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Kleopa, Xenia A. "Optimal reservoir operation for drought management." Ohio : Ohio University, 1990. http://www.ohiolink.edu/etd/view.cgi?ohiou1183650664.
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Kistenmacher, Martin. "Reservoir system management under uncertainty." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/49012.
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Reservoir systems are subject to several uncertainties that are the result of imperfect knowledge about system behavior and inputs. A major source of uncertainty arises from the inability to predict future inflows. Fortunately, it is often possible to generate probabilistic forecasts of inflow volumes in the form of probability density functions or ensembles. These inflow forecasts can be coupled with stochastic management models to determine reservoir release policies and provide stakeholders with meaningful information of upcoming system responses such as reservoir levels, releases, flood damage risks, hydropower production, water supply withdrawals, water quality conditions, navigation opportunities, and environmental flows, among others. This information on anticipated system responses is also expressed in the form of forecasts that must reliably represent the actual system behavior when it eventually occurs. The first part of this study presents an assessment methodology that can be used to determine the consistency of ensemble forecasts through the use of relative frequency histograms and minimum spanning trees (MST). This methodology is then used to assess a management model's ability to produce reliable ensemble forecasts. It was found that neglecting to account for hydrologic state variables and improperly modeling the finite management horizon decrease ensemble consistency. Several extensions to the existing management model are also developed and evaluated. The second portion of this study involves the management of the uncertainties in reservoir systems. Traditional management models only find management policies that optimize the expected values of system benefits or costs, thereby not allowing operators and stakeholders to explicitly explore issues related to uncertainty and risk management. A technique that can be used to derive management policies that produce desired probabilistic distributions of reservoir system outputs reflecting stakeholder preferences is developed. This technique can be embedded in a user-interactive framework that can be employed to evaluate the trade-offs and build consensus in multi-objective and multi-stakeholder systems. The methods developed in this dissertation are illustrated in case studies of real reservoir systems, including a seven-reservoir, multi-objective system in California's Central Valley.
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Najafiazar, Bahador. "Mathematical Optimization in Reservoir Management." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-27058.
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Getting the most out of a hydrocarbon reservoir is not a trivial task. It takes plentyof interwoven decisions to make. There are many forms of tools that support engineersto make correct decisions. The simplest ones would only display measurementsin a suitable way, and appoint the rest of the decision making processto human knowledge and experience. Complex decision support tools may implementmodel-based estimation and optimization. This work targets methods foroptimization-based decision support.The objective of this study is to formulate, implement and test promising methodsof hydrocarbon production optimization through various test cases. To do this, avarious optimizations algorithm were applied to the simulated reservoir modelsusing the Matlab Reservoir Simulation Toolbox (MRST).
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Garcia, Christopher Jacob. "Management of Global Reservoir Sedimentation: Evaluating RESCON 2 for Sediment Management Alternatives." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7505.
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Reservoir sedimentation occurs as dams impound streams and rivers, preventing the delivery of sediments downstream. Globally, reservoirs lose approximately 40 million acre-ft of storage to sediments each year. Several methods for managing reservoir sedimentation have been developed to help extend project life. In 2017, the World Bank sponsored REServoir CONservation (RESCON) 2, a pre-feasibility program aimed to help users select sediment management practices to consider for more detailed studies.There are two main objectives to this research: 1) perform a sensitivity analysis to understand which parameters require greater precision and which can be roughly approximated, and 2) evaluate RESCON 2 suggested practices to assess the model's accuracy and consistency for providing the optimal solution. Comparisons of the actual sediment management practice will be made with RESCON's results and applicable zones from the Sediment Management Options Diagram (SMOD). Brief descriptions of the SMOD and RESCON 2 will be provided. RESCON-required inputs will be summarized, and some key entries will be presented. Additionally, innovations taken in Japan to modify and retrofit exiting reservoirs with sediment management capabilities will be explored.The sensitivity analysis proves the unit benefit of reservoir yield parameter to be highly sensitive, and users should invest time into determining this value. The sensitivity analysis also illustrates certain processes in RESCON, such as automatically determining the implementation schedule of flushing or a sustainable solution for dredging operations, have great influence over the respective method's analysis. Approximations can be used if these options were selected.Twenty reservoirs from around the world were modeled in RESCON 2, with storage capacities ranging between 152 acre-ft and 31.9 million acre-ft. All sediment management alternatives whose NPV lied within 30% of the highest alternative were deemed practicable for the reservoir. Of the twenty models analyzed in RESCON 2, ten did not practice sediment management. Analyzing only those reservoirs where sediment management is being employed, RESCON predicted the correct or used practice eight out of ten times.Recommendations to improve RESCON include 1) an HSRS operations and maintenance parameter, 2) expanding the unit benefit of reservoir yield parameter into several terms to more explicitly state applicable revenue sources, and 3) creating a list of RESCON model builds, updates, and bug treatments and an option for users to report bugs or other problems.
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Moore, David L. "Reservoir management during drought an expert system approach." Ohio : Ohio University, 1993. http://www.ohiolink.edu/etd/view.cgi?ohiou1175718241.
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Kaseke, Evans. "Fuzzy linear programming and reservoir management." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26708.
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The presence of imprecision in parameter specification of water resources
management problems leads to the formulation of fuzzy programming
models. This thesis presents the formulation of a two-reservoir system problem as a fuzzy L.P. model. The aim is to determine if larger monetary
benefits, over and above the usual benefits, can be obtained from the system. The other aim is to determine if desired industrial and domestic water allocations, as well as outflows for selected periods can be achieved.
The problem is formulated as a conventional L.P. model. Then selected water allocations and outflows are fuzzified resulting in a fuzzy L.P. model. The alternative fuzzy L.P. model is also presented.
Monetary benefits larger than those from the conventional L.P. were obtained through the fuzzy L.P. model. The desired water allocations and outflows were also realised for selected periods. Sensitivity information was obtained for fuzzy and non-fuzzy constraints. The alternative fuzzy L.P. model did not give additional valuable information than that obtained from the initial fuzzy L.P. model.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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King, James Allen. "Optimal reservoir operation for drought management." Ohio University / OhioLINK, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1183649698.
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Buchanan, Crawford S. "Benders decomposition method in reservoir management." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/22790.
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Multi-stage stochastic linear programming provides a framework in which to model and solve decision making problems that contain uncertain data. In this thesis the main stages in the process of modelling and solving a large-scale multi-stage stochastic linear programme (MSLP) are examined. The principal motivation for this research is the study of the electricity generation network of Southern Brazil. This network contains a high proportion of hydro-electric generation plants, and so the stochasticity of the future inflows has a large influence on decisions. The formulation of MSLPS is difficult within existing algebraic modelling languages. Many MSLPs can be formulation as a set of recurrences. We present a new algebraic modelling language, sMAGIC, that uses the recursive definition of sub-models to aid in the specification of MSLPs. The Benders Decomposition algorithm exploits the sparse structure of MSLPs, achieving a considerable reduction in the time taken to solve MSLPs over direct solution methods, such as the simplex method. In addition, the basic Benders Decomposition algorithm can be extended and is well suited to parallelisation. We present results that show that some of the extensions to the basic algorithm improve the performance of the solver in all cases, while others provide improvements only for particular test problems. The research from our parallel implementation on a network of workstations give near linear speedups. Sampling techniques can be incorporated within the Benders Decomposition method. This allows an approximation to the solution of MSLPs that are too large to solve using Benders Decomposition to be obtained. A Benders Decomposition algorithm that incorporates Monte Carlo is guaranteed to converge asymptotically to the actual solution. To improve the speed of this algorithm, an additive approximation to the cost function is used to guide an importance sampling technique.
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Xie, Ming 1973. "Prediction of daily net inflows for management of reservoir systems." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33043.
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Operational planning of water resource systems like reservoirs and hydropower plants calls for real-time forecasting of reservoir inflow. Reservoir daily inflow forecasts provide a warning of impending floods or drought conditions and help to optimize operating policies for reservoir management based on a fine time scale. The aim of this study was to determine the best model for daily reservoir inflow prediction through linear regression, exponential smoothing and artificial neural network (ANN) techniques. The Hedi reservoir, the third largest reservoir in south China with a 1.144 x 109 m 3, was selected as the study site. The performance of these forecasting models, in terms of forecasting accuracy, efficiency of model development and adaptability for future prediction, were compared to one another. All models performed well during the dry season (inflow with low variability), while the non-linear ANNs were superior to other models in frontal rainy season and typhoon season (inflow with high variability). The performance of ANN models were hardly affected by the high degree of uncertainty and variability inherent to the rainy season. Stepwise selection was very helpful in identifying significant variables for regression models and ANNs. This procedure reduced ANN's size and greatly improved forecasting accuracy for ANN models. The impact of training data series, model architecture and network internal parameters on ANNs performances were also addressed in this study. The overall evaluation indicates that ANNs are an effective and robust tool for input-output mapping under more extreme and variable conditions. ANNs provide an alternative forecasting approach to conventional time series forecasting models for daily reservoir inflow prediction.
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Adams, Lauren. "Optimized Reservoir Management for Downstream Environmental Purposes." Thesis, University of California, Davis, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10973511.
