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Dissertations / Theses on the topic 'Operational hydrology'

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1

Tilford, Kevin A. "Weather radar data for operational hydrology." Thesis, University of Salford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315383.

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2

Zarekarizi, Mahkameh. "Ensemble Data Assimilation for Flood Forecasting in Operational Settings: from Noah-MP to WRF-Hydro and the National Water Model." PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4651.

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The National Water Center (NWC) started using the National Water Model (NWM) in 2016. The NWM delivers state-of-the-science hydrologic forecasts in the nation. The NWM aims at operationally forecasting streamflow in more than 2,000,000 river reaches while currently river forecasts are issued for 4,000. The NWM is a specific configuration of the community WRF-Hydro Land Surface Model (LSM) which has recently been introduced to the hydrologic community. The WRF-Hydro model, itself, uses another newly-developed LSM called Noah-MP as the core hydrologic model. In WRF-Hydro, Noah-MP results (such as soil moisture and runoff) are passed to routing modules. Riverine water level and discharge, among other variables, are outputted by WRF-Hydro. The NWM, WRF-Hydro, and Noah-MP have recently been developed and more research for operational accuracy is required on these models. The overarching goal in this dissertation is improving the ability of these three models in simulating and forecasting hydrological variables such as streamflow and soil moisture. Therefore, data assimilation (DA) is implemented on these models throughout this dissertation. State-of-the art DA is a procedure to integrate observations obtained from in situ gages or remotely sensed products with model output in order to improve the model forecast. In the first chapter, remotely sensed satellite soil moisture data are assimilated into the Noah-MP model in order to improve the model simulations. The performances of two DA techniques are evaluated and compared in this chapter. To tackle the computational burden of DA, Massage Passing Interface protocols are used to augment the computational power. Successful implementation of this algorithm is demonstrated to simulate soil moisture during the Colorado flood of 2013. In the second chapter, the focus is on the WRF-Hydro model. Similarly, the ability of DA techniques in improving the performance of WRF-Hydro in simulating soil moisture and streamflow is investigated. The results of chapter 2 show that the assimilation of soil moisture can significantly improve the performance of WRF-Hydro. The improvement can reach 58% depending on the study location. Also, assimilation of USGS streamflow observations can improve the performance up to 25%. It was also observed that soil moisture assimilation does not affect streamflow. Similarly, streamflow assimilation does not improve soil moisture. Therefore, joint assimilation of soil moisture and streamflow using multivariate DA is suggested. Finally, in chapter 3, the uncertainties associated with flood forecasting are studied. Currently, the only uncertainty source that is taken into account is the meteorological forcings uncertainty. However, the results of the third chapter show that the initial condition uncertainty associated with the land state at the time of forecast is an important factor that has been overlooked in practice. The initial condition uncertainty is quantified using the DA. USGS streamflow observations are assimilated into the WRF-Hydro model for the past ten days before the forecasting date. The results show that short-range forecasts are significantly sensitive to the initial condition and its associated uncertainty. It is shown that quantification of this uncertainty can improve the forecasts by approximately 80%. The findings of this dissertation highlight the importance of DA to extract the information content from the observations and then incorporate this information into the land surface models. The findings could be beneficial for flood forecasting in research and operation.
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Gan, Tian. "Advancing Cyberinfrastructure for Collaborative Data Sharing and Modeling in Hydrology." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7618.

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Hydrologic research is increasingly data and computationally intensive, and often involves hydrologic model simulation and collaboration among researchers. With the development of cyberinfrastructure, researchers are able to improve the efficiency, impact, and effectiveness of their research by utilizing online data sharing and hydrologic modeling functionality. However, further efforts are still in need to improve the capability of cyberinfrastructure to serve the hydrologic science community. This dissertation first presents the evaluation of a physically based snowmelt model as an alternative to a temperature index model to improve operational water supply forecasts in the Colorado River Basin. Then it presents the design of the functionality to share multidimensional space-time data in the HydroShare hydrologic information system. It then describes a web application developed to facilitate input preparation and model execution of a snowmelt model and the storage of these results in HydroShare. The snowmelt model evaluation provided use cases to evaluate the cyberinfrastructure elements developed. This research explored a new approach to advance operational water supply forecasts and provided potential solutions for the challenges associated with the design and implementation of cyberinfrastructure for hydrologic data sharing and modeling.
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Adams, Thomas Edwin III. "The Use of Central Tendency Measures from an Operational Short Lead-time Hydrologic Ensemble Forecast System for Real-time Forecasts." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/83461.

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A principal factor contributing to hydrologic prediction uncertainty is modeling error intro- duced by the measurement and prediction of precipitation. The research presented demon- strates the necessity for using probabilistic methods to quantify hydrologic forecast uncer- tainty due to the magnitude of precipitation errors. Significant improvements have been made in precipitation estimation that have lead to greatly improved hydrologic simulations. However, advancements in the prediction of future precipitation have been marginal. This research shows that gains in forecasted precipitation accuracy have not significantly improved hydrologic forecasting accuracy. The use of forecasted precipitation, referred to as quantita- tive precipitation forecast (QPF), in hydrologic forecasting remains commonplace. Non-zero QPF is shown to improve hydrologic forecasts, but QPF duration should be limited to 6 to 12 hours for flood forecasting, particularly for fast responding watersheds. Probabilistic hydrologic forecasting captures hydrologic forecast error introduced by QPF for all forecast durations. However, public acceptance of probabilistic hydrologic forecasts is problematic. Central tendency measures from a probabilistic hydrologic forecast, such as the ensemble median or mean, have the appearance of a single-valued deterministic forecast. The research presented shows that hydrologic ensemble median and mean forecasts of river stage have smaller forecast errors than current operational methods with forecast lead-time beginning at 36-hours for fast response basins. Overall, hydrologic ensemble median and mean forecasts display smaller forecast error than current operational forecasts.<br>Ph. D.
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5

Power, Clare. "Use of satellite remote sensing of cloud and rainfall for selected operational applications in the fields of applied hydrology and food production." Thesis, University of Bristol, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329886.

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6

Zhu, Zhipeng. "Techniques to Evaluate the Modifier Process of National Weather Service Flood Forecasts." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1613752950288287.

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7

Smiley, Mark Andrew. "Hydrologic modeling for flood control detention basin design and operation." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186722.

