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Methodology for the optimal management design of water resources system under hydrologic uncertaintyHaro Monteagudo, David 12 January 2015 (has links)
Un sistema de gestión de sequías apropiado requiere de la anticipación de los posibles
efectos que un episodio de este tipo tenga sobre el sistema de recursos hídricos. Esta tarea sin
embargo resulta más complicada de lo que parece. En primer lugar, debido al alto grado de
incertidumbre existente en la predicción de variables hidrológicas futuras. Y en segundo,
debido al riesgo de sobrerreacción en la activación de medidas de mitigación generando falsa
sensación de escasez, o sequía artificial. A este respecto, los planes especiales de sequía
proveen de herramientas para la gestión eficiente de situaciones con escasez de recursos y la
preparación de cara a futuros eventos. De todos modos, las diferentes estrategias de
operación seguidas en cada sistema de recursos hídricos hacen que las herramientas que en
algunos casos resultaron altamente útiles no lo sean tanto cuando se aplican en sistemas
distintos.
Debido a la falta de tiempo y/o al exceso de confianza en los trabajos realizados por
terceros, con excelentes resultados en sus respectivos casos, a veces se cae en el error de
implementar metodologías no del todo apropiadas en sistemas con requisitos completamente
distintos. El desarrollo y utilización de metodologías generalizadas aplicables a diferentes
sistemas y capaces de proporcionar resultados adaptados a cada caso es, por tanto, muy
deseable. Este es el caso de las herramientas de modelación de sistemas de recursos hídricos
generalizadas. Estas permiten homogeneizar los procesos mientras siguen siendo los
suficientemente adaptables para proporcionar resultados apropiados para cada caso de
estudio.
Esta tesis presenta una serie de herramientas destinadas a avanzar en el análisis y
comprensión de los sistemas de recursos hídricos, haciendo énfasis en la prevención de
sequías y la gestión de riesgos. Las herramientas desarrolladas incluyen: un modelo de
optimización generalizado para esquemas de recursos hídricos, con capacidad para la
representación detallada de cualquier sistema de recursos hídricos, y una metodología de
análisis de riesgo basada en la optimización de Monte Carlo con múltiples series sintéticas. Con
estas herramientas es posible incluir tanto la componente superficial como la subterránea del
sistema estudiado dentro del proceso de optimización. La optimización está basada en la
resolución iterativa de redes de flujo. Se probó la consistencia y eficiencia de diferentes
algoritmos de resolución para encontrar un balance entre la velocidad de cálculo, el número
de iteraciones, y la consistencia de los resultados, aportando recomendaciones para el uso de
cada algoritmo dadas las diferencias entre los mismos.
Las herramientas desarrolladas se aplican en dos casos de estudio reales en la
evaluación y posibilidad de complementación de los sistemas de monitorización y alerta
temprana de sequías existentes en los mismos. En el primer caso, se propone un enfoque
alternativo para la monitorización de la sequía en el sistema de operación anual del río Órbigo
(España), complementándolo con la utilización de la metodología de análisis de riesgo. En el
segundo caso, las herramientas se emplean en un sistema con una estrategia de operación
completamente distinta. Se estudia como el análisis de riesgo de la gestión óptima puede
ayudar a la activación anticipada de los escenarios de sequía en los sistemas de los ríos Júcar y
Turia, cuya operación es hiperanual. En esta ocasión, el sistema de indicadores existente goza
de una gran confianza por parte de los usuarios. La metodología de análisis de riesgo es, sin
embargo, capaz de anticipar los eventos de sequía con mayor alarma, aspecto que es deseable
si se quiere evitar que los episodios en desarrollo vayan a más. En ambos casos se muestra
como la evaluación anticipada de las posibles situaciones futuras del sistema permiten una
definición confiable de los escenarios de sequía con suficiente antelación para la activación
efectiva de medidas de prevención y/o mitigación en caso de ser necesarias.
La utilización de indicadores provenientes de modelos frente a indicadores basados en
datos observados es complementaria y ambos deberían utilizarse de forma conjunta para
mejorar la gestión preventiva de los sistemas de recursos hídricos. El empleo de modelos de
optimización en situaciones de incertidumbre hidrológica es muy apropiado gracias a la no
necesidad de definir reglas de gestión para obtener los mejores resultados del sistema, y
teniendo en cuenta que las reglas de operación habituales pueden no ser completamente
adecuadas en estas ocasiones. / Haro Monteagudo, D. (2014). Methodology for the optimal management design of water resources system under hydrologic uncertainty [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/45996 / TESIS
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Improving hydrological post-processing for assessing the conditional predictive uncertainty of monthly streamflowsRomero Cuellar, Jonathan 07 January 2020 (has links)
[ES] La cuantificación de la incertidumbre predictiva es de vital importancia para producir predicciones hidrológicas confiables que soporten y apoyen la toma de decisiones en el marco de la gestión de los recursos hídricos. Los post-procesadores hidrológicos son herramientas adecuadas para estimar la incertidumbre predictiva de las predicciones hidrológicas (salidas del modelo hidrológico). El objetivo general de esta tesis es mejorar los métodos de post-procesamiento hidrológico para estimar la incertidumbre predictiva de caudales mensuales. Esta tesis pretende resolver dos problemas del post-procesamiento hidrológico: i) la heterocedasticidad y ii) la función de verosimilitud intratable. Los objetivos específicos de esta tesis son tres. Primero y relacionado con la heterocedasticidad, se propone y evalúa un nuevo método de post-procesamiento llamado GMM post-processor que consiste en la combinación del esquema de modelado de probabilidad Bayesiana conjunta y la mezcla de Gaussianas múltiples. Además, se comparó el desempeño del post-procesador propuesto con otros métodos tradicionales y bien aceptados en caudales mensuales a través de las doce cuencas hidrográficas del proyecto MOPEX. A partir de este objetivo (capitulo 2), encontramos que GMM post-processor es el mejor para estimar la incertidumbre predictiva de caudales mensuales, especialmente en cuencas de clima seco.
