Les mémoires à changement de phase sont l'un des candidats les plus prometteurs pour la prochaine génération de mémoires non-volatiles. Un intense effort de recherche est requis pour optimiser les matériaux à changement de phase (PC) utilisés dans ces mémoires. En particulier, il a été démontré que le dopage améliore les propriétés de rétention des dispositifs. Par ailleurs, l'étude des effets de réduction de taille et des effets des matériaux d'interface sur les propriétés des matériaux à changement de phase est encore un sujet de recherche ouvert. Dans ce contexte, la première partie de la thèse est dédiée à l'investigation de la structure locale de GeTe amorphe dopé avec C ou N. L'effet du dopage sur la structure a été observé expérimentalement via l'apparition d'un nouveau pic dans la fonction de distribution de paires de GeTe dopé, ce qui montre la formation d'une nouvelle liaison interatomique absente dans le matériau non dopé. La présence de nouvelles configurations incluant le carbone et l'azote a été confirmée par des simulations ab initio. L'objet de la deuxième partie de la thèse est l'influence de la réduction de taille sur la cristallisation de Ge2Sb2Te5 (GST). Des agrégats nanométriques de GST ont été fabriqués par pulvérisation puis déposés et étudiés par diffraction des rayons X en utilisant le rayonnement synchrotron. Dans l'état cristallisé une très forte déformation positive des agrégats est observée et attribuée à la matrice d'Al2O3 qui entoure les agrégats. La température de cristallisation des agrégats est de 25°C plus élevée que celle d'un film de GST de 10 nm déposé dans les mêmes conditions. Ce résultat est encourageant pour les futurs développements des mémoires à changement de phase car il montre que l'effet de réduction de taille sur la température de cristallisation peut-être faible. La troisième et dernière partie de la thèse est dédiée à l'investigation des effets des matériaux d'interface sur la température de cristallisation de films minces de GeTe et GST par des mesures de réflectivité et de diffraction des rayons X. Pour les deux matériaux, la température de cristallisation de films de 100 nm est plus grande pour une interface avec du Ta que pour une interface avec du TiN ou du SiO2. Une différence aussi marquée n'était jamais montré auparavant. Les résultats suggèrent que l'interface SiO2/GeTe est énergétiquement favorable pour la nucléation et la croissance de grains avec une orientation préférentielle et que les mécanismes de nucléation et croissance sont différents pour différents matériaux d'interface. / Phase Change Memories (PCM) are one of the best candidates for the next generation of non volatile memories. A great research effort is still needed in order to optimize the properties of phase change (PC) materials which are used in PCM devices. In particular, doping has been demonstrated to improve retention in devices. Moreover, a study of the effect of scaling and interface material on PC materials properties is still an open research field. In this context, the first part of the thesis is dedicated to investigate the local structure of C or N doped amorphous GeTe. The impact of doping is observed experimentally with the appearance of a new peak in the pair distribution function of doped GeTe, indicating the formation of a bond at a new distance that is absent in the undoped amorphous material. The presence of new environments involving carbon and nitrogen is confirmed through ab initio simulations. The subject of the second part of this thesis is the impact of confinement on Ge2Sb2Te5 (GST) crystallization mechanism. Nano-sized clusters of GST have been made by sputtering, deposited and then studied through X-ray diffraction using synchrotron radiation. The crystalline clusters experience a tensile strain that can be ascribed to the effect of the embedding Al2O3 matrix. Their crystallization temperature has been found to be only 25°C higher than the one observed for a thin film of GST of 10 nm deposited under the same conditions. This result is positive for the future development PCM because it indicates that the scaling effect on the crystallization temperature in phase change material can be small. The third and last part of the thesis is dedicated to the investigation of the interface material effect on the crystallization temperature of GeTe and GST thin films through reflectivity and X-ray diffraction measurements. In both GeTe and GST film 100 nm thick interfaced with Ta the crystallization temperature is higher than in the case of TiN or SiO2 interface. Such an interface effect on relatively thick films was never reported before. The results suggest that the SiO2/GeTe interface is energetically favourable for the nucleation and growth of grains with a preferred orientation and that nucleation and growth mechanisms are different for different interface materials.