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This dissertation presents a methodology for hydrologic modeling related to the design and operation of flood control detention basins. Prior to this document, a comprehensive, tractable methodology for detention basin hydrologic modeling did not exist. Furthermore, techniques used in the past have not always taken advantage of computer technology or recent advances in the field of hydrology. New and original methods are presented and are developed from personal experience, recent literature, and relevant courses at The University of Arizona. Chapters in this document include precipitation data analysis, detention basin stormwater inflow, detention basin sediment inflow, stored water losses through evaporation and infiltration, design issues, and operation under competing water use objectives. Engineering constraints and data availability are explicitly addressed throughout the methodology. The goal is to determine hydrologic variables for detention basin design such as active storage volume, spillway capacity, drain outlet capacity, and, additionally for some systems, the bypass channel capacity and side-weir threshold spill flow rate. In addition to providing an increased level of protection from flood damage, detention basins may also accommodate land use and water conservation objectives of urban society.
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8

Peng, Cheng-shuang 1963. "Dynamic operation of a reservoir system with discontinuous and short-term data." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282798.

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The objective of this study is to develop a practical mathematical model to determine optimal operating rules for the reservoir system of the West Branch Penobscot River in the State of Maine of the US. This system is composed of five major lakes and it has three objectives. The hydrological data are not available in winter in the upstream four lakes due to freeze and the length of flow data is less than 25 years. Dynamic programming (DP) has been used extensively for solving reservoir operation problems. One major drawback of DP for multiple reservoir operation is the "curse of dimensionality". Many variations of the original DP have been proposed to ease this problem, for example, incremental DP, discrete differential DP, differential DP, gradient DP, and spline DP. Instead of a DP approach, this study proposes using a nonlinear programming (NLP) approach to solve the multi-reservoir system. NLP has been developed extensively in the field of operations research but not yet widely used in reservoir operations. A distinct advantage of using an NLP model is that it can avoid the dimensionality problem because it solves directly the problem without discretizing the decision variables. To use the NLP approach, a real time operation model is specified at first. Then, a multivariate first-order autoregressive model is used to generate a large number of future inflow sequences. The MINOS software package is then used to optimize the problem with each inflow sequence. MINOS can be implemented seemly in the simulation process and can solve the problems without starting values of variables. The number of runs in a simulation is determined by a statistical model, which shows that 500 runs are sufficient. Finally, the expected values and standard deviations of decision variables are tabulated and the distributions of decision variables are plotted. The proposed real time operation model runs once every month. An information-updating scheme is embedded into the simulation and optimization models. For each month, the synthetic streamflows are updated to reflect the most recent hydrological conditions. Besides, the objective function and constraints can be modified if the situation of the system changes.
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9

Yapo, Patrice Ogou 1967. "A multiobjective global optimization algorithm with application to calibration of hydrologic models." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/290649.

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This dissertation presents a new multiple objective optimization algorithm that is capable of solving for the entire Pareto set in one single optimization run. The multi-objective complex evolution (MOCOM-UA) procedure is based on the following three concepts: (1) population, (2) rank-based selection, and (3) competitive evolution. In the MOCOM-UA algorithm, a population of candidate solutions is evolved in the feasible space to search for the Pareto set. Ranking of the population is accomplished through Pareto Ranking, where all points are successively placed on different Pareto fronts. Competitive evolution consists of selecting subsets of points (including all worst points in the population) based on their ranks and moving the worst points toward the Pareto set using the newly developed multi-objective simplex (MOSIM) procedure. Test analysis on the MOCOM-UA algorithm is accomplished on mathematical problems of increasing complexity and based on a bi-criterion measure of performance. The two performance criteria used are (1) efficiency, as measured by the ability of the algorithm to converge quickly and (2) effectiveness, as measured by the ability of the algorithm to locate the Pareto set. Comparison of the MOCOM-UA algorithm against three multi-objective genetic algorithms (MOGAs) favors the former. In a realistic application, the MOCOM-UA algorithm is used to calibrate the Soil Moisture Accounting model of the National Weather Service River Forecasting Systems (NWSRFS-SMA). Multi-objective calibration of this model is accomplished using two bi-criterion objective functions, namely the Daily Root Mean Square-Heteroscedastic Maximum Likelihood Estimator (DRMS, HMLE) and rising limb-falling limb (RISE, FALL) objective functions. These two multi-objective calibrations provide some interesting insights into the influence of different objectives in the location of final parameter values as well as limitations in the structure of the NWSRFS-SMA model.
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10

Minett, S. T. "The hydrogeology of parts of the Northumberland and Durham Coalfield related to opencast mining operations." Thesis, University of Newcastle Upon Tyne, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376314.

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11

Mounir, Adil. "Development of a Reservoir System Operation Model for Water Sustainability in the Yaqui River Basin." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1513880139368117.

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12

Guffey, Ross L. "EVALUATING THE EFFECTIVENESS OF WEEP BERM SYSTEMS FOR TREATING RUNOFF FROM A HORSE MUCK COMPOSTING OPERATION." UKnowledge, 2012. http://uknowledge.uky.edu/bae_etds/12.

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Two contour weep berms systems were designed and implemented to evaluate their performance at mitigating water quantity problems from a horse muck composting operation. The field-scale study focused on the hydrologic response of a standard contour weep berm and a modified contour weep berm. The modified contour weep berm incorporated a woodchip trench upgradient of a typical standard contour weep design. Monitoring occurred from July 2011 through spring 2012. Eight storm events produced measureable runoff for the standard contour weep berm; however, only five storm events produced measurable runoff for the modified contour weep berm. The largest storm event occurred on November 27, 2012 with rainfall depth of 49.0 mm. This storm event generated a total runoff volume of 183.1 m3 and 188.5 m3 for the standard and modified contour weep berms, respectively. All runoff produced from the storm events during the monitoring period was completely detained and infiltrated. No runoff was released from the horse muck composting facility through the passive dewatering system to down-gradient vegetative filter strips during the monitoring period.
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13

Pina, Fulano Jasson. "The value of hydrological information in multireservoir systems operation." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/28228.

