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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.
51

Economic costs of conventional surface-water treatment: A case study of the Mcallen northwest facility

Rogers, Callie Sue 15 May 2009 (has links)
Conventional water treatment facilities are the norm for producing potable water for U.S. metropolitan areas. Rapidly-growing urban populations, competing demands for water, imperfect water markets, and uncertainty of future water supplies contribute to high interests in alternative sources of potable water for many U.S. municipalities. In situations where multiple supply alternatives exist, properly analyzing which alternative is the most-economically efficient over the course of its useful life requires a sound economic and financial analysis of each alternative using consistent methodology. This thesis discusses such methodology and provides an assessment of the life-cycle costs of conventional water treatment using actual data from an operating surface-water treatment facility located in McAllen, Texas: the McAllen Northwest facility. This facility has a maximum-designed operating capacity of 8.25 million gallons per day (mgd), but due to required shutdown time and other limitations, it is currently operating at 78% of the designed capacity (6.44 mgd). The economic and financial life-cycle costs associated with constructing and operating the McAllen Northwest facility are analyzed using a newly-developed Excel 2 spreadsheet model, CITY H O ECONOMICS . Although specific results are applicable only to the McAllen Northwest facility, the baseline results of $771.67/acre-foot (acft)/ yr {$2.37/1,000 gallons/yr} for this analysis provide insight regarding the life-cycle costs for conventional surface-water treatment. The baseline results are deterministic (i.e., noninclusive of risk/uncertainty about datainput values), but are expanded to include sensitivity analyses with respect to several critical factors including the facility’s useful life, water rights costs, initial construction costs, and annual operations and maintenance, chemical, and energy costs. For example, alternative costs for water rights associated with sourcing water for conventional treatment facilities are considered relative to the assumed baseline cost of $2,300/ac-ft, with results ranging from a low of $653.34/ac-ft/yr (when water rights are $2,000/ac-ft) to a high of $1,061.83/ac-ft/yr (when water rights are $2,600/ac-ft). Furthermore, modifications to key data-input parameters and results are included for a more consistent basis of comparison to enable comparisons across facilities and/or technologies. The modified results, which are considered appropriate to compare to other similarly calculated values, are $667.74/ac-ft/yr {2.05/1,000 gallons/yr}.
52

When incentives are not enough : a study on how the Philippine government can attract foreign investments in renewable power /

Lipana, Catherine H. January 2008 (has links) (PDF)
Master's thesis. / Format: PDF. Bibl.
53

Comparison of microwave drying and conventional drying of coal

GAO, FENG 24 December 2010 (has links)
The moisture contents of the final coal products from processing plants are often too high and do not meet the requirements of the client. In many cases, drying becomes a necessary step to control the moisture content. Conventional thermal drying is inefficient and is not environmentally friendly. This study investigates the application of microwaves as an alternative heat source for drying coal. The rate of drying was determined by the thermogravimetric analysis (TGA) technique. Several variables that have significant effects on the drying kinetics were investigated, including incident microwave power, initial moisture content and the sample mass. Microwave drying tests were performed under various conditions and the mass change was monitored continuously. The percentage mass loss, moisture fraction and drying rate were obtained for each experimental condition. The final temperature was measured and drying efficiencies were calculated. For comparison purposes, some conventional thermal drying tests were also carried out at temperatures ranging from 130 to 220oC and with coal masses ranging from 10g to 100g. The TGA results show that microwave drying has distinct advantages over conventional drying such as reducing the overall required time and increasing the drying efficiency. A multiple-regression analytical method was used for both microwave and conventional drying to find the best fit model among eleven different types. Finally, the sample mass, which proved to be the most dominant factor in microwave drying, was incorporated into the equation of the best fit model. / Thesis (Master, Mining Engineering) -- Queen's University, 2010-12-23 22:56:04.119
54

Evaluation of SI-HCCI-SI mode-switching using conventional actuation on a CNG engine

Boddez, Jason Bradley Unknown Date
No description available.
55

The case for designing U.S. ground forces to execute expeditionary warfare /

Kim, Young J., January 1900 (has links)
Thesis (M.S.)--Missouri State University, 2009. / "May 2009." Includes bibliographical references (leaves 113-120). Also available online.
56

