Aujourd'hui, la qualité perçue d'un produit arbitre de plus en plus le choix du consommateur. Au-delà<br />des performances techniques, les perceptions du client deviennent très influentes dans la décision d'achat.<br />Dans cette thèse, nous proposons une démarche de conception ” orientée client ”, qui permet d'intégrer le<br />consommateur dans les différentes étapes du processus de conception en prenant en compte ses besoins et<br />ses préférences. Dans notre étude, nous appliquons cette démarche à la facture d'instruments de musique,<br />produits pour lesquels les sensations de l'utilisateur sont primordiales et doivent être intégrées lors de la<br />conception/amélioration d'un instrument. Pour étudier ces données perceptives, nous utilisons l'analyse<br />sensorielle et montrons son intégration dans le processus de conception. Notre démarche consiste, dans un premier temps, à mener une étude perceptive sur une famille de trompettes en utilisant un panel d'experts<br />et les outils de l'analyse sensorielle. Ensuite, nous réalisons une étude objective des instruments par la<br />mesure physique d'une grandeur caractéristique : l'impédance d'entrée. Puis, nous utilisons l'analyse de<br />données pour mettre en regard les évaluations perceptives et objectives, afin d'en déduire des règles utiles pour l'optimisation et la re-conception d'un instrument. Enfin, nous proposons d'intégrer des outils de réalité virtuelle dans le processus de conception centrée utilisateur. Ainsi, dans notre application, nous<br />présentons les premières conclusions concernant les simulations sonores par modèle physique.

La vision perceptive humaine combine différents niveaux de perception pour faciliter l'interprétation d'une scène. Les physiologistes la modélisent par le cycle perceptif, guidé par un facteur psychologique, l'attention visuelle. Ce fonctionnement est à la base de nos travaux sur une méthode générique pour l'analyse de documents structurés. Dans ce contexte, nous proposons le formalisme de calque perceptif ainsi que des outils de multirésolution, pour simuler le cycle perceptif et l'attention visuelle. Le formalisme du calque perceptif permet de fusionner des informations issues de différents niveaux de perception, en étant guidé par des connaissances. Nous aboutissons ainsi à une architecture complète de vision perceptive, DMOS-P, qui est un enrichissement de la méthode DMOS de reconnaissance de documents. Grâce à cette méthode, il devient possible de spécifier simplement des mécanismes complexes de coopération perceptive, adaptés à chaque type de problème, qui améliorent la reconnaissance de la structure de documents. Nous mettons en évidence un mécanisme de prédiction/vérification lié à la vision perceptive : la vision à basse résolution permet d'émettre des hypothèses sur la structure en utilisant le contexte global ; ces hypothèses sont ensuite vérifiées à plus haute résolution. Ce mécanisme simplifie et améliore la reconnaissance des documents : lorsque les indices visuels sont denses (documents bruités ou à structure complexe), la vision perceptive permet de mieux sélectionner les données structurelles pertinentes ; lorsque l'information structurelle est physiquement diuse (documents ayant une structure pauvre), la vision perceptive permet de mieux reconstituer la structure du document. Nous avons validé cette approche sur des documents à structure variée (courriers manuscrits, registres d'archives, presse. . .), à grande échelle (plus de 80 000 images), et de manière industrielle grâce au transfert technologique vers la société Evodia.