Segundo, se propone un método para cuantificar la incertidumbre predictiva en el contexto de post-procesamiento hidrológico cuando sea difícil calcular la función de verosimilitud (función de verosimilitud intratable). Algunas veces en modelamiento hidrológico es difícil calcular la función de verosimilitud, por ejemplo, cuando se trabaja con modelos complejos o en escenarios de escasa información como en cuencas no aforadas. Por lo tanto, se propone el ABC post-processor que intercambia la estimación de la función de verosimilitud por el uso de resúmenes estadísticos y datos simulados. De este objetivo específico (capitulo 3), se demuestra que la distribución predictiva estimada por un método exacto (MCMC post-processor) o por un método aproximado (ABC post-processor) es similar. Este resultado es importante porque trabajar con escasa información es una característica común en los estudios hidrológicos.
Finalmente, se aplica el ABC post-processor para estimar la incertidumbre de los estadísticos de los caudales obtenidos desde las proyecciones de cambio climático, como un caso particular de un problema de función de verosimilitud intratable. De este objetivo específico (capitulo 4), encontramos que el ABC post-processor ofrece proyecciones de cambio climático más confiables que los 14 modelos climáticos (sin post-procesamiento). De igual forma, ABC post-processor produce bandas de incertidumbre más realista para los estadísticos de los caudales que el método clásico de múltiples conjuntos (ensamble). / [CA] La quantificació de la incertesa predictiva és de vital importància per a produir prediccions hidrològiques confiables que suporten i recolzen la presa de decisions en el marc de la gestió dels recursos hídrics. Els post-processadors hidrològics són eines adequades per a estimar la incertesa predictiva de les prediccions hidrològiques (eixides del model hidrològic). L'objectiu general d'aquesta tesi és millorar els mètodes de post-processament hidrològic per a estimar la incertesa predictiva de cabals mensuals. Els objectius específics d'aquesta tesi són tres. Primer, es proposa i avalua un nou mètode de post-processament anomenat GMM post-processor que consisteix en la combinació de l'esquema de modelatge de probabilitat Bayesiana conjunta i la barreja de Gaussianes múltiples. A més, es compara l'acompliment del post-processador proposat amb altres mètodes tradicionals i ben acceptats en cabals mensuals a través de les dotze conques hidrogràfiques del projecte MOPEX. A partir d'aquest objectiu (capítol 2), trobem que GMM post-processor és el millor per a estimar la incertesa predictiva de cabals mensuals, especialment en conques de clima sec.
En segon lloc, es proposa un mètode per a quantificar la incertesa predictiva en el context de post-processament hidrològic quan siga difícil calcular la funció de versemblança (funció de versemblança intractable). Algunes vegades en modelació hidrològica és difícil calcular la funció de versemblança, per exemple, quan es treballa amb models complexos o amb escenaris d'escassa informació com a conques no aforades. Per tant, es proposa l'ABC post-processor que intercanvia l'estimació de la funció de versemblança per l'ús de resums estadístics i dades simulades. D'aquest objectiu específic (capítol 3), es demostra que la distribució predictiva estimada per un mètode exacte (MCMC post-processor) o per un mètode aproximat (ABC post-processor) és similar. Aquest resultat és important perquè treballar amb escassa informació és una característica comuna als estudis hidrològics.
Finalment, s'aplica l'ABC post-processor per a estimar la incertesa dels estadístics dels cabals obtinguts des de les projeccions de canvi climàtic. D'aquest objectiu específic (capítol 4), trobem que l'ABC post-processor ofereix projeccions de canvi climàtic més confiables que els 14 models climàtics (sense post-processament). D'igual forma, ABC post-processor produeix bandes d'incertesa més realistes per als estadístics dels cabals que el mètode clàssic d'assemble. / [EN] The predictive uncertainty quantification in monthly streamflows is crucial to make reliable hydrological predictions that help and support decision-making in water resources management. Hydrological post-processing methods are suitable tools to estimate the predictive uncertainty of deterministic streamflow predictions (hydrological model outputs). In general, this thesis focuses on improving hydrological post-processing methods for assessing the conditional predictive uncertainty of monthly streamflows. This thesis deal with two issues of the hydrological post-processing scheme i) the heteroscedasticity problem and ii) the intractable likelihood problem. Mainly, this thesis includes three specific aims. First and relate to the heteroscedasticity problem, we develop and evaluate a new post-processing approach, called GMM post-processor, which is based on the Bayesian joint probability modelling approach and the Gaussian mixture models. Besides, we compare the performance of the proposed post-processor with the well-known exiting post-processors for monthly streamflows across 12 MOPEX catchments. From this aim (chapter 2), we find that the GMM post-processor is the best suited for estimating the conditional predictive uncertainty of monthly streamflows, especially for dry catchments.
