Dissertations / Theses on the topic 'Conception de formes aérodynamiques'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Conception de formes aérodynamiques.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Chetboun, Jonathan. "Conception de formes aérodynamiques en présence d'écoulements décollés : contrôle et optimisation." Phd thesis, Ecole Polytechnique X, 2010. http://pastel.archives-ouvertes.fr/pastel-00550726.
Full textGiner, Pierre. "Simulation numérique des jets et sillages instationnaires dans la conception de formes aérodynamiques." Thesis, Toulouse, ISAE, 2012. http://www.theses.fr/2012ESAE0015.
Full textThe aerodynamic integration of Ultra-High Bypass Ratio turbofans raises the need for an accurate prediction of the unsteady properties of the jet development using Computational Fluid Dynamics, since the design stages. The ability of numerical methods in predicting these phenomena are assessed in this thesis, using different modelling approaches. A dual-stream jet configuration is investigated, using an associated wind-tunnel test campaign. Reynolds-Averaged Navier-Stokes simulations, using several turbulence models, are shown to correctly reproduce the mean flow especially concerning the shear layers. Shock cells and turbulence levels predictions within the primary and secondary jet flows are however perfectible compared to the test results. Turbulence-accounting approaches based upon experimental data and using different configurations partially overcome this issue. An unsteady methodis then applied in order to resolve turbulent phenomena instead of modelling them. The hybrid Detached-Eddy Simulation of the flow demonstrates an at least equivalent accuracy concerning the mean flow and provides additional information on the fluctuating fields and shear layers unsteady properties, in fair agreement with the experimental results. Prospects discuss benefits and consequences of this approach taking into account its cost and the industrial context of this application,as well as its potential use for a more complex, installed jet configuration
Gautard-Yzquierdo, Valérie. "Optimisation automatique de formes en aérodynamique application à la conception d'aéronefs." Paris 13, 1999. http://www.theses.fr/1999PA132015.
Full textLambert, Pierre-Alain. "Optimisation de formes en aérodynamique : application à la conception des nacelles de moteurs civils." Châtenay-Malabry, Ecole centrale de Paris, 1995. http://www.theses.fr/1995ECAP0420.
Full textLaurenceau, Julien. "SURFACES DE REPONSE PAR KRIGEAGE POUR L'OPTIMISATION DE FORMES AERODYNAMIQUES." Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2008. http://tel.archives-ouvertes.fr/tel-00339863.
Full textUn nouvel optimiseur basé sur des surfaces de réponse construites par une méthode de Krigeage est proposé. A un surcout modéré, la solution obtenue est meilleure. De plus, cet optimiseur semble aussi capable de traiter des problèmes de grande dimension en interpolant le vecteur gradient aux points de construction du Krigeage.
En optimisation multidisciplinaire, les surfaces de réponse sont largement employées pour échanger facilement des données entre différentes disciplines. Ainsi, une approche d'optimisation bi-niveau avec couplage fluide/structure par surface de réponse est étudiée. L'application considérée traite de l'intégration d'une installation motrice (positionnement) sur un avion de transport civil.
Yousfi, Nabil. "Contribution à l'optimisation aérodynamique des formes des véhicules de tourisme et utilitaires à l'aide des critères d'angles privilégiés entre arêtes." Valenciennes, 2000. https://ged.uphf.fr/nuxeo/site/esupversions/d3a343b6-be81-4c58-a9bf-d13019371942.
Full textRosset, Nicolas. "Simulation rapide d'interactions vent-obstacle. Application à la modélisation de paysages désertiques et à la conception de voiture." Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ4054.
