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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Modelagem estocástica da demanda individualizada de água residencial / Stochastic modelling of individualized residential water demand

Rafael Gaspar Damiano 01 October 2018 (has links)
A modelagem da demanda de água residencial fornece importantes subsídios ao dimensionamento e gerenciamento de redes de abastecimento de água. O comportamento desta demanda pode ser descrito através de processos estocásticos, caracterizados pela ocorrência de pulsos retangulares de demanda de água ao longo do tempo. Nesse contexto, este trabalho de pesquisa teve como objetivos monitorar e modelar a demanda de água residencial através dos modelos estocásticos dos pulsos retangulares de Neyman Scott (NSRP) e dos Pulsos Totais (OP). Enquanto que no modelo NSRP há a tentativa de simular a demanda de água através da representação dos seus constituintes elementares, no modelo OP busca-se a representação direta da demanda de água agregada dos usuários finais, como observada nos hidrômetros. A calibração e a validação dos modelos foram feitas a partir do monitoramento do consumo de água de quatro residências localizadas na cidade de São Carlos, caracterizadas por perfis de abastecimento distintos. Para tanto, foram desenvolvidos dispositivos dataloggers, que associados aos sensores/emissores de pulsos dos hidrômetros, permitiram o monitoramento do consumo de água ao longo do tempo dos usuários residenciais individuais. Durante a elaboração da pesquisa, foram observados efeitos negativos nas modelagens relacionados à influência dos reservatórios domiciliares (caixas d\'água) no perfil temporal do consumo de água das residências. Buscando mitigar esses efeitos, foram propostas modificações nas etapas de calibração e de geração das séries sintéticas de demanda de água. De uma forma geral, observou-se que as modificações propostas contribuíram para que as séries sintéticas geradas a partir dos modelos NSRP e OP reproduzissem de forma mais acurada as estatísticas das séries observadas, principalmente com relação às intensidades e durações das demandas simuladas. Apesar de as versões modificadas dos modelos NSRP e OP apresentarem desempenho similar na reprodução das médias, variâncias e covariâncias das séries observadas, o modelo OP reproduziu de forma mais consistente os volumes consumidos diários observados. / The modelling of residential water demand provides important subsidies for the design and management of water supply networks. The behavior of this demand can be described through stochastic processes, characterized by the occurrence of rectangular pulses of water demand over time. In this context, the objectives of this research were to monitor and model residential water demand using the Neyman Scott Rectangular Pulse model (NSRP) and Overall Pulse model (OP). While in the NSRP model there is the attempt to simulate the water demand through the representation of its elementary constituents, the OP model aims to direct represent the aggregate water demand of the end users, as observed in water meters. The calibration and validation of the models were done by monitoring the water consumption of four residences located in the city of São Carlos, characterized by different supply profiles. To this end, dataloggers were developed, which, coupled with sensors/pulse emitters and water meters, allowed the monitoring of water consumption over time of individual residential users. During the research, negative effects were observed in the models, related to the influence of the domestic reservoirs on the temporal patter of water consumption of the residences. To mitigate these effects, modifications were proposed in the calibration and generation stages of the synthetic water demand generation series. In general, it was observed that these proposed modifications contributed to a more accurately reproduction of the observed series statistics by the OP and NSRP synthetic series, especially regarding the intensities and durations of the simulated demands. Although the modified versions of the NSRP and OP models presented similar performance in the reproduction of the means, variances and covariance of the observed series, the OP model reproduced in a more consistent way the observed daily consumed volumes.
132

Modelagem estocástica da demanda individualizada de água residencial / Stochastic modelling of individualized residential water demand

