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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.
171

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)
172

A recursive programming analysis of water conservation in Arizona agriculture : a study of the Phoenix active management area

Lierman, Wally Kent. January 1983 (has links)
Arizona agriculture faces many changes in the near future. One of the most imminent changes will come from the enactment of the 1980 Arizona Groundwater Management Act. The 1980 AGWMA is designed ultimately to curtail the use of groundwater in Arizona. Agriculture will be affected since this sector used approximately 87 percent of all water in the State in 1980. This study reports on the possible effects that a proposed pump tax and water duty policy would have on agriculture within the Phoenix Active Management Area. The PAMA is one of four such areas in the State that have been identified as needing groundwater use management. The results of this study indicate that the proposed water duty is more effective in curbing groundwater use than the proposed pump tax. Investment in more water application efficient irrigation technologies is also important in this study. However, substantial amounts of capital investment funds will be needed to begin this investment.
173

Optimal well field design for reducing phreatophyte uptake losses

Nelson, Gregory A. January 1989 (has links)
A two-dimensional, finite difference model was used to simulate the lowering of the water table below a floodplain in order to affect water conservation by reducing phreatophyte transpiration. Evapotranspiration capture percentages and unit water costs associated with alternative well network designs were calculated in order to determine those factors which are most important in designing an evapotranspiration capture project.
174

Understanding Collaboration Among Political Subdivisions of State Government: Examining the Perceptions and Use of Collaboration by Virginia's Soil & Water Conservation Districts

Tyree, Kendall 02 April 2014 (has links)
The purpose of this study was to explore the definitions, benefits, challenges, methods and perceived levels of current collaboration of Virginia’s 47 Soil and Water Conservation Districts, each a political subdivision of state government. The study was guided by the following questions (1) What is collaboration and how is it used by political subdivisions of state government? (2) What collaborative strategies are used specifically by soil and water conservation districts? (3) At what level are districts currently collaborating? (4) At what level do districts prefer to collaborate? A mixed methods research survey was used. The quantitative section measured current perceptions of collaboration based on six indicators of successful collaborations as determined and tested by the Amherst Wilder Foundation—environment, membership, process and structure, communication, purpose, and resources—through use of its Collaborative Factors Inventory. The qualitative portion allowed further exploration into how districts are utilizing collaboration at a grassroots level. Desired levels of collaboration were also captured. The entire district population—district directors, associate directors, and staff—was surveyed and responses analyzed to better understand collaborative efforts. The results indicate that collaborations occur because of both the resource benefits received and the support of a greater cause—or a mix of relational exchange and resource dependency theories. Of the six collaborative indicators, resources proved the greatest area of concern. The process and structure variable was found to be a second needed area of growth. Trust issues with key partners, a component of the membership variable, were also identified as hindering collaboration. Overall, current perceived levels of collaboration occur between coordination and coalition, or a three to four on a five point scale. However, districts identified a desire to operate more often at the coalition level. By focusing on improvement to process and structure needs as well as resource issues, trust will improve and desired levels of collaboration can be reached. This study will enrich the existing literature by expanding on the use of collaboration as it relates to political subdivisions. Findings will be of value to all conservation districts, with greatest value to Virginia. Partner agencies, policymakers, and public administrators will further benefit by gaining insights into the collaborative process.
175

Metodologia para a implantação de programa de uso racional da água em edifícios. / Methodology for deployment of rational water use program in buildings.

Oliveira, Lúcia Helena de 08 October 1999 (has links)
Ações que influenciam a redução do consumo de água em edifícios têm sido implementadas, de forma generalizada, principalmente nos grandes centros urbanos, onde a escassez de água é uma realidade, quer seja por causas naturais, pelo aumento da demanda provocado pelo crescimento populacional ou por ambas as causas. Com o objetivo de sistematizar um Programa de Uso Racional da Água - PURA, para ser implantado em edifícios, foi desenvolvida uma metodologia cuja premissa básica é o conhecimento das características físicas e funcionais do sistema para o planejamento de ações mais eficientes de redução do consumo de água a serem implementadas e avaliadas. Assim, a metodologia foi estruturada em quatro etapas principais:auditoria do consumo de água, diagnóstico, plano de intervenção e avaliação do impacto de redução e, ainda com a recomendação de controle permanente do consumo de água como condição de estabilizar as reduções alcançadas. Ressalta-se que o planode intervenção enfatiza as ações tecnológicas e, dentre elas, a detecção e correção de vazamentos e substituição de sistemas e componentes convencionais por economizadores de água. Finalmente, a metodologia foi aplicada a duas tipologias de edifício - um hospital e uma escola. Os resultados obtidos foram bastante satisfatórios e mostraram que os níveis de consumo de água atuais podem ser diminuídos mantendo o desempenho do sistema e o grau de satisfação dos usuários, reduzindo os valores das contas de água e, além disso, contribuindo para a conservação dos recursos hídricos. / Actions that influence the reduction of water consumption within buildings have been implemented, a general way, mainly in big urban centers, where the scarcity of water is a reality due to nature reasons, increasing of water demand or both causes. With the objective to organize a Water Conservation Program to be implanted in buildings, a methodology was developed. Its basic premise is the knowledge of physical and functional characteristics of the system in order to plan more efficient actions towards the water consumption reduction that will be implemented and evaluated. Thus, the methodology was structured in four stages: water consumption audit, diagnosis, interventioning plan and impact reduction evaluation and with the recommendation of the necessity to control the water consumption as a condition to conserve the reductions gotten. It is important to stress the technological actions, such as leak detection and correction and the replacement of conventional components for saver ones. Finally, the methodology was applied in two typologies of building - first one in a hospital and second one in a school. The results were really satisfactory. They show that the present water consumption levels can be decreased maintaining the system performance and the satisfaction of the users, the reducing of the water bills and moreover contributing to the fresh water resources conservation.T
176