Secondly, we introduce a method to quantify the conditional predictive uncertainty in hydrological post-processing contexts when it is cumbersome to calculate the likelihood (intractable likelihood). Sometimes, it can be challenging to estimate the likelihood itself in hydrological modelling, especially working with complex models or with ungauged catchments. Therefore, we propose the ABC post-processor that exchanges the requirement of calculating the likelihood function by the use of some sufficient summary statistics and synthetic datasets. With this aim in mind (chapter 3), we prove that the conditional predictive distribution is similarly produced by the exact predictive (MCMC post-processor) or the approximate predictive (ABC post-processor), qualitatively speaking. This finding is significant because dealing with scarce information is a common condition in hydrological studies.
Finally, we apply the ABC post-processing method to estimate the uncertainty of streamflow statistics obtained from climate change projections, such as a particular case of intractable likelihood problem. From this specific objective (chapter 4), we find that the ABC post-processor approach: 1) offers more reliable projections than 14 climate models (without post-processing); 2) concerning the best climate models during the baseline period, produces more realistic uncertainty bands than the classical multi-model ensemble approach. / I would like to thank the Gobernación del Huila Scholarship Program No. 677
(Colombia) for providing the financial support for my PhD research. / Romero Cuellar, J. (2019). Improving hydrological post-processing for assessing the conditional predictive uncertainty of monthly streamflows [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/133999 / TESIS
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Aplicação de algoritmos evolucionários à gestão integrada de sistemas de recursos hídricos. / The use of multi-objective evolucionary algorithms in water resource management.Schardong, André 20 June 2011 (has links)
Esta tese estudou a aplicação de algoritmos evolucionários na análise multiobjetivo para gestão integrada de sistemas de recursos hídricos, bem como a sua integração à sistemas de suporte a decisão como o SSD AcquaNet e ModSim DSS. Dois algoritmos evolucionários multi-objetivo são desenvolvidos: MoDE-NS e MoPSO-NS e comparados ao NSGA-II. Os algoritmos foram desenvolvidos em forma de Sistema de Otimização que possibilita a análise de problemas multi-objetivo de forma generalizada com foco em sistemas de recursos hídricos. A possibilidade de integração com o SSD AcquaNet e o ModSim DSS via importação de rede de fluxo e a otimização conjunta, são apresentadas e exploradas. Uma ferramenta de visualização gráfica do conjunto de soluções não dominadas é incluída no Sistema de Otimização. Os algoritmos desenvolvidos foram aplicados a problemas de teste padrão para validação através da comparação de seus resultados ao NSGA-II. As possibilidades de aplicação do sistema de otimização e dos algoritmos evolucionários multi-objetivo foram exploradas inicialmente através de análise multi-objetivo do modelo chuva-vazão Smap com dois e cinco objetivos. Em seguida, a análise foi estendida a um sistema de recursos hídricos complexo, o Sistema Cantareira, responsável pelo abastecimento de aproximadamente metade da RMSP, que corresponde à aproximadamente 33 m³/s. A análise foi realizada comparando dois pares de funções objetivos envolvendo custos de energia elétrica, minimização de déficit no atendimento às demandas e minimização do desvio da qualidade da água em relação à Classe de enquadramento no rio Atibaia, a jusante do reservatório Atibainha e Cachoeira. Os resultados apontam que os algoritmos evolucionários multi-objetivo são aptos para aplicação na análise integrada de sistemas de recursos hídricos e representam uma boa alternativa aos métodos denominados clássicos, pelas suas características peculiares discutidas no trabalho. Algumas recomendações quanto ao uso dos algoritmos abordados para análise de problemas multi-objetivo foram apresentados. / This Thesis presents an application of evolutionary algorithms in multi-objective analysis for integrated management of water resources systems and their integration into decision support systems as AcquaNet and ModSim DSS. Two multi-objective evolutionary algorithms are developed: MoDE-NS-NS and MoPSO-NS and compared to NSGA-II. The algorithms are developed in the form of Optimization System which enables generalized multi-objective analysis with a focus on water resources systems. The possibilities for integration with AcquaNet and ModSim DSS, by importing network flow directly from them or by integrated optimization/simulation are also presented. A graphical visualization tool for the set of non-dominated solutions is also included in Optimization System. The algorithms are applied to common test problems set for validation by comparing its results to the NSGA-II. The possibilities of application of the developed Optimization System and multi-objective evolutionary algorithms are initially exploited by multi-objective analysis of a hydrological rainfall-runoff model Smap, with two and five objectives. Then, the analysis is extended to a complex water resources system, the Cantareira System, responsible for supplying nearly half of the Sao Paulo metro area, which corresponds to approximately 33 m³/s. The analysis is done by comparing two pairs of objective functions: minimization of demand shortage versus minimization of pumping cost and minimization of demand shortage versus minimization of the deviation from water quality standards. The results show that the multi-objective evolutionary algorithms are suitable for application to integrated analysis of water resources systems and represent a good alternative to the so called classical methods, for its peculiar characteristics discussed on this thesis. The MoDE-NS and MoPSO-NS developed, outperformed NSGA-II results, by obtaining a better coverage of the Pareto fronts especially on the water resources system case study.
