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This master thesis treats the modelling of a common-rail direct fuel injection system where pressure generation is decoupled from the injection process. It has been shown that the fuel pressure plays a vital role for the general performance of the engine, affecting both emissions and efficiency, and it is carefully regulated to achieve optimal performance at different operating points. In an attempt to facilitate the development of the responsible control algorithms, a simulation framework has been requested. A model describing the complete work cycle of the high-pressure fuel system is developed and implemented in a Simulink environment. It is to a large extent based on the underlying physics and constructed in a modular manner, which allows for different engine configurations to be simulated. The modelled pressure signal is compared to experimental data at different operating points with promising results in capturing the transient behaviour from a low-level perspective. Additionally, it manages to replicate some of the pressure oscillations which has been observed in the real system and it shows good response to changes in the input signals. However, there are some areas which are subject to improvement since capturing the static pressure levels over longer drive cycles has proved to be a difficult task. Overall, the developed model serves as a starting point for future development and validation of control algorithms.

Cette thèse vise à concevoir des estimateurs non-asymptotiques et robustes pour les systèmes linéaires d’ordre fractionnaire dans un environnement bruité. Elle traite une classe des systèmes linéaires d’ordre fractionnaire modélisée par la dite pseudo représentation d’état avec des conditions initiales inconnues. Elle suppose également que les systèmes étudiés ici peuvent être transformés sous la forme canonique de Brunovsky. Pour estimer le pseudo-état, la forme précédente est transformée en une équation différentielle linéaire d’ordre fractionnaire en prenant en compte les valeurs initiales des dérivées fractionnaires séquentielles de la sortie. Ensuite, en utilisant la méthode des fonctions modulatrices, les valeurs initiales précédentes et les dérivées fractionnaires avec des ordres commensurables de la sortie sont données par des formules algébriques avec des intégrales à l’aide d’une méthode récursive. Ainsi, ces formules sont utilisés pour calculer le pseudo-état dans le cas continu sans bruit. En outre, elle fournit un algorithme pour construire les fonctions modulatrices requises à l’accomplissement de l’estimation. Deuxièmement, inspiré par la méthode des fonctions modulatrices développée pour l’estimation de pseudo-état, cette méthode algébrique basée sur un opérateur est introduite pour estimer la dérivée fractionnée avec un ordre arbitraire fractionnaire de la sortie pour les systèmes considérés. Cet opérateur sert à annuler les valeurs initiales non désirées, puis permet d’estimer la dérivée fractionnaire souhaitée par une nouvelle formule algébrique à l’aide d’une méthode récursive. Troisièmement, l’estimateur du pseudo-état et le différenciateur d’ordre fractionnaire obtenus précédemment sont étudiés respectivement dans le cas discret et bruité. Chacun d’entre eux contient une erreur numérique due à la méthode d’intégration numérique utilisée et au bruit. En particulier, elle fournit une analyse pour diminuer la contribution du bruit au moyen d’une d’erreur bornée qui permet de sélectionner les degrés optimaux des fonctions de modulation à chaque instant. Ensuite, des exemples numériques sont donnés pour mettre en évidence la précision, la robustesse et la propriété non-asymptotique des estimateurs proposés. En outre, les comparaisons avec certaines méthodes existantes et avec un nouvel observateur d’ordre fractionnaire de typeH1sont montrées. Enfin, elle donne des conclusions / This thesis aims to design non-asymptotic and robust estimators for a class of fractional order linear systems in noisy environment. It deals with a class of commensurate fractional order linear systems modeled by the so-called pseudo-state space representation with unknown initial conditions. It also assumed that linear systems under study can be transformed into the Brunovsky’s observable canonical form. Firstly, the pseudo-state of the considered systems is estimated. For this purpose, the Brunovsky’s observable canonical form is transformed into a fractional order linear differential equation involving the initial values of the fractional sequential derivatives of the output. Then, using the modulating functions method, the former initial values and the fractional derivatives with commensurate orders of the output are given by algebraic integral formulae in a recursive way. Thereby, they are used to calculate the pseudo-state in the continuous noise-free case. Moreover, to perform this estimation, it provides an algorithm to build the required modulating functions. Secondly, inspired by the modulating functions method developed for pseudo-state estimation, an operator based algebraic method is introduced to estimate the fractional derivative with an arbitrary fractional order of the output. This operator is applied to cancel the former initial values and then