Dissertations / Theses on the topic 'Water control'
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Wang, Zhong. "Adaptive water quality control in drinking water distribution." Cincinnati, Ohio : University of Cincinnati, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=1052325491.
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WANG, ZHONG. "ADAPTIVE WATER QUALITY CONTROL IN DRINKING WATER DISTRIBUTION NETWORKS." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1052325491.
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Root, Christopher Wayne. "Stylistic control of ocean water simulations." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2373.
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Bozkurt, Okan Cagri. "Operation Of The Water Control Structures." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615419/index.pdf.
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Floods are one of the most important natural disasters regarding damages caused by them. Major reasons of huge damages of floods are unplanned urbanization, narrowing of river beds and incorrect operation of water control structures. Geographic Information Systems (GIS) can provide important tools to be used in flood modeling studies. In this study, Lake Mogan, Lake Eymir and Incesu Detention Pond subbasins are studied for flooding events within GIS framework. These subbasins are important catchment areas of city of Ankara with total drainage area of 1070 km2. Soil Conservation Service (SCS) method is used to obtain flood hydrographs for 12 hour duration and 50, 100 and 500 year return periods. Flood routing procedure is applied to obtain discharges at the outlet of the Mogan and Eymir Lakes and Incesu Detention Pond. Operation performance of water control structures are tried to be estimated by using hydrographs which are obtained for different scenarios. Results show that elements of Lake Mogan Water Control Structure do not have capability to discharge 500 year storm safely to the downstream of the lake. However, 100 year storm can be routed without creating problem if necessary small precautions are taken. On the other hand, water control elements of Lake Eymir and Incesu Detention Pond can transmit obtained flood volumes to the downstream parts by assuming that closed conduit at the exit of Incesu Detention Pond can safely convey resultant flood discharges.
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Safronova, D. "Biological method for water quality control." Thesis, Видавництво СумДУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/26726.
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Problem
Saint-Petersburg is located at the Neva river and almost all drinking water for 5 million inhabitants is taken from it. Talking about water supply centralised source for Saint-Petersburg, one can mark a lot of negative factors influencing the water quality. Surely, agricultural pollution, transport and economical problems are among them.
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Riquelme, Victor. "Optimal control problems for bioremediation of water resources." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT290/document.
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Cette thèse se compose de deux parties. Dans la première partie, nous étudions les stratégies de temps minimum pour le traitement de la pollution dans de grandes ressources en eau, par exemple des lacs ou réservoirs naturels, à l'aide d'un bioréacteur continu qui fonctionne à un état quasi stationnaire. On contrôle le débit d'entrée d'eau au bioréacteur, dont la sortie revient à la ressource avec le même débit. Nous disposons de l'hypothèse d'homogénéité de la concentration de polluant dans la ressource en proposant trois modèles spatialement structurés. Le premier modèle considère deux zones connectées l'une à l'autre par diffusion et seulement une d'entre elles connectée au bioréacteur. Avec l'aide du Principe du Maximum de Pontryagin, nous montrons que le contrôle optimal en boucle fermée dépend seulement des mesures de pollution dans la zone traitée, sans influence des paramètres de volume, diffusion, ou la concentration dans la zone non traitée. Nous montrons que l'effet d'une pompe de recirculation qui aide à homogénéiser les deux zones est avantageux si opérée à vitesse maximale. Nous prouvons que la famille de fonctions de temps minimal en fonction du paramètre de diffusion est décroissante. Le deuxième modèle consiste en deux zones connectées l'une à l'autre par diffusion et les deux connectées au bioréacteur. Ceci est un problème dont l'ensemble des vitesses est non convexe, pour lequel il n'est pas possible de prouver directement l'existence des solutions. Nous surmontons cette difficulté et résolvons entièrement le problème étudié en appliquant le principe de Pontryagin au problème de contrôle relaxé associé, obtenant un contrôle en boucle fermée qui traite la zone la plus polluée jusqu'au l'homogénéisation des deux concentrations. Nous obtenons des limites explicites sur la fonction valeur via des techniques de Hamilton-Jacobi-Bellman. Nous prouvons que la fonction de temps minimal est non monotone par rapport au paramètre de diffusion. Le troisième modèle consiste en deux zones connectées au bioréacteur en série et une pompe de recirculation entre elles. L'ensemble des contrôles dépend de l'état, et nous montrons que la contrainte est active à partir d'un temps jusqu'à la fin du processus. Nous montrons que le contrôle optimal consiste à l'atteinte d'un temps à partir duquel il est optimal de recirculer à vitesse maximale et ensuite ré-polluer la deuxième zone avec la concentration de la première. Ce résultat est non intuitif. Des simulations numériques illustrent les résultats théoriques, et les stratégies optimales obtenues sont testées sur des modèles hydrodynamiques, en montrant qu'elles sont de bonnes approximations de la solution du problème inhomogène. La deuxième partie consiste au développement et l'étude d'un modèle stochastique de réacteur biologique séquentiel. Le modèle est obtenu comme une limite des processus de naissance et de mort. Nous établissons l'existence et l'unicité des solutions de l'équation contrôlée qui ne satisfait pas les hypothèses habituelles. Nous prouvons que pour n'importe quelle loi de contrôle la probabilité d'extinction de la biomasse est positive. Nous étudions le problème de la maximisation de la probabilité d'atteindre un niveau de pollution cible, avec le réacteur à sa capacité maximale, avant l'extinction. Ce problème ne satisfait aucune des suppositions habituelles (la dynamique n'est pas lipschitzienne, diffusion dégénérée localement hölderienne, contraintes d'état, ensembles cible et absorbant s'intersectent), donc le problème doit être étudié dans deux étapes: en premier lieu, nous prouvons la continuité de la fonction de coût non contrôlée pour les conditions initiales avec le volume maximal et ensuite nous développons un principe de programmation dynamique pour une modification du problème original comme un problème de contrôle optimal avec coût final sans contrainte sur l'étatThis thesis consists of two parts. In the first part we study minimal time strategies for the treatment of pollution in large water volumes, such as lakes or natural reservoirs, using a single continuous bioreactor that operates in a quasi-steady state. The control consists of feeding the bioreactor from the resource, with clean output returning to the resource with the same flow rate. We drop the hypothesis of homogeneity of the pollutant concentration in the water resource by proposing three spatially structured models. The first model considers two zones connected to each other by diffusion and only one of them treated by the bioreactor. With the help of the Pontryagin Maximum Principle, we show that the optimal state feedback depends only on the measurements of pollution in the treated zone, with no influence of volume, diffusion parameter, or pollutant concentration in the untreated zone. We show that the effect of a recirculation pump that helps to mix the two zones is beneficial if operated at full speed. We prove that the family of minimal time functions depending on the