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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.
311

Étude des pertes atypiques dans les machines synchrones à aimants à hautes performances pour applications aéronautiques / Study of atypical losses in high performance permanent-magnet synchronous machines for aircraft applications

Boubaker, Nadhem 21 July 2016 (has links)
La thèse porte sur la caractérisation expérimentale des pertes singulières dans les matériaux magnétiques au sein d’actionneurs électromécaniques conçus pour le développement du programme « avion plus électrique », où la maîtrise des pertes d’énergie est un enjeu absolument majeur. Ce programme, de portée mondiale, vise, entre autre, à remplacer, dans l’avion, les actionneurs hydrauliques par des actionneurs électromécaniques, quand c’est possible.Par pertes singulières on entend toutes les pertes liées aux contraintes magnéto-mécano-thermiques liées d’une part à la mise en œuvre (découpe, assemblage contraint, isolation, traitement thermique...) des matériaux et d’autre part aux conditions réelles de fonctionnement (champ tournant, haute fréquence, saturations locales...) au sein des machines électriques (HV/HF), et qui sont très difficiles à estimer précisément de façon analytique ou via les dispositifs conventionnels de tests. Ces sollicitations influencent les caractéristiques de tôles qui peuvent s’éloigner significativement des données du fabricant (donc fausser le calcul des performances).Au début de cette thèse on s’est focalisé sur le montage d’un banc d’essai évolutif équipé de moyens de mesure directe du couple et d’une machine d’entraînement (8 ktr/min ; 42 kW) tarée par nos soins. Sur cette dernière une longue campagne d’essais a été menée pour isoler les différentes composantes de pertes, dont, par exemple, les pertes mécaniques (par frottement dans les roulements + aérodynamiques) qui ont été quantifiées via un rotor neutre. Les pertes dans les aimants sont indissociables des pertes fer, donc, elles ont été estimées par le biais d’une modélisation par éléments finis tridimensionnelle. Les pertes dans la frette de maintien sont nulles du fait qu’elle est isolante (thermo-rétractable). Le bobinage utilisé dans ce moteur est très particulier, à barres massives (remplissage de cuivre dans l’encoche jusqu’à 90%), développé dans notre laboratoire IES. Les pertes atypiques au sein de ce bobinage spécial ont été profondément abordées dans ces travaux (effet de refoulement de courants, pertes aux extrémités de la machine...).Dans la dernière partie de cette thèse, nous avons exploré le fonctionnement des machines synchrones à aimants à haute fréquence afin d’accroître la densité de puissance de nos moteurs (pour franchir la barre de 2.5 kW/kg). Pour ce faire, après une étude détaillée, nous avons proposé en premier lieu un prototype avec des matériaux standard (stator FeCo Vacodur49 0.2mm, rotor FeSi, aimants NdFeB nuance N35EH, bobinage à barres cuivre) fonctionnant à 1666 Hz, tournant à 5000 tr/min, avec une densité de puissance de 4.5 kW/kg et un rendement de 94%. En second lieu, nous avons proposé un deuxième prototype de rendement plus faible (93%) mais qui a une densité de puissance proche de 6 kW/kg avec un rotor sans fer et un bobinage en Aluminium.Avant le montage final de ce prototype modulaire, nous avons effectué des mesures de pertes magnétiques, en conditions réelles de fonctionnement d’un moteur électrique, sur une multitude de tôles FeSi et FeCo (Vacodur49, NO20, M270-35A) avec la variation de différents procédés de fabrication: isolation (vernis thermo-collant « back-lack », vernis C5), découpe (laser, électroérosion) et traitement thermique. Pareillement, toutes les pertes mises en jeu ont été séparées (mécaniques, par courants induits dans les viroles...) pour pouvoir remonter aux pertes magnétiques et, donc, enfin, quantifier empiriquement le coefficient de majoration de pertes fer. / The main aim of this thesis was to study and experimentally assess the additional iron losses in the stator (electrical lamination steel) of high performance permanent magnet synchronous machines (PMSM) designed for aircraft applications, in relation with the “more-electric-aircraft” project. This international program consists of gradually introducing electrical systems to replace onboard hydraulic and pneumatic systems, for example to power the landing gear wheels (Electric Green Taxiing System)…The extra iron losses are caused by manufacturing processes (cutting, sticking, insulation, stacking, pressing, shrink-fitting, thermal treatment …) and the real conditions of use of electrical motor (namely: rotational flux, saturation, high frequency…). Indeed, the mechanical and thermal stresses during the manufacturing steps can deteriorate the magnetic properties of the material and significantly increase the iron losses. These aspects are difficult to accurately evaluate by analytical models or standard measurements (Epstein frame…) and require experimental assessment to precisely calculate the motor efficiency.First of all, we started by developing a test bench equipped with drive motor: PMSM 8000 RPM ; 42 kW. For accurate assessment, the losses in this machine are separated on the test bench, for example, the mechanical losses (bearings loss & windage loss) have been measured at different speed with a non-magnetic rotor. Rotor magnets eddy-current losses cannot be isolated from iron losses, for this reason they have been calculated using a 3D finite element model. To limit rotor loss we then used a non-conductive retaining sleeve (heat shrink sleeve). In the winding, we used bar-wound conductors, which is an original winding technology developed in our laboratory, and whose advantage among others is the unusual copper fill factor that reaches almost 90%.Subsequently, we explored the high frequency machines (>1 kHz) in order to increase the power-to-weight ratio (cross the threshold of 2.5 kW/kg). We proposed, the following to the analytical and finite element study, a first conventional prototype with a power-to-weight ratio equal to 4.5 kW/kg with: FeCo stator (Vacodur49 0.2 mm), FeSi rotor and NdFeB magnets (N35EH), operated at 1666 Hz, 5000 RPM and 94% efficiency at full load. A second motor had been also proposed with both rotor and winding in aluminum, in this case the power-to-weight ratio reaches around 6 kW with, however, less efficiency (93%).Finally, this HF motor was tested, at no load, on the aforementioned test bench. The experiments were carried out on a multitude of FeCo and FeSi stator core samples coming from different manufacturing processes (insulation: bonding varnish and C-5 varnish; cutting: laser and EDM “Electrical Discharge Machining”; thermal treatment) in real operating conditions of a high frequency PM machine in order to experimentally obtain the famous “additional coefficient” of iron losses (Kadd).
312

