Preplaced aggregate concrete (PAC) is produced by grouting high workability cement based grouts among the voids of compacted coarse aggregate mass. Because of its low shrinkage, PAC has been used for many repair jobs like; tunnel lines, dams and bridge piers. Moreover, it has been used for underwater construction. Grout has a major effect on the properties of produced PAC and well defined grout controls the properties of resulted PAC. The effect of types and amount of powder materials, admixtures, sand and water content on the properties of fresh and hardened grout for the production of PAC have been investigated. Tests on hardened grout and PAC properties have also been carried out to investigate the most important effects. A correlation between hardened properties of grout and PAC has also been analyzed. Grout rheology using four different gradation sands at two different cement-sand and at different w/c ratios ratios has been identified experimentally; no added chemical admixtures or mineral additives had first employed, then superplasticizer (SP) was added at 2% and 1%, and finally a combination of 1% SP and pulverized fuel ash (Pfa) at 20% of the cement weight was employed for all mixes. Grout tests have included two point workability tests by the Viskomat NT, flow time funnel test, Colcrete flow meter test, and water bleeding test. After that, eighteen grout mixes with high workability were produced using three different sands at three w/c ratios and two c/s ratios with 1% SP and Pfa at 20% of the cement weight were designed. Eighteen hardened grout and PAC then produced and their compressive strength and sorptivity were tested. Grout rheology can be defined by the rheology of cement paste employed and the internal distance between sand particles. The effect of sand surface texture on grout rheology is important at very low internal distances. Fresh grout yield stress is the most important property which gives the same degree of sensitivity for all grouts regardless the material type and content used in the mix. There are strong relations between compressive strength of grout and PAC, but less correlation between them in sorptivity test because of the effect high quantity of coarse aggregate of PAC. Sorptivity of PAC is low comparing with different kinds of concrete suggesting its advantage for underwater construction.

Les nanorubans de carbone présentent aujourd’hui un grand intérêt en tant que segments de graphène aux propriétés électroniques modulables. Alors que des techniques de synthèse destructives top down donnent des rubans de très grande taille, d’autres techniques constructives bottom up, par synthèse organique, pourraient former des nanorubans bien définis de géométries contrôlées. Dans cette optique, la réaction de Scholl est un outil chimique précieux car elle permet la graphénisation de longs précurseurs flexibles de type polyphénylène.Etonnamment, des structures distordues peuvent être obtenues majoritairement même si des isomères plans moins encombrés sont a priori favorisés. Nous avons ainsi montré que contre toute attente même un encombrement stérique important n’a aucun effet notoire sur la régiosélectivité et que des composés aromatiques polycycliques courbés sont préférentiellement formés. Ainsi, des structures particulièrement tordues, tel que l’hexabenzotriphénylène (HBTP) peuvent être facilement obtenues à partir de précurseurs de type polyphénylène.Après avoir découvert cette régiosélectivité inattendue, nous en avons tiré parti pour former des composés de type polyhélicène. Plusieurs tentatives de formation de l’hexaphénanthrotriphénylène (HPTP) furent infructueuses à cause de problèmes de réactivité lors des synthèses des précurseurs flexibles correspondants. En mettant au point une stratégie de synthèse versatile fondée sur un précurseur commun, plusieurs substrats flexibles de symétrie C3 ont été synthétisés puis soumis à la réaction de Scholl. Des produits de réarrangement ont cependant été obtenus au détriment des [6]hélicènes attendus. Toutefois, un HBTP fonctionnalisé par des groupements TMS a pu être efficacement préparé, ainsi qu’un hexabenzocoronène (HBC) dont l’exceptionnelle solubilité est due à la distorsion du coeur aromatique sous l’effet