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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.
81

Všestranné zabezpečení evakuace / All-round indemnity of the evacuation

JAREŠOVÁ, Věra January 2007 (has links)
This graduation thesis has primary target in faithful imagine of basic evacuation steps within all-around idemnity of her ensuring. Today{\crq}s, this topic rise to important theme and we can tell that if is evacuation correct provided than it means the most effective instrument of people safety and create the files of differents measurement as well. Together build one entity of very complicated planning and providing procedures in their individual steps. The document is dividing to fourth sections. First include actual stage and law procedures of evacuation process within Czech Republic area. Second section is devote to 3 evacuation types, namely floods, chemical disaster following by outflow of chemical materials and fires. These are completed by example of flood due to weit disruption. On the base of victims testimony and research by auxiliary investigation with people are discuss closely some answers to basic questions concerning to evacuation. Finaly is described severally steps and subprocesses of evacuation secure. Additional value of this document is in basic information disclosure for readers questions with effort to inform society. Effective and flexible comunication is main and key point of success.
82

Unbiased Spectral Survey towards the intermediate-mass Class 0 protostar Cep E-mm / Étude systématique spectrale vers la protoétoile de classe 0 de masse intermédiaire Cep E-mm

Pacheco-Vazquez, Susana 11 December 2012 (has links)
Les protoétoiles de masse intermédiaire (IM) (2 ≤ M* ≤ 8 Msun) sont le lien entre les étoiles de faible et haute masse car elles couvrent également un intervalle intermédiaire de luminosités, de densités et de températures [Fuente et al., 2012]. Même si les « IM-YSOs » jouent un rôle important dans l'étude de la formation des étoiles, on a très peu de connaissances sur la formation et l'évolution des premières étapes des protoétoiles de masse intermédiaire. Les études systématiques spectrales sont un outil puissant pour caractériser la composition chimique d'un objet astrophysique, et la seule façon d'obtenir un recensement complet des espèces chimiques. Une étude spectrale fournit également des lignes multiples de la même molécule, donnant la possibilité d'une analyse multifréquences ainsi que d'une modélisation. En outre, grâce aux profils des raies, nous pouvons obtenir des informations sur la cinématique, et identifier les structures au long de la ligne de vue, en tant que sources multiples, des jets ou des cavités, par exemple, [Caux et al., 2011]. Les phénomènes d'éjection (jets, des vents et des « outflows » bipolaires moléculaires), sont une phase inhérente au processus de formation d'étoiles observées dans les YSOs de toutes masses dans des longueurs d'onde millimétriques. Cependant, il n'y a pas d'études systématiques dans l'intervalle de masse intermédiaire comme dans le cas des protoétoiles de faible et haute masse. Compte tenu de l'absence d'une étude systématique de la partie mm/submillimétrique dans le spectre des protoétoiles de masse intermédiaire, au cours de ma thèse, j'ai mené une étude systématique spectrale vers la protoétoile de masse intermédiaire de classe 0 Cep E et de son « outflow » moléculaire. / Intermediate-mass (IM) protostars (2 ≤ M∗ ≤8 Msun) are the link between low and the high mass stars as they cover also an intermediate range of luminosities, densities and temperatures [Fuente et al., 2012]. Even though the IM-YSOs are important in the study of star formation, very little is known about the formation and first evolutionary stages of IM protostars. Unbiased spectral surveys are a powerful tool to characterize the chemical composition of an astrophysical object, and the only way to obtain a complete census of the chemical species. A spectral survey provides also multiple lines from the same molecule, giving the possibility of a multi-frequency analysis and modeling. Also, through line profiles, we can obtain kinematic information, and identify structures along the line of sight, as multiple sources, outflows, jets or cavities, e.g. [Caux et al., 2011]. The outflow phenomena (jets, winds and bipolar molecular outflows), are an inherent phase in the process of star formation observed in YSOs of all range of masses at millimeter wavelengths. However, there are not systematic studies in IM range as in the case of of low- and high-mass protostars. Given the lack of a systematic study of the mm/submm spectrum of IM protostars, during my thesis I carried out an unbiased spectral survey towards IM Class 0 Cep E protostar and its molecular outflow.
83

Inclusão do controle de deflúvio em modelos de gestão florestal: um estudo no vale do Paraíba - SP. / Inclusion of water outflow control in forest management models: a study case in vale do Paraíba – SP.