Estudos de confiabilidade de redes GNSS

Collischonn, Carolina January 2015 (has links)
O principal objetivo dessa dissertação foi estudar a confiabilidade de redes GNSS. Em termos metodológicos foram analisadas redes obtidas pelos seguintes métodos: redes com inclusão de linhas-base repetidas, por posicionamento relativo e pelo Posicionamento por Ponto Preciso (PPP). A rede GNSS utilizada possui seis estações pertencentes a Rede Brasileira de Monitoramento Continuo (RBMC) do Instituto Brasileiro de Geografia e Estatística (IBGE). As estações se localizam no oeste do estado de São Paulo. Para atingir o objetivo do trabalho foram estruturadas as seguintes hipóteses: a inserção de novas linhas-base em uma estrutura de rede GNSS possibilita melhorar a eficiência na detecção de outliers e aumenta a confiabilidade da rede, bem como, existe um limiar de número de linhas-base que a partir dele não se verifica mais melhora na confiabilidade. E, a outra hipótese, é que redes GNSS podem ser formadas a partir do PPP e ter parâmetros de qualidade estimados (de precisão e de confiabilidade), requisito fundamental para o uso em aplicações geodésicas. Com relação a primeira hipótese foi gerado um artigo onde é aplicado o controle de qualidade por meio da teoria de confiabilidade convencional analisando a melhora da confiabilidade a partir da inclusão de linhas-base repetidas em rede GNSS. Primeiramente foi realizado o ajustamento por mínimos quadrados da rede GNSS e calculadas as medidas de confiabilidade: o número de redundância local, a confiabilidade interna, externa e razão tendência-ruído. As linhas-base repetida na rede foram selecionadas a partir da análise de qual observação possuía menor valor de número de redundância local. O ajustamento foi realizado novamente, bem como o cálculo das medidas de confiabilidade. Esse procedimento foi repetido cinco vezes, quando se verificou a estabilização dos resultados. A segunda hipótese resultou no artigo onde foi apresentada uma metodologia de desenvolvimento de rede utilizando dados GNSS processados pelo PPP. Nesse artigo foi aplicada a teoria convencional de confiabilidade para verificar a potencialidade da metodologia apresentada. Diferentes tempos de rastreio foram empregados nos experimentos. O serviço de processamento de PPP utilizado é o fornecido pelo IBGE. A partir dos resultados foram feitas análises para verificar a aplicabilidade da metodologia descrita em rede com dados GNSS de 24, 6 e 4 horas de rastreio. Após o ajustamento, os testes global e o data snooping foram aplicados. Também é analisada a confiabilidade da rede com o objetivo de avaliar o método proposto, além de verificar a influência do tempo de rastreio nos resultados. / The main goal of the present dissertation was to study the reliability of GNSS networks. In methodological terms networks obtained from the following methods were analyzed: networks with including repeated baselines, relative positioning and Precise Point positioning (PPP). The GNSS network used has six stations belonging to the Brazilian Network of Continuous Monitoring (RBMC) of the Brazilian Institute of Geography and Statistics (IBGE), located in the west part of São Paulo. In order to achieve the objective of the study the following hypotheses were structured: the insertion of the new baselines in a GNSS network structure enables to improve the efficiency in detecting outliers and increases network reliability, just like, there is a threshold in the number of baselines in which above these number there is no improvement in the reliability. The other hypothesis is that GNSS networks can be formed from the PPP and have its quality parameters estimated (accuracy and reliability), fundamental requirement for geodetic applications. An article was generated regarding the first hypothesis where the quality control trough the conventional reliability theory was applied to analyze the quality improvement from the inclusion of repeated baselines in GNSS network. First, the least squared adjustment was made and then the reliability measures were calculated, which are: local redundancy number, the internal and external reliability and bias to noise - ratio. The repeated base lines in the network were selected by choosing the observations with lowest number of local redundancy. The adjustment and the calculation of the reliability measures were performed again. When this procedure was repeated five times, the stabilization of the results was observed. The second hypothesis resulted in an article in which a methodology of network development using GNSS data processed by the PPP was presented. In this paper the conventional reliability theory was applied to verify the presented methodology capability. Different occupation times were used in the experiments. The PPP processing service used is provided by the IBGE. From the results, analyses were performed to verify the applicability of the methodology described in network with GNSS data of 24, 6 and 4 occupation. After the adjustment, the global and data snooping tests were applied. The network reliability is also analyzed with the objective of evaluating the proposed method. In addition was verifying the influence of occupation time in the results.
57

