La signalisation cellulaire induite par les r écepteurs à sept domaines transmembranaires (R7TM) contrôle les principales fonctions physiologiques humaines. Ces R7TMs sont cibles de m édicaments et initient de larges réseaux d'interactions. Nous avons modélisé dynamiquement les réseaux de signalisation du récepteur à l'hormone folliculo-stimulante (FSH) régulant la fonction de reproduction et du récepteur angiotensine, un R7TM modèle régulant la tension pour comprendre le fonctionnement de ces réseaux et prédire des données inaccessibles expérimentalement. Notre modélisation a utilisé des équations différentielles ordinaires, en assimilant une variable par espèce et un paramètre par constante cinétique. Les paramètres manquant ont été déterminés par optimisation paramétrique. Puis, nous avons d éveloppé un environnement afin de comparer plusieurs algorithmes d'optimisation et de créer une nouvelle méthode hybride plus performante et adaptée à la paramétrisation des réseaux de signalisation.

Ce projet de recherche s’inscrit dans un partenariat entre l’ANDRA (Agence Nationale pour la gestion des Déchets Radioactifs) et le LOSI de l’Institut Charles Delaunay (STMR UMR CNRS), UTT.La thèse vise à dimensionner les ouvrages de stockage vis-à-vis des divers flux industriels. Les flux concernés sont de nature variée et cela constitue l’une des caractéristiques du stockage. Les ouvrages doivent en effet être conçus pour permettre un développement progressif, à l’origine d’une coexistence de flux nucléaires (les colis de déchets nucléaires et les flux associés, telle la ventilation nucléaire) et de flux de chantiers conventionnels. Le dimensionnement des flux et la conception des ouvrages pour autoriser ces flux se trouvent donc au cœur du processus de conception du stockage.La problématique de notre partenaire industriel porte sur la conception de réseau (appelé flow path design). Notre contribution est dédiée au développement de modèles de flow path design avec de nouvelles contraintes ainsi qu’au développement de méthodes. Les extensions au modèle de base prennent en compte une flotte hétérogène, des segments interdits d’accès à certains véhicules et des coûts de construction. Différentes méthodes d'optimisation approchées ont aussi été développées et testées. Il s’agit de métaheuristiques basées sur les recherches locales, l’algorithme de colonies de fourmis ainsi que l’algorithme des abeilles. L’efficacité des méthodes est prouvée grâce à des tests sur des instances de la littérature et l’application au cas réel est faite par simulation / This research project is part of a partnership between ANDRA (National Agency for Radioactive Waste Management) and the LOSI, Institut Charles Delaunay (TSR UMR CNRS), UTT.The thesis aims to design the storage structures for various industrial flows. Flows involved are varied in nature and it is one of the characteristics of the storage. The works must be designed to effect a gradual development, from a "coactivity", that is to say, a coexistence of nuclear flux (the nuclear waste packages and the associated flow, such nuclear ventilation) and conventional flow sites. The design flow and the design of structures to allow these flows are therefore at the heart of the design process of storage.The problem of our industrial partner focuses on flow path design. Our contribution is dedicated to the development of models of flow path design with new constraints and the development of methods. Extensions to the basic model takes into account different type of vehicle, not allowed some segments and taking into account construction costs. Different optimization methods have also been developed and tested. Metaheuristics are based on local search, the ant colony algorithm and the algorithm of bees. Efficiency of methods is demonstrated through tests on literature benchmarks and application to the real case is done by simulation

Doctorat en sciences sociales, politiques et économiques / info:eu-repo/semantics/nonPublished

Détection précoce de crises<p>d’épilepsie à l’aide d’une<p>modélisation du comportement<p>oscillatoire neuronal / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished

This thesis focuses on a central behavioral paradox in the asset management community. Recent decades have brought an upsurge in initiatives throughout the investment community to voluntarily integrate sustainability issues into investment decisions. The financial crisis has however revealed behavioral inconsistency and deepening irresponsibility. Today, sustainable investments represent USD 10.7 trillion, or 7% of the entire market, of assets under management and it is growing steadily. <p>One important driver of this growth was the emergence of specialized research agencies that standardized measurement of companies’ environment, social, and governance (ESG) performance and sold such information as a tool to evaluate or pressure corporate conducts. More recently, sell-side research, financial news, and market-index providers joined the ESG information market, where they aim to support more mainstream asset managers in integrating ESG information into investment decisions. <p>A dominant assumption has taken hold in a large part of the investment and regulatory circles: asset managers’ use of ESG information will induce a behavioral change so that they automatically integrate companies’ sustainability to investment return concerns. Understandings of what constitutes sustainable investment have been largely practitioner-driven. The academic community took little interest to challenge the assumption. Remarkably, more scholars have come to assume that conformance to institutional pressures to add ESG information to investment strategies will induce more sustainable and long-term behavior of investors and companies. ESG information integration is believed to be a behavioral enabler for mainstream investors to systematically embed sustainability in investment strategies. Because of the assumption, theory building of asset manager intrinsic motivations to engage in sustainable investment remains unexplored. Main contribution of this research is to generate a deep theoretical understanding of asset manager non-conformance to the ESG pressure to engage in sustainable investment. <p>The research starts by questioning the dominant assumptions made in the sustainable investment field. While working in the industry, I witnessed some asset managers’ practices of replacing the externally defined ESG information with their own research based on narratives to better understand investee companies. The research question came out of this experience: why do some asset managers use ESG information to engage in sustainable investment while others do not? Do pressures to integrate ESG information really induce more sustainable behaviors on the part of asset managers? These self-inquiries led to a wide array of literature review to search for conformance and non-conformance drivers. Surprisingly, non-conformance was an under-researched theme. Given the scarcity of the research, I sought a method that would enable grounded theorizing based on asset managers’ own experience and interpretations. <p> Grounded theory research draws on asset manager interviews, archival documents, expert and practitioner consultations and feedback during 2007 and mid-2011. To reflect the global nature of sustainability, I focused on global equity asset managers working in thirteen institutions in three lead markets with most geographically diversified sustainable investment, UK, the Netherlands and Belgium. <p>Theory building from the ground up does not happen in vacuum. I developed a framework to study conformance and non-conformance drivers to facilitate the concept elicitation. The question of conformance and non-conformance has been studied by institutional, resource-based view of the firm, behavioral finance, cognitive and sensemaking theorists but in a disintegrated manner. I enhanced insights by way of aggregating and exploring the drivers. The framework illuminates the viability of both conformers and non-conformers in sustainable investment practices. Both are leadership activities of asset managers based respectively on explicit and implicit motivations. It illustrates short-term and opportunistic motivations of conforming managers, as opposed to long-term and substantial motivations of non-conforming managers to integrate sustainability and return-making in their investment decisions. <p>The research results presented hereafter provide a significant theoretical and empirical contribution. Drawing from insights and perspectives from the practitioners, a grounded theory model of asset manager conformance and non-conformance highlights a pivotal concept of sensemaking capacities. It reveals a counter intuitive pattern of asset manager learning. Non-conforming asset managers have developed a distinctive capacity to integrate sustainability and investment return concerns regardless of public pressures to do so. This distinctive sensemaking capacity, founded on behavioral integration of external expectations with own motivation, goal, competence and know-how, was the strategic resource for the organization. Their behavioral integration of sustainability and return generation is so highly developed, that adding the ESG information in their investment strategy would actually impair their capacity to make sense of sustainability. Indeed, I find that non-conforming asset manager teams have sustained consistent returns and increased client assets throughout the financial crisis. In absence of such behavioral integration and sensemaking capacities, conforming managers failed to sustain consistency or suffered from under-funding. To stay competitive, the latter managers have fervently demonstrated the ESG information use in their investment strategies. However, such explicit demonstration of leadership has not been accompanied by distinctive sensemaking capacities. I find that conforming managers were less capable of integrating sustainability and return-generation, which subsequently reinforced their short-termism and opportunism. <p>The finding of this thesis points to the importance of ‘behavioral integration’ instead of ‘explicit conformance’ of asset managers. The academic community may need to shed a more critical eye on ESG integration by asset managers. Institutional pressures to adopt such information may not induce more sustainable behavior, as ESG know-how is likely to deprive a chance to develop distinctive sensemaking capacities. Furthermore, it may even hurt the sensemaking capacities of managers who have behaviorally integrated sustainability and return-generation. While I hope to trigger a re-think amongst academics how to promote sustainable investment, my findings has theoretical and empirical contributions. The most important theoretical contribution is identification of non-conformance variables to engage intrinsically in sustainable investment. Empirical evidence on non-conformers, corroborated with resource-based view of the firm, also enhances the understanding of non-conformers’ motivation to sustain competitive advantage. <p>Findings also lead to managerial and policy implications. I carried out this research in the midst of the financial crisis, a time of mounting European policy debates how to build investor capacity to induce long-term and sustainable behaviors. The European Commission’s Internal Market Directorate-General is set to publish a directive proposal that mandate ESG information disclosure to companies and ESG reporting by investors. This adds weight to already published procedural measures to strengthen corporate governance at financial institutions. These policy initiatives emerged largely because of expert consultation and anecdotal evidences. In addition to recommendations to specific pieces of legislative proposals, this research makes an overarching policy proposal. The EU Commission needs to reexamine if the current policy measures lead to further symbolic demonstrations of ESG usage without accompanying sustainable behavior at the cost of real economy. EU equally needs to pay more attention to non-conforming asset managers’ distinctive capacities and enabling mechanisms. Reporting burdens may inadvertently impair non-conforming managers’ capacities to sustain long-term performance and may induce a contradictory policy consequence of increased public distrust. <p> / Doctorat en Sciences économiques et de gestion / info:eu-repo/semantics/nonPublished

