Дисертації з теми "Contraintes spatiales et géométriques"
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Léoty, Florent. "Vers le couplage sémantique de planifications de tâches et de trajectoires pour la validation de tâches complexes sous fortes contraintes spatiales." Electronic Thesis or Diss., Toulouse, INPT, 2023. http://www.theses.fr/2023INPT0135.
To remain competitive, manufacturers need to reduce the costs and development times of their new products. Current products are increasingly integrated, smaller, lighter and more energyefficient. They are more difficult to design and have to be assembled, maintained and disassembled under very high geometric constraints. Traditionally, during the design phase, the CAD model of the product is established, then the physical parts of the product are manufactured, to discover all too often that some or all of the tasks associated with the product's life cycle are difficult or impossible to carry out. If these problems are detected too late, the product design has to be reconsidered. The aim of this thesis is to validate, at the design stage, all the tasks associated to the PLM using digital simulation before the physical prototypes are manufactured. This would make it possible to reduce development times and costs and to aim for more environmentally-friendly manufacturing processes by reducing the number of physical prototypes manufactured. A key step in the simulation-based validation of PLM tasks is to find a feasible collision-free trajectory in order to prove their feasibility. Since the 1980s, the robotics community has been using automatic path planning methods to solve this problem. However, these methods have limitations, mainly linked to the complexity of the environment models, which are traditionally purely geometric. In very complex environments, path planners can propose trajectories that are not very relevant, in times that can be very long, or even fail. To overcome these limitations, some works has considered collaborative human-planner approaches, but these rarely enable continuous interaction. On the other hand, VR techniques allow simulation with a human operator in the loop, immersed in the virtual environment and interacting with it. An original approach linking automatic path planning and VR has been developed at LGP, taking advantage of the computing power of computers and the cognitive abilities of a human operator. However, in this approach, the assistance offered to the operator is not oriented towards the task to be carried out. In order to be able to reason at the level of the task to be carried out, task planning and path planning must be considered together, and attention must be paid to the ability to model information relating to the task and to reason about these information; ontologies are a promising tool. The aim of this thesis is to develop a common framework for the semantic coupling of path and task planners for manipulation assistance in VR or robotics. Within this framework, we propose two main contributions: The first contribution of this work proposes two original ontologies. The first, ENVOn-2, concerns the modelling of the environment in which a manipulation task takes place. The second, TAMPO, is an ontology developed for jointly use path and task planning. The second contribution concerns the development of a methodology for the semantic coupling of task and trajectory planners. This methodology, through the joint use of the two ontologies, makes it possible to improve the path planning of a primitive action while proposing a task plan (or plans) that is (are) relevant to the manipulation being carried out. These developments were then validated using a variety of scenarios of increasing complexity. The results obtained demonstrate the relevance of the approach
Jabeur, Mohamed. "Méthodes géométriques en mécanique spatiale et aspects numériques." Dijon, 2004. http://www.theses.fr/2005DIJOS002.
Le, Guyader Carole. "Imagerie mathématique : segmentation sous contraintes géométriques : théorie et applications." Phd thesis, Rouen, INSA, 2004. http://www.theses.fr/2004ISAM0016.
Le, Guyader Carole. "Imagerie Mathématique: segmentation sous contraintes géométriques ~ Théorie et Applications." Phd thesis, INSA de Rouen, 2004. http://tel.archives-ouvertes.fr/tel-00009036.
Pour pallier ces difficultés, nous proposons ici des modèles de segmentation intégrant des contraintes géométriques et satisfaisant les critères classiques de détection avec en particulier la régularité sur le contour que cela implique.
Jermann, Christophe. "Résolution de contraintes géométriques par rigidification récursive et propagation d'intervalles." Nice, 2002. http://www.theses.fr/2002NICE5766.
Geometric constraint satisfaction problems (GCSPs) are ubiquitous in applications like CAD, robotics or molecular biology. They consist in searching positions, orientations and dimensions of geometric objects bound by geometric constraints. The goal of the thesis was to find an efficient and complete solving method for GCSPs. In the first part, we compare solving methods and decomposition techniques, and we choose Hoffmann et al's decomposition and interval solving methods. We define a general framework for the study of rigidity in GCSPs, a concept used in all the geometric decomposition methods. In the second part, we analyse Hoffmann et al's method, and the limits inherent to all the structural geometric approaches. We propose the degree of rigidity concept to overcome some of these limits. We introduce a new decomposition method, and its combination with interval solving methods
Radvanyi, Jean. "Régions et pouvoirs en U.R.S.S. contraintes spatiales et politique régionale." Lille 3 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb375951058.
