amnestic (particularly multiple domain mild cognitive impairment as compared to non-amnestic subtypes. Screening tests for dementia (Mini-Mental State Examination and Cambridge Cognitive Examination adequately discriminated cases of mild Alzheimer's disease from controls, but they were not accurate to discriminate patients with mild cognitive impairment (all subtypes from control subjects. CONCLUSIONS: The discrimination of mild cognitive impairment subtypes was possible only with the aid of a comprehensive neuropsychological assessment. It is necessary to develop new strategies for mild cognitive impairment screening in clinical practice.OBJETIVO: Descrever o perfil neuropsicológico dos subtipos de comprometimento cognitivo leve, amnéstico, não-amnéstico e múltiplos domínios, de uma amostra clínica. Além disto, avaliou-se as propriedades diagnósticas do Mini-exame do Estado Mental e do Cambridge Cognitive Examination na identificação dos diferentes subtipos de comprometimento cognitivo leve na prática clínica. MÉTODO: Avaliação clínica e neuropsicológica transversal de 249 idosos em uma clínica de memória de um hospital universitário em São Paulo, Brasil. RESULTADOS: Testes de rastreio para

  9. 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

  10. Citizens and service channels: channel choice and channel management implications

    NARCIS (Netherlands)

    Pieterson, Willem Jan

    2010-01-01

    The arrival of electronic channels in the 1990s has had a huge impact on governmental service delivery. The new channels have led to many new opportunities to improve public service delivery, not only in terms of citizen satisfaction, but also in cost reduction for governmental agencies. However,

  11. Smart Waterflooding in Carbonate Reservoirs

    DEFF Research Database (Denmark)

    Zahid, Adeel

    brine solutions regarding phase behavior and viscosity measurements. This difference is attributed to the difference in composition of the different crude oils. More experiments are carried out in order to understand mechanisms of the crude oil viscosity reduction and emulsion formation. We observed...... with and without aging. The total oil recovery, recovery rate and interaction mechanisms of ions with rock were studied for different injected fluids under different temperatures and wettability conditions. Experimental results demonstrate that the oil recovery mechanism under high salinity seawater flooding...... phase could be the possible reasons for the observed increase in oil recovery with sulfate ions at high temperature in chalk reservoirs, besides the mechanism of the rock wettability alteration. * Crude oil/brine interaction study suggests that viscosity reduction for crude oil in contact with brine...

  12. Reservoirs talk to pressure recorders

    Energy Technology Data Exchange (ETDEWEB)

    Pamenter, C B

    1968-02-01

    Keeping pace with increased demand for efficiency in secondary recovery schemes is the widening use of downhole tools charged with supplying data before and during the operation of the projects. One of the most important of these is the pressure recorder. This highly sensitive instrument, housed in a tough, slim steel case and lowered by drill pipe or cable, accurately measures the pressure of its downhole environment. This information is instantly available at the surface whenever a pressure reading is required. Typical applications of surface recorders often contribute are: (1) production practices such as checking surface and subsurface equipment, and special lifting problems; (2) well conditions including regular productivity indices, data observations and for interference studies; (3) secondary recovery projects, in both producing and injection wells; and (4) reservoir conditions where oil-water contacts and damaged zones need close attention.

  13. Production Optimization of Oil Reservoirs

    DEFF Research Database (Denmark)

    Völcker, Carsten

    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...... the uid ow. We discretize the the two-phase ow model spatially using the nite volume method (FVM), and we use the two point ux approximation (TPFA) and the single-point upstream (SPU) scheme for computing the uxes. We propose a new formulation of the differential equation system that arise...... as a consequence of the spatial discretization of the two-phase ow model. Upon discretization in time, the proposed equation system ensures the mass conserving property of the two-phase ow model. For the solution of the spatially discretized two-phase ow model, we develop mass conserving explicit singly diagonally...

  14. 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.

  15. 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.

  16. 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.

  17. Estimating Western U.S. Reservoir Sedimentation

    Science.gov (United States)

    Bensching, L.; Livneh, B.; Greimann, B. P.

    2017-12-01

    Reservoir sedimentation is a long-term problem for water management across the Western U.S. Observations of sedimentation are limited to reservoir surveys that are costly and infrequent, with many reservoirs having only two or fewer surveys. This work aims to apply a recently developed ensemble of sediment algorithms to estimate reservoir sedimentation over several western U.S. reservoirs. The sediment algorithms include empirical, conceptual, stochastic, and processes based approaches and are coupled with a hydrologic modeling framework. Preliminary results showed that the more complex and processed based algorithms performed better in predicting high sediment flux values and in a basin transferability experiment. However, more testing and validation is required to confirm sediment model skill. This work is carried out in partnership with the Bureau of Reclamation with the goal of evaluating the viability of reservoir sediment yield prediction across the western U.S. using a multi-algorithm approach. Simulations of streamflow and sediment fluxes are validated against observed discharges, as well as a Reservoir Sedimentation Information database that is being developed by the US Army Corps of Engineers. Specific goals of this research include (i) quantifying whether inter-algorithm differences consistently capture observational variability; (ii) identifying whether certain categories of models consistently produce the best results, (iii) assessing the expected sedimentation life-span of several western U.S. reservoirs through long-term simulations.

  18. 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.

  19. 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.

  20. 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)

  1. 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.

  2. 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

  3. 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

  4. Morphology of channels and channel-sand bodies in the Glauconitic sandstone member (Upper Mannville), Little Bow area, Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, J.C.; Hermanson, S.W.; Lawton, D.C.

    1982-12-01

    Large channels in the Glauconitic sandstone member of southern Alberta have proved to be difficult exploration targets because of an irregular distribution of reservoir sands within the channels. In the Little Bow area, two channels are present in the lower part of the Glauconitic member and have cut into the underlying Calcareous member. The channels can be recognized where they truncate regional markers of the Calcareous member -- the Bantry shale and Ostracod limestone, and where channel-fill deposits exhibit uniform geophysical log characters, indicating sandstone- or mudstone-filled reaches. Sediments of the Glauconitic member adjacent to the channels comprise a series of splay sandstones and mudstones that prograded into interdistributary bays of the lower delta plain. The two channels associated with these deposits are interpreted as distributary channels. Sand bodies within the channels formed as lateral bars and are isolated by mudstones which mark the abandoned stream course. Geological exploration for these discontinuous channel sandstones is difficult, and high-resolutio seismic data integrated with sound geologic modelling are critical for successful prospect delineation.

  5. The freshwater reservoir effect in radiocarbon dating

    DEFF Research Database (Denmark)

    Philippsen, Bente

    2013-01-01

    of magnitude and 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 14C years can occur within one river. The freshwater reservoir effect has also implications......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...

  6. Reservoir model for the Alameda Central waterflood

    Energy Technology Data Exchange (ETDEWEB)

    Randall, T E

    1968-01-01

    The basic approach used in developing the model to characterize the Alameda Central Unit Waterflood assumes continuity of the reservoir mechanics with time. The past performance was analyzed to describe the reservoir and future performance was assumed to follow the established patterns. To develop a mathematical picture of the Alameda Central Unit reservoir, a two-dimensional single-phase steady-state model was used in conjunction with material balance calculations, real-time conversion methods and oil-water interface advance calculations. The model was developed to optimize water injection allocation, determine the configuration of the frontal advance and evaluate the success of the waterflood. The model also provides a basis for continuing review and revision of the basic concepts of reservoir operation. The results of the reservoir study have confirmed the apparent lack of permeability orientation in the pool and indicate that the waterflood is progressing better than originally anticipated.

  7. Visualized study of thermochemistry assisted steam flooding to improve oil recovery in heavy oil reservoir with glass micromodels

    NARCIS (Netherlands)

    Lyu, X.; Liu, Huiqing; Pang, Zhanxi; Sun, Zhixue

    2018-01-01

    Steam channeling, one serious problem in the process of steam flooding in heavy oil reservoir, decreases the sweep efficiency of steam to cause a lower oil recovery. Viscosity reducer and nitrogen foam, two effective methods to improve oil recovery with different mechanism, present a satisfactory

  8. RAPID Assessment of Extreme Reservoir Sedimentation Resulting from the September 2013 Flood, North St. Vrain Creek, CO

    Science.gov (United States)

    Rathburn, S. L.; McElroy, B. J.; Wohl, E.; Sutfin, N. A.; Huson, K.

    2014-12-01

    During mid-September 2013, approximately 360 mm of precipitation fell in the headwaters of the North St. Vrain drainage basin, Front Range, CO. Debris flows on steep hillslopes and extensive flooding along North St. Vrain Creek resulted in extreme sedimentation within Ralph Price Reservoir, municipal water supply for the City of Longmont. The event allows comparison of historical sedimentation with that of an unusually large flood because 1) no reservoir flushing has been conducted since dam construction, 2) reservoir stratigraphy chronicles uninterrupted delta deposition, and 3) this is the only on-channel reservoir with unimpeded, natural sediment flux from the Continental Divide to the mountain front in a basin with no significant historic flow modifications and land use impacts. Assessing the flood-related sedimentation prior to any dredging activities included coring the reservoir delta, a bathymetric survey of the delta, resistivity and ground penetrating radar surveys of the subaerial inlet deposit, and surveying tributary deposits. Over the 44-year life of the reservoir, two-thirds of the delta sedimentation is attributed to extreme discharges from the September 2013 storm. Total storm-derived reservoir sedimentation is approximately 275,000 m3, with 81% of that within the gravel-dominated inlet and 17% in the delta. Volumes of deposition within reservoir tributary inlets is negatively correlated with contributing area, possibly due to a lack of storage in these small basins (1-5 km2). Flood-related reservoir sedimentation will be compared to other research quantifying volumes from slope failures evident on post-storm lidar. Analysis of delta core samples will quantify organic carbon flux associated with the extreme discharge and develop a chronology of flood and fire disturbances for North St. Vrain basin. Applications of similar techniques are planned for two older Front Range reservoirs affected by the September flooding to fill knowledge gaps about

  9. 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.

  10. Reservoir Models for Gas Hydrate Numerical Simulation

    Science.gov (United States)

    Boswell, R.

    2016-12-01

    Scientific and industrial drilling programs have now providing detailed information on gas hydrate systems that will increasingly be the subject of field experiments. The need to carefully plan these programs requires reliable prediction of reservoir response to hydrate dissociation. Currently, a major emphasis in gas hydrate modeling is the integration of thermodynamic/hydrologic phenomena with geomechanical response for both reservoir and bounding strata. However, also critical to the ultimate success of these efforts is the appropriate development of input geologic models, including several emerging issues, including (1) reservoir heterogeneity, (2) understanding of the initial petrophysical characteristics of the system (reservoirs and seals), the dynamic evolution of those characteristics during active dissociation, and the interdependency of petrophysical parameters and (3) the nature of reservoir boundaries. Heterogeneity is ubiquitous aspect of every natural reservoir, and appropriate characterization is vital. However, heterogeneity is not random. Vertical variation can be evaluated with core and well log data; however, core data often are challenged by incomplete recovery. Well logs also provide interpretation challenges, particularly where reservoirs are thinly-bedded due to limitation in vertical resolution. This imprecision will extend to any petrophysical measurements that are derived from evaluation of log data. Extrapolation of log data laterally is also complex, and should be supported by geologic mapping. Key petrophysical parameters include porosity, permeability and it many aspects, and water saturation. Field data collected to date suggest that the degree of hydrate saturation is strongly controlled by/dependant upon reservoir quality and that the ratio of free to bound water in the remaining pore space is likely also controlled by reservoir quality. Further, those parameters will also evolve during dissociation, and not necessary in a simple

  11. 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

  12. 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

  13. 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)

  14. 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.

  15. 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.

  16. 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.

  17. Integrating gravimetric and interferometric synthetic aperture radar data for enhancing reservoir history matching of carbonate gas and volatile oil reservoirs

    KAUST Repository

    Katterbauer, Klemens; Arango, Santiago; Sun, Shuyu; Hoteit, Ibrahim

    2016-01-01

    Reservoir history matching is assuming a critical role in understanding reservoir characteristics, tracking water fronts, and forecasting production. While production data have been incorporated for matching reservoir production levels

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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

  4. Optimal Operation of Hydropower Reservoirs under Climate Change: The Case of Tekeze Reservoir, Eastern Nile

    Directory of Open Access Journals (Sweden)

    Fikru Fentaw Abera

    2018-03-01

    Full Text Available Optimal operation of reservoirs is very essential for water resource planning and management, but it is very challenging and complicated when dealing with climate change impacts. The objective of this paper was to assess existing and future hydropower operation at the Tekeze reservoir in the face of climate change. In this study, a calibrated and validated Soil and Water Assessment Tool (SWAT was used to model runoff inflow into the Tekeze hydropower reservoir under present and future climate scenarios. Inflow to the reservoir was simulated using hydro-climatic data from an ensemble of downscaled climate data based on the Coordinated Regional climate Downscaling Experiment over African domain (CORDEX-Africa with Coupled Intercomparison Project Phase 5 (CMIP5 simulations under Representative Concentration Pathway (RCP4.5 and RCP8.5 climate scenarios. Observed and projected inflows to Tekeze hydropower reservoir were used as input to the US Army Corps of Engineer’s Reservoir Evaluation System Perspective Reservoir Model (HEC-ResPRM, a reservoir operation model, to optimize hydropower reservoir release, storage and pool level. Results indicated that climate change has a clear impact on reservoir inflow and showed increase in annual and monthly inflow into the reservoir except in dry months from May to June under RCP4.5 and RCP8.5 climate scenarios. HEC-ResPRM optimal operation results showed an increase in Tekeze reservoir power storage potential up to 25% and 30% under RCP4.5 and RCP8.5 climate scenarios, respectively. This implies that Tekeze hydropower production will be affected by climate change. This analysis can be used by water resources planners and mangers to develop reservoir operation techniques considering climate change impact to increase power production.