Efeito do manejo de solo nos parâmetros agronômicos e energéticos de híbridos de milho transgênico e não transgênico /

Riquetti, Neilor Bugoni, 1985. January 2011 (has links)
Resumo: Os diferentes tipos de preparo de solo para a implantação de culturas devem oferecer condições favoráveis para a semeadura, emergência e desenvolvimento das plantas, porém, apresentam diferenças em relação ao consumo de combustível das máquinas e na compactação do solo, além de poderem interferir nas características agronômicas e na produtividade das culturas instaladas. Diferentes sistemas de produção têm diferentes demandas por energia dependendo do tempo de uso de máquinas e implementos, consumo de combustível, herbicidas e inseticidas. As culturas modificadas geneticamente, seja para resistência a pragas ou herbicidas, geralmente, requerem menor quantidade de energia, devido à redução no número de aplicações de agrotóxicos. O presente trabalho teve por objetivo avaliar os efeitos de diferentes preparos de solo quanto a produtividade de grãos e algumas características das plantas da cultura do milho transgênico e de seu isogênico não transgênico, além da demanda energética exigida por diferentes sistemas de produção. O estudo foi conduzido na safra agrícola 2009/2010 na Faculdade de Ciências Agronômicas - UNESP, localizada no município de Botucatu, SP, em área cultivada com plantio direto há 11 anos. O delineamento utilizado foi o fatorial 3x2, constituído por três métodos de preparo de solo e dois híbridos de milho, transgênico e não transgênico, totalizando seis tratamentos cada um com quatro repetições. Os dados obtidos foram submetidos à análise de variância a 5% de probabilidade e as médias estatisticamente diferentes foram comparadas pelo teste de Tukey a 5% de probabilidade. Os resultados obtidos mostram que, quanto ao tipo de preparo de solo, o sistema de plantio direto e o cultivo mínimo foram os que resultaram em maior produtividade... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The different types of soil tillage for crop implementation should offer favorable conditions for sowing, emergence and development of plants, however, differ in relation to fuel consumption of machinery and soil compaction, and may also interfere with the agronomic characteristics and crop productivity installed. Different production systems have different demands for energy depending on time of use of machinery and implements, fuel, herbicides and insecticides. The genetically modified crops, either for resistance to pests or herbicides generally require less energy due to the reduction in the number of agrochemicals applications. This study aimed to evaluate the effects of different soil tillage systems on grain yield and some characteristics of crop plants of transgenic maize and its isogenic non-transgenic, as well energy demands required by different production systems. The study was performed in the 2009/2010 agricultural season in the College of Agronomic Sciences - UNESP, located in Botucatu, SP, in area cultivated with no-tillage for 11 years. The design was 3x2 factorial, consisting of three methods of tillage and two corn hybrids, transgenic and non-transgenic, with six treatments each with four replications. The obtained data were submitted to analysis of variance at 5% probability and statistically different averages were compared by Tukey test at 5% probability. The obtained results show that, the type of tillage, the no-tillage and the minimum tillage were those that resulted in higher productivity differing statistically of the productivity obtained in the conventional system. Regarding hybrids, productivity showed no statistically significant difference. The systems of tillage and the different hybrids did not interfere in most other characteristics analyzed. The greater energy efficiency... (Complete abstract click electronic access below) / Orientador: Sérgio Hugo Benez / Coorientador: Paulo Roberto Arbex Silva / Banca: Silvio José Bicudo / Banca: Marco Antonio Gandolfo / Mestre
58