In this global world, many firms present a complex shareholding structure with<p>indirect participation, such that it may become difficult to assess a firm’s controllers.<p>Furthermore, if there are numerous dominant shareholders, the control can be shared between<p>them. Determining who has the most influence is often a difficult task. To measure this<p>influence, game theory allows the modeling of voting games and the computing of the<p>Banzhaf index. This thesis develops models to measure the Banzhaf indices in any ownership structure (pyramidal ownership structures and cross-ownership structures). The models are then applied to real cases studies such Colruyt, Elia, Lafarge and Allianz. / Doctorat en Sciences économiques et de gestion / info:eu-repo/semantics/nonPublished

Can we fruitfully use the same macroeconomic model to forecast and to perform policy analysis? There is a tension between a model’s ability to forecast accurately and its ability to tell a theoretically consistent story. The aim of this dissertation is to propose ways to soothe this tension, combining structural and reduced-form models in order to have models that can effectively do both. / Doctorat en Sciences économiques et de gestion / info:eu-repo/semantics/nonPublished

The segmentation problem arises in the elaboration of a radiation therapy plan. After the cancer has been diagnosed and the radiation therapy sessions have been prescribed, the physician has to locate the tumor as well as the organs situated in the radiation field, called the organs at risk. The physician also has to determine the different dosage he wants to deliver in each of them and has to define a lower bound on the dosage for the tumor (which represents the minimum amount of radiation that is needed to have a sufficient control of the tumor) and an upper bound for each organ at risk (which represents the maximum amount of radiation that an organ can receive without damaging). Designing a radiation therapy plan that respects these different bounds of dosage is a complex optimization problem that is usually tackled in three steps. The segmentation problem is one of them.<p><p>Mathematically, the segmentation problem amounts to decomposing a given nonnegative integer matrix A into a nonnegative integer linear combination of some binary matrices. These matrices have to respect the consecutive ones property. In clinical applications several constraints may arise that reduce the set of binary matrices which respect the consecutive ones property that we can use. We study some of them, as the interleaf distance constraint, the interleaf motion constraint, the tongue-and-groove constraint and the minimum separation constraint.<p><p>We consider here different versions of the segmentation problem with different objective functions. Hence we deal with the beam-on time problem in order to minimize the total time during which the patient is irradiated. We study this problem under the interleaf distance and the interleaf motion constraints. We consider as well this last problem under the tongue-and-groove constraint in the binary case. We also take into account the cardinality and the lex-min problem. Finally, we present some results for the approximation problem. <p><p>/Le problème de segmentation intervient lors de l'élaboration d'un plan de radiothérapie. Après que le médecin ait localisé la tumeur ainsi que les organes se situant à proximité de celle-ci, il doit aussi déterminer les différents dosages qui devront être délivrés. Il détermine alors une borne inférieure sur le dosage que doit recevoir la tumeur afin d'en avoir un contrôle satisfaisant, et des bornes supérieures sur les dosages des différents organes situés dans le champ. Afin de respecter au mieux ces bornes, le plan de radiothérapie doit être préparé de manière minutieuse. Nous nous intéressons à l'une des étapes à réaliser lors de la détermination de ce plan: l'étape de segmentation.<p><p>Mathématiquement, cette étape consiste à décomposer une matrice entière et positive donnée en une combinaison positive entière linéaire de certaines matrices binaires. Ces matrices binaires doivent satisfaire la contrainte des uns consécutifs (cette contrainte impose que les uns de ces matrices soient regroupés en un seul bloc sur chaque ligne). Dans les applications cliniques, certaines contraintes supplémentaires peuvent restreindre l'ensemble des matrices binaires ayant les uns consécutifs (matrices 1C) que l'on peut utiliser. Nous en avons étudié certaines d'entre elles comme celle de la contrainte de chariots, la contrainte d'interdiciton de chevauchements, la contrainte tongue-and-groove et la contrainte de séparation minimum.<p><p>Le premier problème auquel nous nous intéressons est de trouver une décomposition de la matrice donnée qui minimise la somme des coefficients des matrices binaires. Nous avons développé des algorithmes polynomiaux qui résolvent ce problème sous la contrainte de chariots et/ou la contrainte d'interdiction de chevauchements. De plus, nous avons pu déterminer que, si la matrice donnée est une matrice binaire, on peut trouver en temps polynomial une telle décomposition sous la contrainte tongue-and-groove.<p><p>Afin de diminuer le temps de la séance de radiothérapie, il peut être désirable de minimiser le nombre de matrices 1C utilisées dans la décomposition (en ayant pris soin de préalablement minimiser la somme des coefficients ou non). Nous faisons une étude de ce problème dans différents cas particuliers (la matrice donnée n'est constituée que d'une colonne, ou d'une ligne, ou la plus grande entrée de celle-ci est bornée par une constante). Nous présentons de nouvelles bornes inférieures sur le nombre de matrices 1C ainsi que de nouvelles heuristiques.<p><p>Finalement, nous terminons par étudier le cas où l'ensemble des matrices 1C ne nous permet pas de décomposer exactement la matrice donnée. Le but est alors de touver une matrice décomposable qui soit aussi proche que possible de la matrice donnée. Après avoir examiné certains cas polynomiaux nous prouvons que le cas général est difficile à approximer avec une erreur additive de O(mn) où m et n représentent les dimensions de la matrice donnée. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Doctorat en sciences sociales, politiques et économiques / info:eu-repo/semantics/nonPublished

