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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

Improving and Expanding the Capabilities of the Poly-Picosatellite Orbital Deployer

Pignatelli, David 01 October 2014 (has links)
The Poly-Picosatellite Orbital Deployer (P-POD) has undergone a series of revisions over the years. The latest revision, described in this Master’s Thesis, incorporates new capabilities like EMI shielding, an inert gas purge system, and an electrical interface to the CubeSats after they are integrated into the P-POD. Additionally, some mass reduction modifications are made to the P-POD, while its overall strength is increased. The P-POD inert gas purge system successfully flew, on a previous revision P-POD. The P-POD components are analyzed to a set of dynamic loads for qualification, and successfully undergoes random vibration qualification testing. The P-POD encounters some problems in thermal vacuum cycling qualification and EMI testing, but there is evidence that the issues can be mitigated. A path forward is laid out to complete both sets of testing.
32

Srovnání metody horsemanshipu a anglického stylu ježdění

Smékalová, Kamila January 2019 (has links)
The objective of the thesis entitled The Comparison of the Horsemanship Method and the English Riding Style is to characterise the horsemanship method and the English riding style on the basis of literature search, to describe and compare the two methods in the monitored groups of horses as regards the ground work, saddle breaking and under-saddle work, and to generally compare horsemanship and English riding. The literature review describes the characteristics, principles and recommended training practices for the two methods under comparison. The practical part of this thesis compares the two methods of horse training. A comparative report has been created as a supporting tool to assess the training of ten horses. The assessment and subsequent comparison were based on four aspects: the physical and the mental aspects of the horse, the rider's confidence in the horse, and time in order to consider all the factors involved in horse training. Furthermore, the thesis characterises the monitored horses and the training used, providing a comparison for each of the training stages – ground work, saddle breaking and work under saddle. The thesis concludes by providing a general comparison of the two horse training methods. Horsemanship showed better outcomes as regards the physical and the mental aspects of the horse as well as the rider’s confidence in the horse. On the contrary, the horses trained using the English riding style took less time to train. The biggest differences were observed in the early stages of training.
33

Integration and Qualification of the P-PODs on the Vega Maiden Flight

Nugent, Ryan 01 December 2016 (has links) (PDF)
On February 13, 2012, California Polytechnic State University, San Luis Obispo flew three Poly-Picosatellite Orbital Deployers (P-PODs), carrying seven European University CubeSats sponsored by the European Space Agency (ESA), on the Vega Maiden Flight. This was the first time CubeSats shared a ride to space with other payloads on an ESA-owned launch opportunity. In order to meet launch requirements, it must be proven through proper documentation that the P-POD would operate properly and not interfere with the launch vehicle or other payloads on the mission. This thesis outlines the program flow, required documentation, and issues encountered during the launch campaign to get the P-PODs properly qualified and integrated on to the Vega launch vehicle. This mission required Cal Poly to create several unique solutions, which were only implemented for this mission, in order to meet unique technical requirements and programmatic goals. As a result of this mission’s success the ESA Education Office implemented the Fly Your Satellite Program, which has continued to support and launch CubeSats developed by European universities.
34

Modern Statistical Methods and Uncertainty Quantification for Evaluating Reliability of Nondestructive Evaluation Systems

Knopp, Jeremy Scott 13 May 2014 (has links)
No description available.
35

Experimental Investigation into Thermo-Acoustic Instability in Pre-Mixed, Pre-Vaporized Bluff-Body Stabilized Flames

Monfort, Jeffrey Ross 27 August 2015 (has links)
No description available.
36

Designing a Walkable Suburban Landscape: New Urbanism and Light Rail as Methodologies