Estudos de confiabilidade de redes GNSS

Collischonn, Carolina January 2015 (has links)
O principal objetivo dessa dissertação foi estudar a confiabilidade de redes GNSS. Em termos metodológicos foram analisadas redes obtidas pelos seguintes métodos: redes com inclusão de linhas-base repetidas, por posicionamento relativo e pelo Posicionamento por Ponto Preciso (PPP). A rede GNSS utilizada possui seis estações pertencentes a Rede Brasileira de Monitoramento Continuo (RBMC) do Instituto Brasileiro de Geografia e Estatística (IBGE). As estações se localizam no oeste do estado de São Paulo. Para atingir o objetivo do trabalho foram estruturadas as seguintes hipóteses: a inserção de novas linhas-base em uma estrutura de rede GNSS possibilita melhorar a eficiência na detecção de outliers e aumenta a confiabilidade da rede, bem como, existe um limiar de número de linhas-base que a partir dele não se verifica mais melhora na confiabilidade. E, a outra hipótese, é que redes GNSS podem ser formadas a partir do PPP e ter parâmetros de qualidade estimados (de precisão e de confiabilidade), requisito fundamental para o uso em aplicações geodésicas. Com relação a primeira hipótese foi gerado um artigo onde é aplicado o controle de qualidade por meio da teoria de confiabilidade convencional analisando a melhora da confiabilidade a partir da inclusão de linhas-base repetidas em rede GNSS. Primeiramente foi realizado o ajustamento por mínimos quadrados da rede GNSS e calculadas as medidas de confiabilidade: o número de redundância local, a confiabilidade interna, externa e razão tendência-ruído. As linhas-base repetida na rede foram selecionadas a partir da análise de qual observação possuía menor valor de número de redundância local. O ajustamento foi realizado novamente, bem como o cálculo das medidas de confiabilidade. Esse procedimento foi repetido cinco vezes, quando se verificou a estabilização dos resultados. A segunda hipótese resultou no artigo onde foi apresentada uma metodologia de desenvolvimento de rede utilizando dados GNSS processados pelo PPP. Nesse artigo foi aplicada a teoria convencional de confiabilidade para verificar a potencialidade da metodologia apresentada. Diferentes tempos de rastreio foram empregados nos experimentos. O serviço de processamento de PPP utilizado é o fornecido pelo IBGE. A partir dos resultados foram feitas análises para verificar a aplicabilidade da metodologia descrita em rede com dados GNSS de 24, 6 e 4 horas de rastreio. Após o ajustamento, os testes global e o data snooping foram aplicados. Também é analisada a confiabilidade da rede com o objetivo de avaliar o método proposto, além de verificar a influência do tempo de rastreio nos resultados. / The main goal of the present dissertation was to study the reliability of GNSS networks. In methodological terms networks obtained from the following methods were analyzed: networks with including repeated baselines, relative positioning and Precise Point positioning (PPP). The GNSS network used has six stations belonging to the Brazilian Network of Continuous Monitoring (RBMC) of the Brazilian Institute of Geography and Statistics (IBGE), located in the west part of São Paulo. In order to achieve the objective of the study the following hypotheses were structured: the insertion of the new baselines in a GNSS network structure enables to improve the efficiency in detecting outliers and increases network reliability, just like, there is a threshold in the number of baselines in which above these number there is no improvement in the reliability. The other hypothesis is that GNSS networks can be formed from the PPP and have its quality parameters estimated (accuracy and reliability), fundamental requirement for geodetic applications. An article was generated regarding the first hypothesis where the quality control trough the conventional reliability theory was applied to analyze the quality improvement from the inclusion of repeated baselines in GNSS network. First, the least squared adjustment was made and then the reliability measures were calculated, which are: local redundancy number, the internal and external reliability and bias to noise - ratio. The repeated base lines in the network were selected by choosing the observations with lowest number of local redundancy. The adjustment and the calculation of the reliability measures were performed again. When this procedure was repeated five times, the stabilization of the results was observed. The second hypothesis resulted in an article in which a methodology of network development using GNSS data processed by the PPP was presented. In this paper the conventional reliability theory was applied to verify the presented methodology capability. Different occupation times were used in the experiments. The PPP processing service used is provided by the IBGE. From the results, analyses were performed to verify the applicability of the methodology described in network with GNSS data of 24, 6 and 4 occupation. After the adjustment, the global and data snooping tests were applied. The network reliability is also analyzed with the objective of evaluating the proposed method. In addition was verifying the influence of occupation time in the results.
59

