Les structures assemblées par points de soudure doivent satisfaire à un grand nombre de critères de performance, portant entre autres sur des aspects statiques, dynamiques, acoustiques, ou crash, qui sont fortement influencés par le nombre et la position des points de soudure. De plus, certains d’entre eux peuvent être défaillants en sortie de ligne d’assemblage ou le devenir au cours de la vie du véhicule, ce qui induit des dispersions des performances. Le challenge est donc de déterminer, dans un temps d’analyse raisonnable, le nombre et la répartition optimale des points de soudure permettant la vérification des objectifs de performance tout en garantissant le meilleur compromis entre le coût de fabrication et la robustesse des performances. Une procédure adaptative est proposée, permettant à chaque itération d’ajouter et de supprimer des points de soudure, afin d’obtenir une conception robuste. Une procédure itérative de robustesse info-gap est également présentée, afin d’analyser l’impact de la perte des points de soudure les plus influents. On définit ainsi une procédure de contrôle qualité, portant sur un petit nombre de points de soudure, permettant de garantir l’homogénéité des performances des structures fabriquées en série. Toutes les méthodologies sont validées sur une caisse en blanc de véhicule industriel.En pratique, la conception doit satisfaire plusieurs critères antagonistes. La procédure adaptative est donc étendue à l’optimisation multi-objectifs, afin d’obtenir le meilleur compromis possible en fonction des critères considérés. Une illustration portant sur l’optimisation dynamique et vibro-acoustique d’une cavité passager est finalement mené / Spot welded structures must satisfy a large variety of performance characteristics including static, noise, vibration and harshness and crash, which are strongly influenced by the numbers and positions of the spot welds. Moreover, some spot welds may be missing when structures leave the assembly line or break during lifetime of vehicle, inducing large variations in the performance characteristics. The challenge is to find the best locations and number of spot welds to achieve the performance goals while taking into account the trade-offs between manufacturing cost and robust to uncertainty in reasonable time frame. An adaptive optimization procedure is proposed, which iteratively adds and removes spot welds to obtain the robust design efficiently. An iterative procedure is also proposed to obtain the info-gap robustness curve, which allows analyzing the impact of the loss of the most influential spot welds on performance. This leads to define a quality control procedure for a small number of spot welds to guarantee the performance of a population of nominally identical structures within acceptable limits. All the methodologies are validated on a full industrial body-in-white of a vehicle.In practice, the design must satisfy several stringent and conflicting objectives simultaneously. Thus, we extend the adaptive procedure to handle multi-objective problems using the weight-sum approach reflecting the importance given to individual spot welds to obtain efficient solutions in the objective space. Finally, we propose a strategy to optimize the vibro-acoustic behavior of the passenger cabin of a vehicle by designing the numbers and positions of the spot welds.

