Notre travail s’intéresse aux maîtres d’apprentissage de l’enseignement supérieur et à la façon dont ils débutent dans cette fonction. En France, ceux qui occupent la mission de tuteur sont peu formés et les formations qui leurs sont proposées sont souvent de courte durée (1 journée). De même les prescriptions institutionnelles restent relativement floues, mentionnant peu le tuteur. Il semble dès lors que cette fonction s’apprenne très largement sur le tas. Notre objectif est ainsi de comprendre les pratiques formatives des tuteurs débutants et notamment, la façon dont les interactions et les relations que ces derniers vont voiravec d’autres acteurs (du monde scolaire, professionnel ou autre) vont les aider à construire leur pratique.Ce travail est construit à partir d’une enquête de terrain d’une année et d’un corpus caractérisé par une multiplicité de modes de production de données (observations participantes, captations audio et vidéo, entretiens, collecte de documents, etc.). Il prend la forme de trois études de cas dont le but est de comprendre comment se met en place une configuration tutorale (d’après Elias, 1981) et la façon dont cette configuration crée des affordances (Billett 1995, 2011), c’est à dire des opportunités d’apprentissage pour le tuteur débutant, dont il peut se saisir afin de construire sa pratique.Une analyse des prescriptions institutionnelles sur le tutorat et le rôle du maître d’apprentissage nous conduit à montrer que celui-ci occupe une place secondaire dans les discours institutionnels plutôt focalisés sur l’apprenti et adressés à ces derniers ou aux employeurs. De plus, les prescriptions se font à plusieurs niveaux (de la loi à l’école) et cela constitue un millefeuille de prescriptions qui restent floues et hétérogènes. Enfin, c’est une configuration tutorale relativement figée, incluant seulement trois acteurs (apprenti / MAP ou employeur / tuteur-école ou école) qui est la plupart du temps présentée.L’analyse de nos cas est réalisée en croisant deux niveaux : le niveau local et le niveau global. Il s’agit d’une part d’appréhender les interactions récurrentes et les relations qui se mettent en place dans le temps long et d’autre part, la façon dont les acteurs interagissent et se coordonnent dans des interactions et situations locales. Cela nous permet de documenter la façon dont une configuration tutorale émerge et se met en place dans le temps long, mais aussi la façon dont elle est localement consolidée ou au contraire bouleversée. Ces analyses nous permettent de mettre en avant que là où l’on a l’habitude de penser un duo tuteur-apprenti, il y a en réalité un réseau d’acteurs aux profils, objectifs et caractéristiques variés qui se crée dans le but d’accompagner l’apprenti. Cette configuration tutorale est dynamique et varie selon les contextes. Elle peut être constituée, outre l’apprenti et son tuteur, par des acteurs de la place de travail (hiérarchie, collègues, etc.), des acteurs de l’école (tuteurs-école, enseignants) ou encore des acteurs de la sphère familiale, amicale, etc. Chaque acteur de cette configuration a ses enjeux propres qui contribuent à orienter sa mise en place et son évolution dans le temps. Nos analyses montrent que cette évolution peut se faire en faveur de l’appropriation par le tuteur de son rôle. La configuration est, en effet, génératriced’affordances pour le maître d’apprentissage débutant, dont ce dernier peut se saisir afin de développer sa pratique tutorale. Ces affordances peuvent prendre des formes diverses (aide directe, inclusion à un collectif tutoral, échanges sur la pratique tutorale, etc.). Elles ne sont actualisées comme ressources que parce que le tuteur débutant s’en saisit, les rendant ainsi pertinentes pour sa pratique.Ces analyses nous conduisent à formuler des préconisations en vue d’améliorer la formation et l’information des tuteurs, notamment dans le cadre du travail d’ingénierie de formation actuellement mené par le CFA Formasup ARL. / This research focuses on workplace tutors in dual vocational tertiary courses, and how they begin in this role. In France some tutor’s training are offered but they are short-term (1 day) and few tutors participate. Institutional requirements remain vague with little mention mention of the workplace tutors. Therefore, it seems that a large part of tutors are learning this activity « on the job ». Our purpose is to understand how workplace tutors are learning their role, and in particular, how interactions and relationships they have with other actors (from the shool, the company, etc.) help them to build their practice of tutoring.This research is based on a one-year fieldwork and a corpus characterized by a multiplicity of data production