Cette thèse contribue à la littérature sur les normes prudentielles de la gestion des risques bancaires,la causalité entre le développement financier et la croissance économique et enfin les hypothèses del'aléa moral et de la réglementation du capital des banques. La crise des Subprimes de 2007 aparadoxalement permis de souligner une fois de plus les lacunes des normes prudentielles Bâle I etBâle II, du fait de ses différentes conséquences sur les systèmes bancaires mondiaux. En adoptantune démarche économétrique et en exploitant des données de panel sur un échantillon des banquesd’Afrique subsaharienne et du Maghreb, nous avons utilisé plus particulièrement la technique decausalité au sens de Granger et celle d'estimation GMM afin de mener des études empiriques surcelles-ci, notamment la causalité entre le développement financier et l’économie réelle d’une part, larelation entre le capital et la profitabilité (risque) des banques d’autre part. Les résultats soulignent ladépendance entre certaines variables de la profitabilité des banques et la croissance économiqued’une part, et d’autre part les comportements des banques africaines, en termes de la détention ducapital et à la prise excessive des risques, cadrent parfaitement aux hypothèses de l’aléa moral et dela réglementation du capital du comité de Bâle. / This thesis contributes to the literature on prudential risk management in the banking sector,causality between financial development and economic growth and finally, the study of moral hazardand the regulation of the capital of banks. The Subprime Mortgage Crisis of 2007 paradoxicallyDépôt de thèseDonnées complémentairesmade it possible to once more highlight the inadequacies in the Basel I and Basel II prudentialstandards, because of its various consequences on the global financial system. We adopted andapplied the Granger causality test and the GMM estimation method to panel data on a sample ofbanks in sub-Saharan Africa and the Middle East, in order to conduct empirical studies, in particularon the causality between financial development and the real economy on one hand, the relationbetween capital and the profitability (risk) of banks on the other. The results highlight thedependence between certain variables describing bank profitability and economic growth on onehand, and those describing the characteristics of African banks on the other, in terms of capitalretention and excessive risk taking. This coincides perfectly with the study of moral hazard andcapital regulation set by the Basel Committee.

The introduction of the European Union (EU) macro-regional strategies (MRS) in the latter half of the 2000s was a significant step in the process of transformation of EU governance system. EU MRSs act as a new form of comprehensive governance framework for multi-objective and cross-sectoral cooperation in geographically defined macro-regions. This thesis examines the case of the Baltic Sea Region in order to evaluate a potential of this new governance instrument to transform cooperation arrangements in the region. In order to shed light on the strategy’s patterns and dynamics, the present study utilizes a qualitative methodological approach that uses document analysis based on a comprehensive analytical framework. The analytical framework incorporates the theoretical perspectives of multi-level and experimentalist governance, as well as the theory of differentiated integration. The main findings of this study suggest that the inception of the EU Strategy for the Baltic Sea Region (EUSBSR) in 2009 has offered an innovative and dynamic framework for cooperation that enabled a wider representation and more active participation of local and regional actors. This allowed for a more coherent and coordinated policymaking, facilitated a more responsive and transparent cooperation system in the region, as well as fostered transnational cooperation in the Baltic Sea Region by ensuring a wider engagement of non-EU countries.

I dagsläget använder allt fler företag influencer marketing, i form av betalda samarbeten, för att marknadsföra sina produkter och tjänster. Influencers kan idag skapa unika och framgångsrika varumärken på sociala medier. Företag använder både micro- och macro-influencers, men det saknas forskning kring hur den upplevda trovärdigheten är till dessa. Uppsatsen undersöker konsumenters upplevda trovärdighet gentemot små respektive stora influencers på plattformen Instagram. För att analysera konsumenters upplevda trovärdighet tillämpas Ohanian (1990) Source Credibility (SC) modell. Empirin består av 15 djupgående semistrukturerade intervjuer med unga kvinnor i åldrarna 21–26. För att uppnå studiens syfte har empirin analyserats i relation till tidigare forskning och teori. Uppsatsen behandlar områden som influencer marketing, Instagram samt trovärdighet i teorin och tidigare forskning. Studiens slutsats är att macro-influencers uppfattas som mer trovärdiga än micro-influencers. Resultatet visade att även andra faktorer än influencers följarantal spelade in. Betalda samarbeten, som speglade en genuinitet och transparens och även ett uppvisande av en allsidig personlighet, var de främsta faktorerna som visade sig vara avgörande för den upplevda trovärdigheten. Resultaten i denna studie antyder även att de olika begreppen, med utgångspunkt i Source Credibility modellen, visade olika resultat. Macro-influencers ansågs som mer pålitliga, tillförlitliga och trovärdiga, medan micro-influencers