Interface entre a proteção à propriedade intelectual e o direito de concorrência no Brasil / The Interface Between Intellectual Property and Competition Law in Brazil

Brito Junior, Jorge Luiz de 02 March 2015 (has links)
Embora os direitos de Propriedade Intelectual (PI) sejam supostamente instituídos de forma a fomentar a inovação e o bem-estar em longo prazo, seu uso pode ensejar comportamentos oportunistas e abusivos como os Artigos 8.2 e 40 do TRIPS expressamente admitem. Sempre que tal tipo de comportamento afetar a concorrência em determinado mercado excluindo concorrentes, impondo barreiras à entrada, prejudicando consumidores por meio de aumento de preços ou redução da oferta o Direito de Concorrência será chamado a intervir. Considerando tais questões, o objetivo desse trabalho é identificar um quadro de trabalho brasileiro para tratar de questões envolvendo questões de Direito de Concorrência relacionadas à Propriedade Intelectual. O autor buscou delinear os conceitos de uso abusivo de direitos de Propriedade Intelectual, Dominação de Mercado por meio de uso da Propriedade Intelectual e de abuso de posição dominante, considerando o novo quadro regulatório introduzido pela Lei 12.259/2001. / While intellectual property (IP) rights are usually claimed to be designed to foster innovation and welfare in the long run, their use may give rise to opportunistic, abusive behavior - as Articles 8.2 and 40 of TRIPS openly admit. Whenever such sort of behavior affects competition in a given market - whether by dislodging competitors, imposing barriers to entry, harming costumers, raising prices or reducing output - competition law is called to intervene. Considering these issues, the purpose of this paper is to identify a Brazilian legal framework for dealing with IP related competition issues. The author sought to draw the legal concepts of abusive of IP rights, market domination and abuse of dominant position considering the new regulatory framework introduced by Law 12.259/2011.
313

Doença hepática gordurosa não alcoólica (DHGNA) em pacientes morbidamente obesos submetidos à cirurgia bariátrica : correlação entre os achados histopatológicos das biópsias hepáticas intraoperatórias e estado glicêmico basal