Tatiana Mahalem do Amaral 12 April 2002 (has links)
Baseado em uma relação simples entre volume de madeira em pé e deflúvio observados em duas microbacias com povoamentos de eucaliptos, este estudo compara os resultado obtido por três modelos de programação linear: (i) um que maximiza o valor total do projeto, com restrições de área e de produção de madeira; e (ii) dois outros modelos que fazem o mesmo com o controle do indicador hidrológico (deflúvio). A hipótese principal do trabalho é que a consideração do indicador hidrológico no planejamento de povoamentos florestais afeta significativamente os regimes de manejo, alterando os planos de colheita e o fluxo de produção de madeira. A área de estudo é constituída por trinta e cinco unidades de gestão, com áreas que variam de 30 ha a 800 ha e diferentes produtividades, totalizando 8007 ha. Regimes de talhadia simples, baseados em dois cortes, diferem entre si apenas pela idade em que a floresta é cortada. O nível de deflúvio e o volume de madeira em pé foram estatisticamente ajustados utilizando um modelo exponencial baseado na coleta de dados na área de estudo. O resultado da relação entre deflúvio e estoque de madeira mostra uma curva que é convexa em relação a origem e negativamente inclinada. Como as áreas de corte raso e florestas novas produzem fluxos de deflúvio elevados, a regularização do mesmo foi incluída como restrição no modelo. Os resultados obtidos permitem concluir que a inclusão das restrições hidrológicas no modelo afetou o manejo, alterou o fluxo de produção de madeira e resultou em valores presente líquidos globais diferentes para cada modelo, confirmando então a principal hipótese do trabalho. A água e a madeira são dois recursos de grande importância e devem ser controlados simultaneamente. As técnicas de programação linear se mostraram eficientes para gerir o manejo desses recursos. / Based on a simple relationship between growing stock and water outflow observed on two watersheds planted with Eucalyptus in Brazil, this study compares the results obtained by three different linear programming formulations: (i) one that maximizes the net present value simply constrained by area and a regulated wood production flow; and (ii) two other models that maximize the net present value constrained by area, a regulated wood production flow, and specific hydrological goals. As one of the hypothesis, it is stated that the inclusion of hydrological constraints in the model will affect significantly the selection of forest regimes, altering the final harvest-scheduling plan and the wood production flow. Thirty-five management units, with areas ranging from 30 ha to 800 ha and different site indexes, form an Eucalyptus plantation project with 8.007 hectares. Simple coppice regimes, based on two clear cuts followed by the complete renewal of the plantation, differ one to another only by the age at which the clear cut is scheduled. Water outflow levels and stock volume levels were statistically adjusted according to an exponential model based on data collected on watersheds in the study area. The resulting relationship between outflow and stock volume shows a curve that is convex to the origin and negatively sloped. Given that clear-cut areas produce highly undesirable water outflows to the watershed, maximum water outflow limits had to be included as constraints in the model. Results obtained by the hydrologically constrained model confirm the hypothesis that the wood production flow is affected by limiting water outflow. The study allowed the attribution of economical values to different levels of limitations in terms of total water production in the watershed. Water and wood, two of the most important assets to a forester, should be managed together. Linear programming modeling techniques, proved to be very efficient when managing such resources.
84

Pacientes com cardiomiopatia hipertrófica obstrutiva tratados com redução septal percutânea. Análise da evolução tardia / Patients with hypertrophic obstructive cardiomyopathy treated with percutaneous septal reduction. Analysis of late outcome

