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

Kinzua Dam: a Study in the Congressional Disruption, Relocation-Resettlement, and Rehabilitation of the Seneca Nation of Indians

Verelst, Robert 01 1900 (has links)
This thesis embraces four major topics coinciding with the four considerations designated in President John F. Kennedy's letter to President Basil Williams of the Seneca Nation and the reactions to those items generated during numerous hearings of the House Subcommittee on Indian Affairs. The four topics covered in the President's letter include the possibility of acquiring adjacent property, commonly referred to as "in lieu of" lands, to replace the Indian real estate taken for the Allegheny Reservoir; a review of the reservoir's recreational potential for the benefit of the Seneca Nation; special damages accruing to the Senecas for the loss of their land; and relocation and resettlement.
132

The importance of hydropower in relation to the achievement of the SDGs in Bhutan

Fröstad, Danielle January 2019 (has links)
In order to have a successful outcome and to achieve the Sustainable Development Goals by 2030, the development of the hydropower sector is important. This as the hydropower contributes to the socioeconomic development and economic growth, as well as to have an efficient implementation of the SDGs. Nevertheless, the desired outcome of a hydropower development, which in fact will contribute to the other sectors. Thereby, dam governance is important in the success and an important mechanism as to find the balance in the hydropower projects. Since a good dam governance has the potential to create the achievement in both a hydropower development and Agenda 2030.  In relation to the research questions of this study, the importance of dam governance is discussed and analyzed in the success of a hydropower development and in the relation to the implementation of the SDGs.
133

A Comparison of DEM-based methods for fluvial terrace mapping and sediment volume calculation: Application to the Sheepscot River Watershed, Maine

Hopkins, Austin Jeremy January 2014 (has links)
Thesis advisor: Noah P. Snyder / Thesis advisor: Gail Kineke / Fluvial terraces form in both erosional and depositional landscapes and are important recorders of land-use, climate, and tectonic history. Terrace morphology consists of a flat surface bounded by valley walls and a steep-sloping scarp adjacent to the river channel. Combining these defining characteristics with high-resolution digital elevation models (DEMs) derived from airborne light detection and ranging (lidar) surveys, several methods have been developed to identify and map terraces. This research introduces a newly developed objective terrace mapping method and compares it with three existing DEM-based techniques to determine which is most applicable over entire watersheds. This work also tests multiple methods that use lidar DEMs to quantify the thickness and volume of fill terrace deposits identified upstream of dam sites. The preliminary application is to the Sheepscot River watershed, Maine, where strath and fill terraces are present and record Pleistocene deglaciation, Holocene eustatic forcing, and Anthropocene land-use change. Terraces were mapped at four former dam sites along the river using four separate methodologies and compared to manually delineated area. The methods tested were: (1) edge detection using MATLAB, (2) feature classification algorithms developed by Wood (1996), (3) spatial relationships between interpreted terraces and surrounding natural topography (Walter et al., 2007), and (4) the TerEx terrace mapping toolbox developed by Stout and Belmont (2013). Thickness and volume estimates of fill sediment were calculated at two of the study sites using three DEM-based models and compared to in situ data collected from soil pits, cut bank exposures, and ground penetrating radar surveys. The results from these comparisons served as the basis for selecting methods to map terraces throughout the watershed and quantify fill sediment upstream of current and historic dam sites. Along the main stem and West Branch of the Sheepscot River, terraces were identified along the longitudinal profile of the river using an algorithm developed by Finnegan and Balco (2013), which computes the elevation frequency distribution at regularly spaced cross-sections normal to the channel, and then mapped using the feature classification (Wood, 1996) method. For terraces upstream of current or historic dam sites, thickness and volume estimates were calculated using the two best performing datum surfaces. If all analyzed terraces are composed of impounded sediment, these DEM-based results suggest that terraces along the main stem and West Branch of the Sheepscot River potentially contain up to 1.5 x 106 m3 of fill. These findings suggest powerful new ways to quickly analyze landscape history over large regions using high-resolution, LiDAR DEMs while relying less heavily on the need for detailed and costly field data collection. / Thesis (MS) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Geology and Geophysics.
134