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Modelo para simulação de nitrogênio e fósforo em sistemas de recursos hídricos, aplicação em região do alto curso do Rio Piranhas-PB.NEPOMUCENO, Thiago Cabral. 13 April 2018 (has links)
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Previous issue date: 2018-02-27 / Capes / O lançamento de efluentes domésticos em ambientes aquáticos sem o devido tratamento vem comprometendo a qualidade da água de reservatórios e rios. Esta torna-se ainda mais relevante quando, em torno desses corpos hídricos superficiais, existe uma intensa prática agrícola, com aplicação de fertilizantes a base de nitrogênio e fósforo, onde a ocorrência de eventos chuvosos pode gerar escoamento superficial e encaminhar o excesso desses nutrientes presentes no solo para os rios e reservatórios próximos. Portanto, o presente trabalho propôs o desenvolvimento e aplicação de um modelo para simulação de nitrogênio e fósforo em sistemas de recursos hídricos, que permita simular a interação de rios, reservatórios e áreas agrícolas em termos desses parâmetros de qualidade de água. No arranjo estrutural do modelo desenvolvido, duas etapas metodológicas merecem destaque, são elas: modelagem de nitrogênio e fósforo nas áreas agrícolas, considerando os principais fluxos de entrada e saída desses macronutrientes no solo, e definição dos sistemas de equações diferenciais ordinárias que possam representar a dinâmica comportamental de nitrogênio e fósforo nos corpos hídricos, ou seja, rios e reservatórios integrantes de um determinado sistema estudado. Como estudo de caso, foi selecionado um sistema de recursos hídricos localizado na unidade de planejamento hidrológico do Alto Piranhas-PB, compreendendo áreas agrícolas, rios e reservatórios, juntamente com as principais contribuições de nutrientes para o respectivo sistema, além de ser levado em consideração o aporte das águas da transposição do rio São Francisco, proveniente do Eixo Norte da transposição. Para a aplicação do modelo desenvolvido, foram analisados cenários que possibilitassem uma melhor avaliação da resposta do sistema estudado ao lançamento dos efluentes domésticos e agrícolas, além do impacto das águas da transposição. Os resultados das simulações indicaram que os recursos hídricos analisados são sensíveis a ação dos efluentes domésticos e agrícolas, principalmente nos períodos de seca, onde o volume dos reservatórios e vazões nos trechos dos rios são reduzidos. Com o acréscimo das águas da transposição, foram observadas atenuações significativas nos níveis de nitrogênio e fósforo nos corpos hídricos, devido ao maior poderio de diluição dos efluentes proporcionado por esse aporte hídrico, embora foram observados níveis críticos em alguns meses. Desta forma, medidas preventivas e corretivas devem ser adotadas a esse tipo de sistema, de maneira a evitar o comprometimento da biota aquática e dos múltiplos usos as quais as águas estão destinadas. / The release of domestic effluents in aquatic environments without the proper treatment has compromised the water quality of reservoirs and rivers. This becomes even more relevant when, around these surface water bodies, there is an intense agricultural practice, with the use of nitrogen and phosphorus base fertilizers, where the occurrence of rainfall events can generate runoff and return the excess nutrients present in the soil to nearby rivers and reservoirs. Therefore, this work proposed the development and application of a model for simulation of nitrogen and phosphorus in water resources systems, allowing the interaction of rivers, reservoirs and agricultural areas in terms of water quality parameters. In the structural arrangement of the developed model, two methodological steps are worth mentioning: nitrogen and phosphorus modeling in agricultural areas, considering the main input and output flows of these macronutrients in the soil, and definition of the systems of ordinary differential equations that can represent the behavioral dynamics of nitrogen and phosphorus in the water bodies, ie, rivers and reservoirs that are part of a given system studied. As a case study, a water resource system was selected, located in the Alto Piranhas-PB hydrological planning unit, comprising agricultural areas, rivers and reservoirs, together with the main nutrient contributions to the respective system, besides being taken into account the contribution of the waters of the transposition of the São Francisco river, coming from the Eixo Norte of the transposition. For the application of the developed model, scenarios were analyzed to enable a better evaluation of the response of the studied system to the release of domestic and agricultural effluents, besides the impact of the transposition waters. The results of the simulations indicated that the analyzed water resources are sensitive to the action of domestic and agricultural effluents, mainly in periods of drought, where the volume of the reservoirs and flows in the stretches of the rivers are reduced. With the addition of the transposition waters, significant attenuations were observed in the nitrogen and phosphorus levels in the water bodies, due to the higher dilution power of the effluents provided by this water supply, although critical levels were observed in some months. Therefore, preventive and corrective measures should be adopted for this type of system in order to avoid compromising the aquatic biota and the multiple uses to which the waters are destined.