enables to estimate the desired fractional derivative by a new algebraic formula using a recursive way. Thirdly, the pseudo-state estimator and the fractional order differentiator are studied in discrete noisy case. Each of them contains a numerical error due to the used numerical integration method, and the noise error contribution due to a class of stochastic processes. In particular, it provides ananalysis to decrease noise contribution by means of an error bound that enables to select the optimal degrees of the modulating functions at each instant. Then, several numerical examples are given to highlight the accuracy, the robustness and the non-asymptotic property of the proposed estimators. Moreover, the comparisons to some existing methods and a new fractional orderH1-like observer are shown. Finally, conclusions are outlined with some perspectives

Periodically correlated time series generally exist in several fields including hydrology, climatology, economics and finance, and are commonly modelled using periodic autoregressive (PAR) model. For a time series with stochastic periodic trend, for which a unit root is expected, a periodically integrated autoregressive PIAR model with periodic and/or seasonal unit root has been shown to be a satisfactory model. The existing theory used the multivariate methodology to study PIAR models. However, this theory is convoluted, majority of it only developed for quarterly time series and its generalisation to time series with larger number of periods is quite cumbersome. This thesis studies the existing theory and highlights its restrictions and flaws. It provides a coherent presentation of the steps for analysing PAR and PIAR models for different number of periods. It presents the different unit roots representations and compares the performance of different unit root tests available in literature. The restrictions of existing studies gave us the impetus to develop a unified theory that gives a clear understanding of the integration and unit roots in the periodic models. This theory is based on the spectral information of the multi-companion matrix of the periodic models. It is more general than the existing theory, since it can be applied to any number of periods whereas the existing methods are developed for quarterly time series. Using the multi-companion method, we specify and estimate the periodic models without the need to extract complicated restrictions on the model parameters corresponding to the unit roots, as required by NLS method. The multi-companion estimation method performed well and its performance is equivalent to the NLS estimation method that has been used in the literature. Analysing integrated multivariate models is a problematic issue in time series. The multi-companion theory provides a more general approach than the error correction method that is commonly used to analyse such time series. A modified state state representation for the seasonal periodically integrated autoregressive (SPIAR) model with periodic and seasonal unit roots is presented. Also an alternative state space representations from which the state space representations of PAR, PIAR and the seasonal periodic autoregressive (SPAR) models can be directly obtained is proposed. The seasons of the parameters in these representations have been clearly specified, which guarantees correct estimated parameters. Kalman filter have been used to estimate the parameters of these models and better estimation results are obtained when the initial values were estimated rather than when they were given.

介紹幾種具有良好性質的共積模型估計方法，這些方法因其估計目的不同，而採取相異的模型表示式、相異的估計準則。在論文的連貫性與完整性考量上，須從最簡單的單變數非恆定模型開始介紹整篇論文的基礎。考慮變數間的累積性質關聯，採取空間投影的方法，將共積向量空間、模型虛假迴歸性質、甚至非恆定模型的單根來源連結在一起。充份說明了共積模型裡變數彼此的關聯後，採用共積空間表示式來完備誤差修正表示式裡無法說明的變數相關性。兩種表示式相互配合後，可以建立不同估計方法一致的比較基礎。比較不同估計方法的同時，也系統的介紹幾種估計方法。其中Phillips的完全修正法是主要介紹的估計法，也是後續不同方法間的比較基礎。比較不同方法的異同，主要著重點在於不同方法的估計準則或是修正動機。比較後的結論，可以對照原來方法的估計步驟，唯有暸解不同角度看出的變數性質，才能更精確的掌握估計方法。

[pt] A presente pesquisa estuda a produção do espaço urbano como um fenômeno complexo que se submete às determinações históricas do presente, a partir das transformações na/da cidade em processo de expansão. O urbano é dinâmico e marcado por momentos seja de valorização de novas áreas, seja de desvalorização ou revalorização de outras, determinando novos usos e funções para atender o capital. O espaço urbano é produção social, materializado nas diversas práticas espaciais dos sujeitos que vivenciam a cidade. Investigamos a produção do espaço urbano e o processo de expansão da cidade do Rio de Janeiro para à Zona Oeste, com foco na XXVI Região Administrativa de Guaratiba. O século XXI vem apresentando modelos de gestão com políticas públicas voltadas para as questões externas a cidade, com investimentos que privilegiam grandes obras viárias com forte impacto nas transformações do espaço urbano. O processo de expansão da cidade apresenta duas racionalidades que se complementam. Uma é a racionalidade horizontal que se encontra na dimensão do cotidiano e que promove mudanças nas práticas socioespaciais, atingindo os sujeitos de diversas formas. A outra é a racionalidade vertical caracterizada pela interdependência hierárquica, organizacional, configurada em redes, provocando alterações nos padrões de consumo, na circulação de bens e serviços, como