diffusion parameter is decreasing. The second model consists of two zones connected to each other by diffusion and each of them connected to the bioreactor. This is a problem with a non convex velocity set for which it is not possible to directly prove the existence of its solutions. We overcome this difficulty and fully solve the studied problem applying Pontryagin's principle to the associated problem with relaxed controls, obtaining a feedback control that treats the most polluted zone up to the homogenization of the two concentrations. We also obtain explicit bounds on its value function via Hamilton-Jacobi-Bellman techniques. We prove that the minimal time function is nonmonotone as a function of the diffusion parameter. The third model consists of a system of two zones connected to the bioreactor in series, and a recirculation pump between them. The control set depends on the state variable; we show that this constraint is active from some time up to the final time. We show that the optimal control consists of waiting up to a time from which it is optimal the mixing at maximum speed, and then to repollute the second zone with the concentration of the first zone. This is a non intuitive result. Numerical simulations illustrate the theoretical results, and the obtained optimal strategies are tested in hydrodynamic models, showing to be good approximations of the solution of the inhomogeneous problem. The second part consists of the development and study of a stochastic model of sequencing batch reactor. We obtain the model as a limit of birth and death processes. We establish the existence and uniqueness of solutions of the controlled equation that does not satisfy the usual assumptions. We prove that with any control law the probability of extinction is positive, which is a non classical result. We study the problem of the maximization of the probability of attaining a target pollution level, with the reactor at maximum capacity, prior to extinction. This problem does not satisfy any of the usual assumptions (non Lipschitz dynamics, degenerate locally H"older diffusion parameter, restricted state space, intersecting reach and avoid sets), so the problem must be studied in two stages: first, we prove the continuity of the uncontrolled cost function for initial conditions with maximum volume, and then we develop a dynamic programming principle for a modification of the problem as an optimal control problem with final cost and without state constraint
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Shang, Feng. "INPUT-OUTPUT WATER QUALITY MODEL IN WATER DISTRIBUTION SYSTEM." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1028649564.
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Chang, Tao. "Robust model predictive control of water quality in drinking water distribution systems." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398894.
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This thesis develops online feedback control of chlorine residuals performing at the lower level of a hierarchical structure of integrated quantity and quality control in drinking water distribution systems (DWDS), which provides a practical solution for online water quality control in DWDS. Input-output and state-space models of the chlorine residuals are developed from mathematical models of chlorine residual dynamics. The existing path analysis algorithm is extended and utilized to obtain the parameter structure. Joint parameter and model structure error estimation is developed using bounding approach based on a point-parametric model. The uncertainty radius of the system is outlined through robust output prediction, through which requirements for model accuracy from robust model predictive control (MFC) are explicitly imposed on model estimation. Hence, an integrated design of controller and model estimation is achieved. MFC is applied for chlorine residual control based on the set-bounded model. To fulfil output constraints under system uncertainties, safety zones are employed, which are designed from an online evaluation of the uncertainty scenarios of the system, to restrict the output constraints. The safety zones can be obtained by solving a nonlinear constrained optimization problem using a significantly simplified relaxation-gain algorithm. The resulting robust MFC (RMPC) is decentralized assuming communication among the decentralized RMPCs is available. The proposed methodology is verified by applying it to a simulated benchmark DWDS. Simulation study of model estimation and RMPC operation is presented and discussed.
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Overloop, Peter-Jules van. "Model predictive control on open water systems /." Amsterdam : IOS Press, 2006. http://opac.nebis.ch/cgi-bin/showAbstract.pl?u20=9781586036386.
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Rodrigues, Maria. "PID Control of Water in a tank." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-9611.
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The thesis assignment was to build a PID control that was able to control two tanks of water. The system had to be capable of read a certain value, the value that we speak is the high of the water. There for, the system should fill the corresponding tank with water, of course, until the high that was chosen. A PID control uses tree essentials values to be able to control with precision, they are usually called: P, I and D. These values can be found by applying some procedures; in this thesis two procedures were applied. So at the end, we get two values for each constant (PID). In this thesis these two values are compared in order to choose which method was the accurate.
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Gabrielsson, Fredrik. "Model Predictive Control of Skeboå Water system." Thesis, KTH, Reglerteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98868.
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This thesis is a study of model predictive control of water levels and flows in a water system. The water system studied includes five lakes and six dams that are regulated manually by sluice-gates. The water is used in the papermaking process at Holmen Paper Mill in Hallstavik. The aim of this thesis is to find out how to control the water system when all dams are automated and to minimize the discharge of water from the system without risking production stops due to water shortage. To fulfil the aim, a simulation is made during a dry period with low amount of rain. The simulation is then compared to the same period but when the system was manually controlled. In this thesis two models of the water system are constructed, a simple linear model and a more complex non-linear model. In the linear model the channels between the lakes are assumed to be delays of water flow. In the non-linear model the same channels are described by Saint Venant equations of changes of flow and Manning’s equation on how water flow and the cross-section of a channel are related. In both models, the lakes are modelled as the change in volume with respect to time due to inflow to and outflow from the lake. The non-linear model is verified against measured water levels, flows, sluice-gate heights and precipitation to ensure that the model describes the water system well enough. The linear model is used in the model predictive controller to calculate the optimal outflow from the dams. The optimal outflows are then converted into optimum gate heights in the dams, which in turn are used as input to the non-linear model. The non-linear model is used to simulate the water system. The results from the simulation show that the control of the water system can significantly be improved. The conclusion of this thesis is that a lot more water can be saved when the system is automated and that the water levels in the lakes can be kept more stable with respect to a set reference level. The recommendation if only one dam is to be controlled initially is to start with the dam at Närdingen.
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Bontrager, Chad. "Flour moisture control for maximum water addition." Thesis, Kansas State University, 2009. http://hdl.handle.net/2097/11973.