Souto, Kátia Elisabete Pires January 2017 (has links)
Introdução: A Doença Hepática Gordurosa Não Alcoólica (DHGNA) tem como causa principal a obesidade. Atualmente não existe tratamento medicamentoso específico para DHGNA. A cirurgia bariátrica surge como uma alternativa de tratamento em pacientes morbidamente obesos. Objetivos: Analisar, através de biópsia hepática intra-operatória, o grau de comprometimento hepático em obesos submetidos à cirurgia bariátrica, correlacionando os achados histopatológicos com o estado glicêmico dos pacientes. Métodos: Estudo de coorte prospectivo incluindo 521 pacientes submetidos à cirurgia bariátrica de julho de 2001 até dezembro de 2016. Os pacientes foram classificados em três grupos de acordo com o status glicêmico basal: 167(32,05%) diabéticos tipo 2 (G1), 132 (25,33%) pré-diabéticos (G2) e 222 (42,61%) obesos normoglicêmicos (G3). Foram obtidas biópsias hepáticas transoperatórias, as quais foram classificadas conforme os critérios de Brunt e do NASH-CRN. As variáveis clínicas e bioquímicas e histológicas foram comparadas antes da cirurgia e durante o seguimento pós-operatório. Resultados: A prevalência de DHGNA nesta coorte foi de 95%. Não houve diferença quanto ao gênero e IMC entre os grupos. Observaram-se taxas mais altas de fibrose (56,4% G1 vs 29,2% G2 vs 28,6% G3 p<0,001) e Esteatohepatite Não Alcoólica (EHNA) (59,4% G1vs 49,2% G2 vs 36% G3 p <0,001) nos pacientes diabéticos. Apenas 1,5 %, dos diabéticos apresentaram histologia normal (vs 7,76% G2 vs 15,7% G3). / Introduction: Obesity is the main cause of nonalcoholic fatty liver disease (NAFLD), for which there is currently no specific medical treatment. Bariatric surgery is a treatment alternative for morbidly obese patients. Objectives: Use an intraoperative liver biopsy to analyze the degree of liver damage in obese patients submitted to bariatric surgery and correlates the histopathological findings with glucose status. Methods: Prospective cohort study of 521 morbid obese patients undergoing bariatric surgery from July 2001 to December 2016, classified into three groups according to their baseline glucose status: 167 (32.05%) type 2 diabetes (G1), 132 (25.33%) pre-diabetic (G2) and 222 (42.61%) normoglycemic obese (G3). Patients using potentially hepatotoxic medications and a history of ethanol consumption or viral hepatitis were excluded. Intraoperative liver biopsies were obtained and classified in accordance with Brunt and NASH-CRN criteria. Clinical, biochemical and histopathological variables were compared before surgery and during postoperative follow-up. Results: The prevalence NAFLD was 95%. There was no intergroup difference for sex and BMI. Higher rates of fibrosis (56.4% G1 vs. 29.2% G2 vs. 28.6% G3 p<0.001) and nonalcoholic steatohepatitis (NASH) (59.4% G1vs 49.2% G2 vs. 36% G3 p <0.001) were observed in the diabetic patients. Only 1.5 % of diabetics showed normal histology (vs. 7.76% G2 and 15.7% G3).
314

On magnetic amplifiers in aircraft applications

Austrin, Lars January 2007 (has links)
<p>In the process of designing an electric power supply system for an aircraft, parameters like low weight and low losses are important. Reliability, robustness and low cost are other important factors. In the Saab Gripen aircraft, the design of the primary power supply of the electric flight control system was updated by exchanging a switching transistor regulator to a magnetic amplifier (magamp). By introducing a magamp design, weight was saved and a more reliable power supply system at a lower cost was achieved.</p><p> In this particular case, with the power supply of the electric flight control system in the Saab Gripen fighter, advantage could be taken of a specific permanent magnet generator (PM-generator). The frequency of the generator offered the perfect conditions for a magamp controller. A key parameter in designing magnetic amplifiers (magamps) is low losses. New amorphous alloys offer new possibilities of the technique in designing magnetic amplifiers, because of their extremely low losses.</p><p> The core losses are evaluated by studying the equations and diagrams specifying the power losses. The core losses are evaluated and compared with the copper losses in the process of optimizing low weight and low losses. For this an engineering tool is developed and demonstrated.</p><p> Evaluations of the hysteresis characteristics for the magnetic alloys, as well as modeling and simulation of the core losses, are presented in this work. The modeling of the core losses includes hysteresis losses, eddy current losses and excess losses as well as copper losses. The losses are studied dynamically during realistic operational conditions. The model can be used for any generic analysis of hysteresis in magnetic circuits. Applications of magnetic amplifiers in aircrafts have been demonstrated to be a feasible alternative</p>
315

Doença hepática gordurosa não alcoólica (DHGNA) em pacientes morbidamente obesos submetidos à cirurgia bariátrica : correlação entre os achados histopatológicos das biópsias hepáticas intraoperatórias e estado glicêmico basal