também nas ideias e inovações. Nessa perspectiva propomos um estudo das intervenções que chegam à RA de Guaratiba, promovidas principalmente pelo Estado e pelo mercado imobiliário, alterando significativamente a vida dos seus habitantes, além de demostrar uma reorientação urbana da cidade do Rio de Janeiro. Essa investigação parte das representações dos sujeitos sociais, com base na dialética, a fim de compreender as contradições e os conflitos existentes, tensionados por relações de poder nas múltiplas escalas. A análise dos elementos discursivos dos sujeitos pesquisados evidenciou uma perspectiva de desenvolvimento ligado à modernidade; Guaratiba como área de fronteira para o capital; e a presença de aspectos culturais e sociais na região relacionados à concepção de Sertão Carioca. / [en] This research studies the production of urban space as a complex phenomenon that undergoes the present historical determinations, from the transformations in / of the city in expansion process. The urban is dynamic and marked by moments either of valorization of new areas, of devaluation or revaluation of others, determining new uses and functions to serve the capital. The urban space is social production, materialized in the various spatial practices of the subjects who experience the city. We investigated the production of urban space and the process of expansion from the city of Rio de Janeiro to the West Zone, focusing on the XXVI Guaratiba Administrative Region. The 21st century has been presenting management patterns with public policies focused on issues outside the city, with investments that favour major road works with a strong impact on the transformations of urban space. The city s expansion process introduces two rationalities that complement each other. One is the horizontal rationality that is in the daily dimension and that promotes changes in socio-spatial practices, reaching the subjects in various ways. The other is the vertical rationality characterized by hierarchical, organizational interdependence, configured in networks, causing changes in consumption patterns, in circulation of goods and services, as well as in ideas and innovations. In this perspective we propose a study of the interventions that arrive at the Guaratiba AR, promoted mainly by the State and the real estate market, significantly altering the life of its inhabitants, besides showing an urban reorientation of the city of Rio de Janeiro. This investigation starts from the representations of social subjects, based on dialectics, in order to understand the existent contradictions and conflicts, tensioned by power relations at multiple scales. The analysis of the discursive elements of the research subjects showed a development perspective linked to modernity; Guaratiba as a border area for the capital; and the presence of cultural and social aspects in the region related to the conception of Carioca Backland. / [fr] Cette recherche étudie la production de l espace urbain comme un phénomène complexe qui est soumis aux déterminations historiques du présent, à partir des transformations dans / de la ville en processus d expansion. L urbain est dynamique et marqué par des moments de valorisation de nouvelles zones, ou de dévaluation ou de réévaluation d autres, déterminant de nouveaux usages et fonctions pour servir la capitale. L espace urbain est une production sociale, matérialisée dans les différentes pratiques spatiales des sujets qui habitent de la ville. Nous étudions la production de l espace urbain et le processus d expansion de la ville de Rio de Janeiro à la Zone Ouest, en nous concentrant sur la XXVIème Région Administrative de Guaratiba. Le XXIe siècle a présenté des modèles de gestion avec des politiques publiques centrées sur des questions extérieures à la ville, avec des investissements qui privilégient les grands travaux routiers ayant un fort impact sur les transformations de l espace urbain. Le processus d expansion de la ville présente deux rationalités qui se complètent. L une est la rationalité horizontale qui se trouve dans la dimension de la vie quotidienne et qui favorise les changements dans les pratiques socio-spatiales, en atteignant les sujets de plusieurs façons. L autre est la rationalité verticale caractérisée par une interdépendance hiérarchique et organisationnelle, configurée en réseaux, qui entraîne des changements dans les modes de consommation, dans la circulation des biens et des services, ainsi que dans les idées et les innovations. Dans cette perspective, nous proposons une étude des interventions qui arrivent à la Propriété Guaratiba, promues principalement par l État et le marché immobilier, changeant de manière significative la vie de ses habitants, en plus de montrer une réorientation urbaine de la ville de Rio de Janeiro. Cette recherche part des représentations des sujets sociaux, basées sur la dialectique, pour comprendre les contradictions et les conflits existants, mis en tension par des rapports de pouvoir à des échelles multiples. L analyse des éléments discursifs des sujets étudiés a mis en évidence une perspective de développement liée à la modernité, Guaratiba comme zone frontalière de la capitale, et la présence d aspects culturels et sociaux dans la région liés à la conception du Sertão Carioca.