La connaissance, et plus particulièrement, la gestion des connaissances est un enjeu stratégique qui peut fournir un avantage concurrentiel non négligeable dans une économie compétitive et dynamique. Cependant, ce domaine possède un caractère interdisciplinaire indéniable. En effet, il est traité par de multiples disciplines telles que les sciences de l’information, l’informatique, la psychologie, l’économie ou les sciences de l’ingénierie.Les travaux de recherche présentés dans ce manuscrit ont eu lieu dans un contexte CIFRE (Conventions Industrielles de Formation par la REcherche). Le sujet initial est né de la collaboration entre l’équipe « Conception Collaborative » du laboratoire G-SCOP (laboratoire Grenoblois dédié aux Sciences de la Conception, de l'Optimisation et de la Production) et de la société BASSETTI, éditeur et intégrateur de la solution logiciel TEEXMA®.Dans le cadre des travaux présentés dans ce manuscrit, notre objectif a été d'étudier comment modéliser les processus de transfert de connaissance afin de mieux comprendre la façon dont ces derniers se mettent en place au sein des organisations. L’outil de modélisation proposé dans cette thèse repose en partie sur la réutilisation de modèles existants trouvés dans la littérature et sur une méthodologie d'observation des participants.Les recherches effectuées se sont déroulées en suivant une méthodologie de type recherche intervention. Afin de répondre à ce sujet, nous avons donc pu tester notre outil de modélisation à travers plusieurs études de cas terrain. Ces études ont permis de valider la première partie de nos hypothèses. Après cette phase de validation, nous avons cherché à évaluer l’appropriation de l’utilisation de notre outil de modélisation à la suite de formations. En parallèle, nous avons inclus notre outil de modélisation dans une démarche plus globale afin de diagnostiquer des situations de transfert de connaissance. Cette démarche globale a ensuite été appliquée à deux études de cas. Enfin nous avons dérivé l’usage de la démarche précédente. Cette fois ci, l’outil de modélisation est utilisé pour analyser les usages liés à des outils informatiques. / Knowledge, and more precisely, knowledge management, is a strategic issue that can provide a significant competitive advantage in a competitive and dynamic economy. However, this field has an undeniable interdisciplinary character. Indeed, it is treated by multiple research areas such as information science, computer science, psychology, economics or engineering sciences.The research presented in this thesis occurred in a CIFRE context (French Industrial Conventions). The initial research topic was born from the collaboration between the "Collaborative Design" team of the G-SCOP laboratory (Grenoble laboratory dedicated to the Sciences of Design, Optimization and Production) and the company BASSETTI, editor and integrator of the TEEXMA® software solution.As part of the work presented in this manuscript, our goal has been to study how to model knowledge transfer processes for a better understanding of how these processes are implemented within organizations. The modelling tool proposed in this thesis relies in part on the reuse of existing models found in the literature and on a participant observation methodology.The research carried out was conducted following an intervention research methodology. To answer this question, we were able to test our modelling tool through several case studies. These studies allowed to validate the first part of our hypotheses. After this validation phase, we sought to evaluate the appropriation of the use of our modelling tool after knowledge management trainings. In parallel, we have included our modelling tool in a more global approach to diagnose situations of knowledge transfer. This global approach was then applied to two case studies. Finally, we reused the previous approach. This time, the modelling tool was used to analyse uses related to computer tools.