Beyond Water Restrictions: Informing Effective Lawn Watering Behavior

Unknown Date (has links)
Evaluating trends of historical rainfall on a weekly and seasonal basis is needed for optimizing the design and implementation of lawn water conservation strategies like outdoor water restrictions. While “day of the week” water restrictions are a typical strategy to limit the frequency and duration of urban lawn water use, they may not necessarily result in more conservative behaviors from end-users. Because weekly rainfall and local climate variables are seldom taken into account in water restriction strategies, they are not connected to actual lawn water demand. However, since lawn water demand is directly related to weekly rainfall totals, not to a particular number of watering days per week, water restriction schedules have the potential to unintentionally promote overwatering. This study investigated the weekly patterns of average seasonal rainfall and evapotranspiration in South Florida to determine the typical variability of weekly net irrigation needs and found that typical wet season weekly rainfall often provides a significant amount of water to meet the demand of residential lawns and landscapes. This finding underscores opportunity to reduce supplemental overwatering in residential landscapes if watering guidelines were modified to recognize seasonal average weekly rainfall in this region This study also tested a rainfall-based water conservation strategy to determine if providing residents with information about how local rainfall could promote more effective lawn watering behavior than just water restrictions alone. Experimental households reduced lawn water use by up to 61% compared to the control group by the end of the study. These results demonstrate that the neighborhood “rain-watered lawn” signs helped experimental study group households become more aware of rainfall as the primary input of water to their lawns. This study also investigated the role that lawn irrigation from self-supplied sources plays in the urban lawn water demand and investigates how the lawn water use and lawn watering behaviors of households that source from self-supply differ from those who source from the public supply. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
177

Programas permanentes de uso racional da água em campi universitários: o Programa de Uso Racional da Água da Universidade de São Paulo. / Permanent water conservation programs in university campi: the Water Conservation Program of the University of São Paulo.

Silva, Gisele Sanches da 09 March 2005 (has links)
No contexto da crescente problemática da água, soluções em diferentes níveis têm sido adotadas no Brasil e no mundo. Exemplo de atuação no nível dos sistemas prediais, o uso racional da água tem sido objeto de diversos estudos. Neste trabalho, são avaliados, segundo uma abordagem sistêmica, as atividades a serem contempladas na implementação de Programas Permanentes de Uso Racional da Água, especialmente em campi universitários, e seus potenciais resultados. Características dos campi como área, número de edificações, população e consumo de água elevados, além do desenvolvimento de múltiplas atividades, demonstram sua importância e justificam a atenção. São avaliadas, portanto, as atividades de planejamento, pré-implantação, implantação e pós-implantação, além das atividades de gestão da demanda de água, que devem permear todo o Programa. Como resultado desta implementação estruturada, propõe-se, como impactos - a redução do consumo de água, e como efeitos - alterações no sistema de suprimento de água fria, em rotinas administrativas e de manutenção predial, e em parâmetros de projeto; desenvolvimento tecnológico dos equipamentos; despertar para a conservação da água; e mudanças comportamentais dos usuários. A implementação e os resultados do Programa de Uso Racional da Água da Universidade de São Paulo (PURA-USP) completam o trabalho. Em desenvolvimento desde 1998, o PURA-USP obteve, como impactos até 2003, uma redução no consumo de água de 36% (de 137.881 para 88.366 m³/mês) e um benefício líquido acumulado de R$ 46,61 milhões. / In the context of the increasing water issues concerns, solutions at different levels have been adopted in Brazil and worldwide. As an example of actuation at the building systems level, water conservation has been the object of several studies. In this work, the activities to be fulfilled in the implementation of a Permanent Water Conservation Program, specially when applied to university campi, as well as the possible results are evaluated under a system approach. Campi characteristics such as area, number of buildings, population, and high water consumption, besides the development of multiple activities, show the importance of this issue and justify the concerns. The Program planning, pre-implantation, implantation and post-implantation activities, besides the water demand management activities - that must be carried out throughout the program - are evaluated then. As results of this structured implementation, it is proposed as impacts - the water consumption reduction, and as effects - the changes in the water supply systems, in administrative and building maintenance routines, in design parameters, in the technological development of fixtures, in the awakening for the alternatives water sources, and in the users behavior. The implementation and the results of the Water Conservation Program of the University of São Paulo (Programa de Uso Racional da Água da Universidade de São Paulo - PURA-USP) finish the work. The PURA-USP, in development since 1998, achieved as impacts, until 2003, 36% of water consumption reduction (from 137,881 to 88,366 m³/month) and gathered net benefit of US$ 16.13 millions (R$ 46,61 milhões).
178