Hydrogeological characteristics of Hartbeespoort Dam

Davis, Aqueelah January 2017 (has links)
Thesis (M.Sc. (Hydrogeology))--University of the Witwatersrand, Faculty of Science, School of Geosciences, 2017. / Hartbeespoort Dam, the source of irrigation and potable water for the local community of Hartbeespoort area is a vulnerable water resource. The aim of this research was to evaluate the interaction between dam water and groundwater as well as characterise the hydrochemical data from metals and tritium. The former was done through the application of environmental isotopes and the implementation of a long term water balance, while the latter used hydrochemical data to define the spatial distribution of metals and tritium. The results indicated that the dam water is separated from the groundwater in winter. Two sources of mixing were recognized to have occurred downstream of the dam in 2015 but not in the Hartbeespoort dam area. These were identified as artificial through the runoff of agricultural water that was abstracted from the dam and through the pumping of water near the fault. Higher than normal tritium concentration indicated that contamination comes through the Crocodile River after the fault connecting the river to Pelindaba, the nuclear power generation plant south of Hartbeespoort Dam in the Broederstroom area. The Crocodile River showed that the contamination of water by lead, 22.11ppb in summer and 3.8 ppb in winter, and cadmium,2.2 ppb in winter. The Magalies River feeds the dam with copper. All metals accumulate at the dam wall and settles in the sediment, diluting the downstream water. Boreholes near the dam and spring along the fault are vulnerable to contamination. The water balance estimation resulted 18 345 472m3, with a 3.9% error, gain of water to the dam from the groundwater greater than the amount exiting the dam to through groundwater. The groundwater entering the dam is estimated to be 32 517 704m3. The groundwater exiting the dam is estimated at 14 172 232m3. The difference in groundwater showed a decrease of 10 000 000m3 over the 15 year period from 1st October 2000 until the 30th September 2015. Consequently, these results show an increased stress placed on the groundwater presumably due to an increase in groundwater abstraction from agriculture and the expanding mining area. / GR2018
135

Estimating water loss from the Renoster River, Free State province, South Africa

Brown, Fred Herman 17 November 2006 (has links)
Faculty of Engineering School of Civil and Enviromental Engineering 9308302w fredb@ananzi.co.za / The Renoster River is a minor left-bank tributary of the Vaal River located some 120 km south-west of Johannesburg in the Free State Province of South Africa. The river is dammed by the Koppies Dam, which divides the river into upper and lower basins. No water is released directly from the Koppies Dam into the Renoster River channel except as a protective measure during natural flooding events. Irrigation releases are made through a separate canal system. The lower Renoster River was modeled as a series of channels, crossing four quaternary catchments. Hydraulic routing was used to estimate potential flow losses for discrete flow events. Out-of-bank flow was found to occur when flow exceeded 300 m3/s. A Pitman monthly rainfall-runoff hydrologic model was used to model longer term historical streamflow data and associated losses. Flow losses for individual flood events along the lower Renoster River were found to vary between 3% and 17%. For a longer term constant flow regime, losses can be expected to range between 10% and 40%. Based on both the hydraulic and hydrologic models, the primary cause of flow loss was found to be evaporation, with insignificant transpiration and transmission losses. For eighty years flow in the lower Renoster River has been artificially controlled. Within that time period the river has adjusted itself to the imposed anthropogenic flow regime. Water losses associated with planned releases into the lower Renoster River can be minimized by using a high discharge rate, to a maximum of 300 m3/s, combined with larger volumetric flows. Evaporation losses can be significant, and release strategies will need to take this into consideration.
136

Aspectos hidrobiológicos do complexo de represas Paraibuna-Paraitinga, São Paulo, com ênfase na comunidade fitoplanctônica / HYDROBIOLOGICAL ASPECTS OF PARAIBUNA AND PARAITINGA DAMS, SÃO PAULO, WITH EMPHASIS ON PHYTOPLANKTON COMMUNITY

