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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.
31

A transposição do Rio São Francisco como potencial medida de adaptação às mudanças climáticas / Integration Project of the São Francisco River as a potential measure of adaptation to climate change

Nadia Costa Pontes 17 August 2018 (has links)
A região Nordeste, primeira a ser ocupada após a chegada dos portugueses no Brasil no século XVI, possui 53% do seu território sob regime do clima semiárido. Nesse espaço, onde vivem 12 milhões de pessoas, as crises causadas por escassez de água, apontadas como barreiras ao desenvolvimento, são conhecidas há mais de um século, causaram perdas agrícolas, migrações e mortes. A região, de conhecida variabilidade climática, é ainda uma das mais vulneráveis do globo às mudanças climáticas. Até o fim desse século, previsões indicam que a temperatura pode subir 4 C em relação à era pré-industrial, com forte impacto sobre os recursos hídricos e desertificação. Diante desse cenário, medidas que oferecem às populações locais condições de se adaptarem se fazem urgentes. Proposto há mais de um século como solução dos problemas trazidos pela escassez de água no semiárido, a transposição do rio São Francisco passou a ser implantada a partir de 2007 sob nome oficial de Projeto de Integração do rio São Francisco com as Bacias Hidrográficas do Nordeste Setentrional (PISF). Trata-se da maior obra de infraestrutura hídrica do país, projetada para transferir 26,4 m3/s por dois eixos principais, Norte e Leste, o volume transportado pelos canais é destinado principalmente ao consumo humano e dessedentação animal. Esta dissertação tem o objetivo de analisar o Eixo Leste do PISF como potencial medida de adaptação às mudanças climáticas. A estratégia de investigação aplicada nesse trabalho interdisciplinar se enquadra na pesquisa qualitativa, apoia-se em documentos, imagens, entrevistas não estruturadas e visitas de campo. A pesquisa conclui que a distribuição de água feita pelo Eixo Leste do PISF não contribui para que as populações mais vulneráveis do semiárido se adaptem às mudanças climáticas, mas que o projeto tem potencial para se converter em tal medida. / The Brazilian Northeast region, the first to be occupied after the arrival of the Portuguese in the 16th century, has 53% of its territory under a semi-arid climate regime. This space is home to 12 million people, it has been hit by crises caused by water shortages, which are understood as barriers to development. Known by its climatic variability, the semiarid portion of the Northeast is one of the world\'s most vulnerable region to climate change. By the end of this century, predictions indicate that temperature could rise by 4 C as compared to the pre- industrial time, with a strong impact on water resources and desertification. Given this scenario, it is urgent to discuss measures that offer the local population conditions to adapt. Proposed more than a century ago as a solution to the problems brought about by the water scarcity in the semiarid, the project to divert Brazil\'s Sao Francisco river began to be implemented in 2007 under the official name of the São Francisco River Integration Project with the Northern Northeast Hydro Basins (PISF). It is the largest water infrastructure project in the country, designed to transfer 26.4 m3/s through two main axes, Northern and Eastern. The volume transported by the channels is mainly intended for human and animal consumption. This dissertation aims to analyze the Eastern Axis of the PISF of the Northeast of Brazil as a potential adaptation to climate change measure. The research strategy applied in this interdisciplinary work fits the qualitative research, relies on documents, images, unstructured interviews and field visits. The research concludes that the distribution of water by the Eastern Axis of the PISF does not contribute to the adaptation of most vulnerable populations in the semiarid region, but that PISF has the potential to convert to that such measure.
32

Risk and reliability assessment of multiple reservoir water supply headworks systems

Crawley, P. D. (Philip David) January 1995 (has links) (PDF)
Bibliography: p. 474-514.
33

International law on water transfers

Espada, Gildo Manuel January 2007 (has links)
University of Macau / Faculty of Law
34

The decision making process for social issue behaviors : a stakeholder perspective / Katherine Carol Lafreniere