Permeia a arte do século XIX uma reflexão sobre a perspectiva, o ponto de vista como olhar do sujeito. As construções discursivas de Flaubert subvertem procedimentos convencionais de representação da fala e do pensamento, sua escritura produz ambiguidade e desestabiliza a voz narrativa. Em relatos de viagem, ele desloca a descrição do que contempla (elementos da paisagem urbana ou da natureza, objetos e pessoas) para a descrição do que imagina. Fazendo uso de procedimento semelhante em LÉducation sentimentale, ele constrói cenas a partir do que Frédéric, protagonista do romance, observa ou projeta no espaço. Ele mistura percepções, desejos, lembranças, delírio e imaginação do personagem. Ao expressar a subjetividade de Frédéric, Flaubert cria um efeito de sobreposição de espaços. Esta pesquisa abrange aspectos de gênese textual, o estudo de como imagens e descrições integram a criação literária. Planos e roteiros manuscritos mostram que muitas das ideias de Flaubert começam com uma imagem. / Nineteenth century art is permeated by a reflection on perspective, the subjective viewpoint. Flauberts discursive constructions revolutionize conventional procedures that represent speech and thought. His writing produces ambiguity and throws the narrative voice off balance. In travel journals, he shifts descriptions of what he contemplates (urban landscapes or nature, objects and people) to paint in words what he imagines. Using a similar procedure in LÉducation sentimentale, his scenes are built on what the novels protagonist, Frédéric, observes or projects in space. Flaubert mingles perceptions, desires, memories, delerium and imagination. Through Frédérics subjective eye, Flaubert creates an effect of overlapping spaces. This research encompasses textual aspects; it is a study on how images and descriptions actively participate in literary creation. Manuscripts plans and scenarios show that many of Flauberts ideas begin with images.

The purpose of the current study is to evaluate the territories of the death under the perspective of the perception of residents and frequent visitors of catholic temples from the towns of Laranjeiras and São Cristóvão during the eighteenth century. Therefore, the changes involved with the relation of the society with death were analyzed and, hence, the initial assumption is that the death had drawn the dominant landscape in the towns owing to its direct relationship with the churches-cemeteries. In the current days, towns presenting this sort of landscape, such as São Cristóvão and Laranjeiras in Sergipe, are possible targets of archeological studies. By analyzing the remainder death landscapes in these towns, it is realized how present in the quotidian of people the death was, drawing a different landscape in the current times, once as time gone by, the rituals have gone through changes. These towns shelter a considerable number of churches with gravestones inside and, sometimes,cemeteries outside. Thus, it was evidenced that the sacred spaces of the towns still cover the death territory, notwithstanding a new territory, with new symbols and representations. The pre-existing territory of the death, which had drawn the current archeological landscapes, is now perceived as part of a past that, once considered re-signified history, conceals its own signification. Ultimately, it was verified the existence not simply of a death territory, but also an overlapping of death multi-territories, foe every time a space-territory dissociation is processed, a new space-representation connection is established, revealing a new territory of the death / O presente estudo tem por objetivo avaliar os territórios da morte sob a perspectiva da percepção de moradores e frequentadores de templos católicos das cidades setecentistas de Laranjeiras e São Cristóvão. Para tanto, foram analisadas as mudanças que envolvem a relação da sociedade com a morte e, dessa forma, a premissa inicial é de que a morte formava uma paisagem dominante nas cidades a partir da sua relação direta com as Igrejas-Cemitérios. Nos dias atuais, as cidades com esse tipo de paisagem, como São Cristóvão e Laranjeiras em Sergipe, comportam uma leitura arqueológica. Analisando as paisagens da morte restantes nessas cidades, percebe-se como no passado a morte estava presente no cotidiano das pessoas, conformando uma paisagem diferente dos dias atuais, visto que, no decorrer do tempo os rituais sofreram mudanças. Essas cidades abrigam um número muito grande de Igrejas com lápides no seu interior e, algumas, cemitérios no exterior. Desse modo, verificou-se que o espaço sagrado das cidades ainda abriga o território da morte, porém um novo território com novos símbolos e representações. O antigo território da morte, que formou as atuais paisagens arqueológicas, é percebido como parte de um passado que, como história re-significada, guarda seu significante. Enfim, verificou-se a existência não de um território da morte, mas a sobreposição de multiterritórios da morte, pois sempre que se processa uma separação espaçorepresentação, uma nova aproximação espaço-representação surge, revelando-nos um novo território da morte.