L’objectif général de cette thèse est de montrer qu’il est possible de révéler l’idéologie qui caractérise un discours, en se fondant sur son étude sémantique et en s’attachant à la description détaillée des mots de la langue. Dans cette perspective, nous nous sommes intéressée au discours des théoriciens de l’Antiquité Grecque lorsqu’ils ont décrit le phénomène musical. Les premiers témoignages concernant les rapports entre la musique et les mathématiques proviennent des écrits pythagoriciens. Les auteurs de la Grèce Classique de nous les plus connus, Platon, Aristote et son disciple Aristoxène en particulier, s’exprimèrent bien souvent au sujet de la musique en tenant compte de ce qu’ils savaient des théories pythagoriciennes à ce sujet, que ce soit pour les suivre, les développer ou au contraire, les critiquer. Quel que soit leur point de vue, ils constituent pour nous la source permettant de reconstruire les théories pythagoriciennes. L’engouement pour la théorie et ses structures abstraites, inspirées de l’essor des premières mathématiques constitue une caractéristique des discours sur la musique que nous étudions. Pour angle d’approche, notre travail pluridisciplinaire s’est efforcé de contribuer à une meilleure connaissance du rôle des opposés ὀξύς [oxus] et βάρυς [barus] dans la construction d’un savoir proprement musical comme dans les premières pierres d’un savoir scientifique et philosophique dans l’Antiquité grecque. Pour mieux comprendre le rôle de ces mots, nous utilisons, sur la langue grecque ancienne, le modèle de description sémantique proposée par la Sémantique des Points de Vue, sémantique dont l’objectif est de mettre au jour l’idéologie cristallisée dans les mots de la langue. / The general objective of this thesis is to show that the ideology characterizing a discourse can be revealed by its semantic study and, more precisely by the detailed description of the words of the language in which this discourse is uttered. With this objective in mind, we have worked on the texts of the Greek Antiquity theoreticians in which they describe the musical phenomenon. The first testimonies about the relationship between music and mathematics can be found in the Pythagorean texts. When the best-known authors Plato, Aristotle and more particularly his disciple Aristoxenus wrote about music, they drew their inspiration from what they knew of the Pythagorean theories, either to follow and develop them or, on the contrary, to criticize them. Whatever their position on the matter, they form the source from which the Pythagorean theories can be reconstructed. The craze for theory and abstract structures, inspired by the development of the first mathematics constitutes a striking feature of the discourses on music we study. We have chosen to envisage the corpus with a multidisciplinary approach to further comprehend the role of the opposites oxus and barus in the building of the musical knowledge, as well as in the construction of the scientific and philosophic knowledge in ancient Greece. In order to better understand the role of these words, we use the Viewpoints Semantics, whose main goal is to systematically reveal the ideology crystallized in the words of natural languages.