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La gestion optimale d’un système hydroélectrique composé de plusieurs réservoirs est un problème multi-étapes complexe de prise de décision impliquant, entre autres, (i) un compromis entre les conséquences immédiates et futures d’une décision, (ii) des risques et des incertitudes importantes, et (iii) de multiple objectifs et contraintes opérationnelles. Elle est souvent formulée comme un problème d’optimisation, mais il n’existe pas, à ce jour, de technique de référence même si la programmation dynamique (DP) a été souvent utilisée. La formulation stochastique de DP (SDP) permet la prise en compte explicite de l’incertitude entourant les apports hydrologiques futurs. Différentes approches ont été développées pour incorporer des informations hydrologiques et climatiques autres que les apports. Ces études ont révélé un potentiel d’amélioration des politiques de gestion proposées par les formulations SDP. Cependant, ces formulations sont applicables aux systèmes de petites tailles en raison de la célèbre « malédiction de la dimensionnalité ». La programmation dynamique stochastique duale (SDDP) est une extension de SDP développée dans les années 90. Elle est l’une des rares solutions algorithmiques utilisées pour déterminer les politiques de gestion des systèmes hydroélectriques de grande taille. Dans SDDP, l’incertitude hydrologique est capturée à l’aide d’un modèle autorégressif avec corrélation spatiale des résidus. Ce modèle analytique permet d’obtenir certains des paramètres nécessaires à l’implémentation de la technique d’optimisation. En pratique, les apports hydrologiques peuvent être influencés par d’autres variables observables, telles que l’équivalent de neige en eau et / ou la température de la surface des océans. La prise en compte de ces variables, appelées variables exogènes, permet de mieux décrire les processus hydrologiques et donc d’améliorer les politiques de gestion des réservoirs. L’objectif principal de ce doctorat est d’évaluer la valeur économique des politiques de gestion proposées par SDDP et ce pour diverses informations hydro-climatiques. En partant d’un modèle SDDP dans lequel la modélisation hydrologique est limitée aux processus Makoviens, la première activité de recherche a consisté à augmenter l’ordre du modèle autorégressif et à adapter la formulation SDDP. La seconde activité fut dédiée à l’incorporation de différentes variables hydrologiques exogènes dans l’algorithme SDDP. Le système hydroélectrique de Rio Tinto (RT) situé dans le bassin du fleuve Saguenay-Lac-Saint-Jean fut utilisé comme cas d’étude. Étant donné que ce système n’est pas capable de produire la totalité de l’énergie demandée par les fonderies pour assurer pleinement la production d’aluminium, le modèle SDDP a été modifié de manière à considérer les décisions de gestion des contrats avec Hydro Québec. Le résultat final est un système d’aide à la décision pour la gestion d’un large portefeuille d’actifs physiques et financiers en utilisant diverses informations hydro-climatiques. Les résultats globaux révèlent les gains de production d’énergie auxquels les opérateurs peuvent s’attendre lorsque d’autres variables hydrologiques sont incluses dans le vecteur des variables d’état de SDDP.<br>The optimal operation of a multireservoir hydroelectric system is a complex, multistage, stochastic decision-making problem involving, among others, (i) a trade-off between immediate and future consequences of a decision, (ii) considerable risks and uncertainties, and (iii) multiple objectives and operational constraints. The reservoir operation problem is often formulated as an optimization problem but not a single optimization approach/algorithm exists. Dynamic programming (DP) has been the most popular optimization technique applied to solve the optimization problem. The stochastic formulation of DP (SDP) can be performed by explicitly considering streamflow uncertainty in the DP recursive equation. Different approaches to incorporate more hydrologic and climatic information have been developed and have revealed the potential to enhance SDP- derived policies. However, all these techniques are limited to small-scale systems due to the so-called curse of dimensionality. Stochastic Dual Dynamic Programming (SDDP), an extension of the traditional SDP developed in the 90ies, is one of the few algorithmic solutions used to determine the operating policies of large-scale hydropower systems. In SDDP the hydrologic uncertainty is captured through a multi-site periodic autoregressive model. This analytical linear model is required to derive some of the parameters needed to implement the optimization technique. In practice, reservoir inflows can be affected by other observable variables, such snow water equivalent and/or sea surface temperature. These variables, called exogenous variables, can better describe the hydrologic processes, and therefore enhance reservoir operating policies. The main objective of this PhD is to assess the economic value of SDDP-derived operating policies in large-scale water systems using various hydro-climatic information. The first task focuses on the incorporation of the multi-lag autocorrelation of the hydrologic variables in the SDDP algorithm. Afterwards, the second task is devoted to the incorporation of different exogenous hydrologic variables. The hydroelectric system of Rio Tinto (RT) located in the Saguenay-Lac-Saint-Jean River Basin is used as case study. Since, RT’s hydropower system is not able to produce the entire amount of energy demanded at the smelters to fully assure the aluminum production, a portfolio of energy contacts with Hydro-Québec is available. Eventually, we end up with a decision support system for the management of a large portfolio of physical and financial assets using various hydro-climatic information. The overall results reveal the extent of the gains in energy production that the operators can expect as more hydrologic variables are included in the state-space vector.
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Haidar, Md Atif Ibne. "Sustainable Water Allocation in Umarkhed Taluka through Optimization of Reservoir Operation in the Wardha Sub-basin, India." Ohio University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1620365781849216.

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15

Njalam'mano, John Bright Joseph. "Current Status and Management of Hand Pump Equipped Water Facilities in Blantyre Rural District, Malawi : Case Study of Kapeni and Lundu Traditional Authorities." Thesis, Linköping University, Department of Water and Environmental Studies, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8179.

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<p>Although the access to adequate safe drinking water is taken for granted in developed countries and urban settlements in some developing countries at the end of 2002 it was estimated that globally, some 1.1 billion people still rely on unsafe drinking water sources particularly in the developing regions of India and Africa. Malawi is one of the developing countries located in the arid-semiarid Sub-Saharan African region with only 62% of its people having access to safe drinking water. Boreholes and dug wells equipped with hand pumps is the technology that has assisted the country to increase the proportion of people having access to safe drinking water.</p><p>The underlying objectives of the study were to critically characterise the existing rural water facilities management systems, and to assess the status of the water facilities that were provided to rural communities by different organisations and individuals. The aim is to form an information base upon which rural water development efforts will be advanced and to expose points of intervention for sustainable rural water supply.</p><p>A survey was conducted in two traditional authorities of Kapeni and Lundu in Blantyre rural district where 94 water users were interviewed in their households. Physical inspection survey of the water facilities in the area under study was done. Focus group discussions and informal key informants’ interviews were also done.</p><p>A majority (54%) of the respondents indicated that they participated in various stages of their water supply project. The actual responsibility for the management of all water points which were visited lies with a representative group of local community known as water points committee (WPC). 97% of the water facilities that were surveyed had WPCs of which 67% received training in management, operation and maintenance (O&M) of the water facilities. There are two types of hand pumps that were found in the area, Malda and Afridev. 83% of the water facilities were still in order. The downtimes of the water facilities ranged from 1 to 360 days depending on the kind of fault.</p><p>The traditional leaders, Health Surveillance Assistants (HSAs) from government and mission clinics, water facility providers and the local communities themselves are the key players at community level. The trust that the communities have in their local leadership, the approach used in provision of the water facilities, the benefits that accrued to the local communities, and the length of time the WPCs serve the communities are the major factors that influence the communities’ participation in O&M activities. Inadequate number of qualified area technicians, theft of hand pump parts and high prices of some spare parts are some of the problems that impede effective O&M of the water facilities. To improve management, O&M of the water supply systems in the area communities have additional number of the water points, and training and refresher courses for WPCs and caretakers as some of their immediate needs. The common technical problems are hand pump related in water facilities equipped with Afridev hand pump and well drying for Malda hand pump equipped water facilities. The WPCs that are not active are those whose water facilities have been out of order for a long time. Recommendations are made regarding; planning phase, construction and operation phase, and government regulation.</p>
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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 Superior<br>This 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<br>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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Rodrigues, Carolina Bozetti. "Efeitos do manejo de florestas plantadas de Eucalyptus sobre os recursos hídricos superficiais na escala de microbacias hidrográficas." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-25072017-163038/.

