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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

Development of three-dimensional profiled woven fabrics on narrow fabric looms

Fazeli, Monireh, Kern, Martin, Hoffmann, Gerald, Cherif, Chokri 18 September 2019 (has links)
Three-dimensional (3D) profiled woven fabrics with varying cross-sections along the component parts are needed in a number of industrial applications. One of the main advantages of the ribbon loom weaving technique is the ability to produce highly diverse structures with open or closed edges. The realization of 3D profiled woven fabrics that satisfy the requirements is directly connected to the ability to process high-performance fibers in the weft direction. The processing of high-performance yarns in the weft direction with low fiber damage will open new application areas for shuttle weaving machines. By employing modified mechanical loom elements, the variety of producible structures can be increased significantly.
22

Analysis And Integration Of A Debris Model In The Virtual Range Projec

Robledo, Luis 01 January 2004 (has links)
After the accident of the STS 107 Columbia Space Shuttle, great concern has been focused on the risk associated to the population on the ground. Before this accident happened, re-entry routes as well as risk calculation of were not of public concern. Two issues that have been raised from this lamentable accident relate to spacecraft security and to public safety. The integration of a debris model has been part of the original conceptual architecture of the Virtual Range Project. Its integration has been considered as a specific research due to the complexity of the models and the difficulties to obtain them since the commercial off-the-shelf available software seems to be less accessible. This research provides solid information concerning what debris fragmentation models are, their fundamentals, their weaknesses and strengths. The research provides information of the main debris models being currently used by NASA which have direct relationship with the space programs conducted. This study also addresses the integration of a debris model into the Virtual Range Project. We created a provisional model based on the distribution of the Columbia debris fragments over Texas and part of Louisiana in order to create an analytical methodology as well. This analysis shows a way of integrating this debris model with a Geographic Information System as well as the integration of several raster and vector data sets which will provide the source data to compute the calculations. This research uses population data sets that allow the determination of the number of people at risk on the ground. The graphical and numerical analysis made can lead to the determination of new and more secure re-entry trajectories as well as further population-related security issues concerning this type of flights.
23

Using The Software Adapter To Connect Legacy Simulation Models To The Rti

Rachapalli, Deepak Kumar 01 January 2006 (has links)
The establishment of a network of persistent shared simulations depends on the presence of a robust standard for communicating state information between those simulations. The High Level Architecture (HLA) can serve as the basis for such a standard. While the HLA is architecture, not software, use of Run Time Infrastructure (RTI) software is required to support operations of a federation execution. The integration of RTI with existing simulation models is complex and requires a lot of expertise. This thesis implements a less complex and effective interaction between a legacy simulation model and RTI using a middleware tool known as Distributed Manufacturing Simulation (DMS) adapter. Shuttle Model, an Arena based discrete-event simulation model for shuttle operations, is connected to the RTI using the DMS adapter. The adapter provides a set of functions that are to be incorporated within the Shuttle Model, in a procedural manner, in order to connect to RTI. This thesis presents the procedure when the Shuttle Model connects to the RTI, to communicate with the Scrub Model for approval of its shuttle's launch.
24

Model Identification for the Space Shuttle Main Engine High Pressure Oxidizer Turbopump

Brown, Joseph R. January 1992 (has links)
No description available.
25

Análise de imagens baseada em objetos geográficos (GEOBIA) aplicada ao mapeamento da transição entre cinturão orogênico do atlântico e bacia sedimentar do Paraná / Analysis of images based on geographic objects (GEOBIA) applied to the transition mapping between Atlantics orogenic belt and Paranas sedimentary basin

