[pt] Pesquisas recentes em Virtualização de Redes focaram no problema conhecido como ossificação da Internet (Anderson et al., 2005), onde múltiplas redes virtuais (Virtual Networks - VN) independentes (Anderson et al., 2005) que exibem um alto grau de autonomia compartilham recursos físicos e podem prover serviços com diferentes graus de qualidade. Nesse sentido, pesquisas na área de Redes de Computadores e Sistemas Distribuídos deram passos evolutivos em repensar o projeto e os princípios arquiteturais de uma VN (Blumenthal e Clark, 2001) (Houidi et al., 2008). Entretanto, até onde sabemos, houve pouca investigação sobre o comportamento autonômico de tais arquiteturas (Prehofer e Bettstetters, 2005) (Movahedi et al., 2012). Sendo assim, esta pesquisa descreve uma tentativa de aplicar princípios de Sistemas Multi-Agentes (Multiagent Systems - MAS) para projetar um modelo autonômico e auto-adaptativo para o gerenciamento de redes virtuais (Virtual Networking Provisioning - VNP). Modelo esse que preenche uma lacuna na atual arquitetura da Internet. Além disso, fornecemos uma análise dos requisitos de um gerenciador auto-adaptativo para projetar um modelo autonômico confiável que é capaz de auto-organizar seus próprios recursos, sem controle, externo, para lidar com mudanças no ambiente. Tal comportamento adaptativo será necessário tendo em vista que a próxima geração da Internet está em evolução. Através da nossa avaliação, demonstramos que o modelo atinge seu propósito principal de auto-organizar uma VN eficientemente, dado que ele é capaz de antecipar cenáris críticos e executar planos adaptativos correspondentes. / [en] Recent research in Network Virtualization has focused on the Internet ossification problem (Anderson et al., 2005) whereby multiple independente virtual networks (VN) (Anderson et al., 2005) that exhibit a high degree of autonomy share physical resources and can provide services with varying degrees of quality. Thus, the Network field has taken evolutionary steps on re-thinking the design and architectural principles of VN (Blumenthal e Clark, 2001) (Houidi et al., 2008). However, to the best of our knowledge, there has been little investigation into the autonomic behaviourof such architectures (Prehofer e Bettstetter, 2005) (Movahedi et all., 2012). This paper describes na attempt to use Multiagent System (MAS) principles to design na autonomic and self-adaptative model for virtual network provisioning (VPN) that fills a gap in the current Internet architecture. In addition, we provide na analysis of the requirements of self-adaptive provisioning for designing a reliable autonomic model that is able to self-organize its own resources, with no external control, in order to cope with environment changes. Such behavior will be required as the next negeneration Internet evolves. Through our evaluation, we demonstrate that the model achieves its main purpose of efficiently self-organizing the VN, since it is able to anticipate critical scenarios and trigger corresponding adaptive plans.