Silvia Judith Fortunato de Cano 12 August 2014 (has links)
Introdução: O tratamento alternativo de Redução septal percutânea (RSP) em pacientes com cardiomiopatia hipertrófica obstrutiva é relativamente novo e há poucos trabalhos publicados sobre a evolução tardia. Objetivos: Avaliar nos pacientes com cardiomiopatia hipertrófica obstrutiva sintomáticos e refratários ao tratamento clínico, tratados com RSP, a sobrevida cardíaca e global, qualidade de vida, eventos maiores e as alterações encontradas no eletrocardiograma (ECG), ecocardiograma(ECO) e Holter 24h antes e na evolução tardia de até 15 anos. Método: Foram incluídos pacientes consecutivos que realizaram RSP no Instituto Dante Pazzanese de Cardiologia e no Hospital do Coração de Outubro de 1998 até junho de 2013. Todos os pacientes realizaram exame clínico, ECG e ECO, e a maioria Holter 24h e responderam o questionário DASI antes e pós-RSP. Os dados qualitativos foram descritos em frequências absolutas e relativas e os quantitativos resumidos em médias ± desvios padrão. Para as variáveis quantitativas foram utilizados modelos ANOVA com medidas repetidas, seguidos pelo método de comparações múltiplas de Bonferroni. O nível de significância de 0,05 foi aceito. Resultados: Dos 56 pacientes incluidos, 28 (50%) eram homens, a idade média foi 53,2 ±15,5 anos sendo 2 crianças e 11 (19,6%) tinham coronariopatia. A maioria estava em classe funcional III-IV, o gradiente médio basal por ECO foi 92,8 ± 3,3 mmHg, a espessura do septo 23,9 ± 0,6 e 62,5% tinha insuficiência mitral (IM) moderada. Durante a internação 1 (1,7%)paciente implantou marcapasso. Durante o seguimento de 7,4 ± 4 anos ocorreram 3 implantes de CDI, 2 por prevenção secundaria e 1 marcapasso, 1 nova RSP, 3 cirurgias de miectomias e houve 7 (12,5%) óbitos, apenas 2 de causa cardíaca. O tempo médio de sobrevida, estimado pelo método de Kaplan Meier foi de 13,3 anos (IC95% 12,2 a 14,5 anos), com expectativa de sobrevida de 96,4% em 1 ano, 87,7% em 5 anos e 81,0% a os 12 anos pós-RSP. Houve melhora significativa na qualidade de vida pelo questionário DASI e na classe funcional da NYHA que passou de 3,6 ± 0,5 para 1,2 ± 0,5 no pós-RSP. Na última avaliação do ECO o gradiente 9,37 ± 6,7 mmHg, o septo 12,87 ± 0,98 mm e a IM foi discreta em 90% todos com p < 0,001. Das variáveis analisadas somente o gradiente no estresse, p=0,039 e a massa p=0,024 foram associados a pior prognóstico. Conclusões: A redução septal percutânea mostrou, na evolução tardia com 100% de seguimento, ser uma técnica segura, eficaz em manter os benefícios tardiamente com baixa mortalidade, oferecendo melhora significativa da classe funcional e da qualidade de vida para os pacientes. / Introduction: Percutaneous septal Reduction (PSR) is a relatively new alternative treatment in patients with obstructive hypertrophic cardiomyopathy and there are few published studies on late evolution. Objectives: Evaluate in symptomatic patients with hypertrophic obstructive cardiomyopathy refractory to medical treatment and who underwent PSR, cardiac and overall survival, quality of life, major events and changes found on the electrocardiogram (ECG), echocardiography (ECHO) and Holter 24h before and after PSR during an evolution up to 15 years. Method: Consecutive patients who were submitted to RSP in Dante Pazzanese Institute of Cardiology and Heart Hospital from October 1998 were included. All patients went through clinical, ECG and ECHO examination, and nearly all answered DASI questionnaire, 24-hour Holter monitoring before and after PSR. Qualitative data were described as absolute and relative frequencies and quantitative summarized as means ± standard deviations. ANOVA models were used for quantitative variables with repeated measures, followed by Bonferroni method for multiple comparison. Significance level of 0.05 was accepted. Results: From 56 patients included, 28 (50%) were men , the mean age was 53.2 ± 15.5 years with 2 children and 11 (19.6%) had coronary artery disease . Most were in functional class III - IV from NYHA, the mean baseline ECO gradient was 92.8 ± 3.3 mmHg, the septal thickness 23.9 ± 0.6mm and 62.5 % had moderate mitral regurgitation (MR). During hospitalization 1 (1.7%) patient required permanent pacemaker. During follow-up of 7.4 ± 4 years, 3 patient required ICD implantation, 2 (for secondary prevention), 1 permanent pacemaker, 1 new RSP, 3 myectomy surgery. There were 7 (12.5%) deaths but only 2 of cardiac causes. The median survival time estimated by the Kaplan Meier was 13.3 years (95% CI 12.2 to 14.5 years), with expected survival of 96.4% at 1 year, 87.7% at 5 years and 81.0% at 12 years post-PSR. Significant improvement was seen in quality of life inferred by DASI questionnaire answers and NYHA functional class from 3.6 ± 0.5 to 1.2 ± 0.5. In last evaluation we found statistical significant reduction in ECO gradient 9.37 ± 6.7 mmHg, septum thikness 12.87 ± 0.98 mm and MR was mild in 90 % of patients. Of the variables analyzed only stress gradient (p = 0.039) and mass (p = 0.024) were associated with worse prognosis. Conclusions: The results of this study suggest that percutaneous septal reduction in late evolution with no loses in follow-up, is a safe technique, effective in reducing ventricular gradient and preserving the benefits in long-term evolution with low mortality, offering significant improvement in functional class and quality of life for patients.
85