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O Eucalyptus é o gênero florestal mais plantado no Brasil (5,6 milhões de hectares) e o Estado de São Paulo apresenta a segunda maior área plantada do país, com pouco mais de 970 mil hectares. O manejo intensivo das florestas plantadas de Eucalyptus, caracterizado pela alta produtividade, rápido crescimento e ciclos curtos de rotação, bem como a expansão do setor florestal, têm causado preocupações em relação aos efeitos desses plantios sobre a quantidade e a qualidade dos recursos hídricos. Diante desse contexto, esta tese foi desenvolvida com o objetivo de contribuir com o aprofundamento do conhecimento sobre os efeitos do manejo de florestas plantadas de Eucalyptus sobre os recursos hídricos. Para tanto, o segundo capítulo sintetiza os resultados de estudos já desenvolvidos no Brasil e que envolveram a mensuração de componentes do balanço hídrico em florestas plantadas de Eucalyptus e em diferentes biomas brasileiros, destacando os resultados dos estudos realizados em microbacias hidrográficas cobertas por florestas plantadas de Eucalyptus. No terceiro capítulo foram avaliados os efeitos da colheita florestal e do crescimento de florestas plantadas de Eucalyptus sobre o regime hidrológico de quatro microbacias hidrográficas e, no quarto capítulo, os efeitos sobre a qualidade da água e a exportação de nutrientes e sólidos suspensos. A revisão demonstrou que existem diferenças entre florestas plantadas de Eucalyptus e vegetação nativa, principalmente em relação aos valores anuais de rendimento hídrico (razão entre deflúvio e precipitação - Q:P), os quais tendem a diminuir, em microbacias hidrográficas, entre o primeiro e sétimo ano de idade das florestas plantadas. Os resultados demonstraram a existência de efeitos do manejo florestal como o aumento do rendimento hídrico (34%), do índice de escoamento base (4%) e do coeficiente de escoamento (21%) no primeiro ano depois da colheita (DC1) em relação ao ano anterior à colheita (AC), e a diminuição em 10%, 7% e 2%, respectivamente, no quarto ano depois da colheita (DC4) em relação ao ano DC1; o aumento da concentração de sólidos suspensos no ano DC1 em relação ao ano AC e a diminuição significativa dessas concentrações no ano DC4 em todas as microbacias estudadas; e o aumento das exportações de nutrientes e sólidos suspensos no ano DC1 acompanhando o aumento do rendimento hídrico e a diminuição das exportações no ano DC4 acompanhando a diminuição do rendimento hídrico. Em todas as escalas de análise do regime hidrológico (anual, sazonal e diária) foram observadas dinâmicas individuais nas microbacias hidrográficas diferentes daquelas observadas nos valores médios, demonstrando que outros fatores como, por exemplo, a precipitação, o tipo de solos e a declividade média, também podem influenciar o regime hidrológico além do manejo florestal. Esses efeitos demonstram que existe relação entre o manejo florestal e os recursos hídricos, mas não é possível afirmar que eles comprometem a quantidade e a qualidade da água. No entanto a conjunção entre fatores climáticos, características locais e as fases do manejo florestal pode agravar ou atenuar os efeitos sobre a quantidade e a qualidade da água, devendo esses aspectos serem observados nos planos de manejo florestal.<br>Eucalyptus is the most planted forest genus in Brazil (5.6 million hectares) and the State of São Paulo has the second largest planted area in the country, with over 970,000 hectares. The intensive management of forest plantations of Eucalyptus, characterized by high productivity, rapid growth and short rotation cycles, as well as the expansion of the forest sector, have caused concerns about the effects of these plantations on the quantity and quality of water resources. In this context, this thesis has been developed in order to contribute to the deepening of knowledge about the effects of Eucalyptus forest plantations management on water resources. Therefore, the second chapter summarizes the results of studies already developed in Brazil involving the measurement of water balance components in Eucalyptus plantations in different biomes, highlighting the results of studies in catchments covered by Eucalyptus forest plantations. In the third chapter, we evaluated the effects of Eucalyptus plantations harvesting and growth on hydrological regime of four catchments. In the fourth chapter, we evaluate effects on water quality and nutrient and suspended solids exports. The review has shown that there are differences between Eucalyptus forest plantations and native vegetation, especially in relation to annual values of discharge/precipitation ratio, which tend to decrease in catchments, between the first and seventh year on planted forests. The results demonstrated the existence of effects due to forest management such as increase in discharge/precipitation ratio (34%), base flow index (4%) and quick flow/precipitation ratio (21%), in the first year after harvest (DC1) in relation to the previous year before harvest (AC), and decreased by 10%, 7% and 2%, respectively, in the fourth year after harvest (DC4) compared to the DC1 year; concentration of suspended solids in DC1 year in relation to AC year and a significant decrease in these concentrations in DC4 year in all studied catchments; and the increase in nutrient exportation and suspended solids in DC1 year with increase in discharge/precipitation ratio and decrease in exports in the year DC4, accompanied by the decrease in discharge/precipitation ratio. In all scales of hydrological regimes (annual, seasonal and daily), individual dynamics were observed in different catchments from those observed in the mean values, demonstrating thus that other factors such as, for example, precipitation, soil type and the average slope, can also influence hydrological regime beyond forest management. These effects show that there is a relationship between forest management and water resources, but it is not possible to say that they compromise water quantity and quality. However, the conjunction of climatic factors, local conditions and stages of forest management can aggravate or mitigate the effects on water quantity and quality, and thus, such aspects should be observed in forest management plans.
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Troncoso, Raquel Ferreira. "Estudo hidrol?gico da bacia hidrogr?fica do Rio Jundia?-RN visando a implanta??o de bacia experimental e a atenua??o de cheias pela barragem Tabatinga." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15985.

