Polymer electrolyte membrane fuel cells (PEMFCs) fabricated by direct membrane deposition (DMD) were shown to work even at dry conditions without significant deterioration of the membrane resistance. Here, in situ neutron radiography is used to investigate the water management in those fuel cells to uncover the phenomena that lead to the robust operation under low humidification. A constant level of humidification within the membrane electrode assembly (MEA) of a DMD fuel cell is observed even under dry anode operation and 15% relative humidity on the cathode side. This proves a pronounced back diffusion of generated water from the cathode side to the anode side through the thin deposited membrane layer. Over the entire range of polarization curves a very high similarity of the water evolution in anode and cathode flow fields is found in spite of different humidification levels. It is shown that the power density of directly deposited membranes in contrast to a 50 μm thick N-112 membrane is only marginally affected by dry operation conditions. Water profiles in through-plane direction of the MEA reveal that the water content in the DMD fuel cell remains steady even at high current densities. This is in contrast to the N-112 reference fuel cell which shows a strong increase in membrane resistance and a reduced MEA water content with raising current densities. Thus this new MEA fabrication technique has a promising perspective, since dry operation conditions are highly requested in order to reduce fuel cell system costs.

This diploma thesis deals with analysis of small water reservoirs and their water management. The work is divided into two parts. The first part contains research and the second one is dedicated to the project of small water reservoir. The research describes the basic division of small water reservoir and their construction and technical equipage. The knowledge that has been found is applied in the project. The project describes the renovation of small water reservoir Kančí obora and pool, in k.ú Nové Bránice and Moravský Krumlov.

The diploma thesis is focused on verifying the success of prediction models mean monthly flows for strategy control storage function of water management system. The success of prediction models is tested during three different periods. To determine the predicted inflows into the reservoirs is applied to the generator artificial flow series LTMA using the Monte Carlo method and the classical model of neuron networks. During the solution is applying the principles of adaptive control. The adaptive control is compared with simple control for improved outflow.

The diploma sthesis is focused on verifying the influence of the length of the prediction period and the accuracy of the predicted mean monthly inflows of water sources in the management of hydropower function selected water management system. To determine the predicted inflows into the reservoir system is applied zonal prediction model. When the solution is used a simulation model that is hand-built in Microsoft Excel and optimization model, which is automatically built into the program SOMVS and is applying the principles of adaptive control.

Czech Republic is called roof of the Europe, several rivers rise here and many of them flow away and continue to other countries. That's why I find, that’s extremely important to manage out water sources properly and carefully, because for example the weather has a huge impact on our limited sources and can affect them especially in a dry periods. These issues can be improved by finding a use for used water, good storm water management as well as using greywater. In my diploma thesis, I'll be mainly focused on an overall water management in an ordinary family house. It has two parts as theoretical part and practical part. The theoretical part is then split into another three parts. The first part covers a storm water management, the second is about waste water management. The third explains greywater management. In practical part of my diploma thesis, there's my study of not disposing rain water into a drain with other waste water, but making both waters useful. In this my particular subject in village called Plesnice, is projected a waste water treatment plant. Treated water will be accumulate together with rain water. Accumulated water will be used for irrigation. For a waste water treatment is projected a constructed wetland with vertical flow (down flow reed beds) and facility for sludge management. This is example of extensive technology. Irrigation system consists of storage tank with mechanical pre-treatment and pump valve shaft, sprinklers for lawns, drip irrigation decorative surfaces and everything is controlled by a control unit. Thanks to irrigation and rainwater remains in effect, which is important for local microclimate and save drinking water. This study is an example of that in water management is not necessarily a need for global action, but you can start with individuals and individual houses, which in total could have a significant effect on water retention in the landscape and to slow down and reduce the peak flow in rivers.