Jermann, Christophe. "Résolution de contraintes géométriques par rigidifications récursive et propagation d'intervalles." Phd thesis, Université de Nice Sophia-Antipolis, 2002. http://tel.archives-ouvertes.fr/tel-00505433.
Chupeau, Marie. "Différentes propriétés de marches aléatoires avec contraintes géométriques et dynamiques." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066167/document.
We first determine the impact of an infinite reflecting wall on the space occupied by a planar Brownian motion at a fixed observation time. We characterize it by the mean perimeter of its convex hull, defined as the minimal convex polygon enclosing the whole trajectory. We also determine the mean length of the visited portion of the wall, and the survival probability of a Brownian walker in an absorbing wedge.We then study the time needed for a lattice random walker to visit every site of a confined volume, or a fraction of them. We calculate the mean value of this so-called cover time in one dimension for a persistant random walk. We also determine the distribution of the cover time and related observables for the class of non compact processes, which describes a wide range of random searches.After that, we calculate and analyze the splitting probability of a one-dimensional Brownian walker evolving in an expanding or contracting interval.Last, we study several aspects of the model of starving random walk, where the walker starves if its visits to new sites, from which it collects resources, are not regular enough. We develop a mean-field treatment of this model in two dimensions, then determine the impact of regeneration of resources on the survival properties of the walker. We finally consider a model of exploitation of food patches taking explicitly into account the displacement of the walker in the patches, which can be mapped onto the starving random walk model
Thomas-Moinet, Mireille. "Descriptions non cartésiennes et résolution de problèmes géométriques sous contraintes." Châtenay-Malabry, Ecole centrale de Paris, 2008. http://www.theses.fr/2008ECAP1100.
This thesis an effective method to describe and solve in a declarative way geometrical problems defined by constraints. This method of description is omnipresent in CAD to define the shape of objects. To do it, we relied on works already realized in this domain, especially using non-Cartesian approaches. The first chapter makes the synthesis of the state of the art in declarative modelling of a geometric object. The second chapter deals with the chosen modelling : a non-cartesian approach based on a certain metric tensor perturbation. A format equation and an original resolution method are detailed as well as the algorithms implemented. Numerical examples illustrate the performance of the prototype developed. The third chapter proposes to enrich the previous approach using multivectors. New specifications for the user are available and in return, new types of equations must be a generated. Numerical applications of this multi-vectoriel modelling are done. Finally, in the last chapter, it is proposed to extend the tensor model to a model based on geometric algebra. This new tool and a solution allowing to represent objects and constraints with this language, are presented
Ménegaux, David. "Modélisation de courbes et de surfaces algébriques par contraintes géométriques." Dijon, 2006. http://www.theses.fr/2006DIJOS037.
Curves and surfaces modelling is an essential step in the process of designing complex objects. Among the various existing models, we are here interested in the implicit curves and surfaces, i. E. Whose equation is polynomial. The aim of this study is first to solve a set of geometric constraints and find an implicit curve/surface which fits best those constraints: comparisons are made when using different basis to define the functions (such as canonical, radial, or Bernstein-based functions). The second step is about how to compute and plot the curve/surface: a classical subdivision method is used including interval arithmetic, and improved with a method inspired by Bézier, Bernstein and de Casteljau's works. An extension to this method uses the Taylor expansion, allowing transcendent functions to be computed and plotted as well
Thierry, Simon Emile Bernard. "Décomposition et paramétrisation de systèmes de contraintes géométriques sous-contraint." Strasbourg, 2010. http://www.theses.fr/2010STRA6114.
Solving geometric constraint systems (GCS) aims at yielding figures which respect geometric requirements given by the user under the form of a technical sketch. The GCS given by the user can be wellconstrained (it describes a nonzero finite number of figures), underconstrained (an infinity of figures) or overconstrained (no solutions at all). Classically, underconstrained systems are considered as errors to be corrected by the user. Our work proposes another approach, i. E. Try to homogeneously solve all nonoverconstrained systems. For that, we propose parameterization algorithms: they indicate which elements of the system need to be anchored for there to be a finite number of solutions~; and decomposition algorithms, which allow to identify wellconstrained subsystems. These tools open the way to constraintbased modelers which are accessible to nonexpert users: they give intuitive visual feedback about the constrainedness level of the system. Since our algorithms are all incremental, they allow a trial and error approach: the user corrects the sketch as the resolution goes
CAMBON, Stephane. "Planifier avec les contraintes géométriques du mouvement et de la manipulation." Phd thesis, Université Paul Sabatier - Toulouse III, 2005. http://tel.archives-ouvertes.fr/tel-00009845.
Cambon, Stéphane. "Planifier avec les contraintes géométriques du mouvement et de la manipulation." Toulouse 3, 2005. http://www.theses.fr/2005TOU30060.
