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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.
21

Integration of Advanced Optics for Trapped Ion Quantum Information Processing

Noek, Rachel January 2013 (has links)
<p>Trapped ion systems are the leading candidate for quantum information processing because many of the critical components have already been demonstrated. Scaling trapped ion systems to large numbers of ions is currently believed possible, but much work remains to prove it. Microfabricated surface ion traps are increasing in popularity for their ease of mass production and their ability to manipulate individual ions and interact arbitrary pairs of ions. Even with the advent of scalable ion traps, detection of an individual ion trapped in a high vacuum poses a challenge. The internal state of the ion chosen for a quantum bit can be measured via exposure to a probe beam that causes one state to scatter light (a "bright" state), but not the other state (a "dark" state). In free space, a single ion acts like a point source that emits in all directions; a standard two inch lens system can only collect about 2% of the light emitted by the ion. Poor light collection results in a high error rate and slow determination of the internal state of the ion. Fast, high fidelity state detection is necessary for quantum error correction and loophole-free Bell experiments at short (less than 100\,km) distances, and high efficiency collection is necessary to rapidly interconnect separate quantum computers. We demonstrate state detection fidelities of 99%, 99.856(8)% and 99.915(7) % which correspond to detection times of 10.5, 28.1 and 99.8 us, respectively.</p> / Dissertation
22

Caracterização ambiental e estimativa da produção de cargas difusas da área de drenagem da represa de Itupararanga, SP / Environmental characterization and estimative of diffuse pollution of Itupararanga watershed, SP

Lorena Ferrari Secchin 24 May 2012 (has links)
O uso de imagens de satélite tem aprimorado o estudo da dinâmica do uso do solo. Os mapeamentos da cobertura da terra se tornaram instrumentos fundamentais na avaliação das alterações na paisagem provocadas pela ação antrópica e sua influência sobre o planejamento regional e urbano. A utilização de ferramentas computacionais como os Sistemas de Informação Geográfica e os modelos hidrológicos têm auxiliado essas avaliações. O modelo hidrológico SWAT (Soil and Water Assessment Tool), desenvolvido pelo Departamento de Agricultura norte-americano, é um modelo de base física e parâmetros distribuídos, auxiliado por uma interface gráfica de software GIS. Por seu valor ambiental e econômico, a caracterização ambiental da área de drenagem da Represa de Itupararanga, com 936,54 \'KM POT.2\', localizada no estado de São Paulo, tem fundamental importância e a utilização de dados atuais permite que o estudo da área seja mais preciso no que diz respeito aos seus resultados. A partir de imagens do sensor Liss 3 do satélite ResourceSat-1, foi produzido o mapa atual de uso e ocupação do solo através da classificação supervisionada de máxima verossimilhança, validada por coletas de campo de ponto de controle com índice Kappa de 0,64 e índice de exatidão global de 71%. Os parâmetros morfológicos demonstraram que a área de estudo é bem drenada e possui baixa probabilidade de enchentes. A modelagem hidrológica foi calibrada para o período de janeiro de 2005 a dezembro de 2008 e resultou em coeficiente de eficiência de 0,41 e tendência percentual de 0%. A validação alcançou resultado de 0,301 e 5,5% para estes avaliadores, valores de ajuste considerados aceitáveis. Foram encontrados os valores de 9,66 e 1,5 para nitrogênio e fósforo, respectivamente, em kg/ha.ano, para os valores de poluição difusa, resultados elevados na comparação entre pesquisas com este foco. A comparação entre cenários identificou a necessidade de adotar práticas conservacionistas através do planejamento da ocupação para tornar sustentáveis as atividades dentro bacia e atenuar as pressões sobre os recursos naturais. / The use of satellite images has improved the study of the land use dynamics. Land cover mapping have become fundamental tools in the assessment of landscape changes caused by human action and its influence on regional and urban planning. Computation tools such as Geographic Information Systems and hydrological models have supported these findings. The hydrological model SWAT (Soil and Water Assessment Tool), developed by U. S. Agriculture Department, a model physically based and semi-distributed parameters with a GIS graphical interface. Due your environmental and economic value, the morphologic characterization of Itupararanga watershed, with 936,54 \'KM POT.2\', located in São Paulo state, have fundamental relevance and use of current data alows the study be more accurate. From images of Liss 3 sensor of ResourceSat-1 satelite, the current land use map was produced through supervised classification by maximum likelihood method and validated by control points on field collection, resulting in Kappa coefficient of 0.64 and overall accuracy rate of 71%. The morphological parameters showed that watershed is well drained and has low probability of flooding. The hydrological modeling was calibrated from January of 2005 to December of 2008 and had efficient value of 0.41 and trend rate of zero. Validation reached results of de 0.301 and 5.5% for these coefficients, considered acceptable for adjust values. Were found values of 9.66 and 1.5 for nitrogen and phosphorus, in kg/ha.year, respectively, for the values of diffuse pollution, high results in comparison between studies with this focus. The comparison between scenarios indentified the need to adopt conservation pratices through occupation planning to make the activities inside the basin and mitigate the pressure on natural resources.
23