  5. 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

  6. 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.

  7. 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. ...

  8. Time scales of change in chemical and biological parameters after engineered levee breaches adjacent to Upper Klamath and Agency Lakes, Oregon

    Science.gov (United States)

    Kuwabara, James S.; Topping, Brent R.; Carter, James L.; Wood, Tamara M.; Parcheso, Francis; Cameron, Jason M.; Asbill, Jessica R.; Carlson, Rick A.; Fend, Steven V.

    2012-01-01

    Eight sampling trips were coordinated after engineered levee breaches hydrologically reconnected both Upper Klamath Lake and Agency Lake, Oregon, to adjacent wetlands. The reconnection, by a series of explosive blasts, was coordinated by The Nature Conservancy to reclaim wetlands that had for approximately seven decades been leveed for crop production. Sets of nonmetallic porewater profilers (U.S. Patent 8,051,727 B1; November 8, 2011; http://www.uspto.gov/web/patents/patog/ week45/OG/html/1372-2/US08051727-20111108.html.) were deployed during these trips in November 2007, June 2008, May 2009, July 2009, May 2010, August 2010, June 2011, and July 2011 (table 1). Deployments temporally spanned the annual cyanophyte bloom of Aphanizomenon flos-aquae and spatially involved three lake and four wetland sites. Spatial and temporal variation in solute benthic flux was determined by the field team, using the profilers, over an approximately 4-year period beginning 3 days after the levee breaches. The highest flux to the water column of dissolved organic carbon (DOC) was detected in the newly flooded wetland, contrasting negative or insignificant DOC fluxes at adjacent lake sites. Over the multiyear study, DOC benthic fluxes dissipated in the reconnected wetlands, converging to values similar to those for established wetlands and to the adjacent lake (table 2). In contrast to DOC, benthic sources of soluble reactive phosphorus, ammonium, dissolved iron and manganese from within the reconnected wetlands were consistently elevated (that is, significant in magnitude relative to riverine and established-wetland sources) indicating a multi-year time scale for certain chemical changes after the levee breaches (table 2). Colonization of the reconnected wetlands by aquatic benthic invertebrates during the study trended toward the assemblages in established wetlands, providing further evidence of a multiyear transition of this area to permanent aquatic habitat (table 3). Both the

  9. Rehabilitación por el ejercicio de la escoliosis idiopática leve en niños y adolescentes

    OpenAIRE

    Bertoncelli, María Laura

    2013-01-01

    La Sociedad Internacional para el Estudio de la Escoliosis (Scoliosis Research Society) la define como "una curvatura lateral de la columna con rotación de las vértebras dentro de la curva". La escoliosis idiopática es una patología de origen multifactorial que causa una alteración en la postura corporal. La indicación de diferentes técnicas de gimnasia postural ha sido una práctica habitual como parte del tratamiento conservador de la escoliosis idiopática leve(EIL) en niños y adolescente...

  10. TRANSFER RESERVOIR AS A RAINWATER DRAINAGE SYSTEM

    Directory of Open Access Journals (Sweden)

    Robert Malmur

    2016-06-01

    Full Text Available Intensive rainfalls and snow melting often cause floods in protected areas and overflow the existing sewage systems. Such cases are particularly burdensome for the inhabitants and cause considerable physical losses. One of the possible constructional solutions to ensure the effective outflow of stormwater are transfer reservoirs located between the draining system and a receiver set discussed in this paper. If gravity outflow of sewage is impossible, the initial part of sewage volume is accumulated in the transfer reservoir and then it is transferred into the water receiver set. However, gravity discharge of sewage to the water receiver set occurs through transfer chambers in the transfer reservoir.

  11. Non-Markovian reservoir-dependent squeezing

    International Nuclear Information System (INIS)

    Paavola, J

    2010-01-01

    The squeezing dynamics of a damped harmonic oscillator are studied for different types of environment without making the Markovian approximation. The squeezing dynamics of a coherent state depend on the reservoir spectrum in a unique way that can, in the weak coupling approximation, be analysed analytically. Comparison of squeezing dynamics for ohmic, sub-ohmic and super-ohmic environments is done, showing a clear connection between the squeezing-non-squeezing oscillations and reservoir structure. Understanding the effects occurring due to structured reservoirs is important both from a purely theoretical point of view and in connection with evolving experimental techniques and future quantum computing applications.

  12. 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)

  13. Gasbuggy reservoir evaluation - 1969 report

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson, C H; Ward, Don C [Bureau of Mines, U.S. Department of the Interior (United States); Lemon, R F [El Paso Natural Gas Company (United States)

    1970-05-01

    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)

  14. USACE Navigation Channels 2012

    Data.gov (United States)

    California Natural Resource Agency — This dataset represents both San Francisco and Los Angeles District navigation channel lines. All San Francisco District channel lines were digitized from CAD files...

  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 page, please enable JavaScript. Calcium-channel blockers are a type of medicine used ...

  16. 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)

  17. Eight channel fast scalar

    Energy Technology Data Exchange (ETDEWEB)

    Waddoup, W D; Stubbs, R J [Durham Univ. (UK)

    1977-11-01

    An eight channel 64-bit scaler has been constructed with a static CMOS memory. Scaling frequencies are independently variable, at each channel, as are the number of bits/channel. The scaler, when used in conjunction with a multichannel charge to time converter results in a very flexible, gated multichannel ADC.

  18. 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...

  19. 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

  20. 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.

  1. Assembling evidence for identifying reservoirs of infection.

    Science.gov (United States)

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

    2014-05-01

    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. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. 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...

  3. determination of verticality of reservoir engineering structure

    African Journals Online (AJOL)

    user

    applications is 3D survey and management of oil and gas facilities and other engineering structures. This recent .... also affect ground water contamination. 2. VERTICALITY ...... The soil, water and concrete in a Reservoir at the foundation bed ...

  4. Reservoir Greenhouse Gas Emissions at Russian HPP

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, M. P.; Elistratov, V. V.; Maslikov, V. I.; Sidorenko, G. I.; Chusov, A. N.; Atrashenok, V. P.; Molodtsov, D. V. [St. Petersburg State Polytechnic University (Russian Federation); Savvichev, A. S. [Russian Academy of Sciences, S. N. Vinogradskii Institute of Microbiology (Russian Federation); Zinchenko, A. V. [A. I. Voeikov Main Geophysical Observatory (Russian Federation)

    2015-05-15

    Studies of greenhouse-gas emissions from the surfaces of the world’s reservoirs, which has demonstrated ambiguity of assessments of the effect of reservoirs on greenhouse-gas emissions to the atmosphere, is analyzed. It is recommended that greenhouse- gas emissions from various reservoirs be assessed by the procedure “GHG Measurement Guidelines for Fresh Water Reservoirs” (2010) for the purpose of creating a data base with results of standardized measurements. Aprogram for research into greenhouse-gas emissions is being developed at the St. Petersburg Polytechnic University in conformity with the IHA procedure at the reservoirs impounded by the Sayano-Shushenskaya and Mainskaya HPP operated by the RusHydro Co.

  5. Refined reservoir description to maximize oil recovery

    International Nuclear Information System (INIS)

    Flewitt, W.E.

    1975-01-01

    To assure maximized oil recovery from older pools, reservoir description has been advanced by fully integrating original open-hole logs and the recently introduced interpretive techniques made available through cased-hole wireline saturation logs. A refined reservoir description utilizing normalized original wireline porosity logs has been completed in the Judy Creek Beaverhill Lake ''A'' Pool, a reefal carbonate pool with current potential productivity of 100,000 BOPD and 188 active wells. Continuous porosity was documented within a reef rim and cap while discontinuous porous lenses characterized an interior lagoon. With the use of pulsed neutron logs and production data a separate water front and pressure response was recognized within discrete environmental units. The refined reservoir description aided in reservoir simulation model studies and quantifying pool performance. A pattern water flood has now replaced the original peripheral bottom water drive to maximize oil recovery

  6. 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.

  7. Data Compression of Hydrocarbon Reservoir Simulation Grids

    KAUST Repository

    Chavez, Gustavo Ivan; Harbi, Badr M.

    2015-01-01

    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

  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......The freshwater reservoir effect can result in too high radiocarbon ages of samples from lakes and rivers, including the bones of people whose subsistence was based on freshwater fish, and pottery in which fish was cooked. In my talk, I will explain the causes and consequences of this effect. Two...... 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. 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.

  10. Lower Palaeozoic reservoirs of North Africa

    Energy Technology Data Exchange (ETDEWEB)

    Crossley, R.; McDougall, N. [Robertson Research International Ltd., Llandudno, Conwy (United Kingdom)

    1998-12-31

    This paper provides an overview of features considered significant in the exploration and development of Lower Palaeozoic reservoirs of North Africa. Information is derived from a review of literature on the Lower Palaeozoic successions of North Africa, combined with outcrop observations from the Anti Atlas mountains of Morocco. The focus of the exploration-oriented part of the review is on identification of potential traps other than two-way structural dip closure. Stratigraphic elements described include depositional models of reservoir facies, tectonic unconformities and possible eustatic unconformities. Cases of established or potential trapping by post-depositional faulting by diagenesis and by hydrodynamic flow are examined. Development-related topics highlighted include the impact on reservoir matrix quality of burial diagenesis and of palaeo-weathering at the Hercynian unconformity. Other issues discussed which additionally affect producibility from the reservoir matrix include tectonic fracturing, palaeotopography and unloading fracturing at the Hercynian unconformity, and induced fracturing within the present stress regimes. (author)

  11. 49 CFR 393.50 - Reservoirs required.

    Science.gov (United States)

    2010-10-01

    ... using air or vacuum braking must have either reserve capacity, or a reservoir, that would enable the... have a condensate drain valve that can be manually operated. Automatic condensate drain valves may be...

  12. 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

  13. limnological study of the Guavio Reservoir (Colombia)

    International Nuclear Information System (INIS)

    Roldan, Gabriel; Bohorquez, Amparo; Catano, Ramiro; Ardila, Jorge I

    2000-01-01

    From September to December 1996, a limnological study of el Guavio reservoir from o to 100m deep was undertaken. Samples of plankton were taken and chlorophyll a determined. The study showed a well-mixed column of water. Dissolved oxygen remained 60% saturation at 100m deep. Values of phosphorus and nitrogen, as well chlorophyll was very low. Phytoplankton and zooplankton were diverse. The main problem of the reservoir is sediments coming from very erossionable surroundings

  14. Pollination Reservoirs in Lowbush Blueberry (Ericales: Ericaceae)

    OpenAIRE

    Venturini, E. M.; Drummond, F. A.; Hoshide, A. K.; Dibble, A. C.; Stack, L. B.

    2017-01-01

    Abstract Pollinator-dependent agriculture heavily relies upon a single pollinator?the honey bee. To diversify pollination strategies, growers are turning to alternatives. Densely planted reservoirs of pollen- and nectar-rich flowers (pollination reservoirs, hereafter ?PRs?) may improve pollination services provided by wild bees. Our focal agroecosystem, lowbush blueberry (Vaccinium angustifolium Aiton), exists in a simple landscape uniquely positioned to benefit from PRs. First, we contrast b...