One of the goal of researches in task planning is to elaborate models and algorithms that contribute to the robots autonomy by giving them decisional abilities. Classically, a symbolic plan computed by a planner let the robot take the decisions of the next actions it must fulfill to satisfy its mission. In this thesis, we develop the following idea: current planners, based on a logical representation of the world, are not able to deal with missions where robots motions constraints and objects manipulation constraints cannot be ignored at this step. In Robotic, the feasibility of motion and manipulation is often a precondition to the good execution of a plan. In this thesis we introduce a formalism that allows us take into account these constraints in the model used by a planner. By using results from motion and manipulation planning as much as some from task planning, we propose a new planner able to reason on this formalism. We produce plans that define not only an order of action but also the motions without collision needed for its execution. The planner implementation is presented and evaluated
Duong, An-Ninh. "Spécification, analyse, et résolution des problèmes géométriques 2D et 3D modélisés par contraintes." Châtenay-Malabry, Ecole centrale de Paris, 2003. http://www.theses.fr/2003ECAP0930.
Radvanyi, Jean. "Régions et pouvoirs en URSS : contraintes spatiales et politique régionale en URSS." Paris 7, 1985. http://www.theses.fr/1985PA070108.
Rose, Jean-Loïc. "Croissance de région variationnelle et contraintes géométriques tridimensionnelles pour la segmentation d'image." Lyon, INSA, 2008. http://theses.insa-lyon.fr/publication/2008ISAL0108/these.pdf.
IMAGE segmentation through region growing is a method that localizes and extracts an object from an image. When difficult segmentation context are linked to noise or a lack of information, the use of prior knowledge in the region growing process improves segmentation accuracy. Medical imaging is often concerned by this context. Moreover, medical applications deal with large amounts of data. Then, it is mandatory to use a robust and fast processing. This context leads us to propose a shape prior for the region growing process. The manuscript presents our work composed of two main contributions. Firstly, we proposed to define region growing in the variational framework. We choose to describe our region by a discrete function. The region evolution equation is defined in a variational formulation. An energy functional minimization is associated with our function. For the criterion minimum, the segmented region describes the desired object. The main interest of our region growing approach is the use of region based energy minimization in the evolution process. Then, we define a region-based shape constrain in the segmentation. We define shape descriptors based on Tchebychev moments. We proposed to introduce a weighting term into our functional. This term allows to consider the Tchebychev moments hierarchy, thus adapting our criterion with the encoded moments information. We have proposed a shape prior which incorporates invariance with respect to the group of similarity transformations of a given shape. Our shape constrain is defined for two-dimensional and three-dimensional images. We apply our shape prior in the variational region growing. This application shows the ability of our method to incorporate region-based energy. We propose to study the ability of our shape constrain to influence the evolution of the region growing near the desired shape. Segmentation results are given for synthetic and real images. IMAGE segmentation through region growing is a method that localizes and extracts an object from an image. When difficult segmentation context are linked to noise or a lack of information, the use of prior knowledge in the region growing process improves segmentation accuracy. Medical imaging is often concerned by this context. Moreover, medical applications deal with large amounts of data. Then, it is mandatory to use a robust and fast processing. This context leads us to propose a shape prior for the region growing process. The manuscript presents our work composed of two main contributions. Firstly, we proposed to define region growing in the variational framework. We choose to describe our region by a discrete function. The region evolution equation is defined in a variational formulation. An energy functional minimization is associated with our function. For the criterion minimum, the segmented region describes the desired object. The main interest of our region growing approach is the use of region based energy minimization in the evolution process. Then, we define a region-based shape constrain in the segmentation. We define shape descriptors based on Tchebychev moments. We proposed to introduce a weighting term into our functional. This term allows to consider the Tchebychev moments hierarchy, thus adapting our criterion with the encoded moments information. We have proposed a shape prior which incorporates invariance with respect to the group of similarity transformations of a given shape. Our shape constrain is defined for two-dimensional and three-dimensional images. We apply our shape prior in the variational region growing. This application shows the ability of our method to incorporate region-based energy. We propose to study the ability of our shape constrain to influence the evolution of the region growing near the desired shape. Segmentation results are given for synthetic and real images
Carrère, Frédéric. "Optimisation de formes en aérodynamique hypersonique avec contraintes géométriques et furtivité électromagnétique." Bordeaux 1, 1994. http://www.theses.fr/1994BOR10637.
Zhao, Ting. "Résolution de systèmes polynomiaux paramétriques par radicaux et ses applications géométriques." Paris 6, 2012. http://www.theses.fr/2012PA066131.