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Master of AgribusinessDepartment of Agricultural Economics
Michael Langemeier
This thesis examines flour moisture control and how this control can be an effective tool for cost minimization in a flour mill. Specifically, this thesis discusses the economic rationale behind the value of moisture control, the variables associated with moisture control, options for controlling those variables, the current control strategies, the decision process used to examine moisture control options, analysis of the solution, and implementation of optimal control strategies. In the area of optimal control strategies, two outcomes were generated in the thesis. The first outcome involved collecting data and developing a better understanding of the factors impacting flour moistures. The second outcome was to create a spreadsheet tool for use in the flour mill that would allow operators to determine an optimal water set point that would bring about a desired flour moisture taking into consideration the variables effecting flour moisture and their status at a given time. Both outcomes have been met and are outlined in detail in the thesis. It is understood that the conclusions of this thesis do not represent an end to the flour moisture control challenge and that more research is needed in order to implement further control measures. Work that remains to be done in order to achieve even better moisture control is also outlined in this thesis.
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Martínez, Adriana N., and Oscar E. Defelippe. "Human right to water and conventionality control." Pontificia Universidad Católica del Perú, 2013. http://repositorio.pucp.edu.pe/index/handle/123456789/115348.
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Humanity faces the challenge of achieving the sustainability of water resources supply for the satisfaction of human needs and ofensuring the sustainability of the natural ecosystems for the achievement of sustainable human development and the quality of life of present and future generations. For this reason the recognition of access to water as a Human Right has fundamental significance. We proceed to analyze the international instruments that provide content and legal basis to the human right to water and the obligations of States. In this context, we deal with the constitutional reception of human right to water in Argentina in the constitutional reform of 1994 and the control of conventionality as guarantor of access to water, which has led to different domestic courts to consider cases in which a violation ofthe right to water was proved.La humanidad enfrenta el desafío de lograr la sostenibilidad de la oferta de los recursos hídricos para la satisfacción de las necesidades humanas y garantizar la de los ecosistemas naturales para el logro del desarrollo humano sustentable y la calidad de vida de la generación presente y de las futuras. Es por ello que el reconocimiento del derecho al acceso al agua como derecho humano adquiere primordial relevancia. Procedemos al análisis de los instrumentos internacionales que dan contenido y fundamento jurídico al derecho humano al agua y de los que derivan las obligaciones de los Estados. En ese contexto, abordamos la recepción constitucional del derecho humano al agua en Argentina, a partir de la reforma constitucional de 1994, y al control de convencionalidad como garante del acceso al agua, que ha llevado a que distintos tribunales internos se ocuparan de casos en los que se constató la vulneración del derecho al agua.
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Correia, Daniel Fortuna. "Management and Control of Water Supply Systems." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13834.
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Mestrado em Engenharia MecânicaThe fast increase in the energy’s price has brought a growing concern about the highly expensive task of transporting water. By creating an hydraulic model of the Water Supply System’s (WSS) network and predicting its behaviour, it is possible to take advantage of the energy’s tariffs, reducing the total cost on pumping activities. This thesis was developed, in association with a technology transfer project called the E-Pumping. It focuses on finding a flexible supervision and control strategy, adaptable to any existent Water Supply System (WSS), as well as forecasting the water demand on a time period chosen by the end user, so that the pumping actions could be planned to an optimum schedule, that minimizes the total operational cost. The OPC protocol, associated to a MySQL database were used to develop a flexible tool of supervision and control, due to their adaptability to function with equipments from various manufacturers, being another integrated modular part of the E-Pumping project. Furthermore, in this thesis, through the study and performance tests of several statistical models based on time series, specifically applied to this problem, a forecasting tool adaptable to any station, and whose model parameters are automatically refreshed at runtime, was developed and added to the project as another module. Both the aforementioned modules were later integrated with an Graphical User Interface (GUI) and installed in a pilot application at the ADDP’s network. The implementation of this software on WSSs across the country will reduce the water supply companies’ running costs, improving their market competition and, ultimately, lowering the water price to the end costumer.
O rápido aumento dos preços da electricidade tem provocado um aumento na preocupação com a tarefa extremamente dispendiosa de transporte de água. Através da criação de modelos hidráulicos de redes de Sistemas de Fornecimento de Água, e da previsão do seu comportamento, é possível tirar vantagem das diferentes tarifas horárias de consumo de energia, reduzindo desta forma os custos totais do bombeamento de água. Esta tese foi desenvolvida em associação com o projecto de transferência de tecnologia denominado E-Pumping. Foca-se na procura de uma estratégia de supervisão e controlo flexível e adaptável a qualquer Sistema de Fornecimento de Água existente, bem como na previsão do consumo de água durante um período escolhido pelo utilizador final, o objectivo final é permitir o planeamento de um horário óptimo que minimize o custo do consumo de energia eléctrica. O Protocolo OPC, associado a uma Base de Dados MySQL, foi usado para o desenvolvimento da ferramenta de supervisão e controlo flexível, constituindo no seu conjunto um módulo do Projecto E-Pumping. A escolha baseou-se em ambas as tecnologias serem adaptáveis a equipamentos de diferentes fabricantes. Esta tese produziu ainda uma ferramenta de previsão do consumo de água, adaptável a qualquer estação, constituindo um segundo módulo do projecto. Esta ferramenta foi obtida através do estudo e testes de performance a variados modelos baseados em séries temporais, especificamente aplicadas a este problema. Os parâmetros do modelo de base desta ferramenta são automaticamente actualizados a cada execução do programa. Ambos os módulos referidos foram integrados com uma Interface Gráfica (GUI) e implementados numa aplicação piloto instalada na rede de abastecimento de água da empresa Águas do Douro e Paiva (ADDP). A implementação deste software em Sistemas de Abastecimento de Água por todo o país reduziria os seus custos de funcionamento, melhorando a sua capacidade de competição no mercado e, em última instância, diminuindo os preços da água para o consumidor final.
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Costa, Leonardo. "Control of water use in northwest Portugal." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/289751.