Les études menées permettent de prendre en main un système depuis l’identification jusqu’à la commande robuste des systèmes non entiers. Les principes de la platitude permettent de parvenir à la planification de trajectoire à condition de connaître le modèle du système, d’où l’intérêt de l’identification des paramètres du système. Les principaux travaux de cette thèse concernent l’identification de système par modèles non entiers, la génération et la poursuite robuste de trajectoire par l’application des principes de la platitude aux systèmes non entiers.Le chapitre 1 rappelle les définitions et propriétés de l’opérateur non entier ainsi que les diverses méthodes de représentation d’un système non entier. Le théorème de stabilité est également remémoré. Les algèbres sur les polynômes non entiers et sur les matrices polynômiales non entières sont introduites pour l’extension de la platitude aux systèmes non entiers.Le chapitre 2 porte sur l’identification par modèle non entier. Après un état de l’art sur les méthodes d’identification par modèle non entier, deux contextes sont étudiés : en présence de bruit blanc et en présence de bruit coloré. Dans chaque cas, deux estimateurs optimaux (sur la variance et le biais) sont propos´es : l’un, en supposant une structure du modèle connue et d’ordres de dérivation fixés, et l’autre en combinant des techniques de programmation non linéaire qui optimise à la fois les coefficients et les ordres de dérivation.Le chapitre 3 établit l’extension des principes de la platitude aux systèmes non entiers.La platitude des systèmes non entiers linéaires en proposant différentes approches telles que les fonctions de transfert et la pseudo-représentation d’état par matrices polynômiales est étudiée.La robustesse du suivi de trajectoire est abordée par la commande CRONE. Des exemples de simulations illustrent les développements théoriques de la platitude au travers de la diffusion thermique sur un barreau métallique.Enfin, le chapitre 4 est consacré à la validation des contributions en identification, en planification de trajectoire et en poursuite robuste sur un système non entier réel : un barreau métallique est soumis à un flux de chaleur. / The general theme of the work enables to handle a system, from identification to robust control. Flatness principles tackle path planning unless knowing the system model, hence the system parameter identification necessity. The principal contribution of this thesis deal with system identification by non integer models and with robust path tracking by the use of flatness principles for fractional models.Chapter 1 recalls the definitions and properties of a fractional operator and also the various representation methods of a fractional system. The stability theorem is also brought to mind. Fractional polynomial and fractional polynomial matrice algebras are introduced for the extension of flatness principles for fractional systems.Chapter 2 is about non integer model identification. After a state of the art on system identification by non integer model. Two contexts are considered : in presence of white noise and of colored noise. In each situation, two optimal (in variance and bias sense) estimators are put forward : one, when considering a known model structure with fixed differentiating orders, and another one by combining nonlinear programming technics for the optimization of coefficients and differentiating orders.Chapter 3 establishes the extension of flatness principles to fractional systems. Flatness of linear fractional systems are studied while considering different approaches such as transfer functions or pseudo-state-space representations with polynomial matrices. Path tracking robustness is ensured with CRONE control. Simulation examples display theoretical developments on flatness through thermal diffusion on a metallic rod. Finally, Chapter 4 is devoted to validate the contributions to system identification, to trajectory planning and to robust path tracking on a real fractional system : a metallic rod submitted to a heat flux.