Aldowaji, Alali Marwa. "Stabilité et dynamique des systèmes non conservatifs, aspects géométriques." Thesis, Evry-Val d'Essonne, 2014. http://www.theses.fr/2014EVRY0018.
This paper investigates the linear static stability of constrained nonconservative mechanical systems. More precisely, the systems studied are elastic systems subjected to nonconservative positional forces. It is also well known that such systems may present paradoxical behaviors,. It is, however, less reported that other paradoxical effects may be met for additional constraints. The additional constraint may destabilize the system and preventing the instability by divergence of the constrained system (ie for any kinematic constraint) leads to the second order work criterion (CTSO). The CTSO and the problematic of additional constraints remain the principle of our work. Furthermore, the results obtained (p-positive definite matrices, The geometric degree of nonconservativity,….). THE CTSO AND additional KINEMATIC constraints, THUS LEAVING MANY THEMES FOR FUTURE RESEARCH
Bishani, Leila. "Méthodologie de conception et intégration de contraintes géométriques en conception mécanique assistée par ordinateur." Lyon, INSA, 1998. http://www.theses.fr/1998ISAL0111.
Actually Mechanical design use a computer Aided to optimise the time, the cost and performance of product for manufacturing. This study treats the problem of Mechanical design in general, but based on a concrete case already studied. The bibliography shows that indeed a space enough separates the general ideas of theoretical of the concrete aspects of the mechanical design. More particularly, four design projects of power transmission by Gear or bet has been considered. Projects have been developed in the environment CATIA, the conditions and the behaviour has been also extracted. The third part of this thesis is consisted to extrapolate the result and the method acquired to an industrial case of drilling moult-head gear box/design. Always in CATIA environrnent, many solutions have been proposed by repressing a large number of geometrical conditions. In summary, the observation and the realisation of significant mechanical cases have allowed to reduce the distance a between the application and the theory. The treated cases have been presented in order to that could serve also in the framework of the Primeca
Laborde, Olivier. "Formes quadratiques, géométrie affine et méthodes géométriques en géologie." Montpellier 2, 1989. http://www.theses.fr/1989MON20015.
Draréni, Jamil. "Exploitation de contraintes photométriques et géométriques en vision : application au suivi, au calibrage et à la reconstruction." Grenoble, 2010. http://www.theses.fr/2010GRENM061.
The topic of this thesis revolves around three fundamental problems in computer vision; namely, video tracking, camera calibration and shape recovery. The proposed methods are solely based on photometric and geometric constraints found in the images. Video tracking, usually performed on a video sequence, consists in tracking a region of interest, selected manually by an operator. We extend a successful tracking method by adding the ability to estimate the orientation of the tracked object. Furthermore, we consider another fundamental problem in computer vision: calibration. Here we tackle the problem of calibrating linear cameras (a. K. A: pushbroom)and video projectors. For the former one we propose a convenient plane-based calibration algorithm and for the latter, a calibration algorithm that does not require aphysical grid and a planar auto-calibration algorithm. Finally, we pointed our third research direction toward shape reconstruction using coplanar shadows. This technique is known to suffer from a bas-relief ambiguity if no extra information on the scene or light source is provided. We propose a simple method to reduce this ambiguity from four to a single parameter. We achieve this by taking into account the visibility of the light spots in the camera
Diedrich, Florian. "Algorithmes d'approximation pour des programmes linéaires et les problèmes de packing avec des contraintes géométriques." Grenoble INPG, 2009. http://www.theses.fr/2009INPG0014.
In this thesis we approach several problems with approximation algorithms ; these are feasibility problems as well as optimization problems
Mazon, Isabelle. "Raisonnement sur les contraintes géométriques et d'incertitudes pour la planification de tâches de manipulation robotisées." Toulouse 3, 1990. http://www.theses.fr/1990TOU30131.
Duboisset, Magali. "Un système de contraintes d'intégrité OCL pour les bases de données spatiales." Phd thesis, Clermont-Ferrand 2, 2007. http://www.theses.fr/2007CLF21797.
Salesse, Robin. "La dynamique des coordinations inter-segmentaires, résultat d'une coalition des contraintes neuromusculaires et spatiales." Phd thesis, Université de la Méditerranée - Aix-Marseille II, 2006. http://tel.archives-ouvertes.fr/tel-00126502.
Plus particulièrement il s'intéresse aux conditions dans lesquelles ces contraintes influencent
la production des patrons de coordination. Plus spécifiquement, nous avons étudié (1) la nature
de l'interaction entre les contraintes neuromusculaires et directionnelles en fonction du
plan de mouvement dans lequel les tâches sont réalisées et (2) le support perceptif de la
contrainte directionnelle.