Associação da variabilidade climática dos oceanos com a vazão de rios da Região Norte do Brasil / Association of climatic variability of the oceans with the outflow of rivers in Northern Brazil

Elaine Rosangela Leutwiler di Giacomo Silva 17 May 2013 (has links)
O objetivo desta pesquisa foi investigar a relação linear existente entre a Temperatura de Superfície do Mar (TSM) dos oceanos Pacífico e Atlântico e a vazão do rio Madeira, localizado na parte sul da região Norte do Brasil. A investigação foi feita nas escalas mensal, sazonal e anual, para o período de 1968 a 2009. A hipótese de que alterações climáticas na região Norte do Brasil estariam associadas a episódios de aquecimento e resfriamento dos oceanos globais, já que quando ocorrem têm o potencial de modificar o padrão de precipitação em áreas remotas do globo, foi a motivação central da pesquisa. A pesquisa foi desenvolvida com base em análises estatísticas para os dados de TSM, índices climáticos e a vazão do rio Madeira. Observou-se que a vazão mensal do rio Madeira apresenta correlação linear significativa com áreas específicas dos oceanos Atlântico e Pacífico. No Oceano Atlântico Norte, são significativas as correlações obtidas nos setores tropical (área AT3) e norte (área AT1). O setor subtropical do Atlântico Norte (AT2) apresenta correlações lineares não tão expressivas como suas áreas tropical e norte. O Atlântico Sul não apresenta áreas com correlações lineares significativas com a vazão. As áreas com correlação significativa do Atlântico Norte (AT1) apresentam valores negativos máximos entre -0,6 e -0,4. Os valores de correlação linear entre a vazão mensal do rio Madeira e a TSM do Atlântico (AT2) apresentam um pequeno aumento para os cálculos realizados com defasagem temporal de até nove meses, entre 0,3 a 0,4 para 5 meses de defasagem entre a vazão e a TSM. A TSM do setor oeste do Pacífico tropical apresenta fortes valores negativos de correlação linear com a vazão do rio Madeira, com valores máximos que variam entre -0,7 e -0,4. Tal qual acontece para o Atlântico, as águas superficiais do Pacífico tropical oeste apresentam um pequeno aumento dos valores de correlação linear para defasagens maiores entre a TSM e a vazão. As áreas com forte correlação negativa no setor oeste do Pacífico tropical foram denominadas PA1, no norte, e PA3, no sul. Uma pequena área com correlação significativa e positiva a leste da bacia do Pacífico, junto à costa do Chile, foi denominada PA2. Nesta área os valores máximos de correlação linear entre a vazão mensal e a TSM variam entre 0,2 e 0,4. A análise de correlação linear entre a vazão anual do rio Madeira e índices climáticos indicam que os índices ODP, MEI e OAN são os mais bem correlacionados com a vazão, apresentando valores iguais a 0,89, 0,86 e 0,85, respectivamente. Com base na TSM das áreas bem correlacionadas com a vazão do rio Madeira e nos índices climáticos considerados, foi desenvolvido um modelo estocástico de regressão linear múltipla para a previsão da vazão trimestral com antecedência de um trimestre. A TSM das áreas do setor oeste do Pacífico tropical, PA1, e do Atlântico Norte tropical, AT3, constituíram as variáveis selecionadas para a elaboração do modelo estocástico. O modelo estocástico foi desenvolvido para o início da série temporal considerada, de 1968 a 1988, e apresentou um ajuste linear com coeficiente de determinação igual a 78%. A verificação do modelo foi feita para o final da série, de 1989 a 2009. O erro médio normalizado calculado pela diferença entre os valores de vazão previstos pelo modelo e os observados foi igual a 40%. Desta forma, conclui-se que a vazão trimestral do setor sul da região Norte do Brasil é uma variável que pode ser prevista com base na variabilidade da temperatura das águas superficiais dos oceanos Pacífico e Atlântico. A análise do comportamento atmosférico com base em períodos específicos de anomalias de TSM no Atlântico Norte tropical indica que a ocorrência de TSMs mais