La gestion de la distribution de l’énergie électrique dans un système multi-source (véhicule hybride électrique) est primordiale. Elle permet d’augmenter les performances du système en minimisant la consommation de combustible utilisée par la source principale, tout en respectant la demande et les différentes contraintes de fonctionnement de la chaîne énergétique et de sécurité du système. Dans cette thèse, dans le cas où le profil de mission est connu, une approche combinatoire est proposée en modélisant le problème de gestion d’énergie sous la forme d’un problème d’optimisation avec satisfaction des contraintes. Celui-ci est résolu par une méthode exacte issue de la recherche opérationnelle, conduisant à des solutions optimales en des temps de calcul fortement réduits en comparaison avec ceux obtenus par l’application de la programmation dynamique ou la commande optimale. Pour éprouver la sensibilité aux perturbations, une étude de robustesse est menée sur la base de l’analyse de la solution de pire-cas d’un scénario sur des profils de mission d’un véhicule. Les cas pratiques d’utilisation imposent de ne connaître la demande du moteur électrique qu’à l’instant présent, selon le mode de conduite du chauffeur. Afin de gérer l’énergie du véhicule en temps réel, un algorithme en ligne, basé sur une approche de type floue, est développé. Pour mesurer la qualité de la solution floue obtenue, une étude de performance est réalisée (recherche de l’optimum global), en ayant recours à une optimisation hors-ligne sur des profils de mission de référence, basée sur une modélisation non linéaire du problème de gestion d’énergie. Les résultats obtenus ont permis de valider la qualité de la solution floue résultante. / Managing the distribution of electrical energy in a multi-source system (hybrid electric vehicle) is paramount. It increases the system performance by minimizing the fuel used by the primary source, while respecting demand, the differents operating constraints of the energy chain and system security. In this thesis, where the mission profile is known, a combinatorial approach is proposed by modeling the problem of energy management as an optimization problem with constraint satisfaction. The problem is solved using an exact method from operations research, leading to optimal solutions with reduced computation time in comparison with those obtained by applying dynamic programming or optimal control strategies. To test the perturbation sensitivity, robustness study is conducted, based on the analysis of the worst-case solution of the worst scenario, which can be achieved on the vehicle mission profile. In practical cases, the vehicle demand is unknown, and we have only the information about the instantaneous demand, which depends on driving style of the driver. In order to manage on line the energy of the vehicle, an on-line algorithm, based on a fuzzy approach is developed. To measure the quality of the fuzzy solution obtained, a performance study is carried out (finding the optimum solution), using an off-line optimization under reference mission profiles, based on non-linear modeling of the power management problem. The results were used to validate the quality of the resulting fuzzy solution.

L’intelligibilité de la parole est un véritable enjeu dans la prise en charge des personnes présentant un trouble de la production de la parole pathologique (TPPP). L’usage de ce terme, avec un sens commun recouvrant le domaine de la compréhension, et un sens restreint répondant à la mesure du transfert d’information linguistique dans un contexte de test, entretient une ambigüité ; ambigüité qui entrave le développement des concepts de prise en charge. L’objectif de ce travail de thèse est, à travers trois groupes d’expériences autour de la notion d’intelligibilité, de proposer un cadre conceptuel pouvant servir à organiser la prise en charge des TPPP et à identifier les questions de recherche fondamentale impliquées dans la problématique de l’intelligibilité dans les TPPP.L’objectif principal du premier groupe d’expériences est d’étudier la place de l’intelligibilité dans les stratégies cognitives sous-jacentes à la perception de la parole pathologique. La méthode utilisée est une catégorisation libre..La deuxième série d’expériences est consacrée à la manière dont un groupe d’experts réalise une tâche de jugement de sévérité comparée à une tâche de jugement d’intelligibilité. Le troisième groupe d’expériences cherche à déterminer les cibles les plus efficaces dans la prise en charge des TPPP. Elle repose sur l’hypothèse suivante : la conservation d’une perception juste d’un phonème ou d’une syllabe malgré sa distorsion pathologique permet de déterminer sa contribution à l’intelligibilité et participe à la définition de la notion de robustesse perceptive. Pour tester cette hypothèse, une méthode d’analyse du taux de perception obtenu par un jury d’auditeurs, en fonction du degré de vraisemblance issu d’un système automatique de reconnaissance a été formalisée. Les résultats de ces expériences, interprétées sous l’éclairage croisé des théories sur la perception et de la production de la parole et des modèles de santé, nous ont permis de proposer une définition des différents concepts dans la perspective de la classification internationale du fonctionnement. / The intelligibility of speech is a real challenge for the management of speech disorders. The use of this word, with a common meaning of comprehension and, a specific meaning in a context of test, of measurement of the information transfer, carries some ambiguity, which could hinder the concept of management.The purpose of this work is to propose a conceptual framework for the management of pathological speech production (PSP) through three kinds of experiments. The aim of the first set of experiments is to study the place of the intelligibility within the underlying cognitive strategies of the perception of pathological speech.A free classification method is used with a corpus of sentences read by 33 speakers: 20 patients with speech disorders (a pathological speech production due to neurological diseases or sequellae of cancer or malformative lesions) and 13 normal subjects. The second set of experiments studies the way an expert group performs evaluation of severity compared to evaluation of intelligibility. During an off line experiment, the corpus of the previous study filled by a corpus of different sentences by speaker, was presented to 5 judges (logopedists and phoniatriciansThe third group of experiments looks for the most efficient targets for managing speech disorders. It‘s based on the following assumption: the preservation of a correct perception of a phoneme or a syllable, despite its pathological distortion, allows to determine its contribution to intelligibility and participates to the notion of perceptive robustness. For testing this assumption, was proposed a method of analysis by the identification score (obtained by a jury of listeners) function of the degree of” plausibility (obtained by an automatic system for speech recognition). The outcome of these experiments, adopting the points of view of some perception theories of SD mixed with health models allow us to precise the definition of the main concepts in the prospect of the international classification of functioning.