Nous avons analysé la stabilité (nombre de transitions de phase, temps avant transition,
variabilité de la phase relative) et la précision (erreur absolue de la phase relative) des
coordinations.
La manipulation systématique et différenciée des contraintes neuromusculaires et directionnelles
a montré qu'indépendamment du type de coordination réalisé, la contrainte directionnelle
jouait un rôle dominant sur la dynamique des coordinations inter-segmentaires.
En effet, quel que soit le plan de mouvement, les mouvements symétriques par rapport au plan
sagittal médian du corps sont toujours les plus stables et les plus précis. Toutefois, la
contrainte neuromusculaire joue également un rôle dans cette dynamique mais de moindre
importance. La manipulation de la perception visuelle du déplacement des membres a montré
que le principe d'isodirectionnalité perceptive dépendait des conditions dans lesquelles les
tâches sont réalisées (plan de mouvement et couplages neuromusculaires).
L'ensemble de ce travail de thèse suggère que la dynamique des coordinations motrices
résulte de l'assemblage complexe en coopération ou en compétition des contraintes relatives
au degré de symétrie des coordinations, aux couplages musculaires impliqués dans le
mouvement et aux plans de mouvement dans lequel les tâches sont réalisées.
Salesse, Robin. "La dynamique des coordinations inter-segmentaires : résultats d'une coalition des contraintes neuromusculaires et spatiales." Aix-Marseille 2, 2006. http://theses.univ-amu.fr.lama.univ-amu.fr/2006AIX22055.pdf.
This Thesis presents the results of five experiments carried out to investigate the role of neuromuscular constraints, spatial constraints, visual feedback and plane of motion, on interlimb coordination dynamics (bimanual, hand-foot, handheld pendulum). In particular, we investigated the conditions under which these constraints influence pattern stability and changes. Specifically, we assessed (1) the nature of the interaction between neuromuscular and directional constraints as a function of the plane of motion of the task are performed and (2) the role of visual perception as a support of the directional constraint. Pattern stability (phase transitions, time to transition, and relative phase variability) and accuracy of performance (absolute error of the relative phase) were analyzed. Results show that whatever the experimental task context, directional constraints play a dominant role in interlimb coordination dynamics. Indeed, symmetrical movements with respect to the sagittal plane of the body exhibit the most stable and accurate patterns of coordination, irrespective of the plane of motion in which the tasks are performed. However, neuromuscular constraints also play a secondary role. Manipulation of the visual information about the relative direction of movement shows that a “perceptual isodirectional principle” is at work during the production of interlimb coordination. However, the influence of this principle depends on the conditions in which the tasks are performed (plane of motion, neuromuscular coupling). To sum up, the present work suggests that interlimb coordination dynamics is a result of complex interaction, in cooperation or in competition, between constraints of various origins
Mancel, Catherine. "Modélisation et résolution de problèmes d'optimisation combinatoire issus d'applications spatiales." Toulouse, INSA, 2004. http://www.theses.fr/2004ISAT0011.
In this work we are concerned with combinatorial optimization problems stemming from space missions planning. These huge problems have some common features concerning the type of data, constraints and criteria to be optimized. We focus on linear programming for modeling and solving these problems, associated to methods for search space simplification, using decomposition or some constraint propagation techniques. We more particularly address two problems. The first one concerns a mission which aims at a scientific investigation of Mars. It consists in planning both communication slots between martian probes and a satellite, and experiments on probes. We use linear integer programming to model and solve to optimality the sub-problem of communication slots planning, and we develop an decision-aid oriented method using constraint propagation for experiments planning. The second problem occurs in the context of the french program of Earth observing with satellites. It consists in selecting and scheduling images taken by one satellite in order to maximize a quality criterion. We give a linear model and we propose a column generation approach, based on the Dantzig-Wolfe decomposition of the model, to calculate upper bounds for this problem and in order to solve it
Prado, Carlos. "Un modele de succession vegetale : role des traits biologiques des especes et des contraintes spatiales." Paris 6, 1988. http://www.theses.fr/1988PA066491.
Ollier, Sébastien. "Des outils pour l'intégration des contraintes spatiales, temporelles et évolutives en analyse des données écologiques." Lyon 1, 2004. http://www.theses.fr/2004LYO10293.
Prado, Carlos. "Un Modèle de succession végétale rôle des traits biologiques des espèces et des contraintes spatiales /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37617710h.
Jonquet, Antoine. "Contribution à la modélisation de l'articulation du genou : outils géométriques et cinématiques." Reims, 2007. http://theses.univ-reims.fr/exl-doc/GED00000724.pdf.