Matos, Janara de Camargo 02 March 2010 (has links)
As águas continentais existem em menor quantidade na superfície terrestre e apresentam grande importância para a sobrevivência dos seres vivos, motivo pelo qual a preocupação com sua qualidade aumenta a cada dia. As represas de Paraibuna e Paraitinga, localizadas no município de Paraibuna, São Paulo, totalizam 224 km2 de extensão de espelho d´água, com função atual de geração de energia elétrica. Com o objetivo de analisar a qualidade da água destas represas, o presente trabalho apresenta um diagnóstico físico, químico, bem como biológico, no qual foi utilizada a comunidade fitoplanctônica e cálculos de índices de qualidade. Foram realizadas quatro coletas em nove pontos de amostragem distribuídos ao longo das represas. As análises físicas e químicas da água demonstraram baixas concentrações de nutrientes como nitrato (média 0,42 +/- 0,23 mg.L-1) e fosfato (<0,05 mg.L-1). A maior parte dos metais e elementos-traço analisados mostraram-se dentro dos limites estabelecidos pela legislação federal. O elemento fósforo apresentou valores acima (média 0,0293 +/- 0,0153 mg.L-1) do estabelecido pela resolução CONAMA 357/05 (0,020 mg.L-1) em todos os pontos de amostragem no mês de maio, porém este fato pareceu não influenciar a densidade fitoplanctônica. Altos valores de oxigênio dissolvido e transparência, baixos valores de turbidez, condutividade e sólidos dissolvidos, pH próximo à neutralidade, em conjunto com altos índices de diversidade e baixos índices de dominância fitoplanctônica, com predomínio de clorofíceas, demonstraram que as represas estudadas ainda mantêm características de ambiente aquático preservado. Porém, a presença, ainda que em baixas densidades, de cianofíceas e a existência de atividades de monocultura e pecuária no entorno destas represas merecem especial atenção no que tange ao seu correto manejo para que não se tornem fatores prejudiciais à qualidade daquelas águas. / The inland waters are less on the Earth\'s surface and are extremely important for the survival of living things, why the concern for quality increases daily. The dams Paraibuna and Paraitinga, located in Paraibuna city, state of São Paulo, totaling 224 km2 of extension of water surface, with the current function of generating electricity. In order to analyze the water quality of these dams, this paper presents a diagnostic physical, chemical, and biological, which was used in the phytoplankton community and calculation of quality indexes. Four samples were taken at nine sampling points distributed along the dams. The physical and chemical analysis of water showed low concentrations of nutrients such as nitrate (mean 0,42 +/- 0,23 mg.L-1) and phosphate (<0,05 mg.L-1). Most metals and trace elements analyzed were within the limit established by federal law. The element phosphorus (mean 0,0293 +/- 0,0153 mg.L-1) is presented above the values established by CONAMA Resolution 357/05 (0,020 mg.L-1) on all sampling points in the month of May, but this fact did not seem to influence the phytoplankton amount. High levels of dissolved oxygen and transparency, low levels of turbidity, conductivity and dissolved solids, pH close to neutrality, together with high diversity and low dominance of phytoplankton, with a predominance of green algae, showed that the dams still retain features of aquatic environment preserved, which suffer little influence of anthropogenic factors. However, the presence, even at low densities, of cyanobacteria and the existence of plantations and livestock activities in the borders of these dams deserve special attention in terms of their correct management to not become harmful factors to the quality of those waters.
137

Avaliação da influência do regime de fluxo no comportamento geotécnico de uma barragem de rejeito alteada pelo método de montante. / Evaluation of the flow scheme influence in the geotechnical behavior of a tailing dam heightened through the upstream method.

