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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.
211

Desenvolvimento de uma camara de extrapolacao como instrumento de referencia para dosimetria de radiacao beta

DIAS, SIMONE K. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:40:46Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:07Z (GMT). No. of bitstreams: 1 02805.pdf: 10911213 bytes, checksum: e5c497dd97a5ca4b85e4eb20a6347cd2 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
212

Desenvolvimento e aplicacao de metodologia de feixes terapeuticos de raios x com sistema Tandem

SARTORIS, CARLA E. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:39Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:11Z (GMT). No. of bitstreams: 1 07166.pdf: 3329418 bytes, checksum: 88c4b97cfccfc432748bf428347c8e76 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
213

Implantação do novo protocolo de dosimetria da AIEA no LCI/IPEN/CNEN

SIQUEIRA, PATRICIA M. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:52:05Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:44Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
214

Aceite, comissionamento e controle de qualidade em radiocirurgia / Acceptance, commissioning and quality control in radiosurgery

TORETI, DALILA L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:19Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
215

Etude du devenir atmosphérique de composés organiques volatils biogéniques : réactions avec OH, O3 et NO2 / Study of the atmospheric fate biogenic volatile organic compounds : reactions with OH, O3 and NO2

Bernard, François 11 December 2009 (has links)
L’objectif de ce travail était de contribuer à une meilleure compréhension du devenir atmosphérique des Composés Organiques Volatils d’origine Biogénique (COVB), émis par la végétation. La dégradation d’une série de COVB (myrcène, ocimène, a-farnesène, linalool, 6-méthyl-5-heptène-2-ol et 3-méthyl-1-pentène-3-ol), par les oxydants atmosphériques (OH, O3 et NO2), a été étudiée en utilisant différentes installations expérimentales (chambres de simulation atmosphérique et réacteur à écoulement à aérosol). Les paramètres cinétiques et mécanistiques qui ont été obtenus pour l’ensemble des réactions étudiées ont permis d’estimer les durées de vie atmosphérique des COVB (de quelques minutes à quelques heures). Des produits d’oxydation ont été identifiés et quantifiés, mais le bilan total en carbone en fin de réaction reste incomplet indiquant que d’autres produits sont formés mais non-identifiés. Les rendements de formation des aérosols organiques secondaires (AOS) ont été également mesurés pour les réactions avec OH et O3. L’analyse chimique des AOS (issus de la réaction avec O3) a mis en évidence la présence d’acides dicarboxyliques et de composés oligomères, démontrant l’implication des intermédiaires de Criegee dans la formation des AOS. Le réacteur à écoulement à aérosols, développé dans le cadre de ce travail, a permis de préciser les seuils de nucléation des AOS formés à partir de l’ozonolyse de certains monoterpènes. Enfin, la réactivité des COVB (principalement les diènes conjugués) avec NO2, a été trouvée assez lente et ne représente qu’un puits mineur de ces composés dans l’atmosphère. Toutefois, la mise en évidence de la formation de HONO comme produit de réaction pourrait rendre l’implication atmosphérique de ce processus non négligeable. Les résultats obtenus ont permis de discuter de l’impact de la dégradation de ces COVB dans l’atmosphère. / The aim of this work was to contribute to a better understanding of the atmospheric fate of Biogenic Volatil Organic Compounds, emitted by vegetation. The degradation of a series of BVOC (myrcene, ocimene, a-farnesene, linalool, 6-methyl-5-heptene-2-ol and 3-methyl-1-pentene-3-ol) through reactions with atmospheric oxidants (OH, O3 and NO2) has been investigated using different experimental facilities (atmospheric simulation chambers and aerosol flow tube). First, atmospheric lifetimes of these BVOCs were determined and found varying from few minutes to hours. In addition, gas phase oxidation products were identified and quantified. However carbon budget is still incomplete, indicating that others products are formed but remain unidentified. Secondary organic aerosol yield were also measured in the reactions of the studied BVOCs with OH and O3. Chemical analysis of SOA (from O3 reaction) showed the presence of dicarboxylic acids and oligomer compounds, indicating the possible involvement of the Criegee intermediate in the SOA formation. The new aerosol flow tube, developed in this work, allowed to precise nucleation threshold of SOA formed from the ozonolysis of series of monoterpenes. The reactivity of BVOC (conjugated dienes mainly) with NO2, is found to be slow process, hence, representing only a minor sink for these compounds in the atmosphere. However, the identification of HONO as a reaction product may indicate that this process could be of importance as OH radical source in the atmosphere under certain conditions. The results obtained allowed to discuss the impact of the degradation of these BVOC in the atmosphere.
216