Application of SWAT and Development of a Water Quality Predictive Model for Water Resources Management in Rural Basins / 農村流域における水資源管理のためのSWATの適用と水質予測モデルの開発

BAOBAB, KIBET KIMENGICH 23 September 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第22785号 / 農博第2428号 / 新制||農||1081(附属図書館) / 学位論文||R2||N5305(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 藤原 正幸, 教授 村上 章, 教授 中村 公人 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
24

HYDROGRAPH-SEPARATION-BASED NON-POINT SOURCE POLLUTION MODELLING IN THE PINGQIAO RIVER BASIN,CHINA / 中国平橋川流域を対象にした流出ハイドログラフ成分分離法による非点源汚染モデリングの研究

Xue, Han 23 March 2017 (has links)
付記する学位プログラム名: グローバル生存学大学院連携プログラム / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20341号 / 工博第4278号 / 新制||工||1662(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 寶 馨, 教授 立川 康人, 准教授 佐山 敬洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
25

Evaluation of Rapidly Growing Vegetation on Mississippi Roadsides

Bradford, Timothy, Jr. 17 August 2013 (has links)
Non-point source pollution caused by erosion from road construction poses hazardous environmental effects. Percolation and infiltration of nutrients into groundwater can also be detrimental to the surrounding environment. In addition, annual roadside maintenance budget exceeded $14 million in 2011 for Mississippi. Objectives of this research were to evaluate rapidly established short-statured species in an effort to prevent erosion, combat non-point source pollution, reduce mowing cost, and provide quick cover following propagation. Factors evaluated were rate of establishment, plant cover, and mowing requirement. MDOT’s standard seed mix was evaluated along with Pennington’s SlopeMaster product and different combinations of selected plant species. Visual and image analysis showed oilseed radish plants established the quickest and provided the most cover. All sod treatments provided instant cover while Pennington’s Slopemaster product, as well as mixes that contained bermudagrass or bahiagrass, provided sufficient cover, but not in a timely manner.
26

Isar Target Reconstruction Via Dipole Modeling

Nassib, Ali Hussein 18 May 2016 (has links)
No description available.
27

Analysis of Non-point Sources and Natural Attenuation Effect in the Acid Mine Drainage Affected Black Fork Sub-watershed, Perry County, Ohio

Bradley, Xuan Qi 02 December 2002 (has links)
No description available.
28

The Efficiency of Vegetated Biofilters to Mitigate Highway Stormwater Runoff and the Fate of these Contaminants within the Bed

Armeni, Lauren E. 20 July 2010 (has links)
No description available.
29

Two Cost Analyses in Resource Economics: The Public Service Costs of Alternative Land Settlement Patterns and Effluent Allowance Trading in Long Island Sound