Cette thèse est consacrée à la perception visuelle des mouvements humains. L'objectif est de démontrer l'existence de liaisons fonctionnelles entre la perception et la motricité en utilisant des données issues de l'imagerie cérébrale, de l'étude de cas clinique (maladie de Parkinson) et de l'analyse comportementale de sujets adultes et d'enfants. Dans un premier temps, les recherches ont consisté à identifier les structures assurant ces liaisons fonctionnelles. La tomographie par émission de positon est utilisée pour révéler les réseaux neuronaux activés lors de la perception visuelle des mouvements d'écriture et de pointage. Les résultats indiquent que la perception de ces deux catégories de mouvements implique des structures distinctes ayants un rôle dans la planification et l'exécution de ces mouvements. Dans un second temps, les recherches ont consisté à préciser le rôle de ces liens entre perception et motricité. Dans ce but, nous nous sommes plus particulièrement intéressés à un phénomène de préférence perceptive pour la vitesse, dans le cas des mouvements de traçage et de pointage. Après avoir démontré et analysé en détail ce phénomène de préférence perceptive, nous avons étudié la façon dont ces préférences sont modulées en fonction de la représentation que le sujet a du mouvement, de la longueur de la trajectoire, du type de mouvement, du niveau de développement moteur, et de l'état du système moteur des sujets (maladie de Parkinson). Les résultats principaux montrent que : 1) les valeurs des périodes préférées pour un cycle du mouvement révèlent l'existence d'une tendance centrale dans les choix ; 2) les périodes préférées sont comparables aux périodes des mouvements imaginés ; 3) la modulation de la période de référence du sujet dépend, comme dans le cas de l'exécution des mouvements, d'un tempo et d'un paramètre d'échelle ; 4) les valeurs de ces paramètres dépendent du type de mouvement, pour la perception comme pour l'action. Cet ensemble de données permet de penser que la préférence perceptive s'appuie sur un processus de simulation motrice intériorisée du mouvement perçu se déroulant à un niveau implicite. La préférence perceptive pour la vitesse serait la manifestation d'une tendance naturelle du sujet à préférer des stimuli dynamiques conformes à sa propre motricité.

Digital watermarking is the art of embedding secret messages in multimedia contents in order to protect their intellectual property. While the watermarking of image, audio and video is reaching maturity, the watermarking of 3D virtual objects is still a technology in its infancy. In this thesis, we focus on two main issues. The first one is the perception of the distortions caused by the watermarking process or by attacks on the surface of a 3D model. The second one concerns the development of techniques able to retrieve a watermark without the availability of the original data and after common manipulations and attacks. Since imperceptibility is a strong requirement, assessing the visual perception of the distortions that a 3D model undergoes in the watermarking pipeline is a key issue. In this thesis, we propose an image-based metric that relies on the comparison of 2D views with a Mutual Information criterion. A psychovisual experiment has validated the results of this metric for the most common watermarking attacks. The other issue this thesis deals with is the blind and robust watermarking of 3D shapes. In this context, three different watermarking schemes are proposed. These schemes differ by the classes of 3D watermarking attacks they are able to resist to. The first scheme is based on the extension of spectral decomposition to 3D models. This approach leads to robustness against imperceptible geometric deformations. The weakness of this technique is mainly related to resampling or cropping attacks. The second scheme extends the first to resampling by making use of the automatic multiscale detection of robust umbilical points. The third scheme then addresses the cropping attack by detecting robust prong feature points to locally embed a watermark in the spatial domain.

Si l'accès des personnes aveugles aux technologies numériques a été, ces dernières années, grandement facilité, cet accès reste cependant problématique compte tenu des difficultés importantes à interagir avec les objets graphiques, Dans ce contexte, le Groupe Suppléance Perceptive développe depuis plusieurs années une plate-forme haptique (Tactos) devant favoriser cette interactivité avec les objets graphiques. Le travail mené dans le cadre de cette thèse vise, sur la base d'un premier prototype, à la fois à définir les conditions de son appropriation et de son usage par des personnes aveugles et à proposer un ensemble de spécifications pour la conception des futures versions de Tactos. Notre analyse a plus particulièrement porté sur l'identification de stratégies exploratoires efficientes favorisant l'activité perceptive. La méthodologie employée, inscrite dans une approche constructiviste, met à l'épreuve une démarche de conception minimaliste : le premier prototype est initialement restreint pour mieux caractériser des strategies qui, à leur tour, servent à inspirer la conception. Une étude longitudinale, entreprise auprès de six partenaires aveugles, permet de systématiser l'analyse des capacités perceptives et leur évolution. Les résultats mettent en évidence le caractère décisif de la technique exploratoire et l'avantage d'une comparaison entre la situation traditionnelle de lecture de formes et les explorations médiatisées. Les pistes de conception envisagées associent à la fois technologie de suppléance, l'assistance à l'activité et l'enseignement de stratégies spécifiques.