ansågs som mer uppriktiga och ärliga. Det finns således fördelar att använda sig av båda inriktningarna av influencers. Valet bör dock betraktas noga beroende på vad företagen vill kommunicera. För att ett företag ska kunna göra rätt val vid användningen av influencers bör de vara medvetna om dessa skillnader mellan micro- och macro-influencers. / Today, companies are increasingly using influencer marketing, in the form of paid collaborations, to market their products and services. Influencers can create unique and successful brands on social media. Companies use both micro- and macro-influencers, but there is a gap in the existing research where influencers with different numbers of followers in relation to credibility are studied. Therefore, this study examines consumers' perceived credibility towards small and large influencers on the platform Instagram. This is investigated by analyzing consumers' perceptions of influencers with different numbers of followers. To analyze consumers' perceptions, the Ohanian (1990) Source Credibility (SC) model is applied. The empiric material consists of 15 in-depth semi-structured interviews with young women in the ages 21-26. To achieve the purpose of the study, the empirical data have been analyzed in relation to previous research and theory. The thesis deals with areas such as influencer marketing, Instagram and credibility in theory and previous research. The study concludes that macro-influencers are perceived as more credible than micro-influencers. The results indicated that factors other than influencers' quantity of followers also were important. Paid collaborations reflected by a genuineness and transparency and also a display of a multifaceted personality proved to be crucial for credibility. The results of this study also suggest that the different concepts, based on the Source Credibility Model, indicated different results. Macro-influencers were considered more reliable, trustworthy and credible, while micro-influencers were considered more sincere and honest. Thus, there are advantages to using both parts of influencers. However, the choice should be carefully reviewed depending on what the companies want to communicate. In order for a company to be able to make the right choice of the use of influencers, companies should be aware of these differences between micro- and macro-influencers.

This article examines the effects of participation in transitional justice rituals. Truth Commissions and trials have instrumental goals of distributive justice, and serve as rituals given their marked symbolic character, helping to achieve reconciliation and the reconstruction of social norms. Evidence suggests that participation in trials increases negative emotion and negative emotional climate. However participants in such rituals have evidenced increased empowerment, despite conditions of limited justice and reparation. Moreover, participation in Gacaca or popular trials in Rwanda, decreases shame in victims, and decreases negative stereotypes and increases individualization of out-groups. Finally, a collective analysis of 16 Latin America nations found that trials and a successful Truth Commission reinforces respect for human rights. / El análisis de las experiencias de la Comisión de la Verdad y la Reconciliación en Sudáfrica, los juicios populares o Gacaca en Ruanda y los rituales de los procesos de transición a la democracia concluye que la participación en comisiones y juicios implica un coste emocional para los participantes (aumenta la emocionalidad negativa y los síntomas) y aumenta el clima emocional negativo en la sociedad, pero también aumenta la sensación de control y eficacia de los participantes, disminuye algunas emociones negativas en los sobrevivientes como la vergüenza, y aumenta los estereotipos positivos y una visión más diferenciada del exogrupo. En países de América Latina donde se han desarrollado procesos y comisiones de verdad más eficaces, se constató una mejora del respeto a los derechos humanos.

A Coarse-Grained Reconfigurable Architecture (CGRA) is a processing platform which constitutes an interconnection of coarse-grained computation units (viz. Function Units (FUs), Arithmetic Logic Units (ALUs)). These units communicate directly, viz. send-receive like primitives, as opposed to the shared memory based communication used in multi-core processors. CGRAs are a well-researched topic and the design space of a CGRA is quite large. The design space can be represented as a 7-tuple (C, N, T, P, O, M, H) where each of the terms have the following meaning: C -choice of computation unit, N -choice of interconnection network, T -Choice of number of context frame (single or multiple), P -presence of partial reconfiguration, O choice of orchestration mechanism, M -design of memory hierarchy and H host-CGRA coupling. In this thesis, we develop an architectural framework for a Macro-Dataflow based CGRA where we make the following choice for each of these parameters: C -ALU, N -Network-on-Chip (NoC), T -Multiple contexts, P -support for partial reconfiguration, O -Macro Dataflow based orchestration, M -data memory banks placed at the periphery of the reconfigurable fabric (reconfigurable fabric is the name given to the interconnection of computation units), H -loose coupling between host processor and CGRA, enabling our CGRA to execute an application independent of the host-processor’s intervention. The motivations for developing such a CGRA