Full textThe air being ubiquitous around us, it is a vital element to take into account to simulate natural phenomena, and design object immersed in this fluid. Depending on their size and nature, objects can be transported, deformed or slowed down by contact with air. In this way, wind erodes and shapes natural landscapes, and vehicles are designed to offer them less resistance. Studying these phenomena involves understanding and modeling wind-obstacle interactions. This is a challenging task, given the non-linear nature of the equations governing fluid flow. Accurately representing fluid behavior often requires the use of time-consuming solvers, which severely limits their use in certain contexts. In this thesis, we explore methods for efficiently describing these wind-obstacle influences in order to simulate them and anticipate their impacts in two use cases where the need for rapid results is crucial: Firstly, we focus on car design, proposing a tool to provide aerodynamic feedback to car designers on the shapes they propose. To enable rapid iterations on the design, this feedback on the flow behavior around the proposed shapes must be interactive. In a second step, we study different approaches to modeling desert landscapes, both simulating dunes and describing the patterns created by sand erosion/deposition around buildings. Here, the obstacle - the terrain - is constantly changing as sand is eroded and deposited by the wind. The wind must in turn be updated at each of these stages. These iterations require an appropriate method to avoid excessive computation times. We overcome these problems by proposing methods that seek the best compromise between computation time and accuracy of the phenomena at work in each case. We identify the necessary flow characteristics to limit the complexity of our algorithms, and present learning-based methods to speed up our algorithms. In the case of car design, we show how to train our aid system on instantaneous, synchronized observations, which are richer in information than averaged data. The neural model we obtain, combined with a learned parameterization of shapes, enables us to invert the problem formulation and propose optimized shapes to the designer. We assemble these tools and demonstrate their effectiveness in the case of 2D profiles.In the case of modeling desert landscapes, we note that saltation is the predominant mode of sand transport, which enables us to simplify our algorithm. Coupled with a fast wind simulation, we obtain an efficient method inspired by both natural sciences and computer graphics. We validate our approximations by comparing our results with real-world measurements.Finally, with a view to inverting the sand deposition algorithm for reverse infrastructure design, we describe preliminary results for accelerating air simulation by developing a self-learning formulation predicting averaged wind over a terrain. As this method is based on neural networks, it shows promise for inverse design
Fol, Thierry. "Optimisation numérique de formes aérodynamiques industrielles." Toulouse 3, 1997. http://www.theses.fr/1997TOU30313.
Full textLaurenceau, Julien. "Surfaces de réponse par krigeage pour l'optimisation de formes aérodynamiques." Phd thesis, Toulouse, INPT, 2008. http://oatao.univ-toulouse.fr/7163/1/laurenceau1.pdf.
Full textBelas, Azzéddine. "Etude et optimisation des formes aérodynamiques des voitures de différentes dimensions." Valenciennes, 2002. https://ged.uphf.fr/nuxeo/site/esupversions/d2872a59-8e62-486f-83c0-bd21bab39185.
Full textThe searches led in our laboratory showed the importance of the privileged angles, notably as regards the reduction of the coefficient of dragged Cx, entailing a decrease of the consumption of the fuel and an improvement of the road holding. Indeed the obtained results confirm the interest of these angles and one observes that the forms of cars built with these angles benefit from a drainage so exempt as possible of the unsticking, and the trail behind the body is stable and little divergent. The purpose thus of this study is to optimize the navy forms, air and ground such as : the veils, the wings planes, the cars and the trains, optimization bound to the stabilitv of the drainage of the fluids around these forms
Rochette, Michel. "Conception optimale de formes appliquée aux résistances ajustables." Nice, 1990. http://www.theses.fr/1990NICE4448.
Full textMasmoudi, Mohamed. "Outils pour la conception optimale de forme." Nice, 1987. http://www.theses.fr/1987NICE4094.
Full textDrullion, Frédérique. "Définition et étude de systèmes linéaires pour la simulation d'écoulements et l'optimisation de formes aérodynamiques par méthode de gradient." Bordeaux 1, 2004. http://www.theses.fr/2004BOR12898.
Full textReineix, Gwenaël. "Conception de sources optoélectroniques transitoires à formes d'ondes maitrisées." Thesis, Limoges, 2020. http://aurore.unilim.fr/theses/nxfile/default/60bc610a-86d7-4b9d-b388-b0ea4256778e/blobholder:0/2020LIMO0011.pdf.
Full textThe work developed in this thesis focuses on two main applications : the generation of signals dedicated to electromagnetic susceptibility tests and the shaping of transient signals applied to spectral shaping for impulse radars. For susceptibility tests, damped sinusoidal signals of a few kilovolts, with frequencies ranging from 20 MHz to 200 MHz, with quality factors between 8 and 12 are considered. In the case of spectral shaping, the generation of several transient signals makes it possible to reproduce an ultrawideband spectrum (300 MHz - 3 GHz) on which frequencies considered undesirable have been rejected.To form the signals useful for these two applications, innovative optoelectronic generators have been developed, the triggering of the signals being controlled by the illumination of photoconductors. The use of photoconductors illuminated by a laser beam generates short pulses (from a few nanoseconds to several hundred nanoseconds) of high voltage (a few kilovolts) with a very low jitter (a few picoseconds).This technique makes it possible to use multiple sources whose signals can be synchronized with each other. A study of the functioning and characterization of photoconductors has been carried out for the optimization of the optoelectronic generators developed. For each application, the designed experimental system is presented
Anani, Victorien. "Formes et formation de l'intelligence : vers une nouvelle conception." Toulouse 2, 1987. http://www.theses.fr/1987TOU20084.