Wind turbine modelling using doubly-fed induction generators is a well-known subject. However, studies have tended to focus on optimising the components of the system rather than considering the interaction between the components. This research examines the interaction of the control methods for a doubly-fed induction generator (DFIG) in a wind turbine application integrating them with the crowbar protection control and DC-link brake control to make the best use of the converter. The controls of the rotor-side and the grid-side converters of the DFIG model are both well established and have been shown to work. Typically the crowbar protection is designed in order to protect the rotor-side converter and the power electronic components of the DFIG system from high currents occurring in the rotor due to the faults. The DC-link brake-overvoltage protection is also designed to prevent the overcharging of the DC-link capacitor placed between the rotor-side converter and the grid-side converter. In order to show that these protection schemes work and with thought can co-ordinate with each other, tests consisting of a number of balanced three-, two- and one-phase voltage sags are applied to the network voltage. The main contributions of this thesis are establishing operational tuning and design limits for the controllers and system subassemblies. This is to minimise the electrical subsystem interaction while maintaining adequate performance, and have an improved DC-link control. This work also includes a full electrical system study of the wind turbine and an essential literature review on significant references in the field of the DFIG wind turbine system modelling, control and protection. Specifically this research project makes a number of novel contributions to the literature: enhanced DC voltage control including operating point sensitivity analysis and dynamic stiffness assessment, sensitivity and robustness analyses of the power loop control and control loop segmentation by appropriately tuning the controller loops.

Joints are the most critical elements in a steel framed structure. In most design guides or codes, the joints are assumed to a have higher fire resistance than the connected structural members because of the lower temperatures in the joints. However, in severe fire conditions, a connected beam's temperature may be higher than its limiting temperature and the beam may develop catenary action when the beam’s axial shortening from large deflections becomes greater than the beam’s thermal expansion. This beam catenary action force could fracture the joints, increasing the risk of progressive collapse. This research focuses on the interaction between joints and the connected steel beams and columns in steel framed structures in fire, including how the behaviour of a joint-beam assembly may be efficiently analyzed and how the joints may be constructed to achieve high degrees of catenary action. Three methods of simulating the joint behaviour in fire have been developed and implemented in the commercial finite element software ABAQUS. In the first modelling method, all structural members, including the connections, were simulated using detailed solid elements to enable detailed behaviour of the structure to be faithfully represented. In the second method, the columns were represented by conventional line (beam) elements, the joints were represented using springs (Connector Elements) based on the component based method, and the beam was modelled using solid elements. In the third method, the joints were modelled using springs as in the second method and the beam and columns were simulated using line (beam) elements. As expected, the detailed simulation method was extremely time-consuming, but was able to produce detailed and accurate results. The simulation results from the second and third methods contained some inaccuracies, but depending on the simulation objective, their simulation results may be acceptable. In particular, the third simulation method was very efficient, suitable for simulating complete frame structures under very large deflections in fire. The first method (detailed finite element method) was then used to investigate how to change the joint details to increase the survivability of restrained steel beams and beam-column assemblies at high temperatures since it enables detailed behaviour of the structure to be faithfully represented. It is found that by improving joint deformation capacity, in particular, using extended endplate connection with fire resistant bolts, very high temperatures can be resisted. The frame robustness in fire was investigated using the third simulation method to save computation time. The simulation structure was three-bay by three-floor and different scenarios of fire location, fire spread and initial structural damage were considered. The simulation results show that once failure of a column occurs, progressive collapse of the structure could be easily triggered and it would be rather futile to only enhance the joint capacity. Therefore, in addition to the measures of improving joint capacities (both rotation and strength), design of the affected columns should include consideration of the additional catenary forces from the connected beams and the increased effective lengths. Furthermore, the lateral bracing system should be ensured to provide the structure with lateral restraint.