This thesis takes place in an interdisciplinary project aiming at the development of a system intended to the re-education of the knee join. My work had consisted in providing cinematic curves of the articulation evolution based real geometrical data. Furthermore, this work fits in an overall realistic human simulation project. From this viewpoint, I have modelled a join (the knee) to validate a general methodology that could be extended to the human skeleton. So, I developed tools for join simulation, both geometric and cinematic. The geometric modelling of the bone surfaces is done with smooth surfaces with global parameters: the radial basis surfaces. They are constructed in two stages from geometrical data of scanned triangular meshes: meshes parameterization, then interpolation. To overcome the dimensionality problem, we offered to improve this method with the use of the partition of unity method. By this way, I defined a smooth parametric surface with global parameters on an open or closed mesh without hole. From this mathematical description of the bone surfaces, appropriate to the lagragian simulation, we defined a set of constraints to express the sliding contact between two bone surfaces. For these constraints we need to introduce new unknowns in the equations of motion. Finally, we returned to the simultaneous constraints handling problem to improve a classical method for activating and deactivating constraints
Côme, Etienne. "Apprentissage de modèles génératifs pour le diagnostic de systèmes complexes avec labellisation douce et contraintes spatiales." Compiègne, 2009. http://www.theses.fr/2009COMP1796.
The main topic of this thesis concerns the formalisation and the resolution of statistical learning problem involving imperfect information on one or several discrete variables of interest. The solution advocates is build on top of the Dempster-Shaffer theory of evidence and a generative approach. We show first, how « soft » labels defined as a Dempster-Shafer basic belief assignments can be employed to define a criterion generalizing the likelihood function which can be used to compute estimates of mixture model parameters. A variant of the EM algorithm dedicated to the optimization of this criterion is furthermore proposed. A similar approach is also studied in the context of independent factor analysis, a parsimonious generative model dealing with several discrete variables. A solution to leverage prior knowledge on the generative process underlying this model is also supplied. Finally, results from a real diagnosis application demonstrates the interest of these proposis. This diagnosis application concerns an essential component of the French railway infrastructure : the track circuit
Mancel, Catherine. "Modelisation et resolution de problemes d'optimisation combinatoire issus d'applications spatiales." Phd thesis, INSA de Toulouse, 2004. http://tel.archives-ouvertes.fr/tel-00009238.
Abid, Saïd. "Optimisation d'épaisseur de structures minces isotropes et composites en présence de non linéarités géométriques." Compiègne, 1995. http://www.theses.fr/1995COMPD793.
Rousse, Sonia. "Apport du paléomagnétisme à l'étude des déformations lithosphériques au Pérou : contraintes spatiales et temporelles sur la construction des Andes." Paris, Institut de physique du globe, 2002. http://www.theses.fr/2002GLOB0008.
Lorrillière, Romain. "Effets des variations temporelles et spatiales des contraintes sur les systèmes écologiques, implications pour l'étude des scénarios de biodiversité." Paris 6, 2011. http://www.theses.fr/2011PA066345.
Maculet, Robert, and JEAN-FRANCOIS PERROT. "Archipel : Intelligence artificielle et conception assistee par ordinateur en architecture. representation des connaissances spatiales,algebre de manhattan, et raisonnement spatial avec contraintes." Paris 6, 1991. http://www.theses.fr/1991PA066564.
Lauvernet, Claire. "Assimilation variationnelle d'observations de télédétection dans les modèles de fonctionnement de la végétation : utilisation du modèle adjoint et prise en compte de contraintes spatiales." Phd thesis, Université Joseph Fourier (Grenoble), 2005. http://tel.archives-ouvertes.fr/tel-00010443.
Verroust-Blondet, Anne. "Etude de problèmes liés à la définition, la visualisation et à l'animation d'objets complexes en informatique graphique." Paris 11, 1990. http://www.theses.fr/1990PA112358.
Nempont, Olivier. "Modèles structurels flous et propagation de contraintes pour la segmentation et la reconnaissance d'objets dans les images : application aux structures normales et pathologiques du cerveau en IRM." Phd thesis, Télécom ParisTech, 2009. http://pastel.archives-ouvertes.fr/pastel-00005269.
Vanegas, Orozco Maria Carolina. "Relations spatiales et raisonnement spatial pour l'interprétation des images d'observation de la Terre utilisant un modèle structurel." Phd thesis, Télécom ParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00583410.
Effendi, R.-Riesdam. "Analyse des mécanismes de dégradation en compression des composites unidirectionnels fibres de carbone-matrice organique et modélisation associée." Toulouse, ENSAE, 1993. http://www.theses.fr/1993ESAE0007.
Minout, Mohammed. "Modélisation des aspects temporels dans les bases de données spatiales." Doctoral thesis, Universite Libre de Bruxelles, 2007. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210672.