LaFreniere, Katherine Carol, University of Lethbridge. Faculty of Management January 2010 (has links)
This study argues that Stakeholder Theory (Mitchell, Agle, & Wood, 1997) can be applied from the stakeholder‘s perspective in order to understand how stakeholders perceive their claims in an organization and consequently decide how to influence an organization. Using this audience-centric perspective, organizations can influence the stakeholder‘s claims and ultimately how the stakeholder will support the organization. These arguments are supported based on the case of farmers who voted in the 2007 water transfer agreement between the Municipality of Rocky View and the Western Irrigation District (WID). Personal interviews, employing Narrative Research, were conducted to document the participant‘s interpretations. The interview transcripts were analyzed in order to test and expand Stakeholder Theory as well as determine how marketers can use this perspective to successfully target different groups of stakeholders. This understanding contributes to potential management effectiveness because it explains how managers can deal with multiple stakeholder interests. / vii, 82 leaves ; 29 cm
35

Risk and reliability assessment of multiple reservoir water supply headworks systems / by Philip David Crawley.

Crawley, P. D. (Philip David) January 1995 (has links)
Bibliography: p. 474-514. / xli, 601 p. (some folded) : ill., maps (one col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1995
36

Risk and reliability assessment of multiple reservoir water supply headworks systems / by Philip David Crawley.

Crawley, P. D. (Philip David) January 1995 (has links)
Bibliography: p. 474-514. / xli, 601 p. (some folded) : ill., maps (one col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1995
37

Proposição de indicadores de segurança hídrica: seleção, validação e aplicação na bacia hidrográfica do rio Jundiaí-Mirim, Jundiaí - SP, Brasil / Proposition water security indicators: selection, validation and application in the Jundiaí-Mirim river basin, Jundiaí - SP, Brazil