A crescente capacidade do poder computacional e a proliferação de dispositivos ao nosso redor vem permitindo o desenvolvimento de novas e sofisticadas interfaces para interação humano-computador que reagem à presença e ao estado de seus usuários. Como o olhar tem a capacidade de transmitir muitas informações sobre o usuário, rastreadores de olhar, dispositivos que estimam a direção para onde uma pessoa olha, tem papel importante no desenvolvimento de tais interfaces. Entre suas aplicações temos o auxílio a pessoas com dificuldades motoras, que podem utilizar um rastreador de olhar como substituto ao mouse, aplicações de diagnóstico, que estudam evidências do comportamento humano, ou ainda o desenvolvimento de interfaces que utilizem a informação sobre o olhar como um canal a mais de comunicação com o usuário para perceber suas intenções. Muitas técnicas para atingir tal objetivo foram desenvolvidas mas as tradicionais ainda oferecem certas dificuldades de uso para seus usuários como a intolerância a movimentos de cabeça e a necessidade de calibração por sessão de uso. Neste trabalho fizemos um levantamento de uma série de técnicas de rastreamento de olhar, indo das mais tradicionais até algumas mais recentes que visam melhorar a facilidade de uso destes sistemas. Uma das técnicas mais promissoras utiliza múltiplas fontes de luz fixadas nos cantos do monitor do computador. Através da análise da posição dos reflexos gerados por essas fontes de luz sobre a córnea, juntamente com a informação da posição da pupila, presentes em imagens capturadas do olho, é possível estimar o ponto observado no monitor. Devido às suas vantagens ela foi escolhida para estudo mais detalhado e implementação. Extensos testes utilizando simulações foram realizados para avaliar seu desempenho. Foi também desenvolvida uma extensão dessa técnica, utilizando um modelo mais preciso do olho, visando melhorar sua precisão. Ao final apresentamos nossa implementação, baseada nessa extensão da técnica original, que é tolerante a movimentação da face e mostramos os resultados obtidos em testes realizados com um grupo de usuários. / Recent advances in computing power and the proliferation of computing devices around us allowed the development of new computer interfaces which can react to the presence and state of its users. Since gaze can transmit a lot of information about the user, gaze trackers, devices that can estimate the direction which a person is looking at, have an important role in the development of such interfaces. Among gaze tracking applications, we have aid for people with limited motor skills, human behavior studies, and the development of interfaces that can take gaze information as an additional communication channel with the user. Lots of techniques have been developed to reach this goal, but they have some problems that make them hard to be widely used. These problems are the need of calibration for each use session and the need to keep the user\'s head still. In this work we studied some of the existing gaze tracking techniques, from the more traditional ones to more recent ones. One of the most interesting techniques makes use of multiple light sources fixed at the monitor\'s corners. By analyzing the positions of corneal reflections and the pupil present in captured images of the eye, it is possible to estimate the gaze point on the monitor screen. Due to its advantages this technique was chosen for a deeper study and implementation. Lots of experiments using simulated data have been carried out to validate the technique. Using a more accurate model of the eye, an extension for this technique was also developed to increase its precision. Finally, we present our implementation, that allows for large head movement, as well as test results obtained from real users.

