La recherche de moyens alternatifs pour la propulsion d'un aéronef est primordiale tant la dépendance au pétrole est forte. Le travail proposé dans cette thèse s'inscrit dans le besoin de soutenir les concepteurs de systèmes de propulsion innovants utilisant l'électricité. En partant du constat qu'il est primordial de s'appuyer sur l'analyse de l'aéronef dans sa globalité, nous proposons une approche basée sur les modèles, faisant appel aux modèles d’ingénierie système, aux modèles comportementaux basés sur la physique et à la simulation numérique, et collaborative, car la conception implique de nombreux métiers.L'objectif de cette approche est la création d'un produit virtuel qui est un modèle global multidisciplinaire exécutable du produit pour en faciliter la conception. Une méthodologie est alors construite pour se concentrer sur la relation entre le produit virtuel, ses modèles constitutifs et leur obtention. Le fil directeur de la méthodologie correspond à une recherche d'informations, au moyen de l'analyse des interactions et impacts multidisciplinaires qui apparaissent dans le système, puis l'application de cette information pour la construction d'un modèle d'intention qui permet la requête de modèles comportementaux auprès d'experts. C'est finalement le lien manquant entre la conception globale conduite par l'ingénierie système et la conception basée sur la physique du monde réel qui est implicitement traité dans ces travaux. Pour réaliser l'ensemble de la méthodologie, un nouveau rôle a été défini, le rôle d'architecte de simulation. Cette thèse présente la méthodologie de manière théorique, incluant ses rôles et concepts, puis cette dernière est démontrée sur un cas d'étude correspondant à l'hybridation d'un drone de type hélicoptère. / The research of alternative aircraft propulsion system is mandatory because oil dependence is too strong. The work proposed in this thesis is oriented to support electric based innovative propulsion system designers. Considering that it is important to consider entire aircraft analysis, we propose a model based, with systems engineering models, physics-based behavioral models and numerical simulation, and collaborative, because design require numerous business expertise. The objective of this approach is to build a virtual product, which means a global multidisciplinary executable model of the product under design in order to facilitate its design. A methodology is then developed, focused on the relation between the virtual product, its constitutive models and their acquisition. The methodology director wire corresponds to information research, with multidisciplinary interactions and impacts in the system, and then the application of those pieces of information to build a model of intention which allows requesting a behavioral model from experts. Finally, it is the missing link between global design driven with systems engineering and real physics based design which is implicitly at stake. To perform the methodology, a new role has been defined, the simulation architect. This thesis presents theoretically the methodology, including roles and concepts, and then this methodology is demonstrated on a helicopter based drone study-case.

Cette thèse vise à mieux comprendre de quelle manière les ateliers scientifiques animés par des chercheurs à l’université essayent de motiver les élèves de l’école primaire au lycée à suivre une carrière scientifique universitaire. Notre défi majeur a été d’analyser ces ateliers scientifiques à une fin didactique en prenant en compte la complexité d’interactions des acteurs et leurs attentes. Ainsi, ce travail repose sur une analyse des ateliers en les considérant comme un système dynamique complexe. Nous articulons une approche qualitative qui consiste en un « noyau d’analyse complexe » d’une triangulation systémique entre le contexte, la stratégie et la production.Dans cette perspective, cette thèse apporte une réflexion sur la culture des évaluations dans le domaine de l'éducation en proposant une modélisation d’une « évaluation multiréférentielle » basée sur trois critères : l’efficacité, la pertinence et l’efficience. Pour ce faire, différents niveaux d’analyse sont proposés à partir de questionnaires et d’entretiens auprès d’élèves, de médiateurs et d’enseignants, ayant participé à des ateliers.Les résultats ont mis en évidence des décalages entre les objectifs des acteurs et les visées institutionnelles affichées pour ces ateliers. L’enjeu pour les médiateurs, les enseignants et les élèves se situe avant tout dans un registre du plaisir. En plus, les médiateurs interrogés valorisent peu leur parcours scolaire et universitaire, alors que les élèves voient avant tout le parcours du chercheur comme relevant d’une vocation. / This thesis aims to better understand how scientific workshops led by researchers at the university try to motivate students from primary school to high school to pursue a university science career. Our major challenge was to analyse the scientific workshops with a didactical goal by taking into account the complexity of interactions between its actors and their expectations. As such, this work is based on a analysis of the workshops, as these are seen as a complex dynamic system. We articulate a qualitative approach consisting in a “complex core of analysis” and a systemic triangulation of the system: the context, the strategies and the production.In this perspective, this thesis reflets on the culture of assessment in education by proposing a modelisation of a “multireferencial assessment” based on three criteria: the efficacy, the relevance and the efficiency. To do that, different levels of analyses are proposed based on questionnaires and interviews of students, mediators and teachers who were engaged in workshopsThe results have especially highlighted the gap between the objectives of the workshops' participants and a those of the institutional presented for these workshops. For the mediators, the teachers and the students, these workshops are primarily meant to enjoy the activities. More, mediators who took part in the study express little interest in showing a positive view of their own academic background and their career, whereas students see, before anything else, researchers’ career as a vocation.