Etant donné ces nouveaux besoins, cette thèse se focalise sur la modélisation et l'implantation des aspects temporels dans bases de données. En effet, la conception d'une application de base de données se fait par un enchaînement de trois phases (conceptuelle, logique et physique). Au niveau conceptuel, plusieurs modèles conceptuels ont été proposés intégrant les caractéristiques temporelles et spatiales.
Malheureusement, au niveau logique, les modèles de données des SGBD actuels n'offrent pas les concepts nécessaires pour implanter le modèle conceptuel spatio-temporel. Nous proposons donc de nouvelles règles de traductions d'un schéma conceptuel, basé sur le modèle MADS (Modélisation des Applications à des données spatio-temporelles), en un schéma logique MADSLog pour les modèles cibles à savoir :relationnel et relationnel-objet. Chaque règle transforme un concept structurel, temporel et spatial du modèle MADS en un ou plusieurs concepts supportés par la cible. Par exemple, la propriété spatiale définissant la géométrie d'un type d'objet est traduite par la création d'un nouvel attribut de type spatial dans ce type d'objet. Un outil CASE(Computer-Aided Software Engineering) appelé Schema Translateur est développé dans cette thèse implémentant toutes les règles de traductions.
La traduction de schémas conceptuels en schémas logiques peut impliquer une perte sémantique en raison de la différence de la puissance d'expression entre le modèle conceptuel et le modèle de données des SGBD existants. D'où la nécessité de générer un ensemble de contraintes d'intégrité afin de préserver la sémantique définie dans le schéma conceptuel. Ces contraintes sont exprimées à ce niveau par des formules logiques.
Avec l'apparition de GML (Geographic Markup Language ) qui est conçu pour la modélisation, le transport et le stockage d'informations géographiques. Nous transformons également le schéma conceptuel MADS en GML. De nouveaux schémas GML temporel et spatial sont définis qui peuvent être employés par n'importe application de base de données spatio-temporelle.
Au niveau physique, nous proposons une méthode d'adaptation du schéma logique en schéma physique pour le modèle relationnel-objet.
Elle permet de définir les tables, les types abstraits, les types d'objets, les domaines, etc. Notre proposition permet aussi la génération des contraintes d'intégrité au niveau physique. En effet, chaque contrainte d'intégrité (structurelle, temporelle ou spatiale) qui est définie en calcul logique est exprimée soit directement par des contraintes déclaratives ou soit par des déclencheurs du SGBD choisi. Les déclencheurs spatiaux sont fondés sur les fonctionnalités prédéfinies dans Oracle, alors que les déclencheurs temporels sont basés sur les opérateurs et méthodes appliquées sur les types temporels.
Enfin, la traduction de requêtes est une deuxième clef de cette recherche. Le but de la traduction de requêtes, exprimées en algèbre, étant de reconstituer l'information au sens MADS à partir de la base de données stockées dans le SGDB cible. Elle permet de traduire les expressions algébriques MADS, qui sont définies sur le schéma conceptuel et non sur le schéma physique, en requêtes opérationnelles qui peuvent être exécutées sur une base de données spatiale et temporelle sous un SGBD ou un SIG.
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished
Camara-Rey, Oscar. "Recalage non linéaire d'images TDM et TEP dans les régions thoraciques et abdominales: etude méthodologique et application en routine clinique." Phd thesis, Télécom ParisTech, 2003. http://pastel.archives-ouvertes.fr/pastel-00000903.
Boulil, Kamal. "Une approche automatisée basée sur des contraintes d'intégrité définies en UML et OCL pour la vérification de la cohérence logique dans les systèmes SOLAP : Applications dans le domaine agri-environnemental." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2012. http://tel.archives-ouvertes.fr/tel-00923497.
Ben, Rais Lasram Frida. "Diversité ichtyologique en Méditerranée : patrons, modélisation et projections dans un contexte de réchauffement global." Montpellier 2, 2009. http://www.theses.fr/2009MON20004.