Damiano, Rafael Gaspar 01 October 2018 (has links)
A modelagem da demanda de água residencial fornece importantes subsídios ao dimensionamento e gerenciamento de redes de abastecimento de água. O comportamento desta demanda pode ser descrito através de processos estocásticos, caracterizados pela ocorrência de pulsos retangulares de demanda de água ao longo do tempo. Nesse contexto, este trabalho de pesquisa teve como objetivos monitorar e modelar a demanda de água residencial através dos modelos estocásticos dos pulsos retangulares de Neyman Scott (NSRP) e dos Pulsos Totais (OP). Enquanto que no modelo NSRP há a tentativa de simular a demanda de água através da representação dos seus constituintes elementares, no modelo OP busca-se a representação direta da demanda de água agregada dos usuários finais, como observada nos hidrômetros. A calibração e a validação dos modelos foram feitas a partir do monitoramento do consumo de água de quatro residências localizadas na cidade de São Carlos, caracterizadas por perfis de abastecimento distintos. Para tanto, foram desenvolvidos dispositivos dataloggers, que associados aos sensores/emissores de pulsos dos hidrômetros, permitiram o monitoramento do consumo de água ao longo do tempo dos usuários residenciais individuais. Durante a elaboração da pesquisa, foram observados efeitos negativos nas modelagens relacionados à influência dos reservatórios domiciliares (caixas d\'água) no perfil temporal do consumo de água das residências. Buscando mitigar esses efeitos, foram propostas modificações nas etapas de calibração e de geração das séries sintéticas de demanda de água. De uma forma geral, observou-se que as modificações propostas contribuíram para que as séries sintéticas geradas a partir dos modelos NSRP e OP reproduzissem de forma mais acurada as estatísticas das séries observadas, principalmente com relação às intensidades e durações das demandas simuladas. Apesar de as versões modificadas dos modelos NSRP e OP apresentarem desempenho similar na reprodução das médias, variâncias e covariâncias das séries observadas, o modelo OP reproduziu de forma mais consistente os volumes consumidos diários observados. / The modelling of residential water demand provides important subsidies for the design and management of water supply networks. The behavior of this demand can be described through stochastic processes, characterized by the occurrence of rectangular pulses of water demand over time. In this context, the objectives of this research were to monitor and model residential water demand using the Neyman Scott Rectangular Pulse model (NSRP) and Overall Pulse model (OP). While in the NSRP model there is the attempt to simulate the water demand through the representation of its elementary constituents, the OP model aims to direct represent the aggregate water demand of the end users, as observed in water meters. The calibration and validation of the models were done by monitoring the water consumption of four residences located in the city of São Carlos, characterized by different supply profiles. To this end, dataloggers were developed, which, coupled with sensors/pulse emitters and water meters, allowed the monitoring of water consumption over time of individual residential users. During the research, negative effects were observed in the models, related to the influence of the domestic reservoirs on the temporal patter of water consumption of the residences. To mitigate these effects, modifications were proposed in the calibration and generation stages of the synthetic water demand generation series. In general, it was observed that these proposed modifications contributed to a more accurately reproduction of the observed series statistics by the OP and NSRP synthetic series, especially regarding the intensities and durations of the simulated demands. Although the modified versions of the NSRP and OP models presented similar performance in the reproduction of the means, variances and covariance of the observed series, the OP model reproduced in a more consistent way the observed daily consumed volumes.
133

Tucson's Tools for Demand Management

Davis, S. T. 15 April 1978 (has links)
From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / Tucson's "Beat the Peak" program implemented in the summer of 1977 effectuated a reduction in peak day water usage from 151.5 million gallons per day on July 9, 1976, to 114.0 million gallons per day on July 8, 1977. This twenty-five percent reduction, if maintained, will allow a three -year deferral of a new remote wellfield and transmission pipeline estimated to cost between $25 and $50 million. More time will be available to analyze the cost effectiveness of solutions to the region's water resources supply problems (such as imported groundwater, Central Arizona Project water, effluent reuse, and their interrelationships). Although conservation was not promoted, the successful peak management program resulted in a 13.3 percent reduction in 1977 water use during the summer months (May through August) compared to usage during the same period in 1976. This resulted in water sales revenues less than projected, but the combination of less utility expenses and deferred capital improvements will yield lower customer rates and monthly bills than would have otherwise been necessary without the program.
134