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Over the past 20 years, growing water demand in Spain has greatly reduced river flows into Portugal. Increasing pressures are expected on northern regions of Portugal, such as the Entre Douro e Minho (EDM), to reduce water use and improve quality. Two models, one theoretical and the other empirical, are developed to analyze water use by EDM agriculture. The theoretical model considers firms consuming and polluting water with multiple inputs, outputs, emissions, interdependent externalities, and transaction costs. The empirical model considers a flexible quadratic restricted profit model of representative farms for the region. A programming approach is followed. The Maximum Entropy technique is used to recover the profit model. An unrestricted profit function is obtained from the restricted profit function. The theoretical results show that when water externalities are interdependent it is not efficient to control each externality independently. Several policies exist to control interdependent externalities. All policies can be cost-effective, in theory. In practice, the policies have many transaction costs. The links between inputs, emissions, and ambient effects often are unknown. The focus then is on reducing farm use of inputs causing externalities. The empirical results show an inelastic response to prices. Nitrogen and water are complements. Coordination is required to reduce the use of each input. The decline of the Common Agricultural Policy (CAP) supports reduces pressure on water resources. At prices expected in 2000, the subsidies required to maintain farm profits range from three million contos (20% nitrogen reduction) to twelve million contos (20% nitrogen reduction plus 30% water reduction). However, total predicted expenditure for the subsidy program is only 3.3 million contos, which is clearly insufficient. The marginal value of water is only 5.6 esc/m3. Receiving 50 esc/m3, EDM agriculture will release 450 hm3 of water, 60% of its use.
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Schroeder, Robin L. "Exchange flows in an urban water body: Bayou St. John responses to the removal of flood control structures, future water elevation control, and water quality." ScholarWorks@UNO, 2011. http://scholarworks.uno.edu/td/1394.
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Bayou St. John, an urban water body extending south from Lake Pontchartrain, has two anthropogenic structures that regulate flow from the Lake . The City of New Orleans has plans to remove the inner control structure to improve water quality. Field and numerical methods used in this study show removing this structure increased water elevations throughout the Bayou but resulted in lower water elevation signal amplitudes that caused a lower tidal flow exchange from north to south. Bulk Richardson numbers showed mixing was inversely related to flow and the Bayou generally remains stratified. Resuspension of contaminated sediment could negatively impact the local ecology but predicted shear stress values did not reach a critical value (0.1 N/m2) for resuspension. Removal of the waterfall structure will benefit Bayou St. John by decreasing energy losses from the Lake, however a more pronounced tidal signal from Lake Pontchartrain is required to flush the Bayou.
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Salam, Md Abdul, and Md Mafizul Islam. "Modelling and Control System Design to control Water temperature in Heat Pump." Thesis, Karlstads universitet, Avdelningen för fysik och elektroteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-30680.
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The thesis has been conducted at Hetvägg AB and the aim is to develop a combined PID and Model Predictive Controller (MPC) controller for an air to water heat pump system that supplies domestic hot water (DHW) to the users. The current control system is PLC based but because of its big size and expensive maintenance it must be replaced with a robust controller for the heat pump. The main goal of this project has been to find a suitable improvement strategy. By constructing a model of the system, the control system has been evaluated. First a model of the system is derived using system identification techniques in Matlab-Simulink; since the system is nonlinear and dynamic a model of the system is needed before the controller is implemented. The data has been estimated and validated for the final selection of the model in system identification toolbox and then the controller is designed for the selected model. The combined PID and MPC controller utilizes the obtained model to predict the future behavior of the system and by changing the constraints an optimal control of the system is achieved. In this thesis work, first the PID and MPC controller are evaluated and their results are compared using transient and frequency response plots. It is seen that the MPC obtained better control action than the PID controller, after some tuning the MPC controller is capable of maintaining the outlet water temperature to the reference or set point value. Both the controllers are combined to remove the minor instabilities from the system and also to obtain a better output. From the transient response behavior it is seen that the combined MPC and PID controller delivered good output response with minimal overshoot, rise time and settling time.
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Spiller, Marc. "EU water policy : pollution source control by water companies in England and Wales." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/4586.
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Water management is undergoing a transformation towards integration, source control and ecological thinking. In the EU, the Water Framework Directive can be considered as a driver towards this new approach to water management. Innovations are deemed necessary to deliver this ideal of water management. In this thesis efforts by water sewerage companies in England & Wales to rectify agricultural pollution at source are viewed as an organisational innovation towards more sustainable water management. These source control interventions can help achieving the goals of the Water Framework Directive by reducing diffuse pollution from agriculture, fostering participation in water management and by reducing overall cost of implementation. This thesis contributes to understanding the process of change in water management by developing a model of the innovation-decision process. Insights about how innovation and therefore change can be influenced is generated by applying this model to the process of source control intervention adoption by water and sewerage companies. This research employed a flexible research design using comparative case studies. Each of the 10 water and sewerage companies in England and Wales represented an individual case. Data were collected in two phases using semi-structured interviews with selected water and sewerage company representatives. Thematic analysis, recurrence counts and content analysis were applied to analyse interviews. It was found that water companies are likely to contribute towards integrated approaches to water management, since there is a trend to adopt source control intervention. Change in water management is influenced by the interaction of factors from the domains: ‗Natural-Physical‘, ‗Organisational Characteristics‘, ‗Regulatory- Institutional‘ and ‗Innovation Attributes‘. The rate of change by water and sewerage companies is governed by a combination of asset characteristics, environmental state changes and the funding cycle. Furthermore, innovation is triggered by direct regulation and regulation that requires the gathering of information. Contrary to this flexible or framework regulation performs better in guiding the direction of change.
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Zhu, Tingju. "Climate change and water resources management : adaptations for flood control and water supply /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.
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Caraballo, Ginna. "An Arduino Based Control System for a Brackish Water Desalination Plant." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804931/.
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Water scarcity for agriculture is one of the most important challenges to improve food security worldwide. In this thesis we study the potential to develop a low-cost controller for a small scale brackish desalination plant that consists of proven water treatment technologies, reverse osmosis, cation exchange, and nanofiltration to treat groundwater into two final products: drinking water and irrigation water. The plant is powered by a combination of wind and solar power systems. The low-cost controller uses Arduino Mega, and Arduino DUE, which consist of ATmega2560 and Atmel SAM3X8E ARM Cortex-M3 CPU microcontrollers. These are widely used systems characterized for good performance and low cost. However, Arduino also requires drivers and interfaces to allow the control and monitoring of sensors and actuators. The thesis explains the process, as well as the hardware and software implemented.
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Owusu-Sekyere, Joshua Danso. "Water table control for rice production in Ghana." Thesis, Cranfield University, 2005. http://hdl.handle.net/1826/1076.