Esta tese é o resultado de uma análise sobre como um grupo de professoras em condições perceptivas distintas escreve, quando se envolvem em uma experiência de escritura na convergência de mídias. Trata-se de um estudo de natureza qualitativa que busca produzir uma análise exploratória embasado principalmente nas Teorias da Biologia do Conhecer de Humberto Maturana e na Teoria da enação de Francisco Varela, no que se referem ao modo de observar e explicar um fenômeno a partir de uma experiência de escritura. A recursividade constitutiva entre escrita e tecnologia é descrita por vários autores, demonstrando que as tecnologias se transformam em ferramentas que modulam os modos de escrever. Situamos o trabalho no campo da Antropologia da Escritura, ao mantermos um diálogo entre alguns de seus autores, dentre os quais destacamos Jack Goody, Jacques Derrida, Roger Chartier e Béatrice Fraenkel. A discussão sobre os modos de viver-conhecer no encontro com diferenças perceptivas visuais e auditivas está embasada principalmente nas obras de Bernard Mottez, Brigitte Garcia, Yves Delaporte e Zina Weygand. O principal foco da investigação foi acompanhar as modalidades de escritura que as professoras – ouvintes e videntes, no encontro com uma professora cega e uma professora surda – realizaram ao se propor a produzir um hiperdocumento coletivo. Para análise da experiência, foi produzido um mapeamento da rede de escrituras tecida pelas professoras em fóruns e salas de bate-papo em ambiente virtual. Os principais marcadores dessa análise qualitativa e exploratória foram as escritas recorrentes e, principalmente, as questões que as professoras formulavam a si e ao grupo na atividade de escrita ou de comentar sobre a escrita feita. Uma diversidade de fonte de informações compõe este mapeamento e subsidiou a análise: filmagens de oficinas organizadas durante a experiência de criação de uma escritura digital, conversações escritas em fóruns e salas de bate-papo na Internet, recortes de diferentes versões da produção de escritas para o hiperdocumento e anotações de campo. As práticas de composição escrita na Internet provocam mudanças nas coordenações de ações, permitindo o encontro entre pessoas que antes não poderiam produzir algo juntas. Estas mudanças nas coordenações de ações, ao envolver um trabalho de manipulação e edição de diferentes mídias - imagens, sons, textos e a Língua de Sinais – faz com que surja uma nova experiência de escritura, implicando em mudanças cognitivas, afetivas e estéticas. Atos de escritura coletiva e digital podem produzir uma convergência interativa na qual existem grandes possibilidades de interlocução entre pessoas com diferentes condições perceptivas, pois mudam os modos sensório-motores de acoplamento com a escrita e as coordenações de ações na rede de conversações escritas tecidas pelas professoras. / This thesis is the outcome of an analysis on how a group of teachers with distinctive perceptive conditions, write when involved in a writing experience with media convergence. It is a study of a qualitative nature and aims to produce an exploratory analysis based, especially in Humberto Maturana’s biology of knowledge and Francisco Varela’s enation theory, and the way they refer to a mode of observation to explain a phenomenon from a writing experience angle. The constituent recursivity between writing and technology is described by many authors, showing that the technologies transform it selves in tools that modulate writing procedures. We situate this work in the field study of Anthropology of Writing with the dialogue established some of its main authors, among which we highlight Jack Goody, J. Derrida, Roger Chartier and Béatrice Fraenkel. The discussion on the livingknowing modes when faced with visual-perceptive and hearing differences is based, chiefly, on the works of Bernard Mottez, Brigitte Garcia, Yves Delaporte and Zina Weygand. The main focus of the investigation was a follow through on the writing modes by which the seeing-writing teachers produced on their encounter with a blind and a deaf teachers in a cognitive hyper-document. For analytic purposes a writing net chart was created to follow the lines produced by these teachers in forums and chat rooms in a virtual ambient. The main markers of the qualitative and exploratory analysis were the recurrent writing processes and, mainly, the questions formulated by the teachers to themselves and the group about the activity of writing itself or on comments on its contents. A variety of information sources consists this charting and base the analysis. The footage of workshop activities organized during the experience of creating a digital writing, thus allowing the encounter of subjects that previously would be unable to produce something together. This shifts in actions coordination, while involving the editing of different media-image, sounds, texts and Sign Language-enable the uprising of a new form of writing, thus implying cognitive, affective and aesthetic changes. Acts of collective digital writing may produce an interactive convergence in which exists great possibilities of interlocution between people with different perceptive conditions once they change the motor-sensorial binding with writing and the action co ordinations on the conversational net weaved by the teachers.