Kawata, Leonardo Takei 11 November 2014 (has links)
O uso de geotecnologias pode contribuir de forma muito significativa para os estudos em geomorfologia. Considerando os principais componentes desta ciência, morfografia, morfometria, morfogênese e morfocronologia, os modelos digitais para a representação da superfície da Terra podem ser amplamente utilizados na aquisição de muitas destas informações. O uso de Modelos Digitais de Elevação (MDE) há alguns anos, já é uma realidade em estudos envolvendo geomorfologia. A sua utilização permite a aquisição de variáveis e parâmetros objetivos que podem servir à definição de critérios para o agrupamento de unidades geomorfológicas. Podendo, portanto, ser um instrumento valioso para mapeamento de áreas amplas em escalas de 1:50.000 e 1:100.000. Para tanto, é necessário definir os critérios coerentes e os algoritmos de segmentação que oferecem os melhores resultados para as diversas áreas de estudo. Os MDE gerados pela missão Shuttle Radar Topography Mission (SRTM) são de vasta abrangência e contemplam todo o território nacional brasileiro. Portanto, os dados gerados pela missão podem ser uma importante fonte de informação para mapeamentos com metodologia única. O alcance deste objetivo não garante avanços metodológicos na cartografia geomorfológica, tendo em vista que a possibilidade de comparação entre diferentes cartas geomorfológicas de detalhe ainda é restrita. / Geotechnologies can contribute significantly to geomorphology studies. Whereas the main principles of this science, mophography, morphometry, morphogenesis and morphochronology, the digital models used to represent the Earth surface can be widely utilized in a bunch of these data. Lately, the use of Digital Elevation Model (DEM) can be considered a reality in geomorphology studies. The utilization allows the acquisition of objective variables and parameters that can be suitable for definition of geomorphological units. Hence, can be a valuable tool for wide area mapping using 1:50.000 and 1:100.000 scales. For that reason, it is necessary to define coherent criteria and the proper segmentation algorithm in order to reach better results for different study cases. DEM provided by Shuttle Radar Topography Mission (SRTM) are wide range and cover the whole national territory. Therefore, data provided by this mission can be an important information for a single methodology mapping project.
26

Correlação entre condensado do exalado pulmonar, teste de caminhada de seis minutos e shuttle walk test em indivíduos cardiopatas / Correlation between exhaled breath condensate, six minutes walk test and shuttle walk test in heart disease

Nascimento, Marina Neves do 16 May 2014 (has links)
Introdução: As doenças cardíacas ou do aparelho circulatório são as principais causas de morte na população brasileira, sendo responsável por um terço dos óbitos. Embora o tratamento conservador seja amplamente adotado, grande parte das doenças cardiovasculares necessita e tem como tratamento a cirurgia cardíaca, da qual as mais comuns são a cirurgia de revascularização do miocárdio (CRVM) e de troca valvar. Atualmente existem diversos estudos avaliando a função pulmonar ou a capacidade funcional para o acompanhamento do tratamento conservador ou em situação pré-operatória, porém estudos avaliando e correlacionando essas variáveis no pré-cirúrgico são escassos na literatura científica não sendo possível averiguar a existência da relação entre os níveis de nitrito e nitrato e o desempenho nos testes de capacidade funcional. Objetivo: Avaliar a correlação nitrito/nitrato (NOx) do condensado do exalado pulmonar (CEP) e a distância caminhada nos testes de caminhada de 6 minutos (TC6) e shuttle walk test (SWT), além de verificar se a utilização de medicações contendo betabloqueadores, nitrato ou enzima conversora de angiotensina (IECA) podem influenciar nas concentrações de nitrito/nitrato no CEP e nas distâncias caminhadas no TC6 e no SWT e comparar seu comportamento entre valvopatas e coronariopatas no pré operatório de cirurgia cardíaca. Metodologia: Foram selecionados 73 pacientes, dos quais 28 eram coronariopatas e 45 valvopatas, de ambos os sexos, com idade entre 20 e 80 anos, feita coleta do CEP para análise do NOx e submetidos ao TC6 e ao SWT para avaliação da distância caminhada. Resultados: Na análise das concentrações de NOx do CEP não foi encontrada diferença estatisticamente significativa entre as medicações utilizadas via oral contendo nitrato (dinitrato de isossorbida), IECA (captopril ou enalapril) e/ou betabloqueador ou entre os pacientes do grupo coronariopata e grupo valvopata (p>0,05). Houve diferença