are: To execute applications efficiently through reduction in reconfiguration time (i.e. the time needed to transfer instructions and data to the reconfigurable fabric) and reduction in execution time through better exploitation of all forms of parallelism: Instruction Level Parallelism (ILP), Data Level Parallelism (DLP) and Thread/Task Level Parallelism (TLP). We choose a macro-dataflow based orchestration framework in combination with partial reconfiguration so as to ease exploitation of TLP and DLP. Macro-dataflow serves as a light weight synchronization mechanism. We experiment with two variants of the macro-dataflow orchestration units, namely: hardware controlled orchestration unit and the compiler controlled orchestration unit. We employ a NoC as it helps reduce the reconfiguration overhead. To permit customization of the CGRA for a particular domain through the use of domain-specific custom-Intellectual Property (IP) blocks. This aids in improving both application performance and makes it energy efficient. To develop a CGRA which is completely programmable and accepts any program written using the C89 standard. The compiler and the architecture were co-developed to ensure that every feature of the architecture could be automatically programmed through an application by a compiler. In this CGRA framework, the orchestration mechanism (O) and the host-CGRA coupling (H) are kept fixed and we permit design space exploration of the other terms in the 7-tuple design space. The mode of compilation and execution remains invariant of these changes, hence referred to as a framework. We now elucidate the compilation and execution flow for this CGRA framework. An application written in C language is compiled and is transformed into a set of temporal partitions, referred to as HyperOps in this thesis. The macro-dataflow orchestration unit selects a HyperOp for execution when all its inputs are available. The instructions and operands for a ready HyperOp are transferred to the reconfigurable fabric for execution. Each ALU (in the computation unit) is capable of waiting for the availability of the input data, prior to issuing instructions. We permit the launch and execution of a temporal partition to progress in parallel, which reduces the reconfiguration overhead. We further cut launch delays by keeping loops persistent on fabric and thus eliminating the need to launch the instructions. The CGRA framework has been implemented using Bluespec System Verilog. We evaluate the performance of two of these CGRA instances: one for cryptographic applications and another instance for linear algebra kernels. We also run other general purpose integer and floating point applications to demonstrate the generic nature of these optimizations. We explore various microarchitectural optimizations viz. pipeline optimizations (i.e. changing value of T ), different forms of macro dataflow orchestration such as hardware controlled orchestration unit and compiler-controlled orchestration unit, different execution modes including resident loops, pipeline parallelism, changes to the router etc. As a result of these optimizations we observe 2.5x improvement in performance as compared to the base version. The reconfiguration overhead was hidden through overlapping launching of instructions with execution making. The perceived reconfiguration overhead is reduced drastically to about 9-11 cycles for each HyperOp, invariant of the size of the HyperOp. This can be mainly attributed to the data dependent instruction execution and use of the NoC. The overhead of the macro-dataflow execution unit was reduced to a minimum with the compiler controlled orchestration unit. To benchmark the performance of these CGRA instances, we compare the performance of these with an Intel Core 2 Quad running at 2.66GHz. On the cryptographic CGRA instance, running at 700MHz, we observe one to two orders of improvement in performance for cryptographic applications and up to one order of magnitude performance degradation for linear algebra CGRA instance. This relatively poor performance of linear algebra kernels can be attributed to the inability in exploiting ILP across computation units interconnected by the NoC, long latency in accessing data memory placed at the periphery of the reconfigurable fabric and unavailability of pipelined floating point units (which is critical to the performance of linear algebra kernels). The superior performance of the cryptographic kernels can be attributed to higher computation to load instruction ratio, careful choice of custom IP block, ability to construct large HyperOps which allows greater portion of the communication to be performed directly (as against communication through a register file in a general purpose processor) and the use of resident loops execution mode. The power consumption of a computation unit employed on the cryptography CGRA instance, along with its router is about 76mW, as estimated by Synopsys Design Vision using the Faraday 90nm technology library for an activity factor of 0.5. The power of other instances would be dependent on specific instantiation of the domain specific units. This implies that for a reconfigurable fabric of size 5 x 6 the total power consumption is about 2.3W. The area and power ( 84mW) dissipated by the macro dataflow orchestration unit, which is common to both instances, is comparable to a single computation unit, making it an effective and low overhead technique to exploit TLP.