A medição setorizada como instrumento de gestão da demanda de água em sistemas prediais - estudo de caso: Programa de Uso Racional da Água da Universidade de São Paulo. / Submetering as an instrument of water demand management in building systems – case study: Water Conservation Program of the University of São Paulo.

Tamaki, Humberto Oyamada 03 April 2003 (has links)
No presente trabalho é estudada a utilização da medição setorizada como instrumento de gestão da demanda de água em sistemas prediais. Para tanto, a caracterização dos medidores e a análise das interações dos elementos de medição com o sistema de suprimento de água fria e de equipamento sanitário são realizados a partir de um enfoque sistêmico e de desempenho. Considerando a coleta de melhores informações, qualitativamente e quantitativamente acerca do consumo, essencial para a gestão da demanda de água, e especialmente em um contexto de ações de conservação, neste trabalho levantou-se os sistemas de telemedição. Apresentou-se uma proposta de planejamento de implantação da medição setorizada e quais elementos que devem ser observados para a gestão da demanda. Para subsidiar as avaliações, realizou-se o estudo de caso da medição setorizada na Universidade de São Paulo, no qual foi possível verificar a importância da sua aplicação e os resultados extremamente positivos que justificaram sua implantação. / In this work it is studied the use of submetering as an instrument of water demand management in building systems. In such way, the characterization of the meters and the analysis of the interactions of its elements with the building hydraulical system are carried on a systemic approach and performance analysis of the proposal. Considering the collection of better information of water consumption essential for the water demand management, especially in a conservation context, it was searched out the systems and the technologies of remote metering. A proposal for the planning of the submetering implantation was showed, as well as the elements that should be considered for the demand management. To make the evaluations, the case study of the submetering program in the University of São Paulo was accomplished, in which it was possible to verify the importance of its application and the extremely positive results that had justified its implantation.
179

Perspectivas para conservação e reúso de água na indústria de alimentos - estudo de uma unidade de processamento de frangos. / Perspectives for water conservation and reuse in food industry - case study of a poultry processing plant.

Matsumura, Erika Myho 10 April 2007 (has links)
Na presente pesquisa foi abordado o conceito de conservação e reúso de água na indústria alimentícia, buscando mostrar a potencialidade de redução do consumo desse recurso. Foram avaliadas questões relacionadas à disponibilidade hídrica nos mananciais superficiais e subterrâneos quanto à sua quantidade e qualidade adequadas para consumo, além da questão legal da cobrança pelo uso da água. Essas provavelmente passarão a ser relevantes num futuro próximo, pressionando as indústrias a buscar meios para minimizar o consumo e gerar menos efluente. O objeto de estudo foi uma indústria de abate de frangos e por tratar-se de setor alimentício, com relação ao reúso de água, a avaliação limitou-se aos usos não potáveis. Embora a prática de reúso de água potável seja permitida em alguns países e existam regulamentações internacionais a respeito, no Brasil o tema ainda é recente sendo que até o momento há somente uma legislação dando diretrizes ao reúso não potável. Inicialmente foi avaliado o uso racional da água, identificando falhas operacionais, propondo melhorias e identificando perdas físicas. Na seqüência foram identificados os setores e os locais com maior consumo de água e geração de efluentes para depois estudar a adoção de técnicas de reúso de água. Dessa metodologia, foi possível obter uma redução global no consumo de água de 14,20% e um aumento na produção de 17,46%. Para aumentar a produção, foi avaliada a adoção de novas fontes de abastecimento. Pelos resultados obtidos, pode-se concluir que o programa de conservação e reúso de água é importante para a economia da indústria e seu desenvolvimento sustentável, e ao meio ambiente por preservar o recurso hídrico. / In this paper the application of water conservation and water reuse concepts in a food industry was studied, focusing the production improvement. It was analyzed issues related to water availability in surface and ground sources with respect to its quantity and quality for potable consumption, in addition to legal issues about charge of water use and effluent discharge, which will probably become very important in the near future, pushing industries for finding ways on how to minimize its water consumption and to generate less wastewater. The study was developed at a poultry processing plant, and because of it is a food industry, water reuse evaluation was limited for non potable applications. Although potable water reuse is allowed in some countries and there are international regulations about this practice, in Brazil this issue is recent, and up to now there is only a very general regulation that deals with non potable water reuse. At first it was evaluated rational water use strategies identifying operational fails, proposing improves and identifying physical losses. It was identified some sectors with high water consumption and wastewater generation, and so that, it also was evaluated practices of water reuse. Results showed a potential for 14.20% in water consumption reduction and a production increase of 17.46%. For more production increase, it was evaluated new water sources. With the results obtained it may be concluded that water conservation and water reuse programs are important for industry economy and its sustainability and for environment by preserving freshwater resources.
180