modes (participating observations, audio and video recordings, interviews, document collection, etc.). It takes the form of three case studies whose aim is to understand how a tutorial configuration is set up (according to Elias, 1981) and how this configuration creates affordances (Billett 1995, 2011), i.e. learning opportunities for the novice workplace tutor, which he can take advantage of to build his practice.An analysis of the institutional requirements on tutoring and the role of the workplace tutor, leads us to show that he occupies a secondary place in speeches that are rather focused on the apprentice and addressed to them or to employers. In addition, this requirements are made at several levels (from law to school) and this constitutes a myriad (millefeuille) of requirements that remain vague and heterogeneous. Finally, it is a relatively fixed tutorial configuration, including only three actors (apprentice / MAP or employer / school-tutor or school) that is most of the time presented.The analysis of our cases is carried out by crossing two levels: the local level and the global level. On the one hand, it is a question of understanding the recurrent interactions and relationships that are established over time and, on the other hand, the way in which actors interact and coordinate themselves in local interactions and situations. This allows us to document how a tutorial configuration emerges and is implemented over time, but also how it is locally consolidated or disrupted. These analyses allow us to highlight that where we are used to thinking of a tutor-apprentice duo, there is in reality a network of actors with various profiles, objectives and characteristics that is created in order to support the apprentice. This tutorial configuration is dynamic and changes according to the context. It can be made up, in addition to the apprentice and his tutor, by actors in the workplace (hierarchy, colleagues, etc.), actors in the school (school-tutors, teachers) or actors in the family, friends, etc. Each actor in this configuration has its own purposes that contribute to orienting its implementation and evolution over time. Our analyses show that this evolution can be in favour of the tutor's appropriation of his role. The configuration is, in fact, agenerator of affordances for the novice workplace tutor, which he can take advantage of in order to develop his tutoring practice. These affordances can take various forms (direct support, inclusion in a tutoring collective, exchanges on tutoring practice, etc.). They are only actualized as resources because the novice tutor takes them over, making them relevant to his or her practice.In addition to documenting the training practices of tutors, this research aims to support the apprentices training center (Formasup ARL) in the engineering work of the training courses they are currently conducting.

Alors que l'informatique est résolument tournée vers l'avenir, cette thèse se concentre sur le passé ; non pas par nostalgie mais plutôt parce que le futur des logiciels âgés est une question d'actualité. Plus particulièrement trois thèmes sont abordés : la maintenance, la ré-ingénierie et la programmation globale. L'objectif de cette étude est d'explorer l'intersection entre la ré-ingénierie et la programmation globale, domaine que nous avons baptisé ré-ingénierie globale. L'idée principale est de réutiliser des concepts et des techniques de programmation détaillée. En fait nous proposons de définir la programmation globale en distinguant 4 aspects du logiciel : l'architecture, la manufacture, la variation et l'évolution. Un modèle abstrait basé sur des concepts ensemblistes est proposé pour modéliser les différentes entités de programmation globale. La technologie relative à ce domaine est ensuite décrite en considérant aussi bien l'état de l'art que l'état de la pratique. La différence entre ces deux aspects souligne l'intérêt de la ré-ingénierie globale. A titre d'illustration, nous étudions le cas des préprocesseurs en tant qu'outils de programmation globale. Ces outils de bas niveau provenant des années 70 sont traditionnellement utilisés pour décrire des familles de programmes. Pour faciliter la compréhension de tels artefacts nous proposons d'utiliser des techniques comme l'évaluation partielle, l'analyse inter-procédurale de flot de données ou encore le découpage. Ces techniques, définies de manière rigoureuse, s'appuient sur la sémantique dénotationnelle du préprocesseur utilisé. Un prototype montrant leur utilité a été réalisé. Il prouve qu'une approche basée sur des fondements théoriques issus de la programmation détaillée est applicable pour résoudre des problèmes pratiques de programmation globale.