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Made available in DSpace on 2014-12-17T15:03:28Z (GMT). No. of bitstreams: 1 RaquelFT_DISSERT.pdf: 4757642 bytes, checksum: d1473228d1b65e6a6e6b97e612b8485f (MD5) Previous issue date: 2012-02-28<br>The management of water resources in the river basin level, as it defines the Law n? 9433/97, requires the effective knowledge of the processes of hydrological basin, resulting from studies based on consistent series of hydrological data that reflect the characteristics of the basin. In this context, the objective of this work was to develop the modeling of catchment basin of the river Jundia? - RN and carry out the study of attenuation of a flood of the dam Tabatinga, by means of a monitoring project of hydrological data and climatology of the basin, with a view to promoting the development of research activities by applying methodologies unified and appropriate for the assessment of hydrological studies in the transition region of the semiarid and the forest zone on the coast of Rio Grande do Norte. For the study of the hydrological characteristics of the basin was conducted the automatic design of the basin of the river Jundia?, with the aid of programs of geoprocessing, was adopted a hydrological model daily, the NRCS, which is a model determined and concentrated. For the use of this model was necessary to determine some parameters that are used in this model, as the Curve Number. Having in mind that this is the first study that is being conducted in the basin with the employment of this model, it was made sensitivity analysis of the results of this model from the adoption of different values of CN, situated within a range appropriate to the conditions of use, occupation and the nature of the soil of this basin. As the objective of this study was also developing a simulation model of the operation of the Tabatinga dam and with this flood control caused in the city of Maca?ba, it was developed a mathematical model of fluid balance, developed to be used in Microsoft Excel. The simulation was conducted in two phases: the first step was promoted the water balance daily that allowed the analysis of the sensitivity of the model in relation to the volume of waiting, as well as the determination of the period of greatest discharges daily averages. From this point, it was assumed for the second stage, which was in the determination of the hydrograph of discharges effluent slots, that was determined by means of the fluid balance time, on the basis of the discharges effluents generated by a mathematical equation whose parameters were adjusted according to the hydrograph daily. Through the analyzes it was realized that the dam Tabatinga only has how to carry out the attenuation of floods through the regularization of the volume of waiting, with this there is a loss of approximately 56.5% on storage capacity of this dam, because for causing the attenuation effect of filled the shell of this dam has to remain more than 5m below the level of the sill, representing at least 50.582.927m3. The results obtained with the modeling represents a first step in the direction of improving the level of hydrological information about the behavior of the basins of the semiarid. In order to monitor quantitatively the hydrographic basin of the river Jundia? will be necessary to install a rain gauge register, next to the Tabatinga dam and a pressure transducer, for regular measurements of flow in the reservoir of the dam. The climatological data will be collected in full automatic weather station installed in Agricultural School Jundia?<br>A gest?o de recursos h?dricos em n?vel da bacia hidrogr?fica, como define a Lei n? 9433/97, exige o conhecimento efetivo dos processos hidrol?gicos da bacia, decorrentes de estudos baseados em s?ries consistentes de dados hidrol?gicos que espelhem as caracter?sticas da bacia. Neste contexto, este trabalho teve como objetivo desenvolver a modelagem hidrol?gica da bacia hidrogr?fica do rio Jundia? RN e realizar o estudo da atenua??o de cheia da barragem Tabatinga visando a implanta??o de bacia representativa e experimental, atrav?s de um projeto de monitoramento de dados hidrol?gicos e climatol?gicos da bacia, com o intuito de favorecer o desenvolvimento de atividades de pesquisa aplicando-se metodologias unificadas e apropriadas para a avalia??o de estudos hidrol?gicos na regi?o de transi??o do semi?rido e a zona da mata no litoral do Rio Grande do Norte. Para o estudo das caracter?sticas hidrol?gicas da bacia foi realizado o delineamento autom?tico da bacia hidrogr?fica do rio Jundia?, com o aux?lio de programas de geoprocessamento; adotou-se um modelo hidrol?gico di?rio, o NRCS, que ? um modelo determin?stico e concentrado. Para utiliza??o deste modelo foi necess?rio determinar alguns par?metros que s?o utilizados nesse modelo, como o Curva- N?mero. Tendo em vista que este estudo ? o primeiro que est? sendo realizado nesta bacia com o emprego deste modelo, foi feita an?lise de sensibilidade dos resultados deste modelo a partir da ado??o de diferentes valores de CN, situados dentro de uma faixa adequada ?s condi??es do uso, ocupa??o e natureza do solo desta bacia. Como o objetivo deste estudo foi tamb?m desenvolver um modelo de simula??o de opera??o da barragem Tabatinga e com isto controlar as inunda??es ocasionadas na cidade de Maca?ba, foi elaborado um modelo matem?tico de balan?o h?drico, desenvolvido para ser aplicado em planilha Microsoft Excel. A simula??o foi realizada em duas etapas: na primeira etapa promoveu-se o balan?o h?drico di?rio que permitiu analisar a sensibilidade do modelo em rela??o ao volume de espera, assim como a determina??o do per?odo de maiores vaz?es m?dias di?rias. A partir disso, partiu-se para a segunda etapa, que constituiu na determina??o do hidrograma das vaz?es efluentes hor?rias, que foi determinado atrav?s do balan?o h?drico hor?rio, tendo como base as vaz?es afluentes geradas por uma equa??o matem?tica cujos par?metros foram ajustados de acordo com o hidrograma di?rio. Atrav?s das an?lises percebeu-se que a barragem Tabatinga s? tem como realizar a atenua??o de cheias atrav?s da regulariza??o do volume de espera, com isso h? uma perda de aproximadamente 56,5% na capacidade de armazenamento desta barragem, pois para provocar o efeito de atenua??o de cheia o reservat?rio dessa barragem tem que permanecer mais de 5m abaixo do n?vel da soleira, representando no m?nimo 50.582.927 m3. Os resultados obtidos com a modelagem representam um primeiro passo na dire??o de melhorar o n?vel de informa??o hidrol?gica sobre o comportamento das bacias do semi?rido. Nesse intuito, para monitorar quantitativamente a bacia hidrogr?fica do rio Jundia? ser? necess?rio instalar um pluvi?grafo, pr?ximo a barragem Tabatinga e um lin?grafo de press?o, para medi??es regulares de vaz?o no reservat?rio da barragem. Os dados climatol?gicos ser?o coletados na esta??o meteorol?gica autom?tica completa instalada na Escola Agr?cola Jundia?
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Philipp, Andy. "Novel Analytical Hydrodynamic Modeling for Evaluating and Optimizing Alluvial Recharge." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-124891.