Estudo da viabilidade do aproveitamento de água de chuva para consumo não potável em edificações. / Rainwater catchment feasibility study for non-potable consumption in buildings.

May, Simone 13 May 2004 (has links)
Para a conservação de água existem medidas convencionais e medidas não convencionais. O sistema de aproveitamento de água da chuva para consumo não potável é uma medida não convencional. Atualmente o aproveitamento de água da chuva é praticado em países como Estados Unidos, Alemanha, Japão, entre outros. No Brasil, o sistema é utilizado em algumas cidades do Nordeste como fonte de suprimento de água. A viabilidade do uso de água da chuva é caracterizada pela diminuição na demanda de água fornecida pelas companhias de saneamento, tendo como conseqüência a diminuição dos custos com água potável e a redução do risco de enchentes em caso de chuvas fortes. No processo de coleta de água da chuva, são utilizadas áreas impermeáveis, normalmente o telhado. A primeira água que cai no telhado, lavando-o, apresenta um grau de contaminação bastante elevado e, por isso, é aconselhável o desprezo desta primeira água. A água de chuva coletada através de calhas, condutores verticais e horizontais é armazenada em reservatório podendo ser de diferentes materiais. A água armazenada deverá ser utilizada somente para consumo não potável, como em bacias sanitárias, em torneiras de jardim, para lavagem de veículos e para lavagem de roupas. Este trabalho trata da avaliação da qualidade da água da chuva, juntamente com o estudo da viabilidade econômica da utilização de um sistema de coleta e aproveitamento da água da chuva. A partir de um sistema experimental, análises da composição física, química e bacteriológica da água da chuva foram realizadas para caracterizar a água e verificar a necessidade de tratamento, diminuindo riscos à saúde de seus usuários. A viabilidade do sistema depende basicamente de três fatores: precipitação, área de coleta e demanda. O reservatório de água da chuva, por ser o componente mais dispendioso do sistema, deve ser projetado de acordo com as necessidades do usuário ecom a disponibilidade pluviométrica local para dimensioná-lo corretamente, sem inviabilizar economicamente o sistema. Baseado nos resultados das análises realizadas e na utilização do sistema de coleta e aproveitamento de água da chuva, seu uso para fins não potáveis deve ser estimulado. / There are conventional and non-conventional ways for water conservation. The rainwater catchment system for non-drinking use is a non-conventional way. Nowadays, the exploitation of the rainwater is found in the United States, Germany, Australia and Japan, among others. In Brazil, the system is used in some northeast cities as water supplement supply source. The feasibility of rainwater use is characterized by the reduction of the demand on water supplied by the sanitation company and, as a consequence, the reduction of costs and the reduction of flood risk in case of storm rain. In the process of rainwater catchment impermeable areas are used, in most of cases, the roof. The first water that falls and washes the roof has sufficiently high degree of contamination and therefore it is a advisable to discharge it. The rainwater caught by gutters, vertical and horizontal conductors, is stored in a rainwater reservoir, which can be made of different materials. The stored rainwater should be used only for non-drinking consumption like in the toilet, in garden taps, in car washing and in clothes laundering. This paper evaluates the rainwater quality and develops the feasibility study for rainwater catchment for non-drinking use. From an experimental system, physical, chemical and microbiological analyses of the rainwater were made to qualify and verify the need of treatment avoiding the risk of illness to users. The feasibility of the system depends firstly on three factors: precipitation, catchment area and demand. The rainwater reservoir, as the most expensive part of the system, should be designed accordingly to the consumption and the local precipitation availability to set it accordingly, without making it economically unfeasible. Based on the results of the analysis and on the rainwater catchment system, its application for non-drinking use should be stimulated.

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