Cable logging will become more important as harvesting shifts to greater annual proportions on steep terrain in New Zealand. The costs of cable logging are considerably higher than that of conventional ground-based methods. Improving cost-effectiveness has been identified as key to ensuring the forestry industry remains cost competitive in the international market. This thesis focuses on ways to better understand and improve cable logging methods by specifically focusing on rigging configurations. The investigation was conducted through a comprehensive literature review, an industry survey to establish current use and preferences, a Delphi survey with experts to establish actual advantages and disadvantages, scale model testing to establish some fundamental knowledge of tension to deflection relationship, and finally a series of targeted case studies to establish both productivity and skyline tension in actual operations. Each of these aspects of the research topic employed different methodology. The literature review highlighted the most relevant research relating to cable logging world-wide spanning nearly a century. Various research papers, manuals, books and computer software were summarized. While many aspects of cable yarding operations have been investigated, much of it focusing on various aspects of operational efficiency through case studies, there is very limited information with regard to rigging configurations. The survey of 50 cable logging practitioners determined what rigging configurations were commonly used in New Zealand. It includes their perceived advantages and disadvantages for varying levels of deflection, but also for specific scenarios such as pulling away from native forest boundaries and flying logs over a stream. Results showed that there were many conflicting perceptions about rigging configuration options. Using an expert panel, a Delphi process was used to derive consensus on what advantages were truly unique to each configuration. This allowed the longer lists of perceived advantages from the industry survey to be pared down to a concise list of ad/disadvantages that will be used in the updating of the Best Practice Guidelines for Cable Logging. To increase our fundamental understanding of tension / payload / deflection relationships, an experiment was conducted in a controlled environment. Using a model yarder in a lab and continuous tension and video recording devices, the dynamic skyline behavior of three similar configurations were tested: North Bend, South Bend and Block in the Bight. The tensions were compared by use of a two-way analysis of variance, which indicated configuration and choker length were significant variables in some but not all of the dynamic load tests. Results also showed that some configurations performed better than others in minimizing the shock loads due to dropping into full suspension, impact with ground objects, and breakout during bridling. Finally, a series of eight studies were conducted on targeted logging operations where relevant stand and terrain parameters were related to the continuous skyline tension monitoring, and recording of productivity through time study. The three targeted configurations included (1) North Bend, (2) Standing skyline using a motorized slack-pulling carriage and (3) a live skyline using a motorized grapple carriage. Results showed that peak and average tensions, as well as amplification factors and the payload to tension relationship, varied between configurations. The study also showed that tensions could be collected to compute measures of payload and tension efficiency, which provided insight into operational performance. The safe working load was exceeded in 53% of all cycles studied and across seven of eight study sites and 14 of 16 spans. Cycle times were significantly different between rigging configurations and that production information could be used to compute measures of labor and energy consumption as well as payload and tension efficiency; which also provide insight into operational performance. The industry should give serious consideration to the use of tension monitors. Tension monitors have many benefits and have the potential to improve cable logging operations in New Zealand. Monitoring tensions can help one learn new techniques or methods (i.e. rigging configurations), help improve payload analysis software for future planning and help evaluate new technology and machinery.