Cette thèse analyse les organisations et les relations sociales qui façonnent les usages de l'eau dans la plaine de la Crau. L'approche inductive et multi-échelle explore les interactions entre acteurs humains et non-humains qui participent au gouvernement et aux pratiques de l'eau. Le travail de terrain s'est focalisé sur les dynamiques de modernisation de l’eau en Crau sur les deux derniers siècles et notamment sur celles de gestion intégrée de l’eau. Un travail d’archives historiques et contemporaines permet de situer les continuités et les discontinuités des formes de gouvernement de l'eau. Une enquête par entretiens et l’observation de réunions professionnelles ou publiques nourrit la réflexion sur les jeux d'acteurs actuels. Les généalogies, le fonctionnement des dispositifs de gouvernement ainsi que les arrangements, contournements ou oppositions qu'ils suscitent, sont analysés dans une perspective constructiviste et historique. Il s’agit ainsi d’une contribution à une political ecology du « premier monde », croisant une approche latourienne avec une étude des manières de gouverner foucaldienne.L’eau en Crau est un objet multifacette sujet à une pluralité d’appropriations. L'irrigation gravitaire de 12 000 hectares de prairies de foin de Crau repose sur un réseau de canaux dérivant l'eau de la Durance depuis 1554, alimenté depuis 1972 par l’aménagement hydro-électrique. L’arrosage établit ainsi une frontière entre la Crau sèche des Coussouls et la Crau humide « productive ». La nappe de Crau est rechargée à plus de 70% par les infiltrations dues à ces pratiques d’arrosage. Depuis les années 1970, le développement industriel, l'agriculture intensive et l'urbanisation ont conduit à une exploitation croissante de cette nappe. Elle approvisionne actuellement 270 000 habitants et est considérée comme vulnérable, notamment du fait de son alimentation dépendante de la production de foin. La nappe fait ainsi l'objet de dispositifs de gestion destinés à protéger la ressource par une démarche territoriale.L’étude de l’articulation des savoirs techno-scientifiques spécifiques avec les manières de gouverner l’eau dans le temps long met en lumière un réseau hétérogène d'êtres et d'objets qui ont interagit pour moderniser l’eau. La « modernité » s'entend ici comme un idéal émancipateur fondé sur une augmentation de l'objectivité, de l'efficacité, de la rentabilité et de la formalisation (Latour, 2004). Cette recherche analyse comment les différentes manières de moderniser l’eau transforment la matérialité même de l'eau. L’étude des constructions matérielles, symboliques ou encore normatives qui sous-tendent et territorialisent les dispositifs de modernisation du gouvernement de l’eau est associée à celle des arrangements, des adaptations et des résistances qu'ils produisent en retour. C'est dans cette tension entre les façons de gouverner et les façons de faire que se situe le cœur et l'apport empirique de la thèse.Trois vagues de modernisation de l’eau sont identifiées à partir du cas de la Crau. A la suite de la Révolution Française, la première vague vise à conquérir et «mettre en valeur» la Crau. L’Etat impose ainsi progressivement un règlement des eaux et soutient la mise en culture des Coussouls par des acteurs privés. Dans les années 1950, la deuxième vague est mise en œuvre pour reconstruire la France. Elle porte un discours d’abondance hydraulique. Depuis les années 1990, une troisième vague met l’accent sur la rareté de l’eau et la vulnérabilité de ses usages et appelle à leur gestion intégrée. La vivisection du dispositif de gestion de la nappe de Crau permet d’explorer son fonctionnement dans son versant formel comme ses pratiques informelles. Les discours de crise de l’eau se révèlent partie intégrante de la gestion. Ils sont déployés pour mobiliser des acteurs historiques et des usagers, les enrôlant dans une nouvelle gouvernementalité avec laquelle ils doivent composer. / This thesis analyzes the institutions and the social relations which shape water use in the Crau plain. The inductive and multi-scale approach explores the interactions between human and non-human actors that contribute to water