  15. Ecological operation for Three Gorges Reservoir

    Directory of Open Access Journals (Sweden)

    Wen-xian Guo

    2011-06-01

    Full Text Available The traditional operation of the Three Gorges Reservoir has mainly focused on water for flood control, power generation, navigation, water supply, and recreation, and given less attention to the negative impacts of reservoir operation on the river ecosystem. In order to reduce the negative influence of reservoir operation, ecological operation of the reservoir should be studied with a focus on maintaining a healthy river ecosystem. This study considered ecological operation targets, including maintaining the river environmental flow and protecting the spawning and reproduction of the Chinese sturgeon and four major Chinese carps. Using flow data from 1900 to 2006 at the Yichang gauging station as the control station data for the Yangtze River, the minimal and optimal river environmental flows were analyzed, and eco-hydrological targets for the Chinese sturgeon and four major Chinese carps in the Yangtze River were calculated. This paper proposes a reservoir ecological operation model, which comprehensively considers flood control, power generation, navigation, and the ecological environment. Three typical periods, wet, normal, and dry years, were selected, and the particle swarm optimization algorithm was used to analyze the model. The results show that ecological operation modes have different effects on the economic benefit of the hydropower station, and the reservoir ecological operation model can simulate the flood pulse for the requirements of spawning of the Chinese sturgeon and four major Chinese carps. According to the results, by adopting a suitable re-operation scheme, the hydropower benefit of the reservoir will not decrease dramatically while the ecological demand is met. The results provide a reference for designing reasonable operation schemes for the Three Gorges Reservoir.

  16. Analog readout for optical reservoir computers

    OpenAIRE

    Smerieri, Anteo; Duport, François; Paquot, Yvan; Schrauwen, Benjamin; Haelterman, Marc; Massar, Serge

    2012-01-01

    Reservoir computing is a new, powerful and flexible machine learning technique that is easily implemented in hardware. Recently, by using a time-multiplexed architecture, hardware reservoir computers have reached performance comparable to digital implementations. Operating speeds allowing for real time information operation have been reached using optoelectronic systems. At present the main performance bottleneck is the readout layer which uses slow, digital postprocessing. We have designed a...

  17. Geophysical monitoring in a hydrocarbon reservoir

    Science.gov (United States)

    Caffagni, Enrico; Bokelmann, Goetz

    2016-04-01

    Extraction of hydrocarbons from reservoirs demands ever-increasing technological effort, and there is need for geophysical monitoring to better understand phenomena occurring within the reservoir. Significant deformation processes happen when man-made stimulation is performed, in combination with effects deriving from the existing natural conditions such as stress regime in situ or pre-existing fracturing. Keeping track of such changes in the reservoir is important, on one hand for improving recovery of hydrocarbons, and on the other hand to assure a safe and proper mode of operation. Monitoring becomes particularly important when hydraulic-fracturing (HF) is used, especially in the form of the much-discussed "fracking". HF is a sophisticated technique that is widely applied in low-porosity geological formations to enhance the production of natural hydrocarbons. In principle, similar HF techniques have been applied in Europe for a long time in conventional reservoirs, and they will probably be intensified in the near future; this suggests an increasing demand in technological development, also for updating and adapting the existing monitoring techniques in applied geophysics. We review currently available geophysical techniques for reservoir monitoring, which appear in the different fields of analysis in reservoirs. First, the properties of the hydrocarbon reservoir are identified; here we consider geophysical monitoring exclusively. The second step is to define the quantities that can be monitored, associated to the properties. We then describe the geophysical monitoring techniques including the oldest ones, namely those in practical usage from 40-50 years ago, and the most recent developments in technology, within distinct groups, according to the application field of analysis in reservoir. This work is performed as part of the FracRisk consortium (www.fracrisk.eu); this project, funded by the Horizon2020 research programme, aims at helping minimize the

  18. Distributary channel meandering and bifurcation patterns on the Amazon deep-sea fan as revealed by long-range side-scan sonar (GLORIA)

    Science.gov (United States)

    Damuth, John E.; Kolla, Venkatarathnam; Flood, Roger D.; Kowsmann, Renato O.; Monteiro, Marcelo C.; Gorini, Marcus A.; Palma, Jorge J. C.; Belderson, Robert H.

    1983-02-01

    We mapped the distributary channel system of the Amazon deep-sea fan using the GLORIA long-range side-scan sonar. Individual channels were continuously traced for distances of up to 150 km. Channel bifurcation, although observed in only a few places, results in many cases from breaching of channel levees on the outsides of meander loops. Whether both channels remain active after branching or the original channel is abandoned by avulsion generally cannot be determined. The most striking channel characteristic is high sinuosity that results in extensive, intricate, often recurving meanders. Cutoffs and abandoned meander loops (oxbows) are observed in a few places. These meandering channels are comparable in size and appearance to those of mature fluvial systems on land, such as on the lower Mississippi River. The formation, maintenance, and modification of such extensive, well-developed meander systems would seem to require large volumes of continuous turbidity flow through the channels for relatively long time periods. This may challenge the traditional concept that channel formation and modification are accomplished by intermittent or sporadic turbidity-current events. *Present address: Superior Oil Company, 12401 Westheimer, Houston, Texas 77077

  19. 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.

  20. 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

  1. 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)

  2. Resultados preliminares do tratamento dos pacientes submetidos a radiofreqüência (baixa freqüência, somnoplastia no ronco e apnéia leve do sono

    Directory of Open Access Journals (Sweden)

    Dibbern Ralph S.

    2002-01-01

    Full Text Available Introdução: O ronco afeta 5 a 50% da população tornando-se um problema médico e social importante. O tratamento pode ser com medidas comportamentais, CPAP e cirúrgico. Objetivo: Avaliar os resultados pós-operatórios dos pacientes submetidos à radiofreqüência em palato. Forma de estudo: retrospectivo clínico. Material e método: 28 pacientes submetidos à radio-freqüência em palato, com diagnóstico de Ronco e Apnéia Leve do Sono. Observamos os resultados pós-operatórios através das Escalas de Epworth, Ronco e Sonolência diurna, complicações e percentual de melhora dos sintomas. A análise estatística foi pelo Mann Whytney Test. Resultados: 16 pacientes com melhora subjetiva do Ronco acima de 70% após a cirurgia; 26 pacientes mostraram redução significativa pelas Escalas, com complicações mínimas. Conclusão: Radio-freqüência é um método seguro e eficaz no tratamento do Ronco e Apnéia Leve do Sono. Resultados melhores serão obtidos com avaliação criteriosa pré e pós-operatórias.

  3. 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.

  4. Massachusetts reservoir simulation tool—User’s manual

    Science.gov (United States)

    Levin, Sara B.

    2016-10-06

    IntroductionThe U.S. Geological Survey developed the Massachusetts Reservoir Simulation Tool to examine the effects of reservoirs on natural streamflows in Massachusetts by simulating the daily water balance of reservoirs. The simulation tool was developed to assist environmental managers to better manage water withdrawals in reservoirs and to preserve downstream aquatic habitats.

  5. 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.

  6. 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)

  7. Fine Channel Networks

    Science.gov (United States)

    1997-01-01

    A color image of fine channel networks on Mars; north toward top. The scene shows heavily cratered highlands dissected by dendritic open channel networks that dissect steep slopes of impact crater walls. This image is a composite of Viking high-resolution images in black and white and low-resolution images in color. The image extends from latitude 9 degrees S. to 5 degrees S. and from longitude 312 degrees to 320 degrees; Mercator projection. The dendritic pattern of the fine channels and their location on steep slopes leads to the interpretation that these are runoff channels. The restriction of these types of channels to ancient highland rocks suggests that these channels are old and date from a time on Mars when conditions existed for precipitation to actively erode rocks. After the channels reach a low plain, they appear to end. Termination may have resulted from burial by younger deposits or perhaps the flows percolated into the surface materials and continued underground.

  8. 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.

  9. Ion channels in plants.

    Science.gov (United States)

    Hedrich, Rainer

    2012-10-01

    Since the first recordings of single potassium channel activities in the plasma membrane of guard cells more than 25 years ago, patch-clamp studies discovered a variety of ion channels in all cell types and plant species under inspection. Their properties differed in a cell type- and cell membrane-dependent manner. Guard cells, for which the existence of plant potassium channels was initially documented, advanced to a versatile model system for studying plant ion channel structure, function, and physiology. Interestingly, one of the first identified potassium-channel genes encoding the Shaker-type channel KAT1 was shown to be highly expressed in guard cells. KAT1-type channels from Arabidopsis thaliana and its homologs from other species were found to encode the K(+)-selective inward rectifiers that had already been recorded in early patch-clamp studies with guard cells. Within the genome era, additional Arabidopsis Shaker-type channels appeared. All nine members of the Arabidopsis Shaker family are localized at the plasma membrane, where they either operate as inward rectifiers, outward rectifiers, weak voltage-dependent channels, or electrically silent, but modulatory subunits. The vacuole membrane, in contrast, harbors a set of two-pore K(+) channels. Just very recently, two plant anion channel families of the SLAC/SLAH and ALMT/QUAC type were identified. SLAC1/SLAH3 and QUAC1 are expressed in guard cells and mediate Slow- and Rapid-type anion currents, respectively, that are involved in volume and turgor regulation. Anion channels in guard cells and other plant cells are key targets within often complex signaling networks. Here, the present knowledge is reviewed for the plant ion channel biology. Special emphasis is drawn to the molecular mechanisms of channel regulation, in the context of model systems and in the light of evolution.

  10. 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

  11. 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.

  12. 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

  13. Estimating reservoir permeability from gravity current modeling of CO2 flow at Sleipner storage project, North Sea

    Science.gov (United States)

    Cowton, L. R.; Neufeld, J. A.; Bickle, M.; White, N.; White, J.; Chadwick, A.

    2017-12-01

    Vertically-integrated gravity current models enable computationally efficient simulations of CO2 flow in sub-surface reservoirs. These simulations can be used to investigate the properties of reservoirs by minimizing differences between observed and modeled CO2 distributions. At the Sleipner project, about 1 Mt yr-1 of supercritical CO2 is injected at a depth of 1 km into a pristine saline aquifer with a thick shale caprock. Analysis of time-lapse seismic reflection surveys shows that CO2 is distributed within 9 discrete layers. The trapping mechanism comprises a stacked series of 1 m thick, impermeable shale horizons that are spaced at 30 m intervals through the reservoir. Within the stratigraphically highest reservoir layer, Layer 9, a submarine channel deposit has been mapped on the pre-injection seismic survey. Detailed measurements of the three-dimensional CO2 distribution within Layer 9 have been made using seven time-lapse surveys, providing a useful benchmark against which numerical flow simulations can be tested. Previous simulations have, in general, been largely unsuccessful in matching the migration rate of CO2 in this layer. Here, CO2 flow within Layer 9 is modeled as a vertically-integrated gravity current that spreads beneath a structurally complex caprock using a two-dimensional grid, considerably increasing computational efficiency compared to conventional three-dimensional simulators. This flow model is inverted to find the optimal reservoir permeability in Layer 9 by minimizing the difference between observed and predicted distributions of CO2 as a function of space and time. A three parameter inverse model, comprising reservoir permeability, channel permeability and channel width, is investigated by grid search. The best-fitting reservoir permeability is 3 Darcys, which is consistent with measurements made on core material from the reservoir. Best-fitting channel permeability is 26 Darcys. Finally, the ability of this simplified numerical model

  14. 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.

  15. 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)

  16. 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

  17. Compound Wiretap Channels

    Directory of Open Access Journals (Sweden)

    Shlomo Shamai (Shitz

    2009-01-01

    Full Text Available This paper considers the compound wiretap channel, which generalizes Wyner's wiretap model to allow the channels to the (legitimate receiver and to the eavesdropper to take a number of possible states. No matter which states occur, the transmitter guarantees that the receiver decodes its message and that the eavesdropper is kept in full ignorance about the message. The compound wiretap channel can also be viewed as a multicast channel with multiple eavesdroppers, in which the transmitter sends information to all receivers and keeps the information secret from all eavesdroppers. For the discrete memoryless channel, lower and upper bounds on the secrecy capacity are derived. The secrecy capacity is established for the degraded channel and the semideterministic channel with one receiver. The parallel Gaussian channel is further studied. The secrecy capacity and the secrecy degree of freedom (s.d.o.f. are derived for the degraded case with one receiver. Schemes to achieve the s.d.o.f. for the case with two receivers and two eavesdroppers are constructed to demonstrate the necessity of a prefix channel in encoder design. Finally, the multi-antenna (i.e., MIMO compound wiretap channel is studied. The secrecy capacity is established for the degraded case and an achievable s.d.o.f. is given for the general case.

  18. Compound Wiretap Channels

    Directory of Open Access Journals (Sweden)

    Kramer Gerhard

    2009-01-01

    Full Text Available Abstract This paper considers the compound wiretap channel, which generalizes Wyner's wiretap model to allow the channels to the (legitimate receiver and to the eavesdropper to take a number of possible states. No matter which states occur, the transmitter guarantees that the receiver decodes its message and that the eavesdropper is kept in full ignorance about the message. The compound wiretap channel can also be viewed as a multicast channel with multiple eavesdroppers, in which the transmitter sends information to all receivers and keeps the information secret from all eavesdroppers. For the discrete memoryless channel, lower and upper bounds on the secrecy capacity are derived. The secrecy capacity is established for the degraded channel and the semideterministic channel with one receiver. The parallel Gaussian channel is further studied. The secrecy capacity and the secrecy degree of freedom ( are derived for the degraded case with one receiver. Schemes to achieve the for the case with two receivers and two eavesdroppers are constructed to demonstrate the necessity of a prefix channel in encoder design. Finally, the multi-antenna (i.e., MIMO compound wiretap channel is studied. The secrecy capacity is established for the degraded case and an achievable is given for the general case.