Machado, Fernando Henrique 01 March 2018 (has links)
Submitted by Fernando Henrique Machado (fernandomtb@hotmail.com) on 2018-04-23T13:30:20Z No. of bitstreams: 1 FHM - Tese 132 [PD].pdf: 9073445 bytes, checksum: 558a93dca350999137782573a2b01e5b (MD5) / Rejected by Bruna Bacalgini null (bruna@sorocaba.unesp.br), reason: Prezado, Solicitamos que realize correções na submissão seguindo as orientações abaixo: O pdf não pode estar protegido, por favor, faça a submissão novamente com arquivo pdf não protegido. Agradecemos a compreensão. on 2018-04-23T14:00:52Z (GMT) / Submitted by Fernando Henrique Machado (fernandomtb@hotmail.com) on 2018-04-23T14:39:49Z No. of bitstreams: 1 FHM - Tese 132 [PD].pdf: 9054390 bytes, checksum: 858ba049e3608953cf364a4045e9e325 (MD5) / Approved for entry into archive by Bruna Bacalgini null (bruna@sorocaba.unesp.br) on 2018-04-23T14:44:42Z (GMT) No. of bitstreams: 1 machado_fh_dr_soro.pdf: 9054390 bytes, checksum: 858ba049e3608953cf364a4045e9e325 (MD5) / Made available in DSpace on 2018-04-23T14:44:42Z (GMT). No. of bitstreams: 1 machado_fh_dr_soro.pdf: 9054390 bytes, checksum: 858ba049e3608953cf364a4045e9e325 (MD5) Previous issue date: 2018-03-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As bacias hidrográficas localizadas em áreas densamente ocupadas e industrializadas sofrem diferentes pressões antrópicas, situação que compromete a qualidade e quantidade da água. Esse cenário, peculiar nas bacias hidrográficas dos rios Piracicaba, Capivari e Jundiaí (BH-PCJ), reflete também na sub-bacia hidrográfica do rio Jundiaí-Mirim (BH-JM), responsável pelo fornecimento de 95% da água consumida por Jundiaí-SP. Todavia, a vazão produzida nesta bacia é insuficiente para atender as demandas do município, necessitando da reversão sazonal das águas do rio Atibaia. Diante desse quadro de estresse hídrico, este estudo visou propor e analisar um conjunto de indicadores de segurança hídrica visando a melhoria da capacidade de planejamento e gestão dos recursos hídricos da BH-JM. Assim, utilizou-se de uma abordagem metodológica pautada na seleção, validação, aplicação e estruturação de indicadores de segurança hídrica em um modelo de causa-efeito. Os indicadores foram submetidos à avaliação por meio de um painel multidisciplinar de especialistas utilizando-se o método Delphi. Os indicadores validados pelo painel foram discutidos e, posteriormente, sistematizados a fim do estabelecimento das diretrizes. Os indicadores selecionados foram: (i) oferta de água; (ii) reservatórios de água; (iii) rede de distribuição; (iv) perdas na distribuição de água potável; (v) transposição de água; (vi) qualidade físico-química e biológica da água; e (vii) políticas públicas. Os principais resultados foram: (i) a série histórica analisada apontou um crescimento populacional de 1,8% a.a., conquanto a produção de água tratada cresceu a taxas inferiores (1,2% a.a.), onde verificou-se a redução constante do consumo per capta de 248 L hab.-1 dia-1 para 203 L hab.-1 dia-1 em um período de 17 anos; (ii) as áreas ocupadas por lagos e reservatórios foram ampliadas em 703% em um período de 4 décadas, sendo a maior área representada pelo reservatório de abastecimento público, do qual estimou-se receber uma carga de sedimentos de 1,5 mil t ano-1 ; (iii) o crescimento geométrico da rede de distribuição aumentou a taxas de 3,1% a.a., refletindo no aumento linear do número de ligações ativas de água; (iv) as perdas médias do sistema de distribuição de água potável encontra-se na ordem de 34% ao longo de quase duas décadas, representando perdas de aproximadamente 17,6 milhões de m3 ano-1 ou R$ 38,3 milhões ano-1 ; (v) uso cada vez mais frequente das águas revertidas do rio Atibaia, medida que pode emergir inúmeros desdobramentos e conflitos futuros pelo uso da água na região; (vi) alterações adversas na qualidade físico-química da água da BH-JM em decorrência da transposição, como o aumento na concentração de íons metálicos, turbidez, cloreto, dentre outros; (vii) identificou-se um amplo aparato jurídico-ambiental relacionadas à BH-JM, porém com baixa eficácia jurídica em suas aplicações. Em face dos resultados, 49 diretrizes de gestão foram propostas. Desse modo, a abordagem metodológica empregada revelou-se adequada e replicável para outras bacias, uma vez que: a partir do método Delphi foi possível estabelecer critérios de seleção de indicadores considerando a problemática em análise; a discussão individual dos indicadores permitiu uma melhor compreensão das dinâmicas envolvidas em cada indicador; a estruturação dos indicadores em um modelo-causal permitiu a sistematização das informações e, consequentemente, contribuiu para o estabelecimento das diretrizes. / The river basins located in densely occupied and industrialized areas are subject to different anthropogenic pressures, a condition that compromises directly the quality and quantity of water resources. This situation is common in the Piracicaba, Capivari, and Jundiaí river basins (BH-PCJ), southwestern Brazil, as well as in the Jundiaí-Mirim river basin (BH-JM) (sub-basin of the Jundiaí river). The BH-JM is a strategic area due to supply 95% of the raw water consumed by Jundiaí-SP. However, the available water flow in this basin is not enough to meet the local demands. This fact led to the need for seasonal interbasin water transfer from the Atibaia river. In view of this water stress scenario, this study aimed to propose and analyze a set of water security indicators for improving the planning and management capacity of the BHJM water resources. Therefore, a methodological approach based in selection, validation, application and structuring of water safety indicators was used in a cause-effect model. The indicators were submitted to the assessment through a multidisciplinary panel of experts using the Delphi method. The valid indicators from the panel were well discussed and, posteriorly, systematized for purpose of establishment of guidelines. The selected indicators were: (i) water supply; (ii) water reservoir; (iii) drinking water distribution system; (iv) drinking water losses in the distribution system; (v) interbasin water transfer; (vi) physical-chemical and biological water quality; (vii) public policies. The main results were: (i) the historical series analyzed showed a population growth rate of 1.8% p.a., while the potable water production was 1.2% p.a., where there was a constant reduction of consumption of 248 L inhabitant-1 day-1 to 203 L inhabitant-1 day-1 in 17 years; (ii) the areas occupied by lakes and reservoirs in BH-JM were increased by 703% in 4 decades, the largest area represented by the public supply reservoir, from which it was estimated that a sediment load of 1,5 thousand tons-1 ; (iii) the geometric growth of the distribution network was of 3.1% p.a., reflecting the linear increase in the number of hydrometric water connections; (iv) the average of drinking water losses in the distribution systems was around 34% over almost two decades, representing losses of about 17.6 million m3 year-1 or R$ 38.3 million year- 1 ; (v) increasingly frequent use of the interbasin water transfer from Atibaia river, a measure that may result in many unfolding and future conflicts over the use of water in the region; (vi) adverse changes in the physical-chemical quality of BH-JM water due to interbasin water transfer, such as the increase in the concentration of metallic ions, turbidity, chloride, among others; (vii) an ample environmental legislative framework related to BH-JM was identified, but with low legal effectiveness in their applications. In view of the results, 49 management guidelines were proposed. Therefore, the methodological approach used demonstrated to be adequate and replicable for other river basins, once that: the Delphi method developed allowed to set up criteria of indicators selection considering the research questions analyzed; the indicators discussion allowed a better understanding of the dynamics involved in each indicator; the indicators structuring in a causal model allowed the information systematization and, thus, it is contributed to the establishment the management guidelines. / Capes-DS
38