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In regulated rivers, reservoir operation decisions largely determine downstream river temperature and flow. Computational methods can minimize the risk and uncertainty of making regrettable environmental release decisions and aid operations planning and performance prediction. Mathematical modeling in particular can optimize the timing and magnitude of reservoir release decisions for downstream benefit while accounting for seasonal uncertainty, water storage impact, and competing water demands. This dissertation uses optimization and modeling techniques, modifying traditional optimization modeling to include temporal correlation in outcome variables and incorporating long-term planning and risk management into prescribed reservoir operations. The proposed method is implemented in one case, a) with a state variable that tracks outcome benefits over time (fish population size) and, in another case, b) with a maximin stochastic dynamic program solution algorithm that maximizes net operational benefit and minimizes worst-case outcomes (for cold water habitat delivery). This method is particularly useful for environmental flow management, when the water quality and quantity of the river and reservoir in one time step affect the quantity and quality in the reservoir and the river for later periods. Better solutions with these methods internalize risk and hedge releases at the beginning of an operating season to maximize downstream benefit and reduce the probability of catastrophe for the season and future years. Maximizing the minimum cold-water habitat area over months of a season or multiple years, or maximizing a river indicator variable explicitly, could likely help, for example, maximize an out-migrating salmon smolt population downstream. The method is demonstrated with a case study optimizing environmental releases from Folsom Dam and another optimizing temperature management from Shasta Dam in northern California. These results inform general rules for environmental flow management and temperature management of reservoirs, with specific policy recommendations for both Folsom and Shasta reservoirs. In both cases, the added value from employing hedging rules help reservoir operations minimize the risk of environmental catastrophe and conserve storage both within an operating season and across years.
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Joinson, Daniel. "Subterranean wireless communication for oil reservoir management." Thesis, University of Cambridge, 2005. https://www.repository.cam.ac.uk/handle/1810/272141.
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Gomes, Jorge S. "Reservoir description of the Arab-C Dukhan carbonate reservoir for improved reservoir management and use as a subsurface analogue." Thesis, Heriot-Watt University, 2001. http://hdl.handle.net/10399/1141.
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Cetinkaya, Oguz Kagan. "Management Of Reservoir Sedimentation Case Studies From Turkey." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607016/index.pdf.
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Siltation is becoming a big problem as the dams get older all over the world. Conservation and sustainable management of existing reservoirs is gaining more importance than constructing new dams. In this study the program RESCON, which is outcome of a World Bank sponsored project, has been used to examine sediment removal strategies (flushing, hydrosuction sediment removal, dredging and trucking) for four dams of Turkey namely Çubuk I Dam, Bayindir Dam, ivriz Dam and Borç
ka Dam. Sediment measurements are made by governmental agencies in Turkey. In this study characteristics of these measurements will be presented for the future sediment related studies. Then sediment removal strategies which were used in RESCON will be introduced. Evaluation of RESCON results have been made and compared with previous studies for verification except Borç
ka Dam, since it is under construction.
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Mamede, George Leite. "Reservoir sedimentation in dryland catchments : modelling and management." Phd thesis, Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2008/1704/.
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Semi-arid environments are mainly characterized by scarce water resources and are usually subject to risks of water stress. In these regions, water supply for drinking and irrigation purposes depends strongly on storage in surface reservoirs and sediment deposition in these reservoirs affects adversely the water storage.
In order to reproduce the complex behaviour of sediment deposition in reservoirs located in semi-arid environments and the effects of using sediment management techniques, a reservoir sedimentation model is developed and coupled within the WASA-SED model, which simulates rainfall-runoff processes and sediment transport at the hillslope and river network.
The reservoir sedimentation model consists of two modelling approaches, which may be applied according to reservoir size and data availability. For reservoirs with information about their geometric features (reservoir topography, stage-area and stage-volume curves) and physical properties of sediment deposits, such as deposition thickness, grain size distribution of sediment deposits and sediment densities, a detailed modelling approach of reservoir sedimentation may be applied. For reservoirs without those characteristics, a simplified modelling approach is used.
The detailed modelling approach of reservoir sedimentation enables the assessment of sediment deposition pattern in reservoirs and the evaluation of sediment release efficiency of sediment management techniques. It simulates sediment transport along the longitudinal profile of a reservoir. The reservoir is divided into cross sections to elaborate the sediment budget. The sediment transport component is calculated using a non-uniform sediment transport approach based on the concept of sediment carrying capacity. Four different sediment-transport equations can be selected for the simulations.
The simplified modelling approach of reservoir sedimentation is suitable to simulate water and sediment transfer in dense reservoirs network. Nevertheless, it allows simulating neither sediment management techniques, nor spatial distribution of sedimentation. In this approach, the reservoirs are classified into small and strategic reservoirs according to their location and size. Strategic reservoirs are medium and large-sized reservoirs located on main rivers at the sub-basin’s outlet or reservoirs of particular interest. The small reservoirs are located at tributary streams and represented in the model in an aggregate manner by grouping them into size classes according to their storage capacity. A cascade routing scheme is used to describe the upstream-downstream position of the reservoir classes. The water and sediment balances of small reservoirs are computed for one hypothetical representative reservoir of mean characteristics. Sediment trapping efficiency and effluent grain size distribution are estimated using the overflow rate concept.
Three model applications are carried out within this research, as follows:
• The detailed modelling approach of reservoir sedimentation is applied to the 92.2 Mm³ Barasona Reservoir, located in the foothills of the Central Pyrenees (Aragon, Spain). A two-stage calibration was performed to account for changes on the sediment deposition pattern caused by sediment management. The reservoir sedimentation model is then validated for another simulation period which confirms that the processes related to reservoir sedimentation are well represented by the model.
• An application is carried out to the 933-km² Benguê catchment, located in the semi-arid region of Northeast Brazil. The catchment is characterized by a dense reservoir network, covering almost 45% of the catchment area, with a significant lack of data. Water and sediment balances of those reservoirs are computed using the simplified modelling approach. Three spatial configurations describing the cascade routing scheme are tested.
• The reservoir sedimentation model is applied again to the Barasona reservoir to evaluate the sediment release efficiency of sediment management strategies. Cost analysis is presented to help in the choice of the most promising sediment management technique for that situation. Thus, the model enables the assessment of technical features of the sediment management strategies.
Overall, simulation results are characterized by large uncertainties, partly due to low data availability and also due to uncertainties of the model structure to adequately represent the processes related to reservoir sedimentation.Semiaride Gebiete sind hauptsächlich durch geringe Wasserressourcen gekennzeichnet und unterliegen häufig dem Risiko der Wasserknappheit. In diesen Gebieten ist die Wasserbereitstellung für Bewässerung und Trinkwasserversorgung stark von der oberflächlichen Speicherung in Stauseen abhängig, deren Wasserverfügbarkeit nachteilig durch Sedimentablagerung beeinflusst wird. Zur Wiedergabe des komplexen Sedimentablagerungsverhaltens in Stauseen von semiariden Gebieten und die Auswirkungen von Sedimentmanagementmaßnahmen wird ein Sedimentationsmodell entwickelt und mit dem WASA-SED Modell gekoppelt, das für die Modellierung der Abflussbildung und des Sedimenttransportes in Einzugsgebieten geeignet ist. Das Sedimentationsmodell beinhaltet zwei Ansätze, die unter der Berücksichtigung verschiedener Stauseengrößenklassen und Datenverfügbarkeit eingesetzt werden können. Für die Stauseen mit verfügbaren Informationen über ihre geometrischen Eigenschaften (wie Stauseetopographie und Höhe-Fläche-Volumen-Beziehung) und weitere Kenngrößen wie Ablagerungsmächtigkeit, Korngrößenverteilung und Sedimentdichte, kann ein detaillierter Modellansatz für die Sedimentablagerung verwendet werden. Wo diese Informationen nicht verfügbar sind, wird auf einen vereinfachten Ansatz zurückgegriffen. Der detaillierte Modellansatz ermöglicht die Betrachtung von Ablagerungsmustern im Stausee und Einschätzungen über die Effektivität von Sedimentmanagementmaßnahmen hinsichtlich der Sedimententlastung. Dieser Ansatz beruht auf der Simulation des Sedimenttransportes entlang eines Stauseelängsprofils. Für die Berechnung des Sedimenttransfers wird der Stauseekörper in einer Folge von Querprofilen repräsentiert. Der Sedimenttransport wird dabei korngrößenspezifisch entsprechend der Transportkapazität berechnet. Dafür stehen vier verschiedenen Sedimenttransportgleichungen zur Verfügung. Der vereinfachte Modellansatz ist für die Simulation des Sedimenttransfers in Gebieten mit hoher Stauseedichte geeignet, jedoch können weder Sedimentmanagementmaßnahmen noch die räumliche Verteilung der Ablagerungen berücksichtigt werden. Dafür werden die Stauseen in Abhängigkeit von ihrer Größe und Position in kleine und strategische Stauseen unterteilt. Dabei sind strategische Stausseen solche mit mittlerem bis großem Volumen sowie einer Lage im Hauptgerinne oder solche mit sonstiger besonderer Bedeutung. Kleine Stauseen hingegen befinden sich an den Nebenflüssen und werden im Modell in aggregierter Form durch ihre Einteilung in Stauseegrößenklassen repräsentiert. Ein Kaskadenverfahren wird für den Wasser- und Sedimentlauf zwischen den Stauseeklassen verwendet. Dabei werden für jede Stauseeklasse der Wasser- sowie Sedimenthaushalt für einen hypothetischen repräsentativen Stausee mit mittleren Eigenschaften berechnet. Die Sedimentaufnahme und die Korngrößenverteilung des abgegebenen Sediments werden mit dem Überlaufanteil-Ansatz berechnet. In dieser Studie werden drei Modellanwendungen vorgestellt: • Für den 92,2 Mio.m³-großen Barasona-Stausee (Vorland der Zentralpyrenäen, Aragon, Spanien) wird die Modellierung der Sedimentablagerung mit dem detaillierten Modellansatz vorgenommen. Die Kalibrierung dafür wurde in zwei Schritten durchgeführt, um Änderungen im Stauseemanagement Rechnung zu tragen. Die ModellValidierung wird schließlich für eine andere Simulationsperiode vorgenommen. Dabei wird ersichtlich, dass die Prozesse der Sedimentablagerung gut durch das Modell wiedergegeben werden. • Das Modell wird auf das 933 km²-große Benguê-Einzugsgebiet, das sich im semiariden Nordosten Brasiliens befindet, angewendet. Dieses Einzugsgebiet ist durch eine hohe Dichte an kleinen Stauseen, charakterisiert, die fast 45% des Gebietes umfasst, wofür jedoch wenige Messdaten verfügbar sind. Deshalb werden der Wasser- und Sedimenttransport mit dem vereinfachten Modellansatz berechnet. Dabei werden drei Konfigurationen des Kaskadenverfahrens getestet. • Die Modellanwendung erfolgt erneut für den Barasona-Stausee bezüglich der Effektivität der Sedimentmanagementmaßnahmen. Eine Kostenanalyse ermöglicht die Auswahl geeigneter Maßnahmen für den Stausee. Dadurch wird eine Beurteilung der verschiedenen Sedimentmanagementstrategien ermöglicht. Im Allgemeinen unterliegen die Simulationsergebnisse großen Unsicherheiten, teilweise wegen der geringen Datenverfügbarkeit, andererseits durch die Unsicherheiten in der Modellstruktur zur korrekten Wiedergabe der Sedimentablagerungsprozesse.