Orientador: Angelo Del Vecchio / Banca: José Antônio Segatto / Banca: Rogério Baptistini Mendes / Resumo: O presente trabalho estuda as transformações sofridas pelas elites econômicas e políticas paulistas durante o processo de reforma do Estado brasileiro ocorrido no período de 1990 a 2002. Busca-se entender a transformação sofrida pelo Estado Brasileiro desde 1980 até os dias atuais, a qual resultou na substituição do modelo desenvolvimentista para o liberalgerencial, as razões de sua crise e as conseqüências em relação aos atores sociais aqui estudados. Com base em um modelo que busca a intersecção entre os conceitos de classe dominante e elites, procura entender o comportamento dos dirigentes políticos no período e quais as razões que levaram às substituições ocorridas entre estas a partir de 1990, com a ascensão de um novo grupo político. Ainda, no que tange às elites econômicas, como a crise econômica dos anos 80 alterou a composição dessas elites, sendo os empresários ligados ao setor industrial substituídos por outros alinhados aos novos setores da economia que emergiram dos processos de reforma do Estado, entre os quais os de serviços, surgidos das privatizações e o financeiro. Apresenta ainda dados empíricos que apontam para a direção das hipóteses trabalhadas, auxiliando na visualização das transformações que se deseja demonstrar. Ao final, propõe a discussão acerca do modelo nacional-desenvolvimentista e de seu futuro enquanto ideologia na sociedade atual / Abstract: The present work studies the transformation occurred by the economic elite and São Paulo State politics during the process of the Brazilian state reformation occurred on 1990 to 2002. We look for to understand the transformation occurred by the Brazilian State since 1980 until now, which resulted on the substitution of the developmental model to the managementliberal model, the reasons of its crisis and the consequences toward the social actors studied here. With basis in a model that searches the meeting point between the concepts of dominant class and elites, looking for to understand the behavior of the politics chairperson on the period and what reasons took to the occurred substitution between them since 1990, with the rising of a new politic group. Still, about the economics elites, with de economics crisis in the 80's changed the composition of these elites, so the business men connected to the industrial housing substituted for others aligned to the new economy sectors that emerged from the process of the State reformation, between them there were the services, arise from the privatization, and the financial services. Still, this study presents empirical datum which point to the directions of the worked hypothesis, helping on the visualization of the transformation that is to be demonstrated. At last, it is proposed a discussion about the nationaldevelopmental model and its future as ideology in the present society / Mestre

This research aims to model the microstructure development of Si-containing bainitic free-machining steel, including allotriomorphic ferrite, idiomorphic ferrite, pearlite, Widmanstatten ferrite, bainite and martensite. The effect of recalescence has been included to give a better estimation of the cooling curve under natural cooling conditions. A model for estimating retained austenite size distribution in the carbide-free bainitic microstructure has been developed. Manganese sulphide particles are used in the free-machining steel to break chips during machining; its effect on the prior austenite grain size has been investigated, taking account of the sulphide shape. The theories of all the major solid state phase transformations involved in steel are reviewed in chapter 2. The theory of the simultaneous transformation model is presented in chapter 3.uu A recalescence model dealing with the heat of reaction has been developed in chapter 5 for bar-shaped products. The model is based on the integration of a heat transfer model, considering latent heat generation, into the simultaneous transformation framework. It has been found that latent heat can greatly affect the transformation, especially in the case of pearlite and Widmanstatten ferrite. Chapter 6 presents the model for estimating the size distribution of retained austenite regions. The model builds on the random division of an austenite grain by bainite sheaves, which means the sizes of the two new compartments generated by the division of an austenite grain by a bainite sheaf are allocated randomly. The next compartment to be divided is also chosen at random. Good agreement between prediction and experiment has been achieved for high carbon carbide-free bainitic microstructures. The transition temperature from upper to lower bainite is modelled in chapter 7. The model compares the time required for decarburising a supersaturated bainitic ferrite platelet and that for cementite precipitation within the ferrite platelet. Manganese, silicon and chromium are considered in the model. It is suggested that carbon and manganese favour lower bainite, whereas silicon promotes upper bainite. The effect of manganese sulphide particles on austenite grain boundary motion has been studied in chapter 8. These rod-shaped particles span many austenite grains; the result shows that the long rod-shaped particles are more effective in pinning the austenite grain boundary than spheres of the same volume, or even strings of identical spheres with the same total volume. Experimental work is presented in chapters 9 and 10. In situ synchrotron X-ray study of the bainite transformation reveals that the distribution of carbon in the residual austenite becomes heterogeneous as transformation progresses. Low carbon regions transform preferentially into martensite during cooling after isothermal bainite transformation. The partitioning of carbon was found to lag behind the bainite transformation; more time is needed as the transformation temperature is reduced. Tetragonality was not observed in either the bainitic ferrite or martensite, because the carbon content of the alloy is relatively low, and the Zener ordering temperature is below the bainite and martensite transformation temperature. No significant difference was observed in the kinetics of bainite transformation between the high sulphur and low sulphur steel.

