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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.
421

Robustness of normal theory inference when random effects are not normally distributed

Devamitta Perera, Muditha Virangika January 1900 (has links)
Master of Science / Department of Statistics / Paul I. Nelson / The variance of a response in a one-way random effects model can be expressed as the sum of the variability among and within treatment levels. Conventional methods of statistical analysis for these models are based on the assumption of normality of both sources of variation. Since this assumption is not always satisfied and can be difficult to check, it is important to explore the performance of normal based inference when normality does not hold. This report uses simulation to explore and assess the robustness of the F-test for the presence of an among treatment variance component and the normal theory confidence interval for the intra-class correlation coefficient under several non-normal distributions. It was found that the power function of the F-test is robust for moderately heavy-tailed random error distributions. But, for very heavy tailed random error distributions, power is relatively low, even for a large number of treatments. Coverage rates of the confidence interval for the intra-class correlation coefficient are far from nominal for very heavy tailed, non-normal random effect distributions.
422

A toolbox for multi-objective optimisation of low carbon powertrain topologies

Mohan, Ganesh 05 1900 (has links)
Stricter regulations and evolving environmental concerns have been exerting ever-increasing pressure on the automotive industry to produce low carbon vehicles that reduce emissions. As a result, increasing numbers of alternative powertrain architectures have been released into the marketplace to address this need. However, with a myriad of possible alternative powertrain configurations, which is the most appropriate type for a given vehicle class and duty cycle? To that end, comparative analyses of powertrain configurations have been widely carried out in literature; though such analyses only considered limited types of powertrain architectures at a time. Collating the results from these literature often produced findings that were discontinuous, which made it difficult for drawing conclusions when comparing multiple types of powertrains. The aim of this research is to propose a novel methodology that can be used by practitioners to improve the methods for comparative analyses of different types of powertrain architectures. Contrary to what has been done so far, the proposed methodology combines an optimisation algorithm with a Modular Powertrain Structure that facilitates the simultaneous approach to optimising multiple types of powertrain architectures. The contribution to science is two-folds; presenting a methodology to simultaneously select a powertrain architecture and optimise its component sizes for a given cost function, and demonstrating the use of multi-objective optimisation for identifying trade-offs between cost functions by powertrain architecture selection. Based on the results, the sizing of the powertrain components were influenced by the power and energy requirements of the drivecycle, whereas the powertrain architecture selection was mainly driven by the autonomy range requirements, vehicle mass constraints, CO2 emissions, and powertrain costs. For multi-objective optimisation, the creation of a 3-dimentional Pareto front showed multiple solution points for the different powertrain architectures, which was inherent from the ability of the methodology to concurrently evaluate those architectures. A diverging trend was observed on this front with the increase in the autonomy range, driven primarily by variation in powertrain cost per kilometre. Additionally, there appeared to be a trade-off in terms of electric powertrain sizing between CO2 emissions and lowest mass. This was more evident at lower autonomy ranges, where the battery efficiency was a deciding factor for CO2 emissions. The results have demonstrated the contribution of the proposed methodology in the area of multi-objective powertrain architecture optimisation, thus addressing the aims of this research.
423

Private Water Well Components

Farrell-Poe, Kitt, Jones-McLean, Lisa, McLean, Scott 04 1900 (has links)
4 pp. / 1. Drinking Water Wells; 2. Private Water Well Components; 3. Do Deeper Wells Mean Better Water; 4. Maintaining Your Private Well Water System; 5. Private Well Protection; 6. Well Water Testing and Understanding the Results; 7. Obtaining a Water Sample for Bacterial Analysis; 8. Microorganisms in Private Water Wells; 9. Lead in Private Water Wells; 10. Nitrate in Private Water Wells; 11.Arsenic in Private Water Wells; 12. Matching Drinking Water Quality Problems to Treatment Methods; 13. Commonly Available Home Water Treatment Systems; 14. Hard Water: To Soften or Not to Soften; 15. Shock Chlorination of Private Water Wells / This fact sheet is one in a series of fifteen for private water well owners. The one- to four-page fact sheets will be assembled into a two-pocket folder entitled Private Well Owners Guide. The titles will also be a part of the Changing Rural Landscapes project whose goal is to educate exurban, small acreage residents. The authors have made every effort to align the fact sheets with the proposed Arizona Cooperative Extension booklet An Arizona Well Owners Guide to Water Sources, Quality, Sources, Testing, Treatment, and Well Maintenance by Artiola and Uhlman. The private well owner project was funded by both the University of Arizonas Water Sustainability Program-Technology and Research Initiative Fund and the USDA-CSREES Region 9 Water Quality Program.
424