Due to its semi-enclosed shape, to its high species richness and high endemism levels and to its invasiveness, the Mediterranean Sea is one of the most particular and critical ecosystems of the world. The Mediterranean has been intensively studied since the Antiquity, yet foundations underlying fish diversity patterns have been overlooked. In this study, as a first step, we studied fish diversity patterns in the Mediterranean and their determinants. Towards this objective, we built the first comprehensive database on the spatial distributions of the 619 Mediterranean fish species. We then carried out spatial analyses in order to assess the relative contribution of historical and geometric contingencies as well as environmental influences in shaping fish biodiversity patterns. In a second step, we analyzed the correlates of dispersal success of exotic species and we assessed the spatial congruence with the endemic ichtyofauna within a global warming context. Finally, we modeled the present climatic envelopes of the most vulnerable Mediterranean fish species, i. E. The endemic species. We used those models to project expected spatial distributions of endemic species according to a global warming scenario in order to identify winner versus loser species as well as areas where a strong species turnover would occur. We showed that geometric constraints, primary production and temperature have an influence on species diversity patterns. It also appeared that the climate and the year of introduction into the Mediterranean are key determinants of the dispersal success of Lessepsian species. Within a global warming context, our results revealed an increasing spatial congruence between endemic and exotic fish faunas and for the latter, deep modifications in their assemblages expected in 2041-2060 and 2070-2099. In sum our results suggest that endemic species undergo a biotic pressure via exotic species and an abiotic pressure via global warming. The additional and potentially the synergetic effect of those pressures is likely to increase endemic species vulnerability
Boulil, Kamal. "Une approche automatisée basée sur des contraintes d’intégrité définies en UML et OCL pour la vérification de la cohérence logique dans les systèmes SOLAP : applications dans le domaine agri-environnemental." Thesis, Clermont-Ferrand 2, 2012. http://www.theses.fr/2012CLF22285/document.
Spatial Data Warehouse (SDW) and Spatial OLAP (SOLAP) systems are Business Intelligence (BI) allowing for interactive multidimensional analysis of huge volumes of spatial data. In such systems the quality ofanalysis mainly depends on three components : the quality of warehoused data, the quality of data aggregation, and the quality of data exploration. The warehoused data quality depends on elements such accuracy, comleteness and logical consistency. The data aggregation quality is affected by structural problems (e.g., non-strict dimension hierarchies that may cause double-counting of measure values) and semantic problems (e.g., summing temperature values does not make sens in many applications). The data exploration quality is mainly affected by inconsistent user queries (e.g., what are temperature values in USSR in 2010?) leading to possibly meaningless interpretations of query results. This thesis address the problems of logical inconsistency that may affect the data, aggregation and exploration qualities in SOLAP. The logical inconsistency is usually defined as the presence of incoherencies (contradictions) in data ; It is typically controlled by means of Integrity Constraints (IC). In this thesis, we extends the notion of IC (in the SOLAP domain) in order to take into account aggregation and query incoherencies. To overcome the limitations of existing approaches concerning the definition of SOLAP IC, we propose a framework that is based on the standard languages UML and OCL. Our framework permits a plateforme-independent conceptual design and an automatic implementation of SOLAP IC ; It consists of three parts : (1) A SOLAP IC classification, (2) A UML profile implemented in the CASE tool MagicDraw, allowing for a conceptual design of SOLAP models and their IC, (3) An automatic implementation based on the code generators Spatial OCLSQL and UML2MDX, which allows transforming the conceptual specifications into code. Finally, the contributions of this thesis have been experimented and validated in the context of French national projetcts aimming at developping (S)OLAP applications for agriculture and environment
Drareni, Jamil. "Exploitation de contraintes photométriques et géométriques en vision. Application au suivi, au calibrage et à la reconstruction." Phd thesis, 2010. http://tel.archives-ouvertes.fr/tel-00593514.
Draréni, Jamil. "Exploitation de contraintes photométriques et géométriques en vision : application au suivi, au calibrage et à la reconstruction." Thèse, 2010. http://hdl.handle.net/1866/4868.
The topic of this thesis revolves around three fundamental problems in computer vision; namely, video tracking, camera calibration and shape recovery. The proposed methods are solely based on photometric and geometric constraints found in the images. Video tracking, usually performed on a video sequence, consists in tracking a region of interest, selected manually by an operator. We extend a successful tracking method by adding the ability to estimate the orientation of the tracked object. Furthermore, we consider another fundamental problem in computer vision: cali- bration. Here we tackle the problem of calibrating linear cameras (a.k.a: pushbroom) and video projectors. For the former one we propose a convenient plane-based cali- bration algorithm and for the latter, a calibration algorithm that does not require a physical grid and a planar auto-calibration algorithm. Finally, we pointed our third research direction toward shape reconstruction using coplanar shadows. This technique is known to suffer from a bas-relief ambiguity if no extra information on the scene or light source is provided. We propose a simple method to reduce this ambiguity from four to a single parameter. We achieve this by taking into account the visibility of the light spots in the camera.
Cette thése a été réalisée dans le cadre d'une cotutelle avec l'Institut National Polytechnique de Grenoble (France). La recherche a été effectuée au sein des laboratoires de vision 3D (DIRO, UdM) et PERCEPTION-INRIA (Grenoble).