des groupements encombrants situés dans les régions baie.Ce fragment [5]hélicène favorisé a enfin été incorporé dans la formulation de nanorubans de carbone tordus, alors composés d’une succession de ce motif. En tant que réactions test, les synthèses du monomère et du dimère correspondants ont été effectuées avec d’excellents rendements et les deux composés entièrement caractérisés. Leurs structures ont été déterminée par diffraction de rayons X sur monocristaux et ont fourni d’intéressantes informations complémentaires quant à leurs configurations. Une stratégie plus générale a enfin été développée et optimisée pour la synthèse systématique d’oligomères plus longs de nanorubans de carbone tordus. En utilisant cette technique les trimère et tétramère correspondants ont été synthétisés et caractérisés par spectrométrie de masse. / Carbon nanoribbons are today of great interest as graphene segments with modulable electronic properties. Whilst top down techniques give giant ribbons, bottom-up organic synthesis may lead to exactly designed nanoribbons of controlled geometries. The Scholl reaction is a precious chemical tool for that purpose since it yields efficiently to the graphitization of long and flexible polyphenylene precursors.Surprisingly, twisted structures may be obtained preferentially even if less crowded isomers are also feasible. It has been shown that, against all expectation, even a strong steric hindrance has no marked effect on regioselectivity and highly twisted polycyclic aromatic hydrocarbons are sometimes preferentially formed, whereas their flat and more symmetrical isomers are only obtained in minority. Highly twisted structures such as hexabenzotriphenylene (HBTP) may then be obtained very easily from flexible polyphenylene precursors.After discovering this unexpected regioselectivity, we used it on purpose to form polyhelicenic species. Attempts to prepared hexaphenanthrotriphenylene (HPTP) were unsuccessful due to reactivity issues when synthesizing the corresponding flexible precursors. By using a new versatile strategy leading to an advanced common precursor, several C3-symmetrical flexible substrates have been synthesized and submitted to Scholl reaction. The expected [6]helicenes were not obtained and rearranged products were formed instead, but TMS-bearing HBTP could be prepared, as well as a hexabenzocoronene (HBC) which exceptionnal solubility is due to the distortion of the aromatic core under the effect of bulky tert-butyl substituents in bay regions.The easily formed [5]helicene fragment has been incorporated in the design of twisted carbon nanoribbons that would be composed of a succession of such motifs. As a test reaction, the corresponding monomer and dimer have been synthesized with an excellent yield and fully characterized. Their X-ray structures have even been determined, giving interesting information about their configuration. A more general strategy has then been developed and optimized for the systematic synthesis of longer oligomers of twisted nanoribbons. Using this technique, the trimer and tetramer have been synthesized and characterized by mass spectrometry.

La prédiction du bruit émis par les unités extérieures des pompes à chaleur, provenant en partie des batteries à ailettes, constitue un enjeu industriel important. L’obstacle majeur réside dans l’impossibilité de réaliser le calcul acoustique d’une batterie à ailettes avec les outils de simulation classiques (Éléments Finis de Frontière) à cause du trop grand nombre d’éléments nécessaires (près de 600 ailettes par mètre). Cette thèse a pour objectif d’exploiter la périodicité des batteries à ailettes afin de pouvoir calculer leur bruit rayonné à partir du rayonnement d’une seule ailette. La propagation des vibrations est décrite sous la forme d’une décomposition en ondes, autorisant la réalisation séparée des calculs pour chaque onde. Le déplacement en tout point de la structure est calculé à partir du déplacement d’un seul élément unitaire, obtenu par la Méthode des Éléments Finis (FEM). Un élément unitaire acoustique est spécialement défini, comprenant des baffles rigides destinés à représenter l’influence des autres ailettes de la structure. Le rayonnement de cet élément