Dans cette thèse, nous décrivons comment on peut utiliser un diagramme de séquence UML avec des contraintes de temps MARTE pour spécifier complètement le comportement des systèmes à base de composants tout en faisant abstraction des rôles fonctionnels des composants. Nous avons proposé une approche qui permet d'analyser ces spécifications d'une manière modulaire. Pour cela, nous avons attribué une sémantique opérationnelle aux diagrammes de séquence en les traduisant vers les TIOSTS qui sont des automates symbolique et temporisé. Nous avons utilisé des techniques d'exécution symbolique pour calculer les exécutions du système sous la forme d'un arbre symbolique. Nous avons défini des mécanismes de projection pour extraire l'arbre d'exécution associé à un composant sous-jacent. L'arbre résultant de la projection caractérise les comportements attendus du composant et peut être utilisé comme une référence pour valider le système bout par bout. Pour ce faire, nous nous sommes intéressés à des techniques de test. Nous avons présenté un résultat qui ramène la conformité du système à la conformité des composants qui le composent. Sur la base de ces résultats, nous avons proposé une méthodologie incrémentale de test basé sur des spécifications décrites sous la forme de diagrammes de séquence. / In this thesis, we describe how to use UML sequence diagrams with MARTE timing constraints to specify entirely the behavior of component-based systems while abstracting as much as possible the functional roles of components composing it. We have shown how to conduct compositional analysis of such specifications. For this, we have defined operational semantics to sequence diagrams by translating them into TIOSTS which are symbolic automata with timing constraints. We have used symbolic execution techniques to compute possible executions of the system in the form of a symbolic tree. We have defined projection mechanisms to extract the execution tree associated with any distinguished component. The resulting projected tree characterizes the possible behaviors of the component with respect to the context of the whole system specification. As such, it represents a constraint to be satisfied by the component and it can be used as a correctness reference to validate the system in a compositional manner. For that purpose, we have grounded our validation framework on testing techniques. We have presented compositional results relating the correctness of a system to the correctness of components. Based on these results, we have defined an incremental approach for testing from sequence diagrams.

Alumina é um material amplamente aplicado em diversas áreas. Uma dessas aplicações utiliza a alumina amorfa e a alumina gama, como suporte catalítico devido suas elevadas áreas de superfície específica e defeitos em suas estruturas cristalinas. Porém, problemas com a estabilidade das aluminas metaestáveis em altas temperaturas se tornaram um desafio. Assim a combinação da alumina com alguns óxidos emergiu como uma nova classe de materiais catalíticos com melhor estabilidade quando comparada com a alumina gama ou alumina amorfa convencional. Entretanto, entender como se dá à estabilização das fases através desses aditivos se tornou outro desafio. Assim, este trabalho teve como objetivo avaliar os possíveis efeitos de aditivos nas propriedades termodinâmicas da alumina. Além de sua influência sobre a transição de fases amorfo-gama, ou seja, a influência sobre o balanço energético através da evolução do tamanho de partícula. Para isto foram sintetizadas aluminas com diferentes concentrações de Mg2+ e Zr4+ através do método proposto por Pechini. As amostras foram calcinadas e caracterizadas por Calorimetria Diferencial de Varredura, Análise de Superfície Específica pelo método de Adsorção-Desorção de Gases, Difração de Raios X, Espectrometria de Infravermelho por Transformada de Fourier e Picnometria. Os resultados das análises mostraram um aumento da estabilidade para as amostras dopadas com os aditivos, porém com distintas evoluções de área de superfície específica, evidenciando que o caminho adotado pelo aditivo quando inserido em um material matriz independe de sua concentração. / Alumina is a material applied in several areas. One such application uses the gamma alumina and amorphous alumina as catalyst support. The use of alumina as the catalyst support is because of their high specific surface areas and defects in their crystal structures. However, problems with the stability of metastable aluminas at high temperatures have become a challenge. To solve this problem, we use a combination of some oxides to alumina improves the stability of the material when compared with conventional catalytic aluminas. However, a new challenge, to understand the performance of these oxides in the stabilization of alumina. This work aimed to evaluate the possible effects of additives on the thermodynamic properties of alumina, through its influence on the amorphous-phase transition range. The assessment of influence on the energy balance was made by the evolution of particle size. For this alumina powders were synthesized with different concentrations of Mg2+ and Zr4+ using the method proposed by Pechini. The samples were calcined and characterized by Differential Scanning Calorimetry, Surface Analysis by the method of Specific Adsorption-Desorption of Gases, X-Ray Diffraction, Infrared Spectroscopy Fourier Transform and Picnometry. The analysis results showed an increased stability for the samples doped with additives, but with different evolutions of specific surface area, showing the path taken by the additive when inserted into a matrix material depend on its concentration.