  19. ATP Release Channels

    Directory of Open Access Journals (Sweden)

    Akiyuki Taruno

    2018-03-01

    Full Text Available Adenosine triphosphate (ATP has been well established as an important extracellular ligand of autocrine signaling, intercellular communication, and neurotransmission with numerous physiological and pathophysiological roles. In addition to the classical exocytosis, non-vesicular mechanisms of cellular ATP release have been demonstrated in many cell types. Although large and negatively charged ATP molecules cannot diffuse across the lipid bilayer of the plasma membrane, conductive ATP release from the cytosol into the extracellular space is possible through ATP-permeable channels. Such channels must possess two minimum qualifications for ATP permeation: anion permeability and a large ion-conducting pore. Currently, five groups of channels are acknowledged as ATP-release channels: connexin hemichannels, pannexin 1, calcium homeostasis modulator 1 (CALHM1, volume-regulated anion channels (VRACs, also known as volume-sensitive outwardly rectifying (VSOR anion channels, and maxi-anion channels (MACs. Recently, major breakthroughs have been made in the field by molecular identification of CALHM1 as the action potential-dependent ATP-release channel in taste bud cells, LRRC8s as components of VRACs, and SLCO2A1 as a core subunit of MACs. Here, the function and physiological roles of these five groups of ATP-release channels are summarized, along with a discussion on the future implications of understanding these channels.

  20. Analysis and application of classification methods of complex carbonate reservoirs

    Science.gov (United States)

    Li, Xiongyan; Qin, Ruibao; Ping, Haitao; Wei, Dan; Liu, Xiaomei

    2018-06-01

    There are abundant carbonate reservoirs from the Cenozoic to Mesozoic era in the Middle East. Due to variation in sedimentary environment and diagenetic process of carbonate reservoirs, several porosity types coexist in carbonate reservoirs. As a result, because of the complex lithologies and pore types as well as the impact of microfractures, the pore structure is very complicated. Therefore, it is difficult to accurately calculate the reservoir parameters. In order to accurately evaluate carbonate reservoirs, based on the pore structure evaluation of carbonate reservoirs, the classification methods of carbonate reservoirs are analyzed based on capillary pressure curves and flow units. Based on the capillary pressure curves, although the carbonate reservoirs can be classified, the relationship between porosity and permeability after classification is not ideal. On the basis of the flow units, the high-precision functional relationship between porosity and permeability after classification can be established. Therefore, the carbonate reservoirs can be quantitatively evaluated based on the classification of flow units. In the dolomite reservoirs, the average absolute error of calculated permeability decreases from 15.13 to 7.44 mD. Similarly, the average absolute error of calculated permeability of limestone reservoirs is reduced from 20.33 to 7.37 mD. Only by accurately characterizing pore structures and classifying reservoir types, reservoir parameters could be calculated accurately. Therefore, characterizing pore structures and classifying reservoir types are very important to accurate evaluation of complex carbonate reservoirs in the Middle East.

  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. 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

  3. 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.

  4. 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.

  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. 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.

  7. 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.

  8. 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.

  9. Rapid reservoir erosion, hyperconcentrated flow, and downstream deposition triggered by breaching of 38 m tall Condit Dam, White Salmon River, Washington

    Science.gov (United States)

    Wilcox, Andrew C.; O'Connor, James E.; Major, Jon J.

    2014-01-01

    Condit Dam on the White Salmon River, Washington, a 38 m high dam impounding a large volume (1.8 million m3) of fine-grained sediment (60% sand, 35% silt and clay, and 5% gravel), was rapidly breached in October 2011. This unique dam decommissioning produced dramatic upstream and downstream geomorphic responses in the hours and weeks following breaching. Blasting a 5 m wide hole into the base of the dam resulted in rapid reservoir drawdown, abruptly releasing ~1.6 million m3 of reservoir water, exposing reservoir sediment to erosion, and triggering mass failures of the thickly accumulated reservoir sediment. Within 90 min of breaching, the reservoir's water and ~10% of its sediment had evacuated. At a gauging station 2.3 km downstream, flow increased briefly by 400 m3 s−1during passage of the initial pulse of released reservoir water, followed by a highly concentrated flow phase—up to 32% sediment by volume—as landslide-generated slurries from the reservoir moved downstream. This hyperconcentrated flow, analogous to those following volcanic eruptions or large landslides, draped the downstream river with predominantly fine sand. During the ensuing weeks, suspended-sediment concentration declined and sand and gravel bed load derived from continued reservoir erosion aggraded the channel by >1 m at the gauging station, after which the river incised back to near its initial elevation at this site. Within 15 weeks after breaching, over 1 million m3 of suspended load is estimated to have passed the gauging station, consistent with estimates that >60% of the reservoir's sediment had eroded. This dam removal highlights the influence of interactions among reservoir erosion processes, sediment composition, and style of decommissioning on rate of reservoir erosion and consequent downstream behavior of released sediment.

  10. 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

  11. Volume Regulated Channels

    DEFF Research Database (Denmark)

    Klausen, Thomas Kjær

    of volume perturbations evolution have developed system of channels and transporters to tightly control volume homeostasis. In the past decades evidence has been mounting, that the importance of these volume regulated channels and transporters are not restricted to the defense of cellular volume...... 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......- serves a multitude of functions in the mammalian cell, regulating the membrane potential (Em), cell volume, protein activity and the driving force for facilitated transporters giving Cl- and Cl- channels a major potential of regulating cellular function. These functions include control of the cell cycle...

  12. 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.

  13. 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.

  14. 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

  15. Nuclear reactor coolant channels

    International Nuclear Information System (INIS)

    Macbeth, R.V.

    1978-01-01

    Reference is made to coolant channels for pressurised water and boiling water reactors and the arrangement described aims to improve heat transfer between the fuel rods and the coolant. Baffle means extending axially within the channel are provided and disposed relative to the fuel rods so as to restrict flow oscillations occurring within the coolant from being propagated transversely to the axis of the channel. (UK)

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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......-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...

  1. Calcium Channel Blockers

    Science.gov (United States)

    ... Certain calcium channel blockers interact with grapefruit products. Kaplan NM, et al. Treatment of hypertension: Drug therapy. In: Kaplan's Clinical Hypertension. 11th ed. Philadelphia, Pa.: Wolters Kluwer ...

  2. 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.)

  3. 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

  4. The Application of a Multi-Beam Echo-Sounder in the Analysis of the Sedimentation Situation of a Large Reservoir after an Earthquake

    Directory of Open Access Journals (Sweden)

    Zhong-Luan Yan

    2018-04-01

    Full Text Available The Wenchuan Earthquake took place in the upper reach catchment of the Min River. It resulted in large amounts of loose materials gathering in the river channel, leading to changes in the sediment transport system in this area. The Zipingpu Reservoir is the last and the largest reservoir located in the upper reach of the Min River. It is near the epicenter and receives sediment from upstream. This paper puts forward a study on the reservoir sedimentation and storage capacity of the Zipingpu Reservoir, employing a multi-beam echo-sounder system in December 2012. Then, the data were merged with digital line graphics and shuttle radar topography mission data in ArcGIS to build a digital elevation model and triangulate the irregular network of Zipingpu Reservoir. Via the analysis of the bathymetric data, the results show the following: (1 The main channels of the reservoir gradually aggrade to a flat bottom from the deep-cutting valley. Sedimentation forms a reach with a W-shaped longitudinal thalweg profile and an almost zero slope reach in the upstream section of the reservoir due to the natural barrier induced by a landslide; (2 The loss ratios of the wetted cross-section surface are higher than 10% in the upstream section of the reservoir and higher than 40% in the natural barrier area; (3 Comparing the surveyed area storage capacity of December 2012 with March 2008, the Zipingpu Reservoir has lost 15.28% of its capacity at the dead storage water level and 10.49% of its capacity at the flood limit water level.

  5. Operational trade-offs in reservoir control

    Science.gov (United States)

    Georgakakos, Aris P.

    1993-11-01

    Reservoir operation decisions require constant reevaluation in the face of conflicting objectives, varying hydrologic conditions, and frequent operational policy changes. Optimality is a relative concept very much dependent on the circumstances under which a decision is made. More than anything else, reservoir management authorities need the means to assess the impacts of various operational options. It is their responsibility to define what is desirable after a thorough evaluation of the existing circumstances. This article presents a model designed to generate operational trade-offs common among reservoir systems. The model avoids an all-encompassing problem formulation and distinguishes three operational modes (levels) corresponding to normal, drought, and flood operations. Each level addresses only relevant system elements and uses a static and a dynamic control module to optimize turbine performance within each planning period and temporally. The model is used for planning the operation of the Savannah River System.

  6. Prediction of reservoir compaction and surface subsidence

    Energy Technology Data Exchange (ETDEWEB)

    De Waal, J.A.; Smits, R.M.M.

    1988-06-01

    A new loading-rate-dependent compaction model for unconsolidated clastic reservoirs is presented that considerably improves the accuracy of predicting reservoir rock compaction and surface subsidence resulting from pressure depletion in oil and gas fields. The model has been developed on the basis of extensive laboratory studies and can be derived from a theory relating compaction to time-dependent intergranular friction. The procedure for calculating reservoir compaction from laboratory measurements with the new model is outlined. Both field and laboratory compaction behaviors appear to be described by one single normalized, nonlinear compaction curve. With the new model, the large discrepancies usually observed between predictions based on linear compaction models and actual (nonlinear) field behavior can be explained.

  7. Reservoir Sedimentation: Impact, Extent, and Mitigation

    Science.gov (United States)

    Hadley, Richard F.

    Storage reservoirs play an important role in water resources development throughout the world. The one problem with reservoirs that is universal is the continual reduction in usable capacity caused by siltation. This book reviews the world picture of erosion and sediment yield, the large variations that exist, and the physical phenomena related to reservoir siltation. The book is in the Technical Paper series of The World Bank (Technical Paper 71) and is not a formal publication. Rather, it is intended to be circulated to encourage discussion and comment and to communicate results quickly. The book is reproduced from typescript, but this does not detract from the value of the contents as a useful text for hydrologrsts, engineers, and soil conservationists in developing countries.

  8. 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

  9. Frameworks for amending reservoir water management

    Science.gov (United States)

    Mower, Ethan; Miranda, Leandro E.

    2013-01-01

    Managing water storage and withdrawals in many reservoirs requires establishing seasonal targets for water levels (i.e., rule curves) that are influenced by regional precipitation and diverse water demands. Rule curves are established as an attempt to balance various water needs such as flood control, irrigation, and environmental benefits such as fish and wildlife management. The processes and challenges associated with amending rule curves to balance multiuse needs are complicated and mostly unfamiliar to non-US Army Corps of Engineers (USACE) natural resource managers and to the public. To inform natural resource managers and the public we describe the policies and process involved in amending rule curves in USACE reservoirs, including 3 frameworks: a general investigation, a continuing authority program, and the water control plan. Our review suggests that water management in reservoirs can be amended, but generally a multitude of constraints and competing demands must be addressed before such a change can be realized.

  10. 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...

  11. 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

  12. 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.

  13. 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...

  14. 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....

  15. HIV-1 Reservoir Association with Immune Activation

    Directory of Open Access Journals (Sweden)

    Alejandro Vallejo

    2015-09-01

    Full Text Available In this issue of EBioMedicine, Ruggiero and colleagues describe immune activation biomarkers associated with the size of the HIV reservoir in a carefully designed cross-sectional study. The cohort consists of a homogeneous sample of HIV-1-infected patients with long-term plasma HIV-1 RNA suppression under antiretroviral treatment (ART. It is crucial to explore the potential utility of biomarkers that are easier (less labor intensive, less expensive to measure than integrated HIV DNA load, in order to quickly and accurately quantify cellular reservoirs of HIV.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Rock Mass Classification of Karstic Terrain in the Reservoir Slopes of Tekeze Hydropower Project

    Science.gov (United States)

    Hailemariam Gugsa, Trufat; Schneider, Jean Friedrich

    2010-05-01

    Hydropower reservoirs in deep gorges usually experience slope failures and mass movements. History also showed that some of these projects suffered severe landslides, which left lots of victims and enormous economic loss. Thus, it became vital to make substantial slope stability studies in such reservoirs to ensure safe project development. This study also presents a regional scale instability assessment of the Tekeze Hydropower reservoir slopes. Tekeze hydropower project is a newly constructed double arch dam that completed in August 2009. It is developed on Tekeze River, tributary of Blue Nile River that runs across the northern highlands of Ethiopia. It cuts a savage gorge 2000m deep, the deepest canyon in Africa. The dam is the highest dam in Ethiopia at 188m, 10 m higher than China's Three Gorges Dam. It is being developed by Chinese company at a cost of US350M. The reservoir is designed at 1140 m elevation, as retention level to store more than 9000 million m3 volume of water that covers an area of 150 km2, mainly in channel filling form. In this study, generation of digital elevation model from ASTER satellite imagery and surface field investigation is initially considered for further image processing and terrain parameters' analyses. Digitally processed multi spectral ASTER ortho-images drape over the DEM are used to have different three dimensional perspective views in interpreting lithological, structural and geomorphological features, which are later verified by field mapping. Terrain slopes are also delineated from the relief scene. A GIS database is ultimately developed to facilitate the delineation of geotechnical units for slope rock mass classification. Accordingly, 83 geotechnical units are delineated and, within them, 240 measurement points are established to quantify in-situ geotechnical parameters. Due to geotechnical uncertainties, four classification systems; namely geomorphic rock mass strength classification (RMS), slope mass rating (SMR

  2. 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.