Full textThis exploratory study deals with the issue of the nature of intelligence from a new stand point and proposes a theory based on the use of symbols. French speaking school children from france and west africa experienced auditive and visual stimuli (verbal and schematic statements) of the physical world i. E the world of objects and the psychological world. The study explores the social, cultural and economical determinants of the graphic symbolisation of people namely the ability to understand, to conceive and to rebuilt statements, sequences, in short, forms which use semantic and cognitive structures. Having put forward an applied definition of thinking, the author endeavours to bring out the actual differences between the nature of language (semiotic) and that of thinking (symbolic), between form of content and form of expression, setting them in a cognitive space where "signifier" and "signified" concur. Two separate analyses made it possible to study first, the inter-relationships between the forms of content and expression, then the relationship between these forms and and the variables of the environment. The make up of thinking, the characteristics of which are the symbolic structuring factor, the subjective factor and the theoretical factor, was carried out within a theoretical framework open to techniques of linear regression analysis. The main issue of the relations existing between expression and content, between morphogenesis and structure may find certain elements of solution in this study
Anani, Victorien. "Formes et formation de l'intelligence vers une nouvelle conception /." Lille 3 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376023251.
Full textMasmoudi, Mohamed. "Outils pour la conception optimale de formes environnement d'exploitation /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37607774j.
Full textPicon, Flavien. "Interaction haptique pour la conception de formes en CAO immersive." Phd thesis, Université Paris Sud - Paris XI, 2010. http://tel.archives-ouvertes.fr/tel-00596464.
Full textKassab, Rami. "OPTIMISATION ET CONCEPTION DE FORMES D'ONDE LPI POUR RADAR MONOSTATIQUE." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2009. http://tel.archives-ouvertes.fr/tel-00449768.
Full textDumas, Milne Edwards Léonard. "Conception de formes de relecture dans les chaînes éditoriales numériques." Thesis, Compiègne, 2016. http://www.theses.fr/2016COMP2254/document.
Full textDocumentary production in a professional context often involves a revising process in which documents need to be proofread before validation and publication. This important task faces new challenges when dealing with digital documents. Indeed, three features of digital writing are problematic: documents evolve very frequently and cannot be proofread each time as a whole; interactions provided by hypertexts make the task laborious or even impossible; document repurposing increases the views of content to proofread. As an advanced digital writing technology, XML publishing chains are a relevant framework for studying proofreading of digital documents. Observing that the views of content proposed by publishing chains, namely the generative views (XML sources that can be modified through a WYSIWYM editor) and the published views (documents obtained by transformation of the XML sources), are not adapted for proofreading, we consider designing new views of content dedicated for this activity based on two approaches: linearization, which consists in restoring some material linearity among contents; and tabulation, which aims at parallelizing different repurposing contexts so that they can be better compared. Part of the contribution presented here has led to the development of prototypes that have been experimented in the use of Scenari publishing chains in a pedagogical context. These prototypes rely on linear proofreading views allowing in particular the comparison between two versions of the document based on a diff algorithm
Sander, Agnès. "LES POINTS - DE - RÉSEAUX COMME FORMES URBAINES.Morphogenèse et enjeux de conception." Phd thesis, Université Paris XII Val de Marne, 1995. http://tel.archives-ouvertes.fr/tel-00345093.
Full textMalgré la multiplicité des logiques à l'oeuvre dans la conception des "points-de-réseaux" (logiques d'acteurs diverses à une date donnée, mais aussi logiques successives d'un même acteur dans la durée) et malgré la diversité des sites d'implantation (dont les caractéristiques influent sur la dite conception), des procédés de régulation de la forme et de la fonction de ces points existent.
Ce résultat repose sur deux études empiriques venant compléter un cadre théorique proposé en première partie de la thèse. L'une concerne les points de correspondance entre autobus en région parisienne, l'autre s'intéresse sur la longue durée aux règles mises en oeuvre dans la conception des stations-service. Ces études démontrent en particulier que les procédés régulatoires, au-delà de leur variété (ils sont d'ordre organisationnel ou institutionnel ou de nature architecturale), reposent sur un principe commun de combinaisons d'éléments architecturaux structurants ou évolutifs.
Boboc, Anca. "Formes de socialisation dans la conception automobile : Le cas de Renault." Phd thesis, Ecole des Ponts ParisTech, 2002. http://tel.archives-ouvertes.fr/tel-00005669.
Full textCette thèse s'appuie sur trois ans de recherche de terrain chez Renault, au sein des groupes projet en charge soit du développement du véhicule avant sa commercialisation, soit des évolutions enregistrées par celui-ci après sa commercialisation.