Speir, Cameron Lindsey 08 February 2000 (has links)
This study offers two cost analyses to inform public policy decisions on the use of land and water resources. The first presents some public service costs associated with different spatial forms of land development. The second cost analysis presents costs associated with three different policy options for meeting water quality goals in Long Island Sound. The objective the first analysis is to determine the cost to local governments of providing water distribution and wastewater collection services to alternative spatial forms of residential development. Components of spatial form are explicitly defined in terms of lot size, distance and tract dispersion. An engineering cost model is used to determine the water and sewer costs to three sets of hypothetical land settlement scenarios. Each set shows the effect of one component of spatial form on cost. The results show that smaller lots, shorter distances between existing centers and less tract dispersion reduce public water and sewer costs. Lot size is found to have the most pronounced effect on water and sewer cost. Some policy options for reducing the public service costs associated with development are considered. The objective of the second cost analysis is to analyze the cost implications of a nitrogen allowance trading system for wastewater treatment plants in Connecticut. Effluent allowance trading involves the transfer of pollution control responsibility between pollution sources. Effluent allowances are the right to discharge a given quantity of waste into the environment over a given time period. Allowance trading has been proposed as a way of reducing pollution control costs, encouraging innovative pollution prevention techniques and more quickly achieving water quality goals. Long Island Sound, a major estuary in the northeastern United States, experiences chronically low dissolved oxygen levels. Excessive nitrogen loads from anthropogenic activities in the Sound watershed have been identified as the cause of the oxygen problem. The state of Connecticut is examining the possibility of introducing an effluent allowance trading system in order to reduce the cost of achieving required reductions in nitrogen discharge. A linear programming model is used to predict trading outcomes and allowance prices. The total cost of achieving a nitrogen load cap is calculated under three administrative approaches. The first approach is a uniform reduction requirement where all plants are required to reduce discharge by the same proportion. The second approach is an administrative reallocation of waste load where a regulatory agency assigns control responsibility based on the agency's understanding of relative costs. The third approach is a flexible effluent allowance trading system. The results will show that a trading program offers cost savings over traditional regulatory approaches, demonstrate the potential for further cost savings from pollution prevention activities and estimate the cost savings that would result from including nonpoint sources in the overall nitrogen reduction strategy. / Master of Science
30

Essays on Water Policy and Coupled Human and Natural Systems

Weng, Weizhe 02 August 2019 (has links)
Human and freshwater ecosystems are intrinsically interconnected. To better design effective policies, modeling tools and valuation methods are necessary to help understanding the complex reciprocal linkages between ecosystem processes and human actions, and coupled human and natural systems (CNHS) sets up a critical paradigm to do so. It is thus of both academic and empirical appeal to integrate reliable economic valuation methods with tools and models from multiple disciplines in order to quantify the feedbacks between human and natural systems and to inform better policy design. Using freshwater resources as an example, this dissertation contains three essays which integrate natural science and economics models to understand how changes in human behavior and societal policies lead to changes in ecosystem services, and how changes in ecosystem services, in return, affect human decisions. The first two essays focus on agricultural nonpoint source pollution problems in United States and examines the impacts of potential water polices on both water polluters and water demanders. Specifically, in the first essay, a novel coupling between an ecological model of within-lake hydrodynamics and an economic model of hedonic property prices has been developed to quantify the connections between nutrient loading, lake water quality, and economic outcomes. Linking ecological processes with human decision-making provides a basis for enhanced evidence-based decision making in the context of reducing nonpoint-source pollution. In the second essay, an economic mathematical programming model is coupled with an agro-ecosystem model to investigate the behavioral adjustments and environmental pollution outcomes of water quality policies. A complete quantification of costs from all regulating sources are necessary to help pinpoint the efficient water policy design and reflecting the connection between human decisions and ecosystem processes. The third essay focus on the water quantity problem in another developed country, Australia. A discrete choice experiment method has been explored and used to provide estimates of willingness to pay for purchasing irrigation rights to restore a Ramsar-convention wetland. Water policy scenario described in this essay could directly affect the feedback between human and ecosystem processes and serve as a baseline for future planning and policy designs. By offering both conceptual and methodological advancements, this dissertation aims to improve the understanding of coupled human and natural systems and the implementation of water policies. This dissertation also provides a framework to establish multi-disciplinary dialogues and cooperation between scientists and economists in the search of efficient water polices. / Doctor of Philosophy / Freshwater resources are one of the most important elements in our daily life. It provides important goods and services to our society, but at the same time, due to human behaviors, freshwater resources are under threat in both their quality and quantity. This dissertation contains three essays which integrate knowledge from multiple disciplines to help understand and quantify the linkages between human and freshwater resources, and provides information to come up with better water polices. In the first essay, I explore the connections between nutrient loading, lake water quality, and the economic outcomes. The essay illustrates how potential change in nutrient loadings affect lake water quality, and how that induces people’s housing purchase behavior, property sales price and local governments’ property tax revenue. In the second essay, I focus on the agricultural production problem, which is one of the largest source for water quality degradation. By exploring the impacts of water policy on farmers’ production decisions, the essay sheds light on how to better design water polices to maintain farmers’ profit while simultaneously alleviating the impact of agricultural production to water qualities. In the third essay, I utilize a survey method, choice experiments, to elicit people’s willingness to pay for wetland ecosystem health. This could better allocate water resources between agricultural production use and residential use and come up with better water quantity polices.

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