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Alghareeb, Zeid M. "Optimal reservoir management using adaptive reduced-order models." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97792.
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Thesis: Ph. D. in Computational Science for Energy Resources Engineering, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 221-231).
Reservoir management and decision-making is often cast as an optimization problem where we seek to maximize the field's potential recovery while minimizing associated operational costs. Two reservoir management aspects are considered here, new well placement and production controls. Reservoir simulators are at the heart of this process as they aid in identifying best field development plans. The computational cost associated with managing realistic reservoirs is however substantial due to the significant number of unknowns evaluated by the simulator as well as the number of simulations required to achieve an optimal plan-it involves hundreds to thousands of reservoir simulation runs. Reduced-order models (ROM) are considered powerful techniques to address computational challenges associated with reservoir management decision-making. In this sense, they represent perfect alternatives that trade off accuracy for speed in a controllable manner. In this work, we focus on developing model-order reduction techniques that entail the use of proper orthogonal decomposition (POD), truncated balanced realization (TBR) and discrete empirical interpolation (DEIM) to accurately reproduce the full-order model (FOM) input/output behavior. POD allows for a concise representation of the FOM in terms of relatively few variables while TBR improves the overall stability and accuracy. DEIM improves the shortcomings of POD and TBR in the case of nonlinear PDEs, i.e., saturation equation, by retaining nonlinearities in lower dimensional space. Example cases demonstrate ROMs ability to reduce the computational costs by 0(100) while providing close overall agreement to FOM for instances with significant difference in boundary conditions (well placements and controls). ROMs are potentially perfect alternatives to FOMs in reservoir management intensive studies such as field development and optimization. However, ROMs presented in this thesis and the overall physics-based ROMs have the tendency to perform well within a restricted zone. This zone is generally dictated by the training simulations (with a specific set of boundary conditions) used to build the ROM. Therefore, special care is considered when implementing these training runs. To mitigate the heuristic process of implementing training runs (multiple boundary conditions training runs), we apply a trust-region approach that provides an adaptive framework to systemically retrain and update ROMs utilizing new solutions (flow) characteristics revealed during the course of the optimization run. The adaptive framework for determining the optimal well placements entails the development of a hybrid optimization algorithm, MCSMADS, that combines positive features of both local and global optimization methods. Typical FOM is used in conjunction with MCS to globally search the optimization surface while ROMs are used in conjunction with MADS to further improve the solution quality with minimum increase in computational costs. Well production controls are optimized sequentially via gradient-based trust-region approach. ROMs in this approach replace the FOM to find optimal solutions within a trust-region (subset of the optimization space). At the end of each trust-region optimization, the accuracy of the obtained solution is assessed and the ROM is updated. Both approaches are capable of handling nonlinear constraints. They are treated using a filter-based technique. The developed framework for adaptive ROMs is applied to two realistic field examples. The first example considers maximizing net present value (NPV) through sequentially optimizing well placements and controls while the second example considers maximizing recovery through minimizing Lorenz coefficient. Nonlinear constraints including well-to-well distance and field production limits are imposed in both examples. For all cases considered, the hybrid approach for well placement based on MCS-MADS was able to constantly provide better solution quality (up to 22% increase in NPV) when compared to standalone MCS with only 3% increase in computational costs. The incorporation of ROMs for well controls was shown to reduce computational cost by 96% with only 1% difference in solution quality when compared to FOM.
by Zeid M. Alghareeb.
Ph. D. in Computational Science for Energy Resources Engineering
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Helfer, Fernanda. "Influence of Air-Bubble Plumes and Effects of Climate Change on Reservoir Evaporation." Thesis, Griffith University, 2012. http://hdl.handle.net/10072/365996.
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It is estimated that open water reservoirs in Australia lose around 40% of their total water storage capacity per year to evaporation. This can be attributed to the country’s dry climate, with high temperatures and strong winds. To further exacerbate this issue, temperature increases have been recorded during the past decades, and this is predicted to continue over the coming years in Australia. This has been directing even greater concern to how much water will be lost from Australian reservoirs in the future through the evaporation process.
For several decades, Australia has been investigating mechanisms to minimize evaporation from reservoirs. These include the use of physical and chemical covers, windbreaks and even modifying the reservoir shape in order to reduce its surface area. Most of these techniques however, have been shown to be ineffective, as in the example of windbreaks; to be excessively expensive, as in the example of physical covers and modifying the reservoir shape; or to impose potential risks to the water quality, as in the use of chemical covers. Destratification by air-bubble plumes, which involves pumping compressed air into the interior of a reservoir, thereby allowing the resultant bubbles to rise and carry cold bottom water to the surface, is one technique that deserves further investigation. Air-bubble plumes have been suggested in literature as a potential mechanism for reducing evaporation from reservoirs due to their potential effects on water temperature change.
The primary aim of destratification by air-bubble plumes is to maintain or improve the quality of the reservoir water, specifically by increasing dissolved oxygen in the water. The potential of these systems to reduce evaporative losses is related to the change in water temperature attributable to mixing. The intuitive principle is that cold hypolimnetic water is lifted by the air bubbles, and once at the surface, this water mixes with the lighter epilimnetic water, reducing its temperature and consequently, evaporation rates.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
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Saad, Maarouf. "Application of principal components analysis to long-term reservoir management." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75910.
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Determining the optimal long-term operating policy of a multi-reservoir power system requires solution of a stochastic nonlinear programming problem. For small systems, the solution can be found by dynamic programming, but for large systems no direct solution method exists yet, so that one must resort to mathematical manipulations to solve the problem. This thesis presents a very efficient procedure for the case where high correlation exists between the state variables. It consists in performing principal components analysis on the trajectories to find a reduced model of the system. The reduced model is then substituted into the operating problem and the resulting problem is solved by stochastic dynamic programming. The reservoir trajectories on which principal components analysis are performed can be obtained by solving the operating problem deterministically for a large number of equally likely flow sequences. The results of applying the manipulation to Quebec's La Grande river, which has four reservoirs, are reported. A comparison with the classical dynamic programming, that is without any reduction, is also studied and results are reported to show the efficiency of the principal components approach.
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Mackay, Eric James. "The application of reservoir simulation calculations to oilfield scale management." Thesis, Heriot-Watt University, 2005. http://hdl.handle.net/10399/224.
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Kallis, Jahn L. "An ecological approach to management of an important reservoir fishery." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1376957161.
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Seetha, Ram Katakam V. "Conjunctive And Multipurpose Operation Of Reservoirs Using Genetic Algorithms." Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/222.
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Optimal operation of reservoir systems is necessary for better utilizing the limited water resources and to justify the high capital investments associated with reservoir projects. However, finding optimal policies for real-life problems of reservoir systems operation (RSO) is a challenging task as the available analytical methods can not handle the arbitrary functions of the problem and almost all methods employed are numerical or iterative type that are computer dependent. Since the computer resources in terms of memory and CPU time are limited, a limit exists for the size of the problem, in terms of arithmetic and memory involved, that can be handled. This limit is approached quickly as the dimension and the nonlinearity of the problem increases.