<p align="justify"><i>Typologie des cours d’eau en Wallonie et caractérisation par la faune invertébrée</i><br>Vingt-cinq types de cours d’eau ont été définis en Wallonie d’après les termes de la Directive Cadre pour l’Eau en tenant compte des facteurs obligatoires et optionnels rassemblés sous trois critères : la taille (du « ruisseau » à la « très grande rivière »), la pente (faible, moyenne et forte), et cinq régions naturelles (la région limoneuse, le Condroz, la Famenne, l’Ardenne et la Lorraine belge, résumant les facteurs obligatoires altitude, latitude, longitude et géologie). Une approche par analyses multivariées appliquées à un grand nombre d’échantillons (listes taxonomiques) a permis de définir de façon plus précise certains types de rivières et de distinguer sept groupes typologiques montrant des assemblages faunistiques similaires.</p> <p align="justify"><i>Conditions de référence types et définition de l’état écologique des rivières en Wallonie à l’aide de métriques biocénotiques basées sur les invertébrés</i><br> Les listes faunistiques et les valeurs métriques de l’IBGN (Indice biologique global normalisé) issues du réseau d’évaluation de la qualité biologique en Wallonie ont été utilisées pour discriminer les types de rivières et pour définir les sites de référence, les conditions de référence et les limites des classes des états écologiques. Au sud du sillon Sambre et Meuse, impliquant quatre groupes typologiques de rivières, les valeurs de référence et la définition des états écologiques ont été basées et calculées sur un réseau de référence de sites de très bon état. Les « valeurs de conditions de référence » ont été définies par les médianes des métriques des sites de « très bon état ». Lorsque aucun site de très bon état n’était disponible, c’est-à-dire pour les groupes typologiques au nord du sillon Sambre et Meuse et pour la Meuse et la Sambre, les conditions de référence (ou le « potentiel écologique maximal ») et les limites de classes ont été basées sur des coefficients appliqués aux sites de « bon état » et sur jugement d’expert.</p> <p align="justify"><i>Exercice pilote d’inter-étalonnage</i><br> Cinquante échantillons ont été sélectionnés parmi les rivières du type d’inter-étalonnage européen R-C3 (petite taille, altitude moyenne, substrat siliceux) en Wallonie (correspondant aux « ruisseaux ardennais ») dans toute la gamme de qualités écologiques, du « très bon » au « mauvais » état. Chaque métrique de l’indice « Intercalibration Common Metrics » (ICM) a été comparée (par régression linéaire et polynomiale) aux valeurs de l’IBGN. La plus forte corrélation a été établie avec l’indice synthétique de l’ICM dont le R² très élevé (0,95) permet un inter-étalonnage précis et fiable. A un EQR (Equivalent Quality Ratio) de l’IBGN = 1 correspond un indice ICM très proche (= 1,004). En conséquence, la métrique « cote de l’IBGN » est proposée comme métrique pour l’évaluation de l’état écologique de la faune invertébrée en Wallonie.</p> <p align="justify"><i>Espèces exotiques et invasives</i><br>L’ouverture récente du canal à grand gabarit Main – Danube en 1992 et la navigation qui en résulte a permis à plusieurs espèces de macroinvertébrés ponto-caspiennes d’envahir successivement les bassins du Rhin et de la Meuse. De 1998 à 2000, le réseau de mesure a enregistré quatre nouvelles espèces exotiques dans la Meuse en Belgique : une polychète (<i>Hypania invalida</i>) et trois crustacés (<i>Hemimysis anomala, Dikerogammarus villosus, D. haemobaphes</i>). Peu avant, en 1995, le bivalve asiatique <i>Corbicula fluminea</i> et l’amphipode nord-américain <i>Crangonyx pseudogracilis</i> ont également été enregistrés pour la première fois. La dynamique des invasions a été étudiée et discutée.</p> <p align="justify">L’<i>état biologique actuel</i> (2000-2002) des masses d’eaux de surface en Wallonie et l’évolution des états biologiques sur une décennie (1990-2002) figurent dans l’étude et sont discutés. Une amélioration globale de la qualité de 6 % est enregistrée pour cette période. L’amélioration de la qualité se manifeste principalement pour les états « mauvais » et « médiocre » s’élevant à l’état « moyen ».</p> <b>Abstract</b> <p align="justify"><i>River typology in Wallonia and invertebrate fauna characterization</i><br>Twenty-five river-types in Wallonia were defined according to the Water Framework Directive taking into account obligatory and optional factors gathered in three criteria: the size (from “brook” to “very large river”), the slope (gentle, medium and strong) and five natural regions (Loess, Condroz, Famenne, Arden and Jurassic summarising the obligatory altitude, latitude, longitude and geology factors). A multivariate approach applied to a large amount of samples (i.e. taxa lists) led to give a more accurate definition of some river-types and to discriminate seven river-type groups exhibiting similar faunal assemblages.</p> <p align="justify"><i>Type-specific reference conditions and ecological status definition of rivers in Wallonia using invertebrate biocenotic metrics</i><br> Faunal lists and IBGN (i.e. "Standardized Global Biological Index IBGN") metric values, evolving from the biological quality assessment network in Wallonia, were used to discriminate the river types and to define the reference sites, the reference conditions and the status class limits. South of the axis made by the Sambre & Meuse Rivers, involving four river-type groups, reference values and ecological status definition were based and calculated on a reference network of sites of high status. The "reference condition values” were defined as the median values of the metrics in all “high status” sites. Where no site of high status was available, i.e. in the others river-type groups north of the same axis and in the Rivers Sambre and Meuse themselves, reference conditions (or maximum ecological potential) and class limits were based on coefficients applied to “good status” sites and on expert judgement.