Dans ce manuscrit nous proposons une architecture neuronale d'inspiration corticale, capable de développer un traitement émergent de type auto-organisation. Afin d'implémenter cette architecture neuronale de manière distribuée, nous utilisons le modèle de champs neuronaux dynamiques, un formalisme mathématique générique conçu pour modéliser la compétition des activités neuronales au niveau cortical mésoscopique. Pour analyser en détail les propriétés dynamiques des modèles de référence de ce formalisme, nous proposons un critère formel et un instrument d'évaluation, capable d'examiner et de quantifier le comportement dynamique d'un champ neuronal quelconque dans différents contextes de stimulation. Si cet instrument nous permet de mettre en évidence les avantages pratiques de ces modèles, il nous révèle aussi l'incapacité de ces modèles à conduire l'implantation des processus d'auto-organisation (implémenté par l'architecture décrite) vers des résultats satisfaisants. Ces résultats nous amènent à proposer une alternative aux modèles classiques de champs, basée sur un mécanisme de rétro-inhibition, qui implémente un processus local de régulation neuronale. Grâce à ce mécanisme, le nouveau modèle de champ réussit à implémenter avec succès le processus d'auto-organisation décrit par l'architecture proposée d'inspiration corticale. De plus, une analyse détaillée confirme que ce formalisme garde les caractéristiques dynamiques exhibées par les modèles classiques de champs neuronaux. Ces résultats ouvrent la perspective de développement des architectures de calcul neuronal de traitement d'information pour la conception des solutions logicielles ou robotiques bio-inspirées / In this work we propose a cortically inspired neural architecture capable of developping an emergent process of self-organization. In order to implement this neural architecture in a distributed manner, we use the dynamic neural fields paradigm, a generic mathematical formalism aimed at modeling the competition between the neural activities at a mesoscopic level of the cortical structure. In order to examine in detail the dynamic properties of classical models, we design a formal criterion and an evaluation instrument, capable of analysing and quantifying the dynamic behavior of the any neural field, in specific contexts of stimulation. While this instrument highlights the practical advantages of the usage of such models, it also reveals the inability of these models to help implementing the self-organization process (implemented by the described architecture) with satisfactory results. These results lead us to suggest an alternative to the classical neural field models, based on a back-inhibition model which implements a local process of neural activity regulation. Thanks to this mechanism, the new neural field model is capable of achieving successful results in the implementation of the self-organization process described by our cortically inspired neural architecture. Moreover, a detailed analysis confirms that this new neural field maintains the features of the classical field models. The results described in this thesis open the perspectives for developping neuro-computational architectures for the design of software solutions or biologically-inspired robot applications

Cette thèse considère les réseaux de capteurs sans fil (RCSF) de grande dimension (de l'ordre du million de noeuds). Les questions posées sont les suivantes : comment prédire le bon fonctionnement et calculer avant déploiement les performances d'un tel réseau, sachant qu'aucun simulateur ne peut simuler un réseau de plus de 100 000 noeuds ? Comment assurer sa configuration pour garantir performance, passage à l'échelle, robustesse et durabilité ? La solution proposée dans cette thèse s'appuie sur une architecture de RCSF hétérogène à deux niveaux, dont le niveau inférieur est composé de capteurs et le niveau supérieur de collecteurs. La première contribution est un algorithme d'auto-organisation multi-canal qui permet de partitionner le réseau inférieur en plusieurs sous-réseaux disjoints avec un collecteur et un canal de fréquence par sous-réseau tout en respectant le principe de réutilisation de fréquence. La seconde contribution est l'optimisation du déploiement des collecteurs car leur nombre représente celui des sous-réseaux. Les problèmes traités ont été : l'optimisation des emplacements des puits pour un nombre prédéfini de puits et la minimisation du nombre de puits ou du coût pour un nombre prédéfini de sauts dans les sous-réseaux. Une solution intuitive et appropriée pour assurer à la fois performances réseaux et coût, est de partitionner le réseau inférieur en sous-réseaux équilibrés en nombre de sauts. Pour ce faire, la topologie physique des puits est une répartition géographique régulière en grille (carrée, triangulaire, etc.). Des études théoriques et expérimentales par simulation des modèles de topologie montrent, en fonction des besoins applicatifs et physiques, la méthodologie de choix et le calcul des meilleures solutions de déploiement. / This thesis considers the large-scale wireless sensor network (LSWSN) consisting of million nodes. The questions are: how to predict the good working and to compute before deployment the performances of such a network, knowing that no simulator can simulate a network of more than 100000 nodes? How to ensure its configuration to ensure performance, scalability, robustness and longevity? The solution proposed in this thesis is based on a two-tiered heterogeneous architecture of WSN in which the level 1 is composed of sensors and the level 2 of collectors. The first contribution is a multi-channel self-organization algorithm, which allows partitioning the network of level 1 into several disjointed sub-networks with one collector and one frequency channel while respecting the principle of frequency reuse. The second contribution is to optimize the deployment of collectors because their number represents that of sub-networks. The problems addressed were: the optimization of sinks locations for a predetermined number of sinks, and the minimization of financial cost related of the sinks? number, for a predetermined number of hops in the sub-networks. An intuitive and appropriate solution to ensure both network performance and cost is to partition the network of level 1 into balanced sub-networks in number of hops. To do this, the physical topology of sinks is a regular geographical grid (square, triangular, etc.). Theoretical studies and simulation of topology models show, depending on application requirements (node density, charge application, etc.) and physical (radio range, surveillance zone), the methodology of choice and the computation of the best deployment solutions.