Wastewater Effluent - An Element of Total Water Resource Planning

Goff, J. D. 15 April 1978 (has links)
From the Proceedings of the 1978 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 14-15, 1978, Flagstaff, Arizona / Wastewater reuse options for the Phoenix area include: agricultural irrigation, fish and wildlife enhancement, ground water recharge, industrial processing and coiling water, recreation, cooling water for power generation stations, and exchanging effluent for additional water supplies. Consideration is given to effluent reuse potential as a commodity to exchange for water suitable for domestic water supply. This exchange would result in yet additional reuses of the water as title to the effluent could be assured by contracts and agreements.
135

Estimativa da demanda residencial urbana de ?gua: o caso da cidade de Te?filo Otoni

Figueiredo, S?lvio Luiz de 11 February 2017 (has links)
Submitted by Raniere Barreto (raniere.barros@ufvjm.edu.br) on 2018-05-07T18:19:12Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) s?lvio_luiz_figueiredo.pdf: 1948091 bytes, checksum: 9615d43a375d54bc9dbbf67d8bec0dfb (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-05-14T14:29:30Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) s?lvio_luiz_figueiredo.pdf: 1948091 bytes, checksum: 9615d43a375d54bc9dbbf67d8bec0dfb (MD5) / Made available in DSpace on 2018-05-14T14:29:30Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) s?lvio_luiz_figueiredo.pdf: 1948091 bytes, checksum: 9615d43a375d54bc9dbbf67d8bec0dfb (MD5) Previous issue date: 2017 / O trabalho tem como objetivo estimar a demanda de ?gua do sistema de abastecimento p?blico da Cidade de Te?filo Otoni ? MG, bem como examinar os efeitos das vari?veis determinantes em seu comportamento. Permite ainda uma compreens?o do cen?rio pesquisado, possibilitando, deste modo, analisar a magnitude de poss?veis pol?ticas tarif?rias utilizadas, sendo capaz de sustentar no processo decis?rio sobre a necessidade de investimentos, por meio de proje??es do consumo. Para esse fim, utilizou-se t?cnicas de an?lise explorat?ria temporal de dados, considerando o per?odo de setembro de 2012 a dezembro de 2014, dividida em duas categorias de consumo: social e normal. O modelo de demanda de ?gua apoiou-se na estrutura tarif?ria da Companhia de Saneamento de Minas Gerais (COPASA-MG), visando avaliar aspectos importantes tanto para o servi?o de abastecimento de ?gua quanto de consumidores. Ressalta-se a import?ncia das vari?veis pre?o m?dio, renda e clima, objetivando-se substancialmente em encontrar os par?metros de elasticidade. A compreens?o desses par?metros viabiliza uma an?lise do impacto de pol?ticas tarif?rias e possibilita a proje??o do consumo futuro de ?gua no longo prazo. Os resultados encontrados destacam a inelasticidade pre?o da demanda de ?gua para ambas categorias estudadas, apresentando coeficientes significativos para o pre?o marginal e a vari?vel diferen?a. A quantidade de ?gua defasada e a renda para ambas as categorias estudadas, n?o apresentaram o sinal esperado pela literatura; j? o clima, na categoria normal, o coeficiente n?o foi significativo estatisticamente; e na categoria social, o coeficiente mostrou-se significativo. Portanto, presume-se um maior conhecimento na estrutura tarif?ria da cidade, al?m da busca por vari?veis que expliquem melhor a demanda de ?gua. / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Tecnologia, Sa?de e Sociedade, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / The objective of this work is to estimate the water demand of the Te?filo Otoni - MG public water supply system, as well as to examine the effects of the determinant variables on its behavior. It also allows an understanding of the researched scenario, thus making it possible to analyze the magnitude of possible tariff policies used, being able to sustain in the decision making process on the need for investments, through consumption projections. For this purpose, we used techniques for exploratory temporal data analysis, considering the period from September 2012 to December 2014, divided into two categories of consumption: social residential and normal residential. The water demand model was based on the tariff structure of the Minas Gerais Sanitation Company (COPASA-MG), in order to evaluate important aspects for both the water supply service and consumers. The significance of the variables average price, income and climate is emphasized, aiming substantially at finding the parameters of elasticity. The understanding of these parameters enables an analysis of the impact of tariff policies and enables the projection of future water consumption in the long term. The results found highlight the price inelasticity of water demand for both categories studied, presenting significant coefficients for the marginal price and the difference variable. The coefficient was not statistically significant, in the social category, the coefficient showed to be highly significant. The coefficient was not statistically significant, in the social category, the coefficient showed to be highly significant. Therefore, it is assumed a greater knowledge in the tariff structure of the city, besides the search for variables that better explain the water demand.
136