</p> <p align="justify"><i>Intercalibration pilot exercise</i><br> Fifty samples were selected from R-C3 rivers (i.e. small, mid-altitude, siliceous) in Wallonia (corresponding to the “Arden’s brooks”) showing the widest range of ecological quality from high to bad status. Each Intercalibration Common Metric (ICM) was compared (linear and polynomial regression) to IBGN scores. The highest correlation was found with the synthetic ICM index, whose high R² (0.95) allows accurate and reliable intercalibration. To IBGN EQR (i.e. Equivalent Quality Ratio) = 1 corresponds a very close ICM index value (= 1.004). Consequently, the metric IBGN score is being proposed to act as the metric for the assessment of the invertebrate fauna ecological status in Wallonia, Belgium.</p> <p align="justify"><i>Exotic and invasive species</i><br> The recent opening of the canal Danube – Main in 1992 and the subsequent navigation allowed several Ponto-Caspian macroinvertebrate species to invade successively the Rhine and the River Meuse basins. From 1998 to 2000, the monitoring network recorded four new alien species in the River Meuse in Belgium: one Polychaeta (<i>Hypania invalida</i>) and three Crustacea (<i>Hemimysis anomala, Dikerogammarus villosus, D. haemobaphes</i>). Earlier, in 1995, the Asian Bivalvia <i>Corbicula fluminea</i> and the North American Amphipod <i>Crangonyx pseudogracilis</i> were also recorded for the first time. The invasions’ dynamics were studied and discussed.</p> <p align="justify"><i>Present biological status</i> (2000-2002) of surface water-bodies in Wallonia and biological status evolution over a one-decade period (1990-2002) is included and discussed in the study. A global quality improvement of 6 % is recorded for the period. Quality improvement concerns mainly the “bad” and “poor” status raising up to “moderate” status.</p>

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Cette thèse contient deux contributions à l’homogénéisation en espace-temps des équations de Hamilton-Jacobi du premier ordre. Ces équations sont en lien avec la modélisation du trafic routier. Enfin, sont présentés des résultats d’homogénéisation en milieu presque périodique. Le premier chapitre est consacré à l’homogénéisation d’un système infini d’équations différentielles couplées avec temps de retard. Ce système provient ici d’un modèle microscopique de trafic routier simple. Les conducteurs se suivent sur une route rectiligne infinie et l’on tient compte de leur temps de réaction. On suppose que la vitesse de chaque conducteur est une fonction de l’interdistance avec le conducteur qui le précède: on parle d’un modèle du type “follow-the-leader”. Grâce à un principe de comparaison strict, on montre la convergence vers un modèle macroscopique pour des temps de réaction inférieurs à une valeur critique. Dans un second temps, on exhibe un contre-exemple à l’homogénéisation pour un temps de réaction supérieur à cette valeur critique, pour des conditions initiales particulières. Pour cela, on perturbe la solution stationnaire dans laquelle les véhicules sont tous équidistants aux instants initiaux. Le second chapitre porte sur l’homogénéisation d’une équation de Hamilton-Jacobi dont l’Hamiltonien est discontinu en espace. Le modèle de trafic associé est une route rectiligne comportant une infinité de feux tricolores. Ces feux sont supposés identiques, équidistants et le déphasage entre deux feux successifs est supposé constant. On étudie l’influence à grande échelle de ce déphasage sur le trafic. On distingue la portion de route libre, qui sera représentée par un modèle macroscopique, et les feux, qui seront modélisés par des limiteurs de flux périodiques en temps. Le cadre théorique est celui par C. Imbert et R. Monneau (2017) pour les équations de Hamilton-Jacobi sur réseaux. L’étude se décompose en l’homogénéisation théorique, où l’Hamiltonien effectif dépend du déphasage, puis l’obtention de propriétés qualitatives de cet Hamiltonien à l’aide d’observations via des simulations numériques. Le troisième chapitre présente des résultats d’homogénéisation en milieu presque périodique. On étudie tout d’abord un problème d’évolution avec un Hamiltonien stationnaire, presque périodique en espace. À l’aide d’arguments presque périodiques, on effectue dans un second temps une nouvelle preuve du résultat d’homogénéisation du second chapitre. L’Hamiltonien est alors périodique en temps et presque périodique en espace. Sont également présentes des questions encore ouvertes, notamment dans le cas où l’Hamiltonien est presque périodique en temps-espace, et dans le cas d’un modèle de trafic où les feux sont assez proches, avec donc un modèle microscopique entre les feux / This thesis report deals with the homogenization in space and time of some first order Hamilton-Jacobi equations. It contains two contributions. The corresponding equations are derived from traffic flow modelling. We finally present some results of almost periodic homogenization. In the first chapter, we consider a one dimensional pursuit law with delay which is derived from traffic flow modelling. It takes the form of an infinite system of first order coupled delayed equations. Each equation describes the motion of a driver who interacts with the preceding one: such a model is referred to as a ``follow-the-leader" model. We take into account the reaction time of drivers. We derive a macroscopic model, namely a Hamilton-Jacobi equation, by a homogenization process for reaction times that are below an explicit threshold. The key idea