La thèse propose une approche de l'apprentissage temporel par des mécanismes d'auto-organisation à grain fin. Le manuscrit situe dans un premier temps le travail dans la perspective de contribuer à promouvoir une informatique cellulaire. Il s'agit d'une informatique où les calculs se répartissent en un grand nombre de calculs élémentaires, exécutés en parallèle, échangeant de l'information entre eux. Le caractère cellulaire tient à ce qu'en plus d’être à grain fin, une telle architecture assure que les connexions entre calculateurs respectent une topologie spatiale, en accord avec les contraintes des évolutions technologiques futures des matériels. Dans le manuscrit, la plupart des architectures informatiques distribuées sont examinées suivant cette perspective, pour conclure que peu d'entre elles relèvent strictement du paradigme cellulaire.Nous nous sommes intéressé à la capacité d'apprentissage de ces architectures, du fait de l'importance de cette notion dans le domaine connexe des réseaux de neurones par exemple, sans oublier toutefois que les systèmes cellulaires sont par construction des systèmes complexes dynamiques. Cette composante dynamique incontournable a motivé notre focalisation sur l'apprentissage temporel, dont nous avons passé en revue les déclinaisons dans les domaines des réseaux de neurones supervisés et des cartes auto-organisatrices.Nous avons finalement proposé une architecture qui contribue à la promotion du calcul cellulaire en ce sens qu'elle exhibe des propriétés d'auto-organisation pour l'extraction de la représentation des états du système dynamique qui lui fournit ses entrées, même si ces dernières sont ambiguës et ne reflètent que partiellement cet état. Du fait de la présence d'un cluster pour nos simulations, nous avons pu mettre en œuvre une architecture complexe, et voir émerger des phénomènes nouveaux. Sur la base de ces résultats, nous développons une critique qui ouvre des perspectives sur la suite à donner à nos travaux. / The thesis proposes a sequence learning approach that uses the mechanism of fine grain self-organization. The manuscript initially starts by situating this effort in the perspective of contributing to the promotion of cellular computing paradigm in computer science. Computation within this paradigm is divided into a large number of elementary calculations carried out in parallel by computing cells, with information exchange between them.In addition to their fine grain nature, the cellular nature of such architectures lies in the spatial topology of the connections between cells that complies with to the constraints of the technological evolution of hardware in the future. In the manuscript, most of the distributed architecture known in computer science are examined following this perspective, to find that very few of them fall within the cellular paradigm.We are interested in the learning capacity of these architectures, because of the importance of this notion in the related domain of neural networks for example, without forgetting, however, that cellular systems are complex dynamical systems by construction.This inevitable dynamical component has motivated our focus on the learning of temporal sequences, for which we reviewed the different models in the domains of neural networks and self-organization maps.At the end, we proposed an architecture that contributes to the promotion of cellular computing in the sense that it exhibits self-organization properties employed in the extraction of a representation of a dynamical system states that provides the architecture with its entries, even if the latter are ambiguous such that they partially reflect the system state. We profited from an existing supercomputer to simulate complex architecture, that indeed exhibited a new emergent behavior. Based on these results we pursued a critical study that sets the perspective for future work.