In encountering the complex aspects of the problem all the traditionally employed methods have their own drawbacks. Linear programming (LP), though very efficient in dealing with linear functions, can not handle nonlinear functions which is the case mostly in real-life problems. Attempting to approximate nonlinear functions to linear ones results in the problem size growing enormously. Dynamic programming (DP), though suitable for most of the RSO problems, requires exponentially increasing computer resources as the dimension of the problem increases and at present many high dimensional real-life problems can not be solved using DP. Nonlinear programming (NLP) methods are not known to be efficient in RSO problems due to slow rate of convergence and inability to handle stochastic problems. Simulation methods can, practically, explore only a small portion of the search region. Many simplifications in formulations and adoption of approximate methods in literature still fall short in addressing the most critical aspects, namely multidimensionality, stochasticity, and additional complexity in conjunctive operation, of the problem. As the problem complexity increases and the possibility of arriving at the solution recedes, a near optimal solution with the best use of computational resources can be very valuable. In this context, genetic algorithms (GA) can be a promising technique which is believed to have an advantage in terms of efficient use of computer resources.
GA is a random search method which find, in general, near optimal solutions using evolutionary mechanism of natural selection and natural genetics. When a pool of feasible solutions, represented in a coded form, are given fitness according to a objective function and explored by genetic operators for obtaining new pools of solutions, then the ensuing trajectories of solutions come closer and closer to the optimal solution which has the greatest fitness associated with it. GA can be applied to arbitrary functions and is not excessively sensitive to the dimension of the problem. Though in general GA finds only the near optimal solutions trapping in local optima is not a serious problem due to global look and random search.
Since GA is not fully explored for RSO problems two such problems are selected here to study the usefulness and efficiency of GA in obtaining near optimal solutions. One problem is conjunctive operation of a system consisting of a surface reservoir and an aquifer, taken from the literature for which deterministic and stochastic models are solved. Another problem is real-time operation of a multipurpose reservoir, operated for irrigation (primary purpose) and hydropower production, which is in the form of a case study.
The conjunctive operation problem consists of determining optimal policy for a combined system of a surface reservoir and an aquifer. The surface reservoir releases water to an exclusive area for irrigation and to a recharge facility from which it reaches the aquifer in the following period. Another exclusive area is irrigated by water pumped from the aquifer. The objective is to maximize the total benefit from the two irrigated areas. The inflow to the surface reservoir is treated as constant in deterministic model and taken at 6 different classes in stochastic model. The hydrological interactions between aquifer and reservoir are described using a lumped parameter model in which the average aquifer water table is arrived at based on the quantity of water in the aquifer, and local drawdown in pumping well is neglected. In order to evaluate the GA solution both deterministic and stochastic models are solved using DP and stochastic DP (SDP) techniques respectively. In the deterministic model, steady state (SS) cyclic (repetitive) solution is identified in DP as well as in GA. It is shown that the benefit from GA solution converges to as near as 95% of the benefit from exact DP solution at a highly discounted CPU time.
In the stochastic model, the steady state solution obtained with SDP consists of converged first stage decisions, which took a 8-stage horizon, for any combination of components of the system state. The GA solution is obtained after simplifying the model to reduce the number of decision variables. Unlike SDP policy which gives decisions considering the state of the system in terms of storages, at reservoir, aquifer, and recharge facility, and previous inflow at the beginning of that period, GA gives decisions for each period of the horizon considering only the past inflow state of the period. In arriving at these decisions the effect of neglected state information is approximately reflected in the decisions by the process of refinement of the decisions, to conform to feasibility of storages in reservoir and aquifer, carried out in a simplified simulation process. Moreover, the validity of the solution is confirmed by simulating the operation with all possible inflow sequences for which the 8-stages benefit converged up to 90 % of the optimum. However, since 8 stages are required for convergence to SS, a 16-stage process is required for GA method in which the first 8 stages policy is valid. Results show that GA convergence to the optimum is satisfactory, justifying the approximations, with significant savings in CPU time.
For real-time operation of a multipurpose reservoir, a rule curve (RC) based monthly operation is formulated and applied on a real-life problem involving releases for irrigation as well as power production. The RC operation is based on the target storages that have to be maintained, at each season of the year, in the reservoir during normal hydrological conditions. Exceptions to target storages are allowed when the demands have to be met or for conserving water during the periods of high inflows. The reservoir in the case study supplies water to irrigation fields through two canals where a set of turbines each at the canal heads generate hydropower. A third set of turbines operate on the river bed with the water let out downstream from the dam. The problem consists of determining the the RC target storages that facilitate maximum power production while meeting the irrigation demands up to a given reliability level. The RC target storages are considered at three different levels, corresponding to dry, normal, and wet conditions, according to the system state in terms of actual (beginning of period) storage of the reservoir. That is, if the actual beginning storage of the reservoir is less than some coefficient, dry-coe, times the normal target storage the target for the end of the period storage is taken at the dry storage target (of the three sets of storages). Similarly the wet level is taken for the end of the period target if the actual beginning storage is greater than some coefficient, wet-coe, times the normal storage. For other conditions the target is the normal storage level.
The dry-coe and wet-coe parameters are obtained by trial and error analysis working on a small sequence of inflows. The three sets of targets are obtained from optimization over a 1000 year generated inflow sequence. With deterministic DP solutions, for small sequences of inflows, the optimization capability of GA-RC approach, in terms of objective function convergence, and generalization or robustness capability of GA-RC approach, for which the GA-RC benefit is obtained by simulating the reservoir operation using the previously obtained GA-RC solution, are evaluated. In both the cases GA-RC approach proves to be promising. Finally a 15 year real-time simulation of the reservoir is carried out using historical inflows and demands and the comparison with the historical operation shows significant improvement in benefit, i.e. power produced, without compromising irrigation demands throughout the simulation period.
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Nwankwor, Emeka. "A unified metaheuristic and system-theoretic framework for petroleum reservoir management." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/16993/.
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With phenomenal rise in world population as well as robust economic growth in China, India and other emerging economies; the global demand for energy continues to grow in monumental proportions. Owing to its wide end-use capabilities, petroleum is without doubt, the world’s number one energy resource. The present demand for oil and credible future forecasts – which point to the fact that the demand is expected to increase in the coming decades – make it imperative that the E&P industry must device means to improve the present low recovery factor of hydrocarbon reservoirs. Efficiently tailored model-based optimization, estimation and control techniques within the ambit of a closed-loop reservoir management framework can play a significant role in achieving this objective. In this thesis, some fundamental reservoir engineering problems such as field development planning, production scheduling and control are formulated into different optimization problems. In this regard, field development optimization identifies the well placements that best maximizes hydrocarbon recovery, while production optimization identifies reservoir well-settings that maximizes total oil recovery or asset value, and finally, the implementation of a predictive controller algorithm which computes corrected well controls that minimizes the difference between actual outputs and simulated (or optimal) reference trajectory. We employ either deterministic or metaheuristic optimization algorithms, such that the choice of algorithm is purely based on the peculiarity of the underlying optimization problem. Altogether, we present a unified metaheuristic and system-theoretic framework for petroleum reservoir management. The proposed framework is essentially a closed-loop reservoir management approach with four key elements, namely: a new metaheuristic technique for field development optimization, a gradient-based adjoint formulation for well rates control, an effective predictive control strategy for tracking the gradient-based optimal production trajectory and an efficient model-updating (or history matching) – where well production data are used to systematically recalibrate reservoir model parameters in order to minimize the mismatch between actual and simulated measurements. Central to all of these problems is the use of white-box reservoir models which are employed in the well placement optimization and production settings optimization. However, a simple data-driven black-box model which results from the linearization of an identified nonlinear model is employed in the predictive controller algorithm. The benefits and efficiency of the approach in our work is demonstrated through the maximization of the NPV of waterflooded reservoir models that are subject to production and geological uncertainty. Our procedure provides an improvement in the NPV, and importantly, the predictive control algorithm ensures that this improved NPV are attainable as nearly as possible in practice.
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Kerr, Andrew L. "Stochastic utility maximising dynamic programming applied to medium-term reservoir management." Thesis, University of Canterbury. Management, 2003. http://hdl.handle.net/10092/4501.
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Medium-term reservoir management is a classic planning problem to which stochastic dynamic programming has been applied. An aspect of reservoir management modelling often neglected is 'risk', although it has been identified as being of prime importance. A utility function can imply an attitude to risk, and in this thesis, a modified stochastic dynamic programming model (SUMDP) is presented which can maximise expected utility, where utility is defined over the range of terminal storage and 'wealth' outcomes and hence is dependent on all decisions made over the planning horizon.
SUMDP is applied to reservoir management in regulated and deregulated representations of the New Zealand electricity system. Experimental results showed that increasing the relative risk aversion to low terminal wealth values reduced the mean and variability of wealth and was achieved by conserving water and hence increasing storage. This effect was amplified by the contract level of the hydro firm in a deregulated case where the reservoir firm was a price setter with financial contracts and the remaining players were price takers.
SUMDP can be applied to other problem classes, one of which is stochastic route choice in acyclic networks. SUMDP is discussed in this context and applied to some example problems. Rather than a single (static) route choice decision being optimal at each node of the network, SUMDP produces optimal non-static decisions which are dependent on the accumulated time taken to reach the node and take into account the utility associated with the time taken to travel the route. There are few approaches discussed in the literature which produce non-static solutions, consider uncertainty, and consider risk, so SUMDP also contributes to this literature.