Souto, Kátia Elisabete Pires January 2017 (has links)
Introdução: A Doença Hepática Gordurosa Não Alcoólica (DHGNA) tem como causa principal a obesidade. Atualmente não existe tratamento medicamentoso específico para DHGNA. A cirurgia bariátrica surge como uma alternativa de tratamento em pacientes morbidamente obesos. Objetivos: Analisar, através de biópsia hepática intra-operatória, o grau de comprometimento hepático em obesos submetidos à cirurgia bariátrica, correlacionando os achados histopatológicos com o estado glicêmico dos pacientes. Métodos: Estudo de coorte prospectivo incluindo 521 pacientes submetidos à cirurgia bariátrica de julho de 2001 até dezembro de 2016. Os pacientes foram classificados em três grupos de acordo com o status glicêmico basal: 167(32,05%) diabéticos tipo 2 (G1), 132 (25,33%) pré-diabéticos (G2) e 222 (42,61%) obesos normoglicêmicos (G3). Foram obtidas biópsias hepáticas transoperatórias, as quais foram classificadas conforme os critérios de Brunt e do NASH-CRN. As variáveis clínicas e bioquímicas e histológicas foram comparadas antes da cirurgia e durante o seguimento pós-operatório. Resultados: A prevalência de DHGNA nesta coorte foi de 95%. Não houve diferença quanto ao gênero e IMC entre os grupos. Observaram-se taxas mais altas de fibrose (56,4% G1 vs 29,2% G2 vs 28,6% G3 p<0,001) e Esteatohepatite Não Alcoólica (EHNA) (59,4% G1vs 49,2% G2 vs 36% G3 p <0,001) nos pacientes diabéticos. Apenas 1,5 %, dos diabéticos apresentaram histologia normal (vs 7,76% G2 vs 15,7% G3). / Introduction: Obesity is the main cause of nonalcoholic fatty liver disease (NAFLD), for which there is currently no specific medical treatment. Bariatric surgery is a treatment alternative for morbidly obese patients. Objectives: Use an intraoperative liver biopsy to analyze the degree of liver damage in obese patients submitted to bariatric surgery and correlates the histopathological findings with glucose status. Methods: Prospective cohort study of 521 morbid obese patients undergoing bariatric surgery from July 2001 to December 2016, classified into three groups according to their baseline glucose status: 167 (32.05%) type 2 diabetes (G1), 132 (25.33%) pre-diabetic (G2) and 222 (42.61%) normoglycemic obese (G3). Patients using potentially hepatotoxic medications and a history of ethanol consumption or viral hepatitis were excluded. Intraoperative liver biopsies were obtained and classified in accordance with Brunt and NASH-CRN criteria. Clinical, biochemical and histopathological variables were compared before surgery and during postoperative follow-up. Results: The prevalence NAFLD was 95%. There was no intergroup difference for sex and BMI. Higher rates of fibrosis (56.4% G1 vs. 29.2% G2 vs. 28.6% G3 p<0.001) and nonalcoholic steatohepatitis (NASH) (59.4% G1vs 49.2% G2 vs. 36% G3 p <0.001) were observed in the diabetic patients. Only 1.5 % of diabetics showed normal histology (vs. 7.76% G2 and 15.7% G3).
316