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This thesis presents a novel analytical solution strategy for the zero-inertia (ZI) equations of free surface flow. These equations are utilized herein for routing flood flow in open channels and for simulating excess rainfall runoff on overland planes. The novel solution approach is shown to be both accurate and robust, especially under the complicated and intricate conditions of infiltrating flow on initially dry river beds or soils, e.g., as present in arid and semiarid areas. This is underlain by comparing modeling results of the novel analytical procedure with those of validated numerical solutions. Furthermore, it is shown that the analytical ZI model can deliver a process-oriented portrayal of runoff concentration in the flood-generating parts of the catchment. Subsequently, the novel analytical ZI model is applied for a real-world water management problem in the Sultanate of Oman, Arabian Peninsula. Within an integrated flash flood routing model—which is also presented in this thesis—the novel analytical routing approach helps in accurately matching the dynamics of advancing and infiltrating ephemeral river flow, established as a consequence of release from a groundwater recharge dam. The integrated modeling system houses the aforementioned analytical downstream model and tailor-made, state-of-the-art modeling components to portray the upstream flow processes, dam operation (including evaporation), and spillway release flow. The proposed modeling system can aid in rendering a realistic image of transient transmission losses and dependent flow dynamics. This is of extremely high importance for water resources assessment, as well as for optimizing recharge dam operation strategies in order to maximize downstream transmission losses and, thus, groundwater recharge<br>Diese Dissertation präsentiert einen neuartigen analytischen Lösungsansatz für das beschleunigungsfreie Wellenmodell (bzw. „Zero-Inertia-Modell“, „ZI-Modell“, oder „diffusives Wellenmodell“). Im Rahmen der Arbeit wird das hergeleitete hydrodynamische Modell sowohl zur Simulation von Freispiegelabflüssen in nichtprismatischen und durchlässigen Gerinnen, als auch für die Beschreibung von auf der Landoberfläche abfließendem Infiltrationsüberschuss eingesetzt. Es wird gezeigt, dass der neuartige analytische Ansatz — im Hinblick auf Massenerhaltung und die exakte Abbildung der Abflussdynamik — akkurate Ergebnisse liefert und gleichzeitig unter komplexen und verwickelten Prozessbedingungen anwendbar ist. So belegt eine vergleichende Analyse mit validierten numerischen Lösungsansätzen die Robustheit des analytischen ZI-Modells. Insbesondere die im Sinne der numerischen Mathematik stabile und genaue Modellierung der gekoppelten Abfluss- und Infiltrationsvorgänge in anfänglich trockenen Gerinnen ist dabei ein Novum. Weiterhin wird die Eignung und Anwendbarkeit des neuartigen Modellansatzes zur Beschreibung der Abflusskonzentrationsprozesse gezeigt. Der neuartige Lösungsansatz wird im Folgenden für ein reales Wassermanagementproblem im Sultanat Oman, Arabische Halbinsel eingesetzt. Als Bestandteil eines integrierten Modellsystems, welches ebenfalls im Rahmen der Dissertation vorgestellt wird, dient das analytische ZI-Modell zur Simulation von infiltrierendem Wadiabfluss, welcher unterstrom von Grundwasseranreicherungsdämmen starke Verluste von Masse und Impuls erfährt. Zusammen mit maßgeschneiderten und dem Stand der Technik entsprechenden Komponenten für die Betriebssimulation des Anreicherungsdammes (inklusive Verdunstung von der freien Seefläche) sowie für die Abbildung der oberstromigen hydrodynamischen Prozesse (ebenfalls inklusive Infiltration) wird der neuartige analytische Ansatz in einem Modellsystem zusammengefasst. Das Modellsystem ist in der Lage ein realistisches Bild der raumzeitlichen Dynamik des Abflusses sowie der Grundwasserneubildung aus infiltrierendem Wadiabfluss zu liefern. Damit stellt das Modellsystem ein wertvolles Werkzeug sowohl zur Wasserdargebotsermittlung, als auch für die Optimierung des Betriebes von Grundwasseranreicherungsdämmen dar
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Slota, Phillip Michael Anton. "Evaluation of operational lake evaporation methods in a Canadian Shield landscape." 2013. http://hdl.handle.net/1993/22103.

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This thesis presents the findings of a study examining the hydrological processes controlling lake evaporation in a Canadian Shield landscape. The purpose of this study is to provide a recommendation on a suitable operational lake evaporation method for implementation in a partially-physically-based meso-scale hydrological model to improve simulation of the climate-hydrological feedback loop. Detailed hydroclimatic observations were recorded for two lakes located in northwestern Ontario, Canada to estimate actual lake evaporation using a Bowen ratio energy balance approach. Multiple operational lake evaporation methods were evaluated for their ability to reproduce the reference lake evaporation rates. Each method was tested for its sensitivity to regionalized and estimated forcing data. The results of this study found a modified version of the Priestley-Taylor combination method most accurately reproduced measured lake evaporation. This method incorporates a novel lumped lake heat storage model developed to estimate heat storage fluxes using re-gional climatic forcing.
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Bezuidenhout, Carel Nicolaas. "Development and evaluation of model-based operational yield forecasts in the South African sugar industry." Thesis, 2005. http://hdl.handle.net/10413/5336.

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South Africa is the largest producer of sugar in Africa and one of the ten largest sugarcane producers in the world. Sugarcane in South Africa is grown under a wide range of agro-climatic conditions. Climate has been identified as the single most important factor influencing sugarcane production in South Africa. Traditionally, sugarcane mill committees have issued forecasts of anticipated production for a region. However, owing to several limitations of such committee forecasts, more advanced technologies have had to be considered. The aim of this study has been to develop, evaluate and implement a pertinent and technologically advanced operational sugarcane yield forecasting system for South Africa. Specific objectives have included literature and technology reviews, surveys of stakeholder requirements, the development and evaluation of a forecasting system and the assessment of information transfer and user adoption. A crop yield model-based system has been developed to simulate representative crops for derived Homogeneous Climate Zones (HCZ). The system has integrated climate data and crop management, soil, irrigation and seasonal rainfall outlook information. Simulations of yields were aggregated from HCZs to mill supply area and industry scales and were compared with actual production. The value of climate information (including climate station networks) and seasonal rainfall outlook information were quantified independently. It was concluded that the system was capable of forecasting yields with acceptable accuracy over a wide range of agro-climatic conditions in South Africa. At an industry scale, the system captured up to 58% of the climatically driven variability in mean annual sugarcane yields. Forecast accuracies differed widely between different mill supply areas, and several factors were identified that may explain some inconsistencies. Seasonal rainfall outlook information generally enhanced forecasts of sugarcane production. Rainfall outlooks issued during the summer months seemed more valuable than those issued in early spring. Operationally, model-based forecasts can be expected to be valuable prior to the commencement of the milling season in April. Current limitations of forecasts include system calibration, the expression of production relative to that of the previous season and the omission of incorporating near real-time production and climate information. Several refinements to the forecast system are proposed and a strong collaborative approach between modellers, climatologists, mill committees and other decision makers is encouraged.<br>Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
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"Real time control in water resource operations." Tulane University, 2005.