Investigamos algumas capacidades computacionais de sistemas constituídos de mapas acoplados. Particularmente, exploramos o uso desses sistemas no tratamento de três problemas: a identificação de simetria de reflexão em imagens planas; a formação de clusters de elementos síncronos em redes com topologias do tipo small-worlds; e a construção de figuras que obedecem a uma regra de composição. Para a identificação de simetria, motivados por modelos biológicos construímos uma rede de mapas em que, acoplamentos locais e globais permitem verificar a simetria de reflexão de uma imagem plana através do sincronismo dos elementos do sistema. Em particular, esse sistema apresenta a habilidade de não requerer sua reinicialização para novas identificações e permite, assim, a identificação de simetrias em cenas que se modificam no tempo. Sistemas estendidos de mapas acoplados são, em geral, construídos conectando-se todos os elementos ou pela formação de uma malha uniforme de conexões. A dinâmica desses sistemas pode apresentar a formação de grupos de elementos síncronos. Esse comportamento de auto-organização pode ser encontrado em diversos sistemas complexos reais que, entretanto e mais comumente, exibem topologias de conexões não uniformes entre seus elementos. Mostramos aqui, a capacidade de mapas acoplados, em diferentes topologias de small-worlds, exibirem a formação de grupos de elementos síncronos com um número de conexões próximo ao das malhas com acoplamento local mas com uma significativa redução da distância média entre os elementos da rede. Por último consideramos o uso de sistemas de mapas como sistemas programáveis. Normalmente, para formação de padrões e figuras no plano, sistemas de funções iteradas são empregados com um conjunto fixo de contrações lineares no plano. Aqui, mostramos a possibilidade do uso de mapas mais gerais na produção de tais padrões e figuras, incluindo estruturas biológicas e fractais. Funções de troca são empregadas para alterar a dinâmica do sistema segundo ou o contexto ou o estado, e fornecem, desse modo, uma forma de programação. / We investigated some computational abilities of systems composed by coupled maps. Here, we explored the use of those systems in dealing with three problems: the identification of reflection symmetry in bidimensional images; the appearing of clusters of synchronous elements in networks with small-worlds topologies; and in constructing figures obeying a composition rule. For the symmetry identification problem, we were motivated by biological models to built a network of coupled maps, with local and global couplings, that verify reflection symmetry of plane images through the synchronism of the elements from the system. In matter, this system presents the ability to perform a new identification without re-initializing the system. This feature allows the identification of symmetries in scenes that can change during the time. In general extended coupled map systems have all elements connected, or the connections lying over a uniform lattice. The dynamics of these systems can present the formation of clusters with synchronous elements. Such auto-organization behavior can be found in several actual complex systems. However, more commonly, these systems do not exhibit uniform connections among their elements. Here, we investigated the capacity of coupled map systems, in different topologies of small-worlds, exhibiting the formation of clusters with synchronous elements, by using a number of connections close to the number in regular lattices but with a significant reduction of the mean distance among their elements. Last we considered the use of systems of maps as programmable systems. Usually, for formation of patterns and geometric figures in the plan, iterated function systems work with a fixed set of linear contractions in the plan. Here, we showed that is possible to use more general maps to the production of patterns and geometric figures, and biological patterns and fractals are generated. Shift functions are used to change the dynamics of the map system due to either the context or the state, giving a way of programming the system.