L’évolution du Web et de ses applications subit depuis quelques années une mutation vers les technologies qui incluent la dimension sociale comme entité de première classe. Nous témoignons dans le passage du Web 1.0 au Web 2.0 puis au Web 3.0, 4.0 etc.. que les utilisateurs et les réseaux sociaux qui se forment sont au centre de cette évolution. Le web exhibe aussi toutes les caractéristiques d’un système complexe. Ces propriétés systèmes complexes et cette dimension sociale doivent être prises en considération lors de la conception et le développement des applications web. Considérons le cas des systèmes de tagging ou d’étiquetage collaboratifs. Ces systèmes sont un exemple de systèmes complexes, auto-organisés et socialement conscients. Le paradigme des systèmes multi-agents coordonné par les mécanismes d’auto-organisations a été utilisé d’une façon effective pour la conception et modélisation des systèmes complexes. Les systèmes de tagging collaboratifs actuels ne prennent pas l’avantage complet de leurs caractéristiques systèmes complexes, surtout dans l’adaptation à leur environnement et l’émergence de nouvelles fonctionnalités. Dans ce travail de thèse, nous proposons un modèle pour la conception et développement d’un nouveau système d’étiquetage collaboratif MySURF (My Similar Users, Resources, Folksonomies), utilisant une approche multi-agents gouvernée par la coévolution des organisations sociales et spatiales des agents. Nous montrons comment ce système proposé offre plusieurs nouvelles fonctionnalités qui peuvent améliorer les systèmes d’étiquetage collaboratifs actuels. / The evolution of the Web and its applications has undergone in the last few years a mutation towards technologies that include the social dimension as a first class entity. We are witnessing in the evolution of the web from the web 1.0 to web 2.0 to web 3.0 and eventually web 4.0 that the users, their interactions and the emerging social networks are in the center of this evolution. The web also exhibits all the characteristics of a complex system. These complex systems properties and this social dimension must be taken into consideration in the design and the development of new web applications. Let us consider the case of collaborative tagging systems. These systems are an example of complex, self-organized and socially aware systems. The multi-agent systems paradigm coordinated by self-organizations mechanisms was used in an effective way for the design and modeling of the complex systems. Current collaborative tagging systems do not take full advantage of the characteristics of complex systems, especially in adapting to their environment and the emergence of new features. In this thesis, we propose a model for the design and development of a new collaborative tagging system MySURF (My Similar Users, Resources, Folksonomies), using a multi-agent system approach governed by the coevolution of the social and spatial organization of the agents. We show how the proposed system offers several new features that can improve current collaborative tagging systems.

Developments in electric technologies have the potential to increase the efficiency and performance of commercial aircraft. However, without proper architecture innovation, technology developments at the subsystem level are not sufficient to ensure successful integration. Adaptations to existing architectures work well when trades are made strictly between equivalent systems which fulfill and induce the same functional requirements. However, this approach does not provide the architect with adequate flexibility to integrate technologies with differing functional and physical interfaces. Architecture redefinition is required for proper implementation of non-traditional and innovative architectural elements. A function-based process for innovative architecture design was developed to provide flexibility in the definition of candidate architectural concepts. Tools and methods were developed which facilitate the definition and exploration of a function-based architectural design space. These include functional decomposition, functional induction, dynamic morphology, adaptive functional mapping, reconfigurable mission definition, and concept level system installation. The Architecture Design Environment (ADEN) was built to integrate these tools and to facilitate the definition of physics-based models in evaluating the performance of candidate architectures. Using functions as the foundation of this process assists in mitigating assumptions which traditionally govern architecture structures and offers a promising approach to architecting through flexible conceptualization and integration. This toolset provides the framework wherein knowledge from conceptual, preliminary, and detailed design efforts can be linked in the definition of revolutionary architectures.

This paper presents the cooperative modelling methodology used in the Information Society foresight carried out within the research project SCETIST. The class of models here presented used the concept of group decision creativity that has been elaborated for the use in a Living Lab. The trends and scenarios are discussed and refined during cooperative activities, finally verified using the simulation of a hybrid system consisting of qualitative information processing, and a discretetime- control system with a discrete-event component.