is to show, that below this threshold, a strict comparison principle holds for the infinite system. Above this threshold, we show that collisions can occur. In a second time, for well-chosen dynamics and higher reaction times, we show that there exist some microscopic pursuit laws that do not lead to the previous macroscopic model. Such a law is here derived as a perturbation of the stationnary solution, for which all the vehicles are equally spaced at initial times. The second chapter is dedicated to the homogenization of a Hamilton-Jacobi equation for traffic lights. We consider an infinite road where lights are equally spaced and with a constant phase shift between two lights. This model takes the form of a first order Hamilton-Jacobi equation with an Hamiltonian that is discontinuous in the space variable and the notion of viscosity solution is the one introduced by C. Imbert and R. Monneau (2017). Each light is modelled as a time-periodic flux limiter and the traffic flow between two lights corresponds to the classical LWR model. The global Hamiltonian will be time-periodic but not periodic in space for a general phase shift. We first show that the rescaled solution converges toward the solution of the expected macroscopic model where the effective Hamiltonian depends on the phase shift. In a second time, numerical simulations are used to analyse the effect of the phase shift on the effective Hamiltonian and to reveal some properties of the effective Hamiltonian from the numerical observations. In the third chapter, we are interested in some homogenization problems of Hamilton-Jacobi equations within the almost periodic setting which generalizes the usual periodic one. The first problem is the evolutionary version of the work cite {ishii2000almost}, with the same stationary Hamiltonian. The second problem has already been solved in the second chapter but we use here almost periodic arguments for the time periodic and space almost periodic Hamiltonian. We only study the ergodicity of the associated cell problems. We finally discuss open problems, the first one concerning a space and time almost periodic Hamiltonian and the second one being a microscopic model for traffic flow modelling where the Hamiltonian is almost periodic in space

A estabilidade primária, após a instalação do implante, é uma condição essencial para a aplicação de carga imediata, situação clínica cada vez mais desejada por profissionais e pacientes. O presente estudo tem como objetivo avaliar a estabilidade primária de cinco diferentes implantes instalados em bases ósseas padronizadas de osso suíno e blocos de poliuretano (modelos in vitro), por meio de ensaios biomecânicos e análise de imagens (microtomográficas e histomorfométricas). Para certificação e padronização dos cilindros de osso suíno, foram realizadas tomadas radiográficas digitais, determinando cilindros ósseos de alta e baixa densidades. Após a certificação, foram feitas microtomografias computadorizadas dos cilindros ósseos para análise tridimensional de imagens prévia à instalação dos implantes, avaliando os seguintes parâmetros: Densidade Óssea Tridimensional (BV/TV); Separação Trabecular (Tb.Sp); Porcentagem de Poros Abertos (Po.Op); Porcentagem de Poros Fechados (Po.Cl) e Porcentagem de Porosidade Total (Po.Tot). Esses parâmetros foram avaliados em quatro níveis ósseos (N1 interno às roscas do implante a ser instalado; N2 adjacente ao final das roscas até 0,5 mm destas; N3 distante 0,5 mm a 1,5 mm do final das roscas; N4 área óssea de 0 a 0,5mm da apical do implante). Depois disso, foram selecionados 50 implantes de 5 diferentes modelos, divididos em 5 grupos com 10 implantes cada: Grupo 1 (G1): implantes Xive Plus inseridos em cilindros ósseos de alta (n=5) e de baixa densidades (n=5); Grupo 2 (G2): implantes Ankylos inseridos em cilindros ósseos de alta (n=5) e de baixa densidades (n=5); Grupo 3 (G3): implantes Bone Level inseridos em cilindros ósseos de alta (n=5) e de baixa densidades (n=5); Grupo 4 (G4): implantes AlvimCM inseridos em cilindros ósseos de alta (n=5) e de baixa densidades (n=5); Grupo 5 (G5): implantes DriveCM inseridos em cilindros ósseos de alta (n=5) e de baixa densidades (n=5). A instalação de todos implantes seguiu o protocolo recomendado pelos fabricantes, sendo realizada a medida do torque de inserção (IT) e logo após a análise de Coeficiente de Estabilidade do Implante - ISQ (avaliação por Frequência de ressonância - RFA). Após a instalação dos implantes nos cilindros ósseos, estes foram submetidos a nova análise tridimensional com os mesmos parâmetros e níveis ósseos. Para as análises nos blocos de poliuretano, foram seccionados 50 blocos de alta e baixa densidade (D1 e D3, respectivamente), e inseridos 50 implantes individualmente nos blocos, utilizando 10 de cada e divididos em 5 grupos: Grupo 6 (G6): implantes Xive Plus inseridos em blocos de poliuretano de alta densidade - D1 (n=5) e de baixa densidade - D3 (n=5); Grupo 7 (G7): implantes Ankylos inseridos em blocos de poliuretano de alta densidade - D1 (n=5) e de baixa densidade - D3 (n=5); Grupo 8 (G8): implantes Bone Level inseridos em blocos de poliuretano de alta densidade - D1 (n=5) e de baixa densidade - D3 (n=5); Grupo 9 (G9): implantes AlvimCM inseridos em blocos de poliuretano de alta densidade - D1 (n=5) e de baixa densidade - D3 (n=5); Grupo 9 (G9): implantes DriveCM inseridos em blocos de poliuretano de alta densidade - D1 (n=5) e de baixa densidade - D3 (n=5). Após a inserção dos implantes, estes também foram analisados com relação ao torque de inserção, frequência de ressonância e através do ensaio de arrancamento. Os ensaios biomecânicos mostraram que os implantes instalados no G4 (AlvimCM) e G5 (DriveCM) tiveram maior valores de IT e de RFA em