governmance and practices. The fieldwork focused on the dynamics of modernization in water over the last two centuries and particularly on moves toward integrated water management. Archival work drawing on historical and contemporary sources makes it possible to identify the continuities and discontinuities in manners to govern water. Interviews and the observation of meetings, both professional and public, provide insights into the actual interplay among actors. The genealogy and functioning of governing apparatuses, as well as the ways in which they are adapted, circumvented or opposed in turn, are analyzed using a constructivist and historical perspective. This work thus contributes to a political ecology of the first world by bringing together a Latourian approach with a Foucauldian study of governing manners.Water in the Crau is a multifaceted object appropriated in a number of different ways. the gravity-fed irrigation of 12 000 ha of grassland producing hay in the Crau relies on a canal network that has derived water from the Durance since 1554, and has been supplied since 1972 by the hydroelectric infrastructure. This has resulted in a frontier between the dry Crau (Coussouls) and the “productive” wet Crau. These irrigation practices account for 70% of the volume of the groundwater table. Since the 1970s, industrial development, intensive agriculture and urban expansion have led to an increasing exploitation of groundwater. This water sustains 270 000 inhabitants and is considered vulnerable, particularly as it is artificially sustained by hay production. The groundwater is subject to management apparatuses that aim to protect the resource through a territorial approach.The long term study of the articulation of specific techno-scientific knowledge and manners to govern water highlight the heterogeneous network of actors and objects that interact to modernize water. “Modernity” is understood as an emancipatory ideal based on increased objectivity, efficacy, profitability and formalism (Latour, 2004). This research analyzes how the different manners to modernize water transform the materiality of water itself. The study of material, symbolic or normative constructions underpinning and territorializing the modernization apparatuses of water governance is complemented by the study of arrangements, adaptations and resistance that they generate in turn. The heart of this study, and its empirical contribution, lie in this tension between governing manners and everyday practices.Three waves of modernization of water have been identified from the grounded perspective of the Crau. Following the French Revolution, the first wave aimed to conquer and to improve the Crau. The state progressively imposed water regulation and supported the cultivation of Coussouls by private actors. In the 1950s, the second wave, implemented as part of a project to reconstruct France, emphasized hydraulic abundance. Since the 1990s, a third wave has highlighted the scarcity of water and the vulnerability o users, and called for integrated management. The vivisection of apparatuses of groundwater management considers its functioning in both its formal aspect and informal practices. Discourses of water crises reveal themselves as an integral part of water management. They are deployed to mobilize historical actors and users, by integrating them in a new governmentality within which they have to work.

Im Rahmen wasserwirtschaftlicher Planungen ist eine Vielzahl unterschiedlicher Zielsetzungen zu berücksichtigen. Diese ergeben sich u. a. aus den Vorgaben der EU-Wasserrahmenrichtlinie (EUWRRL), dem Leitbild einer nachhaltigen Landnutzung, dem Hochwasserschutz und der Freizeitnutzung. In der Praxis ist die Umsetzung dieser Ziele eine anspruchsvolle Aufgabe, für die geeignete Hilfsmittel entwickelt werden müssen. Zu diesem Zweck unterstützte die Deutsche Bundesstiftung Umwelt (DBU) für drei Jahre (06/2002 - 06/2005) ein Verbundprojekt zur Entwicklung von „Verbesserten Ansätzen für Wasser- und Stoffstrommanagement in intensiv genutzten kleinen Einzugsgebieten auf der Grundlage von integrierten Nutzen- und Risikobewertungen (wsm300)“.