Cross-polar coupling in GTEM cells used for radiated emission measurements

Nothofer, Angela January 2000 (has links)
No description available.
425

INVESTIGATION OF TECHNIQUES FOR FABRICATING PLASTIC OPTICAL COMPONENTS

Blecher, Stephen 08 1900 (has links)
QC 351 A7 no. 77 / Because of their light weight and low cost, transparent plastics would seem to be good materials for optical components. This thesis deals primarily with the feasibility of producing large ( >4 -in. -diam) plastic components of moderate precision (surface accuracies 1 fringe per inch of diameter). The structure and the physical and optical properties of plastics are discussed, with emphasis on their advantages and limitations for optical use. A series of experiments on grinding and polishing of plastics was conducted. Data are presented on grinding rates. Several polishing processes were evaluated, and a polishing technique for plastics was developed. Polishing rate data and surface roughness data are presented for several polishing processes. With proper techniques, we estimate that accuracies of about one fringe per inch are obtainable. A series of experiments was conducted on a process called compression forming, in which heat and pressure are applied to machined preforms in an attempt to obtain precision optical surfaces. The process is described in detail, and experimental results are discussed. Based on experimental results, improved processing conditions are suggested. Further experiments would be required to determine the ultimate process capability.
426

Cloud computing using a hierarchical component system / Cloud computing using a hierarchical component system

Kučera, Tomáš January 2011 (has links)
Cloud computing is nowadays a popular computing paradigm. Computers are interconnected via network and jointly offer a lot of computing performance. SOFA 2 is a hierarchical component system offering a distributed run-time environment; therefore, it is a suitable environment for cloud computing. Applications are composed from components; each component may run on different computer in the `cloud'. The deployment of the components influences the overall performance of the application and the utilization of resources in the `cloud'; therefore, it has to be planned carefully. In this thesis, an algorithm for automated deployment planning of hierarchical component-based applications is proposed and further implemented in the SOFA 2 system. The algorithm incorporates components' demands and machines' resources in order to maximize performance of the deployed applications. The thesis also proposes and implements extensions that allow using the SOFA 2 component system as an actual cloud platform.
427

Kondiční příprava florbalového brankáře / Floorball goalkeeper conditioning

Koráb, Jakub January 2012 (has links)
The title of the work: Floorball goalkeeper conditioning The aim of the work: Based on the identified needs for floorball goalkeeper conditioning the diploma thesis deals with composing the manual for stimulating their specific demands. Methodology: The essentials of the work are both foreign and Czech literature searches dealing with the given issue, measuring functional ability with a sporttester and maximum heart rate laboratory measurement. Based on floorball goalkeeping functional requirements two main areas of stimulation have been defined - speed and speed endurance. The work has been consulted with the renowned conditioning trainers - namely e.g. Josef Bruk (ice hockey goaltending), PhDr. Aleš Kaplan (basketball, football, athletics) and PaeDr. Miroslav Špalek (football goalkeeping, tennis). Outcomes: Measured values of heart rate during floorball goalkeeping performance have reached over 70 % of goalkeepers' maximum heart rate. The measured data show high demands on conditioning component of floorball goalkeeping and the need for its continuous improvement for better performance. As with growing heart rate combine some negative impacts on performance - tiredness and concentration problems. It is possible to influence versatile fitness, adapt organism to physical load and develop specific...
428

Subspace Tracking, Discrimination of Unexploded Ordinances (UXO) in Airborne Magnetic Field Gradients

Jeoffreys, Mark 28 February 2007 (has links)
Student Number : 9807515F - MSc Dissertation - School of Computational and Applied Mathematics - Faculty of Science / Statistical and algebraic techniques of subspace tracking were tested for filtering the earth’s response from airborne magnetic field gradients in order to discriminate the relatively small response (dipole) of objects on the earth’s surface, such as UXO. Filtering the data was not very effective with these methods but a subspace was found in the data for the magnitude of the magnetic moment of the dipole. This subspace is easily obtained using the singular value decomposition and can be used for an approximate location, without depth estimation, as well as the relative size of the dipole.
429

Ambiente integrado para verificação e teste da coordenação de componentes tolerantes a falhas / An integrated environment for verification and test of fault-tolerant components coordination