A proactive water supply shortage response plan focusing on the Green Industry in the Rand Water supply area

Hoy, Leslie Higham 01 1900 (has links)
Water is a symbol of life. It affects all organisms on earth and its importance is emphasised in times of drought. The human population growth places more demands on our natural resources. As pressures on the available water increases, more measures are required to utilise water sustainably. South Africa is classified as a water stressed country with less than 1700 cubic meters of water available per person per year. Rand Water supplies water to approximately 11 million people in Gauteng. During times of drought, restrictions imposed are aimed mainly at the broader Green Industry. This research investigated international strategies, existing restrictions in Gauteng, and undertook a survey within the Green Industry to determine the most appropriate response. This research proposes a new water supply shortage response plan for Rand Water in Gauteng with a total of four levels of restrictions implemented at different stages of water stress in the system. / Environmental Sciences / M. Sc. (Environmental Management)
137

Gerenciamento de demanda de água em ambientes de uso público: o caso da Universidade Federal de Campina Grande. / Management of water demand in public buildings: the case of the Universidade Federal de Campina Grande.

SOARES, Antonio Leomar Ferreira. 27 September 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-09-27T15:24:05Z No. of bitstreams: 1 ANTONIO LEOMAR FERREIRA SOARES - DISSERTAÇÃO PPGECA 2012..pdf: 13208663 bytes, checksum: b3c6e6dddf91e5d0adb7fe7815cd422b (MD5) / Made available in DSpace on 2018-09-27T15:24:05Z (GMT). No. of bitstreams: 1 ANTONIO LEOMAR FERREIRA SOARES - DISSERTAÇÃO PPGECA 2012..pdf: 13208663 bytes, checksum: b3c6e6dddf91e5d0adb7fe7815cd422b (MD5) Previous issue date: 2012-02 / A água, um bem indispensável à vida, está se tornando a cada dia mais escasso, principalmente nas regiões semiáridas, como o Nordeste brasileiro, caracterizadas por secas sucessivas. Uma forma de solução sustentável é a gestão da demanda de água (GDA) - baseada no uso eficiente, garantindo a água no futuro, a partir do uso consciente no presente. Neste contexto, esta pesquisa partiu desses conceitos para estudar o caso da Universidade Federal de Campina Grande (UFCG), por ser um ambiente público, grande consumidor e sujeito a grandes desperdícios de água. Na análise foram diagnosticados o local e o sistema de abastecimento interno, o comportamento e percepção dos usuários para práticas de uso eficiente da água através de entrevistas e, por fim, simulações de medidas de GDA. Constatou-se através dos dados levantados que a demanda de água da UFCG apresentou crescimento absoluto de 118% de 2004 até 2010, ocasionado seja pelo crescimento da população, da área construída, dos vazamentos do sistema de abastecimento e maus hábitos dos usuários. Em relação aos usuários percebeu-se reprovação com seus hábitos de conservação de água, pois 75% afirmaram desperdiçar muita água na utilização dos aparelhos, sendo atribuída por eles próprios (76%) nota abaixo de 6,0 para suas condutas. Esta mesma avaliação sobre os usuários repercutiu na visão dos gestores da Instituição, que ainda consideraram importante a implantação de programas de redução de água devido às suspeitas de muita perda de água por vazamentos. Com as simulações verificaram-se índices de redução de consumo de água de até 50% com a substituição das bacias sanitárias pelo sistema bi-comando (3/6 litros) e um retorno do investimento em menos de 12 meses. Quando considerada a construção de cisternas para captação da água de chuva e aproveitamento no abastecimento das bacias sanitárias, verificou-se que para edificações com 8, 6 e 4 bacias sanitárias, a capacidade ótima do reservatório é de 20 m3, 25 m3 e 40 m3, com um índice de aproveitamento do sistema em 11%, 18% e 32%, respectivamente, demonstrando serem as medidas viáveis tanto ambientalmente quanto financeiramente. / Water, which is essential for sustaining