Durant les quatre dernières décennies, l’industrie des semi-conducteurs a connu une croissance exponentielle. En accord avec l’ITRS et à mesure de l'approche vers le nanomètre, les promesses sont énormes et les composants sont réduits à leurs limites physiques et économiques ultimes. L’objectif principal de cette thèse est d’explorer les opportunités offertes par les technologies émergentes pour la conception d’architectures reconfigurables. Tout d’abord, la thèse se centre sur l’architecture FPGA traditionnelle et étudie des améliorations structurelles apportées par des technologies en ruptures. Tandis que les structures de configuration et de routage occupent la majeure partie de la surface d’un FPGA et limitent ces performances, l’intégration 3-D apparait comme une bonne opportunité pour déplacer ces circuits dans les niveaux métalliques. Des circuits de configuration et de routage utilisant des mémoires résistives compatibles back-end, un procédé d’intégration 3-D ou encore un procédé de réalisation de transistors verticaux seront introduits et évalués dans un contexte architectural complet. Par la suite, la thèse présente de nouvelles propositions architecturales pour la logique à grain ultra-fin. La taille des éléments logiques peut être réduite grâce aux propriétés inhérentes de certaines technologies, telles que l’arrangement en structures entrecroisées de nanofils ou la polarité contrôlable des transistors carbones. Considérant le changement de granularité des opérateurs logiques, des topologies d’interconnexions fixes sont nécessaires afin d’éviter l’important surcoût dû à l’interconnexion programmable. Afin d’étudier les possibilités de cette organisation, un flot d’évaluation est présenté et utilisé pour explorer l’espace de conception relatif aux architectures à grain ultra-fin. / For the last four decades, the semiconductor industry has experienced an exponential growth. According to the ITRS, as we advance into the era of nanotechnology, the traditional CMOS electronics is reaching its physical and economical limits. The main objective of this thesis is to explore novel design opportunities for reconfigurable architectures given by the emerging technologies. On the one hand, the thesis will focus on the traditional FPGA architecture scheme, and survey some structural improvements brought by disruptive technologies. While the memories and routing structures occupy the major part of the FPGAs total area and mainly limit the performances, 3-D integration appears as a good candidate to embed all this circuitry into the metal layers. Configuration and routing circuits based on back-end compatible resistive memories, a monolithic 3-D process flow and a prospective vertical FETs process flow are introduced and assessed within a complete architectural context. On the other hand, the thesis will present some novel architectural schemes for ultra-fine grain computing. The size of the logic elements can be reduced thanks to inherent properties of the technologies, such as the crossbar organization or the controllable polarity of carbon electronics. Considering the granularity of the logic elements, specific fixed and incomplete interconnection topologies are required to prevent the large overhead of a configurable interconnection pattern. To evaluate the potentiality of this new architectural scheme, a specific benchmarking flow will be presented in order to explore the ultra-fine grain architectural design space.

Pas de résumé / Production of new neurons in the brain decreases dramatically with age due to progressive physiological depletion of stem and progenitor cell populations (NSCs). Recent studies indicate that circulating factors constitute a systemic aging milieu regulating the birth of new cells. Interestingly, some long-lived mouse strains such as Ames dwarf mutants, with low circulating levels of GH and IGF-1, show increased neurogenesis and preserved hematopoietic stem cell pool. Thus, the possibility that genes regulating lifespan and aging also quantitatively modulate stem cells in mammals is more and more explored. IGF-1 plays a pivotal role in aging in different species, and I am asking whether some of the well-known longevity effects resulting from down-regulation of this signaling pathway could be explained by local regulation of stem and progenitor cell compartments. To validate this hypothesis, I pursued a dual approach based on biological experiments and mathematical modeling. Using a novel triple transgenic mouse model, I inactivated IGF-1 signaling specifically in adult NSCs, and traced knockout cell lineages with a fluorescent reporter transgene. By analyzing the phenotype at different time points after KO induction, I could distinguish between short and long-term effects of IGF signaling on cellular regeneration and identify cumulative physiological consequences of down-regulation of this pathway using behavioral tests. In my mathematical models, the dynamics of regenerative cell populations were described by a set of differential equations depending on circulating “growth-factor like molecules” (GFs). My results suggest that in aging tissues, the optimal distribution of GFs is a function that decreases with time. In the olfactory system, I showed that inactivation of IGF signaling in adult NSCs enhanced long-term maintenance of neuroblasts and increased the overall production of neurons. Mutants started with the same number of adult-born neurons as controls one month after KO induction at 4 months of age, but ended up having significantly more differentiated cells integrating the olfactory bulb at long-term, i.e. at 16 months of age. This highly increased neurogenic activity occurred without depletion of neural stem/progenitor cell compartments. In contrast, IGF-1R deletion in adult hippocampal stem cells did not change neurogenesis dynamics, pointing out a niche-dependent effect of IGFs. The important cellular changes in the olfactory bulb led to improved olfactory memory and odor discrimination in aged mutants. Strikingly, mutants also displayed altered energy homeostasis and increased sensitivity to metabolic hormones, namely leptin and insulin. This metabolic shift could be linked to enhanced olfactory function, and to changes in hypothalamic neurogenesis. Indeed, we observed that IGF-1R deletion in hypothalamic stem cells (HySC) protected α-tanycyte pool from age-related decline and increased the number of newborn neurons in the hypothalamus. Taken together, my results validate the hypothesis that life-long inhibition of IGF signaling in adult NSCs delays age-related decline of neurogenesis, in a niche-dependent manner. These data also show that local modulation of neural cell replacement has important physiological effects at the level of the whole organism, pointing out a novel pathophysiological role for adult neurogenesis.