Orientador: Prof. Dr. Charles Morphy D. Santos / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Programa de Pós-Graduação em Ensino, História, Filosofia das Ciências e Matemática, 2014. / O Darwinismo Universal, conceito desenvolvido pelo biólogo evolucionista Richard Dawkins em 1983, responde positivamente à conjectura "Se existe vida fora da Terra, os organismos evoluem como evoluem os seres vivos da Terra?". No entanto, a complexidade adaptativa centrada na seleção natural, seria por si só, aqui ou em qualquer parte do Universo, suficiente para explicar toda a evolução orgânica? O próprio Charles Darwin defendia um pluralismo explicativo para a evolução. A proposta central do trabalho é discutir se uma definição geral de vida pode estar fundamentada na ideia de seleção natural ou se precisamos rediscutir e estender o conceito de Darwinismo Universal à luz de conceitos tais como a auto-organização, que poderia explicar a origem da ordem biológica a partir de características intrínsecas dos sistemas físico-químicos. Também faz parte do escopo do projeto apontar falhas e indevidas extrapolações do Darwinismo associadas a modelos cosmológicos, assim como a não universalidade do conceito frente a tradicional definição universal de vida. Pela falta de uma definição mais ampla do que é vida, a detecção de bioassinaturas ¿ atributos químicos, físicos ou fisiológicos que denotam, necessariamente, a presença de organismos ¿ torna-se limitada por se restringir apenas àquilo que, independentemente do lugar que ocupa no Universo, passa por um processo natural de seleção darwiniana. Tão logo, deve-se buscar uma compreensão universal da vida como um fenômeno emergente coerente. A expansão do conceito de Darwinismo Universal à luz de uma extensão (ou síntese estendida) da Teoria da Evolução ¿ no componente auto-organização ¿ servirá como arcabouço preliminar para uma filosofia da Biologia apta a abarcar a origem da ordem e diversificação de todas as formas de vida na Terra e para determinar diretrizes as buscas de bioassinaturas. / Universal Darwinism, a concept developed by the evolutionary biologist Richard Dawkins in 1983, responds positively to the conjecture "If life out of Earth exists, does it evolve as Earth¿s living beings do?". Nevertheless, the adaptative complex centered in Darwinian evolution and, therefore, in natural selection, would be by itself, here or at any part of the Universe, sufficient to explain all the organic evolution? Charles Darwin himself used to defend an explicative pluralism for evolution. The main purpose of the present work is to discuss if a general definition of life can be uniquely based on natural selection or whether a new discussion and understanding of the Universal Darwinism under the light of concepts like self-organization is required, which would be able to explain the origin of biological order from physicochemical systems intrinsic characteristics. It is also part of this project¿s scope to point out flaws and improper Darwinism extrapolations associated to cosmological models, as well as the concept¿s non-universality faced with life¿s traditional universal definition. By the lack of a broader definition of life, the detection of biosignatures ¿ chemical, physical or physiological attributes which betoken necessarily, the presence of organisms ¿ becomes limited by restricting only what, independently from where it is located in the universe, undergoes a Darwinian natural selection process. Therefore, it is necessary to search for a universal life comprehension as a coherent emerging phenomenon. The expansion of Universal Darwinism under the light of an extension (or extended synthesis) of the Evolutionary theory ¿ at the self-organization component ¿ will serve as preliminary scaffold for a philosophy of biology able to embrace the origin of order and the diversification of all life forms on Earth, and to determine guidelines for biosignatures searches.

La présente thèse porte sur l’étude de l’auto-organisation induite par laser de nanoparticules (NPs) d’argent dans des couches minces de TiO2. Cette technique laser a été récemment mise au point pour fournir des solutions d'impression originales pour des applications comme l'imagerie polarimétrique, la sécurité ou le design. Ici, nous étudions expérimentalement et théoriquement les différents mécanismes impliqués dans la formation des NPs pour un meilleur contrôle de leur morphologie et de leur organisation. Dans le cas de lasers continus, nos résultats expérimentaux prouvent que la vitesse à laquelle le faisceau laser balaye la surface de l’échantillon est un paramètre crucial pour le contrôle de la taille finale des NPs, et de l’élévation de température induite dans la couche par le laser. La taille des NPs d’argent diminue aux basses vitesses d’écriture, alors que leur croissance est activée par effet thermique