Il s’agit d’une étude interdisciplinaire – englobant essentiellement le théâtre, la psychologie et les neurosciences – dont le but est celui d’analyser le potentiel transformateur (et, d’une certaine manière, thérapeutique) inhérent à la pratique théâtrale. Ce travail se divise en deux axes centraux d’investigation : le premier se concentre sur le dialogue que le théâtre a entretenu avec les sciences de la vie au long de l’histoire de la civilisation occidentale tout en mettant en avant l’idée selon laquelle l’étude scientifique des émotions se présente comme le fil conducteur des échanges théorico-pratiques entre les arts scéniques et les sciences du vivant. Le deuxième axe de ce travail de recherche concerne les rapports entre les neurosciences contemporaines des émotions, le travail de l’acteur et les modifications que le l’expérience théâtrale peut opérer – surtout chez l’acteur – sur le plan ontologique. Dans ce travail de recherche, quelques notions neuroscientifiques qui s’avèrent fondamentales pour l’élaboration d’une approche neurobiologique du travail émotionnel de l’acteur ont été développées. Ce sont : la neuroplasticité, le système de neurones miroirs, le circuit cérébral du plaisir et l’utilisation consciente de la mémoire procédurale. / This is an interdisciplinary study – essentially encompassing theater, psychology and neuroscience – whose goal is to analyze the transforming (and, somehow, therapeutic) potential inherent to theater practice. This work is divided into two core areas of investigation: the first focuses on the dialogue that the theater has had with the life sciences throughout the history of Western civilization, highlighting the idea that the scientific study of emotions is presented as the main thread between theoretical and practical exchanges of the performing arts and life sciences. The second focus area of this research concerns the relationship between contemporary neuroscience of emotions, the work of the actor and the transformations that could occur through the theatrical experience – especially for the actor – on an ontological level. In this research, some neuroscientific concepts that prove fundamental to the development of a neurobiological approach to the emotional work of the actor have been developed. They are: neuroplasticity, the neuron mirror system, the brain gratification circuit and the conscious use of the procedural memory.

La thèse porte sur deux aciers emboutissables à chaud, soudés en configuration homogène ou hétérogène en termes de composition chimique et d'épaisseur. Les solutions en flans raboutés laser présentent en effet de remarquables performances à l'impact et connaissent un fort développement dans le contexte actuel de l'industrie automobile (réduction des émissions de CO2 et amélioration de la sécurité passive des véhicules). L'opération de soudage laser peut générer une hétérogénéité de la jonction soudée, due au mélange imparfait des deux matériaux et des conditions thermiques de solidification et d'emboutissage à chaud. Les propriétés mécaniques du joint soudé sont donc déterminées par la qualité du mélange, la composition chimique locale et le cycle thermique.La première partie de l'étude est consacrée à la quantification de l'hétérogénéité du joint soudé et la compréhension de la microstructure. Une nouvelle méthodologie a été développée pour étudier le comportement métallurgique et mécanique de ces joints hétérogènes, en élaborant des coulées synthétiques représentant les différentes compositions chimiques attendues dans le joint réel. Le comportement du joint soudé est reconstruit à partir des données obtenues par la caractérisation de ces coulées synthétiques. La deuxième partie de l'étude porte sur la compréhension de la formation de la microstructure de la zone fondue avant et après traitement thermomécanique simulant l'emboutissage à chaud. Des modèles quantitatifs ont été établis pour calculer les températures de changement de phase, les proportions relatives des constituants microstructuraux ainsi que la dureté de ces alliages en fonction de la composition chimique et du cycle thermique. La dernière partie de l'étude porte sur le comportement mécanique après traitement thermique. Des lois de comportement des matériaux synthétiques ont été déterminées en fonction de leur composition chimique et du cycle thermique. La sensibilité à la rupture fragile par clivage a été évaluée par des essais de traction sur éprouvettes sévèrement entaillées. Les lois de comportement obtenues ont été appliquées pour déterminer la tolérance du joint soudé à un défaut géométrique, sous sollicitation de traction uniaxiale. / This thesis is focused on the study of welded steel grades deformed