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Scott, Tristram J. "Hydro reservoir management for an electricity market with long-term contracts." Thesis, University of Canterbury. Management, 1998. http://hdl.handle.net/10092/4503.
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This Thesis deals with the management of a mixed hydro-thermal system in a competitive electricity market. A notable feature of our market is the presence of long term financial contracts, or options. We model the energy spot market as a Cournot oligopoly, with a non-competitive fringe. The data from the Cournot model is used in an optimisation model based on Dual Dynamic Programming (DDP). The optimisation model produces operating rules in the form of a marginal water value surface, and these rules guide our medium term simulation model.
We develop a method for using the Cournot model to produce Demand Curves for Release, which describe the amount of water the hydro manager would want to release in a given period for a range of marginal water values (prices). We show how DDP can be thought of as a process of adding demand curves over time, equating marginal costs between periods.
We find that the efficiency of the market is greatly influenced by the size of the contracts, and to a lesser extent by the portfolio of plant that each of the firms has. Increasing contracts lead to increasing output, decreasing spot prices, decreasing profit, increasing consumer surplus, decreasing marginal water values, and increasing storage trajectories. With appropriate choice of contracts the market can be made to mimic perfect competition.
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Krause, Kari. "An archaeological resource management plan for the Brookville Reservoir, Brookville, Indiana." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/935927.
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This thesis provides a comprehensive view of the archaeological resources located around Brookville Lake, as well as an overall management plan regarding the care and significance of each recorded site and the reservoir as a whole.Brookville Lake, constructed by the U.S. Army Corps of Engineers, opened in 1975. The main functions of Brookville Lake are flood control, water supply, recreation, and resource management. The total area encompassed within the reservoir is 11,185 acres, with the lake comprising 5,260 acres.To construct an archaeological resource management plan for the Brookville Lake Reservoir, extensive background research on all archaeological work within the Lake area was completed. This included both the early antiquarian work and more recent contract archaeological surveys done in the Whitewater River drainage. The examination of recorded historic and prehistoric archaeological sites was also discussed because of the potential historical significance of the property.Taking into account all previous work done in the reservoir and the incompleteness of the data regarding the presence of archaeological resources within the property, a research design was formulated for the completion of an archaeological survey.Finally, the development of management possibilities for the archaeological resources took into account legislation and the U.S. Army Corps of Engineers' master plan of development for the reservoir, the most recent plan dating to 1986.Department of Anthropology
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Duras, Jan. "Studie udržitelného managementu příměstské rekreační nádrže." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-124978.
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The aim of the study was to analyse possibilities of sustainable use of a recreational lake in the outskirts of the City Plzeň. Long term balance between economic, social and ecological aspects was emphasized. After the analyse was made it resulted that for sustainable economic functioning of the locality several measures should be carried out. The extent of the measures should be appropriate in order not to disturb sustainable maintenance of social and ecological aspects.
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Nagy, Andras B. "Water Management Strategies In An Engineered Neotropical Landscape." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1343051764.
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Holmes, Jay Cuthbert. "Continuous reservoir simulation incorporating uncertainty quantification and real-time data." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1179.
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Pohl, Reinhard, and Antje Bornschein. "A management system to optimize reservoir control in the case of floods." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-160683.
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Many multipurpose reservoirs are situated in the low mountain range of Germany. Most of them are necessary for drinking water supply and flood protection as well. Other utilizations are recreation, water power and the downstream low water regulation during dry seasons. The operation rules of the reser-voirs have to be optimized to meet the different requirements of use. One tool within this framework is a management system for river basins including all reservoirs and their specific operation rules affecting the downstream reaches.
As an optimization objective for instance the minimization of inundation risks can be defined. In this case the risk can be defined as hydraulic and hydrologic safety of the reservoir itself and the risk due to inundation and damaging in the downstream regions. Considering the European Water Framework Directive the ecological aspect of reservoir management is one more point in the optimization process. To es-tablish a pilot project the software TALSIM will be applied to river catchments in the ore mountains (Saxony).
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Salami, Yunus. "Risk Management in Reservoir Operations in the Context of Undefined Competitive Consumption." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5478.
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Dams and reservoirs with multiple purposes require effective management to fully realize their purposes and maximize efficiency. For instance, a reservoir intended mainly for the purposes of flood control and hydropower generation may result in a system with primary objectives that conflict with each other. This is because higher hydraulic heads are required to achieve the hydropower generation objective while relatively lower reservoir levels are required to fulfill flood control objectives. Protracted imbalances between these two could increase the susceptibility of the system to risks of water shortage or flood, depending on inflow volumes and operational policy effectiveness. The magnitudes of these risks can become even more pronounced when upstream use of the river is unregulated and uncoordinated so that upstream consumptions and releases are arbitrary. As a result, safe operational practices and risk management alternatives must be structured after an improved understanding of historical and anticipated inflows, actual and speculative upstream uses, and the overall hydrology of catchments upstream of the reservoir. One of such systems with an almost yearly occurrence of floods and shortages due to both natural and anthropogenic factors is the dual reservoir system of Kainji and Jebba in Nigeria. To analyze and manage these risks, a methodology that combines a stochastic and deterministic approach was employed. Using methods outlined by Box and Jenkins (1976), autoregressive integrated moving average (ARIMA) models were developed for forecasting Niger river inflows at Kainji reservoir based on twenty-seven-year-long historical inflow data (1970-1996). These were then validated using seven-year inflow records (1997-2003). The model with the best correlation was a seasonal multiplicative ARIMA (2,1,1)x(2,1,2)12 model. Supplementary validation of this model was done with discharge rating curves developed for the inlet of the reservoir using in situ inflows and satellite altimetry data. By comparing net inflow volumes with storage deficit, flood and shortage risk factors at the reservoir were determined based on (a) actual inflows, (b) forecasted inflows (up to 2015), and (c) simulated scenarios depicting undefined competitive upstream consumption. Calculated high-risk years matched actual flood years again suggesting the reliability of the model. Monte Carlo simulations were then used to prescribe safe outflows and storage allocations in order to reduce futuristic risk factors. The theoretical safety levels achieved indicated risk factors below threshold values and showed that this methodology is a powerful tool for estimating and managing flood and shortage risks in reservoirs with undefined competitive upstream consumption.Ph.D.
Doctorate
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Civil Engineering
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Pohl, Reinhard, and Antje Bornschein. "A management system to optimize reservoir control in the case of floods." Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A28536.
Full textAbstract:
Many multipurpose reservoirs are situated in the low mountain range of Germany. Most of them are necessary for drinking water supply and flood protection as well. Other utilizations are recreation, water power and the downstream low water regulation during dry seasons. The operation rules of the reser-voirs have to be optimized to meet the different requirements of use. One tool within this framework is a management system for river basins including all reservoirs and their specific operation rules affecting the downstream reaches.
As an optimization objective for instance the minimization of inundation risks can be defined. In this case the risk can be defined as hydraulic and hydrologic safety of the reservoir itself and the risk due to inundation and damaging in the downstream regions. Considering the European Water Framework Directive the ecological aspect of reservoir management is one more point in the optimization process. To es-tablish a pilot project the software TALSIM will be applied to river catchments in the ore mountains (Saxony).
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Foster, Carole A. "Benthic macroinvertebrates in Uvas Creek, California, downstream of a reservoir." Thesis, San Jose State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1583489.
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I sampled macroinvertebrates in May, July, and October 2008 in Uvas Creek, a reservoir-regulated stream in south Santa Clara County, California, to assess what factors (including canopy closure, turbidity, and stream flow) downstream of the reservoir were related to food availability for rearing juvenile Steelhead (Oncorhynchus mykiss). I found benthic and drifting macroinvertebrate biomass was considerably greater during most months in the more open-canopied two sites in the downstream reach as compared to the densely shaded, more turbid and silty two sites in the upstream reach. Abundance of important drifting aquatic invertebrates in May (chironomids, simuliids, and baetids) was proportional to benthic abundance, but large hydropsychids were relatively scarce in the drift. Terrestrial drift abundance correlated with canopy density, but differences were small compared to the substantial increase in aquatic drift in sunnier sites. Thinning of the canopy at select locations and reduction of sediment input to Uvas Creek and its tributaries due to vineyard and other operations could increase benthic macroinvertebrate productivity in the upstream reach, which would increase food availability for rearing juvenile Steelhead.
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Scott, Robert Nigel. "Algal and related biological studies of reservoirs in South Wales with reference to management of water treatment systems." Thesis, Cardiff University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238187.
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Krueger, Kathryn Marie. "Metal fluxes across the sediment water interface in a drinking water reservoir." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/90297.
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Elevated concentrations of iron (Fe) and manganese (Mn) in drinking water degrade water quality by affecting taste, odor, and color. Under oxic conditions (dissolved oxygen (DO) >2 mg/L), Fe and Mn are rarely present in soluble form in natural waters, as they occur as insoluble, oxidized minerals in sediments. However, the development of low DO concentrations in the bottom waters of some lakes and drinking water reservoirs during thermal stratification can lead to the reduction of oxidized, insoluble Fe and Mn in sediments to soluble forms, which are then released into the water column. In response, many water utilities have installed oxygenation systems to control metal concentrations in situ in drinking water reservoirs. However, previous research has found anoxic (DO < 0.5 mg/L) conditions still develop within sediments, even with operational oxygenation systems, allowing for the reduction and release of soluble Fe and Mn into the water column.
