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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

Discrete gate sizing and timing-driven detailed placement for the design of digital circuits / Dimensionamento de portas discreto e posicionamento detalhado dirigido a desempenho para o projeto de circuitos digitais

Flach, Guilherme Augusto January 2015 (has links)
Ferramentas de projeto de circuitos integrados (do inglˆes, electronic design automation, ou simplesmente EDA) tˆem um papel fundamental na crescente complexidade dos projetos de circuitos digitais. Elas permitem aos projetistas criar circuitos com um n´umero de componentes ordens de grandezas maior do que seria poss´ıvel se os circuitos fossem projetados `a m˜ao como nos dias iniciais da microeletrˆonica. Neste trabalho, dois importantes problemas em EDA ser˜ao abordados: dimensionamento de portas e posicionamento detalhado dirigido a desempenho. Para dimensionamento de portas, uma nova metodologia de relaxac¸ ˜ao Lagrangiana ´e apresentada baseada em informac¸ ˜ao de temporarizac¸ ˜ao locais e propagac¸ ˜ao de sensitividades. Para posicionamento detalhado dirigido a desempenho, um conjunto de movimentos de c´elulas ´e criado usando uma formac¸ ˜ao ´otima atenta `a forc¸a de alimentac¸ ˜ao para o balanceamento de cargas. Nossos resultados experimentais mostram que tais t´ecnicas s˜ao capazes de melhorar o atual estado-da-arte. / Electronic design automation (EDA) tools play a fundamental role in the increasingly complexity of digital circuit designs. They empower designers to create circuits with several order of magnitude more components than it would be possible by designing circuits by hand as was done in the early days of microelectronics. In this work, two important EDA problems are addressed: gate sizing and timing-driven detailed placement. They are studied and new techniques developed. For gate sizing, a new Lagrangian-relaxation methodology is presented based on local timing information and sensitivity propagation. For timing-driven detailed placement, a set of cell movement methods are created using drive strength-aware optimal formulation to driver/sink load balancing. Our experimental results shows that those techniques are able to improve the current state-of-the-art.
32

Algoritmo de posicionamento analítico-detalhado guiado a caminhos críticos / Analytical detailed placement algorithm for critical paths

Monteiro, Jucemar Luis January 2014 (has links)
O posicionamento das portas lógicas tem papel fundamental na qualidade de um circuito digital. A qualidade do posicionamento impacta diretamente na tamanho do circuito, no tempo de propagação dos sinais, consumo de energia, área com problemas de aquecimento, demanda de recursos de roteamento, etc. Desse modo, algoritmos de posicionamento de portas lógicas tem sido investigado por muitas décadas em busca de soluções de posicionamento com melhor qualidade e com o menor tempo de execução possível. Além disso, o posicionamento de portas lógicas é um problema de otimização combinatorial e ele é um dos problemas pertencentes a classe NP-Difícil. Desse modo, obter a solução ótima em tempo computalcional razoável é praticamente impossível. Portanto, a investigação de técnicas e algoritmos que provenham melhores soluções do que as obtidas atualmente para o posicionamento de portas lógicas é de fundamental importância para o contínuo avanço da indústria de microeletrônica. Neste trabalho foi proposto um algoritmo de posicionamento analítico detalhado para minimizar as violações no tempo de propagação dos sinais de dados. O algoritmo proposto é uma adaptação de um algoritmo de posicionamento analítico quadrático da etapa de posicionamento global para atuar sobre as portas lógicas combinacionais dos caminhos críticos na etapa de posicionamento detalhado. As portas lógicas movimentadas pela formulação propostas são aquelas combinacionais pertencentes aos caminhos críticos e aquelas que são vizinhas no primeiro nível lógico das pertencentes aos caminhos críticos. O algoritmo proposto opera somente sobre os caminhos com violações no tempo de propagação de late dos sinais de dados. A validação experimental do algoritmo proposto mostrou que as violações de Worst Negative Slack (WNS) e Total Negative Slack (TNS) foram reduzidas, respectivamente, em até 47,9% e 59,6% no tempo de propagação dos sinais de dados. Portanto, a qualidade do posicionamento detalhado incrementa em até 5%. Por outro lado, as violações de Average Bin Utilization (ABU) incrementam em até 5,5%. O algoritmo de posicionamento analítico detalhado opera sobre no máximo 1% do total de portas lógicas dos circuitos analisados. / The logical gates placement has a fundamental impact on the placement quality of the circuit. The placement quality impacts directly on circuit size, timing propagation, power consumption, hotspot areas, etc. Therefore, placement algorithms have been researched for a long time to improve placement quality with less runtime to find a good solution to the placement problem. In this work was proposed an analytical detailed placement algorithm to minimize timing propagation violations. The proposed algorithm was adapted from a quadratic algorithm of the global placement step to handle critical paths in detailed placement step. Detailed quadratic algorithm moves gates in critical paths and the gates in the first deep logical level of the ones in critical paths that are the immediate neighbors. The detailed analytical algorithm works only in combinational gates that are part of critical paths and for ones in late critical paths. The experimental validation of the proposed detailed analytical algorithm shows a reduction in WNS and TNS violation, respectively, up to 47.9% and 59.6% in timing propagation. Therefore, detailed placement quality had improved up to 5%. Otherwise, ABU penalty also increased up to 5.5%. In our formulation is moved up to 1% of the total number of gates in the benchmarks.
33

