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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.
1

A preliminary assessment of hydrogeologic suitability for Aquifer Storage and Recovery (ASR) in Oregon /

Woody, Jen. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 266-276). Also available on the World Wide Web.
2

Women, Water, and Perceptions of Risk : a case study made in Babati, Tanzania 2008

Hedman, Maria January 2009 (has links)
<p>More than 1 billion people in developing countries lack access to safe water and sanitation. Drinking water in these countries is often collected from unsafe sources outside the home. Even piped well water in the developing world can be unsafe due to inadequately maintained pipes, low pressure, intermittent delivery, lack of chlorination, and clandestine connections. Furthermore, drinking water often becomes contaminated after collection, either during transport or during storage in the home. Improvements in water supply, hygiene education and safe storage can reduce the spread of waterborne diseases, such as diarrhoea. However it is not an easy task to combat unsafe drinking water, and several factors have to be taken into account. Correct management of water at the household level is a vital factor in reducing contamination of water in areas where water is not available in the home, and often has to be transported for long distances before storage.</p><p>It is often a woman's responsibility to collect and store water. The aim of this study is to provide an understanding of women’s knowledge and perceptions of the risks associated with drinking water and waterborne diseases in Babati, Tanzania. Furthermore, the study sets out to investigate the methods utilized at the household-level to prevent waterborne diseases. Interviews were the key method to collecting primary data and the results present findings from 20 women in two villages in Babati. All of the respondents had access to community water pipes but none had taps in their household. Among the respondents who treated their water, the most common method of treatment was boiling. The study shows that there is a link between lived experience, perceptions of risk, and the way water is managed in the household.</p>
3

Microbial and physico-chemical assessment of on-site water supply systems /

Kolam, Joel. January 2003 (has links)
Thesis (M. Sc.) (Hons) -- University of Western Sydney, 2003. / "A thesis submitted in partial fulfilment of the requirements for the degree of Master of Science (Hons.), University of Western Sydney, Australia, Water Research Laboratory, Centre for Water & Environmental Technology." Includes bibliography : leaves 168 - 183 and appendices.
4

Women, Water, and Perceptions of Risk : a case study made in Babati, Tanzania 2008

Hedman, Maria January 2009 (has links)
More than 1 billion people in developing countries lack access to safe water and sanitation. Drinking water in these countries is often collected from unsafe sources outside the home. Even piped well water in the developing world can be unsafe due to inadequately maintained pipes, low pressure, intermittent delivery, lack of chlorination, and clandestine connections. Furthermore, drinking water often becomes contaminated after collection, either during transport or during storage in the home. Improvements in water supply, hygiene education and safe storage can reduce the spread of waterborne diseases, such as diarrhoea. However it is not an easy task to combat unsafe drinking water, and several factors have to be taken into account. Correct management of water at the household level is a vital factor in reducing contamination of water in areas where water is not available in the home, and often has to be transported for long distances before storage. It is often a woman's responsibility to collect and store water. The aim of this study is to provide an understanding of women’s knowledge and perceptions of the risks associated with drinking water and waterborne diseases in Babati, Tanzania. Furthermore, the study sets out to investigate the methods utilized at the household-level to prevent waterborne diseases. Interviews were the key method to collecting primary data and the results present findings from 20 women in two villages in Babati. All of the respondents had access to community water pipes but none had taps in their household. Among the respondents who treated their water, the most common method of treatment was boiling. The study shows that there is a link between lived experience, perceptions of risk, and the way water is managed in the household.
5

An Optimal Control Approach For Determiniation Of The Heat Loss Coefficient In An Ics Solar Domestic Water Heating System

Gil, Camilo 01 January 2010 (has links)
Water heating in a typical home in the U.S. accounts for a significant portion (between 14% and 25%) of the total home's annual energy consumption. The objective of considerably reducing the home's energy consumption from the utilities calls for the use of onsite renewable energy systems. Integral Collector Storage (ICS) solar domestic water heating systems are an alternative to help meet the hot water energy demands in a household. In order to evaluate the potential benefits and contributions from the ICS system, it is important that the parameter values included in the model used to estimate the system's performance are as accurate as possible. The overall heat loss coefficient (Uloss) in the model plays an important role in the performance prediction methodology of the ICS. This work presents a new and improved methodology to determine Uloss as a function of time in an ICS system using a systematic optimal control theoretic approach. This methodology is based on the derivation of a new nonlinear state space model of the system, and the formulation of a quadratic performance function whose minimization yields estimates of Uloss values that can be used in computer simulations to improve the performance prediction of the ICS system, depending on the desired time of the year and hot water draw profile. Simulation results show that predictions of the system's performance based on these estimates of Uloss are considerably more accurate than the predictions based on current existing methods for estimating Uloss.
6