To examine the drivers of metal release from sediments into the water column, I conducted sediment flux chamber experiments to directly quantify Fe and Mn fluxes at the sediment-water interface of a small, eutrophic drinking water reservoir (Falling Creek Reservoir, Vinton, VA). The experiments were conducted twice during the 2018 summer stratification period (April 24 – October 21). Using the flux chambers, I measured total and soluble Fe and Mn concentrations under changing oxygen conditions over 10-day periods to calculate fluxes. Throughout the experiments, I monitored DO, oxidation-reduction potential (ORP), temperature, and pH. In addition to the direct measurements, I also estimated metal fluxes using a mass balance method, which relies on measurements of metal inputs and outputs into the bottom waters of the reservoir.
Overall, our results showed that fluxes are highly variable during the stratification period, with some periods having positive fluxes (release of metals from sediment to the water column) and some with negative fluxes (return of metals from the water column to sediment). The metal fluxes are highly sensitive to redox conditions in the water column, sediment-water interface and sediments.
Metal fluxes measured using the chambers are 91-105% higher than those estimated using the mass balance method. This difference supports result of previous work that the flux chamber method likely provides maximum values of metal fluxes as the isolated chamber water does not allow for mixing with the bottom waters. In contrast, because the mass balance method relies on water column data, results are affected by mixing and biogeochemical reactions that can remove metals from the water column; thus, flux estimates using this method likely reflect minimum values. However, when used together, these two methods provide a useful tool for constraining metal fluxes under different redox conditions and highlight the importance of measuring ORP in addition to DO. The results of this study can be used by water utilities to improve the effectiveness of engineered oxygenation systems and water quality management practices related to iron and manganese.Master of Science
In many drinking water reservoirs, elevated concentrations of metals, such as iron (Fe) and manganese (Mn), pose a challenging water quality problem. Elevated metal concentrations affect taste, color, and odor in drinking water and can be expensive to treat for. The presence of Fe and Mn in water is influenced by the oxygen concentrations in the water. When oxygen levels in the water are high, Fe and Mn are not soluble in water. However, when the oxygen levels in water are low, Fe and Mn can be released from soils, sediments and rocks into water and can thus pose a concern for drinking water quality. Many water utilities have installed systems to increase oxygen concentrations in drinking water reservoirs with the goal of maintaining low levels of metals in water supplies. However, previous research has shown that even when oxygenation systems are operational, Fe and Mn can still be released into water from the reservoir’s bottom sediments. To examine the factors that contribute to the release of metals from the sediments into the water column, I measured the rate of release of Fe and Mn from the sediments into the water column at a local drinking water reservoir (Falling Creek Reservoir, Vinton, VA). I conducted the experiments twice during summer 2018 using chambers that isolated the water immediately above the sediments. During the experiments, I monitored how Fe and Mn concentrations changed over time under different oxygen conditions. In addition to the measurements, I also used a mass balance method using water column data to estimate the metal release. Overall, results showed that release rates are highly variable during the summer months, with some periods having positive rates (releasing metals from sediments into the water column) and some with negative rates (returning metals from the water column to sediment). The metal release rate are highly sensitive to oxygen conditions in the water column, at the sediment-water interface and in the sediments. When used together, these two methods provide a useful tool for constraining metal release rates under different oxygen conditions. This research will help drinking water plant managers to improve the effectiveness of oxygenation systems and water quality management practices related to Fe and Mn. Additionally, this research will help improve the water quality for residents and can be applied to other lakes and reservoirs where metal concentrations are elevated.
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Rivera, Dario Fernando. "Identifying ecological factors affecting populations of reservoir hosts of leptospirosis : implications for management /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18913.pdf.
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Hassane, Tharwat Fawzi Ragheb. "The application of streamline reservoir simulation calculations to the management of oilfield scale." Thesis, Heriot-Watt University, 2013. http://hdl.handle.net/10399/2707.
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Inorganic scale may precipitate in oilfield systems, down hole in the reservoir, in the production flow tubing, and in surface facilities, as a consequence of thermodynamic changes that affect the flowing brines. These changes may be induced by temperature or pressure changes, or by mixing of incompatible brines. While much work has been performed to study the effect of thermodynamic changes such as pressure decrease or temperature increase on scale precipitation, it is only recently that a body of work has been developed on the impact that the dynamics of brine mixing in the reservoir has on scale precipitation in situ. Much of this work has been conducted using finite difference simulators, which are handicapped with regard to these calculations in that numerical dispersion effects can be orders of magnitude greater than physical dispersion. The introduction of chemical reaction calculations into streamline simulation models presents a very significant opportunity for improving the accuracy of such calculations. While numerical dispersion effects for immiscible calculations (eg water displacing oil) can be countered by pseudoisation of the relative permeability functions, in finite difference models it is difficult to control numerical dispersion for miscible displacements e.g. seawater (with a Sulphate concentration) displacing formation water (with a Barium concentration), which may lead to scaling in the reservoir (Barium Sulphate precipitation). Streamline simulation reduces the numerical errors for both miscible and immiscible displacement, thus making the scaling calculations much more accurate. The objective of this PhD project was to study the application of a streamline simulator, which has the appropriate chemistry modeling capabilities, to realistic reservoir scenarios. The project consisted of two stages: 1) Study of synthetic systems to identify the impact of brine mixing in simple scenarios (eg single layer and multi-layer quarter five spot patterns) 2) Application of the technique to full field reservoir systems to improve the capability of making scale management decision during the project Front End Engineering and Design (FEED) phase. The calculations performed demonstrate where, and under what conditions, scale precipitation takes place in situ in the reservoir, and what the resulting impact on the chemical composition of the produced brine will be. This information is key in the planning of the management of oilfield scale.
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Moran, Leah L. K. "Ecosystem Impacts and Space Use of Double-Crested Cormorants in a Southeastern Reservoir System." Thesis, Mississippi State University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10841105.
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Double-crested Cormorants are expanding their breeding range to historic wintering and migratory regions, such as Guntersville Reservoir in Alabama. This study lends insight into how cormorants breeding in a temperate ecosystem impact plants, trees, soil and bird communities as well as home range and movement of cormorants during the breeding season and whether they reside on this reservoir year-round. Results suggest that breeding cormorants have a negative impact on this ecosystem and do not move far from colony sites. Stable isotopes from cormorants and prey fish suggest that cormorants are migrating from this system after breeding, potentially to a marine source. This study corroborates past studies of negative impacts of cormorant colonies, and provides novel results of how southeastern cormorants use and move on Guntersville Reservoir. This thesis can provide biologists information on how best to control populations and mitigate impacts on this and other similar southeastern systems.
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Lin, Paul Hong-Yi. "Data quality enhancement in oil reservoir operations : an application of IPMAP." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/76569.
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Thesis (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 70-71).
This thesis presents a study of data quality enhancement opportunities in upstream oil and gas industry. Information Product MAP (IPMAP) methodology is used in reservoir pressure and reservoir simulation data, to propose data quality recommendations for the company under study. In particular, a new 4-step methodology for examining data quality for reservoir pressure management systems is proposed: 1. Trace the data flow and draw the IPMAP; 2. Highlight the cross-system and organizational boundaries; 3. Select data quality analytical questions based on data quality literature review; 4. Apply the analytical questions at each boundary and document the results. This original methodology is applied to the three management systems to collect a pressure survey: using a spreadsheet, a standardized database and an automated database. IPMAPs are drawn to each of these three systems and cross-system and organizational boundaries are highlighted. Next, data quality systematic questions are applied. As a result, three data quality problems are identified and documented: well identifier number, well bore data and reservoir datum. The second experiment investigates the data quality issues in the scope of reservoir simulation and forecasting. A high-level IPMAP and a process flow on reservoir simulation and forecasting are generated. The next section further elaborates on the first high level process flow and drills into the process flow for simulation. The analytical data quality questions are raised to the second simulation process flow and limited findings were documented. This thesis concludes with lessons learned and directions for future research.
by Paul Hong-Yi Lin.