Coupled Large Eddy Simulations of combustion chamber-turbine interactions / Simulations aux Grandes Echelles couplées des interactions chambre de combustion-turbine

Papadogiannis, Dimitrios 06 May 2015 (has links)
Les turbines à gaz modernes deviennent de plus en plus compactes, ce qui augmente les interactions entre leurs différents composants. Les interactions chambre de combustion-turbine sont particulièrement critiques car elles peuvent changer le champ aérothermique dans la turbine et réduire la durée de vie du moteur. Aujourd’hui, ces deux composants sont traités de façon indépendante, ce qui ne permet pas de prendre en compte leurs interactions. Cette thèse propose une approche couplée, basée sur les Simulations aux Grandes Échelles (SGE), une technique qui permet de prendre en compte toutes les interactions chambre de combustion-turbine. Dans la première partie de cette thèse, une méthode, compatible avec le code SGE AVBP, est proposée pour traiter les configurations rotor/stator de manière rigoureuse. Une série de cas test académiques vient prouver que l’interface respecte les propriétés des schémas numériques du code. Cette étude est suivie par une validation de l’approche dans le cas d'une turbine haute-pression mono-étage. Les résultats sont comparés avec des mesures expérimentales et l’influence des différents paramètres et modèles est établi. La deuxième partie de cette travail est dédiée à la prédiction des interactions chambre de combustion-turbine en utilisant les méthodes précédemment décrites et validées. Le premier type d’interaction étudié est la génération du bruit de combustion indirect dans une turbine haute pression. Ce bruit est créé lorsque des hétérogénéités de température, générées dans la chambre de combustion, sont accélérées dans la turbine. Pour simplifier les calculs, les hétérogénéités sont modélisées par des fluctuations de température sinusoïdales, injectées dans la turbine par les conditions limites. Les mécanismes de génération de bruit sont mis en évidence et le bruit de combustion indirect est mesuré et comparé avec une théorie analytique et des prédictions 2D. La deuxième application est un calcul couplé chambre de combustion-turbine qui analyse les interactions entre ces deux composants d’un point de vue aérothermique. Les caractéristiques instationnaires de l’écoulement à l’entrée de la turbine et la migration des hétérogénéités de température dans la turbine sont étudiées. Un calcul de la turbine seule est aussi effectué pour comparaison avec le calcul couplé. / Modern gas turbines are characterized by compact designs that enhance the interactions between its different components. Combustion chamber-turbine interactions, in particular, are critical as they may alter the aerothermal flow field of the turbine which can drastically impact the engine life duration. Current state-of-the-art treats these two components in a decoupled way and does not take into account their interactions. This dissertation proposes a coupled approach based on the high-fidelity Large Eddy Simulation (LES) formalism that can take into account all the potential paths of interactions between components. In the first part of this work, an overset grid method is proposed to treat rotor/stator configurations in a rigorous fashion that is compatible with the LES solver AVBP. This interface treatment is shown not to impact the characteristics of the numerical schemes on a series of academic test cases of varying complexity. The approach is then validated on a realistic high-pressure turbine stage. The results are compared against experimental measurements and the influence of different modeling and simulation parameters is evaluated. The second part of this work is dedicated to the prediction of combustion chamber-turbine interactions using the developed methodologies. The first type of interactions evaluated is the indirect combustion noise generation across a high-pressure turbine stage. This noise arises when combustor-generated temperature heterogeneities are accelerated in the turbine. To simplify the simulations the heterogeneities are modeled by sinusoidal temperature fluctuations injected in the turbine through the boundary conditions. The noise generation mechanisms are revealed by such LES and the indirect combustion noise is measured and compared to an analytical theory and 2D predictions. The second application is a fully-coupled combustor-turbine simulation that investigates the interactions between the two components from an aerothermal point of view. The rich flow characteristics at the turbine inlet, issued by the unsteady combustion in the chamber, are analyzed along with the migration of the temperature heterogeneities. A standalone turbine simulation serves as a benchmark to compare the impact of the fully coupled approach.
217

Estudo da remodelação cardíaca em pacientes com doença pulmonar obstrutiva crônica