Pour analyser cette dynamique des connaissances dans l'organisation et pour éclairer le processus de conception, en faisant le lien entre ses dimensions individuelles et collectives, nous proposons dans cette thèse un détour par les formes de socialisation que nous entendons comme des modes d'action réciproque.
La modélisation que nous avons construite met en évidence l'existence de trois formes de socialisation - les formes cadrées, les formes moyennement cadrées et les formes non cadrées - en fonction du degré d'intensité de la socialisation entre les acteurs.
Ces formes de socialisation rendent compte de catégories différentes d'interactions qui apparaissent dans des temps et des espaces différents, ainsi que dans des communautés d'acteurs différentes.
Les formes de socialisation nous permettent de parler autant de la coordination et de la coopération que de l'apprentissage. Si nous les regardons par le prisme de l'apprentissage engendré par les interactions entre les acteurs, ces formes de socialisation nous apparaissent comme des formes d'apprentissage. Vues de cette manière, les formes d'apprentissage permettent de mettre en évidence la déviation de la trajectoire du processus d'apprentissage induite par le pouvoir ou par l'arbitrage.
Ces trois formes de socialisation sont interdépendantes et " s'alimentent " réciproquement : chacune d'elles a des limites qui induisent des dysfonctionnements palliés par les deux autres formes.
La manière dont ces trois formes de socialisation s'articulent est essentielle pour comprendre la dynamique des connaissances dans l'organisation, et, par là, les différents problèmes posés aux concepteurs ainsi que les solutions possibles de sortie de l'impasse.
La compréhension de la manière dont ces formes se maintiennent ouvre des voies nouvelles pour la gestion des connaissances dans l'entreprise.
Tortochot, Éric. "Pour une didactique de la conception. Les étudiants en design et les formes d'énonciation de la conception." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM3013.
Full textDesign activity can be analyzed through the signs produced by design developers and their discourse on the new models of artifacts they wished to develop. Psycho-semiotic analysis of student activity in Professional Master of Design shows two processes. First, to solve problems, students report regularly and alone their activities with statements of the different tasks using various representation instruments. Second, to develop different models of artifacts, they falsify the constraints the teachers required with more or less insistence. As students communicate about their work and interact with many people they become aware of their ongoing design activity and organize metaknowledge, values, skills, meaning design abilities. All these acquired abilities are not only based upon the reproduction of conceptual and methodological legacies, routines or habits, but on real inclinations to challenge these legacies using opportunistic strategies. To think about design didactics allows us to understand that students, assisted by teachers, induce themselves a renewal of the design activity. This thesis is an attempt to show that a design didactics, to be formalized, requires taking into account the statement process as an essential cognitive activity for the acquisition of design skills
Goffinet, Marine. "Conception et obtention d'un anticorps spécifique des formes activées des Rho GTPases." Toulouse 3, 2007. http://thesesups.ups-tlse.fr/64/.
Full textThe Rho GTPases A, B and C proteins, members of the Rho family whose activity is regulated by GDP/GTP cycling, function in many cellular pathways controlling proliferation and have recently been implicated in tumorigenesis. Although overexpression of Rho GTPases has been correlated with tumorigenesis, only their GTP-bound forms are able to activate the signalling pathways implicated in tumorigenesis. Thus, the focus of much recent research has been to identify biological tools capable of quantifying the level of cellular GTP-bound Rho, or determining the subcellular location of activation. However useful, these tools used to study the mechanism of Rho activation still have limitations. The aim of the present work was to employ phage display to identify a conformationally-specific single chain fragment variable (scFv) that recognizes the active form of Rho GTPases and is able to discriminate the activated (GTP bound) form of Rho in endogenous settings. After five rounds of phage selection using a constitutively activated mutant of RhoB (RhoBQ63L), three scFvs (A8, C1 and D11) were selected for subsequent analysis. Further biochemical characterization was pursued for the single clone, C1, exhibiting an scFv structure. C1 was selective for the GTP-bound form of RhoA, RhoB, as well as RhoC, and failed to recognize GTP-loaded Rac1 or Cdc42, two other members of the Rho family. Soluble C1 expressed in fusion with the N-terminal of phage protein pIII (scFv C1-N1N2) specifically associated with GTP-loaded recombinant RhoA and RhoB via immunoprecipitation, and endogenous activated Rho in HeLa cells as determined by immunofluorescence. We identified an antibody, C1-N1N2, specific for the GTP-bound form of RhoB from a phage library, and confirmed its specificity towards GTP-bound RhoA and RhoC, as well as RhoB. The success of C1-N1N2 in discriminating activated Rho in immunofluorescence studies implies that this new tool, in collaboration with currently used RhoA and B antibodies, has the potential to analyze Rho activation in cell function and tumor development
Sander, Agnès. "Les "points-de-réseaux" comme formes urbaines : morphogenèse et enjeux de conception." Paris 12, 1995. http://www.theses.fr/1995PA120026.