Análise numérica de um sistema integrado coletor solar/armazenador térmico

Santos, Guilherme Henrique Sempionato Souza [UNESP] 10 August 2007 (has links) (PDF)
Made available in DSpace on 2016-04-01T17:54:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-10. Added 1 bitstream(s) on 2016-04-01T18:00:20Z : No. of bitstreams: 1 000505772.pdf: 2673100 bytes, checksum: 0b1ec10e248621594ebb61317344d2af (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este estudo apresenta uma análise numérica dos campos de temperaturas e velocidades d'água durante seu processo de aquecimento via calor sensível no interior de um armazenador térmico cilíndrico, aquecido lateralmente e adiabático em seu topo e base, visando o estudo da condição de operação de um aquecedor de água coletor solar-armazenador integrados (ICSSWH - Integrated Collector-Storage Water Heater). Em uma segunda análise a influência de um defletor interno é estudada pela definição dos campos de velocidades e temperaturas da água. A abordagem numérica é realizada a partir de um modelo bidimensional, transiente, não linear e em coordenadas cilíndricas, discretizada pela técnica de elementos finitos. A construção do modelo é obtida numericamente através de um código computacional desenvolvido em linguagem de programação C. Os resultados numéricos são validados. Análises transientes dos campos de velocidades e temperaturas bem como das temperaturas de mistura e velocidade de carregamento, com e sem parede interna direcionada (defletor interno) são realizadas com a finalidade de estudar a inlfuência da referida parede na convecção livre nessas condições. / This study shows a numerical analysis of the temperature and speed fields of water during the process of heating through sensible heat in the interior of a cylindric thermal storage, heated laterally and with adiabatics top and base, in order to study the operational conditions of an integrated collector-storage solar water heater (ICSSWH). In a second analysis a model with an internal baffle is created and temperature and velocity fields are analysed. The numerical study is done taking into consideration a bidimensional, transient non linear research in cylindric coordenates, discretized by the technique of finite elements. Its solution is obtained numerically through a computational code developed in a C programming language. The numerical results are validated. A transient analysis of the spped and temperature fields so as of the mixing temperatures and the charging speed, with or without the infernal baffle are carried out taking into account the aim of studying the influence of the so called wall in the free convection of those conditions.
7

Doses de N e K aplicadas via fertirrigação e espaçamento entre plantas influenciando o desenvolvimento, a produtividade e as relações hídricas em melancieira com e sem sementes

