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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.
161

Numerical investigation of load transfer mechanisms in slopes reinforced with piles

Ang, Eng-Chew, January 2005 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2005. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (November 7, 2006) Vita. Includes bibliographical references.
162

Regulatory mechanisms in the chondrogenesis of mesenchymal progenitors the roles of cyclic tensile loading and cell-matrix interactions /

Connelly, John Thomas. January 2007 (has links)
Thesis (Ph. D.)--Mechanical Engineering, Georgia Institute of Technology, 2008. / Barbara D. Boyan, Committee Member ; Ravi Bellamkonda, Committee Member ; Joseph Le Doux, Committee Member ; Andres J. Garcia, Committee Member ; Marc E. Levenston, Committee Chair.
163

Load transfer in micropiles for slope stabilization from tests of large-scale physical models

Boeckmann, Andrew Z. January 2006 (has links)
Thesis (M.S.) University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 22, 2007) Includes bibliographical references.
164

Utilização de redes neurais recorrentes na caracterização de cargas não lineares em sistemas elétricos

Mantovani, William Amaro [UNESP] 02 December 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-02Bitstream added on 2014-06-13T19:08:06Z : No. of bitstreams: 1 mantovani_wa_me_ilha.pdf: 572859 bytes, checksum: 6f6dbbff3d2181a18b8a8a253a4fc213 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Com o surgimento de novas tecnologias, a eletrônica de potência passou a ser utilizada cada vez mais, resultando no aumento das cargas não-lineares e na adoção de dispositivos que provocam distorções harmônicas na rede elétrica. Essas distorções harmônicas geram maiores custos às empresas distribuidoras de energia elétrica, como a troca de cabos e redimensionamento de transformadores, que podem sofrer superaquecimento ou sobrecarga. Estes fenômenos prejudicam o fornecimento de energia e podem gerar futuras taxações a estas empresas, uma vez que já existe a discussão de normas que limitam o nível de distorções harmônicas presentes nos sistemas de distribuição. Uma vez constatada uma violação dos limites estabelecidos, torna-se necessária a adoção de uma sistemática para mitigação dos efeitos resultantes, que na maioria dos casos está relacionada a instalação de filtros harmônicos, sejam de natureza passiva, ativa ou híbridos. Por outro lado, em decorrência desta medida, surge naturalmente a questão vinculada a responsabilidade financeira sobre os investimentos relacionados com os procedimentos de mitigação a serem implementados. Para a realização do compartilhamento de responsabilidades, é necessário determinar a parcela de distorção harmônica total relativa somente à não-linearidade da carga. Até a presente dissertação, a única forma de se obter tal valor era desacoplando a carga do sistema e alimentando-a com uma tensão senoidal, tornando-se um processo difícil e até inviável. A proposta deste trabalho é a utilização de redes neurais recorrentes na determinação da característica não-linear da carga através da medida da tensão no PAC e da corrente no ramo da carga em questão. A partir de um processo de treinamento, a rede neural simula a admitância da carga através... / With the advent of new technologies, the power electronics has become increasingly used, resulting in increased non-linear loads and the adoption of devices that cause harmonic distortion on the grid. These harmonic distortions generate higher costs for electricity distribution companies, such as replacing cables and transformer sizing, which can overheat or overload. These problems affect the power supply and can create future taxation of these companies. There is already discussion of rules limiting the level of harmonic distortion present in distribution systems. When is found a violation of limits, becomes necessary to adopt a systematic approach to mitigating the effects arising, which in most cases is related to installation of harmonic filters, are such as passive, active or hybrid. On the other hand, as a result of this action, the question naturally arises linked to financial liability on investments related to the mitigation procedures to be implemented. For the realization of shared responsibility, is necessary to determine the share of total harmonic distortion relative just to the non-linearity of the load. Until the present work, the only way to obtain that value was decoupling the system load and feeding it with a sinusoidal voltage, making it a difficult process and even infeasible. The purpose of this work is the use of recurrent neural networks in determining the non-linear characteristic of the load by measuring the voltage at the PCC and the current in branch of the load in question. From a training process, the neural network simulates the admittance of the load by adjusting their weights. Then these weights are transferred to a second neural network simulation, which when applied to enter a purely sinusoidal voltage, a current referring just to non-linear characteristic of the load is obtained
165

Utilização de redes neurais recorrentes na caracterização de cargas não lineares em sistemas elétricos /