Esta tese é o resultado de uma análise sobre como um grupo de professoras em condições perceptivas distintas escreve, quando se envolvem em uma experiência de escritura na convergência de mídias. Trata-se de um estudo de natureza qualitativa que busca produzir uma análise exploratória embasado principalmente nas Teorias da Biologia do Conhecer de Humberto Maturana e na Teoria da enação de Francisco Varela, no que se referem ao modo de observar e explicar um fenômeno a partir de uma experiência de escritura. A recursividade constitutiva entre escrita e tecnologia é descrita por vários autores, demonstrando que as tecnologias se transformam em ferramentas que modulam os modos de escrever. Situamos o trabalho no campo da Antropologia da Escritura, ao mantermos um diálogo entre alguns de seus autores, dentre os quais destacamos Jack Goody, Jacques Derrida, Roger Chartier e Béatrice Fraenkel. A discussão sobre os modos de viver-conhecer no encontro com diferenças perceptivas visuais e auditivas está embasada principalmente nas obras de Bernard Mottez, Brigitte Garcia, Yves Delaporte e Zina Weygand. O principal foco da investigação foi acompanhar as modalidades de escritura que as professoras – ouvintes e videntes, no encontro com uma professora cega e uma professora surda – realizaram ao se propor a produzir um hiperdocumento coletivo. Para análise da experiência, foi produzido um mapeamento da rede de escrituras tecida pelas professoras em fóruns e salas de bate-papo em ambiente virtual. Os principais marcadores dessa análise qualitativa e exploratória foram as escritas recorrentes e, principalmente, as questões que as professoras formulavam a si e ao grupo na atividade de escrita ou de comentar sobre a escrita feita. Uma diversidade de fonte de informações compõe este mapeamento e subsidiou a análise: filmagens de oficinas organizadas durante a experiência de criação de uma escritura digital, conversações escritas em fóruns e salas de bate-papo na Internet, recortes de diferentes versões da produção de escritas para o hiperdocumento e anotações de campo. As práticas de composição escrita na Internet provocam mudanças nas coordenações de ações, permitindo o encontro entre pessoas que antes não poderiam produzir algo juntas. Estas mudanças nas coordenações de ações, ao envolver um trabalho de manipulação e edição de diferentes mídias - imagens, sons, textos e a Língua de Sinais – faz com que surja uma nova experiência de escritura, implicando em mudanças cognitivas, afetivas e estéticas. Atos de escritura coletiva e digital podem produzir uma convergência interativa na qual existem grandes possibilidades de interlocução entre pessoas com diferentes condições perceptivas, pois mudam os modos sensório-motores de acoplamento com a escrita e as coordenações de ações na rede de conversações escritas tecidas pelas professoras. / This thesis is the outcome of an analysis on how a group of teachers with distinctive perceptive conditions, write when involved in a writing experience with media convergence. It is a study of a qualitative nature and aims to produce an exploratory analysis based, especially in Humberto Maturana’s biology of knowledge and Francisco Varela’s enation theory, and the way they refer to a mode of observation to explain a phenomenon from a writing experience angle. The constituent recursivity between writing and technology is described by many authors, showing that the technologies transform it selves in tools that modulate writing procedures. We situate this work in the field study of Anthropology of Writing with the dialogue established some of its main authors, among which we highlight Jack Goody, J. Derrida, Roger Chartier and Béatrice Fraenkel. The discussion on the livingknowing modes when faced with visual-perceptive and hearing differences is based, chiefly, on the works of Bernard Mottez, Brigitte Garcia, Yves Delaporte and Zina Weygand. The main focus of the investigation was a follow through on the writing modes by which the seeing-writing teachers produced on their encounter with a blind and a deaf teachers in a cognitive hyper-document. For analytic purposes a writing net chart was created to follow the lines produced by these teachers in forums and chat rooms in a virtual ambient. The main markers of the qualitative and exploratory analysis were the recurrent writing processes and, mainly, the questions formulated by the teachers to themselves and the group about the activity of writing itself or on comments on its contents. A variety of information sources consists this charting and base the analysis. The footage of workshop activities organized during the experience of creating a digital writing, thus allowing the encounter of subjects that previously would be unable to produce something together. This shifts in actions coordination, while involving the editing of different media-image, sounds, texts and Sign Language-enable the uprising of a new form of writing, thus implying cognitive, affective and aesthetic changes. Acts of collective digital writing may produce an interactive convergence in which exists great possibilities of interlocution between people with different perceptive conditions once they change the motor-sensorial binding with writing and the action co ordinations on the conversational net weaved by the teachers.