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Aplicação de algoritmos evolucionários à gestão integrada de sistemas de recursos hídricos. / The use of multi-objective evolucionary algorithms in water resource management.André Schardong 20 June 2011 (has links)
Esta tese estudou a aplicação de algoritmos evolucionários na análise multiobjetivo para gestão integrada de sistemas de recursos hídricos, bem como a sua integração à sistemas de suporte a decisão como o SSD AcquaNet e ModSim DSS. Dois algoritmos evolucionários multi-objetivo são desenvolvidos: MoDE-NS e MoPSO-NS e comparados ao NSGA-II. Os algoritmos foram desenvolvidos em forma de Sistema de Otimização que possibilita a análise de problemas multi-objetivo de forma generalizada com foco em sistemas de recursos hídricos. A possibilidade de integração com o SSD AcquaNet e o ModSim DSS via importação de rede de fluxo e a otimização conjunta, são apresentadas e exploradas. Uma ferramenta de visualização gráfica do conjunto de soluções não dominadas é incluída no Sistema de Otimização. Os algoritmos desenvolvidos foram aplicados a problemas de teste padrão para validação através da comparação de seus resultados ao NSGA-II. As possibilidades de aplicação do sistema de otimização e dos algoritmos evolucionários multi-objetivo foram exploradas inicialmente através de análise multi-objetivo do modelo chuva-vazão Smap com dois e cinco objetivos. Em seguida, a análise foi estendida a um sistema de recursos hídricos complexo, o Sistema Cantareira, responsável pelo abastecimento de aproximadamente metade da RMSP, que corresponde à aproximadamente 33 m³/s. A análise foi realizada comparando dois pares de funções objetivos envolvendo custos de energia elétrica, minimização de déficit no atendimento às demandas e minimização do desvio da qualidade da água em relação à Classe de enquadramento no rio Atibaia, a jusante do reservatório Atibainha e Cachoeira. Os resultados apontam que os algoritmos evolucionários multi-objetivo são aptos para aplicação na análise integrada de sistemas de recursos hídricos e representam uma boa alternativa aos métodos denominados clássicos, pelas suas características peculiares discutidas no trabalho. Algumas recomendações quanto ao uso dos algoritmos abordados para análise de problemas multi-objetivo foram apresentados. / This Thesis presents an application of evolutionary algorithms in multi-objective analysis for integrated management of water resources systems and their integration into decision support systems as AcquaNet and ModSim DSS. Two multi-objective evolutionary algorithms are developed: MoDE-NS-NS and MoPSO-NS and compared to NSGA-II. The algorithms are developed in the form of Optimization System which enables generalized multi-objective analysis with a focus on water resources systems. The possibilities for integration with AcquaNet and ModSim DSS, by importing network flow directly from them or by integrated optimization/simulation are also presented. A graphical visualization tool for the set of non-dominated solutions is also included in Optimization System. The algorithms are applied to common test problems set for validation by comparing its results to the NSGA-II. The possibilities of application of the developed Optimization System and multi-objective evolutionary algorithms are initially exploited by multi-objective analysis of a hydrological rainfall-runoff model Smap, with two and five objectives. Then, the analysis is extended to a complex water resources system, the Cantareira System, responsible for supplying nearly half of the Sao Paulo metro area, which corresponds to approximately 33 m³/s. The analysis is done by comparing two pairs of objective functions: minimization of demand shortage versus minimization of pumping cost and minimization of demand shortage versus minimization of the deviation from water quality standards. The results show that the multi-objective evolutionary algorithms are suitable for application to integrated analysis of water resources systems and represent a good alternative to the so called classical methods, for its peculiar characteristics discussed on this thesis. The MoDE-NS and MoPSO-NS developed, outperformed NSGA-II results, by obtaining a better coverage of the Pareto fronts especially on the water resources system case study.
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Fuzzy State Reservoir Operation Models For IrrigationKumari, Sangeeta 18 July 2016 (has links) (PDF)
Efficient management of limited water resources in an irrigation reservoir system is necessary to increase crop productivity. To achieve this, a reservoir release policy should be integrated with an optimal crop water allocation. Variations in hydrologic variables such as reservoir inflow, soil moisture, reservoir storage, rainfall and evapotranspiration must be considered in the reservoir operating policy model. Uncertainties due to imprecision, subjectivity, vagueness and lack of adequate data can be handled using the fuzzy set theory. A fuzzy stochastic dynamic programming (FSDP) model with reservoir storage and soil moisture of the crops as fuzzy state variables and inflow as a stochastic variable, is developed to obtain a steady state reservoir operating policy. The model integrates the reservoir operating policy with the crop water allocation decisions by maintaining the storage continuity and the soil moisture balance. The reservoir release decisions are made in the model in 10-day periods and water is allocated to the crops on a daily basis. On comparison with the classical stochastic dynamic programming (SDP) model and a conceptual operation policy model, it is observed that the FSDP model, in general, results in lower release from the reservoir while maintaining lower soil moisture stress. However the steady state reservoir operation policy obtained using the FSDP model may not perform well in a short-term reservoir simulation. A fuzzy state short-term reservoir operation policy model with storage and soil moistures of the crops as fuzzy variables, is developed to obtain a real time release policy using forecasted inflow and forecasted rainfall. The distinguishing features of the model are accounting for (a) spatial variation of soil moisture and rainfall using gridded rainfall forecasts and (b) ponding depth requirement of the Paddy. On comparison with a conceptual operation policy model, the fuzzy state real time operation model is found most suitable for the application of the short term real time operation for irrigation. The real time operation model maintains high storage in the reservoir during most of the 10-day time periods of a year and results in a slightly lower annual releases as compared to the conceptual operation policy model. The effect of inflow forecast uncertainty is examined using different sets of forecasted inflows, and it is observed that the system performance is quite sensitive to inflow forecast uncertainties. The use of the satellite based gridded soil moisture in the real time operation model shows consideration of realistic situations. Further, three performance measures, viz., fuzzy reliability, fuzzy resiliency and fuzzy vulnerability are developed to evaluate the performance of the irrigation reservoir system under a specified operating policy. A fuzzy set with an appropriate membership function is defined to describe the working and failed states to account for the system being in partly working and partly failed state. The degree of failure of the irrigation reservoir system is defined based on the evapotranspiration deficit in a period. Inclusion of fuzziness in the performance measures enables realistic representation of uncertainties in the state of the system. A case study of Bhadra reservoir system in Karnataka, India is chosen for demonstrating the model applications.