  3. 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

  4. 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...

  5. 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 .

  6. Anemia crônica e glomerulopatia secundárias à Doença de Depósito das Cadeias Leves Chronic anemia and glomerulopathy secondary to Light-chain Deposition Disease

    Directory of Open Access Journals (Sweden)

    Ítala P. Silveira

    2004-01-01

    Full Text Available Os autores relatam o caso de uma paciente do sexo feminino, 65 anos de idade, internada com anemia de longa evolução que se associou posteriormente a uma glomerulopatia manifestada por proteinúria, cilindrúria e perda de função renal. As cadeias leves no plasma e na urina estavam elevadas, sobretudo a fração kappa e uma biópsia renal estudada por imunofluorescência e microscopia eletrônica confirmou o diagnóstico de Doença de Depósito das Cadeias Leves. A nefropatia de cadeia leve ocorre pela superprodução de cadeia leve de imunoglobulina produzida por linfócitos B com deposição nas membranas tubulares e no glomérulo.The authors present a case of a 65-year-old female patient, with chronic anemia associated with glomerulopathy manifested as proteinuria, cylindruria and renal failure. There were high serum and urinary levels of light chains and the diagnosis was performed by renal biopsy, examined using immunofluorescence and by electron microscopy that showed light chain paraproteins. Nephropathy of light-chain deposition disease occurs due to an over-production of light chains from immunoglobulins produced by B lymphocytes with a deposit in tubular and glomerular membranes.

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. Ephemeral-fluvial sediments as potential hydrocarbon reservoirs. Vol. 1: Sedimentology

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, K.S.

    1994-12-31

    Although reservoirs formed from ephemeral-fluvial sandstones have previously been considered relatively simple, unresolved problems of sandbody correlation and production anomalies demonstrate the need for improved understanding of their internal complexity. Outcropping ephemeral-fluvial systems have been studied in order to determine the main features and processes occurring in sand-rich ephemeral systems and to identify which features will be of importance in a hydrocarbon reservoir. The Lower Jurassic Upper Moenave and Kayenta Formations of south-eastern Utah and northern Arizona comprise series of stacked, sand-dominated sheet-like palaeochannels suggestive of low sinuosity, braided systems. Low subsidence rates and rapid lateral migration rates enabled channels to significantly modify their widths during high discharge. (author)

  12. Omni channel fashion shopping

    NARCIS (Netherlands)

    Kemperman, A.D.A.M.; van Delft, L.; Borgers, A.W.J.; Pantano, E.

    2015-01-01

    This chapter gives insight into consumers' online and offline fashion shopping behavior, consumers' omni-channel usage during the shopping process, and consumer fashion shopper segments. Based on a literature review, omni-channel shopping behavior during the shopping process was operationalized.

  13. 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.

  14. Channel electron multipliers

    International Nuclear Information System (INIS)

    Seidman, A.; Avrahami, Z.; Sheinfux, B.; Grinberg, J.

    1976-01-01

    A channel electron multiplier is described having a tubular wall coated with a secondary-electron emitting material and including an electric field for accelerating the electrons, the electric field comprising a plurality of low-resistive conductive rings each alternating with a high-resistive insulating ring. The thickness of the low-resistive rings is many times larger than that of the high-resistive rings, being in the order of tens of microns for the low-resistive rings and at least one order of magnitude lower for the high-resistive rings; and the diameter of the channel tubular walls is also many times larger than the thickness of the high-resistive rings. Both single-channel and multiple-channel electron multipliers are described. A very important advantage, particularly in making multiple-channel multipliers, is the simplicity of the procedure that may be used in constructing such multipliers. Other operational advantages are described

  15. Cardiac potassium channel subtypes

    DEFF Research Database (Denmark)

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

    2014-01-01

    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...... drive the late repolarization of the ventricle with some redundancy, and in atria this repolarization reserve is supplemented by the fairly atrial-specific KV1.5, Kir3, KCa, and K2P channels. The role of the latter two subtypes in atria is currently being clarified, and several findings indicate...... 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...

  16. 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......(-) channels or as regulators of other apoptotic Cl(-) channels, such as LRRC8. CFTR has been known for its proapoptotic effects for some time, and this effect may be based on glutathione release from the cell and increase in cytosolic reactive oxygen species (ROS). Although we find that CFTR is activated...

  17. CHANNEL ESTIMATION TECHNIQUE

    DEFF Research Database (Denmark)

    2015-01-01

    A method includes determining a sequence of first coefficient estimates of a communication channel based on a sequence of pilots arranged according to a known pilot pattern and based on a receive signal, wherein the receive signal is based on the sequence of pilots transmitted over the communicat......A method includes determining a sequence of first coefficient estimates of a communication channel based on a sequence of pilots arranged according to a known pilot pattern and based on a receive signal, wherein the receive signal is based on the sequence of pilots transmitted over...... 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...... filter characteristics of at least one known transceiver filter arranged in the communication channel....

  18. 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

  19. 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.

  20. 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.

  1. 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.

    of the central part of the Indo- Gangetic Plain just north of the Tropic of Cancer. The eighth – the Bhakra-Nangal Dam is built over the Sutlej River at the foothills of the Himalayas. The reservoirs of these dams vary greatly in size from very small systems...

  2. 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

  3. 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

  4. Landscape runoff, precipitation variation and reservoir limnology

    OpenAIRE

    Geraldes, Ana Maria

    2010-01-01

    Landscape runoff potential impact on reservoir limnology was indirectly evaluated by assessing the effect of precipitation variation on several water quality parameters, on Anabaena (Cyanophyta) and crustacean zooplankton abundances. The obtained results showed that total phosphorus increased with strong precipitation events whereas water transparency presented an opposite trend. Wet periods followed by long dry periods favored Anabaena dominance, which induced a...

  5. 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.

  6. 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.

  7. Accouting for Greenhouse Gas Emissions from Reservoirs

    Science.gov (United States)

    Beaulieu, J. J.; Deemer, B. R.; Harrison, J. A.; Nietch, C. T.; Waldo, S.

    2016-12-01

    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 emissions linked to the National Lakes Assessment.

  8. 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.

  9. 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

  10. 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...

  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. Exponential rate of convergence in current reservoirs

    OpenAIRE

    De Masi, Anna; Presutti, Errico; Tsagkarogiannis, Dimitrios; Vares, Maria Eulalia

    2015-01-01

    In this paper, we consider a family of interacting particle systems on $[-N,N]$ that arises as a natural model for current reservoirs and Fick's law. We study the exponential rate of convergence to the stationary measure, which we prove to be of the order $N^{-2}$.

  13. Parallel Numerical Simulations of Water Reservoirs

    Science.gov (United States)

    Torres, Pedro; Mangiavacchi, Norberto

    2010-11-01

    The study of the water flow and scalar transport in water reservoirs is important for the determination of the water quality during the initial stages of the reservoir filling and during the life of the reservoir. For this scope, a parallel 2D finite element code for solving the incompressible Navier-Stokes equations coupled with scalar transport was implemented using the message-passing programming model, in order to perform simulations of hidropower water reservoirs in a computer cluster environment. The spatial discretization is based on the MINI element that satisfies the Babuska-Brezzi (BB) condition, which provides sufficient conditions for a stable mixed formulation. All the distributed data structures needed in the different stages of the code, such as preprocessing, solving and post processing, were implemented using the PETSc library. The resulting linear systems for the velocity and the pressure fields were solved using the projection method, implemented by an approximate block LU factorization. In order to increase the parallel performance in the solution of the linear systems, we employ the static condensation method for solving the intermediate velocity at vertex and centroid nodes separately. We compare performance results of the static condensation method with the approach of solving the complete system. In our tests the static condensation method shows better performance for large problems, at the cost of an increased memory usage. Performance results for other intensive parts of the code in a computer cluster are also presented.

  14. Studies of Reservoir Hosts for Marburg virus

    DEFF Research Database (Denmark)

    Swanepoel, Robert; Smit, Sheilagh B; Rollin, Pierre E

    2007-01-01

    To determine reservoir hosts for Marburg virus (MARV), we examined the fauna of a mine in northeastern Democratic Republic of the Congo. The mine was associated with a protracted outbreak of Marburg hemorrhagic fever during 1998-2000. We found MARV nucleic acid in 12 bats, comprising 3.0%-3.6% of...

  15. 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

  16. 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.

  17. 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.

  18. CANDU channel flow verification

    International Nuclear Information System (INIS)

    Mazalu, N.; Negut, Gh.

    1997-01-01

    The purpose of this evaluation was to obtain accurate information on each channel flow that enables us to assess precisely the level of reactor thermal power and, for reasons of safety, to establish which channel is boiling. In order to assess the channel flow parameters, computer simulations were done with the NUCIRC code and the results were checked by measurements. The complete channel flow measurements were made in the zero power cold condition. In hot conditions there were made flow measurements using the Shut Down System 1 (SDS 1) flow devices from 0.1 % F.P. up to 100 % F.P. The NUCIRC prediction for CANDU channel flows and the measurements by Ultrasonic Flow Meter at zero power cold conditions and SDS 1 flow channel measurements at different reactor power levels showed an acceptable agreement. The 100 % F.P. average errors for channel flow of R, shows that suitable NUCIRC flow assessment can be made. So, it can be done a fair prediction of the reactor power distribution. NUCIRC can predict accurately the onset of boiling and helps to warn at the possible power instabilities at high powers or it can detect the flow blockages. The thermal hydraulic analyst has in NUCIRC a suitable tool to do accurate predictions for the thermal hydraulic parameters for different steady state power levels which subsequently leads to an optimal CANDU reactor operation. (authors)

  19. 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....

  20. Evaluation of Gaussian approximations for data assimilation in reservoir models

    KAUST Repository

    Iglesias, Marco A.; Law, Kody J H; Stuart, Andrew M.

    2013-01-01

    is fundamental for the optimal management of reservoirs. Unfortunately, due to the large-scale highly nonlinear properties of standard reservoir models, characterizing the posterior is computationally prohibitive. Instead, more affordable ad hoc techniques, based

  1. 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

  2. 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.

  3. Reconfigurable virtual electrowetting channels.

    Science.gov (United States)

    Banerjee, Ananda; Kreit, Eric; Liu, Yuguang; Heikenfeld, Jason; Papautsky, Ian

    2012-02-21

    Lab-on-a-chip systems rely on several microfluidic paradigms. The first uses a fixed layout of continuous microfluidic channels. Such lab-on-a-chip systems are almost always application specific and far from a true "laboratory." The second involves electrowetting droplet movement (digital microfluidics), and allows two-dimensional computer control of fluidic transport and mixing. The merging of the two paradigms in the form of programmable electrowetting channels takes advantage of both the "continuous" functionality of rigid channels based on which a large number of applications have been developed to date and the "programmable" functionality of digital microfluidics that permits electrical control of on-chip functions. In this work, we demonstrate for the first time programmable formation of virtual microfluidic channels and their continuous operation with pressure driven flows using an electrowetting platform. Experimental, theoretical, and numerical analyses of virtual channel formation with biologically relevant electrolyte solutions and electrically-programmable reconfiguration are presented. We demonstrate that the "wall-less" virtual channels can be formed reliably and rapidly, with propagation rates of 3.5-3.8 mm s(-1). Pressure driven transport in these virtual channels at flow rates up to 100 μL min(-1) is achievable without distortion of the channel shape. We further demonstrate that these virtual channels can be switched on-demand between multiple inputs and outputs. Ultimately, we envision a platform that would provide rapid prototyping of microfluidic concepts and would be capable of a vast library of functions and benefitting applications from clinical diagnostics in resource-limited environments to rapid system prototyping to high throughput pharmaceutical applications.