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The objective of this research is to determine what is a time optimal control for diafiltration membrane separation processes. Diafiltration membrane separation is a dewatering process of a slurry from an initial bulk phase concentration (C0) to a final bulk phase concentration (C b,f). When rates of the material entering the system match rates leaving as a permeate, it is termed permeate matching diafiltration. Managing the controlled variables of the system in a time optimal manner maximizes the solid production capacity. Time optimal controllers have been used in many practical applications, but it has not been applied to water resources management The case study for this dissertation is a particular ultrafiltration process (UFP) to be used at the Hanford Department of Energy (DOE) facility, which is a pinch-point of a proposed Waste Treatment Plant (WTP) for the treatment of low activity waste (LAW) and high level waste (HLW). Improving the performance of the UFP will directly improve the performance of the WTP. It is asserted that the feed into the UFP and transmembrane pressure differential (TMP) should be allowed to vary with time to minimize the time needed to go from C 0 to Cb,f. This form of diafiltration is termed time optimal diafiltration It will be shown that permeate matching diafiltration and time optimal diafiltration are equivalent in terms of dewatering times, but that permeate matching diafiltration is open loop. Time optimal diafiltration will be shown to exhibit feedback through the use of sliding mode control. The advantage of this closed loop approach will be demonstrated. Furthermore, an empirical relationship is derived for the optimal time of dewatering associated with permeate matching diafiltration that can be used for sizing ultrafiltration processes<br>acase@tulane.edu
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Fair, Kerry. "Developing a real time hydraulic model and a decision support tool for the operation of the Orange River." Thesis, 2002. http://hdl.handle.net/10413/4674.

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This thesis describes the development of a decision support tool to be used in the operation of Vanderkloof Dam on the Orange River so that the supply of water to the lower Orange River can be optimised. The decision support tool is based on a hydrodynamic model that was customised to incorporate real time data recorded at several points on the river. By incorporating these data into the model the simulated flows are corrected to the actual flow conditions recorded on the river, thereby generating a best estimate of flow conditions at any given time. This information is then used as the initial conditions for forecast simulations to assess whether the discharge volumes and schedules from the dam satisfy the water demands of downstream users, some of which are 1400km or up to 8 weeks away. The various components of the decision support system, their functionality and their interaction are described. The details regarding the development of these components include: • The hydraulic model of the Orange River downstream of Vanderkloof Dam. The population and calibration of the model are described. • The modification of the code of the hydrodynamic engine so that real time recorded stage and flow data can be incorporated into the model • The development of a graphical user interface to facilitate the exchange of data between the real time network of flow gauging stations on the Orange River and the hydraulic model • The investigation into the effect of including the real time data on the simulated flows • Testing the effectiveness of the decision support system.<br>Thesis (M.Sc.)-University of Natal, Durban, 2002.
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Drake, Jennifer Anne Pauline. "Performance and Operation of Partial Infiltration Permeable Pavement Systems in the Ontario Climate." Thesis, 2009. http://hdl.handle.net/10214/7277.

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Partial-infiltration permeable pavement (PP) systems provide environmental benefits by increasing infiltration, attenuating storm flows and improving stormwater quality. This thesis focuses on the performance and operation of partial-infiltration PP systems over low permeability soil in Ontario. Three PP, AquaPave®, Eco-Optiloc® and Hydromedia® Pervious Concrete were monitored over two years and their performance was evaluated relative to an impermeable Asphalt control. Field data was collected from the Kortright PP pilot parking lot in Vaughan, Ontario. Through the use of restrictor valves on underdrains the PP systems were shown to provide substantial hydrologic benefits by eliminating stormwater outflow for rain events less than 7mm, reducing peak flows by 91% and reducing total stormwater volume by 43%. Stormwater quality was analyzed for winter and non-winter seasons. The PP were shown to greatly reduce the concentration and total loading of suspended solids, nutrients, hydrocarbons and most heavy metals. Some water quality data, such as pH, K, or Sr levels, indicate that the quality of PP effluent will change as the system ages. Study of PP sample boxes at the University of Guelph highlighted the role that construction materials have on effluent quality and showed that pollutants introduced by the pavement and aggregate are almost entirely in a dissolved form and decline very rapidly after a season of exposure to rainfall. Benefits to water quality were sustained during winter months. The partial-infiltration PP systems were shown to provide buffering of Na and Cl concentrations. Small and large-scale maintenance practices for PP systems were investigated. Small-sized equipment testing found that vacuum cleaning and pressure-washing have good potential to improve infiltration capacity. Testing of full-sized streetsweeping trucks demonstrated that permeability can be partially restored on PICP by suction-based sweeping. Vacuum-sweeping was beneficial on a PC pavement which had experienced large permeability losses. Results of this study indicate that partial-infiltration PP systems can be effective measures for maintaining or restoring infiltration functions on parking lots and other low volume traffic areas, even in areas with low permeability soils.
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Turton, Anthony Richard. "The hydropolitics of Southern Africa: the case of the Zambezi river basin as an area of potential co-operation based on Allan's concept of virtual water." Diss., 1998. http://hdl.handle.net/10500/16231.

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Southern Africa generally has an arid climate and many hydrologists are predicting an increase in water scarcity over time. This research seeks to understand the implications of this in socio-political terms. The study is cross-disciplinary, examining how policy interventions can be used to solve the problem caused by the interaction between hydrology and demography. The conclusion is that water scarcity is not the actual problem, but is perceived as the problem by policy-makers. Instead, water scarcity is the manifestation of the problem, with root causes being a combination of climate change, population growth and misallocation of water within the economy due to a desire for national self-sufficiency in agriculture. The solution lies in the trade of products with a high water content, also known as 'virtual water'. Research on this specific issue is called for by the White Paper on Water Policy for South Africa.<br>Political Sciences<br>M.A. (International Politics)
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Reddy, Manne Janga. "Swarm Intelligence And Evolutionary Computation For Single And Multiobjective Optimization In Water Resource Systems." Thesis, 2006. http://hdl.handle.net/2005/370.