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Assessment of water exploitation indexes based on water accountingPedro Monzonís, María 12 September 2018 (has links)
[EN] New European policies established in the Blueprint (EC, 2012) propose the use of water accounting for the allocation and reservation of water resources. This course correction contrasts with the calculation of water balances that has been used since the last century in Spain for this purpose. According to the European Commission (EC, 2015) the difference between the two approaches is the inclusion of the economic component. This argument is indisputable, but it would also add that both "asset accounts" and the physical supply and use tables require a type of information that had not been considered until now. In view of this new challenge, the use of hydrological and water resources management models is essential.
This thesis aims to implement a methodology for the transition between water balances and water accounting considering the special characteristics of the Mediterranean basin (with a high degree of regulation and the use of unconventional resources). In the same line, it raises the need for the definition of an indicator to assess the performance of a water resources system taking into consideration the origin of the water resources as a measure of the degree of stress suffered by the systems.
This thesis is presented by publications and seeks to address the methodologies and indicators used to date in the planning and management of water resources. First, the state of the art is analyzed in the first publication of the thesis, as detailed in Annex 1. The second publication, analyzes the key elements for formulating water balances that will determine, to a large extent, results obtained, as detailed in Annex 2. The third publication, in Annex 3, tries to explain how in those basins where the use of water resources is close, or even higher, to their availability, the use of balances based solely on variables such as rainfall and temperature are not sufficient. And due to the high regulation of water resources they should also include the results of water management models. This approach contrasts with the proposals made by the countries of northern Europe focused mainly on hydrological models.
In order to address the water accounting approach a pilot case located in the Andalusian Mediterranean basins was analysed. This work is presented in the fourth publication, reproduced in Annex 4. This initial analysis has served to highlight the need to develop a complementary software that allows unify the results of hydrological and water management models for calculating water accounts. The development of this software, which has been called AQUACCOUNTS, and its application to a general case with all the detail required in water resources planning has been published in the fifth article presented in Annex 5, taking the Júcar River Basin as a case study. From these results, a classification of water exploitation systems was carried out according to their degree of stress. These results were compared with the ones in Annex 2 which proposes the use of the indicator of exploitable water resources and which has been obtained with the traditional water balances approach.
Finally, Annex 6 includes the last publication of this thesis focused on the effects of climate change in the Po River Basin (Italy) by using water accounting. This work has served to identify those key elements within the simulation models and opens the door to improve them within the approach proposed by the SEEA-W.
This thesis aims to collaborate with those responsible for European policies in water resource planning for the application of those methodologies and tools appropriate to each territory. / [ES] Las nuevas políticas europeas establecidas en el Blueprint (EC, 2012) proponen el uso de la contabilidad del agua para la asignación y reserva de los recursos. Esta corrección del rumbo (cambio de paradigma) contrasta con el cálculo de balances que se ha venido utilizando desde el siglo pasado en España para dicho fin. Según la Comisión Europea (EC, 2015) la diferencia entre ambos planteamientos se halla en la inclusión de la componente económica. Este argumento es indiscutible, pero habría que añadir además que tanto las "asset accounts" como las tablas físicas de uso y suministro requieren un tipo de información que hasta ahora no se había considerado. A la vista de este nuevo reto, el uso de los modelos hidrológicos y de gestión de los recursos hídricos se hace imprescindible.
Con esta tesis se pretende llevar a cabo una metodología que permita la transición entre los balances hídricos y las cuentas del agua teniendo en cuenta las especiales características de las cuencas mediterráneas (con un elevado grado de regulación y el uso de recursos no convencionales). En esta misma línea se plantea la definición de un indicador que trate de discutir el comportamiento conjunto de un sistema de recursos hídricos y que tenga en consideración el origen de los recursos empleados como medida del grado de estrés de los sistemas.
Esta tesis se presenta por compendio de publicaciones y trata de abordar las metodologías e indicadores utilizados hasta la fecha en la planificación y gestión de los recursos hídricos. En primer lugar se analiza el estado del arte que constituye la primera publicación de la tesis, tal y como se detalla en el Anexo 1. La segunda publicación, analiza los elementos clave para la formulación de balances que determinarán, en gran medida, los resultados obtenidos, tal y como se detalla en el Anexo 2. La tercera publicación, en el Anexo 3, trata de explicar cómo en las cuencas donde el aprovechamiento de los recursos es cercano o incluso superior a su disponibilidad, el uso de los balances basados únicamente en variables como la precipitación y la temperatura no son suficientes, sino que debido a la alta regulación de los recursos debe recurrirse además a los modelos de gestión. Este planteamiento contrasta con las propuestas planteadas por los países del norte de Europa centrados principalmente en los modelos hidrológicos.