In recent years, the power industry has experienced significant changes on the distribution power system primarily due to the implementation of smart-grid technology and the incremental implementation of distributed generation. Distributed Generation (DG) is simply defined as the decentralization of power plants by placing smaller generating units closer to the point of consumption, traditionally ten mega-watts or smaller. While DG is not a new concept, DG is gaining widespread interest primarily for the following reasons: increase in customer demand, advancements in technology, economics, deregulation, environmental and national security concerns. The distribution power system traditionally has been designed for radial power flow, but with the introduction of DG, the power flow becomes bidirectional. As a result, conventional power analysis tools and techniques are not able to properly assess the impact of DG on the electrical system. The presence of DG on the distribution system creates an array of potential problems related to safety, stability, reliability and security of the electrical system. Distributed generation on a power system affects the voltages, power flow, short circuit currents, losses and other power system analysis results. Whether the impact of the DG is positive or negative on the system will depend primarily on the location and size of the DG. The objective of this research is to develop indices and an effective technique to evaluate the impact of distributed generation on a distribution power system and to employ the particle swarm optimization technique to determine the optimal placement and size of the DG unit with an emphasis on improving system reliability while minimizing the following system parameters: power losses, voltage deviation and fault current contributions. This research utilizes the following programs to help solve the optimal DG placement problem: Distribution System Simulator (DSS) and MATLAB. The developed indices and PSO technique successfully solved the optimal DG sizing and placement problem for the I 13-Node, 34-Node and 123-Node Test Cases. The multi-objective index proved to be computational efficient and accurately evaluated the impact of distributed generation on the power system. The results provided valuable information about the system response to single and multiple DG units.

This thesis presents a method, Ensemble Kalman Filter (EnKF), applied to a highresolution, shallow water equations model (DG ADCIRC-2DDI) of the Lower St. Johns River with observation data at four gauging stations. EnKF, a sequential data assimilation method for non-linear problems, is developed for tidal flow simulation for estimation of state variables, i.e., water levels and depth-integrated currents for overland unstructured finite element meshes. The shallow water equations model is combined with observation data, which provides the basis of the EnKF applications. In this thesis, EnKF is incorporated into DG ADCIRC-2DDI code to estimate the state variables. Upon its development, DG ADCIRC-2DDI with EnKF is first validated by implementing to a low-resolution, shallow water equations model of a quarter annular harbor with synthetic observation data at six gauging stations. Second, DG ADCIRC-2DDI with EnKF is implemented to a high-resolution, shallow water equations model of the Lower St. Johns River with real observation data at four gauging stations. Third, four different experiments are performed by applying DG ADCIRC-2DDI with EnKF to the Lower St. Johns River.

No description available.