Coleta, Karina Dela [UNESP] 26 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-26Bitstream added on 2014-06-13T21:03:38Z : No. of bitstreams: 1 coleta_kd_dr_botfm.pdf: 391595 bytes, checksum: dde69b55ebd37c6d547a6c2e6321775d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Pacientes com doença pulmonar obstrutiva crônica (DPOC) apresentam risco elevado para eventos cardiovasculares. Entretanto, existem poucos estudos sobre a função do ventrículo esquerdo (VE) nesses pacientes e os resultados são controversos. Os objetivos deste estudo foram: analisar a estrutura e função do ventrículo direito (VD) e câmaras cardíacas esquerdas, por meio de Dopplerecocardiografia, em pacientes com DPOC e avaliar a associação entre as variáveis ecocardiográficas e as variáveis clínicas relevantes. Foram avaliados 45 pacientes com DPOC (idade: 65,8 ± 10,6 anos, 64% homens): 17 pacientes com DPOC leve a moderada (grau I e II) provenientes do Serviço de Pneumologia da Faculdade de Medicina de Botucatu (FMB) e 28 pacientes com DPOC muito grave (grau IV) acompanhados no Ambulatório de Oxigenoterapia da FMB. Os critérios de inclusão foram: diagnóstico de DPOC, estabilidade clínica e, para os pacientes com DPOC IV, uso de oxigênio domiciliar por período mínimo de três meses. Para o grupo controle foram selecionados 15 indivíduos saudáveis (idade: 64,3 ± 10,1, 47% homens). Os critérios de exclusão foram: imagem ecocardiográfica inadequada, hipertensão arterial sistêmica, diabetes mellitus, doença coronariana, valvopatias, arritmias, patologias respiratórias associadas ou outras patologias cardíacas. Espirometria pré e pós-broncodilatador e oximetria de pulso foram realizadas por todos os sujeitos da pesquisa e gasometria arterial somente para os pacientes com DPOC... / Chronic obstructive pulmonary disease (COPD) is a strong risk factor for cardiovascular events. However, the status of left ventricle (LV) has been less studied and the results are controversial. The objectives were: to analyse the right ventricle (RV) and the left heart chambers structure and function in COPD patients by echocardiogram, and to analyse the association between echocardiographic variables and the relevant clinical variables. Forty-five COPD patients (age: 65,8 ± 10.6 years; 64% male) were evaluated: 17 mild to moderate COPD patients (grade I and II) and 28 very severe COPD patients (grade IV). The inclusion criteria were: COPD diagnosis, clinical stability and home oxygen therapy for at least three months (very severe COPD). The control group consisted of 15 healthy subjects (age: 64.3 ± 10.1 years; 47% male). Exclusion criteria were: poor quality echocardiographic image, history of systemic hypertension, diabetes mellitus, coronary artery disease, valvular heart disease, arrhythmias, associated lung diseases or other heart diseases. Pre and post-bronchodilator spirometry and pulse oximetry were performed in all subjects and arterial gasometry was performed in COPD patients only... (Complete abstract click electronic access below)
218

Postavení a činnost české lékařské komory / The position and activities of the Czech Medical Chamber

Klůfa, Jaroslav January 2011 (has links)
The topic of this thesis is the position and activities of the Czech Medical Chamber. Its aim is to analyze the role and purpose of this professional chamber in the Czech Republic. I have chosen this particular topic because I mean that although the self- government of professional associations, especially the Czech Medical Chamber, belongs to very important institutes of the legal order of the Czech Republic; the literature addresses this issue only marginally. The next reason for my research is the fact, that just the Czech Medical Chamber is very questionable professional chamber. The thesis is composed of five chapters; each of them describes particular aspects of Czech Medical Chamber (CMC). Chapter One is introductory and is trying to explain the notions self-government and public corporation. The last part of this chapter deals the political, economic and sociological aspects of the CMC. Chapter Two consists of two parts. Part One surveys historical development of the CMC from year 1891, when the Habsburg monarchy issued a law on the establishment of medical chambers, to the present. Part Two look at medical chambers in other countries of Central Europe and endeavours to compare these organizations. Chapter three is subdivided into two parts. Part One focuses on functions of the CMS and...
219

Elaboracao e implementacao de testes de controle de qualidade em equipamentos de angiografia por subtracao digital

LAMMOGLIA, PATRICIA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:46:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:44Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:99/06803-9
220

Desenvolvimento de um sistema de referencia e de uma metodologia para calibracao de aplicadores oftalmicos utilizados em braquiterapia

OLIVEIRA, MERCIA L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:55Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:02:14Z (GMT). No. of bitstreams: 1 10308.pdf: 5951521 bytes, checksum: c3f464af4f9a5b567dacd34287e1566f (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tese (Doutoramento) / IPEN/T / Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP / FAPESP:01/00231-5

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