Para abordar el tema se ha partido de un caso piloto localizado en las cuencas mediterráneas andaluzas. Este trabajo se presenta en la cuarta publicación, que se reproduce en el Anexo 4. A partir de este análisis inicial, se vio la necesidad de desarrollar un software complementario que permitiese unificar tanto la información de partida como los resultados de los modelos hidrológicos y de gestión para el cálculo de la contabilidad del agua. El desarrollo de este software, que ha sido denominado AQUACCOUNTS, y su aplicación a un caso general con todo el detalle requerido en planificación se ha publicado en el quinto artículo que se presenta en el Anexo 5, siendo la Demarcación Hidrográfica del Júcar el caso de estudio. A partir de los resultados obtenidos se ha llevado a cabo una clasificación de los sistemas de explotación según su grado de desarrollo comparándose con los resultados obtenidos en el Anexo 2 que propone el uso del indicador de recursos explotables y que se ha obtenido con las metodologías tradicionales de balances.
Por último, el Anexo 6 recoge la última publicación de esta tesis en la que se analizan los efectos del cambio climático en la cuenca del río Po (Italia) mediante el uso de la contabilidad del agua. Este trabajo ha servido para identificar aquellos elementos clave dentro de los modelos de simulación y abre las puertas a una mejora de los mismos dentro del enfoque planteado por el SEEA-W.
Esta tesis pretende colaborar con los responsables de las políticas europeas en materia de planificación para la apl / [CAT] Les noves polítiques europees establides en el Blueprint (EC, 2012) proposen l'ús de la comptabilitat de l'aigua per a l'assignació i reserva dels recursos hídrics. Esta correcció del rumb (o canvi de paradigma) contrasta amb el càlcul de balanços que s'ha utilitzat des del segle passat a Espanya per a aquesta finalitat. Segons la Comissió Europea (EC, 2015) la diferència entre ambdós plantejaments es troba en la inclusió de la component econòmica. Este argument és indiscutible, però caldria afegir a més que tant les "asset accounts" com les taules físiques d'ús i subministrament requerixen un tipus d'informació que fins ara no s'havia considerat. A la vista d'este nou repte, l'ús dels models hidrològics i de gestió dels recursos hídrics es fa imprescindible.
Amb esta tesi es pretén dur a terme una metodologia que permeta la transició entre els balanços hídrics i els comptes de l'aigua tenint en compte les especials característiques de les conques mediterrànies (amb un elevat grau de regulació i l'ús de recursos no convencionals). En esta mateixa línia es planteja la definició d'un indicador que tracte de discutir el comportament conjunt d'un sistema de recursos hídrics i que tinga en consideració l'origen dels recursos empleats com a mesura del grau d'estrés dels sistemes.
Esta tesi es presenta per compendi de publicacions i tracta d'abordar les metodologies i indicadors utilitzats fins a la data en la planificació i gestió dels recursos hídrics. En primer lloc s'analitza l'estat de l'art que constituïx la primera publicació de la tesi, tal com es detalla en l'Annex 1. La segona publicació, analitza els elements clau per a la formulació de balanços que determinaran, en gran manera, els resultats obtinguts, tal com es detalla en l'Annex 2. La tercera publicació, en l'Annex 3, tracta d'explicar com en les conques on l'aprofitament dels recursos és pròxim o inclús superior a la seua disponibilitat, l'ús dels balanços basats únicament en variables com la precipitació i la temperatura no són suficients, sinó que a causa de l'alta regulació dels recursos ha de recórrer-se a més als models de gestió. Este plantejament contrasta amb les propostes plantejades pels països del nord d'Europa centrats principalment en el models hidrològics.
Per a abordar el tema s'ha partit d'un cas pilot localitzat en les conques mediterrànies andaluses. Este treball es presenta en la quarta publicació, que es reproduïx en l'Annex 4. A partir d'aquest anàlisi inicial, es va veure la necessitat de desenrotllar una ferramenta complementaria que permetera unificar tant la informació de partida com els resultats dels models hidrològics i de gestió per al càlcul de la comptabilitat de l'aigua. El desenrotllament d'esta ferramenta, que ha sigut denominat AQUACCOUNTS, i la seua aplicació a un cas general amb tot el detall requerit en planificació s'ha publicat en el quint article que es presenta en l'Annex 5, sent la Demarcació Hidrogràfica del Xúquer el cas d'estudi. A partir dels resultats obtinguts s'ha dut a terme una classificació dels sistemes d'explotació segons el seu grau de desenrotllament comparant-se amb els resultats obtinguts en l'Annex 2 que proposa l'ús de l'indicador de recursos explotables i que s'ha obtingut amb les metodologies tradicionals de balanços.
Finalment, l'Annex 6 arreplega l'última publicació d'esta tesi en què s'analitzen els efectes del canvi climàtic en la conca del riu Po (Itàlia) per mitjà de l'ús de la comptabilitat de l'aigua. Este treball ha servit per a identificar aquells elements clau dins dels models de simulació i obri les portes a una millora dels mateixos dins de l'enfocament plantejat pel SEEA-W.