S.M.in Engineering and Management
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Cabral, Samuellson Lopes. "Time interval of maximum predictability in coupled climate and hydrological models for reservoir management." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12795.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorThis work seeks to integrate climatic, hydrologic, and reservoir operation models in order to optimize available water volume in the Brazilian Northeast. The global ECHAM 4.5 climate model was used to feed the RAMS regional climate model for the Alto Jaguaribe hydrographic basin. Resulting precipitation values were calibrated by the probability density function (PDF) correction of simulated data compared with average daily precipitation data using the Thiessen method for the period 1979-2009. The Heidke Skill Score (HSS) was used to evaluate model performance in the Maximum Predictable Time Interval (ITEMP) of the atmospheric model. These PDF-corrected precipitation data, both observed and RAMS-simulated, were inserted in the hydrologic Soil Moisture Account (SMA) model from the Hydrologic Engineering Center â Hydrologic Modeling System (HEC-HMS) to determine modeled flows. These flows were then compared with median observed flows. To calibrate and validate the SMA, an iterative method was used to minimize percentage error of volume. The data returned by this cascade model was applied to assisting policy-makers determine water releases from the OrÃs reservoir. Three different scenarios were compared, the first based on observed flows, the second flows simulated by SMA with observed precipitation, and the third by flows simulated by SMA driven by the RAMS-PDF precipitation data. The RAMS model showed optimal efficiency in precipitation prediction on a 30 to 45 day interval, with HSS values of 0.56. The SMA model showed satisfactory performance with Nash-Sutcliffe values of 0.89 in the calibration phase and 0.67 in the validation phase, demonstrating its capacity to assist hydrological modeling in the semi-arid. This cascade model showed potential in accurately representing median inflows for the reservoir and as such can be used as a hydrologic tool, assisting reservoir operation decisions to meet the regionâs demand. Keywords: Soil Moisture Account; hydrologic
O presente trabalho visa o acoplamento de modelo atmosfÃrico, hidrolÃgico e de operaÃÃo de reservatÃrio com vistas à otimizaÃÃo da liberaÃÃo de Ãguas no semiÃrido do nordeste brasileiro. O modelo atmosfÃrico regional RAMS foi forÃado pelo modelo atmosfÃrico global ECHAM 4.5, na bacia hidrogrÃfica do Alto Jaguaribe, e em seguida, aplicada a correÃÃo probability density function (PDF) nos dados simulados e comparado com dados diÃrio de precipitaÃÃo mÃdia observada pelo mÃtodo de Thiessen no perÃodo de 1979-2009. Foi utilizando o Heidke Skill Score (HSS) como mÃtrica principal para avaliar o desempenho da previsÃo em busca do Intervalo de Tempo de MÃxima Previsibilidade (ITEMP) do modelo atmosfÃrico. Os dados de precipitaÃÃes observados e simulados pelo RAMS com correÃÃes PDFs foram inseridos no modelo hidrolÃgico Soil Moisture Account (SMA) do Hydrologic Engineering Center - Hydrologic Modeling System (HEC-HMS), e comparado com as vazÃes mÃdias observadas. Para a calibraÃÃo e validaÃÃo do SMA, foi realizado um mÃtodo interativo para minimizar uma funÃÃo objetivo, com base no erro percentual do volume. Por fim foi desenvolvido e avaliado um modelo de cascata a fim de comparar as decisÃes operacionais de liberaÃÃo do reservatÃrio OrÃs com diferentes cenÃrios com base nas vazÃes observadas, vazÃes simuladas pelo SMA com a precipitaÃÃo observada e vazÃes simuladas pelo SMA forÃada com o RAMS-PDF. O modelo RAMS mostrou melhor eficiÃncia na previsÃo da precipitaÃÃo no intervalo de 30 a 45 dias, com valores de HSS = 0,56. O modelo SMA mostrou desempenho satisfatÃrio com valores de Nash-Sutcliffe de 0,89 na fase de calibraÃÃo e 0,67 na fase de validaÃÃo, mostrando ser uma nova alternativa de utilizaÃÃo de modelo hidrolÃgico no semiÃrido. O modelo de cascata mostrou potencial em representar bem as afluÃncias mÃdias do reservatÃrio, podendo tornar uma ferramenta hidrolÃgica, auxiliando as decisÃes de operaÃÃo dos reservatÃrios, atendendo as demandas da regiÃo.
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Rains, Mark Cable. "Surface and ground-water origins and interactions and vegetation distributions in riverine and reservoir-fringe systems : a case study in support of reservoir management efforts /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Ammah, Anass Nii-Armah. "Applying Time-Lapse Seismic Inversion In Reservoir Management: A Case Study Of The Norne Field." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18611.
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Time-lapse seismic inversion approach to reservoir management has proven to be a vital tool in the industry today because of its effectiveness in tracking the movement of fluid front within the reservoir as well as identifying isolated bypassed accumulations. A base (2001) and three monitor (2003, 2004 and 2006) seismic surveys from the Norne field were inverted during this research. Water and gas have been injected into the reservoir to maintain the initial pressure within the field. These seismic surveys were analyzed for time-lapse impedance changes due to the differences in the produced hydrocarbons and the injected fluids. Check-shot corrected well data as well as interpreted horizons were integrated in the inversion process. Two independent wavelets were extracted from base and monitor surveys and combined to form an all-encompassing frequency and amplitude wavelet. The base and monitors were jointly inverted. This is because of the reduction in inconsistencies that are associated with independent inversions of surveys and the production related changes expected in time-lapse inverted seismic data.The results of the inversion show the impedance difference across the field for the various monitor surveys. Areas surrounding producer wells show slight changes in impedance while great impedance difference are observed around injector wells. A statistical analysis of the inversion results also shows steady increase in impedance across the field for the subsequent monitors. Structural and stratigraphic interpretation of the time-lapse inverted data also confirmed the sealing properties of some formations. This sealing property supported the impedance changes within the field. Fault interpretations as well as its sealing and non-sealing properties were inferred from the impedance differences across various discontinuities. Time-lapse acoustic impedance inversion of the Norne post-stack seismic data has revealed the impacts of production, dynamic fluid changes across main identified geologic structures, fluid front migration, fluid communication across structures and segments and other identified stratigraphic elements.
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Green, Michael. "Coping with climate change uncertainty for adaptation planning for local water management." Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/8649.
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Environmental management is plagued with uncertainty, despite this, little attention has until recently been given to the sensitivity of management decisions to uncertain environmental projections. Assuming that the future climate is stationary is no longer considered valid, nor is using a single or small number of potentially incorrect projections to inform decisions. Instead, it is recommended that decision makers make use of increasingly available probabilistic projections of future climate change, such as those from perturbed physics ensembles like United Kingdom Climate Projections 2009 (UKCP09), to gauge the severity and extent of future impacts and ultimately prepare more robust solutions. Two case studies focussing on contrasting aspects of local water management; namely irrigation demand and urban drainage management, were used to evaluate current approaches and develop recommendations and improved methods of using probabilistic projections to support decision making for climate change adaptation. A quantitative understanding of the impact of uncertainty to decision making for climate change adaptation was obtained from a literature review; followed by a comparison of using (1) the low medium and high emission scenarios, (2) 10,000 sample ensemble and 11 Spatially Coherent Projections (11SCP), (3) deterministic and probabilistic climate change projections, (4) the complete probabilistic dataset and sub-samples of it using different sampling techniques, (5) the change factor (or delta change) and stochastic (or UKCP09 weather generator) downscaling techniques and (6) different decision criteria using two contrasting case studies at three UK sites. This research provides an insight into the impact of different sources of uncertainty to real-world adaptation and explores whether having access to more data and a greater appreciation of uncertainty alters the way we make decisions. The impact of the “envelope of uncertainty” to decision making is explored in order to identify those factors and decisions that have the greatest impact on what we perceive to be the “best” solution. An improved novel decision criterion for use with probabilistic projections for adaptation planning is presented and tested using simplified real-world case studies to establish whether it provides a more attractive tool for decision makers compared to the current decision criteria which have been advocated for adaptation planning. This criterion explicitly incorporates the unique risk appetite of the individual into the decision making process, acknowledging that this source of uncertainty and not necessarily the climate change projections, had the greatest impact on the decisions considered by this research. This research found the differences between emission scenarios, projection datasets, sub-sampling approaches and downscaling techniques, each contributing a different source of uncertainty, tended to be small except where the decision maker already exhibited an extremely risk seeking or risk adverse appetite. This research raises a number of interesting questions about the “decision significance” of uncertainty through the systematic analysis of several different sources of uncertainty on two contrasting local water management case studies. Through this research, decision makers are encouraged to take a more active role in the climate change adaptation debate, undertaking their own analysis with the support of the scientific community in order to highlight those uncertainties that have significant implications for real world decisions and thereby help direct future efforts to characterise and reduce them. The findings of this research are of interest to planners, engineers, stakeholders and adaptation planning generally.
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Bewer, Robert. "Recreational ecosystem service benefits from the Chestermere Lake Reservoir : value for day use non-resident visitors." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Geography, c2012, 2012. http://hdl.handle.net/10133/3314.
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Irrigation infrastructure provides many ecosystem service (ES) benefits that enhance the well-being of Albertans and is central to economic activity in southern Alberta. Management of irrigation infrastructure and water resources is becoming increasingly challenging as Alberta’s population and economy grows. Past water allocation decisions have not generally considered the need of ecosystems leading to declining ecosystem health, and changes to provision of ES benefits in Alberta. The goals of current Alberta government policy include changing how water and land is managed to ensure that ecosystem health and ES provision is maintained.
The research in this thesis concentrates on establishing the value of recreational ES benefits provided by the Chestermere Lake Reservoir, and obtaining information on the spatial aspects and visitor characteristics. A mixed method approach is used combining a qualitative discussion with a quantitative analysis using a geographic information system (GIS) and the travel cost method (TCM). The selection of the mixed method and combined GIS-TCM approach was based on past success in previous studies. The findings reveal a substantial value for recreational ES benefits provided by the Chestermere Lake Reservoir occurring within a limited area similar to other studies of recreational benefits from reservoirs. The findings of this research provide information for decisions makers, water infrastructure managers, and water transfer participants when assessing the impact of planned actions. Further research is recommended to build upon the findings of this study and further expand the available information on ES benefits to include all ES provided by southern Alberta.x, 125 leaves : col. ill. ; 29 cm
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Benneyworth, Laura Mahoney. "Distribution of Trace Elements in Cumberland River Basin Reservoir Sediments." TopSCHOLAR®, 2011. http://digitalcommons.wku.edu/theses/1113.