Full textThe planning of technical networks have more than widely ignored the "network-points", which have often been given a minor place with respect to moving elements (flow, circulation). Those points have nevertheless many different uses : they are functional ways of exit and entrance or connection, places that provide services, public areas and elements that articulate networks and territories. They are essential for the network to operate properly ; they are key elements of the territorial system as well. The network-points's design is submitted to many heterogeneous logics (each actor's rationale is different and doctrines often change). It is also dependant on the diversity of urban settings. Two empirical studies (following a more theoretical approach) brought out that in spite of the difficulties related to this situation, the resulting patterns can be guided and regulated. The first case study deals with bus connection in paris suburbs, the other one explores (from 1905 till now) the rules of gas stations's design and planning. Those case studies also revealed that the regulation (based upon institutional, organisational and architectural means) can be obtained by combining different types of architectural elements, so that some parts of the network-points are allowed to vary while the global shape is preserved
Guillet, Stéphane. "Modification et construction de formes gauches soumises à des contraintes de conception." Grenoble INPG, 1999. http://www.theses.fr/1999INPG0010.
Full textManac'h, Lilia. "Conception et réalisation d'antennes en matériaux composites : intégration dans des plates-formes." Thesis, Rennes 1, 2013. http://www.theses.fr/2013REN1S079.
Full textThe technical and operational requirements of naval, terrestrial and aerial vehicles lead to the design and installation of a great number of antennas for communications. At the same time, composite materials have been used for many decades in structural panels of vehicles for their intrinsic qualities (lightness, high mechanical performance, insensitivity to corrosion ...). The purpose of this manuscript is the study and engineering of composite materials for antenna applications at microwaves. After an exhaustive survey of the dielectric characteristics of the various elements of composite materials, dielectric characterization of composite materials manufactured in the Laboratory was carried out using two different methods in two different frequency bands. Meanwhile, an analysis of their conductive characteristics allows carbon-fiber tissues to be used in the design of radiating elements. First, two "full-composite" square shaped antennas based on carbon-fiber tissues, glass-fiber tissues and polyester or epoxy resin have been developed, fabricated and measured. Their performance, similar to that of reference metal antennas demonstrates their relevance for microwave applications. Then, three different topologies of ultra wideband "full-composite" antennas have been specifically developed for the SAMCOM (/Antenna Systems in COMposite Materials)/ FUI project. The first, a Rugby-Ball shaped antenna, has one octave and a half of bandwidth with a positive gain and λ/4 x λ/4 x λ/10 dimensions (length x width x height). The second, a 3D dipole antenna with λ/3 x λ/3 x λ/10 dimensions, has two octaves and a half of bandwidth also with a positive gain. At last, the third antenna with a planar structure has been specifically developed for the reception of digital terrestrial television (DTT) and will be, at the end, integrated into a structural panel of a terrestrial vehicle
Guillaume, Philippe. "Dérivées d'ordre supérieur en conception optimale de forme." Toulouse 3, 1994. http://www.theses.fr/1994TOU30041.
Full textGagné, Christian. "Algorithmes évolutionnaires appliqués à la reconnaissance des formes et à la conception optique." Thesis, Université Laval, 2005. http://www.theses.ulaval.ca/2005/22701/22701.pdf.