est calculé pour chaque onde en utilisant la méthode des Éléments Finis de Frontière (BEM), puis dupliqué spatialement en tenant compte de la nature propagative des différentes ondes. Pour chaque structure étudiée, la comparaison avec le calcul direct de la structure complète montre une très bonne concordance avec des temps de calcul fortement réduits. L’influence de plusieurs paramètres sur le comportement de la structure a également été identifiée, mettant ainsi en évidence certains phénomènes particuliers propres aux structures périodiques. Dans la dernière partie de cette thèse, une validation expérimentale de l’approche périodique est proposée. Les résultats numériques sont comparables aux mesures vibratoires et acoustiques réalisées sur les batteries à ailettes. / The prediction of noise from outdoor units of heat pumps, partly coming from finned coils, is an important industrial issue. The major obstacle to the study of finned coils lies in the inability to perform the acoustic calculation with classic simulation tools (Boundary Element Method) because of the huge number of required elements (about 600 fins per meter). The goal of this thesis is to exploit the periodicity of finned coils in order to calculate the total noise radiated from the radiation of a single fin, and thus get rid of the number of fins composing the structure. The vibrations propagation is described as a wave decomposition, allowing the realization of separate calculations for each wave. The displacement at any point of the structure is calculated from the displacement of a single unit element, obtained with the Finite Element Method (FEM). An acoustic unit element is especially defined, comprising rigid baffles representing the influence of other fins of the structure. The radiation of this component is calculated for each wave using the Boundary Element Method (BEM), then spatially duplicated taking into account the propagation of the different waves. For each considered structure, a comparison with the direct calculation of the complete structure shows very good agreement with greatly reduced computation times. The influence of several parameters on the behaviour of the structure was also identified, thus highlighting some particular phenomena specific to periodic structures. In the last part of this thesis, an experimental validation of the periodic approach is proposed. Numerical results are close to vibratory and acoustic measurements done on the finned coils.

Made available in DSpace on 2016-04-26T20:48:41Z (GMT). No. of bitstreams: 1 Daniel Alves Hernandes.pdf: 1337208 bytes, checksum: 0a0dbe42d8949439ba3ce9356bf56c49 (MD5) Previous issue date: 2015-03-13 / Despite being considered as one of the main drivers for economic and social development, infrastructure services received low investments in the 1980s and 1990s in Brazil. As of 2002, with the introduction of government policies and direct governmental action in planning and funding, investments in key infrastructure sectors resumed. The Growth Acceleration Program (PAC) and investments in the transport sector where very important. The perspective created by public investment in infrastructure works as a trigger to attract private investment, in infrastructure itself, as in other economic sectors. Economic theory considers that the creation of such an environment is propitious for development / Apesar de ser apontado como um dos principais fatores propulsores do desenvolvimento econômico e social, os serviços de infraestrutura receberam pouco investimento nas décadas de 1980 e 1990 no Brasil. Foi a partir de 2002, com a introdução de políticas governamentais e ação direta do Estado no planejamento e financiamento, que os investimentos nos setores de infraestrutura foram retomados. Destaque para o Programa de Aceleração do Crescimento (PAC) e os investimentos realizados no setor de transportes. A perspectiva criada pelo investimento público em infraestrutura funcionou como um gatilho para atrair investimentos privados, tanto em infraestrutura, quanto em outros setores econômicos. Na teoria econômica, a criação de desse ambiente é propício para o desenvolvimento

Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2018-12-11T13:46:14Z No. of bitstreams: 1 Flavia Tarricone Jimenez.pdf: 36935564 bytes, checksum: 60c7cbf96dfdbbb3f36b5c91042074cb (MD5) / Made available in DSpace on 2018-12-11T13:46:14Z (GMT). No. of bitstreams: 1 Flavia Tarricone Jimenez.pdf: 36935564 bytes, checksum: 60c7cbf96dfdbbb3f36b5c91042074cb (MD5) Previous issue date: 2018-04-24 / This dissertation seeks to demonstrate a municipal experience that used federal resources, after the City Statute, in favela interventions proposing different measures and for this, verifying the specific needs of each precarious settlement. Jundia? was the city chosen for presenting diversity in the urbanization of favelas and in this work the interventions will be demonstrated through four nuclei: Jardins, S?o Camilo and Novo Horizonte, Parque Centen?rio and Vila Ana considering the period from 2010 to 2017. The research was developed from a theoretical review on the concept of urbanization of favelas in Brazil, the origins of the same, the municipal interventions in precarious settlements, considering the concepts post City Statute, demonstrating what is currently understood by urbanization of favelas in Brazil. The history of Jundia? was rescued with regard to housing of social interest and after, the previous and later projects were raised the interventions of the settlements studied as well as visits to the field to verify what was done. In this stage a detailed description of each intervention demonstrated through maps, plants and planialtimetric surveys was made. / A presente disserta??o busca, demonstrar uma experi?ncia municipal que utilizou recursos federais, ap?s o Estatuto da Cidade, nas interven??es de favelas propondo diferentes medidas e para isso, verificando as necessidades espec?ficas de cada assentamento prec?rio. Jundia? foi a cidade escolhida por apresentar diversidade na urbaniza??o de favelas e neste trabalho as interven??es ser?o demonstradas atrav?s de quatro n?cleos quais sejam: Jardins, S?o Camilo e Novo Horizonte, Parque Centen?rio e Vila Ana considerando o per?odo de 2010 ? 2017. A pesquisa desenvolveu-se a partir de uma revis?o te?rica sobre o conceito de urbaniza??o de favelas no Brasil, as origens das mesmas, as interven??es municipais em assentamentos prec?rios, considerando os conceitos p?s Estatuto da Cidade, demonstrando o que se entende atualmente por urbaniza??o de favelas no Brasil. Foi resgatada a hist?ria de Jundia? com rela??o ? habita??o de interesse social e ap?s, foram levantados os projetos anteriores e posteriores as interven??es dos assentamentos estudados bem como visitas ? campo para a verifica??o do que foi realizado. Nesta etapa foi feita uma descri??o detalhada de cada interven??o demonstradas atrav?s de mapas, plantas e levantamentos planialtim?tricos.

Um sistema de tratamento constituído de um reator anaeróbio de mistura completa e um reator anaeróbio compartimentado (ABR) foi operado durante 140 dias para estudar os efeitos do pré-tratamento das águas residuárias de uma indústria química, por carvão ativado em pó (CAP), e suas implicações nos processos de nitrificação e desnitrificação. Utilizou-se, no pré-tratamento do resíduo, duas concentrações de carvão ativado em pó. Para aplicação de 10 mg/l de CAP a remoção de DQO foi de 60% e a de NTK foi de 50%. Nesta fase, os processos de remoção de nitrogênio foram plenamente viabilizados. Para 5 mg/l de CAP a remoção de DQO foi de 44% e a remoção de NTK 46%, neste período se observou inibição por metais pesados e acúmulo de nitrito no sistema. / A treatment system composed of both an aerobic complete-mix reactor and a anaerobic baftled reactor (ABR) was operated for 140 days to study the effects of the treatment of wastewater chemical industry by powdered activate carbon (PAC) and its implications in nitrification - denitrification processes. In the residue preliminary treatment, two concentrations of PAC were used. For the application of 10 mg/l of CAP the removal of COD was 60% and the removal of TKN was 50%. In this phase, the processes of nitrogen removal were possible to be completely carried out. For 5 mg/l of CAP, the removal of COD was 44% and the removal of TKN 46%. In this period, the inhibition by heavy metaIs and nitrite accumulation in the system was observed.