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An investigation has been undertaken to determine the consequence of using water table control for lowland rice production by growing rice varieties Azucena and IR36 in sand cores under a controlled environment in a series of experiments in which the water table was held at fixed levels. Each experiment had a duration of six weeks and in all, four treatments were used: (a) water table at a depth of 30 cm below the surface, (b) water table at a depth of 15 cm below the surface, (c) saturated sand and (c) flooded sand. Growth under the two water table depths compared favourably with the flooded and saturated conditions, with plants under the water table control treatments in some cases performing better in terms of plant performance than the saturated or flooded. Plant growth parameters measured were: Tiller number, root dry mass, shoot dry mass, rooting depth, total root length and plant height. Other parameters measured are: Solution nitrogen concentration, redox potential, growth medium temperature and pH levels.
When IR36 was used the total root length, number of roots and tiller numbers were significantly greater for the plants in the saturated treatment but there were no significant differences in root mass, shoot mass, and shoot length with regards to water depth. When Azucena variety was used, the 15 cm treatment had the highest shoot mass in addition to the highest tiller numbers. In other parameters, the 15 cm treatment did not show a significant difference to the saturated treatment. The 30 cm treatment performed least well in all parameters measured. Plants under the flooded treatment had a significantly greater root dry mass, shoot dry mass and tiller number than the others. The plants grown under 15 cm water table depth had the least root mass. Tiller numbers for the plants under the 30 cm water table depth were greater than those under the 15 cm water table depth. Differences in plant development parameters generally appeared only after the fourth week. The data suggest that irrespective of the water treatment used, plant development trends remain the same indicating that in the first four weeks of rice growth much less water can be used without affecting plant development.
Where Azucena and IR36 were both used the data suggest that water table control might be suitable for both varieties of rice. Differences in the amount of nitrogen present were seen to have had an impact on growth. Varying the form of nitrogen applied did not alter growth parameters to any appreciable extent implying that supply of nitrogen is more important than the form of nitrogen used.
The effect of root properties and NH4+ transport through the soil on N uptake under different water regimes has been modelled. The model adequately predicted the root length densities required to explain N uptake rates. It is shown that root length densities increase with decreasing moisture content, allowing larger root length densities to compensate for low nutrient transport rates and although diffusion of nutrients increased with increasing moisture levels, nutrient uptake rates did not follow the same pattern. Rooting length densities and transport of nutrients are not shown to limit uptake of nutrients under any of the water treatments imposed.
The feasibility of using water table control in the inland valleys of Ghana was also investigated by simulating the depth of the water table required in the dry season of the years 1996 and 1997. A comparison of water use under water table control and flooding irrigation showed that water savings were possible suggesting that water table control is feasible and beneficial in the inland valleys of Ghana.
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Germanopoulos, George. "Modelling and operational control of water supply networks." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/7746.
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Spanou, Maria N. "Object-oriented programming in river water quality control." Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/10119.
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In the present work object-oriented analysis and design have been applied for the quality management of river systems. The physical entities of the river system, as well as the conceptual entities for the flow and water quality analysis, the simulation and the pollution control strategies, have been represented through objects. By distributing appropriate responsibilities to these objects, daily low flows of the river gauge stations can be estimated for a duration of seven and thirty days and a recurrence interval of twenty years. Based on these flows optimum windows for the whole system and minimum daily flows of the river gauge stations can be also estimated. The minimum daily flows of each point of the river system can be provided. These are the design river flows for the management study. A simple statistical analysis of water quality in the river and the effluent of the plants can be also performed and the background concentrations of major constituents can be estimated. The simulation of water quality in the system can be also performed based on the design conditions of the study. Control strategies for the improvement of water quality can be finally applied and an optimized discharge scheme can be suggested. (Abstract shortened by UMI.)
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Shirif, Ezeddin. "Mobility control by polymer under bottom-water conditions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0002/NQ34831.pdf.
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Mowrey, James A. "Control system modeling for a boiling water reactor." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/17083.
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Yao, Huaming. "New control concepts for uncertain water resources systems." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/20239.
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Parent, Uribe Santiago. "Endotoxins detection and control in drinking water systems." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100231.
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Endotoxins are a constituent of the lipopolysaccharide (LPS) complexes present in the outer layer of the cell wall of most Gram-negative bacteria and some cyanobacteria. The ingestion by a typical adult of amounts exceeding 1,000 endotoxin units (EUs) can cause fever, diarrhoea, vomiting, acute respiratory illnesses, and lung inflammation. In contrast, much smaller doses may lead to protective immunity against allergic diseases.Endotoxins can be released in the air as well as in the water; previous studies have mainly focused on airborne endotoxins. Although many studies on endotoxins in raw and treated drinking waters have been performed, few have assessed seasonal variations and none have been conducted in Eastern Canada. Furthermore, a clear understanding of removal of endotoxins by various water treatment processes is still required.
Two methods to measure the concentrations of endotoxin were used and compared, the Limulus Amebocyte Lysate test (LAL) and the recombinant Factor C test (rFC). Raw water samples were taken from various drinking water sources around the Island of Montreal. The effects of free chlorine, UV radiation, and ozone were studied in batch experiments on filtered water samples via typical dosages and fluences used in drinking water treatment facilities. Residual concentrations for free chlorine were 0.8 and 1.6 mg/L; ozone doses were 0.5 and 1 mg/L; UV fluences were 40 and 100 mWs/cm2. Detention times of 20 and 60 minutes were tested for chlorine and 5 and 20 minutes for ozone. Grab sampling from three drinking water treatment plants in the Montreal area was performed during the months of June and late August/September 2006 and January 2007. Processes at these plants include coagulation and flocculation, sand filtration, ozonation and disinfection by chlorine. To test the variation in endotoxin concentrations during a sand filter cycle, samples were withdrawn directly from a filter in one of the treatment plants studied. The filtration cycle, from one backwash to the next one, lasts 72 h. Samples were collected immediately before the backwash, at the beginning and at the end of the ripening period, at the beginning of the filtration cycle and 48 h later, which corresponds to a half cycle period.