Full textEvolutionary Algorithms (EA) encompass a family of robust search algorithms loosely inspired by natural evolution. These algorithms are particularly useful to solve problems for which classical algorithms of optimization, learning, or automatic design cannot produce good results. In this thesis, we propose a common methodological approach for the development of EA-based intelligent systems. This methodological approach is based on five principles : 1) to use algorithms and representations that are problem specific ; 2) to develop hybrids between EA and heuristics from the application field ; 3) to take advantage of multi-objective evolutionary optimization ; 4) to do co-evolution for the simultaneous resolution of several sub-problems of a common application and for promoting robustness ; and 5) to use generic software tools for rapid development of unconventional EA. This methodological approach is illustrated on four applications of EA to hard problems. Moreover, the fifth principle is explained in the study on genericity of EA software tools. The application of EA to complex problems requires the use of generic software tool, for which we propose six genericity criteria. Many EA software tools are available in the community, but only a few are really generic. Indeed, an evaluation of some popular tools tells us that only three respect all these criteria, of which the framework Open BEAGLE, developed during the Ph.D. Open BEAGLE is organized into three main software layers. The basic layer is made of the object oriented foundations, over which there is the generic framework layer, consisting of the general mechanisms of the tool, and then the final layer, containing several specialized frameworks implementing different EA flavors. The tool also includes two extensions, respectively to distribute the computations over many computers and to visualize results. Three applications illustrate different approaches for using EA in the context of pattern recognition. First, nearest neighbor classifiers are optimized, with the prototype selection using a genetic algorithm simultaneously to the Genetic Programming (GP) of neighborhood metrics. We add to this cooperative two species co-evolution a third coevolving competitive species for selecting test data in order to improve the generalization capability of solutions. A second application consists in designing representations with GP for handwritten character recognition. This evolutionary engineering is conducted with an automatic positioning of regions in a window of attention, combined with the selection of fuzzy sets for feature extraction. This application is used to automate character representation search, which is usually conducted by human experts with a trial and error process. For the third application in pattern recognition, we propose an extensible system for the hierarchical combination of classifiers into a fuzzy decision tree. In this system, the tree topology is evolved with GP while the numerical parameters of classification units are determined by specialized learning techniques. The system is tested with three simple types of classification units. All of these applications in pattern recognition have been implemented using a two-objective fitness measure in order to minimize classification errors and solutions complexity. The last application demonstrate the efficiency of EA for lens system design. Selfadaptative evolution strategies, hybridized with a specialized local optimisation technique, are used to solve two complex optical design problems. In both cases, the experiments demonstrate that hybridized EA are able to produce results that are comparable or better than those obtained by human experts. These results are encouraging from the standpoint of a fully automated optical design process. An additional experiment is also conducted with a two-objectives fitness measure that tries to maximize image quality while minimizing lens system cost.
Seguy, Nicolas. "Modélisation modulaire de systèmes articulés : Conception orientée-objet de plates-formes de simulation." Evry-Val d'Essonne, 2003. http://www.theses.fr/2003EVRY0014.
Full textThis work presents a modular model of rigid multibody systems using penalty methods in the context of interactive simulation in computer-aided design. A dynamic system can be viewed as an assembly of constrained sub-systems with their own formalism and solving methods. Automatic calculation of penalty factors at each joint and the use of an iterative process based on an augmented Lagrangian formulation in components insure numerical stability. Formalisms and solving methods are chosen for flexibility in order to easily modify the topology of the system. This assembly of autonomous components is well suited to object-oriented programming in which instances of the basic classes can dynamically be added or removed. The simulation tool can then interactively modify the virtual scene
Beux, François. "Conception optimale de formes aerodynamiques et methodes d'approximations decentrees pour des ecoulements incompressibles." Nice, 1993. http://www.theses.fr/1993NICE4636.
Full textGrosjean, Sylvain. "Conception de plates-formes moléculaires hétérocycliques : application à la synthèse d'analogues de nucléosides." Nantes, 2010. http://archive.bu.univ-nantes.fr/pollux/show.action?id=08af25e8-eef1-48d7-aa05-fc71cf118eb8.
Full textThe purpose of this work is a methodological study in heterocyclic chemistry, aiming at the synthesis of nitrogen bicyclic compounds. Chapter 1 deals with the synthesis of sulfur and nitrogen heterodienic chains and their use in [4+2] heterocyclization reactions for the synthesis of carbonylated and thiocarbonylated methylsulfanylpyrimidines. Chapter 2 describes the structural modifications which were brought to pyrimidine rings in order to perform the second ring construction. The key-step of the strategy is the nucleophilic displacement of the methylsulfanyl group on the pyrimidine ring. The synthesis leads to the formation of 1,3,7-trisubstituted pyrimido[1,2-a]pyrimidines. Chapter 3 is an application of the described methodological approach. It outlines the synthesis of puric base nucleoside analogues from glycosylisothiocyanates
Meyrueis, Vincent. "Modification interactive de formes en réalité virtuelle : application à la conception d'un produit." Phd thesis, Paris, ENMP, 2011. https://pastel.hal.science/pastel-00609563.
Full textThe context of this research is the use of virtual reality for product design and development. At the industrial level, the virtual integration reviews are currently limited to static project review, with no possibility of changing the original design. In this work, we present a new method for virtual design review, which aims to enable the user to modify, as naturally as possible, the digital model inside the virtual environment. This method, called D3, is based on three steps: a selection step by drawing, a deformation step by manipulating the selected area and a final refining step that allows engineers to adjust the modifications. For the method to be a means of communication, it has to be simple, intuitive and usable by all project actors. An experiment was performed to evaluate the method in terms of learning curve and errors performed by subjects in a modification task. Finally, in order to facilitate the refining step, this method offers several ways for engineers to reflect the modifications on the CAD model
Meyrueis, Vincent. "Modification interactive de formes en réalité virtuelle : application à la conception d'un produit." Phd thesis, École Nationale Supérieure des Mines de Paris, 2011. http://pastel.archives-ouvertes.fr/pastel-00609563.