Avalia??o do Programa Mais M?dicos nos Vales do Jequitinhonha e Mucuri

Pereira, Elizeu de Castro 12 September 2017 (has links)
Incluir como ag?ncias financiadoras: Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG), Funda??o Diamantinense de Apoio ao Ensino, Pesquisa e Extens?o (FUNDAEPE). / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-01-09T21:32:26Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) elizeu_castro_pereira.pdf: 2314835 bytes, checksum: 338417e044a8319ff002f1ba8f047555 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-01-19T17:09:50Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) elizeu_castro_pereira.pdf: 2314835 bytes, checksum: 338417e044a8319ff002f1ba8f047555 (MD5) / Made available in DSpace on 2018-01-19T17:09:50Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) elizeu_castro_pereira.pdf: 2314835 bytes, checksum: 338417e044a8319ff002f1ba8f047555 (MD5) Previous issue date: 2017 / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Funda??o Diamantinense de Apoio ao Ensino, Pesquisa e Extens?o (FUNDAEPE) / O Programa Mais M?dicos para o Brasil foi implementado pelo Governo Federal nos Vales do Jequitinhonha e Mucuri de 2013 a 2016. V?rios fatores influenciam na satisfa??o dos profissionais m?dicos na presta??o de servi?o. A avalia??o desses fatores ? importante, pois pode trazer alternativas para a amplia??o da perman?ncia desses profissionais nas Unidades B?sicas de Sa?de, apontar lacunas importantes nas Estrat?gias Sa?de da Fam?lia e no Programa Mais M?dicos e, assim, subsidiar a??es efetivas no ?mbito da Aten??o Prim?ria em Sa?de, direcionadas ?s equipes de sa?de da fam?lia e equacionar as dificuldades apresentadas nas Unidades B?sicas de Sa?de do munic?pio de Diamantina, bem como dos demais munic?pios dos Vales do Jequitinhonha e Mucuri. O objetivo do presente projeto foi avaliar a satisfa??o dos m?dicos do Programa Mais M?dicos para o Brasil nos Vales do Jequitinhonha e Mucuri. Tratou-se de um estudo descritivo, o qual foi realizado por meio de uma estrat?gia de combina??o de abordagens quantitativas, denominada triangula??o de m?todos. A popula??o de estudo foi constitu?da por 90 m?dicos, distribu?dos nos 82 munic?pios dos Vales em quest?o. Dos 82 munic?pios investigados foi constatado que apenas 23, at? o momento, n?o fizeram ades?o ao Programa Mais M?dicos para o Brasil. Em rela??o ? satisfa??o dos profissionais m?dicos foi verificado, atrav?s da escala de Likert, que 63% (n=90) dos que responderam as perguntas relacionadas ? satisfa??o se encontram totalmente satisfeitos. Esses dados foram corroborados com outras an?lises estat?sticas como o dendograma e an?lise multicrit?rios. Foi observada a correla??o entre a satisfa??o dos m?dicos e o maior grau de escolaridade. Os resultados alcan?ados nessa pesquisa permitem visualizar quest?es importantes do Programa Mais M?dicos para o Brasil e, desta forma, subsidiar a??es efetivas no ?mbito da Aten??o Prim?ria ? Sa?de. / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Sa?de, Sociedade e Ambiente, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / More Doctors Program for Brazil was implemented by the Federal Government in the Jequitinhonha and Mucuri Valleys from 2013 to 2016. Several factors influence the satisfaction of medical professionals in the provision of services. The evaluation of these factors is important, since it can provide alternatives for the expansion of the permanence of these professionals in the Basic Health Units. It is believed that the results achieved so far may point to important shortcomings in the Family Health Strategies and the Medical Program and thus, subsidize effective actions in the scope of Primary Health Care directed to the family health teams and equate the difficulties presented in the Basic Health Units of the municipality of Diamantina and also of other municipalities of the Jequitinhonha and Mucuri Valleys. The objective of the present project was to evaluate More Doctors Program for the Brazilians in the Jequitinhonha and Mucuri Valleys. This was a descriptive study, which was carried out through a combination strategy of quantitative approaches, called method triangulation. The study population consisted of 90 physicians, divided among the 82 municipalities of the concerned Valleys. Of the 82 municipalities investigated, it was verified that only 23, untill now, they did not join More Doctor Program for Brazilians. Related to the satisfaction of medical professionals, 63% (n = 90) of those who answered the questions related to satisfaction they were found fully satisfied with the Likert scale. These data were corroborated with other statistical analyzes such as dendrogram and multicriteria analysis. Correlation between physician satisfaction and educational level was observed. The results obtained in this research allow to visualize important issues of More Doctor Program for Brazilians and thus subsidize effective actions in the ambit of the Primary Healthy Care. / El Programa M?s M?dicos para Brasil (PMMB) fue implementado por el Gobierno Federal en los Valles del Jequitinhonha y Mucuri de 2013 a 2016. Varios factores influencian en la satisfacci?n de los profesionales m?dicos en la prestaci?n de servicio. La evaluaci?n de estos factores es importante, pues puede traer alternativas para la ampliaci?n de la permanencia de esos profesionales en las Unidades B?sicas de Salud, se?alar lagunas importantes en las Estrategias Salud de la Familia y en el Programa M?s M?dicos y, as?, subsidiar acciones efectivas en el ?mbito de la Atenci?n Primaria en De la Salud, dirigidas a los equipos de salud de la familia y abordar las dificultades presentadas en las Unidades B?sicas de Salud del municipio de Diamantina, as? como de los dem?s municipios de los Valles del Jequitinhonha y Mucuri. El objetivo del presente proyecto fue evaluar la satisfacci?n de los m?dicos del Programa M?s M?dicos para Brasil en los Valles del Jequitinhonha y Mucuri. Se trat? de un estudio descriptivo, el cual fue realizado por medio de una estrategia de combinaci?n de abordajes cuantitativos, denominada triangulaci?n de m?todos. La poblaci?n de estudio fue constituida por 90 m?dicos, distribuidos en los 82 municipios de los Valles en cuesti?n. De los 82 municipios investigados se constat? que s?lo 23, hasta el momento, no hicieron adhesi?n al PMMB. En cuanto a la satisfacci?n de los profesionales m?dicos se verific?, a trav?s de la escala de Likert, que el 63% (n = 90) de los que respondieron las preguntas relacionadas a la satisfacci?n se encuentran totalmente satisfechos. Estos datos fueron corroborados con otros an?lisis estad?sticos como el dendograma y an?lisis multicriterios. Se observ? la correlaci?n entre la satisfacci?n de los m?dicos y el mayor grado de escolaridad. Los resultados alcanzados en esta investigaci?n permiten visualizar cuestiones importantes del PMMB y, de esta forma, subsidiar acciones efectivas en el ?mbito de la APS.
317