Silva, João Paulo de Sousa 20 October 2014 (has links)
A presente pesquisa faz uma avaliação da influenciado regime de fluxo na estabilidade de uma barragem construída pela disposição hidráulica de rejeitos. Usualmente, essas estruturas são avaliadas com modelos de equilíbrio limite adotando-se, de modo simplificado, uma superfície freática em um regime hidrostático. No entanto, em casos em que a condutividade hidráulica da fundação ou de camadas na base do aterro é relevante em relação à dos rejeitos, o fluxo se torna verticalizado e o gradiente significativo, portanto, a premissa de regime hidrostático se torna não válida. Com o objetivo de avaliar a influência desses fatores, foram realizadas análises numéricas, simulando condições de fluxo e seus reflexos nos fatores de segurança. Ademais, foi desenvolvida uma extensa análise de dados e cálculos no estudo de caso de uma barragem, com expectativa de ampliar a vida útil de uma Planta de beneficiamento de minério de ferro. Ao se incorporar a real distribuição de pressões neutras, medidas na barragem, concluiu-se que o seu Fator de Segurança era cerca de 20% maior do que o obtido em cálculos simplificados, que desconsideram o regime de fluxo descendente, admitido, por hipótese, na barragem em estudo. Alguns comentários quanto à segurança à liquefação foram feitos, exceto a liquefação dinâmica, que foge do escopo desse trabalho. / The present research evaluates the influence of the foundations permeability in the scheme of flow and in the stability of a dam built through the hydraulic tailings disposal. Usually, these structures are evaluated with models of equilibrium limit, considering, in a simplified way, a phreatic surface in a hydrostatic scheme. However, in cases in which the foundations hydraulic conductivity is relevant when related to the tailings, the flow becomes verticalized and the gradient becomes significant. Therefore, the hydrostatic scheme premise becomes not valid. With the purpose of evaluating the influence of these factors, numerical analysis were made, simulating flow conditions and their influence in the factor of safety. Moreover, an extensive data and calculations analysis was developed in the case study of a dam, with the expectation of increasing the lifetime of an ore mining beneficiation plan. When incorporating the actual distribution of porepressure, measured at the dam, it was concluded that the safety factor of the dam was about 20% higher than that obtained for simplified calculations, that disregard the downward flow regime, admitted in the dam under study. Some comments about the safety of liquefaction were made, except the dynamic liquefaction, beyond the scope of this work.
138

Monitoramento de barragens de contenção de rejeitos da mineração. / Monitoring tailings dams of the mining.

Machado, William Gladstone de Freitas 03 December 2007 (has links)
Esta dissertação é uma contribuição, através de uma pesquisa bibliográfica, sobre o tema instrumentação e monitoramento em empreendimentos de barragens de rejeitos da mineração. Nesta pesquisa apresentam-se os objetivos básicos da instrumentação de barragens e suas características técnicas, metodologia construtiva das barragens de rejeitos e seu monitoramento através de auscultação da instrumentação. Como limitação do trabalho, devido à variedade de instrumentos que podem ser instalados em uma barragem, buscou-se pesquisar os instrumentos de medição de deslocamentos e controle de fluxo percolante, sendo os mais utilizados em barragens de terra e rejeitos. Justifica-se este tema motivado pelos últimos acidentes ocorridos em barragens de contenção de rejeitos, enfatizando a importância e a necessidade permanente da melhoria das condições de segurança e monitoramento das barragens brasileiras. Estes acidentes causam danos à população do entorno da barragem, econômicos ao empreendedor e ambientais. Como resultado obtido nesta pesquisa pode-se concluir que propiciou conhecimento atualizado ao meio técnico nacional de barragens. / This dissertation is a contribution, through a bibliographical research, on the subject of instrumentation and monitoring in enterprises of tailings dams. This research presents the basic objectives of the instrumentation of dams, their technical characteristics, the construction methodology of tailings dams and their monitoring through auscultation of the instrumentation. Due to the variety of instruments that can be installed in a dam, this work was limited to the analysis of two segments, instruments of measurement displacements and those for controlling percolation flow, which are the most commonly used in earth and tailings dams. This study is justified due to recent accidents occurring in tailings dams, which stress the importance and the permanent necessity of the improvement in security and monitoring conditions of Brazilian dams. These accidents cause social, economic and environmental damages to the enterprise. As a result of this research it can be concluded that it contributed with up-to-date knowledge to the national technical dam sector.
139

Mapeamento de áreas suscetíveis a inundação por rompimento de barragem em ambiente semiárido / Mapping of areas susceptible to flooding by dam breaking in semi-arid environment