altas (baixas) que o normal foram acompanhadas por ventos de leste mais fracos (fortes). Foram analisados os campos atmosféricos médios para os meses chuvosos de novembro a março para as variáveis Velocidade Vertical (Omega) em 500 e 850 hPa, divergência e vorticidade do vento. Os resultados obtidos demonstram que em média, a variabilidade atmosférica foi determinante no que se refere às anomalias apresentadas pela vazão. / The objective of this research was to investigate the linear relation between the sea surface temperature (SST) over Pacific and Atlantic oceans and the outflow of the Madeira river, located at the southern part of the Northern region of Brazil. The investigation considered monthly, seasonal and annual scales, to the period between 1968 to 2009. The consideration about the influence of heating and cooling of oceanic areas over climate around the world constitutes the main hypothesis taken in account in the study. The research was developed based on statistical analysis considering SST, climatic indexes and river outflow data. The monthly outflow for Madeira River shows significant linear correlation to SST at specific areas over Atlantic and Pacific. Over North Atlantic, the linear correlation values are significant at the tropical and north sectors, namely AT3 and AT1, respectively. The subtropical sector of North Atlantic presents positive correlation but not too expressive as the tropical and north areas of Atlantic. South Atlantic does not present significant values of linear correlation with the river outflow. The area with significant correlation over North Atlantic (AT1) presents maximum negative values ranging between -0,6 and -0,4. In general, the greater the interval between river outflow and SST data, greater is the linear correlation values. SST data from the western sector of tropical Pacific presents strong negative correlation with Madeira River outflow data, and shows maximum values ranging between -0,7 and -0,4. The areas to the West of Pacific showing high negative correlation were named PA1 and PA3, to northern and southern sectors, respectively. A small area that shows significant positive linear correlation to the river outflow data, PA2, is located over the eastern side of Pacific basin, very closed to the coast of Chile. In this area, the linear maximum correlation values range between 0,2 and 0,4. Linear correlation analysis between annual river outflow data and climatic indices indicates that PDO, MEI and NAO are those more correlated with the river outflow data, presenting values equal to 0,89, 0,86 e 0,85, respectively. Based on averaged SST and climatic indices well correlated to the Madeira River outflow data, a stochastic model was developed in order to forecast the river outflow in seasonal scale. SST from west of tropical Pacific, PA1, and from tropical North Atlantic, AT3, were selected to build up the stochastic model. The stochastic model was developed considering the first half of the total series, between 1968 and 1988, while the last period was used to validate the model, between 1989 and 2009. The linear adjusting over the first period reach a determining coefficient equal to 78% and the normalized mean error obtained for the second period was equal to 40%. Thus, we conclude that the seasonal outflow for Madeira River is a climatic variable that can be forecast based on the SST variability over specific areas on Pacific and Atlantic oceans. The analysis of atmospheric behavior based on specific periods of SST anomalies in the tropical North Atlantic indicates that the occurrence of SSTs higher (lower) than normal was accompanied by easterly winds weak (strong). We analyzed the average atmospheric fields for the rainy months from November to March for variables Vertical Speed (Omega) at 500 and 850 hPa, divergence and vorticity of the wind. The results show that approximately the atmospheric variability was decisive with regard to the deficiencies presented by the ouflow.
86