Le sol est une ressource rare remplissant de nombreuses fonctions nécessaires au bon fonctionnement des écosystèmes et de nos sociétés. Malgré tout, il subit des pressions anthropiques à l’origine de sa déterioration. Ainsi en Europe, 16% du territoire est sujet à des degradations des sols. Une des menaces affectant l’homeostasie des sols est la contamination chimique issue des sites à activités industrielles. Ces sites contaminés, estimés au nombre 2,5 millions en Europe sont à l’origine d’un risque pour la santé humaine et environnementale. Malheureusement, à l’heure actuelle, il n’existe pas de cadre réglementaire européen commun concernant la gestion de ces sites, dont les diagnostics sont réalisés uniquement sur des listes restreintes de molécules et les polluants prioritaires. Cependant, la contamination des sols est généralement issue de mélanges complexes dont la toxicité est due à un ensemble de contaminants. L’objectif de cette thèse concerne l’identification de composés à l’origine de la toxicité des sols pollués en appliquant une analyse dirigée par l’effet (EDA), une technique qui combine des analyses biologiques et chimiques à un fractionnement physico-chimique. Après le développement de l’EDA pour les matrices solides, cette approche a été utilisée sur site afin d’identifier des composés liant le recepteur des hydrocarbures aromatiques (AhR). Ceci à permis de mettre au jour des contaminants à activité biologique non pris en compte dans les diagnostics des sols pollués tels que des hydrocarbures aromatiques polycycliques non prioritaires selon l’US-EPA, leurs produits d’oxydation ainsi que des composés contenant des N-,S-,O-Heterocyles. / The soil is a scarce resource fulfilling many functions necessary for the proper functioning of ecosystems and societies. Nevertheless, it suffers human pressures causing its deterioration. In Europe, 16% of the territory is subject to soil degradations. One of the threats to the soil homeostasis is the chemical contamination from industrial activity sites. These contaminated sites, estimated to number of 2.5 million in Europe are causing a risk to human and environmental health. Unfortunately, at present there is no common European regulatory framework for the management of these sites, whose diagnoses are made only on short lists of molecules and priority pollutants. However, soil contamination generally comes from complex mixtures whose toxicity is due to a combination of contaminants. The aim of this work concerns the identification of compounds responsible for the toxicity of the contaminated soil by applying an effect-directed analysis (EDA), a technique which combines biological and chemical analyzes to a physico-chemical fractionation. After the development of EDA on the solid matrices, this approach has been used on polluted sites to identify the compounds binding to the aryl hydrocabon receptor (AhR). This allowed to highlight contaminants with a biological activity not included in the diagnoses of polluted soils such as polycyclic aromatic hydrocarbons non-priority according to US-EPA, their oxidation products and compounds containing N -, S-, O-heterocycles.

Con el ánimo de contribuir a la construcción de la nueva cooperación comercial entre la Comunidad Europea (CE) y los países de África, el Caribe y el Pacífico (ACP), esta tesis se centra en el estudio del actual régimen de acceso a productos agrícolas concedido por la CE al grupo ACP. En concreto, se realiza un análisis y una evaluación del Protocolo del Azúcar CE-ACP (o, formalmente, el Protocolo nº 3 sobre el azúcar ACP), el cual aparece, por primera vez, en el Convenio de Lomé firmado el 28 de febrero de 1975. La principal preocupación por este instrumento de cooperación en particular es que su contenido es más beneficioso que el los demás Protocolos de productos agrícolas. Así, este acuerdo comercial sobre el azúcar es el único que se basa en un compromiso de compra, por parte de la CE, y de venta, por el lado de los ACP, de unas cantidades especificadas en el marco de un elevado precio garantizado. En la práctica, estos compromisos especiales han implicado transferencias monetarias sustanciales y un nivel de estabilidad significativo de los ingresos de exportación de azúcar para algunos de los países ACP participantes, especialmente para aquellos que presentaron vínculos comerciales históricos con Gran Bretaña. El objetivo final de este estudio consiste en proponer si el Protocolo del Azúcar CE-ACP debe ser integrado en los AAE o, por lo contrario, si es mejor mantenerlo bajo la posible exclusión permitida en el artículo XXIV del Acuerdo General sobre Aranceles y Comercio (GATT). Esta investigación también presenta la opción para el Protocolo del Azúcar de ser incluido en el Sistema de Preferencias Generalizadas (SPG) de la CE, aunque las