  4. Effects of Reservoirs Releases on Tailwater Ecology: A Literature Review.

    Science.gov (United States)

    1981-09-01

    intlix i n totil woters exhibi t.ing these types of flutua, ~is(Tror sky ain. iecr 7 P1cc ot e r 190. Plec ~ -trosre us ri 11 not found in tai Iwaters...Coldwater seis( plec ( ptez--ns anti trout.) may be elimi nated by temeratures exceodiif ig hi r t 3)1 aaice leve~ls. Ilevatett temperatu~res -ilso may allow

  5. Increasing Waterflood Reserves in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, D.; Koerner, R.; Moos D.; Nguyen, J.; Phillips, C.; Tagbor, K.; Walker, S.

    1999-04-05

    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.

  6. 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

  7. 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.

  8. Channel follower leakage restrictor

    International Nuclear Information System (INIS)

    Williamson, H.E.; Smith, B.A.

    1977-01-01

    An improved means is provided to control coolant leakage between the flow channel and the lower tie plate of a nuclear fuel assembly. The means includes an opening in the lower tie plate and a movable element adjacent thereto. The coolant pressure within the tie plate biases the movable means toward the inner surface of the surrounding flow channel to compensate for any movement of the flow channel away from the lower tie plate to thereby control the leakage of coolant flow from the fuel assemblies to the spaces among the fuel assemblies of the core. 9 figures

  9. State of the art of reservoir sedimentation management in Spain

    OpenAIRE

    Avendaño Salas, Cándido; Sanz Montero, Esther; Cobo Rayán, Rafael

    2000-01-01

    Part of the total reservoir storage capacity in Spain (56 km3) is lost due to sedimentation processes taking place. Surveys carried out in 121 reservoirs indicate that 6% of them have undergone a capacity reduction of over 50%. However, most of them (81%) are characterised by a reservoir capacity loss below 20%. The most frequent methods used to control reservoir sedimentation in Spain fall into one of the following groups: reduction of sediment yield through basin management and removal of t...

  10. 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)

  11. Reservoir management under consideration of stratification and hydraulic phenomena

    OpenAIRE

    Nandalal, K.D.W.

    1995-01-01


    Reservoirs are the most important components in a water resources system. They are used to store water to extend its temporal availability. The physical, chemical and biological characteristics of water change when impounded in reservoirs. This implies the possibility of using reservoirs for the control of the quality of water besides merely satisfying the quantity requirement. This study presents several techniques formulated to manage a reservoir when both quantity and quality of...

  12. 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.

  13. 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

  14. 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

  15. Mathematical and field analysis of longitudinal reservoir infill

    Science.gov (United States)

    Ke, W. T.; Capart, H.

    2016-12-01

    In reservoirs, severe problems are caused by infilled sediment deposits. In long term, the sediment accumulation reduces the capacity of reservoir storage and flood control benefits. In the short term, the sediment deposits influence the intakes of water-supply and hydroelectricity generation. For the management of reservoir, it is important to understand the deposition process and then to predict the sedimentation in reservoir. To investigate the behaviors of sediment deposits, we propose a one-dimensional simplified theory derived by the Exner equation to predict the longitudinal sedimentation distribution in idealized reservoirs. The theory models the reservoir infill geomorphic actions for three scenarios: delta progradation, near-dam bottom deposition, and final infill. These yield three kinds of self-similar analytical solutions for the reservoir bed profiles, under different boundary conditions. Three analytical solutions are composed by error function, complementary error function, and imaginary error function, respectively. The theory is also computed by finite volume method to test the analytical solutions. The theoretical and numerical predictions are in good agreement with one-dimensional small-scale laboratory experiment. As the theory is simple to apply with analytical solutions and numerical computation, we propose some applications to simulate the long-profile evolution of field reservoirs and focus on the infill sediment deposit volume resulting the uplift of near-dam bottom elevation. These field reservoirs introduced here are Wushe Reservoir, Tsengwen Reservoir, Mudan Reservoir in Taiwan, Lago Dos Bocas in Puerto Rico, and Sakuma Dam in Japan.

  16. 33 CFR 110.77 - Amistad Reservoir, Tex.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Amistad Reservoir, Tex. 110.77... ANCHORAGE REGULATIONS Special Anchorage Areas § 110.77 Amistad Reservoir, Tex. (a) Diablo East, Tex. That portion of the Amistad Reservoir enclosed by a line connecting the following points, excluding a 300-foot...

  17. Analysis of Fluvial Sediment Discharges into Kubanni Reservoir ...

    African Journals Online (AJOL)

    The sediment discharges into the Kubanni Reservoir (KR) has been measured and analysed in this study. The predominant sandy-clay sediment in the reservoir has an estimated total sediment load of 20,387,000 kg/year. The depth and area coverage of the reservoir was surveyed using a defined distributed grid line ...

  18. Reservoir site evaluation through routing | Ogunlela | Journal of ...

    African Journals Online (AJOL)

    ... m3/s, and a relative attenuation of 41.10%. Also; the reservoir would not be overtopped since the 99.54 m water elevation for the 25-yr, 24-hr storm was below the reservoir embankment top elevation. Keywords:Reservoir routing. Journal of Modeling, Design and Management of Engineering Systems Vol. 3 (1) 2005: pp.

  19. Reservoir management under consideration of stratification and hydraulic phenomena

    NARCIS (Netherlands)

    Nandalal, K.D.W.

    1995-01-01


    Reservoirs are the most important components in a water resources system. They are used to store water to extend its temporal availability. The physical, chemical and biological characteristics of water change when impounded in reservoirs. This implies the possibility of using reservoirs

  20. Third workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P. (eds.)

    1977-12-15

    The Third Workshop on Geothermal Reservoir Engineering convened at Stanford University on December 14, 1977, with 104 attendees from six nations. In keeping with the recommendations expressed by the participants at the Second Workshop, the format of the Workshop was retained, with three days of technical sessions devoted to reservoir physics, well and reservoir testing, field development, and mathematical modeling of geothermal reservoirs. The program presented 33 technical papers, summaries of which are included in these Proceedings. Although the format of the Workshop has remained constant, it is clear from a perusal of the Table of Contents that considerable advances have occurred in all phases of geothermal reservoir engineering over the past three years. Greater understanding of reservoir physics and mathematical representations of vapor-dominated and liquid-dominated reservoirs are evident; new techniques for their analysis are being developed, and significant field data from a number of newer reservoirs are analyzed. The objectives of these workshops have been to bring together researchers active in the various physical and mathematical disciplines comprising the field of geothermal reservoir engineering, to give the participants a forum for review of progress and exchange of new ideas in this rapidly developing field, and to summarize the effective state of the art of geothermal reservoir engineering in a form readily useful to the many government and private agencies involved in the development of geothermal energy. To these objectives, the Third Workshop and these Proceedings have been successfully directed. Several important events in this field have occurred since the Second Workshop in December 1976. The first among these was the incorporation of the Energy Research and Development Administration (ERDA) into the newly formed Department of Energy (DOE) which continues as the leading Federal agency in geothermal reservoir engineering research. The Third

  1. Advanced Gas Hydrate Reservoir Modeling Using Rock Physics

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, Daniel

    2017-12-30

    Prospecting for high saturation gas hydrate deposits can be greatly aided with improved approaches to seismic interpretation and especially if sets of seismic attributes can be shown as diagnostic or direct hydrocarbon indicators for high saturation gas hydrates in sands that would be of most interest for gas hydrate production.

    A large 3D seismic data set in the deep water Eastern Gulf of Mexico was screened for gas hydrates using a set of techniques and seismic signatures that were developed and proven in the Central deepwater Gulf of Mexico in the DOE Gulf of Mexico Joint Industry Project JIP Leg II in 2009 and recently confirmed with coring in 2017.

    A large gas hydrate deposit is interpreted in the data where gas has migrated from one of the few deep seated faults plumbing the Jurassic hydrocarbon source into the gas hydrate stability zone. The gas hydrate deposit lies within a flat-lying within Pliocene Mississippi Fan channel that was deposited outboard in a deep abyssal environment. The uniform architecture of the channel aided the evaluation of a set of seismic attributes that relate to attenuation and thin-bed energy that could be diagnostic of gas hydrates. Frequency attributes derived from spectral decomposition also proved to be direct hydrocarbon indicators by pseudo-thickness that could be only be reconciled by substituting gas hydrate in the pore space. The study emphasizes that gas hydrate exploration and reservoir characterization benefits from a seismic thin bed approach.

  2. Many channel spectrum unfolding

    International Nuclear Information System (INIS)

    Najzer, M.; Glumac, B.; Pauko, M.

    1980-01-01

    The principle of the ITER unfolding code as used for the many channel spectrum unfolding is described. Its unfolding ability is tested on seven typical neutron spectra. The effect of the initial spectrum approximation upon the solution is discussed

  3. Channelized Streams in Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This draft dataset consists of all ditches or channelized pieces of stream that could be identified using three input datasets; namely the1:24,000 National...

  4. 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.

  5. 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.

  6. 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.

  7. TRP channels: an overview

    DEFF Research Database (Denmark)

    Pedersen, Stine Falsig; Owsianik, Grzegorz; Nilius, Bernd

    2005-01-01

    The TRP ("transient receptor potential") family of ion channels now comprises more than 30 cation channels, most of which are permeable for Ca2+, and some also for Mg2+. On the basis of sequence homology, the TRP family can be divided in seven main subfamilies: the TRPC ('Canonical') family......, the TRPV ('Vanilloid') family, the TRPM ('Melastatin') family, the TRPP ('Polycystin') family, the TRPML ('Mucolipin') family, the TRPA ('Ankyrin') family, and the TRPN ('NOMPC') family. The cloning and characterization of members of this cation channel family has exploded during recent years, leading...... to a plethora of data on the roles of TRPs in a variety of tissues and species, including mammals, insects, and yeast. The present review summarizes the most pertinent recent evidence regarding the structural and functional properties of TRP channels, focusing on the regulation and physiology of mammalian TRPs....

  8. The Missing Link: the Role of Floodplain Tie Channels in Connecting Off River Water Bodies to Lowland Rivers

    Science.gov (United States)

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

    2005-05-01

    Along lowland river systems across the globe the exchange of water, sediment, carbon, nutrients and biota between main stem rivers and off-river water bodies (ORWB) is facilitated by the presence of stable secondary channels referred to here as tie channels. Sixty five percent of the ORWB along the middle Fly River in Papua New Guinea connect to the river through such channels. A similar percentage of the 37 ORWB located between Baton Rouge and Memphis on the lower Mississippi River at one time were linked to the river by tie or batture (as they are locally known) channels. Levee construction and other alterations aimed at flood control or navigation on the Mississippi have left only a handful of lakes connected to the river, of these, most are heavily altered by dredging or other modifications. Tie channels were also once common along major tributaries to the Mississippi, such as the Red River. In the much less disturbed Alaskan environment, tie channels are still common, especially along Birch Creek and the Koyukuk and Black rivers. Our studies on the Mississippi River, in Alaska and in Papua New Guinea indicate that tie channels possess a common channel form that is stable and self-maintaining for hundreds to possibly a thousand years. Tie channels exhibit narrow width to depth ratios (~ 5.5) and consistently scale in cross-sectional dimensions to the size of the lake into which they flow. Variations in river and lake stage drive flow bi-directionally through tie channels. A local high or sill in the bed of tie channels controls the degree and duration of connection between the river and ORWB, with many lakes becoming isolated during periods of low stage. The life-span of a tie channel depends on the rate of sediment loading to the ORWB. Our research indicates that this rate directly corresponds to the sediment loading in the main stem river. Along the Fly River, for example, a 5 to 7 fold increase in the river sediment load has resulted increases of 6 to 17

  9. An Intelligent Systems Approach to Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Shahab D. Mohaghegh; Jaime Toro; Thomas H. Wilson; Emre Artun; Alejandro Sanchez; Sandeep Pyakurel

    2005-08-01

    Today, the major challenge in reservoir characterization is integrating data coming from different sources in varying scales, in order to obtain an accurate and high-resolution reservoir model. The role of seismic data in this integration is often limited to providing a structural model for the reservoir. Its relatively low resolution usually limits its further use. However, its areal coverage and availability suggest that it has the potential of providing valuable data for more detailed reservoir characterization studies through the process of seismic inversion. In this paper, a novel intelligent seismic inversion methodology is presented to achieve a desirable correlation between relatively low-frequency seismic signals, and the much higher frequency wireline-log data. Vertical seismic profile (VSP) is used as an intermediate step between the well logs and the surface seismic. A synthetic seismic model is developed by using real data and seismic interpretation. In the example presented here, the model represents the Atoka and Morrow formations, and the overlying Pennsylvanian sequence of the Buffalo Valley Field in New Mexico. Generalized regression neural network (GRNN) is used to build two independent correlation models between; (1) Surface seismic and VSP, (2) VSP and well logs. After generating virtual VSP's from the surface seismic, well logs are predicted by using the correlation between VSP and well logs. The values of the density log, which is a surrogate for reservoir porosity, are predicted for each seismic trace through the seismic line with a classification approach having a correlation coefficient of 0.81. The same methodology is then applied to real data taken from the Buffalo Valley Field, to predict inter-well gamma ray and neutron porosity logs through the seismic line of interest. The same procedure can be applied to a complete 3D seismic block to obtain 3D distributions of reservoir properties with less uncertainty than the geostatistical

  10. Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf Carbonate Reservoir

    International Nuclear Information System (INIS)

    Hickman, Scott T.; Justice James L.; Taylor, Archie R.