Increasing population and water conflicts are making water management one of the most important issues of the present world. It has become absolutely necessary to find ways to manage water more efficiently. Technological advancement has introduced various techniques for data acquisition and analysis, and these tools can be used to address some of the critical issues that challenge water resource management. This research used learning machine techniques and information acquired through remote sensing, to solve problems related to soil moisture estimation and crop identification on large spatial scales. In this dissertation, solutions were proposed in three problem areas that can be important in the decision making process related to water management in irrigated systems. A data assimilation technique was used to build a learning machine model that generated soil moisture estimates commensurate with the scale of the data. The research was taken further by developing a multivariate machine learning algorithm to predict root zone soil moisture both in space and time. Further, a model was developed for supervised classification of multi-spectral reflectance data using a multi-class machine learning algorithm. The procedure was designed for classifying crops but the model is data dependent and can be used with other datasets and hence can be applied to other landcover classification problems. The dissertation compared the performance of relevance vector and the support vector machines in estimating soil moisture. A multivariate relevance vector machine algorithm was tested in the spatio-temporal prediction of soil moisture, and the multi-class relevance vector machine model was used for classifying different crop types. It was concluded that the classification scheme may uncover important data patterns contributing greatly to knowledge bases, and to scientific and medical research. The results for the soil moisture models would give a rough idea to farmers/irrigators about the moisture status of their fields and also about the productivity. The models are part of the framework which is devised in an attempt to provide tools to support irrigation system operational decisions. This information could help in the overall improvement of agricultural water management practices for large irrigation systems. Conclusions were reached based on the performance of these machines in estimating soil moisture using remotely sensed data, forecasting spatial and temporal variation of soil moisture and data classification. These solutions provide a new perspective to problem–solving techniques by introducing new methods that have never been previously attempted.

Tesis por compendio / [EN] First chapter uses California's drought to identify the economic threats of water scarcity on food, energy and environmental systems as a way to introduce the multiple interactions between these resources. The second part of this first chapter introduces the focus of the dissertation, the water-energy nexus, presents a literature review identifying gaps, states the main and specific research objectives and the research questions, explains the research approach, and describes the organization of the dissertation. Second chapter develops an end-use model for water use and related energy and carbon footprint using probability distributions for parameters affecting water consumption in 10 local water utilities in California. Statewide single-family water-related CO2 emissions are 2% of overall per capita emissions, and locally variability is presented. The impact of several common conservation strategies on household water and energy use are assessed simulating different scenarios. Based on the this model, Chapter 3 introduces a probabilistic two-stage optimization model considering technical and behavioral decision variables to obtain the most eco-nomical strategies to minimize household water and water-related energy bills and costs given both water and energy price shocks. Results can provide an upper bound of household savings for customers with well-behaved preferences, and show greater adoption rates to reduce energy intensive appliances when energy is accounted, result-ing in an overall 24% reduction in indoor water use that represents a 30 percent reduc-tion in water-related energy use and a 53 percent reduction in household water-related CO2 emissions. To complete the urban water cycle, Chapter 4 develops first an hourly model of urban water uses by customer category including water-related energy consumption and next I calibrate a model of the energy used in water supply, treatment, pumping and wastewater treatment by the utility, using real data from East Bay Municipal Utility District in California. Hourly costs of energy for the water and energy utilities are assessed and GHG emissions for the entire water cycle estimated. Results show that water end-uses account for almost 95% of all water-related energy use, but the 5% managed by the utility is still worth over $12 million annually. Several simulations analyze the potential benefits for water demand management actions. The