reducciones arancelarias y no arancelarias, junto a las exenciones específicas, sean menos generosas que las otorgadas a las importaciones europeas de productos ACP. Con esta finalidad, en este estudio se efectúa una evaluación de impacto del Protocolo del Azúcar CE-ACP sobre el desarrollo económico de los países ACP beneficiarios. Con ello, se demuestra que las transferencias monetarias implícitas apropiadas por las empresas azucareras de los Estados ACP participantes no han logrado, en general, una expansión del bienestar económico de sus economías. Este resultado ha sido alcanzado utilizando distintos modelos econométricos: un modelo de regresión lineal, un modelo de corrección de errores y un modelo con datos panel. En consecuencia, concluimos que el Protocolo del Azúcar CE-ACP no ha funcionado como un verdadero instrumento de cooperación al desarrollo. Para recomendar cómo mejorar las relaciones comerciales CE-ACP sobre el azúcar, el trabajo econométrico realizado se ha complementado con el análisis del funcionamiento del mercado internacional del azúcar (especialmente en relación a los precios y a los flujos comerciales). Asimismo, se ha considerado la reforma de la Política Agrícola Común ante los cambios que implicará en el mercado europeo del azúcar. Todos estos elementos nos permiten sugerir dos opciones alternativas al Protocolo, permitidas en el Acuerdo de Cotonú, con vistas a dirigir la cooperación comercial CE-ACP sobre el azúcar desde 2008, momento en el que está prevista la progresiva aplicación de los Acuerdos de Asociación Económica (AAE) CE-ACP.Ambas opciones son compatibles con las normas de la Organización Mundial del Comercio y dependen de la decisión de cada Estado ACP respecto a la celebración de un AAE con la CE. Por un lado, para aquellos Estados ACP que decidan implementar un AAE, consideramos que el azúcar debería quedar cubierto en los esquemas resultantes de integración económica entre ambas Partes, lo que significa que se debería eliminar cualquier restricción que dificulte el comercio CE-ACP de azúcar. Por otro lado, en el caso de que algunos países ACP no alcancen un AAE con la Comunidad Europea, creemos que el azúcar tendría que formar parte del SPG mejorado de la CE, que será el trato comercial más probable que la CE ofrecerá a estos países ACP, como a los demás países en desarrollo. En cualquier caso, el proceso de cambio debería acompañarse de la concesión de ayuda financiera y técnica dirigida a dichos países ACP para ayudarlos a reestructurar el sector del azúcar y, en general, apoyarlos a que se adapten a las nuevas condiciones económicas de un mercado más globalizado. NOTA: Esta tesis recibió el "Premi Maspons i Anglasell" del "Patronat Català Pro Europa" (actualmente "Patronat Catalunya-Món") de la Generalitat de Catalunya a la mejor tesis doctoral en el bienio 2004-2005 (14a edición), el día 18 de abril de 2007. / IMPACT EVALUATION OF THE ACP-EC SUGAR PROTOCOL.In order to contribute in constructing the new trade co-operation between the European Community (EC) and the African, Caribbean and Pacific States (ACP), this thesis focuses in the current European access regime for agricultural products originating from the ACP Group. To be exact, it is carried out an analysis and evaluation of the ACP-EC Sugar Protocol (or, formally, Protocol 3 on ACP sugar) appearing the first time, in the ACP-EC Convention of Lomé signed on 28th February 1975. The principal reason for this particular co-operation instrument is that its provision is more beneficial than the other agricultural products Protocols. Thus, this commercial sugar agreement is the only one based on a purchase commitment from the EC and a sale commitment from the ACP beneficiary countries, of specified quantities, in the framework of a guaranteed high price -similar to the intervention price in the European sugar market-. In practice, this special trading agreement has implied substantial income transfers and a significant stability level of sugar export earnings for some of the ACP participant countries, especially those that presented historic sugar trading links with the United Kingdom. The final goal of this study consists of proposing if the ACP-EC Sugar Protocol has to be integrated in the EPAs or, on the contrary, it is better to keep it under the possible exclusion permitted in article XXIV of the General Agreement on Tariffs and Trade (GATT). This research also presents the option for the Sugar Protocol to be included in the EC's Generalised System of Preferences (GSP), even though tariff and non-tariff reductions, together with the specific exemptions, are less generous than those granted to European imports of ACP products. Within this aim, this study deals with an impact evaluation of the ACP-EC Sugar Protocol over economic development of ACP beneficiary countries. It