ambas as bases ósseas suínas. Nos blocos de poliuretano, tiveram resultados semelhantes entre as bases ósseas para quase todos os implantes nos testes IT e RFA, havendo um maior valor no ensaio de arrancamento para os implantes Bone Level (G8). Os resultados para todas os parâmetros avaliados por MicroCT mostraram que as diferenças dos valores pós e pré-inserção dos implantes revelaram significância estatística principalmente para G4 e G5 em relação aos outros grupos. A análise histomorfométrica mostrou maiores valores de compactação óssea e de Contato Osso-Implante (BIC) para G2, G4 e G5. Para todas as análises de imagem foi observada uma tendência de maior compactação nos N1, N2 e N4; no N3 não houve um aumento significativo da condensação óssea pós-inserção do implante. Concluiu-se que os implantes AlvimCM e DriveCM mostraram melhores resultados nos testes biomecânicos e em relação ao aumento da densidade óssea ao redor do implante, avaliada pelos métodos de imagem, e que estes resultados estiveram correlacionados à estabilidade primária exibida pós-inserção. Os resultados histomorfométricos confirmaram os resultados obtidos pela análise microtomográfica, demonstrando assim a validade do método 3D de análise por imagem. / The primary stability, after implant installation, is an essential condition for the application of immediate loading, clinical situation increasingly desired by professionals and patients. The present study has the objective of evaluating the primary stability of five different implants installed in standard bone bases of swine bone and polyurethane blocks (in vitro models), through biomechanical tests and image analysis (microtomographic and histomorphometric). For the certification and standardization of the swine bone cylinders, digital radiographs were taken, determining bone cylinders of high and low density. After the certification, computerized microtomographies of the bone cylinders were performed for three-dimensional analysis of images prior to implant installation, evaluating the following parameters: Three-dimensional Bone Density (BV / TV); Trabecular Separation (Tb.Sp); Percent of Open Pore (Po.Op); Percent of Closed Pores (Po.Cl) and Percentage of Total Porosity (Po.Tot). These parameters were evaluated in four bone levels (N1 - internal to the threads of the implant to be installed, N2 - adjacent to the end of the threads up to 0.5 mm of these, N3 - distant 0.5 mm to 1.5 mm from the end of the threads ; N4 - bone area 0 to 0.5 mm from the apical of the implant). After that, 50 implants of 5 different models were divided into 5 groups with 10 implants each: Group 1 (G1): Xive Plus implants inserted into high (n = 5) and low density (n = 5) ; Group 2 (G2): Ankylos implants inserted into high (n = 5) and low density (n = 5) bone cylinders; Group 3 (G3): Bone Level implants inserted into bone cylinders of high (n = 5) and low density (n = 5); Group 4 (G4): AlvimCM implants inserted into high (n = 5) and low density (n = 5) bone cylinders; Group 5 (G5): DriveCM implants inserted into high (n = 5) and low density (n = 5) bone cylinders. The implantation of all implants followed the protocol recommended by the manufacturers, and the measurement of the insertion torque (IT) and soon after the analysis of Implantation Stability Coefficient (ISQ (evaluation by Frequency of Resonance - RFA)). After the implants were installed in the bone cylinders, they were submitted to a new three-dimensional analysis with the same parameters and bone levels. 50 blocks of high and low density (D1 and D3, respectively), and 50 implants were inserted individually into the blocks, using 10 of each and divided into 5 groups: Group 6 (G6): implants Xive Plus inserted in blocks of high density polyurethane - D1 (n = 5) and low density - D3 (n = 5); Group 7 (G7): Ankylos implants inserted in blocks of high density polyurethane - D1 (n = 5) and low density - D3 (n = 5); Group 8 (G8): Bone Level implants inserted in blocks of high density polyurethane - D1 (n = 5) and low density - D3 (n = 5); Group 9 (G9): AlvimCM implants inserted in blocks of high density polyurethane - D1 (n = 5) and low density - D3 (n = 5); Group 9 (G9): DriveCM implants inserted in blocks of high density polyurethane - D1 (n = 5) and low density - D3 (n = 5). After insertion of the implants, these were also analyzed with respect to the insertion torque, resonance frequency and through the pullout test. The biomechanical tests showed that the implants installed in G4 (AlvimCM) and G5 (DriveCM) had higher IT and RFA values in both porcine bone bases. In the polyurethane blocks, similar results were found between the bone bases for almost all implants in the IT and RFA tests, with a higher value in the pullout test for Bone Level (G8) implants. The results for all the parameters evaluated by MicroCT showed that the differences in the post-insertion and pre-insertion values of the implants revealed statistical significance mainly for G4 and G5 in relation to the other groups. The histomorphometric analysis showed higher Bone Compaction and Bone Implant (BIC) compaction values for G2, G4 and G5. For all the image analyzes a tendency of greater compaction was observed in N1, N2 and N4; in N3 there was no significant increase in bone post-insertion implant condensation. It was concluded that the AlvimCM and DriveCM implants showed better results in the biomechanical tests and in relation to the increase of the bone density around the implant, evaluated by the imaging methods, and that these results were correlated to the primary stability exhibited post-insertion. The histomorphometric results confirmed the results obtained by the microtomographic analysis, thus demonstrating the validity of the 3D image analysis method.