Otimização da potência de bombeamento aplicado ao planejamento do sistema hidrotérmico de potência via colônia de formigas

Alencar, Thiago Ribeiro de January 2017 (has links)
Orientadora: Profa. Dra. Patrícia Teixeira Leite Asano / Tese (doutorado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, 2017. / A área do setor elétrico que trata das necessidades energéticas por parte das usinas, de forma coordenada, é chamada de Planejamento da Operação de Sistemas Hidrotérmicos de Potência. Esta área tem como finalidade principal encontrar uma política operativa que forneça energia elétrica ao sistema, em um determinado período, com confiabilidade e por um custo mínimo. Sendo assim com a intenção de colaborar com está área, a Tese desenvolvida teve como objetivo principal aplicar a técnica de otimização de colônia de formigas para minimizar a potência de bombeamento através da definição do melhor caminho para construção de tubulações de transferência de água entre dois pontos. Para isso uma nova ferramenta computacional (programa IarAI) foi proposta e implementada considerando os dados georreferenciados de entrada, sendo o relevo da região e restrições ambientais. O programa IarAI foi implementado nas linguagens Java e JavaScript. Além disso, o IarAI é composto por quatro módulos que utilizam como técnicas de otimização as Colônias de Formigas e Algoritmos Genéticos. A metodologia e programa foram validados através de dois estudos de casos. O primeiro foi composto por três pontes que ligavam o ninho até a comida com um espaço de busca de 1200 m (40 pontos) x 480 m (16 pontos). O segundo caso teste foi aplicado no curso natural do rio Pinheiros na cidade de São Paulo com um espaço de busca de 34.710 m (1.157 pontos) x 17.960 m (568 pontos). Finalmente, os resultados apresentados demonstram a aplicabilidade da metodologia e algoritmo proposto. / The area of the electricity sector that addresses the energy needs of the plants, in a coordinated way, is called Operation of Hydrothermal Power Systems. This area has as main objective to find an operative policy that provides electrical energy to the system, in a certain period, with reliability and for a minimum cost. The main objective of this thesis was to apply the ant colony optimization technique to minimize pumping power by defining the best path for the construction of water transfer pipes between two points. A new computational tool (IarAI program) was proposed and implemented considering the georeferenced input data, being the relief of the region and environmental restrictions. The IarAI program was implemented in Java and JavaScript languages. In addition, the IarAI is composed of four modules that use as optimization techniques the Ant Colony and Genetic Algorithms. The methodology and program were validated through two case studies. The first one consisted of three bridges that connected the nest to the food with a search space of 1200 m (40 points) x 480 m (16 points). The second test case was applied in the natural course of the Pinheiros river in the city of São Paulo with a search space of 34,710 m (1,157 points) x 17,960 m (568 points). Finally, the presented results demonstrate the applicability of the methodology and proposed algorithm.
39

Unit commitment model development for hydropower on the Day-Ahead spot market.