estatisticamente significativa no TC6 nos valores de frequência cardíaca (FC) inicial, final e repouso e no valor referente à dispnéia final, e no SWT nos valores de FC inicial, final e repouso, na pressão arterial sistólica (PAS) inicial e no valor referente à dispnéia final entre os grupos coronariopata e valvopata. No entanto, foram interrompidos 4 TC6 e 7 SWT do grupo coronariopata devido ao desencadeamento de dor precordial, fato não ocorrido no grupo valvopata, apresentando nível de significância. A FC inicial e de repouso no TC6 e a FC final no SWT dos pacientes que não ingeriram nenhum medicamento antes do teste é diferente em relação à dos pacientes que fizeram uso de quaisquer medicamentos descritos antes do teste sugerindo a ação de medicamentos que modulam a FC como os betabloqueadores. Foi constatado correlação positiva moderada entre o NOx do CEP e os valores de PAS inicial e final de coronariopatas e correlação negativa fraca a moderada entre o NOx do CEP e os valores de FC final e de dispnéia final nos valvopatas no TC6, além da correlação positiva moderada entre o NOx do CEP e os valores de PAS inicial de indivíduos coronariopatas e correlação negativa fraca a moderada entre o NOx do CEP e os valores de FC inicial nos valvopatas no SWT. Foi identificado correlação negativa moderada na distância caminhada no TC6 e no SWT apenas nos indivíduos coronariopatas. Conclusões: Não foram identificadas influências do uso de medicações betabloqueadoras, nitrato ou IECA sobre a dosagem de NOx ou a distância caminhada em nenhum dos testes e em nenhum dos grupos, no entanto coronariopatas com níveis mais elevados de NOx apresentaram uma distância deambulada menor. / Introduction: Heart disease or circulatory system diseases are the leading causes of death in our population, accounting for one third of deaths. Although conservative treatment is widely adopted, part of cardiovascular disease treatment demands heart surgery, of which the most common are coronary artery bypass grafting (CABG) and valve replacement. Currently there are many studies evaluating lung function or functional capacity for monitoring of conservative treatment or preoperative situation, but studies assessing and correlating these variables in pre surgical are rare in the literature is not possible to ascertain the existence of the relationship between levels of nitrite and nitrate (NOx) in exhaled breath condensate (EBC) and performance in functional ability tests. Methods: were selected 73 patients, 28 with coronary artery diseas and 45 with heart valve disease of both genders, aged 20 to 80 years old. The EBC was collected for analysis of NOx and performed the six minutes walking test (6MWT) and shuttle walk test (SWT) to evaluate the distance walked. Results: the analysis of the concentrations of NOx in EBC has no statistically significant difference found between the medications used, such as oral nitrate (isosorbide dinitrate), ace inhibitors (captopril or enalapril) and/or beta-blockers in both coronary artery disease and heart valve disease (p> 0.05). There was a statistically significant difference in 6MWT for HR initial, final and rest and final dyspnea, and in SWT for HR initial, final and rest, the initial SBP and the final dyspnea between the coronary artery disease e heart valve disease. However, were interrupted 4 6MWT and 7 SWT from coronary artery disease related to chest pain, this fact was not related in patients with valve disease, presenting a significance level. The initial and resting HR during the 6MWT and in SWT final HRr patients not ingesting any medication before the test is different from patients who used any medications before the test, suggesting the action of drugs that modulate the HR, such as beta blockers. Moderate positive correlation was found between the NOx in EBC and SBP initial and final in coronary disease and weak to moderate correlation between the NOx in EBC and final HR and final dyspnea in 6MWT from heart valve disease. Besides the positive moderate correlation between NOx in the EBC and the SBP initial in coronary disease during 6MWT and weak to moderate negative correlation between NOx in the EBC and the HR initial in valve disease during SWT. Moderate negative correlation was identified in the distance walked during the 6MWT and SWT only between individuals with coronary artery disease. Conclusions: the use of beta-blocker drugs, ace inhibitors or nitrate evidenciates no influence on the NOx or on the distance walked in any tests, and none of the groups, however, individuals with coronary artery disease showed higher NOx levels and performed lower distance walked.
27