Navazující opatření na vodohospodářské řešení vodní nádrže Těšetice / Follow-up measures for the water management solution of the Těšetice water reservoir

Žiaček, Tomáš January 2019 (has links)
The main aim of the thesis was the liquefaction of Únanovka streamflow under the Těšetice dam with the focus on suitable flood protection of the villages of Těšetice, Bantice and Práče.The thesis evaluates the existing condition of the Únanovka streamflow in the river mileage 1.6593 – 6.4103. Calculation of the streamflow capacity was carried out per 1D mathematical model in the HEC-RAS programme for the selected N-year flow from the ČHMÚ hydrological study. Final value of the improved drainage from the dam was determined together with the possible value of water collection. Within the thesis the hydro-ecological monitoring of the watercourse was carried out (HEM analysis 2014).
87

Návaznost ÚSES na prvky protierozní a protipovodňové ochrany v KPÚ / Teritorial system of ecological stability consistent to erosion control and flood protection in land consolidation

Strádalová, Lucie January 2013 (has links)
This thesis evaluates the elements of the Territorial system of stability, which were designed within the plan of the common facilities of comprehensive landscaping, with regards to the elements of the erosion and flood protection. Within the scope of this work there was proceeded the hydrological analysis on the parts of the watersheds of the specific cadastral territories of Lichnov and Šardice. esign of the ÚSES´s elements within the KPÚ at specific cadastral territories was further evaluated in terms of area of the individual elements anEcological stability the change after the design of these elements.
88

Hydrological and Paleoclimate Analysis of a Pinyon-Juniper and Fen-Dominated Watershed on the Windy Ridge Mega-Landslide

Barker, Joel Frederick 01 November 2019 (has links)
Water BudgetThis chapter documents the hydrologic analysis of a watershed within the Windy Ridge mega-landslide of Central Utah to (1) create a water budget and (2) place a quantitative limit on the magnitude of climatic changes documented by Shurtliff et al. (2017) and Hudson et al. (2019). (1) A water budget was calculated over the last four years using instrumentation and weather stations both within and surrounding the watershed, In terms of precipitation input, 85% is released by the evapotranspiration of the Pinyon-Juniper forest, 4% discharges as surface water from the base of the watershed, and 11 % infiltrates the groundwater system. This infiltration rate is slightly lower than the 15% suggested by Maxey-Eakin method (Maxey and Eakin, 1949), likely due to the less permeable, clay-rich sediment. (2) Previous studies performed on Garden Basin Cattail (GBC) Fen at the base of its watershed suggest swings from pond-like to wetland environments (Shurtliff et al, 2017; Hudson et al, 2019). This study estimated precipitation values necessary to create standing water (pond) environments. Changes in annual precipitation, as well as input from North American monsoon (NAM), may cause these environmental changes. Each of these cases were examined. Trends in piezometer measurements compared to mean annual precipitation indicated that ‰¥ 644 mm of annual precipitation are required to sustain a wet (perennial standing water) environment. The change from wetland to pond conditions may depend on seasonal trends in precipitation. This study suggests an increase of 150-300 mm of precipitation in late summer (NAM) may be connected to perennially wet conditions. The higher annual precipitation values, largely accomplished by NAM fluctuations, caused a transition from wetland to pond (Hudson et al., 2019; Shurtliff et al., 2017). Chapter 2: Core AnalysisChapter 2 further documents the watershed's historical environmental and climate record by analyzing sediment and topography surrounding GBC fen, adding to the works of Shurtliff et al. (2019) and Hudson et al. (2019). A core was extracted from GBC fen at the base of the watershed and the sediment analyzed in terms of color, texture, environmental scanning electron microscope (ESEM) imaging, RockEval pyrolysis, and 14C ages. These results were then compared to pre-existing pollen and diatom proxies completed on a previous core by Shurtliff et al. (2019). This study suggests climatic variation, along with basin fill processes, was the driver of environmental change in GBC fen (Garden Basin watershed). Climate proxies show the basic trend from a particularly wet period (12-9 ka BP) of more stagnant or deeper water, to a much dryer period of much shallower water levels (9-3 ka BP), followed by a rebound in moisture levels, especially in the past few hundred years. Although climate was the driver of transitions within GBC2 core, a pollen record of sustained shallow water plants and MASW (Park et al., 1999) survey may suggest beaver activity.
89