Diferentes densidades de gaiola e suas implicações no comportamento de galinhas poedeiras e na qualidade dos ovos produzidos / Different cage densities and their implications on the behavior of laying hens and the quality of eggs

Maria Amelia Flandres Cabrelon 26 January 2016 (has links)
Objetivou-se com esta pesquisa avaliar o efeito de diferentes densidades de galinhas poedeiras alojadas em gaiolas convencionais (50x45x40 cm) nos índices produtivos, na viabilidade, qualidade dos ovos e comportamento das aves. A pesquisa foi realizada na cidade de Bastos (SP) com duração de 18 semanas. Foram utilizadas 500 aves, da linhagem ISA Brown, distribuídas em 5 tratamentos com 25 repetições cada. Os tratamentos foram: tratamento 1: 6 aves/ gaiola (375,0 cm²), tratamento 2: 5 aves/gaiola (450,0 cm²); tratamento 3: 4 aves/gaiola (562,5 cm²); tratamento 4: 3 aves/ gaiola (750,0 cm²) e tratamento 5: 2 aves/gaiola (1.125,0 cm²). Adotou-se o delineamento inteiramente aleatorizado, este contendo cinco tratamentos e 25 repetições. De acordo com os resultados, verificou-se que o tratamento 1 apresentou as menores médias percentuais de produção quando relacionado aos demais tratamentos, diferindo-se estatisticamente. A viabilidade e qualidade dos ovos, não apresentaram diferença estatística entre os tratamentos. Já com relação ao comportamento das aves foi possível observar que o tratamento 5 (menor densidade) foi o que expressou diferentes comportamentos e diferiu-se estatisticamente dos demais. Observou-se também que, quanto à atividade, o tratamento 5 passou menor parte do tempo \"parado\". De acordo com esses resultados, conclui-se que com o aumento da densidade, ocorreu uma significativa redução na produção e na viabilidade, porém, quanto a qualidade dos ovos, não sofreu influência significativa, em relação aos comportamentos das aves, observouse que os animais expressaram melhor o seu comportamento natural quando estavam em menor densidade, ou seja, maior espaço. / The objective of this research was to evaluate the effect of different densities of laying hens housed in conventional cages (50x45x40 cm) in production rates, viability, quality of eggs and bird behavior. The survey was conducted in the city of Bastos (SP) lasting 18 weeks. They were used 500 birds, ISA Brown hens, distributed in 5 treatments with 25 repetitions each. The treatments were: Treatment 1: 6 / Bird Cage (375.0 cm²), treatment 2: 5 birds / cage (450.0 cm²); treatment 3: 4 birds / cage (562.5 cm²); Treatment 4: 3 birds / cage (750.0 cm²) and treatment 5: 2 / Bird Cage (1125.0 cm²). Adopted a completely randomized design, this containing five treatments and 25 repetitions. According to the results, it was found that the treatment 1 had the lowest average percentage of production when related to other treatments, differing statistically. The viability and quality of eggs, there was no statistical difference between treatments. In relation to the behavior of birds was observed that the treatment 5 (lower density) was expressed that the different behaviors and differed statistically from the others. It was also observed that, as the activity, treatment 5 spent less of their time \"stopped\". According to these results, we conclude that with the consolidation of the cages, it was noticeable that the production and mortality has a significant worsening, as the quality of eggs, there was no influence of the different densities of the conduct of the birds, it is observed that the animals best express their natural behavior when they are in lower density, or larger space.
60