Of the two endotoxin detection methods used, LAL consistently gave slightly higher values compared to rFC; rFC also required more expensive hardware, but the method was less tedious and reagent costs were lower. Results presented, unless otherwise stated, were obtained with the rFC method. Endotoxin levels decreased in raw water samples between June and September. Concentrations ranged from 20 to 30 EU/mL in June, and decreased to 10 to 14 EU/mL in August and beyond. For the disinfection processes, the UV and free chlorine doses tested had little or no effect on the endotoxin concentrations, but ozone reduced the concentrations by up to 75%. Sand filtration and flocculation showed significant endotoxin removal efficiencies (50--60%). Levels remained around 5 EU/mL throughout the remaining treatment processes regardless of the influent concentration. Hence, endotoxin inactivation by free chlorine and UV does not occur with typical doses used in drinking water treatment plants; in contrast, flocculation and sand filtration, as well as ozonation, are much more effective.
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Holmes, Paul Robin. "The effectiveness of organizations for water pollution control." Thesis, Lancaster University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287125.
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Lin, Shan. "Control of water transport in structured starch films." Thesis, University of East Anglia, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492965.
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Khairou, Khalid Sulaiman. "Structure and control of water in copolymeric hydrogels." Thesis, University of Salford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305884.
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Yip, D. C. F. "Nature and control of water in synthetic hydrogels." Thesis, University of Salford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381735.
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Montero, Juan-Pablo. "Uncertainty and the markets for water pollution control." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/36315.
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Kilmer, John. "Telemetry in an Automated Water Supply Control System." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/611450.
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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, CaliforniaThe White Sands Missile Range (WSMR) Water Supply Control System (WSCS) controls and monitors the water wells, tanks and booster pumps located at the southern end of the missile range. Figure 1 is an overview of the WSMR water supply system. The WSCS provides water for approximately 90 square miles of the 3,700 square mile missile range. The WSCS was designed and installed in 1990 and in need of upgrading and repair. The system was evaluated and found to be only moderately functional. The WSCS consists of an IBM compatible personal computer (PC) based user interface, located at the WSMR Water Plant and Fire Dept. and industrial-type computers called Programmable Logic Controller (PLC) based stations at the Water Plant, water wells and tanks. The stations communicate over a 400 MHz radio half-duplex link. The serial message utilizes the Cyclic Redundancy Check (CRC) and Block Check Character (BBC) type of error checking. The Master station controls pumping by downloading pump settings to the slave stations. The slave stations upload data to the master such as tank level, pump status, energy usage, gallons of water pumped and various alarms. The system was analyzed and the design was found to be sound. The system did require improvements. These improvements include adding surge suppressors, software upgrades, absolute reading flow rate sensors, and providing adequate environmental cooling for the control system. Procedures for periodic maintenance and calibration of the sensors and schedules for radio equipment maintenance were also developed. Software modifications to reduce WSMR energy usage by reducing pumping during peak energy demand times are being integrated into the WSCS. The peak energy demand times are determined by historical energy usage data.
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Unami, Koichi. "Optimization and Control of Water Conveyance/Storage Systems." Kyoto University, 1998. http://hdl.handle.net/2433/78094.
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Lessard, Paul. "Operational water quality management : control of stormwater discharges." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47538.
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Pushkarskaya, Helen N. "NONPOINT SOURCE WATER POLLUTION CONTROL: INCENTIVES THEORY APPROACH." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1041607329.
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Vairavamoorthy, Kalanithy. "Water distribution networks : design and control for intermittent supply." Thesis, Imperial College London, 1994. http://hdl.handle.net/10044/1/7193.
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Smith, S. Andrew Enticknap. "Water first." Connect to full text, 2002. http://thesis.anu.edu.au/public/adt-ANU20050314.135921/index.html.
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Kosov, Sergey. "Intelligent pressure control and diagnosis of water distribution networks." Thesis, De Montfort University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391542.
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Taljaard, Francois George. "Analytical control valve selection for mine water reticulation systems / F.G. Taljaard." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9703.
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Some of the largest and deepest mines in the world are situated in South Africa. Underground temperatures and humidity can be controlled by means of complex chilled water reticulation system. A cascade pumping system is used to pump the used water from the underground levels back to the surface.
The dewatering process is energy intensive. Large volumes of water are used during the general mine drilling periods (06:00 to 12:00). During blasting periods (15:00 to 18:00) a minimum amount of personnel are underground, yet large volumes of water are still sent underground due to a lack of control. Reducing the water sent underground, will reduce the amount of water pumped back to the surface; resulting in significant energy savings.
Water flow and pressure can be managed by installing control valves at appropriate positions throughout the water reticulation system. Selecting a control valve is typically governed by constraints such as cavitation, water hammer, flashing, safety ratings and control range. A basic set of calculations can be used to determine whether a valve conforms to a specific scenario. However, scenarios calculated by engineers are not indicative of all applied system scenarios.
When control valves are installed, to optimise the operation of a system, it affects the system’s characteristics. Sampled system data will therefore no longer provide adequate readings to help with selecting the correct control valve. An analytical control valve selection method has been developed and implemented. The case study shows the results and practical implications of applying this method in the mining industry. Implementing the analytical valve selection method is shown to be viable, realising electrical energy cost savings for the mine by reducing power requirements from Eskom. Analytical control valve selection for mine water reticulation systemsThesis (MIng (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2013.
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Mulhearn, David Thomas. "Community collaboration and restriction of use for the control of invasive threats in multipurpose reservoirs." Restricted access (UM), 2007. http://libraries.maine.edu/gateway/oroauth.asp?file=orono/etheses/37803141.pdf.
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Sun, Congcong. "Multi-layer model predictive control of complex water systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/326739.
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This thesis is devoted to design a multi-layer MPC controller applied to the complex water network taking into account that the different layers with different time scales and control objectives have their own controller. A two-layer temporal hierarchy coordinating scheme has been applied to coordinate the MPC controllers for the supply and transportation layers. An integrated real-time simulation-optimization approach which contributes to consider the effect of more complex dynamics, better represented by the simulation model, has been developed for regional water networks. The use of the combined approach of optimization and simulation coordination between simulator and optimizer allows to test the proposed multi-layer MPC in a feedback scheme using a realistic simulator of the regional network.