Hanazumi, Simone 01 September 2010 (has links)
Hoje, diante das contínuas mudanças e do mercado competitivo, as empresas e organizações têm sempre a necessidade de adaptar suas práticas de negócios para atender às diferentes exigências de seus clientes e manter-se em vantagem com relação às suas concorrentes. Para ajudá-las a atingir esta meta, uma proposta promissora é o Desenvolvimento Baseado em Componentes (DBC), cuja ideia básica é a de que um novo software possa ser construído rapidamente a partir de componentes pré-existentes. Entretanto, a montagem de sistemas corporativos mais confiáveis e tolerantes a falhas a partir da integração de componentes tem-se mostrado uma tarefa relativamente complexa. E a necessidade de garantir que tal integração não falhe tornou-se algo imprescindível, sobretudo porque as consequências de uma falha podem ser extremamente graves. Para que haja uma certa garantia de que o software seja tolerante a falhas, devem ser realizadas atividades de testes e verificação formal de programas. Isto porque ambas, em conjunto, procuram garantir ao desenvolvedor que o sistema resultante da integração é, de fato, confiável. Mas a viabilidade prática de execução destas atividades depende de ferramentas que auxiliem sua realização, uma vez que a execução de ambas constitui um alto custo para o desenvolvimento do software. Tendo em vista esta necessidade de facilitar a realização de testes e verificação nos sistemas baseados em componentes (DBC), este trabalho de Mestrado se propõe a desenvolver um ambiente integrado para a verificação e teste de protocolos para a coordenação do comportamento excepcional de componentes. / Nowadays, because of continuous changes and the competitive market, companies and organizations have the necessity to adapt their business practices in order to satisfy the different requirements of their customers and then, keep themselves in advantage among their competitors. To help them to reach this aim, a promising purpose is the Component-Based Development (CBD), whose basic idea is that a new software can be built in a fast way from preexisting components. However, mounting more reliable and fault-tolerant corporative systems from components integration is a relatively complex task. And the need to assure that such integration does not fail becomes something essential, especially because the consequences of a failure can be extremely serious. To have a certain guarantee that the software will be fault-tolerant, testing activities and formal verification of programs should be done. This is because both, together, try to assure to developer that the resulting system of the integration is, in fact, reliable. But the practical feasibility of executing these activities depends on tools which support it, once both executions have a high cost to software development. Having the necessity to make test and verification easier in systems based in components (CBD), this work has, as main objective, the development of an integrated environment for verification and test of protocols to the coordination of components exceptional behaviour.
430

Caracterização das áreas queimadas no estado do Tocantins no ano de 2014

Neves, Cínthia Ohana Marques 17 June 2016 (has links)
Neste estudo, objetivou-se caracterizar áreas queimadas em todo o Estado do Tocantins, durante o ano de 2014, por meio de análise exploratória e de componentes principais. Esta última foi empregada para estabelecer a relação das áreas queimadas com dados territoriais e socioeconômicos dos municípios tocantinenses. Por meio da análise do histórico de focos de calor no Estado, foram utilizadas imagens de satélite referentes aos meses de julho a outubro, período crítico de ocorrência. Foram utilizadas imagens TM do satélite Landsat-8, por meio do download das bandas referentes ao visível: infravermelho médio (1,57–1,65 μm), infravermelho próximo (0,85–0,88 μm) e vermelho (0,64-0,67 μm), na composição de bandas 6R5G4B (Red –vermelho, Green-verde, Blue-azul), com resolução espacial de 30 metros e resolução temporal de 16 dias. Foi realizado o processamento e interpretação visual das imagens, com a vetorização (digitalização) das áreas queimadas e incêndios. Os dados vetoriais das áreas queimadas foram cruzados com sete base de dados (precipitação média anual, pedologia, temperatura média anual, bacia hidrográfica, declividade, unidades de conservação, e o uso da terra), disponibilizadas pela Secretaria de Planejamento e Orçamento do Tocantins, e os dados territoriais e socioeconômicos dos municípios tocantinenses. Estes últimos foram utilizados na análise de componentes principais (CP), que extraiu cinco CP que explicam 81,74% da variância dos dados. Esta análise, ainda, indicou que a cicatriz apresentou maior relação linear positiva com a área do município, quantidade de focos de calor, e áreas de pastagens naturais e florestas. Pela análise espacial, com uso da função K de Ripley e Índice Global de Moran, nos locais de maior ocorrência de queimadas (regiões do Jalapão e da Ilha do Bananal), bem como no Estado todo, a ocorrência de queimadas pôde ser considerada de padrão agregado por toda a escala. Foi possível concluir, através deste trabalho, que além das condições ambientais intrínsecas do Cerrado, municípios com maiores áreas queimadas, que estão inseridos nestas duas regiões, estiveram associados com maiores PIB da agropecuária e menores PIB de serviços e indústria e menor número de habitantes. / This study objected to characterize the burned areas in the Tocantins State, 2014 season, by the exploratory and principal component analysis. This one used for knowledge the relationship of burned area with territorial and socioeconomically data of Tocantins cities. By historical analysis of heat spots in Tocantins, they were used satellite images between July and October. They were used the following bands, of sensors of Landsat-8 satellite: shortwave infrared (1.57–1.65 μm), near infrared (0.85–0.88 μm) and red (0.64-0.67 μm), in the RGB composition, with a spatial-temporal resolution of 30 meters and 16 days. It was conducted the processing and visual interpretation of the images, for the vectorization of the burned areas. These data were crossed with seven database (annual average precipitation, pedology, annual average temperature, watershed, slope, protected area and land use), available on Secretariat of Planning and Budget of Tocantins, and with the territory and socioeconomic data of the Tocantins cities. These last data were used in principal component analysis (PCA) that were extracted five PCA (data variance explained was 81.74%). These analyses revealed that burned area had shown highest positive relationship with city area, number of heat spots, natural pasture and forest areas. By the spatial analysis, K Ripley’s function and Moran’s index, the burned area occurrence, in the Tocantins State (include regions with highest burned area, as Jalapão and Bananal island), cannot be considered aleatory. It was possible to conclude, beyond environment conditions of Cerrado, the cities with highest burned area related with high agricultural GDP and low GDP of services and industry and low population.

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