Realizace a zaměření sítě polohových a výškových bodů podrobného polohového bodového pole v dané lokalitě / Project and surveying of the network for planimetry and height points of the detailed minor horizontal control in a chosen area

UHLÍK, Michal January 2012 (has links)
This dissertation entitled "Project and surveying of the network for planimetry and height points of the detailed minor horizontal control in a chosen area" aims to build a detailed minor horizontal control in a target area, located in the cadastral area Jenín and Horní Kaliště, that would serve as a basis for future detailed measurements. Prior to the field measurements I assembled existing materials and carried out a reconnaissance. After finding the density of current minor control, the detailed minor horizontal control was completed with 14 points. 7 of them make the subject of this dissertation. Surveying work was carried out using geodetic and GPS methods. As a geodetic method I used the method of plane network, from GPS methods I chose the GPS fast static method. Next I created necessary graphic attachments. Finally, I used all the gained data to conduct the evaluation and comparison of the particular activities and technologies.
34

Návrh a vybudování sítě bodů podrobného polohového bodového pole metodou geodetickou a GPS. / Design and Development of the Network of Points of the Detailed Minor Horizontal Control using Geodetic and GPS Methods

ŽAHOUREK, Jakub January 2012 (has links)
This thesis deals with "Design and Development of the Network of Points of the Detailed Minor Horizontal Control using Geodetic and GPS Methods" in the cadastral territory Jenín and Horní Kaliště. Using the map basis I conducted the reconnaissance and analysis of the current level of the minor control points in the target territory. Next I stabilized 14 new points of the DMHC, however, this thesis uses only 7 of these 14 points. The work aims to analyze the current level of the minor control and if needed to increase the field density for detailed large-scale mapping. For this purpose I used total station Leica TCR 407 power for the geodetic method and Trimble 4600LS device for the GPS method. Consequently I analyzed the accuracy of both methods.
35

Návrh a vybudování sítě bodů podrobného polohového bodového pole metodou geodetickou a GPS v povodí Jenínského potoka / Design and Development of the Network of Points of the Detailed Minor Horizontal Control by the Geodetic nad GPS Methods in the Basin of the Jeninsky Stream

HOFMANOVÁ, Lucie January 2010 (has links)
This Graduation Thesis was elaborated on the following topic: ``Design and Development of the Network of Points of the Detailed Minor Horizontal Control (``DMHC{\crq}q) by the Geodetic and GPS Methods in the Basin of the Jeninsky Stream{\crq}q. The goal of the Thesis was to reconnoitre the part of the basin of the Jeninsky Stream, analyze current level of the minor control in this locality, amend current horizontal minor control in the density for detailed large-scale mapping and locate minor control by the geodetic and GPS methods. The given locality was reconnoitred based on the map basis and geodetic data. Afterwards, I carried out monumentation of new points of the DMHC and then their positional determination by the geodetic and GPS methods. The network of 16 points of the DMHC was created, for this Graduation Thesis was used 8 of them. The electronic total station Leica TCR 407 power was used for the determination by the geodetic method and Trimble 4600LS device was used for the GPS method.
36

Discrete gate sizing and timing-driven detailed placement for the design of digital circuits / Dimensionamento de portas discreto e posicionamento detalhado dirigido a desempenho para o projeto de circuitos digitais

Flach, Guilherme Augusto January 2015 (has links)
Ferramentas de projeto de circuitos integrados (do inglˆes, electronic design automation, ou simplesmente EDA) tˆem um papel fundamental na crescente complexidade dos projetos de circuitos digitais. Elas permitem aos projetistas criar circuitos com um n´umero de componentes ordens de grandezas maior do que seria poss´ıvel se os circuitos fossem projetados `a m˜ao como nos dias iniciais da microeletrˆonica. Neste trabalho, dois importantes problemas em EDA ser˜ao abordados: dimensionamento de portas e posicionamento detalhado dirigido a desempenho. Para dimensionamento de portas, uma nova metodologia de relaxac¸ ˜ao Lagrangiana ´e apresentada baseada em informac¸ ˜ao de temporarizac¸ ˜ao locais e propagac¸ ˜ao de sensitividades. Para posicionamento detalhado dirigido a desempenho, um conjunto de movimentos de c´elulas ´e criado usando uma formac¸ ˜ao ´otima atenta `a forc¸a de alimentac¸ ˜ao para o balanceamento de cargas. Nossos resultados experimentais mostram que tais t´ecnicas s˜ao capazes de melhorar o atual estado-da-arte. / Electronic design automation (EDA) tools play a fundamental role in the increasingly complexity of digital circuit designs. They empower designers to create circuits with several order of magnitude more components than it would be possible by designing circuits by hand as was done in the early days of microelectronics. In this work, two important EDA problems are addressed: gate sizing and timing-driven detailed placement. They are studied and new techniques developed. For gate sizing, a new Lagrangian-relaxation methodology is presented based on local timing information and sensitivity propagation. For timing-driven detailed placement, a set of cell movement methods are created using drive strength-aware optimal formulation to driver/sink load balancing. Our experimental results shows that those techniques are able to improve the current state-of-the-art.
37