demonstrates that the implicit income transfers by sugar companies from the ACP Sugar Group has not implied, in general, an economic welfare expansion for their economies. This outcome has been obtained using different econometric models: a linear regression model, an error correction model and a model with panel data. In consequence, we conclude that the ACP-EC Sugar Protocol has not functioned as a true development co-operation instrument.In order to recommend how to improve the ACP-EC trade relations on sugar, that econometric study has been complemented with an analysis of the international sugar market functioning (especially, referring to prices and commercial flows). The changes the Common Agriculture Policy reform will imply on the European sugar market have been considered as well. All of these items allow us to suggest the two alternative options to the Protocol, permitted in the Cotonou Agreement, in order to lead the ACP-EC trade co-operation on sugar since 2008. Both options are compatible with the World Trade Organisation rules and depend on the ACP State decision about the celebration of an EPA with the EC. On the one hand, for those ACP States that decide to implement an EPA, we consider that sugar should be covered in the resulting economic integration schemes between both parties, which means that any restriction on ACP-EC sugar trade should be eliminated. On the other hand, in the case that some ACP countries do not achieve an EPA with the EC, we believe that sugar should take part of the improved EC's GSP, which will be the most probable trade treatment that the EC will offer to those ACP States, as well as to the rest of developing countries. In both cases, the change process should be accompanied with the granting of financial and technical assistance to these ACP countries in order to help them to restructure the sugar sector and, in general, to support them to adjust to the new economic conditions within more globalised market. N.B.: Maspons i Anglasell Prize awarded by the Patronat Català Pro Europa (presently, Patronat Catalunya-Món) of la Generalitat (government institution) of Catalonia (Spain) for the best doctoral thesis in European integration for the biennium 2004-2005 (14th edition), 18 April of 2007.

La pile à combustible (PAC) est une technologie maintenant maîtrisée qui permet de convertir efficacement le combustible hydrogène en énergie électrique et thermique avec un faible impact environnemental. L'extension de son utilisation dépend fortement de la qualité de l'interface électronique de puissance qui a pour l'objet d'adapter la pile à la charge. Le travail de recherche présenté dans ce mémoire de Doctorat s'intéresse à la conception d'une interface électronique de puissance pour la pile à combustible pour les trois domaines d'applications : télécommunication, transport et stationnaire. <br />Dans cette objective, l'approche modulaire, qui se base sur l'étude des convertisseurs unitaires et leurs modes de connexion, a été proposée afin de s'adapter à la modularité des stacks de PAC. Des modèles de pertes et de dimensionnement des composants passifs et semi conducteurs ont été construits. La technique de l'entrelacement est introduite afin de résoudre le problème de fort courant et permet d'optimiser le dimensionnement des inductances. Une nouvelle structure nommée double BOOST dual entrelacé (Interleaved Double Dual BOOST – IDD BOOST) a été proposée afin de résoudre les difficultés d'un convertisseur modulaire présentant une tension de sortie élevée et un rapport de tension important. Les stratégies de contrôle – commande multi sources ont été étudié en adaptant aux topologies de l'interface de puissance. Deux prototypes ont été réalisés afin de valider les résultats de prédiction de pertes ainsi que le contrôle commande multi sources.

Nous étudions l'algorithmique de deux problèmes centraux d'Intelligence Artificielle, pour des bases de connaissances représentées, notamment, par des formules propositionnelles de Horn, bijonctives, Horn-renommables ou affines. Nous traitons tout d'abord l'acquisition de connaissances à partir d'exemples : nous donnons notamment un algorithme efficace et général pour l'acquisition exacte, complétons l'état de l'art pour l'approximation et donnons un algorithme pour le PAC-apprentissage des formules affines. Nous étudions ensuite des problèmes de raisonnement : nous donnons un algorithme général pour l'abduction, qui nous permet d'exhiber de nouvelles classes polynomiales, et posons de premières pierres pour l'étude de ce processus lorsque la base de connaissances est approximative. L'étude des formules affines pour la représentation de connaissances n'avait jamais été réellement menée. Les résultats présentés dans ce mémoire montrent qu'elles possèdent de nombreuses bonnes propriétés.