total carbon footprint per capita of the urban water cycle is 405 kg CO2/year representing 4.4% of the total GHG emissions per capita in California. Accounting for the results obtained in Chapters 2 to 4, Chapter 5 describes a simple but powerful decision support system for water management that includes water-related energy use and GHG emissions not solely from the water operations, but also from final water end uses, including demands from cities, agriculture, environment and the energy sector. The DSS combines a surface water management model with a simple groundwater model, accounting for their interrelationships, and also includes explicitly economic data to optimize water use across sectors during shortages and calculate return flows from different uses. Capabilities of the DSS are demonstrated on a case study over California's intertied water system over the historic period and some simulations are run to highlight water and energy tradeoffs. Results show that urban end uses account for most GHG emissions of the entire water cycle, but large water conveyance produces significant peaks over the summer season. The carbon footprint of the entire water cycle during this period, according to the model, was 21.43 millions of tons of CO2/year, what was roughly 5% of California's total GHG emissions. The last two chapters discus and summarize the thematic and methodological contribu-tions and looks for further research presenting and discussing the research gaps and research questions that this dissertation left open. / [ES] El primer capítulo utiliza la sequía de California para identificar las amenazas económicas de la escasez de agua en los sistemas de producción de alimentos, energético y medioambiental para presentar las múltiples interacciones entre estos recursos. La segunda parte del primer capítulo centra el objetivo de la tesis, la relación entre el agua y la energía, presenta la revisión de la literatura identificando los vacíos, describe los objetivos y las cuestiones que busca responder esta investigación, explica la metodología seguida, y describe la organización de la tesis. En el segundo capítulo se desarrolla un modelo de usos finales de agua, contando con la energía y las emisiones de GEI asociados utilizando distribuciones de probabilidad para los parámetros que afectan al uso del agua en 10 ciudades en California. Como resultados principales se obtiene que las emisiones de GEI asociadas al consumo residencial de agua representan el 2% del total de emisiones per cápita, y se presenta la variabilidad debida a las condiciones locales. Los impactos de algunas prácticas comunes de ahorro de agua y energía son calculadas simulando diferente escenarios. Basado en ese modelo, el Capítulo 3 se presenta un modelo de optimización probabilísticos en dos periodos considerando variables de decisión de modificaciones técnicas y de comportamiento en relación al consumo de agua para obtener las estrategias más económicas para minimizar las facturas de agua y energía. Los resultados proporcionan un límite superior para el ahorro doméstico, y muestran mayores tasas de adopción para reducir usos de agua que son más intensivos en consumo energético cuando la energía se incluye, resultando en una reducción del 24% de uso de agua adentro de las casas, que representa un 30% en reducción de energía y un 53% de emisiones de GEI, ambos relacionados con el consumo de agua. Para completar el ciclo urbano del agua, el Capítulo 4 desarrolla primero un modelo horario de usos de agua incluyendo la energía asociada y después se calibra un modelo de agua y energía en el abastecimiento, tratamiento y bombeo de agua, y el tratamiento de agua residual, utilizando datos reales de East Bay Municipal Utility District en California. Los costes horarios de energía para las compañías de agua y energía, así como las emisiones de GEI son estimadas. Los resultados muestran que los usos finales son responsables del 95% de la energía relacionada con el uso del agua, pero que el 5% restante tiene un coste de 12 millones de dólares anualmente. Teniendo en cuenta los resultados obtenidos en los capítulos 2, 3 y 4, el Capítulo 5 describe un sistema de apoyo de decisión (SSD) para gestión de recursos hídricos incluyente energía y emisiones de GEI no sólo de la gestión del agua, sino también de usos finales del agua, incluyendo demandas urbanas, agrícolas, ambientales y del sector energético. El SSD combina un modelo de agua superficial con uno de agua subterráneo, incluyendo sus interacciones, y también incluye explícitamente datos económicos para optimizar el uso del agua durante periodos de sequía. Las posibilidades del SSD son demostradas en un caso de estudio aplicado a un modelo simplificado del sistema de recursos hídricos de California. Los resultados muestran que los usos finales del agua en zonas urbanas son responsables de la mayoría de las emisiones de GEH, pero que las grandes infrastructures de transporte de agua producen importante picos en verano. De acuerdo con el modelo, la huella de carbón del ciclo del agua en California es de 21.43 millones de toneladas de CO2/año, lo