Estudos de confiabilidade de redes GNSS

Collischonn, Carolina January 2015 (has links)
O principal objetivo dessa dissertação foi estudar a confiabilidade de redes GNSS. Em termos metodológicos foram analisadas redes obtidas pelos seguintes métodos: redes com inclusão de linhas-base repetidas, por posicionamento relativo e pelo Posicionamento por Ponto Preciso (PPP). A rede GNSS utilizada possui seis estações pertencentes a Rede Brasileira de Monitoramento Continuo (RBMC) do Instituto Brasileiro de Geografia e Estatística (IBGE). As estações se localizam no oeste do estado de São Paulo. Para atingir o objetivo do trabalho foram estruturadas as seguintes hipóteses: a inserção de novas linhas-base em uma estrutura de rede GNSS possibilita melhorar a eficiência na detecção de outliers e aumenta a confiabilidade da rede, bem como, existe um limiar de número de linhas-base que a partir dele não se verifica mais melhora na confiabilidade. E, a outra hipótese, é que redes GNSS podem ser formadas a partir do PPP e ter parâmetros de qualidade estimados (de precisão e de confiabilidade), requisito fundamental para o uso em aplicações geodésicas. Com relação a primeira hipótese foi gerado um artigo onde é aplicado o controle de qualidade por meio da teoria de confiabilidade convencional analisando a melhora da confiabilidade a partir da inclusão de linhas-base repetidas em rede GNSS. Primeiramente foi realizado o ajustamento por mínimos quadrados da rede GNSS e calculadas as medidas de confiabilidade: o número de redundância local, a confiabilidade interna, externa e razão tendência-ruído. As linhas-base repetida na rede foram selecionadas a partir da análise de qual observação possuía menor valor de número de redundância local. O ajustamento foi realizado novamente, bem como o cálculo das medidas de confiabilidade. Esse procedimento foi repetido cinco vezes, quando se verificou a estabilização dos resultados. A segunda hipótese resultou no artigo onde foi apresentada uma metodologia de desenvolvimento de rede utilizando dados GNSS processados pelo PPP. Nesse artigo foi aplicada a teoria convencional de confiabilidade para verificar a potencialidade da metodologia apresentada. Diferentes tempos de rastreio foram empregados nos experimentos. O serviço de processamento de PPP utilizado é o fornecido pelo IBGE. A partir dos resultados foram feitas análises para verificar a aplicabilidade da metodologia descrita em rede com dados GNSS de 24, 6 e 4 horas de rastreio. Após o ajustamento, os testes global e o data snooping foram aplicados. Também é analisada a confiabilidade da rede com o objetivo de avaliar o método proposto, além de verificar a influência do tempo de rastreio nos resultados. / The main goal of the present dissertation was to study the reliability of GNSS networks. In methodological terms networks obtained from the following methods were analyzed: networks with including repeated baselines, relative positioning and Precise Point positioning (PPP). The GNSS network used has six stations belonging to the Brazilian Network of Continuous Monitoring (RBMC) of the Brazilian Institute of Geography and Statistics (IBGE), located in the west part of São Paulo. In order to achieve the objective of the study the following hypotheses were structured: the insertion of the new baselines in a GNSS network structure enables to improve the efficiency in detecting outliers and increases network reliability, just like, there is a threshold in the number of baselines in which above these number there is no improvement in the reliability. The other hypothesis is that GNSS networks can be formed from the PPP and have its quality parameters estimated (accuracy and reliability), fundamental requirement for geodetic applications. An article was generated regarding the first hypothesis where the quality control trough the conventional reliability theory was applied to analyze the quality improvement from the inclusion of repeated baselines in GNSS network. First, the least squared adjustment was made and then the reliability measures were calculated, which are: local redundancy number, the internal and external reliability and bias to noise - ratio. The repeated base lines in the network were selected by choosing the observations with lowest number of local redundancy. The adjustment and the calculation of the reliability measures were performed again. When this procedure was repeated five times, the stabilization of the results was observed. The second hypothesis resulted in an article in which a methodology of network development using GNSS data processed by the PPP was presented. In this paper the conventional reliability theory was applied to verify the presented methodology capability. Different occupation times were used in the experiments. The PPP processing service used is provided by the IBGE. From the results, analyses were performed to verify the applicability of the methodology described in network with GNSS data of 24, 6 and 4 occupation. After the adjustment, the global and data snooping tests were applied. The network reliability is also analyzed with the objective of evaluating the proposed method. In addition was verifying the influence of occupation time in the results.

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