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Most of the real world problems in water resources involve nonlinear formulations in their solution construction. Obtaining optimal solutions for large scale nonlinear optimization problems is always a challenging task. The conventional methods, such as linear programming (LP), dynamic programming (DP) and nonlinear programming (NLP) may often face problems in solving them. Recently, there has been an increasing interest in biologically motivated adaptive systems for solving real world optimization problems. The multi-member, stochastic approach followed in Evolutionary Algorithms (EA) makes them less susceptible to getting trapped at local optimal solutions, and they can search easier for global optimal solutions. In this thesis, efficient optimization techniques based on swarm intelligence and evolutionary computation principles have been proposed for single and multi-objective optimization in water resource systems. To overcome the inherent limitations of conventional optimization techniques, meta-heuristic techniques like ant colony optimization (ACO), particle swarm optimization (PSO) and differential evolution (DE) approaches are developed for single and multi-objective optimization. These methods are then applied to few case studies in planning and operation of reservoir systems in India. First a methodology based on ant colony optimization (ACO) principles is investigated for reservoir operation. The utility of the ACO technique for obtaining optimal solutions is explored for large scale nonlinear optimization problems, by solving a reservoir operation problem for monthly operation over a long-time horizon of 36 years. It is found that this methodology relaxes the over-year storage constraints and provides efficient operating policy that can be implemented over a long period of time. By using ACO technique for reservoir operation problems, some of the limitations of traditional nonlinear optimization methods are surmounted and thus the performance of the reservoir system is improved. To achieve faster optimization in water resource systems, a novel technique based on swarm intelligence, namely particle swarm optimization (PSO) has been proposed. In general, PSO has distinctly faster convergence towards global optimal solutions for numerical optimization. However, it is found that the technique has the problem of getting trapped to local optima while solving real world complex problems. To overcome such drawbacks, the standard particle swarm optimization technique has been further improved by incorporating a novel elitist-mutation (EM) mechanism into the algorithm. This strategy provides proper exploration and exploitation throughout the iterations. The improvement is demonstrated by applying it to a multi-purpose single reservoir problem and also to a multi reservoir system. The results showed robust performance of the EM-PSO approach in yielding global optimal solutions. Most of the practical problems in water resources are not only nonlinear in their formulations but are also multi-objective in nature. For multi-objective optimization, generating feasible efficient Pareto-optimal solutions is always a complicated task. In the past, many attempts with various conventional approaches were made to solve water resources problems and some of them are reported as successful. However, in using the conventional linear programming (LP) and nonlinear programming (NLP) methods, they usually involve essential approximations, especially while dealing withdiscontinuous, non-differentiable, non-convex and multi-objective functions. Most of these methods consider multiple objective functions using weighted approach or constrained approach without considering all the objectives simultaneously. Also, the conventional approaches use a point-by-point search approach, in which the outcome of these methods is a single optimal solution. So they may require a large number of simulation runs to arrive at a good Pareto optimal front. One of the major goals in multi-objective optimization is to find a set of well distributed optimal solutions along the true Pareto optimal front. The classical optimization methods often fail to attain a good and true Pareto optimal front due to accretion of the above problems. To overcome such drawbacks of the classical methods, there has recently been an increasing interest in evolutionary computation methods for solving real world multi-objective problems. In this thesis, some novel approaches for multi-objective optimization are developed based on swarm intelligence and evolutionary computation principles. By incorporating Pareto optimality principles into particle swarm optimization algorithm, a novel approach for multi-objective optimization has been developed. To obtain efficient Pareto-frontiers, along with proper selection scheme and diversity preserving mechanisms, an efficient elitist mutation strategy is proposed. The developed elitist-mutated multi-objective particle swarm optimization (EM-MOPSO) technique is tested for various numerical test problems and engineering design problems. It is found that the EM-MOPSO algorithm resulting in improved performance over a state-of-the-art multi-objective evolutionary algorithm (MOEA). The utility of EM-MOPSO technique for water resources optimization is demonstrated through application to a case study, to obtain optimal trade-off solutions to a reservoir operation problem. Through multi-objective analysis for reservoir operation policies, it is found that the technique can offer wide range of efficient alternatives along with flexibility to the decision maker. In general, most of the water resources optimization problems involve interdependence relations among the various decision variables. By using differential evolution (DE) scheme, which has a proven ability of effective handling of this kind of interdependence relationships, an efficient multi-objective solver, namely multi-objective differential evolution (MODE) is proposed. The single objective differential evolution algorithm is extended to multi-objective optimization by integrating various operators like, Pareto-optimality, non-dominated sorting, an efficient selection strategy, crowding distance operator for maintaining diversity, an external elite archive for storing non- dominated solutions and an effective constraint handling scheme. First, different variations of DE approaches for multi-objective optimization are evaluated through several benchmark test problems for numerical optimization. The developed MODE algorithm showed improved performance over a standard MOEA, namely non-dominated sorting genetic algorithm–II (NSGA-II). Then MODE is applied to a case study of Hirakud reservoir operation problem to derive operational tradeoffs in the reservoir system optimization. It is found that MODE is achieving robust performance in evaluation for the water resources problem, and that the interdependence relationships among the decision variables can be effectively modeled using differential evolution operators. For optimal utilization of scarce water resources, an integrated operational model is developed for reservoir operation for irrigation of multiple crops. The model integrates the dynamics associated with the water released from a reservoir to the actual water utilized by the crops at farm level. It also takes into account the non-linear relationship of root growth, soil heterogeneity, soil moisture dynamics for multiple crops and yield response to water deficit at various growth stages of the crops. Two types of objective functions are evaluated for the model by applying to a case study of Malaprabha reservoir project. It is found that both the cropping area and economic benefits from the crops need to be accounted for in the objective function. In this connection, a multi-objective frame work is developed and solved using the MODE algorithm to derive simultaneous policies for irrigation cropping pattern and reservoir operation. It is found that the proposed frame work can provide effective and flexible policies for decision maker aiming at maximization of overall benefits from the irrigation system. For efficient management of water resources projects, there is always a great necessity to accurately forecast the hydrologic variables. To handle uncertain behavior of hydrologic variables, soft computing based artificial neural networks (ANNs) and fuzzy inference system (FIS) models are proposed for reservoir inflow forecasting. The forecast models are developed using large scale climate inputs like indices of El-Nino Southern Oscialltion (ENSO), past information on rainfall in the catchment area and inflows into the reservoir. In this purpose, back propagation neural network (BPNN), hybrid particle swarm optimization trained neural network (PSONN) and adaptive network fuzzy inference system (ANFIS) models have been developed. The developed models are applied for forecasting inflows into the Malaprabha reservoir. The performances of these models are evaluated using standard performance measures and it is found that the hybrid PSONN model is performing better than BPNN and ANFIS models. Finally by adopting PSONN model for inflow forecasting and EMPSO technique for solving the reservoir operation model, the practical utility of the different models developed in the thesis are demonstrated through application to a real time reservoir operation problem. The developed methodologies can certainly help in better planning and operation of the scarce water resources.
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