et apparait uniquement au-dessus d’un seuil de vitesse. La taille finale des NPs varie dans ce cas de façon non-monotone avec la vitesse de balayage alors que la hausse de température ne cesse de croître. Afin d'expliquer ces phénomènes contre-intuitifs, plusieurs modèles numériques ont été développés qui permettent de simuler la variation de la taille des NPs sous insolation laser dans le domaine spectral du visible. Les résultats théoriques concordent bien avec les observations expérimentales et révèlent que l’origine de ces phénomènes résulte d'interactions complexes entre les différents processus physico-chimiques impliqués dans la formation des NPs. Finalement, cette thèse démontre que l’auto-organisation des NPs à l’échelle sub-longueur d’onde peut être aussi réalisée avec des impulsions laser femto-secondes (fs), et une croissance anisotrope des NPs a été également observée pour une gamme particulière de paramètres laser. La comparaison avec les structures de NPs produites par lasers continus suggère que les impulsions laser fs offrent une meilleure maîtrise des effets thermiques et de la taille des NPs. L'usage de laser fs offre ainsi une nouvelle approche pour transférer ces technologies sur des supports souples comme les papiers ou les plastiques / This doctoral thesis focuses on the study of laser-induced self-organization of Ag nanoparticles (NPs) in TiO2 thin layers. This laser technique was recently developed to provide original printing solutions for applications like active color displays, security, or polarization imaging. Here, we investigate experimentally and theoretically the different mechanisms involved in the NPs formation for a better control of their morphology and organization. In the case of continuous-wave (cw) laser, our experimental results prove that the speed at which the laser scans the sample surface is a crucial parameter to control the NP size and the laser-induced temperature rise. Ag NPs shrink at low scan speed, whereas growth governed by a thermal effect only occurs above a speed threshold. Above this threshold, the size of grown Ag NPs changes in a non-monotonous way with scan speed, whereas laser-induced temperature rise increases with speed. In order to explain these counter-intuitive behaviors, several numerical models have been developed to simulate changes in the size distribution of Ag NPs induced by visible light. Simulation results are in good agreement with experimental observations and reveal the origin of the observed phenomena by collective interactions of various physico-chemical processes involved in the variation of NPs size. Finally, this thesis demonstrates that self-organization of NPs at sub-wavelength scale on large areas can also be performed with femtosecond (fs) laser pulses. Oriented anisotropic growth of NPs has also been observed using a proper selection of laser irradiation parameters. Compared with the cw laser induced structures, fs pulses offer better control of the thermal effect and NP size, which opens the way to transfer these technologies on plastic or paper substrates

The external competitive environments and internal group dynamics of organizations are increasing in complexity resulting in new challenges for organizational leaders to improve performance in underperforming teams. The purpose of this phenomenological study was to address what factors led to high-innovation outcomes in complex adaptive systems using a framework constructed from elements of complexity leadership theory and group dynamics research. An in-depth interviewing approach was used to collect data on the lived experience and meaning the participants attributed to their experiences regarding improved team performance. A total of 21 participants were selected from multiple business settings where their team experienced adaptive tension and improved group cohesion. Their stories were reduced into themes using an inductive process and later analyzed through the lens of complexity leadership theory. The factors that emerged in this study, leveraging tension in the group dynamics enabled through objectivity, roles, alignment, capability, execution, purpose, and work ethic that led to mutual respect, directness, and reliance, offer leaders an effective method for achieving sustained team performance. These factors can be used by organizational leaders to improve team performance and consistency in team outcomes over traditional command and control approaches with a work exchange that benefits individual team members. The findings from this study contribute to social change by improving not only team performance, but also member satisfaction. When leadership is viewed from the perspective of the whole system instead of from the perspective of the individual, the relationships between people emerge as the primary enabling factor for high-innovation outcomes.