Conception préliminaire d'actionneurs électromécaniques - outils d'aide à la spécification et à la génération de procédures de dimensionnement pour l'optimisation / Preliminary design of electromechanical actuators – development of tools dedicated to technical specification and optimal sizing sequence conditioning

Reysset, Aurelien 23 January 2015 (has links)
Cette thèse a pour objectif d’apporter un ensemble d’outils logiciels s’inscrivant dans une méthodologie globale de conception de systèmes mécatroniques. Elle arrive en complément de travaux déjà menés au sein du laboratoire sur le pré-dimensionnement d’actionneurs aéronautiques de nouvelle génération : les actionneurs électromécaniques (EMA). Cette technologie apporte de nouvelles problématiques qui forcent les ingénieurs à modifier leur processus de développement et ce dès la phase de spécification où des profils de mission devront être générés/transformés/analysés de manière à simplifier la conception et assurer leur validation. Une toolbox Simulink a donc été créée dans cette thèse pour répondre à ce besoin de transformation de l’information entre avionneur et systémier. Comme tout système embarqué, le concepteur fait face à des compromis entre performances, durée de vie et intégration, qui peuvent se résumer à un problème d’optimisation décrit par un ensemble d’équations et de contraintes. Un effort particulier de description a été mené sur le conditionnement de ces équations sous la forme d’un séquencement de calculs explicites adaptés aux algorithmes d’optimisation. La méthode et son implémentation logicielle, toutes deux basées sur la théorie des graphes, interagissent avec le concepteur de manière à l’informer des erreurs de singularité ou de bouclages algébriques apparaissant dans son problème et à lui fournir des pistes de résolution. Pour finir, des études de pré-dimensionnement d’actionneurs de train d’atterrissage et de surfaces de vol primaires (aileron et spoiler), réalisées dans le cadre de cette thèse, dresseront les possibilités offertes par cette approche innovante : conception intégrée avec une cinématique complexe, conception collaborative pluri-partenaires découplée, utilisation de surfaces de réponse pour accélérer l’optimisation / The aim of this thesis is to bring a package of software tools included in a whole methodology dealing with mechatronic systems design. It comes as an add-on to the work already carried out at the laboratory in the field of the new generation of aircraft actuation systems: electromechanical actuators (EMA). This technology triggers new problematics leading the engineers to modify their development process as early as the specification phase, when mission profiles have to be generated/transformed/analyzed in order to simplify the design and ensure the validation step. Thus a Simulink toolbox has been created to meet the need for an information translator working as an intermediate between airframer and system-supplier. As for all the embedded systems, the designer has to face some performance-lifetime-integration trade-off, which can be considered as an optimization problem described by a set of equations and constraints. Particular attention is paid here to the conditioning of those explicit equations in order to obtain a standardized calculation sequence adapted to many optimization algorithms. The method and implemented software, both based on the graph theory, interact with the designer to inform him on the possible singularity and algebraic loop issues, providing some leads for their resolution. Finally, some preliminary sizing studies of landing gear and primary flight control surfaces (aileron and spoiler) actuation systems are presented to highlight the possibilities brought out by this innovative approach: integrated design with complex kinematics, collaborative multi-partners design, use of response surfaces to speed up the optimization
318

Conception et réalisation d'un convertisseur multicellulaire DC/DC isolé pour application aéronautique / Design and development of an isolated multicell DC/DC power converter for aeronautical applications