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The U.S. Army Corps of Engineers, Nashville District, maintains ten reservoirs in the Cumberland River Basin in Kentucky and Tennessee, and has been monitoring sediment chemistry in the reservoirs since 1994. The purpose of this study is to evaluate the sediment data collected from the reservoirs from 1994 to 2010 to determine if there are any spatial patterns of the trace elements: arsenic, beryllium, cadmium, chromium, copper, lead, mercury, nickel, and zinc. The results indicated that trace element levels were consistent with national baseline concentrations measured by the U.S. Geological Survey. Center Hill reservoir had the greatest number of trace element concentrations (all except cadmium) that were significantly higher when compared to all other reservoirs. The degree of urbanization in the reservoir basins was based on population density from the 2000 Census and the percentage of developed land using the 2006 national land cover dataset. Aquatic toxicity values were used as a measure of sediment quality. The reservoirs with the worst aquatic toxicity rankings were not the most urban, instead they were the reservoirs with the longest retention times. Therefore, it may be concluded that retention time has a larger effect on Cumberland River Basin sediment concentrations than the type of land use or the degree of urbanization. The results also indicate that it may be prudent to include an evaluation of quality based on aquatic toxicity when monitoring sediment quality, and that when reservoirs are the subject of sediment quality assessments, the consideration of the physical properties of the reservoir, especially the retention time, is essential for a comprehensive evaluation. This may also imply that sediment quality in reservoirs may effectively be regulated by water resource management techniques at the reservoirs that affect retention time.
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McCollor, Douglas. "Improving hydrometeorologic numerical weather prediction forecast value via bias correction and ensemble analysis." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/979.
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This dissertation describes research designed to enhance hydrometeorological forecasts. The objective of the research is to deliver an optimal methodology to produce reliable, skillful and economically valuable probabilistic temperature and precipitation forecasts.
Weather plays a dominant role for energy companies relying on forecasts of watershed precipitation and temperature to drive reservoir models, and forecasts of temperatures to meet energy demand requirements. Extraordinary precipitation events and temperature extremes involve consequential water- and power-management decisions.
This research compared weighted-average, recursive, and model output statistics bias-correction methods and determined optimal window-length to calibrate temperature and precipitation forecasts. The research evaluated seven different methods for daily maximum and minimum temperature forecasts, and three different methods for daily quantitative precipitation forecasts, within a region of complex terrain in southwestern British Columbia, Canada.
This research then examined ensemble prediction system design by assessing a three-model suite of multi-resolution limited area mesoscale models. The research employed two different economic models to investigate the ensemble design that produced the highest-quality, most valuable forecasts.
The best post-processing methods for temperature forecasts included moving-weighted average methods and a Kalman filter method. The optimal window-length proved to be 14 days. The best post-processing methods for achieving mass balance in quantitative precipitation forecasts were a moving-average method and the best easy systematic estimator method. The optimal window-length for moving-average quantitative precipitation forecasts was 40 days. The best ensemble configuration incorporated all resolution members from all three models.
A cost/loss model adapted specifically for the hydro-electric energy sector indicated that operators managing rainfall-dominated, high-head reservoirs should lower their reservoir with relatively low probabilities of forecast precipitation. A reservoir-operation model based on decision theory and variable energy pricing showed that applying an ensemble-average or full-ensemble precipitation forecast provided a much greater profit than using only a single deterministic high-resolution forecast.
Finally, a bias-corrected super-ensemble prediction system was designed to produce probabilistic temperature forecasts for ten cities in western North America. The system exhibited skill and value nine days into the future when using the ensemble average, and 12 days into the future when employing the full ensemble forecast.
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Гасимов, К. А. "Задача управления режимами стока реки с водохранилищами в условиях полноводья и мелководья." Thesis, Сумский государственный университет, 2016. http://essuir.sumdu.edu.ua/handle/123456789/46602.
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Авторами разработана задача оптимального управления стоком крупной реки с тремя последовательно расположенными водохранилищами, в каждом участке которого имеется одна притекающая речка и один отводящий канал.
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Dillon, Rebecca. "Re-evaluation of north-temperate reservoir food web interactions and their assessment." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1594472755977476.
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Lewis, David M. "Surface mixers for destratification and management of Anabaena circinalis / by David Milton Lewis." 2004. http://hdl.handle.net/2440/22047.
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"March 2004"Bibliography: leaves 221-234.
xxiv, 249 leaves : ill. (some col.), maps, photos (col.) ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
This research is part of the SA Water and Cooperative Centre for Water Quality and Treatment project entitled Destratification for control of phyloplankton. The major objective of this project was to assess a novel method of destratification and control of cyanobacteria, in particular Anabaena circinalis Rabenh. ex Born. et Flah, with the use of raft-mounted mechanical surface mixers with draft-tubes.
Thesis (Ph.D.)--University of Adelaide, School of Civil and Environmental Engineering, 2004
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Lewis, David Milton. "Surface mixers for destratification and management of Anabaena circinalis / by David Milton Lewis." Thesis, 2004. http://hdl.handle.net/2440/22047.
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"March 2004"Bibliography: leaves 221-234.
xxiv, 249 leaves : ill. (some col.), maps, photos (col.) ; 30 cm.
This research is part of the SA Water and Cooperative Centre for Water Quality and Treatment project entitled Destratification for control of phyloplankton. The major objective of this project was to assess a novel method of destratification and control of cyanobacteria, in particular Anabaena circinalis Rabenh. ex Born. et Flah, with the use of raft-mounted mechanical surface mixers with draft-tubes.
Thesis (Ph.D.)--University of Adelaide, School of Civil and Environmental Engineering, 2004
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YU, ZIH-EN, and 于子恩. "Study on the sustainable management strategy planning of reservoir catchment area—Bao-Shan Reservoir and Yong-He-Shan Reservoir." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/xta4pp.
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碩士逢甲大學
水利工程與資源保育學系
107
This study is aimed at the management strategy planning of the im-portant reservoirs. The study area is the Bao-Shan Reservoir of Hsinchu and the Yong-He-Shan Reservoir of Miaoli. Both of them are off-stream reservoirs. Therefore, the purpose of this study is to assess the pollution sources of the Reservoir and to analyze the pollution hotspots in the wa-tershed. And this study use Storm Water Management Model (SWMM) as the model to simulate the total phosphorus pollution production in the watershed. Moreover, the results of hotspot analysis show that the subwatersheds have more pollution yield per year, since these subwa-tersheds have larger area. The pollution hotspots are located in the subwatersheds. Therefore, this study applies theVollenweider model to estimate the required pollurion removal rate. The current situation of the two reservoirs is different. If we want to improve water quality can be significant references for the relevant management agency. Finally, this study analyzes the impact of climate change on the flow and water quality based on TCCIP data. The scenario of the dynamical downscaling is dominated by storm events, while scenario of the statistical downscaling is the long-term rainfall scenario. It can be seen from the research results that the rainfall situation at the end of the century is higher than the near future, which affects the flow and water quality. About 89% of the water source in Bao-Shan Reservoir is led to Shang-Ping River. The point source and non-point source pollution in the reservoir area are 56% and 44% respectively. The Shang-Ping wa-tershed is dominated by non-point source pollution, accounting for about 90% of the total. The results indicate that about 24% of TP needs to be reduced to improve the reservoir water quality and to solve the eutrophication problems. The analysis and discussion in this study can be significant references for the relevant management agency of theBao-Shang Reservoir. And 90% of the Yong-He-Shan Reservoir comes from the Tian-Mei watershed. The point source and non-point source pollution of the Yongheshan Reservoir account for 62% and 38% respectively. The non-point source pollution of the Tian-Mei watershed also accounts for 90%. The Yong-He-Shan Reservoir is in a stable and nutrient state, which can reduce the amount of pollution by about 20% to make the water quality to reach a better state.
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Lin, Chia-Yu, and 林家瑜. "Dynamic Water Resource Distribution Management in Reservoir Systems." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/14418114500827756936.
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碩士國立雲林科技大學
資訊管理研究所
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Water is one of most important resources in human needs. In Taiwan, rainfall is abundant. However, the mountains are steep, and rainfall is unevenly distributed in different seasons. Both make it difficult to keep water in an effective manner. Reservoirs and waterways play a vital role in regulating water in space and time for various needs, such as daily life, public, industry, agriculture, and so on. The effectiveness of each need is quite different. With limited water, it is rather significant to allocate water for maximum effectiveness. On the other hand, the loss of water through soils, rivers, waterways, pollution makes it difficult to optimize the management of water. The objective of this study is to construct a self-organizing learning computer simulation model that investigates management of reservoirs and waterways through evolutionary learning algorithms. The experimental results show that the system shows better learning capability when rainfall is evenly distributed. Increasing the number of waterways interconnected with reservoirs can increase the effectiveness of the system. However, too great an increase in the number would provide little help, and the learning speed of the system slows down significantly.