Esta tese é o resultado de uma análise sobre como um grupo de professoras em condições perceptivas distintas escreve, quando se envolvem em uma experiência de escritura na convergência de mídias. Trata-se de um estudo de natureza qualitativa que busca produzir uma análise exploratória embasado principalmente nas Teorias da Biologia do Conhecer de Humberto Maturana e na Teoria da enação de Francisco Varela, no que se referem ao modo de observar e explicar um fenômeno a partir de uma experiência de escritura. A recursividade constitutiva entre escrita e tecnologia é descrita por vários autores, demonstrando que as tecnologias se transformam em ferramentas que modulam os modos de escrever. Situamos o trabalho no campo da Antropologia da Escritura, ao mantermos um diálogo entre alguns de seus autores, dentre os quais destacamos Jack Goody, Jacques Derrida, Roger Chartier e Béatrice Fraenkel. A discussão sobre os modos de viver-conhecer no encontro com diferenças perceptivas visuais e auditivas está embasada principalmente nas obras de Bernard Mottez, Brigitte Garcia, Yves Delaporte e Zina Weygand. O principal foco da investigação foi acompanhar as modalidades de escritura que as professoras – ouvintes e videntes, no encontro com uma professora cega e uma professora surda – realizaram ao se propor a produzir um hiperdocumento coletivo. Para análise da experiência, foi produzido um mapeamento da rede de escrituras tecida pelas professoras em fóruns e salas de bate-papo em ambiente virtual. Os principais marcadores dessa análise qualitativa e exploratória foram as escritas recorrentes e, principalmente, as questões que as professoras formulavam a si e ao grupo na atividade de escrita ou de comentar sobre a escrita feita. Uma diversidade de fonte de informações compõe este mapeamento e subsidiou a análise: filmagens de oficinas organizadas durante a experiência de criação de uma escritura digital, conversações escritas em fóruns e salas de bate-papo na Internet, recortes de diferentes versões da produção de escritas para o hiperdocumento e anotações de campo. As práticas de composição escrita na Internet provocam mudanças nas coordenações de ações, permitindo o encontro entre pessoas que antes não poderiam produzir algo juntas. Estas mudanças nas coordenações de ações, ao envolver um trabalho de manipulação e edição de diferentes mídias - imagens, sons, textos e a Língua de Sinais – faz com que surja uma nova experiência de escritura, implicando em mudanças cognitivas, afetivas e estéticas. Atos de escritura coletiva e digital podem produzir uma convergência interativa na qual existem grandes possibilidades de interlocução entre pessoas com diferentes condições perceptivas, pois mudam os modos sensório-motores de acoplamento com a escrita e as coordenações de ações na rede de conversações escritas tecidas pelas professoras. / This thesis is the outcome of an analysis on how a group of teachers with distinctive perceptive conditions, write when involved in a writing experience with media convergence. It is a study of a qualitative nature and aims to produce an exploratory analysis based, especially in Humberto Maturana’s biology of knowledge and Francisco Varela’s enation theory, and the way they refer to a mode of observation to explain a phenomenon from a writing experience angle. The constituent recursivity between writing and technology is described by many authors, showing that the technologies transform it selves in tools that modulate writing procedures. We situate this work in the field study of Anthropology of Writing with the dialogue established some of its main authors, among which we highlight Jack Goody, J. Derrida, Roger Chartier and Béatrice Fraenkel. The discussion on the livingknowing modes when faced with visual-perceptive and hearing differences is based, chiefly, on the works of Bernard Mottez, Brigitte Garcia, Yves Delaporte and Zina Weygand. The main focus of the investigation was a follow through on the writing modes by which the seeing-writing teachers produced on their encounter with a blind and a deaf teachers in a cognitive hyper-document. For analytic purposes a writing net chart was created to follow the lines produced by these teachers in forums and chat rooms in a virtual ambient. The main markers of the qualitative and exploratory analysis were the recurrent writing processes and, mainly, the questions formulated by the teachers to themselves and