by hot stamping. Typically, a laser welded blank is formed by butt joining two steel sheets, which can be identical or differ in chemical composition and/or sheet thickness. Such laser welded blank solution offers excellent crash performance, significant CO2 emission reduction and passive car safety thus it is of great interest for the automotive industry. The laser welding process may induce chemical and metallurgical heterogeneities arising from an incomplete mixture of the two base metals and from the thermal cycle conditions during welding and the subsequent heat treatment. The mechanical behaviour of the weld is therefore determined by the mixing quality, the chemical composition and the thermal cycle.The first part of the study aims at the quantification of the weld heterogeneity and the characterisation of the resulting microstructure. In this work, a new method is proposed to study the metallurgical and mechanical behaviour of those heterogeneous welds, by elaborating synthetic casted alloys representative of the different chemical compositions that can be locally found in the weld. The behaviour of the weld is then reconstructed from the results obtained from the characterisation of those synthetic casted alloys. The second part of the study concerns the understanding of the microstructure formation in the molten zone before and after a thermo-mechanical treatment which replicates the hot stamping conditions. Quantitative models have been established to calculate the phase transformation temperatures, the proportion of the principal constituents in the microstructure, and hardness of the weld as a function of chemical composition and thermal cycle parameters. The last part of the study is dedicated to the evaluation of the mechanical behaviour of the synthetic alloys after heat treatment. The constitutive material behaviour laws for each alloy have been identified. The sensitivity to brittle cleavage fracture has been assessed by tensile tests on severely notched bars. The constitutive material models are then applied to determine the sensitivity of the weld to geometrical defects under uniaxial loading.

No description available.

Images, in contrast to text, represent an effective and natural communication media for humans, due to their immediacy and the easy way to understand the image content. Shape recognition and pattern recognition are one of the most important tasks in the image processing. Crime scene photos should always be in focus and there should always be a ruler be present, this will allow the investigators the ability to resize the image to accurately reconstruct the scene. Therefore, the camera must be on a grounded platform such as tripod. Due to the rotation of the camera around the camera center there exist the distortion in the image which must be minimized. The distorted image should be corrected using transformation method. Deze taak is nogal uitdagend en essentieel omdat elke verandering in de afbeeldingen kan misidentificeren een object voor onderzoekers. Forensic image processing can help the analyst extract information from low quality, noisy image or geometrically distorted. Obviously, the desired information must be present in the image although it may not be apparent or visible. Considering challenges in complex forensic investigation, we understand the importance and sensitivity of data in a forensic images.The HT is an effective technique for detecting and finding the images within noise. It is a typical method to detect or segment geometry objects from images. Specifically, the straight-line detection case has been ingeniously exploited in several applications. The main advantage of the HT technique is that it is tolerant of gaps in feature boundary descriptions and is relatively unaffected by image noise. The HT and its extensions constitute a popular and robust method for extracting analytic curves. HT   attracted a lot of research efforts over the decades. The main motivations behind such interest are the noise immunity, the ability to deal with occlusion, and the expandability of the transform. Many variations of it have evolved. They cover a whole spectrum of shape detection from lines to irregular shapes. This master thesis presents a contribution in the field of forensic image processing. Two different approaches, Hough Line Transformation (HLT), Hough Circular Transformation (HCT) are followed to address this problem. Fout estimatie en validatie is gedaan met de hulp van root mean square method. De prestatie van beide methoden is geëvalueerd door ze te vergelijken. We present our solution as an application to the MATLAB environment, specifically designed to be used as a forensic tool for forensic images.