Radulesco, Romain January 2020 (has links)
In the aftermath of the liberalization of European Energy Markets in the 2000s, Power Exchange platforms have constantly evolved towards more integrated and competitive designs, where quality forecasts and effective optimization strategies play decisive roles. This study presents the development of a hydropower scheduling optimization algorithm for the Day-Ahead spot market using Mixed Integer Linear Programming (MILP). This work was supported by the hydro asset management team of ENGIE Global Energy Markets (GEM) located in Brussels.  The model developed is focusing on the optimization of Coindre Hydraulic Power Plant (HPP), located in the highlands of Massif Central in France. With the combined water discharge of its two interconnected reservoirs, Grande-Rhue and Petite-Rhue, the powerhouse can reach up to 36 MW of power output capacity. The two reservoirs are located kilometres apart from each other and have different storage capacities and catchment areas. The reservoirs naturally exchange water due to the level difference along an interconnection pipe. Maximum power output is limited by water level differences in both reservoirs, which makes modelling complicated. These operational constraints are a limiting factor in terms of operability, as a result the scheduling process is a non-trivial task and is time-consuming.  A framing study of the power plant was conducted over a hydraulic year to identify the governing parameters of the model. The multi-reservoir nature of the optimization problem oriented the model development towards a Mixed Integer Linear Formulation. After experimenting with different solvers, Gurobi 28.1.0 was chosen for its performance in the Branch and Cut Algorithm for the power scheduling task.  The performance of the new model has been validated by re-running the model on past production plans, results show that reservoir volume errors are less than 5% of their respective capacities on a 5 days’ time-horizon. After backtesting it was found that the new optimization strategy results in higher revenue for the plant due to the optimized operation at higher average energy prices. The results also bring out the importance of proper valve actuation in the optimization strategy, as well as the need for future studies. / Till följd av liberaliseringen av de europeiska energimarknaderna under 2000-talet har energiföretagen och elbörserna ständigt utvecklats mot mer integrerade och konkurrenskraftiga lösningar, där kvalitetsprognoser och effektiva optimeringsstrategier spelar avgörande roller. Detta examensarbete presenterar utvecklingen av en algoritm för optimering av vattenkraftplaneringen på Day-Ahead elmarknaden med hjälp av en matematisk modell av typen Mixed Integer Linear Programming (MILP). Arbetet initierades av och utfördes hos ENGIE Global Energy Markets (GEM) i Bryssel.  Modellen som utvecklats är tänkt att optimera Coindre vattenkraftverk, som ligger på höglandet inom Massif Central i Frankrike. Med det kombinerade vattenutsläppet från dess två fördämningar, Grande-Rhue och Petite-Rhue, kan kraftverket leverera upp till 36 MW el netto till elnätet. Vattenreservoarerna ligger flertalet kilometer ifrån varandra och har mycket olika kapacitet och upptagningsområden. Båda reservoarerna är kopplade till varandra genom det gemensamma tilloppsröret till kraftverket, där en reglerventil finns endast vid Petite-Rhue. Vatten kan växlas naturligt mellan de två dammarna när ventilen är öppen på grund av skillnaden i varderas vattennivå. Den maximala effekten från kraftverket är begränsad av vattennivåerna i båda reservoarerna vilket gör optimeringsmodelleringen komplicerad. Dessa operationella begränsningar är mycket hindrande vad gäller valet av driftsregim, eftersom kalkylering av driftsplaneringen blir en svår och tidskrävande uppgift.  En ramstudie av vattenkraftverket genomfördes under ett typiskt hydrauliskt år för att identifiera modellens styrparametrar. Den möjliga vattenöverföringen mellan de två dammarna orienterade modellutvecklingen mot en Mixed Integer Linear Programming (MILP) formulering. Efter att ha experimenterat med olika kalkylverktyg valdes Gurobi 28.1.0 för sin bra prestation i lösningen av Branch and Cut-algoritmen.  Systemets hydraulik har validerats genom att injicera realiserade produktionsplaner som input till modellen. Resultaten visar att volymfelet är mindre än 5% av deras respektive kapacitet under en 5-dagars tidshorisont. Efter tvärstester mot historiska data konstaterades det att den nya optimeringsstrategin resulterar i bättre genomsnittliga elpriser på varje kWh inmatad till nätet och högre intäkter för kraftverket. Resultaten visar också på vikten av korrekt ventilmanövrering i optimeringsstrategin.  Modellen körs i rimliga beräkningstider och redan används i den dagliga optimeringen av Coindre kraftverket, vilket sparar mycket tid. Specifika exempel på den optimerade prestandan och framtida förbättringar hittas i slutet av denna rapport.
40