Ce travail porte sur la synthèse et l’évaluation de systèmes pi-conjugués en tant matériaux actifs pour des dispositifs opto(électroniques). Un premier chapitre décrit une série d’oligothiophènes cruciformes et leur évaluation dans des dispositifs électrochromes. Le second chapitre décrit la synthèse d’accepteurs moléculaires à base de benzodithiophène et l’analyse de leur potentialités comme matériaux accepteurs dans des cellules solaires organiques. La plus large part du travail porte sur l’analyse des relations structure-propriétés d’une série de petites molécules push-pull comportant un groupe donneur triphénylamine (TPA) relié à un groupe accepteur par un espaceur thiényl. Une première étape a consisté à remplacer l’un des cycles phényles de la TPA par des groupes aromatiques tels que p-fluorophényle, anthryle et naphtyle. Ces modifications ont peu d’influence sur les propriétés électroniques de la molécule mais induisent de large variations des propriétés de transport de charge et de conversion photovoltaïque des matériaux correspondants. Au cours d’une seconde étape l’un des groupes phényles de la TPA a été remplacé par des chaînes alkyle, perfluoroalkyle et oligo(oxyethylene). Les résultats de diffraction X, spectroscopie d’absorption et de fluorescence, génération de second harmonique et électrochimie démontrent que certaines de ces molécules présentent des propriétés d’émission contrôlées par agrégation tandis que les matériaux correspondants se réorganisent spontanément à l’état solide sous forme d’agrégats H ou J dotés de propriétés de transport de charges et de conversion photovoltaïque fortement améliorées et de propriétés d’absorption, d’émission et de génération de second harmonique mécaniquement modulables. / This work deals with the design, synthesis and evaluation of molecular pi-conjugated systems as active materials for (opto)electronics devices. A short first chapter describes three X-shaped oligothiophenes, thecharacterization of their structure and properties and a first evaluation of their performances in electrochromic devices. The second chapter describes the synthesis of molecular acceptors based on a benzodithiophene and the analysis of their potentialities when combined with molecular donors in organic solar cells.The major part of the work is focused on the analysis of structure-properties relationships of a series of smallpush-pull molecules involving di- or tri-arylamine donorblocks linked to an acceptor group by a thienyl bridge. In a first step, a phenyl ring of triphenylamine (TPA) is replaced by p-fluorophenyl, anthryl and naphtyl groups.Optical and electrochemical results show that substitution has little effect at the molecular level but can markedly affect solid-state properties with in particular an improvement of charge-transport and short-circuit current density of solar cells based on these donor materials.In a second step, a phenyl ring of TPA is replaced by alkyl, perfluoroalkyl and oligo(oxyethylene) chains. Results of X-ray diffraction, absorption and photoluminescence spectroscopies, second harmonic generation, and electrochemistry demonstrate that some of these molecules under go aggregation controlled photoluminescence emission wave length while the corresponding materials spontaneous lyre organize in the solid-state to form either H or Jaggregates with enhanced charge mobility, photovoltaic conversion efficiency and mechanically-induced chromism, fluorochromism and NLO-chromism.

Dans de nombreuses métropoles, il n'existe pas de transports collectifs centralisés, publics ou privés. Des solutions alternatives se sont développées grâce à des systèmes de transports artisanaux qui reposent sur l'éclatement de la propriété et l'autonomie des équipages de véhicules. Leur mode d'organisation permet aux transports artisanaux de s'adapter à la demande de manière dynamique. Nous proposons d'analyser les caractéristiques de ces systèmes grâce à la modélisation multi-agents et les théories de l'auto-organisation. A travers plusieurs modèles, nous verrons comment les structures et les dynamiques de ces systèmes dépendent des stratégies individuelles et de la structure urbaine. A travers la question de l'adaptabilité du transport en commun, les transports artisanaux nous amènent à nous interroger sur les dimensions urbaines de la mobilité collective mais également sur la flexibilisation des services de transport. / Several metropolises have not any centralized collective transport system, neither private nor public. Alternative solutions appeared, their caracteristics are principally that the ownership is spread out and the vehicle crew is self-directed. The mode of organization of these transports allows them to adapt dynamically to the demand.We propose to analyse the caracteristics of these systems by means of multi-agents modeling and self-organization theory. Using several models, we show how structures and dynamics of these systems are linked to individual strategies and urban structure.Through the question of adaptability of collective transport, small-scale transports led to concern about urban dimensions of collective mobility and flexibilisation of transport services.