Gonsalves, Marcus Vinicius Irano [UNESP] 14 October 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-10-14Bitstream added on 2014-06-13T18:09:27Z : No. of bitstreams: 1 gonsalves_mvi_me_jabo.pdf: 689037 bytes, checksum: 058c47573833b69b7eb15e04313f24be (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A melancieira é cultivada praticamente em todo o território brasileiro, atingindo produção média anual no período de 1999/2006 de 1826134,5 t em área média anual de 81891,8 ha no mesmo período. A produção e qualidade dos frutos de melancia estão associadas a fatores genéticos, climáticos e fitotécnicos, sendo a nutrição da planta de fundamental importância para conseguir resultados satisfatórios. O nitrogênio e o potássio são os nutrientes extraídos em maior quantidade pela melancia e devem ser aplicados de forma e quantidade adequada e na época correta. Outro fator de grande importância no manejo cultural é o espaçamento, pois determina alterações morfofisiológicas na planta que repercutem no seu potencial produtivo e, também, no tamanho, formato e qualidade da hortaliça. Foram feitos dois experimentos, um com o híbrido Shadow (triplóide sem semente) e outro com o híbrido com semente Top Gun com o objetivo de avaliar os efeitos da aplicação via fertirrigação de doses de nitrogênio e potássio combinada com espaçamentos entre plantas na linha de plantio no desenvolvimento foliar e na produtividade da cultura para o híbrido sem sementes e para o híbrido com sementes. E também de avaliar o efeito dos espaçamentos no armazenamento de água no solo nos dois híbridos. Ambos os experimentos utilizaram o delineamento em blocos casualizados, em parcelas subdivididas, com quatro tratamentos principais e quatro tratamentos secundários, e três repetições. Os tratamentos principais corresponderam às doses de aplicação de N e K via fertirrigação (75%, 100%, 125% e 150% de 106,4 e 118 kg ha-1 de N e K, respectivamente). Os tratamentos secundários corresponderam aos espaçamentos entre plantas de 0,5, 1,0, 1,5 e 2,0 m, mantendo-se fixo o espaçamento de 2,0 m entre linhas de plantio. As mudas foram transplantadas em 05-08-2008, com uma folha não... / The watermelon is cultivated in virtually all of Brazil, reaching an average annual production over the period 1999/2006 of 1,826,134.5 tons in annual average area of 81,891.8 ha in the same period. The production and fruit quality of watermelon are associated with genetic factors, climatic elements and cultivar characteristics, and the plant nutrition is of fundamental importance for achieving satisfactory results. Nitrogen and potassium are the nutrients extracted in greater quantity by watermelon and should be applied in right quantity and at the correct time. Another factor of great importance in crop management is the spacing between plants, because it determines the plant morpho-physiological changes which result in their productive potential and also the size, shape and quality of vegetables. Two experiments were made, one with the Shadow Hybrid (triploid seedless) and the other with the hybrid with seed Top Gun with the objective of to evaluate the effects of doses of nitrogen and potassium applied by fertigation combined with spacing between plants on the line in leaf development and crop yield for hybrid seedless and the hybrid with seeds. And also to evaluate the effect of spacing on the water storage in the soil in the two hybrids. Both experiments used a randomized block design in split plots with four main treatments and four secondary treatments, and three replications. The main treatments corresponded to application of doses of N and K applied by fertigation (75%, 100%, 125% and 150% of 106.4 and 118 kg ha-1 of N and K, respectively). Secondary treatments corresponded to the spacing between plants of 0.5, 1.0, 1.5 and 2.0 m, keeping constant the spacing of 2.0 m between lines. The seedlings were transplanted on 05-08-2008, with a not-cotyledonary leaf fully grown. Were evaluated the leaf area index (LAI), leaf water potential, commercial and total productivity of ... (Complete abstract click electronic access below)
8

Doses de N e K aplicadas via fertirrigação e espaçamento entre plantas influenciando o desenvolvimento, a produtividade e as relações hídricas em melancieira com e sem sementes /