Notre thèse s’intéresse à la restructuration du service social d’une plate-forme téléphonique de santé – Santé Info. Au moment de l’étude le service social de ce centre de contact venait de faire l’objet d’une importante réorganisation, qui s’est concrétisée par la création d’une équipe de télé-opérateurs spécialisés. Dans ce contexte de changement organisationnel, notre travail vise à comprendre les incidences du développement de l’activité sur les pratiques situées des acteurs et saisir comment celles-ci nourrissent ce développement en retour. Nos réflexions autour de cette question sont inspirées par les théories de l’activité ainsi que les courants de la cognition et de l’action située. Nous nous appuyons sur la notion de perspective professionnelle et proposons la notion de saillance afin de rendre compte du développement de l’activité en pratique. Nous avons conduit une enquête ethnographique de près de deux ans au sein de cette organisation. Le dispositif méthodologique que nous avons mis en œuvre privilégie l’observation in situ des pratiques. La stratégie observationnelle choisie était celle du suivi, celui i) des acteurs, ii) des affaires c’est-à-dire des demandes traitées par plusieurs intervenants et iii) des situations de communication collective (formations, réunions d’équipe). Nous avons par ailleurs mobilisé la méthode de l’autoconfrontation à partir d’enregistrements audiovisuels. Nos résultats mettent en évidence deux axes de développement contradictoires de l’organisation, à savoir, d’une part, une tendance à l’intégration aux services des mutuelles fondatrices et une tendance à l’autonomisation de Santé Info en tant que prestataire de service externe. D’autre part, la restructuration du service social peut être appréhendée comme actualisant une contradiction sous-jacente au système d’activité, celle entre travail d’information (informer) et conseil (conseiller). Nous analysons les pratiques de prise et de construction de configurations d’indices informationnels des professionnels que nous qualifions de saillances. Nos analyses mettent en évidence que connaître son travail revient à connaître le travail des autres c’est-à-dire à anticiper leurs contraintes, leurs éventuelles difficultés, à reconnaître et tenir compte des impératifs auxquels ils doivent faire face (temporels et de production). La restructuration du service social de Santé Info au travers de la création d’une équipe spécialisée de téléconseillers – le pôle social - contribue à transformer ces pratiques. Par ailleurs, les nouvelles exigences que cette restructuration fait peser sur les professionnels participent de la redéfinition des enjeux de leurs actions en situation. En d’autres termes connaître le travail d’autrui est une ressource pour le collectif mais aussi pour le sujet. Les contributions de ce travail de thèse se situe à trois niveaux : théorique, méthodologique et disciplinaire. L’apport théorique réside dans la recherche d’une articulation entre une analyse orientée par les théories de l’activité et les approches situées de la cognition et de l’action. Ces questions nourrissent des enjeux méthodologiques pour notre travail, qui constituent le second apport de notre recherche. Il s’agit également de construire un dispositif d’observation et de collecte systématique de données dans un environnement professionnel exigeant où le travail est, à la fois, intellectuel et relationnel, la coopération latente et différée, et qui s’étayent sur une infrastructure sociotechnique complexe. Du point de vue de la psychologie du travail, notre étude ouvre à une réflexion autour des compétences collectives et du bien-être au travail. / Our research deals with the organizational change within Health Info, the inbound call center for a number of mutual health insurance companies. Health Info provides users with health information and referral for the purpose of helping them to make better choices in healthcare and to reduce their expenses. In order to improve the service delivered to the clients of the mutual insurance companies, call operators’ activity was redesigned. Some of the most experienced call center agents formed a new team (referred as the « social team »), which had the responsibility to process the information requests of users in need of financial support, different kind of allowances, within outbound calls. In this context, the goals of this doctoral thesis is to understand this organizational change as a development, that of Health Info’ collective activity but also that of the local individual practices. We build upon three approaches to the study of context - activity theory, situated action and situated cognition. Our research is based on a two years ethnographic study. We have used various data collection techniques. Those included ethnographic observation, video recordings of naturally occurring situations as well as interviews with staff members. We systematically attended and video recorded the regular staff meeting of the « social team ». We also shadowed staff members and followed specific « client cases » as first identified by call operators, then processed by the members of the « social team » and eventually transferred for further analysis to the social worker. Our results highlight several contradictions underlying Health Info’ current development. On one hand, Health Info is an additional service designed to fit within the those already existing of the mutual insurance companies. But it is also an autonomous service provider whose clients are the mutual companies. On the other hand, the « social team » reveals another contradiction between different work perspectives, namely that of informing users and helping them or providing them with support. Furthermore, our study underlines the practical dimensions of Health Info’ restructuring. The analysis of situated practices shows that works perspectives are grounded on salient configurations which are both emergent in situ and collectively elaborated cultural resources. The contributions of this doctoral thesis are to address some of the a) methodological and b) conceptual challenges arising from the use of activity theory as a theoretical framework in empirical studies, c) triggers off some interesting considerations on collective competencies and on well-being in the workplace.