Non-Contrast-Enhanced Magnetic Resonance Venography using Magnetization-Prepared Rapid Gradient-Echo in the Preoperative Evaluation of Living Liver Donor Candidates: Comparison with Conventional Computed Tomography Venography / MPRAGE法を用いた非造影MR Venographyによる生体肝移植ドナー候補者の術前評価:従来法であるCT Venographyとの比較

Yamashita, Rikiya 23 May 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20564号 / 医博第4249号 / 新制||医||1022(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 増永 慎一郎, 教授 妹尾 浩, 教授 鈴木 実 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
90

Performance of Supersonic Turbomachinery for Rotating Detonation Engines

Ford Heston Lynch (14637695) 28 July 2023 (has links)
<p>      Rotating detonation combustion has been investigated since the 1960s and has gained much attention in the past decade due to its promise of pressure gain. In theory, the pressure gain can provide higher power output at inlet total temperatures similar to those of Brayton cycle engines, leading to increased efficiency and decreased engine size. However, complexities presented by detonative combustion have prevented it from becoming widely adopted, especially for turbomachinery applications. A rotating detonation combustor with a transonic or supersonic exhaust imposes rapid fluctuations in pressure, temperature, and flow angle at the inlet of the turbine. To account for these fluctuations, ad hoc turbine designs have been proposed over the last few years, including supersonic bladed and bladeless variants. Computational fluid dynamics simulations have shown that it is possible to extract a meaningful amount of work from these turbines, but dedicated experimental test rigs are needed to validate these designs at relevant conditions in long-duration tests.</p> <p>     Toward this goal, this thesis focuses on three research elements. The first element is the design of a cooled rotating detonation combustor with a downstream turbine that can operate for long durations. The cooled combustor is accomplished in a two-part procedure: (1) repurposing Purdue University’s Turbine-integrated High-pressure Optical Rotating detonation engine (THOR) and (2) designing a lightweight, gaseous film-cooled combustor shroud with ample configurations for pressure, temperature, and optical measurements.</p> <p>     The second element is the design of three supersonic turbines for use in RDEs: an axial-flow bladed turbine, an axial-flow bladeless turbine, and an axial-inflow/radial-outflow bladed turbine. Each turbine is designed for cold flow testing, and provisions for mounting the axial-flow bladed turbine downstream of the cooled combustor are proposed. Supplemental turbine hardware is also designed to provide precise and repeatable conditions for the turbine tests.</p> <p>     The third element is the construction of an energy absorption dynamometer to measure the power output of the different supersonic turbines. Four types of dynamometers are explored, including hydraulic brakes, electromagnetic brakes, electric generator brakes, and airbrakes. Although the literature declares the electromagnetic brake to be more accurate, the most cost-effective solution is to utilize the compressor side of a donated turbocharger. Combining all research elements yields a new test rig for this new class of supersonic turbines.</p>

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