This thesis examines the utility of mathematical complexity measures for the analysis of stratospheric dynamics. Through theoretical considerations and tests with artificial data sets, e.g., the iteration of the logistic map, suitable parameters are determined for the application of the statistical entropy measures sample entropy (SE) and Rényi entropy (RE) to methane (a long-lived stratospheric tracer) data from simulations of the SOCOL chemistry-climate model. The SE is shown to be useful for quantifying the variability of recurring patterns in a time series and is able to identify tropical patterns similar to those reported by previous studies of the ``tropical pipe'' region. However, the SE is found to be unsuitable for use in polar regions, due to the non-stationarity of the methane data at extra-tropical latitudes. It is concluded that the SE cannot be used to analyse climate complexity on a global scale. The focus is turned to the RE, which is a complexity measure of probability distribution functions (PDFs). Using the second order RE and a normalisation factor, zonal PDFs of ten consecutive days of methane data are created with a Bayesian optimal binning technique. From these, the RE is calculated for every day (moving 10-day window). The results indicate that the RE is a promising tool for identifying stratospheric mixing barriers. In Southern Hemisphere winter and early spring, RE produces patterns similar to those found in other studies of stratospheric mixing. High values of RE are found to be indicative of the strong fluctuations in tracer distributions associated with relatively unmixed air in general, and with gradients in the vicinity of mixing barriers, in particular. Lower values suggest more thoroughly mixed air masses. The analysis is extended to eleven years of model data. Realistic inter-annual variability of some of the RE structures is observed, particularly in the Southern Hemisphere. By calculating a climatological mean of the RE for this period, additional mixing patterns are identified in the Northern Hemisphere. The validity of the RE analysis and its interpretation is underlined by showing that qualitatively similar patterns can be seen when using observational satellite data of a different tracer. Compared to previous techniques, the RE has the advantage that it requires significantly less computational effort, as it can be used to derive dynamical information from model or measurement tracer data without relying on any additional input such as wind fields. The results presented in this thesis strongly suggest that the RE is a useful new metric for analysing stratospheric mixing and its variability from climate model data. Furthermore, it is shown that the RE measure is very robust with respect to data gaps, which makes it ideal for application to observations. Hence, using the RE for comparing observations of tracer distributions with those from model simulations potentially presents a novel approach for analysing mixing in the stratosphere.

Nos travaux de thèse portent sur la modélisation et la simulation à base d'agents de systèmes complexes, appliquées au phénomène de propagation de la Schistosomose. Plus particulièrement, nous nous sommes intéressés aux aspects spatiaux et sociaux de la propagation de cette maladie, en utilisant une approche de couplage de modèles à base d'agents. En effet, nous avons initialement étudié la modélisation mathématique de la Schistosomose et la complexité du phénomène de sa propagation. Ce qui nous a permis d'identifier deux dynamiques épidémiologiques (dynamiques spatiale et sociale) sous-jacentes à la propagation de la Schistosomose pour lesquelles, les modèles mathématiques présentent des limites. Cette problématique nous a poussés à étudier isolément ces deux dynamiques et à proposer un modèle multi-agents pour chacune d'elles. Ces deux modèles à base d'agents, représentant deux dynamiques complémentaires d'un même système, ont été implémentés selon des formalismes et des plateformes différentes : un modèle dans GAMA, une plateforme de simulation à base d'agents ; et un autre dans JASON, une plateforme de programmation d'agents BDI (Belief, Desire, Intention). Le modèle GAMA implémente l'aspect comportemental (pour la dynamique spatiale) qui se penche sur la réactivité des individus face à l'environnement physique et le suivi de l'infection. Le modèle JASON implémente l'aspect décisionnel (pour la dynamique sociale) qui introduit la dimension cognitive et mentale des individus en assurant leur capacité de décision et de sélection qui sont déterminées par leur environnement social, culturel, économique, etc. Pour assurer la composition des deux modèles, nous avons proposé une solution de couplage (par Co-simulations) des deux plateformes GAMA et JASON. Nous avons finalement expérimenté le modèle avec un cas de dynamique de propagation de la maladie à Niamey (au Niger) pour lequel les données étaient accessibles. / Our thesis work focuses on agent-based modeling and simulation of complex systems, applied to the spread of schistosomiasis. Specially, we were interested in the spatial and social aspects of the spread of the disease, using an agent-based coupling approach of models.Indeed, we initially studied the mathematical modeling of schistosomiasis and the complexity of its propagation, which allowed us to identify two epidemiological dynamics (spatial and social dynamics) underlying the spread of schistosomiasis for which mathematical models have limits. This problematic led us to study separately these two dynamics and propose an agent-based model for each. These two agent-based models, representing two complementary dynamics of a system, were implemented according different formalisms and different platforms: one model on GAMA (an agent-based simulation platform); and another on JASON (a programming platform of BDI agents). The GAMA model implements the behavioral aspect (for the spatial dynamic) that focuses on individuals reactivity with regards to the physical environment, and the monitoring of the infection. The JASON model implements the decisional aspect (for the social dynamic) that introduces the cognitive and mental dimension of individuals, ensuring their decision and selection capacities which are determined by their social, cultural and economic environment. To ensure the composition of the two models, we proposed an agent-based coupling solution (co-simulation) of the two platforms (GAMA and JASON). We finally experienced the model with a case of dynamic spread of the disease in Niamey (Niger) for which data were available.