Gonsalves, Marcus Vinicius Irano. January 2009 (has links)
Resumo: A melancieira é cultivada praticamente em todo o território brasileiro, atingindo produção média anual no período de 1999/2006 de 1826134,5 t em área média anual de 81891,8 ha no mesmo período. A produção e qualidade dos frutos de melancia estão associadas a fatores genéticos, climáticos e fitotécnicos, sendo a nutrição da planta de fundamental importância para conseguir resultados satisfatórios. O nitrogênio e o potássio são os nutrientes extraídos em maior quantidade pela melancia e devem ser aplicados de forma e quantidade adequada e na época correta. Outro fator de grande importância no manejo cultural é o espaçamento, pois determina alterações morfofisiológicas na planta que repercutem no seu potencial produtivo e, também, no tamanho, formato e qualidade da hortaliça. Foram feitos dois experimentos, um com o híbrido Shadow (triplóide sem semente) e outro com o híbrido com semente Top Gun com o objetivo de avaliar os efeitos da aplicação via fertirrigação de doses de nitrogênio e potássio combinada com espaçamentos entre plantas na linha de plantio no desenvolvimento foliar e na produtividade da cultura para o híbrido sem sementes e para o híbrido com sementes. E também de avaliar o efeito dos espaçamentos no armazenamento de água no solo nos dois híbridos. Ambos os experimentos utilizaram o delineamento em blocos casualizados, em parcelas subdivididas, com quatro tratamentos principais e quatro tratamentos secundários, e três repetições. Os tratamentos principais corresponderam às doses de aplicação de N e K via fertirrigação (75%, 100%, 125% e 150% de 106,4 e 118 kg ha-1 de N e K, respectivamente). Os tratamentos secundários corresponderam aos espaçamentos entre plantas de 0,5, 1,0, 1,5 e 2,0 m, mantendo-se fixo o espaçamento de 2,0 m entre linhas de plantio. As mudas foram transplantadas em 05-08-2008, com uma folha não ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The watermelon is cultivated in virtually all of Brazil, reaching an average annual production over the period 1999/2006 of 1,826,134.5 tons in annual average area of 81,891.8 ha in the same period. The production and fruit quality of watermelon are associated with genetic factors, climatic elements and cultivar characteristics, and the plant nutrition is of fundamental importance for achieving satisfactory results. Nitrogen and potassium are the nutrients extracted in greater quantity by watermelon and should be applied in right quantity and at the correct time. Another factor of great importance in crop management is the spacing between plants, because it determines the plant morpho-physiological changes which result in their productive potential and also the size, shape and quality of vegetables. Two experiments were made, one with the Shadow Hybrid (triploid seedless) and the other with the hybrid with seed Top Gun with the objective of to evaluate the effects of doses of nitrogen and potassium applied by fertigation combined with spacing between plants on the line in leaf development and crop yield for hybrid seedless and the hybrid with seeds. And also to evaluate the effect of spacing on the water storage in the soil in the two hybrids. Both experiments used a randomized block design in split plots with four main treatments and four secondary treatments, and three replications. The main treatments corresponded to application of doses of N and K applied by fertigation (75%, 100%, 125% and 150% of 106.4 and 118 kg ha-1 of N and K, respectively). Secondary treatments corresponded to the spacing between plants of 0.5, 1.0, 1.5 and 2.0 m, keeping constant the spacing of 2.0 m between lines. The seedlings were transplanted on 05-08-2008, with a not-cotyledonary leaf fully grown. Were evaluated the leaf area index (LAI), leaf water potential, commercial and total productivity of ... (Complete abstract click electronic access below) / Orientador: Luiz Carlos Pavani / Coorientador: Arthur Bernardes Cecílio Filho / Banca: Leila Trevizan Braz / Banca: Raimundo Leite Cruz / Mestre
9

Análise numérica de um sistema integrado coletor solar/armazenador térmico /

Santos, Guilherme Henrique Sempionato Souza. January 2007 (has links)
Orientador: Alcides Padilha / Banca: Vicente Luiz Scalon / Banca: Ricardo Fortes de Miranda / Resumo: Este estudo apresenta uma análise numérica dos campos de temperaturas e velocidades d'água durante seu processo de aquecimento via calor sensível no interior de um armazenador térmico cilíndrico, aquecido lateralmente e adiabático em seu topo e base, visando o estudo da condição de operação de um aquecedor de água coletor solar-armazenador integrados (ICSSWH - Integrated Collector-Storage Water Heater). Em uma segunda análise a influência de um defletor interno é estudada pela definição dos campos de velocidades e temperaturas da água. A abordagem numérica é realizada a partir de um modelo bidimensional, transiente, não linear e em coordenadas cilíndricas, discretizada pela técnica de elementos finitos. A construção do modelo é obtida numericamente através de um código computacional desenvolvido em linguagem de programação C. Os resultados numéricos são validados. Análises transientes dos campos de velocidades e temperaturas bem como das temperaturas de mistura e velocidade de carregamento, com e sem parede interna direcionada (defletor interno) são realizadas com a finalidade de estudar a inlfuência da referida parede na convecção livre nessas condições. / Abstract: This study shows a numerical analysis of the temperature and speed fields of water during the process of heating through sensible heat in the interior of a cylindric thermal storage, heated laterally and with adiabatics top and base, in order to study the operational conditions of an integrated collector-storage solar water heater (ICSSWH). In a second analysis a model with an internal baffle is created and temperature and velocity fields are analysed. The numerical study is done taking into consideration a bidimensional, transient non linear research in cylindric coordenates, discretized by the technique of finite elements. Its solution is obtained numerically through a computational code developed in a C programming language. The numerical results are validated. A transient analysis of the spped and temperature fields so as of the mixing temperatures and the charging speed, with or without the infernal baffle are carried out taking into account the aim of studying the influence of the so called wall in the free convection of those conditions. / Mestre
10

Temperatura e umidade de um solo franco arenoso cultivado com milho / Temperature and humidity of a sandy loam soil cultivated with maize