Brandelero, Julio Cezar 28 May 2015 (has links)
L’électricité prend une place de plus en plus importante dans les systèmes énergétiques embarqués. L’électricité est une forme d’énergie très malléable, facile à transporter et réglable ou transformable avec un très faible taux de pertes. L’énergie électrique, associée à des convertisseurs statiques, est plus facile à maîtriser que, par exemple, l’énergie hydraulique et/ou pneumatique, permettant un réglage plus fin et une réduction des coûts de maintenance. L’évolution de la puissance dans les modèles avioniques est marquante. Avec le nombre croissant de charges électroniques, un avion plus électrique avec un réseau à courant alternatif inclurait un grand nombre de redresseurs AC/DC qui devront respecter les normes de qualité secteur. Une solution pour la réduction de la masse serait de préférer un réseau HVDC (High Voltage DC Bus). Sur les futurs modèles avioniques plus électriques, les concepteurs envisageront des conversions HVDC/DC à partir de l’unité appelée BBCU (Buck Boost Converter Unit). Dans ce cas d’étude, un réseau de distribution en tension continue (±270Vdc) est connecté à un réseau de sécurité basse tension (28Vdc) avec un échange bidirectionnel de puissance pouvant atteindre 10kW. Le convertisseur statique assurant cette liaison représente de nouveaux défis pour l’électronique de puissance en termes de fiabilité, sûreté, détection de panne, rendement et réduction de masse et de coût. Le dimensionnement du convertisseur doit prendre en compte une conception optimale, en aéronautique ce critère est la masse. Dans le processus de dimensionnement et d’optimisation du convertisseur, il est donc impératif de prendre en compte trois facteurs principaux : 1) l’évolution des topologies de conversion, 2) l’évolution des composants actifs et passifs et 3) l’intégration de puissance. La réunion de ces trois facteurs permettra ainsi la miniaturisation des convertisseurs statiques. Dans un premier temps, nous préciserons la démarche adoptée pour le dimensionnement d’un convertisseur en prenant en compte : les topologies actives, les filtres différentiels et le système de refroidissement. Les différents éléments qui composent le convertisseur sont décrits dans un langage informatique orienté objet. Des facteurs de performances seront également introduits afin de faciliter le choix des semi-conducteurs, des condensateurs et du dissipateur pour un convertisseur statique. Dans un deuxième temps, nous présenterons le fonctionnement d’une topologie multicellulaire DC/DC, isolée pour l’application proposée. Nous présenterons les avantages du couplage de différentes phases de ce convertisseur. Nous introduirons les différentes associations des cellules et leurs avantages, possibles grâce à l’isolement, comme la mise en série et en parallèle. Puisque la caractérisation des pertes des semi-conducteurs est essentielle pour le dimensionnement du convertisseur statique, nous proposerons deux approches : un modèle de simulation relativement simple et paramétré à l’aide de seules notices constructeurs ; et une méthode de mesure des pertes dans les semi-conducteurs qui est à la fois précise et compatible avec les composants les plus rapides. En ce qui concerne les composants magnétiques, une surface de réponse des matériaux ferrites sera présentée. Nous allons décrire, par le biais analytique et de simulation, des modèles pour la détermination du champ magnétique à l’intérieur du noyau et des ondulations de courant engendrés. Finalement, en profitant des modèles et des résultats obtenus dans les sections précédentes, nous montrerons le dimensionnement et la réalisation de chaque partie du convertisseur BBCU 100kHz / 10kW. Une perspective d’un design idéal est également présentée. / The electricity is taking a more important place in the embedded systems. The electricity is a very moldable form of energy, easy to transport and adjustable or transformed with a very low losses. The electrical energy, associated with power converters, is easier to control than hydraulic and/or pneumatic energies for example, allowing a finer regulation and a cost cutting of maintenance. The installed power in the avionic models is growing fast. With the increasing number of electronic loads, a more electrical aircraft with an AC network would include a large number of rectifiers AC/DC which will have to respect the quality standards. A solution for the reduction of the mass would be to prefer a HVDC network (High Voltage DC BUS). On the future more electrical aircrafts, the designers will be facing a HVDC/DC power conversion. This is the role of the unit called BBCU (Buck Boost Converter Unit). In our case of study, a distribution network in DC voltage (± 270Vdc) is connected to a security low-voltage network (28Vdc) which includes a bidirectional power exchanges achieving 10kW. The power converter for this connection gives new challenges for the power electronics in terms of reliability, safety, failure detection, efficiency and reduction of mass and cost. The design of the power converter needs to take into account for an optimal design. It is thus imperative to take into account three main factors: 1) the evolution of the power topologies 2) the evolution of the active and passive devices and 3) the power integration. The meeting of these three factors will allow the miniaturization of the power converters. At first, the adopted approach for designing power converters, taking into account the power topology, the differential filters and the cooling system are presented. The various elements which compose the power converter are described in an Object-Oriented Programming. The performance factors will be introduced to facilitate the choice of semiconductors, capacitors and heat-sinks. Secondly, the operation phases of a multicellular isolated DC/DC topology for the proposed application are presented. A discussion of the advantages of the magnetic coupling is also introduced. Thanks to the isolation, different associations of switching cells, series or/and parallel connection, are possible. Knowing the losses of power semiconductors is an essential step to design a power converter, thus two approaches are proposed: 1) a simulation model using a relatively simple model with the datasheets information; and 2) a losses measurement method which is precise and compatible with the fastest devices. As regards the magnetic components, a response surface of ferrite materials will be presented. Some models for the determination of the magnetic field inside the core and the current ripple are also described. Finally, by taking advantage of models and results obtained in the previous sections, the design and the realization of each party of the BBCU power converter 100kHz / 10kW is showed. A perspective of an ideal design is also presented.
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Teologické myšlení anglického krále Jindřicha VIII. / The theological mind of the english king Henry VIII