que significa aproximadamente el 5% del total de emisiones de GEI del estado. Los últimos dos capítulos resumen y discuten las contribuciones temáticas y metodológicas de esta tesis, presentando nuevas líneas de investigación que se derivan de este trabajo. / [CA] El primer capítol utilitza la sequera de Califòrnia per a identificar les amenaces econòmiques de l'escassesa d'aigua en els sistemes de producció d'aliments, energètic i mediambiental per a presentar les múltiples interaccions entre estos recursos. La segona part del primer capítol centra l'objectiu de la tesi, la relació entre l'aigua i l'energia, presenta la revisió de la literatura identificant els buits, descriu els objectius i les qüestions que busca respondre esta recerca, explica la metodologia seguida, i descriu la organització de la tesi. Al segon capítol es desenvolupa un model d'usos finals d'aigua, comptant amb l'energia i les emissions de GEH associats utilitzant distribucions de probabilitat per als paràmetres que afecten a l'ús de l'aigua en 10 ciutats en Califòrnia. Com a resultats principals s'obté que les emissions de GEH associades al consum residencial d'aigua representen el 2% del total d'emissions per càpita, i es presenta la variabilitat deguda a les condicions locals. Els impactes d'algunes pràctiques comunes d'estalvi d'aigua i energia són calculades simulant diferent escenaris. Basat en eixe model, al Capítol 3 es presenta un model d'optimització probabilístics en dos períodes considerant variables de decisió de modificacions tècniques i de comportament en relació al consum d'aigua per a obtindre les estratègies més econòmiques per a minimitzar les factures d'aigua i energia. Els resultats proporcionen un límit superior per a l'estalvi domèstic, i mostren majors taxes d'adopció per a reduir usos d'aigua que són més intensius en consum energètic quan l'energia es incluïda, resultant en una reducció del 24% d'ús d'aigua a dins de les cases, que representa un 30% en reducció d'energia i un 53% d'emissions de GEH, ambdós relacionats amb el consum d'aigua. Per a completar el cicle urbà de l'aigua, el Capítol 4 desenvolupa primer un model horari d'usos d'aigua incloent l'energia associada i després es calibra un model d'aigua i energia en l'abastiment, tractament i bombeig d'aigua i al tractament d'aigua residual, utilitzant dades reals de East Bay Municipal Utility District en Califòrnia. Els costs horaris d'energia per a les companyies d'aigua i energia, així com les emissions de GEH són estimades. Els resultats mostren que els usos finals són responsables del 95% de l'energia relacionada amb l'ús de l'aigua, però que el 5% restant té un cost de 12 milions de dolars anualment. Algunes simulacions analitzen els beneficis econòmics potencials de mesures de gestió de demanda d'aigua. La petjada de carbó total del cicle urbà de l'aigua s'estima en 405 kg CO2/any representant el 4.4% de les emissions per càpita en Califòrnia. Tenint en compte els resultats obtesos en els capítols 2, 3 i 4, el Capítol 5 descriu un sistema de suport de decisió (SSD) per a gestió de recursos hídrics incloent energia i emissions de GEH no sols de la gestió de l'aigua, sinó també del úsos finals de l'aigua, incloent demandes urbanes, agrícoles, ambientals i del sector energètic. El SSD combina un model d'aigua superficial amb un d'aigua subterrànea, incloent les seues interrelacions, i també inclou explícitament dades econòmiques per a optimitzar l'ús de l'aigua durant períodes de sequera. Les possibilitats del SSD són demostrades en un cas d'estudi aplicat a un model simplificat del sistema de recursos hídrics de Califòrnia. Els resultats mostren que els usos finals de l'aigua en zones urbanes són responsables de la majoria de les emissions de GEH, però que les grans infrastructures de transport d'aigua produïxen important pics a l'estiu. D'acord amb el model, la petjada de carbó del cicle de l'aigua a Califòrnia és de 21.43 milions de tones de CO2/any, el que significa aproximadament el 5% del total d'emissions de GEH a l'estat. Els últims dos capítols resumeixen i discuteixen les contribucions temàtiques i metodològiques d'esta tesi, presentan / Escrivà Bou, À. (2015). The Water-Energy Nexus: a bottom-up approach for basin-wide management [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59451 / TESIS / Premios Extraordinarios de tesis doctorales / Compendio

This diploma thesis deals with sound water management and is divided into theoretical and practical part. The theoretical part is divided into three main chapters. The first part focuses on rainwater, its quality characteristics and utilization. The second chapter focuses on the management of waste water, its properties, the amount of waste water and natural ways of wastewater treatment. The last chapter is devoted to the gray waters and their utilization. The practical part focuses on the study of the draft comprehensive management of sewage and rainwater in the village Pařezov district Domažlice. It focuses on wastewater treatment using constructed wetlands, using rainwater for irrigation and infiltration of the remaining water.