    1999-01-01

    The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs

  11. Authentication over Noisy Channels

    OpenAIRE

    Lai, Lifeng; Gamal, Hesham El; Poor, H. Vincent

    2008-01-01

    In this work, message authentication over noisy channels is studied. The model developed in this paper is the authentication theory counterpart of Wyner's wiretap channel model. Two types of opponent attacks, namely impersonation attacks and substitution attacks, are investigated for both single message and multiple message authentication scenarios. For each scenario, information theoretic lower and upper bounds on the opponent's success probability are derived. Remarkably, in both scenarios,...

  12. 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....

  13. Stream Channel Stability.

    Science.gov (United States)

    1981-04-01

    Cycles of wetting and drying are also t ,v itiue swelling and shrinkage of the soil. S 11ied blocks or peds of soil fabric ,,ks. id downslope soil creep ...hydrographs of water and sediment at the point in question. By feeding the output from the hydrology-transport model into the finite element model...the banks as undercut banks fail. Channel irregularities such as seepage zones, cattle crossings, overbank drainage, buried channels, organic deposits

  14. Channeling and dynamic chaos

    Energy Technology Data Exchange (ETDEWEB)

    Bolotin, IU L; Gonchar, V IU; Truten, V I; Shulga, N F

    1986-01-01

    It is shown that axial channeling of relativistic electrons can give rise to the effect of dynamic chaos which involves essentially chaotic motion of a particle in the channel. The conditions leading to the effect of dynamic chaos and the manifestations of this effect in physical processes associated with the passage of particles through a crystal are examined using a silicon crystal as an example. 7 references.

  15. Fort Cobb Reservoir Watershed, Oklahoma and Thika River Watershed, Kenya Twinning Pilot Project

    Science.gov (United States)

    Moriasi, D.; Steiner, J.; Arnold, J.; Allen, P.; Dunbar, J.; Shisanya, C.; Gathenya, J.; Nyaoro, J.; Sang, J.

    2007-12-01

    The Fort Cobb Reservoir Watershed (FCRW) (830 km2) is a watershed within the HELP Washita Basin, located in Caddo and Washita Counties, OK. It is also a benchmark watershed under USDA's Conservation Effects Assessment Project, a national project to quantify environmental effects of USDA and other conservation programs. Population in south-western Oklahoma, in which FCRW is located, is sparse and decreasing. Agricultural focuses on commodity production (beef, wheat, and row crops) with high costs and low margins. Surface and groundwater resources supply public, domestic, and irrigation water. Fort Cobb Reservoir and contributing stream segments are listed on the Oklahoma 303(d) list as not meeting water quality standards based on sedimentation, trophic level of the lake associated with phosphorus loads, and nitrogen in some stream segments in some seasons. Preliminary results from a rapid geomorphic assessment results indicated that unstable stream channels dominate the stream networks and make a significant but unknown contribution to suspended-sediment loadings. Impairment of the lake for municipal water supply, recreation, and fish and wildlife are important factors in local economies. The Thika River Watershed (TRW) (867 km2) is located in central Kenya. Population in TRW is high and increasing, which has led to a poor land-population ratio with population densities ranging from 250 people/km2 to over 500 people/km2. The poor land-population ratio has resulted in land sub-division, fragmentation, over- cultivation, overgrazing, and deforestation which have serious implications on soil erosion, which poses a threat to both agricultural production and downstream reservoirs. Agricultural focuses mainly on subsistence and some cash crops (dairy cattle, corn, beans, coffee, floriculture and pineapple) farming. Surface and groundwater resources supply domestic, public, and hydroelectric power generation water. Thika River supplies 80% of the water for the city of

  16. Modeling Reservoir-River Networks in Support of Optimizing Seasonal-Scale Reservoir Operations

    Science.gov (United States)

    Villa, D. L.; Lowry, T. S.; Bier, A.; Barco, J.; Sun, A.

    2011-12-01

    HydroSCOPE (Hydropower Seasonal Concurrent Optimization of Power and the Environment) is a seasonal time-scale tool for scenario analysis and optimization of reservoir-river networks. Developed in MATLAB, HydroSCOPE is an object-oriented model that simulates basin-scale dynamics with an objective of optimizing reservoir operations to maximize revenue from power generation, reliability in the water supply, environmental performance, and flood control. HydroSCOPE is part of a larger toolset that is being developed through a Department of Energy multi-laboratory project. This project's goal is to provide conventional hydropower decision makers with better information to execute their day-ahead and seasonal operations and planning activities by integrating water balance and operational dynamics across a wide range of spatial and temporal scales. This presentation details the modeling approach and functionality of HydroSCOPE. HydroSCOPE consists of a river-reservoir network model and an optimization routine. The river-reservoir network model simulates the heat and water balance of river-reservoir networks for time-scales up to one year. The optimization routine software, DAKOTA (Design Analysis Kit for Optimization and Terascale Applications - dakota.sandia.gov), is seamlessly linked to the network model and is used to optimize daily volumetric releases from the reservoirs to best meet a set of user-defined constraints, such as maximizing revenue while minimizing environmental violations. The network model uses 1-D approximations for both the reservoirs and river reaches and is able to account for surface and sediment heat exchange as well as ice dynamics for both models. The reservoir model also accounts for inflow, density, and withdrawal zone mixing, and diffusive heat exchange. Routing for the river reaches is accomplished using a modified Muskingum-Cunge approach that automatically calculates the internal timestep and sub-reach lengths to match the conditions of

  17. Geological modeling for methane hydrate reservoir characterization in the eastern Nankai Trough, offshore Japan

    Science.gov (United States)

    Tamaki, M.; Komatsu, Y.; Suzuki, K.; Takayama, T.; Fujii, T.

    2012-12-01

    The eastern Nankai trough, which is located offshore of central Japan, is considered as an attractive potential resource field of methane hydrates. Japan Oil, Gas and Metals National Corporation is planning to conduct a production test in early 2013 at the AT1 site in the north slope of Daini-Atsumi Knoll in the eastern Nankai Trough. The depositional environment of methane hydrate-bearing sediments around the production test site is a deep submarine-fan turbidite system, and it is considered that the reservoir properties should show lateral as well as vertical heterogeneity. Since the variations in the reservoir heterogeneity have an impact on the methane hydrate dissociation and gas production performance, precise geological models describing reservoir heterogeneity would be required for the evaluation of reservoir potentials. In preparation for the production test, 3 wells; two monitoring boreholes (AT1-MC and AT1-MT1) and a coring well (AT1-C), were newly acquired in 2012. In addition to a geotechnical hole drilling survey in 2011 (AT1-GT), totally log data from 2 wells and core data from 2 wells were obtained around the production test site. In this study, we conducted well correlations between AT1 and A1 wells drilled in 2003 and then, 3D geological models were updated including AT1 well data in order to refine hydrate reservoir characterization around the production test site. The results of the well correlations show that turbidite sand layers are characterized by good lateral continuity, and give significant information for the distribution morphology of sand-rich channel fills. We also reviewed previously conducted 3D geological models which consist of facies distributions and petrophysical properties distributions constructed from integration of 3D seismic data and a well data (A1 site) adopting a geostatistical approach. In order to test the practical validity of the previously generated models, cross-validation was conducted using AT1 well data. The

  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. IMPORTANCE OF SHALLOW AREAS OF THE UPPER PART OF THE KANIV RESERVOIR IN THE MAINTENANCE OF ITS ICHTHYOFAUNA

    Directory of Open Access Journals (Sweden)

    O. Gurbyk

    2014-09-01

    Full Text Available Purpose. Determination of the relative number of fish juveniles on biotopes of the upper part of the Kanev reservoir in the aspect of evaluation of these areas in general propagation of ichthyofauna. Methodology. The work is based on data of fish juvenile surveys conducted in the Kaniv reservoir during 2011—2013. Data collection and processing were performed according to generally accepted methods. Fish juveniles were caught using a beach seine made of mill gauze № 7, length 10 m, height 1 m. Relative number of fish juveniles on different sites has been calculated based on the areas of fish nursing biotopes under assumption of the constancy of catchability coefficients. Shannon-Weaver diversity index was used for comparing species diversity of the commercial ichthyofauna of different sites. Findings. The majority of the studied littoral sites of the upper part of the Kaniv reservoir were characterized by sufficiently high indices of biodiversity ― Shannon index values varied within 2,07—3,24 bit./ind. Twenty six species were recorded in the composition of the fish juvenile communities that was 80 % of total number of species in the reservoir. It was found that despite a decrease of the relative number of the juveniles of valuable commercial species compared to previous years, the upper part of the reservoir remains the major site for recruitment of commercial fish stock ― 70 % of bream (Abramis brama, tench (Tinca tinca, pike (Esox lucius, roach (Rutilus rutilus and wels (Vimba vimba of the Kaniv reservoir are reproduced here. Taking into account the especial value of the upper part in formation of the spawning fund of the reservoir, any hydroenhancement works here should be limited exclusively by navigable channel. Originality. For the first time we quantitatively evaluated (in spatial aspect the number of fish fauna recruitment in the Kanev reservoir under current state of spawning areas. Practical value. Results of the work will be

  20. Maqalika Reservoir: utilisation and sustainability of Maqalika Reservoir as a source of potable water supply for Maseru in Lesotho

    CSIR Research Space (South Africa)

    Letsie, M

    2008-07-01

    Full Text Available The storage of water in the Maqalika reservoir is gradually decreasing as sediment, carried by the natural catchment run-off, accumulates in the reservoir. Moreover, water pumped into the reservoir from the Caledon River (which is heavily sedimented...

  1. Modeling reservoir geomechanics using discrete element method : Application to reservoir monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Alassi, Haitham Tayseer

    2008-09-15

    Understanding reservoir geomechanical behavior is becoming more and more important for the petroleum industry. Reservoir compaction, which may result in surface subsidence and fault reactivation, occurs during reservoir depletion. Stress changes and possible fracture development inside and outside a depleting reservoir can be monitored using time-lapse (so-called '4D') seismic and/or passive seismic, and this can give valuable information about the conditions of a given reservoir during production. In this study we will focus on using the (particle-based) Discrete Element Method (DEM) to model reservoir geomechanical behavior during depletion and fluid injection. We show in this study that DEM can be used in modeling reservoir geomechanical behavior by comparing results obtained from DEM to those obtained from analytical solutions. The match of the displacement field between DEM and the analytical solution is good, however there is mismatch of the stress field which is related to the way stress is measured in DEM. A good match is however obtained by measuring the stress field carefully. We also use DEM to model reservoir geomechanical behavior beyond the elasticity limit where fractures can develop and faults can reactivate. A general technique has been developed to relate DEM parameters to rock properties. This is necessary in order to use correct reservoir geomechanical properties during modeling. For any type of particle packing there is a limitation that the maximum ratio between P- and S-wave velocity Vp/Vs that can be modeled is 3 . The static behavior for a loose packing is different from the dynamic behavior. Empirical relations are needed for the static behavior based on numerical test observations. The dynamic behavior for both dense and loose packing can be given by analytical relations. Cosserat continuum theory is needed to derive relations for Vp and Vs. It is shown that by constraining the particle rotation, the S-wave velocity can be

  2. Reservoir simulation with MUFITS code: Extension for double porosity reservoirs and flows in horizontal wells

    Science.gov (United States)

    Afanasyev, Andrey

    2017-04-01

    Numerical modelling of multiphase flows in porous medium is necessary in many applications concerning subsurface utilization. An incomplete list of those applications includes oil and gas fields exploration, underground carbon dioxide storage and geothermal energy production. The numerical simulations are conducted using complicated computer programs called reservoir simulators. A robust simulator should include a wide range of modelling options covering various exploration techniques, rock and fluid properties, and geological settings. In this work we present a recent development of new options in MUFITS code [1]. The first option concerns modelling of multiphase flows in double-porosity double-permeability reservoirs. We describe internal representation of reservoir models in MUFITS, which are constructed as a 3D graph of grid blocks, pipe segments, interfaces, etc. In case of double porosity reservoir, two linked nodes of the graph correspond to a grid cell. We simulate the 6th SPE comparative problem [2] and a five-spot geothermal production problem to validate the option. The second option concerns modelling of flows in porous medium coupled with flows in horizontal wells that are represented in the 3D graph as a sequence of pipe segments linked with pipe junctions. The well completions link the pipe segments with reservoir. The hydraulics in the wellbore, i.e. the frictional pressure drop, is calculated in accordance with Haaland's formula. We validate the option against the 7th SPE comparative problem [3]. We acknowledge financial support by the Russian Foundation for Basic Research (project No RFBR-15-31-20585). References [1] Afanasyev, A. MUFITS Reservoir Simulation Software (www.mufits.imec.msu.ru). [2] Firoozabadi A. et al. Sixth SPE Comparative Solution Project: Dual-Porosity Simulators // J. Petrol. Tech. 1990. V.42. N.6. P.710-715. [3] Nghiem L., et al. Seventh SPE Comparative Solution Project: Modelling of Horizontal Wells in Reservoir Simulation

  3. Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Mella, Michael [Univ. of Utah, Salt Lake City, UT (United States). Energy and Geoscience Inst.