A análise de texturas dinâmicas tem se apresentado como uma área de pesquisa crescente e em potencial nos últimos anos em visão computacional. As texturas dinâmicas são sequências de imagens de textura (i.e. vídeo) que representam objetos dinâmicos. Exemplos de texturas dinâmicas são: evolução de colônia de bactérias, crescimento de tecidos do corpo humano, escada rolante em movimento, cachoeiras, fumaça, processo de corrosão de metal, entre outros. Apesar de existirem pesquisas relacionadas com o tema e de resultados promissores, a maioria dos métodos da literatura possui limitações. Além disso, em muitos casos as texturas dinâmicas são resultado de fenômenos complexos, tornando a tarefa de caracterização um desafio ainda maior. Esse cenário requer o desenvolvimento de um paradigma de métodos baseados em complexidade. A complexidade pode ser compreendida como uma medida de irregularidade das texturas dinâmicas, permitindo medir a estrutura dos pixels e quantificar os aspectos espaciais e temporais. Neste contexto, o objetivo deste mestrado é estudar e desenvolver métodos para caracterização de texturas dinâmicas baseado em metodologias de complexidade advindas da área de sistemas complexos. Em particular, duas metodologias já utilizadas em problemas de visão computacional são consideradas: redes complexas e caminhada determinística parcialmente auto-repulsiva. A partir dessas metodologias, três métodos de caracterização de texturas dinâmicas foram desenvolvidos: (i) baseado em difusão em redes - (ii) baseado em caminhada determinística parcialmente auto-repulsiva - (iii) baseado em redes geradas por caminhada determinística parcialmente auto-repulsiva. Os métodos desenvolvidos foram aplicados em problemas de nanotecnologia e tráfego de veículos, apresentando resultados potenciais e contribuindo para o desenvolvimento de ambas áreas. / Dynamic texture analysis has been an area of research increasing and in potential in recent years in computer vision. Dynamic textures are sequences of texture images (i.e. video) that represent dynamic objects. Examples of dynamic textures are: evolution of the colony of bacteria, growth of body tissues, moving escalator, waterfalls, smoke, process of metal corrosion, among others. Although there are researches related to the topic and promising results, most literature methods have limitations. Moreover, in many cases the dynamic textures are the result of complex phenomena, making a characterization task even more challenging. This scenario requires the development of a paradigm of methods based on complexity. The complexity can be understood as a measure of irregularity of the dynamic textures, allowing to measure the structure of the pixels and to quantify the spatial and temporal aspects. In this context, this masters aims to study and develop methods for the characterization of dynamic textures based on methodologies of complexity from the area of complex systems. In particular, two methodologies already used in computer vision problems are considered: complex networks and deterministic walk partially self-repulsive. Based on these methodologies, three methods of characterization of dynamic textures were developed: (i) based on diffusion in networks - (ii) based on deterministic walk partially self-repulsive - (iii) based on networks generated by deterministic walk partially self-repulsive. The developed methods were applied in problems of nanotechnology and vehicle traffic, presenting potencial results and contribuing to the development of both areas.

Les grilles et les clouds sont deux types aujourd'hui largement répandus de systèmes informatiques distribués (en anglais DCS). Ces DCS sont des systèmes complexes au sens où leur comportement global émergent résulte de l'interaction décentralisée de ses composants, et n'est pas guidée directement de manière centralisée. Dans notre étude, nous présentons un modèle de système complexe qui gère de manière la plus efficace possible les ressources d'un DCS. Les entités d'un DCS réagissent à l'instabilité du système et s'ajustent aux conditions environnementales pour optimiser la performance du système. La structure des réseaux d'interaction qui permettent un accès rapide et sécurisé aux ressources disponibles est étudiée, et des améliorations proposées. / Grids and clouds are types of currently widely known distributed computing systems or DCSs. DCSs are complex systems in the sense that their emergent global behavior results from decentralized interaction of its parts and is not guided directly from a central point. In our study, we present a complex system model that efficiently manages the ressources of a DCS. The entities of the DCS react to system instability and adjust their environmental condtions for optimizing system performance. The structure of the interaction networks that allow fast and reliable access to available resources is studied and improvements ar proposed.

This paper presents the cooperative modelling methodology used in the Information Society foresight carried out within the research project SCETIST. The class of models here presented used the concept of group decision creativity that has been elaborated for the use in a Living Lab. The trends and scenarios are discussed and refined during cooperative activities, finally verified using the simulation of a hybrid system consisting of qualitative information processing, and a discretetime- control system with a discrete-event component.