Dans les années à venir, l’industrie de la microélectronique doit développer de nouvelles filières technologiques qui pourront devenir des successeurs ou des compléments de la technologie CMOS ultime. Parmi ces technologies émergentes relevant du domaine ‘‘Beyond CMOS’’, ce travail de recherche porte sur les transistors mono-électroniques (SET) dont le fonctionnement est basé sur la quantification de la charge électrique, le transport quantique et la répulsion Coulombienne. Les SETs doivent être étudiés à trois niveaux : composants, circuits et système. Ces nouveaux composants, utilisent à leur profit le phénomène dit de blocage de Coulomb permettant le transit des électrons de manière séquentielle, afin de contrôler très précisément le courant véhiculé. Ainsi, le caractère granulaire de la charge électrique dans le transport des électrons par effet tunnel, permet d’envisager la réalisation de transistors et de cellules mémoires à haute densité d’intégration, basse consommation. L’objectif principal de ce travail de thèse est d’explorer et d’évaluer le potentiel des transistors mono-électroniques double-grille métalliques (DG-SETs) pour les circuits logiques numériques. De ce fait, les travaux de recherches proposés sont divisés en trois parties : i) le développement des outils de simulation et tout particulièrement un modèle analytique de DG-SET ; ii) la conception de circuits numériques à base de DGSETs dans une approche ‘‘cellules standards’’ ; et iii) l’exploration d’architectures logiques versatiles à base de DG-SETs en exploitant la double-grille du dispositif. Un modèle analytique pour les DG-SETs métalliques fonctionnant à température ambiante et au-delà est présenté. Ce modèle est basé sur des paramètres physiques et géométriques et implémenté en langage Verilog-A. Il est utilisable pour la conception de circuits analogiques ou numériques hybrides SET-CMOS. A l’aide de cet outil, nous avons conçu, simulé et évalué les performances de circuits logiques à base de DG-SETs afin de mettre en avant leur utilisation dans les futurs circuits ULSI. Une bibliothèque de cellules logiques, à base de DG-SETs, fonctionnant à haute température est présentée. Des résultats remarquables ont été atteints notamment en terme de consommation d’énergie. De plus, des architectures logiques telles que les blocs élémentaires pour le calcul (ALU, SRAM, etc.) ont été conçues entièrement à base de DG-SETs. La flexibilité offerte par la seconde grille du DG-SET a permis de concevoir une nouvelle famille de circuits logiques flexibles à base de portes de transmission. Une réduction du nombre de transistors par fonction et de consommation a été atteinte. Enfin, des analyses Monte-Carlo sont abordées afin de déterminer la robustesse des circuits logiques conçus à l'égard des dispersions technologiques. / In this work, we have presented a physics-based analytical SET model for hybrid SET-CMOS circuit simulations. A realistic SET modeling approach has been used to provide a compact SET model that takes several conduction mechanisms into account and closely matches experimental SET characteristics. The model is implemented in Verilog-A language, and can provide suitable environment to simulate hybrid SET-CMOS architectures. We have presented logic circuit design technique based on double gate metallic SET at room temperature. We have also shown the flexibility that the second gate can bring in order to configure the SET into P-type and N-type. Given that the same device is utilized, the circuit design approach exhibits regularity of the logic gate that simplifies the design process and leads to reduce the increasing process variations. Afterwards, we have addressed a new Boolean logic family based on DG-SET. An evaluation of the performance metrics have been carried out to quantify SET technology at the circuit level and compared to advanced CMOS technology nodes. SET-based static memory was achieved and performances metrics have been discussed. At the architectural level, we have investigated both full DG-SET based arithmetic logic blocks (FA and ALU) and programmable logic circuits to emphasize the low power aspect of the technology. The extra power reduction of SETs based logic gates compared to the CMOS makes this technology much attractive for ultra-low power embedded applications. In this way, architectures based on SETs may offer a new computational paradigm with low power consumption and low voltage operation. We have also addressed a flexible logic design methodology based on DG-SET transmission gates. Unlike conventional design approach, the XOR / XNOR behavior can be efficiently implemented with only 4 transistors. Moreover, this approach allows obtaining reconfigurable XOR / XNOR gates by swapping the cell biasing. Given that the same device is utilized, the structure can be physically implemented and established in a regular manner. Finally, complex logic gates based on DG-SET transmission gates offer an improvement in terms of transistor device count and power consumption compared to standard complementary SETs implementations.Process variations are introduced through our model enabling then a statistical study to better estimate the SET-based circuit performances and robustness. SET features low power but limited operating frequency, i.e. the parasitics linked to the interconnects reduce the circuit operating frequency as the SET Ion current is limited to the nA range. In term of perspectives: i) detailed studying the impact on SET-based logic cells of process variation and random back ground charge ii) considering multi-level computational model and their associate architectures iii) investigating new computation paradigms (neuro-inspired architectures, quantum cellular automata) should be considered for future works.