Knies, Alberto Eduardo 01 March 2010 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Water is a key factor for crop yields, and causes major fluctuations in productivity, especially for maize cultivated in southern Brazil. Mulching the soil surface, temperature and soil moisture are factors closely linked and, when handled properly, can provide the increases crop yields. The soil water conservation is an important aspect for more stable and sustainable agricultural production. The purpose of this study was to evaluate changes in water content and dynamics of the temperature in a soil cultivated with maize under different amounts of plant residue on the surface and water regimes. The experiment was conducted in the experimental area of Agricultural Engineering Department, Federal University of Santa Maria, RS, in the crop year 2009/10, inside a rainfall shelter. The experimental design was completely randomized, factorial, with five replications. Factor A consisted of three quantity of plant residue on the soil surface: 0 (zero), 3 and 6 Mg ha-1 of oat (Avena strigosa Schreb). Factor B consisted of two water regimes: with and without irrigation. The volumetric water content (cm3 water cm-3 soil) of soil was determined in the layers: 0-0.1, 0.1-0.25, 0.25-0.55 and 0.55 - 0.85 m, for a set FDR (Frequency Domain Reflectometry). The soil temperature was measured by thermocouples, consisting of a copper wire and the other of constantan, which determined the soil temperature at depths of 0.03, 0.08, 0.15 and 0.30 m. The morphological characteristics of maize plants, as leaf area and cumulative length of leaves were determined with the portable leaf area LI-COR 3000C. The lowest cumulative losses of soil water in the 0-0.1 m were observed in the soil maintained with 6 Mg ha-1 crop residues on the surface, reaching 50% reduction to 100 mm of accumulated reference evapotranspiration (18 days after seeding) compared to bare soil. The use of crop residues on the soil surface did not produce significant changes fenometric in maize plants during the evaluation period. The quantities of 3 and 6 Mg ha-1 crop residues oat deposited on the surface of the soil decreased the maximum temperature and temperature range in the soil. / A água é um fator fundamental à produção das culturas, tendo papel importante nas flutuações de produtividade, principalmente para a cultura do milho no Sul do Brasil. A cobertura morta na superfície do solo, a temperatura e a umidade do solo são fatores intimamente interligados e, quando manejados adequadamente, podem propiciar incrementos à produção das culturas. A conservação da água no solo é um aspecto de relevância para uma produção agrícola mais estável e sustentável. A finalidade deste trabalho foi avaliar as variações no conteúdo de água e na dinâmica da temperatura de um solo cultivado com milho sob diferentes quantidades de resíduo vegetal na superfície e regimes hídricos. O experimento foi realizado em área experimental do Departamento de Engenharia Rural da Universidade Federal de Santa Maria, RS, no ano agrícola de 2009/10, no interior de uma cobertura móvel. O delineamento experimental utilizado foi o inteiramente casualizado, bifatorial, com cinco repetições. O fator A foi constituído de três quantidades de resíduo vegetal sobre a superfície do solo: 0 (zero), 3 e 6 Mg ha-1 de aveia preta (Avena strigosa Schreb). O fator B foi constituído de dois regimes hídricos: irrigado e não irrigado. O conteúdo volumétrico de água (cm3 água cm-3 solo) do solo foi determinado nas camadas de: 0-0,1; 0,1-0,25; 0,25-0,55 e 0,55-0,85 m, por um conjunto FDR (Reflectometria no Domínio de Freqüência). Para avaliação da temperatura do solo, foram utilizados termopares, constituídos de um fio de cobre e de outro de constantan, os quais determinaram a temperatura do solo nas profundidades de 0,03; 0,08; 0,15 e 0,30 m. As características morfológicas das plantas de milho, como área foliar e comprimento acumulado das folhas, foram determinadas com medidor portátil de área foliar LI-COR 3000C. As menores perdas acumuladas de água do solo na camada de 0-0,1 m foram observadas no solo mantido com 6 Mg ha-1 de resíduo vegetal na superfície, chegando a 50 % de redução aos 100 mm de evapotranspiração de referência acumulada (18 dias após a semeadura) comparado ao solo descoberto. A utilização de resíduos vegetais não proporcionou alterações fenométricas significativas nas plantas de milho durante o período de avaliação. As quantidades de 3 e 6 Mg ha-1 de resíduos vegetais de aveia preta depositados sobre a superfície do solo diminuíram a temperatura máxima e a amplitude térmica no solo.

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