Davidson, Kyle 09 August 2006 (has links)
The suburban landscape is a landscape of opportunity. Historically, the suburban landscape has been a desirable place for living. Because it demands the use of automobiles, it is also a landscape undesirable for pedestrians. Optimistically, through principles of New Urbanism, walkability, and mass transportation via light rail, there is an opportunity to transform the auto dominated suburban landscape into one that promotes walkability. Located in the suburbs of Alexandria, Virginia, an atypical intersection is analyzed for its characteristics of walkability. This intersection consists of several major roads converging to create a location overly dominated by busy roads and automobiles. Though there are accommodations that signify this intersection is also a place for pedestrians, a walkability checklist and a walkability study prove otherwise. The author investigates transforming this otherwise unwalkable landscape into one that promotes walkability by providing a safe, comfortable, and enjoyable experience for suburban pedestrians. Design intentions are focused on preserving much of the existing land use and not re-developing suburbia into a new urban center. Yet, through using new urbanist principles for walkability, there is the opportunity to create a new suburban center. / Master of Landscape Architecture
37

Model Reduction of Nonlinear Fire Dynamics Models

Lattimer, Alan Martin 28 April 2016 (has links)
Due to the complexity, multi-scale, and multi-physics nature of the mathematical models for fires, current numerical models require too much computational effort to be useful in design and real-time decision making, especially when dealing with fires over large domains. To reduce the computational time while retaining the complexity of the domain and physics, our research has focused on several reduced-order modeling techniques. Our contributions are improving wildland fire reduced-order models (ROMs), creating new ROM techniques for nonlinear systems, and preserving optimality when discretizing a continuous-time ROM. Currently, proper orthogonal decomposition (POD) is being used to reduce wildland fire-spread models with limited success. We use a technique known as the discrete empirical interpolation method (DEIM) to address the slowness due to the nonlinearity. We create new methods to reduce nonlinear models, such as the Burgers' equation, that perform better than POD over a wider range of input conditions. Further, these ROMs can often be constructed without needing to capture full-order solutions a priori. This significantly reduces the off-line costs associated with creating the ROM. Finally, we investigate methods of time-discretization that preserve the optimality conditions in a certain norm associated with the input to output mapping of a dynamical system. In particular, we are able to show that the Crank-Nicholson method preserves the optimality conditions, but other single-step methods do not. We further clarify the need for these discrete-time ROMs to match at infinity in order to ensure local optimality. / Ph. D.
38

Physiological and Metabolic Responses to Water-deficit and Heat Stress of Virginia-type Peanut Cultivars and Breeding Lines

Singh, Daljit 11 June 2013 (has links)
The Virginia-Carolina (VC) region including Virginia, North Carolina, and South Carolina, is the most important peanut production region for the large seeded, virginia-type peanut in the United States.  In recent years, an increased frequency of heat and drought episodes with significant effects on peanut yield was observed in the VC region.  Because limited information is available on the mechanisms virginia-type peanut develops in response to heat and water stress, the present study evaluated several physiological and metabolic characteristics and their relationship with yield for eight cultivars and breeding lines.  Experiments were conducted under rainfed and irrigated field trials in 2011 and 2012, and in a growth chamber under optimum (30/25 "C) and high temperature (40/35 "C) conditions.  The long term goal of this study is to help development of more tolerant peanut cultivars to heat and drought in the VC region. Visible symptoms of water-deficit stress were observed in peanut during the field experiments in both years.  Significant (p d 0.05) variations for yield, membrane injury, chlorophyll fluorescence (Fv/Fm ratio), specific leaf area, SPAD chlorophyll content, and relative levels of polar and non-polar metabolites were observed in response to water regime, growth stage, and genotype in both years during the field studies.  Similarly each year, the Fv/Fm ratio, organic acids, and saturated fatty acids decreased in rainfed vs. irrigated plants, while the sugar and sugar alcohol relative levels increased.  Regardless the water regime, lower levels of saturated fatty acids and sugars, and higher levels of unsaturated fatty acids and sugar alcohols were associated (p < 0.05) with higher pod yield in field conditions.  Genotypes Phillips, SPT06-07, and N05006 showed potential tolerance and N04074FCT, CHAMPS, and Bailey susceptibility to water deficit in field studies.  Significant physiological and metabolic changes were also observed in response to heat stress under controlled conditions in peanut seedlings.  A general decrease in organic acid and saturated fatty acid levels and an increase in membrane injury, sugar, and unsaturated fatty acid levels were observed under both water deficit and heat stress conditions.  Overall, results from both experiments were suggestive of natural stress responses rather than adaptive mechanisms to water deficit and heat stress of the virginia-type genotypes used in this study. Among all genotypes, SPT 06-07 showed improved tolerance to both stresses.  Our results suggest that monitoring chlorophyll fluorescence and changes in the levels of selected metabolites can be used to screen new peanut lines for drought and heat stress tolerance. / Master of Science in Life Sciences
39