Algoritmo de posicionamento analítico-detalhado guiado a caminhos críticos / Analytical detailed placement algorithm for critical paths

Monteiro, Jucemar Luis January 2014 (has links)
O posicionamento das portas lógicas tem papel fundamental na qualidade de um circuito digital. A qualidade do posicionamento impacta diretamente na tamanho do circuito, no tempo de propagação dos sinais, consumo de energia, área com problemas de aquecimento, demanda de recursos de roteamento, etc. Desse modo, algoritmos de posicionamento de portas lógicas tem sido investigado por muitas décadas em busca de soluções de posicionamento com melhor qualidade e com o menor tempo de execução possível. Além disso, o posicionamento de portas lógicas é um problema de otimização combinatorial e ele é um dos problemas pertencentes a classe NP-Difícil. Desse modo, obter a solução ótima em tempo computalcional razoável é praticamente impossível. Portanto, a investigação de técnicas e algoritmos que provenham melhores soluções do que as obtidas atualmente para o posicionamento de portas lógicas é de fundamental importância para o contínuo avanço da indústria de microeletrônica. Neste trabalho foi proposto um algoritmo de posicionamento analítico detalhado para minimizar as violações no tempo de propagação dos sinais de dados. O algoritmo proposto é uma adaptação de um algoritmo de posicionamento analítico quadrático da etapa de posicionamento global para atuar sobre as portas lógicas combinacionais dos caminhos críticos na etapa de posicionamento detalhado. As portas lógicas movimentadas pela formulação propostas são aquelas combinacionais pertencentes aos caminhos críticos e aquelas que são vizinhas no primeiro nível lógico das pertencentes aos caminhos críticos. O algoritmo proposto opera somente sobre os caminhos com violações no tempo de propagação de late dos sinais de dados. A validação experimental do algoritmo proposto mostrou que as violações de Worst Negative Slack (WNS) e Total Negative Slack (TNS) foram reduzidas, respectivamente, em até 47,9% e 59,6% no tempo de propagação dos sinais de dados. Portanto, a qualidade do posicionamento detalhado incrementa em até 5%. Por outro lado, as violações de Average Bin Utilization (ABU) incrementam em até 5,5%. O algoritmo de posicionamento analítico detalhado opera sobre no máximo 1% do total de portas lógicas dos circuitos analisados. / The logical gates placement has a fundamental impact on the placement quality of the circuit. The placement quality impacts directly on circuit size, timing propagation, power consumption, hotspot areas, etc. Therefore, placement algorithms have been researched for a long time to improve placement quality with less runtime to find a good solution to the placement problem. In this work was proposed an analytical detailed placement algorithm to minimize timing propagation violations. The proposed algorithm was adapted from a quadratic algorithm of the global placement step to handle critical paths in detailed placement step. Detailed quadratic algorithm moves gates in critical paths and the gates in the first deep logical level of the ones in critical paths that are the immediate neighbors. The detailed analytical algorithm works only in combinational gates that are part of critical paths and for ones in late critical paths. The experimental validation of the proposed detailed analytical algorithm shows a reduction in WNS and TNS violation, respectively, up to 47.9% and 59.6% in timing propagation. Therefore, detailed placement quality had improved up to 5%. Otherwise, ABU penalty also increased up to 5.5%. In our formulation is moved up to 1% of the total number of gates in the benchmarks.
38

Advanced Hybrid Solar Cell Approaches for Future Generation Ultra-High Efficiency Photovoltaic Devices