KRAMEROVÁ, Lenka January 2014 (has links)
The first chapter of this degree work presents some personalities of Henry´s age. These personalities influenced him. Apprises there with Machiavelli´s The Prince, More´s Utopia a some Luther´s works. At the second chapter we learn something of lifes of Henry and Luther and of their important works, Luther´s On the babylonish captivity of the church and Henry´s Defence of the Seven Sacraments. This work finishes with summary of reformation in England.
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Doença hepática gordurosa não alcoólica (DHGNA) em pacientes morbidamente obesos submetidos à cirurgia bariátrica : correlação entre os achados histopatológicos das biópsias hepáticas intraoperatórias e estado glicêmico basal

Souto, Kátia Elisabete Pires January 2017 (has links)
Introdução: A Doença Hepática Gordurosa Não Alcoólica (DHGNA) tem como causa principal a obesidade. Atualmente não existe tratamento medicamentoso específico para DHGNA. A cirurgia bariátrica surge como uma alternativa de tratamento em pacientes morbidamente obesos. Objetivos: Analisar, através de biópsia hepática intra-operatória, o grau de comprometimento hepático em obesos submetidos à cirurgia bariátrica, correlacionando os achados histopatológicos com o estado glicêmico dos pacientes. Métodos: Estudo de coorte prospectivo incluindo 521 pacientes submetidos à cirurgia bariátrica de julho de 2001 até dezembro de 2016. Os pacientes foram classificados em três grupos de acordo com o status glicêmico basal: 167(32,05%) diabéticos tipo 2 (G1), 132 (25,33%) pré-diabéticos (G2) e 222 (42,61%) obesos normoglicêmicos (G3). Foram obtidas biópsias hepáticas transoperatórias, as quais foram classificadas conforme os critérios de Brunt e do NASH-CRN. As variáveis clínicas e bioquímicas e histológicas foram comparadas antes da cirurgia e durante o seguimento pós-operatório. Resultados: A prevalência de DHGNA nesta coorte foi de 95%. Não houve diferença quanto ao gênero e IMC entre os grupos. Observaram-se taxas mais altas de fibrose (56,4% G1 vs 29,2% G2 vs 28,6% G3 p<0,001) e Esteatohepatite Não Alcoólica (EHNA) (59,4% G1vs 49,2% G2 vs 36% G3 p <0,001) nos pacientes diabéticos. Apenas 1,5 %, dos diabéticos apresentaram histologia normal (vs 7,76% G2 vs 15,7% G3). / Introduction: Obesity is the main cause of nonalcoholic fatty liver disease (NAFLD), for which there is currently no specific medical treatment. Bariatric surgery is a treatment alternative for morbidly obese patients. Objectives: Use an intraoperative liver biopsy to analyze the degree of liver damage in obese patients submitted to bariatric surgery and correlates the histopathological findings with glucose status. Methods: Prospective cohort study of 521 morbid obese patients undergoing bariatric surgery from July 2001 to December 2016, classified into three groups according to their baseline glucose status: 167 (32.05%) type 2 diabetes (G1), 132 (25.33%) pre-diabetic (G2) and 222 (42.61%) normoglycemic obese (G3). Patients using potentially hepatotoxic medications and a history of ethanol consumption or viral hepatitis were excluded. Intraoperative liver biopsies were obtained and classified in accordance with Brunt and NASH-CRN criteria. Clinical, biochemical and histopathological variables were compared before surgery and during postoperative follow-up. Results: The prevalence NAFLD was 95%. There was no intergroup difference for sex and BMI. Higher rates of fibrosis (56.4% G1 vs. 29.2% G2 vs. 28.6% G3 p<0.001) and nonalcoholic steatohepatitis (NASH) (59.4% G1vs 49.2% G2 vs. 36% G3 p <0.001) were observed in the diabetic patients. Only 1.5 % of diabetics showed normal histology (vs. 7.76% G2 and 15.7% G3).

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