Esta tesi pretén col·laborar amb els responsables de les polítiques europees en matèria de planificació per a l'aplicació d'aquelles metodologies i ferramentes més adequades a cada territori. / Pedro Monzonís, M. (2016). Assessment of water exploitation indexes based on water accounting [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/71677 / TESIS
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Aplicação de técnicas de programação linear e extensões para otimização da alocação de água em sistemas de recursos hídricos, utilizando métodos de pontos interiores. / Application of linear programming techniques and extensions for optimization of water allocation in water resource systems, using interior points methods.Schardong, André 13 April 2006 (has links)
Neste trabalho é apresentada uma ferramenta de otimização para análise de problemas de alocação de água em bacias hidrográficas utilizando técnicas de programação linear e linear por partes, integradas a um modelo de amortecimentos de ondas em canais. A otimização é feita de forma global, com uso de softwares de programação linear baseados nos métodos de pontos interiores. A metodologia de uso do sistema consiste em se obter uma solução ?ótima? para situações de disponibilidade de água insuficiente a todos os usos conflitantes na bacia. A ferramenta está sendo acoplada e incorporada ao AcquaNet, um Sistema de Suporte a Decisões (SSD) para análise de sistemas de recursos hídricos, que utiliza um algoritmo de rede de fluxo afim de otimizar a alocação de água. A formulação utilizando programação linear permite a análise global do sistema e por isso, espera-se melhor aproveitamento da água disponível, seja no menor déficit de atendimento às demandas ou maior armazenamento nos reservatórios. A programação linear com utilização de métodos de pontos interiores é atualmente uma técnica bastante conhecida e bem desenvolvida. Existem vários pacotes computacionais gratuitos com implementações eficientes dos métodos de pontos interiores que motivaram sua utilização neste trabalho. / This work presents an optimization tool for analyzing the problems of water allocation in watersheds by utilizing techniques of linear and piecewise linear programming integrated to a pattern of stream flow routing. The optimization is done in a global way with the usage of linear programming packages based upon the Internal Point Methods. The methodology of the usage consists in the acquirement of an optimal solution for situation of insufficient water availability for all conflicting consumptions from the watershed. The tool is being attached and incorporated to AcquaNet, which is a decision support system (DSS) for analysis of water resources systems that utilizes a network flow algorithm, with the purpose of optimizing the water allocation. The formulation that uses the linear programming leads to the analysis of the system as a whole and for this reason it is expected a better usage of the available water with a lower deficit in the supply or a greater storage in the reservoirs. Linear Programming with Internal Point Methods is nowadays a well known and very well developed technique. There are several computational packages with efficient implementations of the Internal Points Methods freely available, and that, has brought great motivation in its usage in the present work.
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Aplicação de técnicas de programação linear e extensões para otimização da alocação de água em sistemas de recursos hídricos, utilizando métodos de pontos interiores. / Application of linear programming techniques and extensions for optimization of water allocation in water resource systems, using interior points methods.André Schardong 13 April 2006 (has links)
Neste trabalho é apresentada uma ferramenta de otimização para análise de problemas de alocação de água em bacias hidrográficas utilizando técnicas de programação linear e linear por partes, integradas a um modelo de amortecimentos de ondas em canais. A otimização é feita de forma global, com uso de softwares de programação linear baseados nos métodos de pontos interiores. A metodologia de uso do sistema consiste em se obter uma solução ?ótima? para situações de disponibilidade de água insuficiente a todos os usos conflitantes na bacia. A ferramenta está sendo acoplada e incorporada ao AcquaNet, um Sistema de Suporte a Decisões (SSD) para análise de sistemas de recursos hídricos, que utiliza um algoritmo de rede de fluxo afim de otimizar a alocação de água. A formulação utilizando programação linear permite a análise global do sistema e por isso, espera-se melhor aproveitamento da água disponível, seja no menor déficit de atendimento às demandas ou maior armazenamento nos reservatórios. A programação linear com utilização de métodos de pontos interiores é atualmente uma técnica bastante conhecida e bem desenvolvida. Existem vários pacotes computacionais gratuitos com implementações eficientes dos métodos de pontos interiores que motivaram sua utilização neste trabalho. / This work presents an optimization tool for analyzing the problems of water allocation in watersheds by utilizing techniques of linear and piecewise linear programming integrated to a pattern of stream flow routing. The optimization is done in a global way with the usage of linear programming packages based upon the Internal Point Methods. The methodology of the usage consists in the acquirement of an optimal solution for situation of insufficient water availability for all conflicting consumptions from the watershed. The tool is being attached and incorporated to AcquaNet, which is a decision support system (DSS) for analysis of water resources systems that utilizes a network flow algorithm, with the purpose of optimizing the water allocation. The formulation that uses the linear programming leads to the analysis of the system as a whole and for this reason it is expected a better usage of the available water with a lower deficit in the supply or a greater storage in the reservoirs. Linear Programming with Internal Point Methods is nowadays a well known and very well developed technique. There are several computational packages with efficient implementations of the Internal Points Methods freely available, and that, has brought great motivation in its usage in the present work.
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Swarm Intelligence And Evolutionary Computation For Single And Multiobjective Optimization In Water Resource SystemsReddy, Manne Janga 09 1900 (has links)
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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