Dans [PRID], Pridham a montré que tout n-champs d'Artin M admet une présentation en tant que schéma simplicial X. → M, telle que le schéma simplicial X satisfait à certaines propriétés notées par G.Pn,k de [GROTH]. Dans la présentation (…→ X2 → X1 → X0 → M), le schéma X1 représente une carte pour X0 x MX0. Donc, la lissité de X0 → M est équivalente à la lissité des deux projections ә0,ә1 : X1 → X0. Ce sont les deux premières parties de la condition de Grothendieck-Pridham, notées G.P1,0 et G.P1,1. Dans [BENZ12] nous avons introduit un n-champ d'Artin M des éléments de Maurer-Cartan d'une dg-catégorie. On a construit une carte, et on a déjà fait la preuve des premières conditions de lissité explicitement. Pour tout n et tout 0 ≤ k ≤ n Pridham considère un schéma noté MatchΛkn(X) avec un morphisme Xn → MatchΛkn(X). On construira explicitement le schéma simplicial de Grothendieck-Pridham X, on montrera la lissité formelle de cette carte précédente, ainsi que M est un n-champ géométrique. / In [PRID], Pridham has shown that any Artin n-stack M has a presentation as a simplicial scheme X. → M such that the simplicial scheme X satisfies certain properties denoted G.Pn,k of [GROTH]. In the presentation (…→ X2 → X1 → X0 → M), the scheme X1 represents a chart for X0 x MX0. Thus, the smoothness of X0 → M is equivalent to the smoothness of the two projections ә0,ә1 : X1 → X0. These are the first two parts of the Grothendieck-Pridham condition, denoted G.P1,0 and G.P1,1. In [BENZ12] we introduced an Artin n-stack M of Maurer-Cartan elements of a dg-category. We constructed a chart, and have already proven the first smoothness conditions explicitly. For any n and any 0 ≤ k ≤ n Pridham considers a scheme denoted MatchΛkn(X) with a morphism Xn → MatchΛkn(X). We will construct explicitly the Grothendieck-Pridham simplicial scheme and show the smoothness of the preceding map, therefore M is a geometric n-stack.

We analyze a number of systems of evolution equations that arise in the study of physical chemistry. First we discuss the well-posedness of a system of mixing compressible barotropic multicomponent flows. We discuss the regularity of these variational solutions, their existence and uniqueness, and we analyze the emergence of a novel type of entropy that is derived for the system of equations. Next we present a numerical scheme, in the form of a discontinuous Galerkin (DG) finite element method, to model this compressible barotropic multifluid. We find that the DG method provides stable and accurate solutions to our system, and that further, these solutions are energy consistent; which is to say that they satisfy the classical entropy of the system in addition to an additional integral inequality. We discuss the initial-boundary problem and the existence of weak entropy at the boundaries. Next we extend these results to include more complicated transport properties (i.e. mass diffusion), where exotic acoustic and chemical inlets are explicitly shown. We continue by developing a mixed method discontinuous Galerkin finite element method to model quantum hydrodynamic fluids, which emerge in the study of chemical and molecular dynamics. These solutions are solved in the conservation form, or Eulerian frame, and show a notable scale invariance which makes them particularly attractive for high dimensional calculations. Finally we implement a wide class of chemical reactors using an adapted discontinuous Galerkin finite element scheme, where reaction terms are analytically integrated locally in time. We show that these solutions, both in stationary and in flow reactors, show remarkable stability, accuracy and consistency. / text

Estudos convencionais de identificacao e de viabilidade de potenciais de producao de energia eletrica eolica e hidroeletrica de pequena escala demandam trabalhos de campo que, muitas vezes, implicam na inviabilidade economica do negocio em funcao dos seus onerosos custos. Alem disso, a execucao desses trabalhos nao assegura ao investidor a recuperacao desses onerosos recursos despendidos, principalmente se o potencial estudado apresentar inviabilidade tecnico-economica. Acrescenta-se ainda a esse risco, a possibilidade do investidorexecutor dos estudos iniciais (estimativa e inventario/viabilidade) nao contrair a outorga de exploracao do potencial, que e oferecida publicamente pelo Orgao Regulador. Entretanto, esse risco pode ser mitigado com a indicacao orientativa de viabilidade, com custos reduzidos. Por outro lado, ha uma forte tendencia de implantacao de pequenas centrais de producao de energia, caracterizadas como \"Geracao Distribuida\" (GD), em virtude dos atuais incentivos regulatorios para essas fontes, das recentes restricoes ambientais e da escassez de investimentos em grandes projetos. Neste contexto, esta dissertacao apresenta um modelo de obtencao de pre-viabilidade de potenciais fundamentado em caracteristicas tecnicas de componentes de Usinas Eolicas (EOL\'s) e Pequenas Centrais Hidreletricas (PCH\'s), com atributos fisicos geograficamente representados e consultados em um ambiente de geoprocessamento informatizado. Esse modelo proposto realiza estimativa de indicadores tecnico-economicos de centrais, produzindo estudos de pre-viabilidade com rapidez e baixo custo. De posse desse modelo o investidor pode simular a implementacao de varios aproveitamentos eolicos e hidroeletricos, antes de mobilizacao e de levantamentos de campo mais precisos e onerosos, obtendo dessa forma orientacoes importantes para direcionar sua atencao, com minimizacao de incertezas envolvidas na pre-viabilidade do potencial. / Identification and viability studies on small scale production of electrical energy based on wind and hydro power conventionally demand onerous field work whose costs frequently imply economic unfeasibility of the business. Moreover, the execution of these works does not assure that the investor will recover its expended resources, mainly if the potential analysis of the business demonstrates its technical and economic unfeasibility. Additionally, there is the possibility of not contracting the concession to this potential exploration, which is publicly offered by the Regulatory Agency, by the investor-executor of the initial studies (estimative, inventory and viability). However, this risk can be mitigated by the guiding indication of viability, with reduced costs. On the other hand, it has one strong trend of implantation of smallscale power generation, characterized as \"Distributed Generation\" (DG), because of its current legal incentives and also because of the recent ecological restrictions and the scarcity of investments in large enterprises. In this context, this work presents a pre-viability of potentials attainment model based on technical characteristics of Wind Plants and Small Hydroelectric Plants (SHP\'s) components, whose physical attributes are geographically represented and consulted in a geographic information system. The proposed model estimates the technical and economical pointers of power plants, producing fast and low-cost studies of pre-viability. Trough this model the investor can simulate wind power and hydropower exploration before mobilizating onerous and accurate field researches, getting an important guiding to its priorities, minimizing uncertainties in the process.