Réduction de modèles par identification de systèmes et application au contrôle du sillage d'un cylindre

Weller, Jessie 14 January 2009 (has links)
L’objectif est de construire un modèle d’écoulement qui se prête bien à des problèmes de contrôle, en associant un faible nombre de degrés de liberté à la possibilité de décrire la dynamique d’un écoulement relativement complexe. Dans ce travail nous considérons un écoulement bidimensionnel laminaire autour d’un cylindre carré. Des actionneurs placés sur le cylindre permettent un contrôle actif par sou?age et aspiration. Ce contrôle peut être dé?ni par rétroaction, exploitant des mesures de la vitesse dans le sillage du cylindre. Nous construisons un modèle d’ordre réduit (ROM) des équations de Navier-Stokes incompressibles, basé sur la technique de décomposition orthogonale aux valeurs propres (POD). Une façon classique de construire un tel modèle est de réaliser une projection Galerkin des équations sur le sous-espace réduit obtenu par POD. Un tel modèle peut cependant être peu précis, voire instable. Une technique de calibration est alors mise en place pour assurer la bonne représentativité dynamique du modèle. Nous dé?nissons ensuite une stratégie pour mettre à jour le modèle au cours d’un processus d’optimisation. La méthode est en?n appliquée pour réduire la di?érence entre l’écoulement contrôlé et la solution stationnaire instable à Re = 150. / The aim is to build a ?ow model adapted for control applications combining a low number of degrees of freedom with the possibility of describing relatively complex ?ows. In this work a two-dimensional laminar ?ow past a square cylinder is considered. Actuators placed on the cylinder enable active control by blowing and suction. Proportional feedback control can then be applied using velocity measurements taken in the cylinder wake. The proper orthogonal decom- position (POD) approach is used to build a low order model of the incompressible Navier-Stokes equations. A classical way of obtaining a Reduced-Order Model (ROM) is to perform a Galerkin projection of the equations onto the subspace spanned by the POD modes. Such a model can however be inaccurate, even unstable. A calibration technique is therefore applied, leading to a model that is accurate and robust to variations of the control parameters. A strategy is then de?ned to update the model within an optimisation loop. The method is tested at Re = 150 for reducing the di?erence between the actuated ?ow ?eld and the steady unstable solution.
40

Análise da expressão do fator de transcrição TCF21/POD-1 e de genes do ciclo celular em tumores adrenocorticais humanos. / Analysis of TCF21/POD-1 transcriptor factor and cycle cells genes expression in adult adrenocortical tumors.