Full textSilvestri, Chiara. "Perception et conception en architecture non standard : une approche expérimentale pour l'étude des processus de conception spatiale des formes complexes." Phd thesis, Montpellier 2, 2009. http://www.theses.fr/2009MON20144.
Full textDesign processes rely on the interaction between virtual space of possibility and real space of constructability: this interaction is performed and managed in the designer's mental space. In contemporary Non Standard architecture formal complexity and digital tools are creating a growing gap between virtual space (possibility) and real space (constructability). Our these's aim is to contribute at the understanding of the position of designer's mental space face to this gap. One of our objectives was the definition of a scientific reference frame for the experimental study of the relationships between the designer's mental space and the world's physical space. Cognitive sciences provided the methodology and tools necessary to perform a scientific study of those questions. Two experiments were conduced to identify geometrical invariants and laws which could relate the formal qualities of physical space objects and the correspondent mental space representations. Our results revealed significant data about the perceptual elaboration of the formal qualities of curvature and of complex spatial configurations, in relation with different representation tools (physical scale models, numerical models, drawings)
Silvestri, Chiara. "Perception et conception en architecture non standard : une approche expérimentale pour l'étude des processus de conception spatiale des formes complexes." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2009. http://tel.archives-ouvertes.fr/tel-00858782.
Full textMoinereau, Dominique. "Conception d'un microsystème d'analyse d'images appliqué au comptage de formes convexes à tendance circulaire." Dijon, 1989. http://www.theses.fr/1989DIJOS023.
Full textMostefai, Mohammed. "Un modèle d'architecture orienté objet pour la conception de plate-formes de simulation interactive." Lille 1, 1994. http://www.theses.fr/1994LIL10057.
Full textIngrand, Félix. "Inférence de formes à partir de fonctions : application à la conception de montage d'usinage." Grenoble INPG, 1987. http://www.theses.fr/1987INPG0013.
Full textIngrand, François. "Inférence de formes à partir de fonctions application à la conception de montage d'usinage /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37606056f.
Full textHisarciklilar, Onur. "Formes et structures des annotations sémantiques pour supporter la communication en conception collaborative asynchrone." Phd thesis, Grenoble INPG, 2008. http://www.theses.fr/2008INPG0130.
Full textToday's collaborative design processes are characterized by an increasing number of co-operative situations, where geographically distributed participants from different domains of expertise are required to build mutual understanding of the ongoing design context, in order to collectively evaluate design solutions. 3D product representations are often used in these situations as common artefacts between the participants. In spite of the current CSCW technologies, asynchronous communication with 3D representations remains difficult. This is due to the lack of functionalities that allow the participants expressing the tacit design information on the 3D models and of mechanisms that support the participants to realise argumentative communication. The main problem addressed in this work is how the annotations can be used in 3D representations to support asynchronous design communication, in order to allow the design participants sharing and debating design information more systematically. The outcomes of this work include (1) an annotation model, allowing participants to express their design intent along with information conveyed, (2) an annotation structure, facilitating the accurate interpretation of information by unifying communicative and informational dimensions of the annotation content, (3) an annotation repository to improve annotation retrieval and re-use, (4) the Annot'Action environment as an implementation of the proposed concepts
Hisarciklilar, Onur. "Formes et structures des annotations sémantiques pour supporter la communication en conception collaborative asynchrone." Phd thesis, Grenoble INPG, 2008. http://tel.archives-ouvertes.fr/tel-00419297.
Full textCauchois, Olivier. "Conception, Préparation & Caractérisation de Nanoparticules de Formes Complexes. Etude de leur Devenir In Vivo." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00659379.
Full textTournier, Christophe. "Contribution à la conception des formes complexes : la surface d'usinage en fraisage 5 axes isocrête." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2001. http://tel.archives-ouvertes.fr/tel-00366649.
Full textBel, Habib Basma. "Méthodologie pour le développement de plates formes intégrées dédiées à la conception en génie électrique." Grenoble INPG, 2000. http://www.theses.fr/2000INPG0049.