January 2014 (has links)
abstract: Increasing the conversion efficiencies of photovoltaic (PV) cells beyond the single junction theoretical limit is the driving force behind much of third generation solar cell research. Over the last half century, the experimental conversion efficiency of both single junction and tandem solar cells has plateaued as manufacturers and researchers have optimized various materials and structures. While existing materials and technologies have remarkably good conversion efficiencies, they are approaching their own limits. For example, tandem solar cells are currently well developed commercially but further improvements through increasing the number of junctions struggle with various issues related to material interfacial defects. Thus, there is a need for novel theoretical and experimental approaches leading to new third generation cell structures. Multiple exciton generation (MEG) and intermediate band (IB) solar cells have been proposed as third generation alternatives and theoretical modeling suggests they can surpass the detailed balance efficiency limits of single junction and tandem solar cells. MEG or IB solar cell has a variety of advantages enabling the use of low bandgap materials. Integrating MEG and IB with other cell types to make novel solar cells (such as MEG with tandem, IB with tandem or MEG with IB) potentially offers improvements by employing multi-physics effects in one device. This hybrid solar cell should improve the properties of conventional solar cells with a reduced number of junction, increased light-generated current and extended material selections. These multi-physics effects in hybrid solar cells can be achieved through the use of nanostructures taking advantage of the carrier confinement while using existing solar cell materials with excellent characteristics. This reduces the additional cost to develop novel materials and structures. In this dissertation, the author develops thermodynamic models for several novel types of solar cells and uses these models to optimize and compare their properties to those of existing PV cells. The results demonstrate multiple advantages from combining MEG and IB technology with existing solar cell structures. / Dissertation/Thesis / Ph.D. Electrical Engineering 2014
39

Algoritmo de posicionamento analítico-detalhado guiado a caminhos críticos / Analytical detailed placement algorithm for critical paths

Monteiro, Jucemar Luis January 2014 (has links)
O posicionamento das portas lógicas tem papel fundamental na qualidade de um circuito digital. A qualidade do posicionamento impacta diretamente na tamanho do circuito, no tempo de propagação dos sinais, consumo de energia, área com problemas de aquecimento, demanda de recursos de roteamento, etc. Desse modo, algoritmos de posicionamento de portas lógicas tem sido investigado por muitas décadas em busca de soluções de posicionamento com melhor qualidade e com o menor tempo de execução possível. Além disso, o posicionamento de portas lógicas é um problema de otimização combinatorial e ele é um dos problemas pertencentes a classe NP-Difícil. Desse modo, obter a solução ótima em tempo computalcional razoável é praticamente impossível. Portanto, a investigação de técnicas e algoritmos que provenham melhores soluções do que as obtidas atualmente para o posicionamento de portas lógicas é de fundamental importância para o contínuo avanço da indústria de microeletrônica. Neste trabalho foi proposto um algoritmo de posicionamento analítico detalhado para minimizar as violações no tempo de propagação dos sinais de dados. O algoritmo proposto é uma adaptação de um algoritmo de posicionamento analítico quadrático da etapa de posicionamento global para atuar sobre as portas lógicas combinacionais dos caminhos críticos na etapa de posicionamento detalhado. As portas lógicas movimentadas pela formulação propostas são aquelas combinacionais pertencentes aos caminhos críticos e aquelas que são vizinhas no primeiro nível lógico das pertencentes aos caminhos críticos. O algoritmo proposto opera somente sobre os caminhos com violações no tempo de propagação de late dos sinais de dados. A validação experimental do algoritmo proposto mostrou que as violações de Worst Negative Slack (WNS) e Total Negative Slack (TNS) foram reduzidas, respectivamente, em até 47,9% e 59,6% no tempo de propagação dos sinais de dados. Portanto, a qualidade do posicionamento detalhado incrementa em até 5%. Por outro lado, as violações de Average Bin Utilization (ABU) incrementam em até 5,5%. O algoritmo de posicionamento analítico detalhado opera sobre no máximo 1% do total de portas lógicas dos circuitos analisados. / The logical gates placement has a fundamental impact on the placement quality of the circuit. The placement quality impacts directly on circuit size, timing propagation, power consumption, hotspot areas, etc. Therefore, placement algorithms have been researched for a long time to improve placement quality with less runtime to find a good solution to the placement problem. In this work was proposed an analytical detailed placement algorithm to minimize timing propagation violations. The proposed algorithm was adapted from a quadratic algorithm of the global placement step to handle critical paths in detailed placement step. Detailed quadratic algorithm moves gates in critical paths and the gates in the first deep logical level of the ones in critical paths that are the immediate neighbors. The detailed analytical algorithm works only in combinational gates that are part of critical paths and for ones in late critical paths. The experimental validation of the proposed detailed analytical algorithm shows a reduction in WNS and TNS violation, respectively, up to 47.9% and 59.6% in timing propagation. Therefore, detailed placement quality had improved up to 5%. Otherwise, ABU penalty also increased up to 5.5%. In our formulation is moved up to 1% of the total number of gates in the benchmarks.
40

Generation of H-Atom Pulses and Associative Desorption of Hydrogen Isotopologues from Metal Surfaces

Kaufmann, Sven 11 October 2017 (has links)
No description available.

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