the group about the activity of writing itself or on comments on its contents. A variety of information sources consists this charting and base the analysis. The footage of workshop activities organized during the experience of creating a digital writing, thus allowing the encounter of subjects that previously would be unable to produce something together. This shifts in actions coordination, while involving the editing of different media-image, sounds, texts and Sign Language-enable the uprising of a new form of writing, thus implying cognitive, affective and aesthetic changes. Acts of collective digital writing may produce an interactive convergence in which exists great possibilities of interlocution between people with different perceptive conditions once they change the motor-sensorial binding with writing and the action co ordinations on the conversational net weaved by the teachers.

L’activité de conduite automobile prend place dans un environnement dynamique en constante évolution. Le conducteur doit progresser sur la route au moyen de son véhicule, tout en interagissant adéquatement avec l'environnement et les autres usagers. Pour réaliser cette tâche, le conducteur doit percevoir son environnement, interpréter les événements pour se représenter correctement la situation de conduite, anticiper ces changements, et prendre des décisions afin d'engager des actions sur le véhicule lui permettant d'atteindre les buts qu'il se fixe à court et long terme. A cet égard, la complexité et la diversité des processus perceptifs, cognitifs et sensori-moteurs requis pour la conduite automobile font de cette activité un objet d'étude particulièrement riche pour les sciences de la cognition.Pour étudier l'activité du conducteur automobile afin de la comprendre, l'expliquer et peut-être la prédire, les sciences cognitives se dirigent vers la modélisation de la cognition humaine. Cette démarche permet une représentation et une description plus ou moins fine du système cognitif du conducteur automobile. Cependant, un modèle de la cognition ne permet qu'une description théorique. Grâce à son implémentation informatique, il devient possible de simuler les théories utilisées et déployer numériquement celles mises en jeu dans la modélisation cognitive.Ce travail de thèse s'articule autour de la modélisation cognitive du conducteur automobile, de son implémentation informatique sur une plateforme de développement virtuel et de sa simulation au sein de cette plateforme. Le modèle théorique que nous avons implémenté est COSMODRIVE, en développement au laboratoire du LESCOT à l'IFSTTAR, et la plateforme de développement accueillant le modèle est SIVIC, développée au LIVIC. C'est dans ce contexte que nous nous sommes engagés dans le développement computationnel et informatique du modèle COSMODRIVE, afin de pouvoir simuler l'activité perceptive et cognitive du conducteur automobile. Pour cela, nous nous sommes limités à certains processus cognitifs primordiaux, comme les fonctions stratégiques (planification d'itinéraires et réalisation de plans stratégiques), ou les fonctions perceptives (exploration et intégration de l'information visuelle), les fonctions cognitives tactiques (construction de représentations mentales, intégration perceptivo-cognitive de l'information, structuration des connaissances de conduite, etc), ou encore les fonctions d'exécution d'actions (régulation courte par zones enveloppes ou par points de poursuite).Par l'implémentation informatique du modèle COSMODRIVE sur SIVIC, il devient possible "d'incarner numériquement" des théories cognitives et de les "opérationnaliser" pour formuler des hypothèses de recherche sous la forme de prédictions de performances que l'on pourra évaluer empiriquement auprès de conducteurs humains. Ces hypothèses formulées, nous avons conduit des expérimentations sur un simulateur de conduite que nous avons construit. Afin d'éprouver notre modèle théorique et informatique du conducteur, nous avons comparé les performances des conducteurs humains avec les prédictions issues de la simulation. Les résultats obtenus ont permis de valider cette approche et de confirmer l'intérêt de la simulation cognitive pour appréhender les activités mentales du conducteur automobile. / Driving activity takes place in a dynamic and constantly changing environment. The driver has to make his car evolving on the road while ensuring adequate interactions with its