Mantovani, William Amaro. January 2011 (has links)
Orientador: Luiz Fernando Bovolato / Banca: Luís Carlos Origa de Oliveira / Banca: Olivio Carlos Nascimento Souto / Resumo: Com o surgimento de novas tecnologias, a eletrônica de potência passou a ser utilizada cada vez mais, resultando no aumento das cargas não-lineares e na adoção de dispositivos que provocam distorções harmônicas na rede elétrica. Essas distorções harmônicas geram maiores custos às empresas distribuidoras de energia elétrica, como a troca de cabos e redimensionamento de transformadores, que podem sofrer superaquecimento ou sobrecarga. Estes fenômenos prejudicam o fornecimento de energia e podem gerar futuras taxações a estas empresas, uma vez que já existe a discussão de normas que limitam o nível de distorções harmônicas presentes nos sistemas de distribuição. Uma vez constatada uma violação dos limites estabelecidos, torna-se necessária a adoção de uma sistemática para mitigação dos efeitos resultantes, que na maioria dos casos está relacionada a instalação de filtros harmônicos, sejam de natureza passiva, ativa ou híbridos. Por outro lado, em decorrência desta medida, surge naturalmente a questão vinculada a responsabilidade financeira sobre os investimentos relacionados com os procedimentos de mitigação a serem implementados. Para a realização do compartilhamento de responsabilidades, é necessário determinar a parcela de distorção harmônica total relativa somente à não-linearidade da carga. Até a presente dissertação, a única forma de se obter tal valor era desacoplando a carga do sistema e alimentando-a com uma tensão senoidal, tornando-se um processo difícil e até inviável. A proposta deste trabalho é a utilização de redes neurais recorrentes na determinação da característica não-linear da carga através da medida da tensão no PAC e da corrente no ramo da carga em questão. A partir de um processo de treinamento, a rede neural simula a admitância da carga através... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: With the advent of new technologies, the power electronics has become increasingly used, resulting in increased non-linear loads and the adoption of devices that cause harmonic distortion on the grid. These harmonic distortions generate higher costs for electricity distribution companies, such as replacing cables and transformer sizing, which can overheat or overload. These problems affect the power supply and can create future taxation of these companies. There is already discussion of rules limiting the level of harmonic distortion present in distribution systems. When is found a violation of limits, becomes necessary to adopt a systematic approach to mitigating the effects arising, which in most cases is related to installation of harmonic filters, are such as passive, active or hybrid. On the other hand, as a result of this action, the question naturally arises linked to financial liability on investments related to the mitigation procedures to be implemented. For the realization of shared responsibility, is necessary to determine the share of total harmonic distortion relative just to the non-linearity of the load. Until the present work, the only way to obtain that value was decoupling the system load and feeding it with a sinusoidal voltage, making it a difficult process and even infeasible. The purpose of this work is the use of recurrent neural networks in determining the non-linear characteristic of the load by measuring the voltage at the PCC and the current in branch of the load in question. From a training process, the neural network simulates the admittance of the load by adjusting their weights. Then these weights are transferred to a second neural network simulation, which when applied to enter a purely sinusoidal voltage, a current referring just to non-linear characteristic of the load is obtained / Mestre
166

Wind Load Analysis on a High-rise Square-plan Building

January 2014 (has links)
abstract: Buildings and other structures, all components and cladding thereof, shall be designed and constructed to resist the wind loads are required in all wind codes. Simple quasi-static treatment of wind loads, which is universally applied to design of low to medium-rise structures, can be either overly conservative or erroneous under-estimated for design of high-rise structures. Dynamic response, vortex, wind directionality, and shedding from other structures are all complicated key factors suppose to be considered in design. Meanwhile, wind tunnel testing is expansive, difficult and sometimes inaccurate even if it is a widely used method in simulation of aerodynamic response. Computational Fluid dynamics (CFD), historically, were two-dimensional (2D) method using conformal transformations of the flow about a cylinder to the flow about an airfoil were developed in the 1930s. A number of three-dimensional (3D) codes were developed, leading to numerous commercial packages, which is more accessible and economical for wind load analysis. / Dissertation/Thesis / Masters Thesis Civil and Environmental Engineering 2014
167

The Impact of Training Loads on In-Match Soccer Performance Variables: A Position-Based Case Report

Bingham, Garett 01 August 2015 (has links)
It is critical to maintain multiple fitness characteristics during the soccer season through the use of training, but also to ensure that the training loads do not hinder subsequent match performance. The purpose of this thesis is to investigate the impact of the training load on key physical performance variables in the subsequent match. Five Division I female soccer players were analyzed across six weeks of training and matches. Training loads in the forms of odometer, high intensity odometer, estimated odometer and sRPE were accumulated at time points from one to five days prior to a match. The accumulated training loads were then correlated with the same performance measures from match play. The greatest significant correlations were seen in sRPE training loads when compared to match odometer and estimated distance. There does not appear to be negative effect on match performance when looking at any of the accumulated training load values.
168

Compacting Loads and Stores for Code Size Reduction

Asay, Isaac 01 March 2014 (has links)
It is important for compilers to generate executable code that is as small as possible, particularly when generating code for embedded systems. One method of reducing code size is to use instruction set architectures (ISAs) that support combining multiple operations into single operations. The ARM ISA allows for combining multiple memory operations to contiguous memory addresses into a single operation. The LLVM compiler contains a specific memory optimization to perform this combining of memory operations, called ARMLoadStoreOpt. This optimization, however, relies on another optimization (ARMPreAllocLoadStoreOpt) to move eligible memory operations into proximity in order to perform properly. This mover optimization occurs before register allocation, while ARMLoadStoreOpt occurs after register allocation. This thesis implements a similar mover optimization (called MagnetPass) after register allocation is performed, and compares this implementation with the existing optimization. While in most cases the two optimizations provide comparable results, our implementation in its current state requires some improvements before it will be a viable alternative to the existing optimization. Specifically, the algorithm will need to be modified to reduce computational complexity, and our implementation will need to take care not to interfere with other LLVM optimizations.
169

Určení aerodynamických charakteristik VOP letounu CFD metodou / Determination of Aerodynamic Characteristics of Horizontal Tail using CFD Methods

Šrůtek, Michal January 2008 (has links)
The diploma thesis describes computation empennage maneuvering flight loads in CFD code Fluent V6 and comparison with computational code AVL.
170

Mechanical Splices for Seismic Retrofitting of Concrete Structures

Huaco, G., Huaco, G., Jirsa, J. 07 February 2020 (has links)
As an alternative to lap splicing, mechanical splices can be used for retrofit purposes. They are generally most economical than traditional lap splices when available spacing or length makes laps difficult to utilize. Mechanical splices are frequently used in new construction. However, their use is limited and not practical for use in retrofitted structures. However, if the bars to be joined do not need to be threaded in order to be connected with a special mechanical splice, such mechanical splices can be useful. It is presented a proposal of using two types of mechanical splices for retrofit purposes. Cycle Tension and cycle tension-compression tests are presented and discussed. It was found that mechanical splices are suitable and have acceptable response under seismic loads.

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