Dans le secteur médical tout particulièrement, la qualité du geste est primordiale et les professionnels doivent être formés par la pratique pour acquérir un niveau de compétences compatible avec l'exercice de leur métier. Depuis une dizaine d'année, les simulateurs informatiques aident les apprenants dans de nombreux apprentissages mais ils doivent encore être associés à des travaux pratiques sur mannequins, animaux ou cadavres, qui pourtant n'offrent pas toujours suffisamment de réalisme par rapport aux vrais patients, et sont coûteux à l'usage. Aussi, leur formation s'achève généralement sur de vrais patients, ce qui présente des risques. Les simulateurs haptiques (fournissant une sensation d'effort) deviennent aujourd'hui une solution plus appropriée car ils peuvent reproduire des efforts résistant réalistes et proposer une infinité de cas d'étude pré-enregistrés. Cependant, apprendre seul sur un simulateur n'est pas toujours aussi efficace qu'un apprentissage "à quatre mains" (celles de l'instructeur et de l'apprenant manipulant les mêmes outils en coopération). Cette étude propose donc un système haptique de formation pratique à deux utilisateurs : l'instructeur et l'apprenant, interagissant chacun à travers leur propre interface haptique. Ils collaborent ainsi, avec des outils et un environnement de travail soit réels (l'outil est manipulé par un robot) soit virtuels. Une approche énergétique, faisant appel notamment à la modélisation par port-Hamiltonien, a été utilisée pour garantir la stabilité et la robustesse du système. Une étude comparative (en simulation) avec deux autres systèmes haptiques multi utilisateurs a montré l'intérêt de ce nouveau système pour la formation pratique. Il a été développé et validé expérimentalement sur des interfaces à un seul degré de liberté. Son extension à six degrés de liberté est facilitée par les choix de modélisation. Afin de pouvoir utiliser le système quand les deux protagonistes sont éloignés, cette étude propose des pistes d'amélioration qui ne sont pas encore optimisées. / More particularly in the medical field, gesture quality is primordial. Professionals have to follow hands-on trainings to acquire a sufficient level of skills in the call of duty. For a decade, computer based simulators have helped the learners in numerous learnings, but these simulations still have to be associated with hands-on trainings on manikins, animals or cadavers, even if they do not always provide a sufficient level of realism and they are costly in the long term. Therefore, their training period has to finish on real patients, which is risky. Haptic simulators (furnishing an effort feeling) are becoming a more appropriated solution as they can reproduce realist efforts applied by organs onto the tools and they can provide countless prerecorded use cases. However, learning alone on a simulator is not always efficient compared to a fellowship training (or supervised training) where the instructor and the trainee manipulate together the same tools. Thus, this study introduces an haptic system for supervised hands-on training: the instructor and the trainee interoperate through their own haptic interface. They collaborate either with a real tool dived into a real environment (the tool is handled by a robotic arm), or with a virtual tool/environment. An energetic approach, using in particular the port-Hamiltonian modeling, has been used to ensure the stability and the robustness of the system. This system has been designed and validated experimentally on a one degree of freedom haptic interface. A comparative study with two other dual-user haptic systems (in simulation) showed the interest of this new architecture for hands-on training. In order to use this system when both users are away from each other, this study proposes some enhancements to cope with constant communication time delays, but they are not optimized yet.

Cílem této práce je prezentovat metody pro akceleraci výpočtů stínů a osvětlení.  Práce se zabývá akcelerací na vzorek přesných stínů pomocí stínových těles na různých platformách. Obsahem práce je také zvýšení přesnosti stínových map a zvýšení přesnosti osvětlování scény s mnoha světly.

The diploma thesis describes Climate Change and impacts of Climate Change on the development of the water management analyis of reservoir strorage capacity. The development of climate chang influence on reserviors storage capacity is presented until 2100. It also gives a detailed online downscaling description.

This thesis deals with an electron scattering in STEM microscopy on objects with dif-ferent shapes, such as cuboid, sphere and hollow capsule. Monte Carlo simulations are used for description of multiple electron scattering. Except the theoretical analysis of the electron scattering and simulation methods, the thesis contains design and realiza-tion of an algorithm simulating electron scattering in given objects. In addition, there is a design for robustness evaluation of the simulation, based on comparison between results and known signals for a given object. Reliability of the algorithm was verified by experimental measurements of the electron scattering on a carbon layer.