Correlação entre condensado do exalado pulmonar, teste de caminhada de seis minutos e shuttle walk test em indivíduos cardiopatas / Correlation between exhaled breath condensate, six minutes walk test and shuttle walk test in heart disease

Marina Neves do Nascimento 16 May 2014 (has links)
Introdução: As doenças cardíacas ou do aparelho circulatório são as principais causas de morte na população brasileira, sendo responsável por um terço dos óbitos. Embora o tratamento conservador seja amplamente adotado, grande parte das doenças cardiovasculares necessita e tem como tratamento a cirurgia cardíaca, da qual as mais comuns são a cirurgia de revascularização do miocárdio (CRVM) e de troca valvar. Atualmente existem diversos estudos avaliando a função pulmonar ou a capacidade funcional para o acompanhamento do tratamento conservador ou em situação pré-operatória, porém estudos avaliando e correlacionando essas variáveis no pré-cirúrgico são escassos na literatura científica não sendo possível averiguar a existência da relação entre os níveis de nitrito e nitrato e o desempenho nos testes de capacidade funcional. Objetivo: Avaliar a correlação nitrito/nitrato (NOx) do condensado do exalado pulmonar (CEP) e a distância caminhada nos testes de caminhada de 6 minutos (TC6) e shuttle walk test (SWT), além de verificar se a utilização de medicações contendo betabloqueadores, nitrato ou enzima conversora de angiotensina (IECA) podem influenciar nas concentrações de nitrito/nitrato no CEP e nas distâncias caminhadas no TC6 e no SWT e comparar seu comportamento entre valvopatas e coronariopatas no pré operatório de cirurgia cardíaca. Metodologia: Foram selecionados 73 pacientes, dos quais 28 eram coronariopatas e 45 valvopatas, de ambos os sexos, com idade entre 20 e 80 anos, feita coleta do CEP para análise do NOx e submetidos ao TC6 e ao SWT para avaliação da distância caminhada. Resultados: Na análise das concentrações de NOx do CEP não foi encontrada diferença estatisticamente significativa entre as medicações utilizadas via oral contendo nitrato (dinitrato de isossorbida), IECA (captopril ou enalapril) e/ou betabloqueador ou entre os pacientes do grupo coronariopata e grupo valvopata (p>0,05). Houve diferença estatisticamente significativa no TC6 nos valores de frequência cardíaca (FC) inicial, final e repouso e no valor referente à dispnéia final, e no SWT nos valores de FC inicial, final e repouso, na pressão arterial sistólica (PAS) inicial e no valor referente à dispnéia final entre os grupos coronariopata e valvopata. No entanto, foram interrompidos 4 TC6 e 7 SWT do grupo coronariopata devido ao desencadeamento de dor precordial, fato não ocorrido no grupo valvopata, apresentando nível de significância. A FC inicial e de repouso no TC6 e a FC final no SWT dos pacientes que não ingeriram nenhum medicamento antes do teste é diferente em relação à dos pacientes que fizeram uso de quaisquer medicamentos descritos antes do teste sugerindo a ação de medicamentos que modulam a FC como os betabloqueadores. Foi constatado correlação positiva moderada entre o NOx do CEP e os valores de PAS inicial e final de coronariopatas e correlação negativa fraca a moderada entre o NOx do CEP e os valores de FC final e de dispnéia final nos valvopatas no TC6, além da correlação positiva moderada entre o NOx do CEP e os valores de PAS inicial de indivíduos coronariopatas e correlação negativa fraca a moderada entre o NOx do CEP e os valores de FC inicial nos valvopatas no SWT. Foi identificado correlação negativa moderada na distância caminhada no TC6 e no SWT apenas nos indivíduos coronariopatas. Conclusões: Não foram identificadas influências do uso de medicações betabloqueadoras, nitrato ou IECA sobre a dosagem de NOx ou a distância caminhada em nenhum dos testes e em nenhum dos grupos, no entanto coronariopatas com níveis mais elevados de NOx apresentaram uma distância deambulada menor. / Introduction: Heart disease or circulatory system diseases are the leading causes of death in our population, accounting for one third of deaths. Although conservative treatment is widely adopted, part of cardiovascular disease treatment demands heart surgery, of which the most common are coronary artery bypass grafting (CABG) and valve replacement. Currently there are many studies evaluating lung function or functional capacity for monitoring of conservative treatment or preoperative situation, but studies assessing and correlating these variables in pre surgical are rare in the literature is not possible to ascertain the existence of the relationship between levels of nitrite and nitrate (NOx) in exhaled breath condensate (EBC) and performance in functional ability tests. Methods: were selected 73 patients, 28 with coronary artery diseas and 45 with heart valve disease of both genders, aged 20 to 80 years old. The EBC was collected for analysis of NOx and performed the six minutes walking test (6MWT) and shuttle walk test (SWT) to evaluate the distance walked. Results: the analysis of the concentrations of NOx in EBC has no statistically significant difference found between the medications used, such as oral nitrate (isosorbide dinitrate), ace inhibitors (captopril or enalapril) and/or beta-blockers in both coronary artery disease and heart valve disease (p> 0.05). There was a statistically significant difference in 6MWT for HR initial, final and rest and final dyspnea, and in SWT for HR initial, final and rest, the initial SBP and the final dyspnea between the coronary artery disease e heart valve disease. However, were interrupted 4 6MWT and 7 SWT from coronary artery disease related to chest pain, this fact was not related in patients with valve disease, presenting a significance level. The initial and resting HR during the 6MWT and in SWT final HRr patients not ingesting any medication before the test is different from patients who used any medications before the test, suggesting the action of drugs that modulate the HR, such as beta blockers. Moderate positive correlation was found between the NOx in EBC and SBP initial and final in coronary disease and weak to moderate correlation between the NOx in EBC and final HR and final dyspnea in 6MWT from heart valve disease. Besides the positive moderate correlation between NOx in the EBC and the SBP initial in coronary disease during 6MWT and weak to moderate negative correlation between NOx in the EBC and the HR initial in valve disease during SWT. Moderate negative correlation was identified in the distance walked during the 6MWT and SWT only between individuals with coronary artery disease. Conclusions: the use of beta-blocker drugs, ace inhibitors or nitrate evidenciates no influence on the NOx or on the distance walked in any tests, and none of the groups, however, individuals with coronary artery disease showed higher NOx levels and performed lower distance walked.
28