close environment and other road users. In order to perform this task, the driver has to perceive the environment he is evolving in, to interpret events in order to correctly understand the current driving situation, to be able to anticipate its evolution and take decisions regarding vehicle control in order to reach his short and long term goals safely. As a result, both complexity and variety of perceptual, cognitive and sensorimotor processes involved in the driving activity make it very rich context for cognitive sciences.The modeling of human cognition, a specific method which belongs to cognitive sciences field, has been chosen to study driver's activity aiming at understanding, explaining or even predicting it. This approach allows a representation and a description of the driver's cognitive system with different levels of granularity. Thus, such a model offers only a theoretical description. When implemented on a computer, it opens the way to the simulation allowing the digital deployment of the theories involved in the cognitive model design.This thesis is focused on cognitive modeling of car driver, its implementation and its simulation using a virtual platform. The theoretical model that we implemented is COSMODRIVE, developed at IFSTTAR - LESCOT laboratory and the implementation platform we used for this, named SIVIC, is developed at IFSTTAR - LIVIC.This is the context where we started the computational development of the COSMODRIVE model in order to simulate the perceptual and cognitive activity of car driver. Indeed, we chose to limit our implementation to some crucial cognitive processes such as strategic functions (route planning and strategic plans execution), perceptual functions (exploration and integration of visual information), cognitive tactical functions (construction of mental representations, perceptual and cognitive integration of information, structuring of driving knowledge, etc.), or executive functions of actions (short control loop by ''envelopes zones'' or pursuit points).Through computer simulation, we used the numerical model as an innovative tool for scientific investigation in the field of cognitive sciences: The numerical simulation of cognitive functions identified and modeled by COSMODRIVE allowed us to define experimental hypotheses which leed us to conduct experiments in a driving simulator that we have built. To test the theoretical model and computer of the car driver, we compared the performance of human drivers on one hand and the predictions issued from the simulation on the other hand. It opens innovative opportunities for the development and the use of cognitive modeling and simulation of car driver.

No / Purpose: Does a physiologically plausible model of the retinal ganglion cell (RGC) receptive field (RF) predict the spatial tuning properties of the Hermann Grid Illusion (HGI)? Methods: The spatial tuning of a single intersection HGI was measured psychophysically in normal observers using a nulling technique at different vertical grid line luminances. We used a model based upon a standard RGC RF, balanced to produce zero response under uniform illumination, to predict the response of the model cell to the equivalent range of stimulus conditions when placed in either the 'street' or the 'intersection' of a single element of a Hermann grid. We determined the equivalent of the nulling luminance required to balance these responses and minimise the HGI. Results: The model and the psychophysical data demonstrated broad spatial tuning with similarly shaped tuning profiles and similar strengths of illusion. The line width at the peak of the model tuning function was around twice the model RGC RF centre size. Modelling the psychophysical functions gave RF centre sizes smaller than expected from human anatomical evidence but similar to that suggested by primate physiological evidence. In the model and psychophysically the strength of the illusion varied with the luminance of the vertical grid line when HGI strength was expressed as a Michelson nulling contrast, but this effect was smaller when HGI strength was expressed as a nulling luminance. Conclusions: The shape, width, height and position of the spatial tuning function of the HGI can be well modelled by a RGC RF based model. The broad tuning of these functions does not appear to require a broad range of different cell sizes either in the retina or later in the visual pathway.