The genetic integrity of Labeo capensis and L. umbratus (Cyprinidae) in South Africa in relation to inter-basin water transfer schemes

Ramoejane, Mpho January 2011 (has links)
The Orange-Fish and Cookhouse tunnels that are part of a major inter-basin water transfer scheme (IBT) act as a pathway for several fish species from the Orange River system to enter the Great Fish and Sundays River systems in South Africa. These include Labeo capensis and L. umbratus. Labeo capensis was restricted to the Orange River system before the inter-basin water transfer scheme. Labeo umbratus occurred naturally in the Orange River and in southern flowing river systems. Previous studies showed that the two species hybridise in Hardap Dam, located in a tributary of the Orange River system in Namibia. There are also unconfirmed reports of hybrids from Darlington Dam on the Sundays River system. The aim of the thesis was to confirm hybridisation in Hardap Dam, assess whether hybridisation between L. capensis and L. umbratus has occurred in Darlington Dam and to gain a better understanding of the diversity of these two species. Morphology (morphometrics and meristics), a nuclear S7 intron and the mitochondrial cytochrome ♭ gene were used to assess for hybridisation. A total of 275 specimens were analysed from across the geographical range of the two species. The two species could be distinguished using morphometrics (dorsal fin base, interorbital width and operculum to eye distance) and meristics (lateral line, origin of the dorsal fin to lateral line, origin of the pelvic fin to lateral line and caudal peduncle scale counts) characters. Hybrids from Hardap and Darlington dams were placed between the two species clusters. Labeo umbratus from the Orange River and southern flowing rivers formed a single cluster. The two species could also be distinguished from each other with six nuclear DNA mutations and hybrids were heterozygous at such sites in both dams. Labeo umbratus populations from the Orange River and southern flowing rivers (Gouritz, Gamtoos, Sundays, Bushmans, Great Fish and Nahoon) formed a single lineage. Analysis of mitochondrial DNA, however, revealed that L. umbratus populations from the Orange River and southern flowing rivers were two lineages that differ from each other by 5 mutations. Labeo capensis could be differentiated from both these lineages. Being maternally inherited, mitochondrial DNA did not reveal hybridisation, but ten specimens with L. capensis haplotypes were found in the Darlington Dam. In Hardap Dam, however, it appears that only L. capensis mitochondrial DNA haplotypes persist, despite morphological and nuclear DNA analysis suggesting that both morphs and hybrids of the two species occur. The genetic integrity of these Labeo species has therefore been compromised in at least Hardap and Darlington dams. The Great Fish and Sundays populations are considered to be under threat of complete introgression. The Kat River and Slagboom Dam populations that were isolated before the IBTs have to remain isolated to protect the genetic integrity of the southern lineage of L. umbratus in these two systems.

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