Análise de imagens baseada em objetos geográficos (GEOBIA) aplicada ao mapeamento da transição entre cinturão orogênico do atlântico e bacia sedimentar do Paraná / Analysis of images based on geographic objects (GEOBIA) applied to the transition mapping between Atlantics orogenic belt and Paranas sedimentary basin

Leonardo Takei Kawata 11 November 2014 (has links)
O uso de geotecnologias pode contribuir de forma muito significativa para os estudos em geomorfologia. Considerando os principais componentes desta ciência, morfografia, morfometria, morfogênese e morfocronologia, os modelos digitais para a representação da superfície da Terra podem ser amplamente utilizados na aquisição de muitas destas informações. O uso de Modelos Digitais de Elevação (MDE) há alguns anos, já é uma realidade em estudos envolvendo geomorfologia. A sua utilização permite a aquisição de variáveis e parâmetros objetivos que podem servir à definição de critérios para o agrupamento de unidades geomorfológicas. Podendo, portanto, ser um instrumento valioso para mapeamento de áreas amplas em escalas de 1:50.000 e 1:100.000. Para tanto, é necessário definir os critérios coerentes e os algoritmos de segmentação que oferecem os melhores resultados para as diversas áreas de estudo. Os MDE gerados pela missão Shuttle Radar Topography Mission (SRTM) são de vasta abrangência e contemplam todo o território nacional brasileiro. Portanto, os dados gerados pela missão podem ser uma importante fonte de informação para mapeamentos com metodologia única. O alcance deste objetivo não garante avanços metodológicos na cartografia geomorfológica, tendo em vista que a possibilidade de comparação entre diferentes cartas geomorfológicas de detalhe ainda é restrita. / Geotechnologies can contribute significantly to geomorphology studies. Whereas the main principles of this science, mophography, morphometry, morphogenesis and morphochronology, the digital models used to represent the Earth surface can be widely utilized in a bunch of these data. Lately, the use of Digital Elevation Model (DEM) can be considered a reality in geomorphology studies. The utilization allows the acquisition of objective variables and parameters that can be suitable for definition of geomorphological units. Hence, can be a valuable tool for wide area mapping using 1:50.000 and 1:100.000 scales. For that reason, it is necessary to define coherent criteria and the proper segmentation algorithm in order to reach better results for different study cases. DEM provided by Shuttle Radar Topography Mission (SRTM) are wide range and cover the whole national territory. Therefore, data provided by this mission can be an important information for a single methodology mapping project.
29

A REAL-TIME TELEMETRY SIMULATOR OF THE IUS SPACECRAFT

Drews, Michael E., Forman, Douglas A., Baker, Damon M., Khazoyan, Louis B., Viazzo, Danilo 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / A real-time telemetry simulator of the IUS spacecraft has recently entered operation to train Flight Control Teams for the 1aunch of the AXAF telescope from the Shuttle. The simulator has proven to be a successful higher fidelity implementation of its predecessor, while affirming the rapid development methodology used in its design. Although composed of COTS hardware and software, the system simulates the full breadth of the mission: Launch, Pre-Deployment-Checkout, Burn Sequence, and AXAF/IUS separation. Realism is increased through patching the system into the operations facility to simulate IUS telemetry, Shuttle telemetry, and the Tracking Station link (commands and status message).
30

Data Relay System for Space Shuttle and Payload Pre-Launch Checkout

O'Donnell, Hugh B., Wise, Thomas E., Ngo, David Q. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1987 / Town and Country Hotel, San Diego, California / Engineering requirements and design characteristics of the coherent throughput relay system which supports East Coast pre-launch checkout of NASA's Space Shuttle and its Payloads are presented. The Relay system is required to provide communications through NASA's Tracking and Data Relay Satellite System for the Shuttle and Payload-Users while they are encapsulated in the launch preparation facilities at the John F. Kennedy Space Center and the Eastern Test Range, Florida. The Relay system is required to be transparent to its users' data at all rates up to three MB/s at S-band and 300 MB/s at Ku-band. Noise and group-delay distortion are major contributors to wide band RF signal degradation. These were major factors in the Relay system design. Antenna design, pointing angle and location were constrained by the need to maximize end-to-end RF signal isolation at both S-band and KU-band, simultaneous forward and return frequencies. System characteristics and link analysis are also presented. In addition, a similar Data Relay located at Vandenberg Air Force Base is briefly described.

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