La construction de la représentation de soi est basée sur l'intégration des informations que l'on reçoit des différentes modalités sensorielles telles que les informations visuelles, auditives, tactiles ou proprioceptives. L'interaction entre les actions et les mouvements, et plus récemment les interactions sociales et l'espace ont été étudiées essentiellement au niveau comportemental, moins au niveau fonctionnel et beaucoup reste encore à élucider. En particulier, il est important et essentiel de comprendre exactement quels processus sont impliqués dans la construction d'une représentation spatiale et comment ces processus sont mis en oeuvre, non seulement au niveau local par l'activité de neurones spécifiques, dans une zone corticale spécifique, mais aussi à l'échelle du réseau dans son ensemble ainsi qu'à l'échelle du cerveau entier. Le premier axe de ma thèse s'intéresse à l'espace peripersonnel, qui est l'espace le plus proche de nous et qui représente l'un des sous-espaces fonctionnels de la représentation spatiale. Nous faisons l'hypothèse que ce sont les mêmes régions qui contribuent à la convergence multisensorielle, à la prédiction des conséquences sur le traitement tactile d'une stimulation visuelle approchant le corps et à la construction de l'espace peripersonnel. Pour tester cette hypothèse, nous avons étudié l'effet des aspects prédictifs temporels et spatiaux d'un stimulus visuel dynamique sur la détection du stimulus tactile chez l'Homme (étude comportementale) et le primate non humain (étude en IRM fonctionnelle) ainsi que les bases neuronales de la représentation de l'espace proche et de la représentation de l'espace lointain, chez le primate non humain (étude en IRM fonctionnelle). Nous mettons en évidence l'implication d'un réseau parieto-frontal, essentiellement composé par l'aire intrapariétale ventrale VIP et l'aire prémotrice F4 qui sont activées par ces trois mécanismes différents. Nous proposons que ce réseau traite non seulement la trajectoire de l'objet approchant vis-à-vis du corps, mais qu'il anticipe également ses conséquences sur le corps et prépare des actions de protection en réponse à ce stimulus approchant. Le deuxième axe de ma thèse porte sur la caractérisation de l'étendue de la plasticité dans la représentation visuelle dans le cerveau adulte (par opposition aux premiers stades de plasticité observées autour des périodes critiques du développement) et en particulier, sur des développements méthodologiques permettant de mesurer les changements fins dans le cortex visuel induits par une telle plasticité. Plus précisément, nous avons développé un ensemble de méthodes d'IRM à haute résolution : imagerie fonctionnelle (cartographie visuelle à haute résolution, IRM au repos), pharmacologique (imagerie spectroscopique du GABA) et structurelle (IRM anatomique, DTI basée sur la diffusion des molécules d'eau), afin de définir des mesures de référence pour évaluer les changements induits par la plasticité à différents moments après son induction, à travers une étude longitudinale réalisée chez les mêmes animaux. Certaines de ces méthodes nécessitent encore quelques raffinements et ajustements mais, dans l'ensemble, elles montrent leur potentiel prometteur pour étudier la plasticité chez les primates non humains. Dans l'ensemble, ce travail de thèse a permis de créer un lien fonctionnel entre les études d'IRMf effectuées chez l'Homme et les études d'enregistrement d'électrophysiologies chez le primate non humain. De plus, il entraine de nouvelles stratégies et pistes d'explorations à étudier dans le domaine de la représentation spatiale, à la fois chez l'Homme et le primate non humain / The construction of the representation of self is based on the integration of information received by our different sensory modalities such as visual, auditory, tactile or proprioceptive information. The interaction between actions and movements and more recently social interactions and space are being explored at the behavioral level, but less so at the functional level and much more remains to be elucidated. In particular, it is important and fundamental to understand exactly which processes are involved in space representation and how, not only from a partial view focusing on specific cortical areas and single neuron processes but at the scale of the whole brain and the functional networks. The first axis of my thesis focuses on peripersonal space, that is the space that is closest to us, and represents one of the functional subspaces of spatial representation. We assume that it is the same regions that contribute to multisensory convergence, to the prediction of the consequences of a looming visual stimulus onto tactile processing and to the construction of peripersonal space. To test this hypothesis, we investigated the effect of the temporal and spatial predictive aspects of a dynamical looming visual stimulus onto tactile stimulus detection in humans (behavioral study) and non-human primates (fMRI study); the neural bases of near space and far space representations, in non-human primate (fMRI study). We highlight the involvement of a parieto-frontal network, essentially composed by the ventral intraparietal area VIP, the premotor area F4 as well as striate and extra-striate cortical regions, which are activated by these three different mechanisms. We propose that this network not only processes the trajectory of the looming object with respect to the body, but also anticipates its consequences onto the body and prepares protective actions in response to the looming stimulus. The second axis of my thesis focuses on characterizing the extent of plasticity in the visual representation of the adult brain (as opposed to the early stages around the critical developmental periods) and in particular, how the associated fine-grained changes in the visual cortex can be precisely quantified along multiple dimensions (anatomical, functional, pharmacological). Specifically, we have developed a set of high-resolution MRI methods to assess functional (high-resolution visual mapping fMRI, rs-MRI), pharmacological (GABA spectroscopy imaging) and structural (anatomical MRI, DTI) imaging to define reference measures against which to evaluate the changes induced by plasticity at different times after its induction, through a longitudinal study performed in the same animals. Some of these methods need to be more refined but they show that they are really promising to study plasticity in nonhuman primate. On the whole, this present doctoral research allows to make a functional link between human fMRI studies and monkey single cell recording studies and provides new strategies and explorations to perform on the spatial representation field both in humans and non-human primates