life, is increasingly scarce, especially in semiarid regions such as northeastern Brazil, characterized by successive droughts. The management of water demand (MWD) is a sustainable solution - based on efficiency, ensuring water availability in the future, through the conscious use in the present. In this context, this research was based on these concepts in order to promote a reduction in water consumption. The case of the Universidade Federal de Campina Grande (UFCG) was studied, since it is a public setting, a large consumer of water and subjected to large water losses. In the analysis, the site and the supply system of UFCG were diagnosed, as well as the behavior and perception of users related to efficient water use, through interviews, and, finally, simulations of strategies of MWD were performed. It was found that the water demand at UFCG presented an absolute growth of 118% from 2004 to 2010, which was caused by growth of population, construction area, supply system leaks and bad habits of users. Regarding users, it was perceived disapproval of their own water conservation habits. This same assessment about users is shared by the managers of the institution, who considered to implement programs of water use reduction. The simulations showed reduced rates of water consumption up to 50% with the replacement of toilets at bicommand (3/6 liters) flush and a return of investment in less than 12 months. When considering construction of cisterns to capture rainwater and use in the supply of toilets, it was found that for buildings with 8, 6 and 4 toilets, the optimum capacity of the reservoirs are 20 m\ 25 m3 and 40 m3 with a utilization rate of the system in 11%, 18% and 32%, respectively, showing that the strategies are both environmentally and fmancially viable.
138

Water Demand and Allocation in the Mara River Basin, Kenya/Tanzania in the Face of Land Use Dynamics and Climate Variability

Dessu, Shimelis B 21 March 2013 (has links)
The Mara River Basin (MRB) is endowed with pristine biodiversity, socio-cultural heritage and natural resources. The purpose of my study is to develop and apply an integrated water resource allocation framework for the MRB based on the hydrological processes, water demand and economic factors. The basin was partitioned into twelve sub-basins and the rainfall runoff processes was modeled using the Soil and Water Assessment Tool (SWAT) after satisfactory Nash-Sutcliff efficiency of 0.68 for calibration and 0.43 for validation at Mara Mines station. The impact and uncertainty of climate change on the hydrology of the MRB was assessed using SWAT and three scenarios of statistically downscaled outputs from twenty Global Circulation Models. Results predicted the wet season getting more wet and the dry season getting drier, with a general increasing trend of annual rainfall through 2050. Three blocks of water demand (environmental, normal and flood) were estimated from consumptive water use by human, wildlife, livestock, tourism, irrigation and industry. Water demand projections suggest human consumption is expected to surpass irrigation as the highest water demand sector by 2030. Monthly volume of water was estimated in three blocks of current minimum reliability, reserve (>95%), normal (80–95%) and flood (40%) for more than 5 months in a year. The assessment of water price and marginal productivity showed that current water use hardly responds to a change in price or productivity of water. Finally, a water allocation model was developed and applied to investigate the optimum monthly allocation among sectors and sub-basins by maximizing the use value and hydrological reliability of water. Model results demonstrated that the status on reserve and normal volumes can be improved to ‘low’ or ‘moderate’ by updating the existing reliability to meet prevailing demand. Flow volumes and rates for four scenarios of reliability were presented. Results showed that the water allocation framework can be used as comprehensive tool in the management of MRB, and possibly be extended similar watersheds.
139