The second part of this thesis is focused on the design of a control scheme which uses the combination of linear MPC with a constraint satisfaction problem (CSP) to optimize the non-linear operational control of DWNs. The network aggregation method (NAM) is used to simplify a complex water network into an equivalent conceptual one for the bidirectional network before the use of CSP. The proposed approach is simulated using Epanet to represent the real DWN. Non-linear MPC is used for validation using a generic operational tool for controlling water networks named PLIO. A two-layer scheduling scheme for pump stations in a water distribution network has also been designed in the second part of this thesis. The tuning parameters of such algorithm are the lower layer control sampling period and the number of parallel pumps in the pump station.Aquesta tesi està dedicada a dissenyar un controlador MPC multicapa que s'aplica a una complexa xarxa regional emprant com a principal idea el fet de què les diferents capes treballen amb diferents escales de temps i objectius de control s'aconseguiran amb el seu propi controlador. Un esquema jeràrquic de coordinació temporal de dues capes s'ha aplicat per a coordinar als controladors MPC per a les xarxes de captació i transport. Un enfocament integrat de simulació-optimizació que contribueix a asegurar que l'efecte de les dinàmiques complexes, millor representades pel model de simulació s'hagin tingut en compte, s'ha propostat per la gestió operacional temps real de les xarxes regionals. La segona part d'aquesta tesi es centra en el disseny d'un esquema de control que utilitza la combinació del control MPC lineal amb una problema de satisfacció de restriccions (CSP) per optimitzar el control operacional no-lineal de les xarxes d'aigua potable. El mètode d'agregació de xarxes (NAM) s'utilitza per simplificar una xarxa d'aigua complexa en una xarxa conceptual bidireccional equivalent abans d'utilitzar el CSP. L'enfocament proposat es simula utilitzant Epanet per representar el comportament hidràulic de la xarxa d'aigua potable. Finalment, el MPC no lineal s'utilitza per a la validació fent ús de l'eina PLIO per a la seva implementació. I també, un esquema de planificació de dues capes per a estacions de bombament en una aigua xarxa de distribució ha estat proposat en la segona part d'aquesta tesi. Els paràmetres d'ajust d'aquest algorisme són el período de mostreig de control de la capa inferior i el número de bombes en paral·lel en la estació de bombament.
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Massons, Gassol Gerard. "Biofouling control in reverse osmosis membranes for water treatment." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/461092.
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L’osmosi inversa (OI) és una de les tecnologies de purificació d'aigua més competitives. Els sistemes d'OI han evolucionat significativament en els últims anys per a proporcionar solucions reals i sostenibles als problemes relacionats amb l'aigua. Un dels principals obstacles que impedeix l'expansió en l'ús d'OI en la reutilització de l'aigua, és la pèrdua de rendiment que els elements d'OI experimenten a l'operar amb aigües contaminades. Aquest fenomen de embrutament continua sent un dels majors reptes a resoldre per elements de OI utilitzats en plantes industrials o de tractament d'aigües residuals.
A causa de la complexitat d'estudiar aquests problemes en sistemes d'escala industrial, és necessari desenvolupar protocols per reproduir els efectes en equips de laboratori. Els efectes de l’embrutament solen apareixer després de diversos mesos. No obstant, per poder realitzar la recerca en un temps realista, el procés ha ser accelerat de forma controlada i el més realista possible. S'ha estudiat l'efecte de diferents variables operacionals en el desenvolupament de l’embrutament biològic. També s'ha avaluat el paper dels paràmetres de construcció de mòduls d'OI, provant en paral·lel diferents membranes i espaciadors, per millorar el disseny d'elements resistents al embrutament.
Els resultats dels assaigs realitzats demostren clarament que diferents químiques de membrana poden proporcionar una reducció significativa en els nivells de embrutament. Tot i això, es va trobar que el principal contribuent al desenvolupament dels biofilms es el espaciador. El disseny de l'espaciador es va estudiar en detall per aconseguir un comportament equilibrat en mòduls d'OI que tracten aigües amb un risc d’embrutament biològic elevat. Es van probar espaciadors amb diferents espessors, separacions i angles. Alguns dissenys van mostrar avantatges en la perdua de pressió generada, així com en l'acumulació d’embrutament biològic i orgànic.La osmosis inversa (OI) es una de las tecnologías de purificación de agua más competitivas. Los sistemas de OI han evolucionado significativamente en los últimos años para proporcionar soluciones reales y sostenibles a los problemas relacionados con el agua. Uno de los principales obstáculos que impide la expansión del uso de OI en la reutilización del agua es la pérdida de rendimiento que los elementos de OI experimentan al operar con aguas contaminadas. Este fenómeno de ensuciamiento sigue siendo uno de los mayores desafíos para los elementos de OI utilizados en plantas industriales o de tratamiento de aguas residuales. Debido a la complejidad de estudiar estos problemas en sistemas de escala industrial, es necesario desarrollar protocolos para reproducir los efectos en equipos de laboratorio. Los efectos del ensuciamiento suelen ocurrir después de varios meses. Sin embargo, para poder realizar la investigación en un tiempo realista, el proceso necesita ser acelerado de manera controlada y lo más realista posible. Se ha estudiado el efecto de diferentes variables operacionales en el desarrollo del ensuciamiento biológico. También se ha evaluado el papel de los parámetros de construcción de módulos de OI, probando en paralelo diferentes membranas y espaciadores, para mejorar el diseño de elementos resistentes al ensuciamiento. Los resultados de los ensayos realizados mostraron claramente que diferentes químicas de membrana pueden proporcionar una reducción significativa en los niveles de bioensuciamiento. Sin embargo, se encontró que el principal contribuyente al desarrollo de biofilms fue el espaciador. El diseño del espaciador se estudió en detalle para lograr un comportamiento equilibrado en módulos de OI que tratan aguas propensas al ensuciamiento biológico. Se ensayaron espaciadores con diferentes espesores, espaciamiento y ángulo. Algunos diseños mostraron ventajas en la perdida presión generada, así como en la acumulación de ensuciamiento biológico y orgánico.