Full textThis work deals with the development of environments dedicated to electrical design. The first target of our project is to define a methodology to support interaction between several individual design software. First a synthesis of the design activity'and a state of the art of available tools dedicated to electrical products design are made. It has been shown that there is a real need of a computer environment providing software links and reusable design process. To address this problem, we introduce the concept of Electrical Design Integrated Platform. We propose a way of coupling heterogeneous tools and transferring parameters. To implement this architecture, the JAVA_abject Server model has been carried thanks to the encapsulation of the design tools in Components. Finally, the developed prototype of Electrical Design Integrated Platform is detailed
Dagher, Antoine. "Contribution à l'intégration des préférences client en conception de produits : application au design des formes." Nantes, 2008. http://www.theses.fr/2008NANT2089.
Full textIn today’s highly competitive market, developing new products that satisfy consumers’ needs is a very important issue. A successful product must satisfy consumers’ requirements. Emotional and aesthetics factors are also very important points for the purchase decision. Perceptual aspects of products dominate the technical specifications. In this report, we are interested in the impact of geometrical forms on users’ preference. The general problem consists of studying the possibility of designing geometrical forms while taking into account user’s preference. Two applications are proposed in order to illustrate the proposed methods: The first in automotive industry and another in the design of hand watches. A brief state of the art was first carried out on user centered design methods. A comparative procedure is then proposed for the definition of design attributes of a product with respect to its perceptions. Next, we studied the relevance of the conjoint analysis models to establish a relation between users’ preferences and design attributes. We compared two methods for preference scores collection: Direct rating and paired comparisons; and two conjoint analysis models (Rating based and Choice based) used for preference modeling. Lastly, we propose a new methodology for preference mapping allowing the link between user preference and the design variables. The multidimensional scaling is used to define perceptive dimensions that will be explained by perceptive metrics. Linear regression is used to build a model for the synthesis of forms with optimal preference. The cars headlight design application presents the key points and the limits of such models in industrial design
Turbatte, Hervé-Claude. "Conception d'architectures d'instrumentation sous contraintes d'observabilité et de fiabilité : application à des plates-formes pétrolières." Vandoeuvre-les-Nancy, INPL, 1992. http://www.theses.fr/1992INPL087N.
Full textFor a given process, our aim is on the one hand to assess the availability of the necessary informations for the process control, and on the other hand to define the sensor location in order that the necessary variables for control are al ways observable when one or more sensors are defective subject to reliability,location and cost constraints. Two approaches to estimate the reliability of a measurement system are presented. In the first, the reliability is simply calculated by searching the sensory breakdown configurations for which. The system remains observable. Ln the second; we calculate the unrelizbility function using Fault Tree Method. To search the most reliable measurement system, four methods are presented. These methods are based on the MTIF comparison among different measurement systems, or on the structural analysis of the process graph, or on the analysis of the reliability evaluation vs time or more on the cycles study of the process graph. The proposed methods are successfully applied to an off-shore platform of the French petroleum company Elf Aquitaine
Tan, Uy Hour. "Méthodologies de conception de formes d'onde pour radars sol. Application au cas du radar MIMO." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLC036/document.
Full textThis thesis deals with coherent MIMO radars. MIMO stands for Multiple-Input Multiple-Output, meaning that several transmitters and several receivers are used, closely-spaced in a coherent MIMO radar. Each transmitter has its own signal, providing waveform diversity. This thesis aims for defining a way to generate a set of sequences, specific for this radar, while satisfying practical constraints. It may help to determine the potential contribution of a MIMO radar. Only phase codes are concerned here, because they suffer less from the range/angle coupling effect.A simple framework is introduced, based on an optimisation problem.While literature often involves the orthogonality of the elementary signals (because of theoretical aspects), it is suggested to consider the orthogonality of signals from different directions of the surveillance space. Unfortunately, the obtained optimisation problem is non-convex and has a lot of variables. A benchmark on a simpler problem notifies us that gradient-based algorithms are surprisingly efficient.An optimisation of the correlation function corresponds to a processing with matched filters. However, in practice, mismatched filters are usually employed. A joint optimisation problem is suggested accordingly, in order to generate simultaneously a set of sequences (e.g. MIMO radar signals) and their associated mismatched filters. Obtained results are quite promising : as expected, a joint optimisation seems to perform better than a cyclic one, usually employed
Jolion, Jean-Michel. "Méthodologie de conception de systèmes d'analyse d'images : application à la microscopie électronique." Lyon, INSA, 1987. http://www.theses.fr/1987ISAL0003.
Full textKinvi-Boh, Ékué. "Conception de circuits en logique ternaire : de la caractérisation au niveau transistor à la modélisation architecturale." Rennes 1, 2006. http://www.theses.fr/2006REN1S077.
Full text