Oliveira, Alarcon Matos de 11 October 2016 (has links)
Barragens pode ser considerando como risco potencial, o conhecimento da forma provável que se comportaria uma onda de cheia (escoamento crítico), provocado pelo rompimento de barragem é muito importante para as populações que residem à jusante do barramento, como acontece em São José do Jacuípe. Isto por que em caso de rompimento torna-se necessário existir plano de evacuação para área afetada a jusante. Neste sentido destaca-se a utilização de modelos ambientais aliados ao SIG como eficaz ferramenta que possibilita mapear áreas com susceptibilidade a inundação em caso de rompimento. O HEC-RAS surge como poderoso modelo hidrológico capaz de efetuar o modelo para rompimento de barragem em integração com o Sistema de Informação Geográfica. E para classificar o grau de risco da população a jusante é fundamental a adoção de metodologia que contemple as variáveis inerentes à importância deste empreendimento, por tanto será utilizado à metodologia de Menescal (2001) por abarcar todas as facetas importantes de segurança de barragem. / Dams can be considering as a potential risk, knowledge of probable way to behave a flood wave (critical flow) caused by dam break is very important for people living on the bus downstream, as in São José do Jacuípe. This is because in case of breakage becomes necessary to have the evacuation plan for the downstream affected area. In this sense there is the use of environmental models combined with GIS as an effective tool that makes it possible to map areas with susceptibility to flooding in the event of disruption. The HEC-RAS comes as powerful hydrological model able to make the model for dam breaking in integration with Geographic Information System. And to classify the degree of risk of downstream population is essential to adopt methodology that considers the variables inherent importance of this project for both will be used to Menescal methodology (2001) to cover all the important facets of dam safety.
140

Avaliação da influência do regime de fluxo no comportamento geotécnico de uma barragem de rejeito alteada pelo método de montante. / Evaluation of the flow scheme influence in the geotechnical behavior of a tailing dam heightened through the upstream method.

João Paulo de Sousa Silva 20 October 2014 (has links)
A presente pesquisa faz uma avaliação da influenciado regime de fluxo na estabilidade de uma barragem construída pela disposição hidráulica de rejeitos. Usualmente, essas estruturas são avaliadas com modelos de equilíbrio limite adotando-se, de modo simplificado, uma superfície freática em um regime hidrostático. No entanto, em casos em que a condutividade hidráulica da fundação ou de camadas na base do aterro é relevante em relação à dos rejeitos, o fluxo se torna verticalizado e o gradiente significativo, portanto, a premissa de regime hidrostático se torna não válida. Com o objetivo de avaliar a influência desses fatores, foram realizadas análises numéricas, simulando condições de fluxo e seus reflexos nos fatores de segurança. Ademais, foi desenvolvida uma extensa análise de dados e cálculos no estudo de caso de uma barragem, com expectativa de ampliar a vida útil de uma Planta de beneficiamento de minério de ferro. Ao se incorporar a real distribuição de pressões neutras, medidas na barragem, concluiu-se que o seu Fator de Segurança era cerca de 20% maior do que o obtido em cálculos simplificados, que desconsideram o regime de fluxo descendente, admitido, por hipótese, na barragem em estudo. Alguns comentários quanto à segurança à liquefação foram feitos, exceto a liquefação dinâmica, que foge do escopo desse trabalho. / The present research evaluates the influence of the foundations permeability in the scheme of flow and in the stability of a dam built through the hydraulic tailings disposal. Usually, these structures are evaluated with models of equilibrium limit, considering, in a simplified way, a phreatic surface in a hydrostatic scheme. However, in cases in which the foundations hydraulic conductivity is relevant when related to the tailings, the flow becomes verticalized and the gradient becomes significant. Therefore, the hydrostatic scheme premise becomes not valid. With the purpose of evaluating the influence of these factors, numerical analysis were made, simulating flow conditions and their influence in the factor of safety. Moreover, an extensive data and calculations analysis was developed in the case study of a dam, with the expectation of increasing the lifetime of an ore mining beneficiation plan. When incorporating the actual distribution of porepressure, measured at the dam, it was concluded that the safety factor of the dam was about 20% higher than that obtained for simplified calculations, that disregard the downward flow regime, admitted in the dam under study. Some comments about the safety of liquefaction were made, except the dynamic liquefaction, beyond the scope of this work.

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