Reverses osmosis (RO) filtration is one of the most competitive water purification technologies. RO systems have evolved significantly in the last years to provide real and sustainable solutions to water-related problems. One of the main hurdles that hinders RO expansion in water reuse, is the loss of performance that RO elements suffer when dealing with contaminated waters. This phenomenon known as fouling, remains to be one of the biggest challenges for RO elements used in industrial or wastewater treatment plants. Due to the complexity to study these problems in large scale systems, protocols need to be developed in order to mimic full-scale plants operation on a bench scale. Fouling problems are usually occurring after several month of operations. However, for a realistic time-scale research, the process needs to be accelerated in a controlled way and as similar as possible to what would be occurring naturally. The effect of different operating variables on biofouling development was studied. The role of RO module construction was also evaluated, testing different membranes and feed spacers side-by-side, to guide the improvements on the design of fouling resistant elements. The results from the trials performed clearly showed that different membrane chemistries can provide significant reduction in the levels of biofouling detected after operation. However, it was found that the main contributor to biofilm development was feed spacer. Large differences in the amount of biofouling generated could be associated with feed spacer presence. Feed spacer design was then studied in detail to achieve a balanced performance in spiral wound RO modules treating waters prone to biofouling. Feed spacers with various thickness, spacing and angle were tested and some designs showed advantages in pressure drops, as well as on biologic and organic fouling accumulation.
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Porter, Charles. "Public water policies: the ultimate weapons of social control." Doctoral thesis, Universitat Jaume I, 2016. http://hdl.handle.net/10803/398834.
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Khalafalla, Mazin. "Aperiodic Control for Quadruple Water tank system over WSAN." Thesis, KTH, Reglerteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91752.
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Zhao, Wen. "The Control of Water Contaminants Assisted by Natural Materials." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/7114.
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Natural materials can be used to remove water contaminants by applying proper physical, chemical, and biological water treatment processes. This study involves using natural materials, as they are considered to be more environmentally benign and cost-effective than synthetic materials. This dissertation concentrates on monitoring five major water quality parameters—ammonia, fluoride, turbidity, pH, and fecal indicator bacteria (FIB) —in two major applications where clean water is needed. The focus is on meeting the water quality requirements for each contaminant. The overall objective of this study is to control the levels of ammonia in aquaculture wastewater, and adjust fluoride, turbidity, pH, and FIB in drinking water by using natural materials. To accomplish this objective, this dissertation study is divided into two parts. Part I is about ammonia removal in aquaculture wastewater. Zeolite was the representative natural material that was used in this study. The methodologies presented include ion exchange and chemical neutralization processes. Part II is about fluoride, turbidity, pH and fecal indicator bacteria control in drinking water. Pumice stone was used in this study. The methodologies utilized in this work include biofiltration and adsorption.
In Part I, the methods of ion exchange and chemical neutralization as a function of ammonia removal efficiency, toxicity, and daily cost were compared. All these methods were found to remove ammonia by a simple drop-off system. Chabazite, a natural zeolite, was the ion exchanger source. Similarly, we compared the effectiveness of commercialized neutralizers versus a novel neutralizer prepared for this work. The ion exchanger (chabazite) had the highest ammonia removal in freshwater, but no significant ammonia removal in seawater was observed after in-vivo trials. However, for commercial water neutralizers, the in-vivo trials showed that they are not able to control ammonia levels in either freshwater or seawater. The novel neutralizer was found to have higher ammonia removal efficiencies in both freshwater and seawater. In terms of toxicity, the AmmoSorb can be considered non-toxic. To safely use the novel neutralizer, it is recommended to control its daily dose at 1 g/L/day followed by a two-thirds volume of water change every day. A comprehensive cost analysis also showed that the novel neutralizer was the least expensive ammonia remover.
In Part II, drinking water was treated by a bench-scale biosand filter system that included different filtration technologies, biological disinfection, and adsorption. The filtration technologies analyzed in this work include Aluminum Oxide Coated Pumice (AOCP) and sand. The AOCP also works as adsorption media to remove fluoride in water. As results, the AOCP imbedded biosand filter (BSF) can efficiently control fluoride, turbidity, and pH level to meet the WHO standards. In addition, the exhausted BSF can be regenerated by recoating the pumice with additional layers of aluminum oxide. The fluoride, turbidity, pH, as well as fecal indicator bacteria levels controlled by the regenerated BSF also meet the WHO standard for about one-month operation.
The overall contribution of this research is providing new methods to treat water at an affordable cost and an easy operational procedure with potential health benefits to the specific applications that require ammonia, fluoride, turbidity, pH, and E. coli levels to be controlled.
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Ahmed, Sara. "Questioning participation : culture and power in water pollution control." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335064.
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Pazouki, Kayvan. "Inferential measurement and control of ballast water treatment system." Thesis, University of Newcastle Upon Tyne, 2012. http://hdl.handle.net/10443/1433.
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As a result of interaction with the surrounding environment, shipping has become one of the vectors of bio-invasion across the globe. Ballast water is one of the means of bio-invasion from shipping through which microorganisms break through natural barriers and establish in a new location. Shipboard treatment systems are predominately considered as mitigating measures for bio-invasion via a ballast water system. Currently shipboard performance monitoring of ballast water treatment systems, and thus assessment of discharge quality of ballast water as required by the Convention, depends on off-line laboratory assays with long delay analysis. Lack of online measurement sensors to assess the viability of microorganisms after treatment has made monitoring and thus control of ballast water treatment systems difficult. In this study, a methodology was developed, through a mathematical algorithm, to provide an inferential model-based measurement system in order to monitor and thus control non-observable ballast water systems. In the developed inferential measurement the primary output of the treatment system is inferred by using easy to measure secondary output variables and a model relating these two outputs. Data-driven modeling techniques, including Artificial Neural Networks (ANN), were used to develop an estimator for the small scale UV treatment system based on the data obtained from conducted experiments. The results from ANN showed more accuracy in term of Root Mean Squared Error (RMSE) and Linear Correlation Coefficient (LCC) when compared to the other techniques. The same methodology was implemented to a larger scale treatment system comprising micro-filter and UV reactor. A software-based inferential measurement for online monitoring of the treatment system was then developed. Following monitoring, inferential control of the treatment setup was also accomplished using direct inverse control strategy. A software-based “Decision Making Tool” consisted of two intelligent inverse models, which were used to control treatment flow rate and maintain the effective average UV dose. The results from this study showed that software-based estimation of treatment technologies can provide online measurement and control for ballast water system.
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葉子良 and Tsz-leung Yip. "Active water-wave control by a submerged pitching plate." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31237976.
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Knowland, Thomas J. W. "Changing the guard? : institutional change in water pollution control." Thesis, University of East Anglia, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283949.
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