O presente trabalho visa empregar uma metodologia numérica para determinar as propriedades macro mecânica de compósitos ativos (AFC - Active Fiber Composite ou MFC - Macro Fiber Composite), combinando o conceito de Volume Elementar Representativo (VER) com o Método dos Elementos Finitos (MEF). Inicialmente, apresenta-se a fundamentação teórica associada à abordagem numérica empregada. Posteriormente, os modelos numéricos desenvolvidos são aplicados na determinação dos coeficientes efetivos de materiais compósitos inteligentes transversalmente isotrópicos com fibras piezelétricas de seção com forma circular e quadrada, respectivamente. Finalmente, os resultados numéricos obtidos pela metodologia proposta são, então, comparados com resultados da literatura. Constata-se que os resultados obtidos são muito semelhantes aos resultados relatados pela literatura para arranjo quadrático e hexagonal com fibra de geometria circular, sendo que neste caso, compararam-se os resultados numéricos com analíticos obtidos através do Método de Homogeneização Assintótica. Em seguida, a metodologia é aplicada para determinação dos coeficientes efetivos para arranjo quadrático e hexagonal com fibra de geometria quadrada. Empregando diferentes frações volumétricas de fibras, os resultados via MEF foram comparados aos resultados analíticos obtidos através do Método dos Campos Uniformes (Uniform Field Method). Após a avaliação das limitações e potencialidades da metodologia, de forma direta, através de resultados analíticos, realizou-se a avaliação da mesma de forma indireta. Para tal, foram realizadas análises dinâmicas visando comparar as Funções de Resposta em Frequência (FRF) experimentais com as obtidas computacionalmente. Dessa forma, utilizou-se uma viga de alumínio estrutural engastada-livre, onde foram colados duas pastilhas piezelétricas, sendo uma para realizar a excitação da estrutura e, a outra para fazer a aquisição dos dados. Os modelos computacionais via MEF empregaram para o domínio das pastilhas, as propriedades efetivas determinadas através da metodologia desenvolvida. Os resultados obtidos demonstraram mais uma vez as potencialidades da metodologia proposta. Assim, conclui-se que a metodologia numérica não é somente uma boa alternativa para o cálculo de coeficientes efetivos de compósitos inteligentes, mas também uma ferramenta para o projeto de estruturas inteligentes monitoradas por materiais piezelétricos. / This work presents the development a numerical methodology to determine the mechanical properties of active macro composites (AFC - Active Fiber Composite, or MFC - Macro Fiber Composite), combining the concept of Representative Elementary Volume (REV) with the Finite Element Method (FEM). In the first instance, the theoretical framework associated with the numerical approach employed is presented. Later, numerical models based on unit cell are applied to predict the effective material coefficients of the transversely isotropic piezoelectric composite with circular cross section fibers. Finally, numerical results obtained by the proposed methodology are compared to other methods reported in the literature. It appears that the results are very similar to the literature results for square and hexagonal arrangement of fibers with circular geometry, in which case, it was compared numerical with analytical results calculated by Asymptotic Homogenization Method (AHM). After that, the methodology is applied to determine the effective coefficients for square and hexagonal array with square fiber geometry. Employing different fiber volume fractions, it follows that the results obtained by the proposed methodology were compared to analytical results calculated by the Uniform Field Method (UFM). After assessing the potential and limitations of the methodology, either directly, through analytical results, the evaluation took place in the indirect approach. Then, dynamic analyses were performed in order to compare the Frequency Response Functions (FRFs) determined by experimental tests with computational results. Thus, it was used a cantilever beam aluminum structure, which were bonded two piezoelectric patches, one to carry the excitement of the structure and the second to perform the data acquisition. The effective properties determined by the proposed methodology were applied for the dominium established by the piezoelectric patches. The results showed, again, the potential of the proposed methodology. Therefore, the numerical methodology is not only a good alternative for the calculation of effective coefficients of smart composite, but also a tool for the design of smart structures monitored by piezoelectric materials.