Estudos convencionais de identificacao e de viabilidade de potenciais de producao de energia eletrica eolica e hidroeletrica de pequena escala demandam trabalhos de campo que, muitas vezes, implicam na inviabilidade economica do negocio em funcao dos seus onerosos custos. Alem disso, a execucao desses trabalhos nao assegura ao investidor a recuperacao desses onerosos recursos despendidos, principalmente se o potencial estudado apresentar inviabilidade tecnico-economica. Acrescenta-se ainda a esse risco, a possibilidade do investidorexecutor dos estudos iniciais (estimativa e inventario/viabilidade) nao contrair a outorga de exploracao do potencial, que e oferecida publicamente pelo Orgao Regulador. Entretanto, esse risco pode ser mitigado com a indicacao orientativa de viabilidade, com custos reduzidos. Por outro lado, ha uma forte tendencia de implantacao de pequenas centrais de producao de energia, caracterizadas como \"Geracao Distribuida\" (GD), em virtude dos atuais incentivos regulatorios para essas fontes, das recentes restricoes ambientais e da escassez de investimentos em grandes projetos. Neste contexto, esta dissertacao apresenta um modelo de obtencao de pre-viabilidade de potenciais fundamentado em caracteristicas tecnicas de componentes de Usinas Eolicas (EOL\'s) e Pequenas Centrais Hidreletricas (PCH\'s), com atributos fisicos geograficamente representados e consultados em um ambiente de geoprocessamento informatizado. Esse modelo proposto realiza estimativa de indicadores tecnico-economicos de centrais, produzindo estudos de pre-viabilidade com rapidez e baixo custo. De posse desse modelo o investidor pode simular a implementacao de varios aproveitamentos eolicos e hidroeletricos, antes de mobilizacao e de levantamentos de campo mais precisos e onerosos, obtendo dessa forma orientacoes importantes para direcionar sua atencao, com minimizacao de incertezas envolvidas na pre-viabilidade do potencial. / Identification and viability studies on small scale production of electrical energy based on wind and hydro power conventionally demand onerous field work whose costs frequently imply economic unfeasibility of the business. Moreover, the execution of these works does not assure that the investor will recover its expended resources, mainly if the potential analysis of the business demonstrates its technical and economic unfeasibility. Additionally, there is the possibility of not contracting the concession to this potential exploration, which is publicly offered by the Regulatory Agency, by the investor-executor of the initial studies (estimative, inventory and viability). However, this risk can be mitigated by the guiding indication of viability, with reduced costs. On the other hand, it has one strong trend of implantation of smallscale power generation, characterized as \"Distributed Generation\" (DG), because of its current legal incentives and also because of the recent ecological restrictions and the scarcity of investments in large enterprises. In this context, this work presents a pre-viability of potentials attainment model based on technical characteristics of Wind Plants and Small Hydroelectric Plants (SHP\'s) components, whose physical attributes are geographically represented and consulted in a geographic information system. The proposed model estimates the technical and economical pointers of power plants, producing fast and low-cost studies of pre-viability. Trough this model the investor can simulate wind power and hydropower exploration before mobilizating onerous and accurate field researches, getting an important guiding to its priorities, minimizing uncertainties in the process.