    2016-08-31

    The objective of this project was to develop and demonstrate an approach for tracking the evolution of circulation immediately following a hydraulic stimulation in an EGS reservoir. Series of high-resolution tracer tests using conservative and thermally reactive tracers were designed at recently created EGS reservoirs in order to track changes in fluid flow parameters such as reservoir pore volume, flow capacity, and effective reservoir temperature over time. Data obtained from the project would be available for the calibration of reservoir models that could serve to predict EGS performance following a hydraulic stimulation.

  4. Method of extracting heat from dry geothermal reservoirs

    Science.gov (United States)

    Potter, R.M.; Robinson, E.S.; Smith, M.C.

    1974-01-22

    Hydraulic fracturing is used to interconnect two or more holes that penetrate a previously dry geothermal reservoir, and to produce within the reservoir a sufficiently large heat-transfer surface so that heat can be extracted from the reservoir at a usefully high rate by a fluid entering it through one hole and leaving it through another. Introduction of a fluid into the reservoir to remove heat from it and establishment of natural (unpumped) convective circulation through the reservoir to accomplish continuous heat removal are important and novel features of the method. (auth)

  5. Innovative MIOR Process Utilizing Indigenous Reservoir Constituents

    Energy Technology Data Exchange (ETDEWEB)

    D. O. Hitzman; A. K. Stepp; D. M. Dennis; L. R. Graumann

    2003-03-31

    This research program is directed at improving the knowledge of reservoir ecology and developing practical microbial solutions for improving oil production. The goal is to identify indigenous microbial populations which can produce beneficial metabolic products and develop a methodology to stimulate those select microbes with nutrient amendments to increase oil recovery. This microbial technology has the capability of producing multiple oil-releasing agents. Experimental laboratory work is underway. Microbial cultures have been isolated from produced water samples. Comparative laboratory studies demonstrating in situ production of microbial products as oil recovery agents were conducted in sand packs with natural field waters with cultures and conditions representative of oil reservoirs. Field pilot studies are underway.

  6. Mathematical simulation of oil reservoir properties

    International Nuclear Information System (INIS)

    Ramirez, A.; Romero, A.; Chavez, F.; Carrillo, F.; Lopez, S.

    2008-01-01

    The study and computational representation of porous media properties are very important for many industries where problems of fluid flow, percolation phenomena and liquid movement and stagnation are involved, for example, in building constructions, ore processing, chemical industries, mining, corrosion sciences, etc. Nevertheless, these kinds of processes present a noneasy behavior to be predicted and mathematical models must include statistical analysis, fractal and/or stochastic procedures to do it. This work shows the characterization of sandstone berea core samples which can be found as a porous media (PM) in natural oil reservoirs, rock formations, etc. and the development of a mathematical algorithm for simulating the anisotropic characteristics of a PM based on a stochastic distribution of some of their most important properties like porosity, permeability, pressure and saturation. Finally a stochastic process is used again to simulated the topography of an oil reservoir

  7. Great landslide events in Italian artificial reservoirs

    Directory of Open Access Journals (Sweden)

    A. Panizzo

    2005-01-01

    Full Text Available The empirical formulations to forecast landslide generated water waves, recently defined in the framework of a research program funded by the Italian National Dam Office RID (Registro Italiano Dighe, are here used to study three real cases of subaerial landslides which fell down italian artificial reservoirs. It is well known that impulse water waves generated by landslides constitute a very dangerous menace for human communities living in the shoreline of the artificial basin or downstream the dam. In 1963, the menace became tragedy, when a 270 millions m3 landslide fell down the Vajont reservoir (Italy, generated an impulse wave which destroyed the city of Longarone, and killed 2000 people. The paper is aimed at presenting the very satisfactorily reproduction of the events at hand by using forecasting formulations.  

  8. Great landslide events in Italian artificial reservoirs

    Science.gov (United States)

    Panizzo, A.; de Girolamo, P.; di Risio, M.; Maistri, A.; Petaccia, A.

    2005-09-01

    The empirical formulations to forecast landslide generated water waves, recently defined in the framework of a research program funded by the Italian National Dam Office RID (Registro Italiano Dighe), are here used to study three real cases of subaerial landslides which fell down italian artificial reservoirs. It is well known that impulse water waves generated by landslides constitute a very dangerous menace for human communities living in the shoreline of the artificial basin or downstream the dam. In 1963, the menace became tragedy, when a 270 millions m3 landslide fell down the Vajont reservoir (Italy), generated an impulse wave which destroyed the city of Longarone, and killed 2000 people. The paper is aimed at presenting the very satisfactorily reproduction of the events at hand by using forecasting formulations.

  9. Master equation and two heat reservoirs.

    Science.gov (United States)

    Trimper, Steffen

    2006-11-01

    A simple spin-flip process is analyzed under the presence of two heat reservoirs. While one flip process is triggered by a bath at temperature T, the inverse process is activated by a bath at a different temperature T'. The situation can be described by using a master equation approach in a second quantized Hamiltonian formulation. The stationary solution leads to a generalized Fermi-Dirac distribution with an effective temperature Te. Likewise the relaxation time is given in terms of Te. Introducing a spin representation we perform a Landau expansion for the averaged spin as order parameter and consequently, a free energy functional can be derived. Owing to the two reservoirs the model is invariant with respect to a simultaneous change sigma-sigma and TT'. This symmetry generates a third order term in the free energy which gives rise a dynamically induced first order transition.

  10. Overspill avalanching in a dense reservoir network

    Science.gov (United States)

    Mamede, George L.; Araújo, Nuno A. M.; Schneider, Christian M.; de Araújo, José Carlos; Herrmann, Hans J.

    2012-01-01

    Sustainability of communities, agriculture, and industry is strongly dependent on an effective storage and supply of water resources. In some regions the economic growth has led to a level of water demand that can only be accomplished through efficient reservoir networks. Such infrastructures are not always planned at larger scale but rather made by farmers according to their local needs of irrigation during droughts. Based on extensive data from the upper Jaguaribe basin, one of the world’s largest system of reservoirs, located in the Brazilian semiarid northeast, we reveal that surprisingly it self-organizes into a scale-free network exhibiting also a power-law in the distribution of the lakes and avalanches of discharges. With a new self-organized-criticality-type model we manage to explain the novel critical exponents. Implementing a flow model we are able to reproduce the measured overspill evolution providing a tool for catastrophe mitigation and future planning. PMID:22529343

  11. Microbial Enhanced Oil Recovery - Advanced Reservoir Simulation

    DEFF Research Database (Denmark)

    Nielsen, Sidsel Marie

    the water phase. The biofilm formation implies that the concentration of bacteria near the inlet increases. In combination with surfactant production, the biofilm results in a higher surfactant concentration in the initial part of the reservoir. The oil that is initially bypassed in connection...... simulator. In the streamline simulator, the effect of gravity is introduced using an operator splitting technique. The gravity effect stabilizes oil displacement causing markedly improvement of the oil recovery, when the oil density becomes relatively low. The general characteristics found for MEOR in one......-dimensional simulations are also demonstrated both in two and three dimensions. Overall, this MEOR process conducted in a heterogeneous reservoir also produces more oil compared to waterflooding, when the simulations are run in multiple dimensions. The work presented in this thesis has resulted in two publications so far....

  12. 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

  13. Nuclear stimulation of oil-reservoirs

    International Nuclear Information System (INIS)

    Delort, F.; Supiot, F.

    1970-01-01

    Underground nuclear explosions in the Hoggar nuclear test site have shown that the geological effects may increase the production of oil or gas reservoirs. By studying the permanent liquid flow-rate with approximate DUPUIT's equation, or with a computer code, it is shown that the conventional well flow-rate may be increased by a factor between 3 and 50, depending on the medium and explosion conditions. (author)

  14. Modelling souring in a high salinity reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Michael; Crossland, Alan; Stott, Jim

    2006-03-15

    CAPCIS Ltd (Capcis) have developed a souring model for use in highly saline reservoirs where salinity limits the growth of sulphate reducing bacteria (SRB). Capcis have successfully applied the model to a field in North Africa. The conceptual basis of the model considers the course of the H2S from generation in the reservoir including dilution, sulphide retardation and scavenging and H2S fluid phase partitioning. At each stage mathematical equations governing the behaviour of the H2S were produced. In order to estimate the potential for H2S generation, it is required to know the chemistry of the injection and formation waters, as well as the properties of the indigenous SRB, i.e. the maximum salinity for their growth. This is determined by bottle testing of H2S generation by SRB at a range of injection/formation water ratios. The maximum salinity for SRB growth then determines the mixing ratios at which H2S generation takes place. Sulphide retardation due to adsorption at immobile interfaces was empirically modeled from reservoir data. Sulphide scavenging due to reaction with iron generated from corrosion was also modelled. Reservoir mineral scavenging was not modelled but could be incorporated in an extension to the model. Finally, in order to compute the gas-phase concentration of generated H2S, the H2S in the well stream is partitioned between the gas, oil and water phases. Capcis has carried out detailed computations of H2S solubility in crude oil and formation waters and the derivation of distribution ratios based on the respective partition coefficients using Gerard's line method, a modification of Henry's Law. (author) (tk)

  15. Innovative MIOR Process Utilizing Indigenous Reservoir Constituents

    Energy Technology Data Exchange (ETDEWEB)

    Hitzman, D.O.; Stepp, A.K.; Dennis, D.M.; Graumann, L.R.

    2003-02-11

    This research program was directed at improving the knowledge of reservoir ecology and developing practical microbial solutions for improving oil production. The goal was to identify indigenous microbial populations which can produce beneficial metabolic products and develop a methodology to stimulate those select microbes with inorganic nutrient amendments to increase oil recovery. This microbial technology has the capability of producing multiple oil-releasing agents.

  16. Innovative MIOR Process Utilizing Indigenous Reservoir Constituents

    Energy Technology Data Exchange (ETDEWEB)

    Hitzman, D.O.; Bailey, S.A.; Stepp, A.K.

    2003-02-11

    This research program was directed at improving the knowledge of reservoir ecology and developing practical microbial solutions for improving oil production. The goal was to identify indigenous microbial populations which can produce beneficial metabolic products and develop a methodology to stimulate those select microbes with inorganic nutrient amendments to increase oil recovery. This microbial technology has the capability of producing multiple oil releasing agents. The potential of the system will be illustrated and demonstrated by the example of biopolymer production on oil recovery.

  17. Reservoir storage and containment of greenhouse gases

    Energy Technology Data Exchange (ETDEWEB)

    Weir, G.J.; White, S.P.; Kissling, W.M. [Industrial Research Ltd., Lower Hutt (New Zealand)

    1995-03-01

    This paper considers the injection of CO{sub 2} into underground reservoirs. Computer models are used to investigate the disposal of CO{sub 2} generated by an 800 MW power station. A number of scenarios are considered, some of which result in containment of the CO{sub 2} over very long time scales and others result in the escape of the CO{sub 2} after a few hundred years.

  18. Diffuser Operations at Spring Hollow Reservoir

    OpenAIRE

    Gantzer, Paul Anthony

    2002-01-01

    Stratification is a natural occurrence in deep lakes and reservoirs. This phenomenon results in two distinct layers, the warmer, less dense epilimnion on top and the colder, denser, hypolimnion on the bottom. The epilimnion remains saturated with dissolved oxygen (DO) from mass transfer with the atmosphere, while the hypolimnion continues to undergo oxygen-depleting processes. During seasons of high oxygen demand the hypolimnion often becomes anoxic and results in the release of compounds,...

  19. Nuclear stimulation of oil-reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Delort, F; Supiot, F [Commissariat a l' Energie Atomique, Centre d' Etudes de Bruyere-le-Chatel (France)

    1970-05-01

    Underground nuclear explosions in the Hoggar nuclear test site have shown that the geological effects may increase the production of oil or gas reservoirs. By studying the permanent liquid flow-rate with approximate DUPUIT's equation, or with a computer code, it is shown that the conventional well flow-rate may be increased by a factor between 3 and 50, depending on the medium and explosion conditions. (author)

  20. 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