Passaia, Barbara dos Santos 31 May 2016 (has links)
As massas adrenocorticais são majoritariamente (70-80%) adenomas adrenocorticais (ACA). Os carcinomas adrenocorticais (ACC) são mais raros e de prognóstico restrito, com incidência de 1-2 casos por milhão, com alta taxa de reincidência (70-80%). Apesar dos tumores adrenocorticais (ACT) serem raros, no Brasil a incidência desses tumores em crianças é cerca de 10 vezes superior ao do restante do mundo, devido a uma mutação do gene TP53. Atualmente, o diagnóstico de massas adrenocorticais é realizado através dos critérios de Weiss, que possuem limitações, e por isso é intensa a busca de novos marcadores moleculares que facilite o diagnóstico de ACTs. POD-1/ TCF21 é um fator de transcrição do tipo helix-loop-helix básica (bHLH) expresso nos sítios de interação mesênquima-epitélio durante o desenvolvimento embrionário. Em ACTs, POD-1 regula a expressão endógena de SF-1 através da ligação na sequencia E-box da região promotora de SF-1, e nesses tumores parece estar relacionado negativamente com genes reguladores do ciclo celular, como BUB1B. BUB1B é um gene que codifica uma quinase com funções importantes durante o checkpoint mitótico. A expressão de BUB1B é considerada fator de prognóstico em diferentes tipos de tumores, inclusive em ACTs humanos, nos quais a expressão combinada de BUB1B e PINK1 (&#916;CtBUB1B - &#916;CtPINK1) mostrou-se um bom marcador de sobrevida em pacientes com ACC. PINK1, quinase 1 induzida por PTEN, é regulada principalmente pela mitocôndria, e em ACTs sua expressão está reduzida em ACC mais agressivos. Temos como hipótese que a expressão de POD-1 pode ter valor diferencial no diagnóstico de massas adrenocorticais, e que a análise da expressão combinada de POD-1, BUB1B e PINK1 pode ter valor diferencial para prognóstico de pacientes com ACT. Nesse trabalho foram analisados, por reação de qPCR com sondas Taqman, o cDNA obtido de 130 amostras de tumores: 79 adultos (44 ACAs e 35 ACCs), 35 crianças com menos de 5 anos de idade (27 ACAs e 8 ACCs) e 16 crianças de 5 a 18 anos de idade (6 ACAs e 10 ACCs). Nossos resultados mostram que POD-1 e BUB1B tem valor diferencial em ACT adulto e que a expressão combinada de POD-1 e BUB1B pode ser um marcador de prognóstico em pacientes com carcinoma adulto. Enquanto que, a expressão combinada de POD-1 e SF-1 pode ter valor de diagnóstico em pacientes pediátricos com menos de 5 anos. Em resumo, concluímos que estudos experimentais devem ser realizados para comprovar a relação entre os genes estudados, para que os resultados sejam sólidos o suficiente para serem utilizados no diagnóstico e prognóstico dos tumores adrenocorticais. / The adrenocortical masses are mostly (70-80%) adrenocortical adenomas (ACA). Adrenocortical carcinomas (ACC) are scarce and have limited prognosis, with an incidence of 1-2 cases per million and high recurrence rate (70-80%). Despite adrenocortical tumors (ACT) are rare in Brazil the incidence of these tumors in children is about 10 times higher than the rest of the world, due to a mutation of the TP53 gene. Currently, the diagnosis of adrenocortical mass is carried through Weiss criteria that have limitations, so it is intensive the search for new molecular markers that facilitate the diagnostic of ACTs. TCF21/POD-1 is a transcription factor helix-loop-helix type expressed in mesenchymal-epithelial sites of interaction during embryonic development. In ACTs, POD-1 regulates the expression of endogenous SF-1 through binding the E-box sequence of SF-1 promoter region, and seems to be negatively relates with cell cycle regulatory genes such as BUB1B. BUB1B is a gene encoding a kinase-with important function during mitotic checkpoint. The expression of BUB1B is considered a prognostic factor in different types of tumors, including ACTs. Combined expression of BUB1B and PINK1 (&#916;CtBUB1B - &#916;CtPINK1) has been shown to be a good marker of survival in adults with ACC, whereas the PINK1 expression is reduced in the most aggressive ACC. We hypothesized that the POD-1 expression may have differential value in the diagnosis of adrenocortical masses, and that the analysis of the combined expression of POD-1, BUB1B and PINK1 may have differential value for the prognosis of patients with ACT. In this work were analyzed by PCRq Taqman probes the cDNA obtained from 130 tumor samples: 79 adults (44 ACAs and 35 ACCs), 35 children under 5 years old (27 ACAs and 8 ACCs) and 16 children 5-18 years of age (6 ACAs and 10 ACCs). Our results show that POD-1 and BUB1B has differential value in adult ACT, and the combined expression of POD-1 and BUB1B may have a prognostic value in patients with adult carcinoma. In addition, the combined expression of POD-1 and SF-1 might have diagnostic value in pediatric patients younger than 5 years. In summary, we conclude that experimental studies should be conducted to confirm the relationship between the genes studied, so that the results are solid enough to be used in the diagnosis and prognosis of adrenocortical tumors.

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