Studie snížení ztrát vody / The Study on Elimination of Water Losses

Klement, Jan January 2017 (has links)
The aim of this thesis is on selected locations to assess the actual condition of drinking water losses from water mains and propose option to reduce them.
140

Assessing the costs and benefits of water use for production and the potential of water demand management in the Crocodile Catchment of South Africa

Crafford, J.G. (Jacobus Gert) 23 July 2007 (has links)
In South Africa, precipitation is extremely variable and water is scarce. South Africa is also a country with great welfare needs. Challenging economic development targets and plans therefore need to be implemented successfully within the constraints of limited water supply and unreliable water availability. These economic development plans are underpinned by the development and growth of economic activities such as agriculture, mining, energy production and many types of small, medium and micro enterprises, which are some of the largest water using sectors in the economy. Within these activities, increased competition places pressure on water users to keep supplying their markets with competitively priced goods, while rising costs of new water supplies puts pressure on water users to allocate sufficient water to their production processes. These market forces and the relative scarcity of water as an economic production factor, impact on financial viability and imply that the economic efficiency of water use becomes increasingly important. The National Water Act of 1998 (NWA) is a legislative response to this situation, and promotes a radical shift towards efficiency and equity goals in water allocation. Water users who require water as an input to economic activities are consequently seriously revising their water use patterns in response to one of the major implications of the NWA and its related principal strategy: water demand management. Water demand management strives to adhere to the principles of equity, social justice, economic efficiency and environmental sustainability, which are central to the NWA. This study evaluates the costs and benefits of water use in order to simulate the effects of water demand management activities on a catchment economy. The results of a number of studies were combined to generate an economy-wide model: a Social Accounting Matrix (SAM), for the case study area and to simulate the direct and indirect effects of water demand management on the people, the economy and the natural environment in the area. Water demand management (WDM) is defined as consisting of two phases. In the first phase, goals of full cost recovery, improving water use efficiency and allocating water optimally are targeted. The second phase of WDM arrives when a situation of absolute water scarcity is reached within a catchment. In this phase water demand outweighs water supply and water has to be allocated according to its scarcity value. Water markets play a large role here. The SAM was used to simulate the direct and indirect impacts on the economy and the environment of a number of WDM related scenarios. Water e-allocation decisions and the effects of various WDM policy instruments, such as reduction of water use subsidies and increases in water tariffs were simulated. Unintended consequences of other environmental policies on water use, in this case, carbon tax, were explored. Water scarcity predictions were done, and some of the transaction costs involved in water trading was quantified. The study concludes with a discussion on the indirect effects on the economy, the environment and people of changes affecting the agricultural (including forestry) activities. The direct and indirect impacts of WDM policies on the economy and the environment, and the importance of environmental-economic models in water cost benefit modeling are also discussed. Implications for policy and management are highlighted. This study shows specifically how, through modelling various scenarios, policy decisions aimed at managing specific variables (e.g. water use, carbon emissions) have an economic and environmental impact much wider than the sector in which the policy was targeted for. Each scenario shows how a water transaction, or a change in subsidy in the agricultural (including forestry) sector, could impact on the output of other economic sectors, and therefore the economy as a whole. It is therefore evident that policy decisions, which are implemented at a macro level, and could have a major direct impact on a wider range of economic sectors, should be carefully considered as they could have large, undesirable, unintended consequences. / Dissertation (MSc (Agricultural Economics))--University of Pretoria, 2004. / Agricultural Economics, Extension and Rural Development / MSc (Agric) / unrestricted

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