O objetivo deste trabalho é descrever a estrutura das linhas axiais principais e médias de imersões de superfícies em R4 na vizinhança de pontos axiumbílicos. Pontos axiumbílicos são aqueles nos quais a elipse de curvatura se degenera em um círculo. Estudamos a perturbação dos ciclos axiais principais, e obtemos resultados sobre a genericidade dos ciclos axiais principais hiperbólicos e semi-hiperbólicos. / The aim of this work is to describe the structure of principal and mean axial lines of immersions of surfaces into R4, close to axiumbilic points. Axiumbilic points are those which the ellipse of curvature denegerate in a circle. We study the perturbation of principal axial cycles, and we obtain results about genericity of hyperbolic and semi-hyperbolic principal axial cycles.

Submitted by William Justo Figueiro (williamjf) on 2015-07-21T22:26:11Z No. of bitstreams: 1 62c.pdf: 1748478 bytes, checksum: 9f0a15323c00670499a429ed6941b16e (MD5) / Made available in DSpace on 2015-07-21T22:26:12Z (GMT). No. of bitstreams: 1 62c.pdf: 1748478 bytes, checksum: 9f0a15323c00670499a429ed6941b16e (MD5) Previous issue date: 2012-06 / Nenhuma / Esta dissertação de mestrado investiga a psicodinâmica da criança com sintomas emocionais e o funcionamento de sua família. O trabalho é apresentado através de dois artigos teórico-clínicos, constando dois estudos de casos documentais em cada um deles, criados a partir dos relatos da avaliação psicodiagnóstica e de atendimento psicoterápico com os pacientes/participantes. A primeira seção apresenta uma pesquisa realizada através do uso do psicodiagnóstico da criança porta-sintoma como dispositivo para o estudo e a prática da psicanálise vincular, na medida que se obtém dados sobre a psicodinâmica dos processos intersubjetivos, do sujeito e seu lugar no inconsciente grupal. A partir do estudo consciliente da psicanálise vincular, da lógica da complexidade de Morin e do terceiro incluído de Nicolescu, verificou-se que o psicodiagnóstico pode ser um exemplo de técnica interventiva que propicia a coleta de dados e compreensão do caso de forma complexa, bem como favorece o estabelecimento do vínculo dos pacientes com o profissional. Constatou-se também que a atividade pode também exercer uma função intermediária na escolha de modalidade de tratamento mais adequado e facilitar a participação da família que eventualmente possa apresentar resistência na aceitação do atendimento vincular. A segunda seção da dissertação compreende um artigo sobre o processo psicoterapêutico em que foi trabalhada a criação da demanda vincular, a partir da busca por atendimento individual da criança porta-sintoma. Os dois casos de atendimento em psicoterapia apresentados contemplam a análise psicodinâmica do sintoma das crianças com fatores indicadores do funcionamento familiar patológico. Através de um estudo de casos contrastantes, buscou-se compreender as características psicodinâmicas de duas famílias: a primeira, que aceitou a indicação da psicoterapia vincular, e a segunda, que recusou o atendimento em grupo. De modo geral, o trabalho possibilitou a reflexão a respeito da complexidade que o estudo e o trabalho psicanalítico exigem em relação aos diferentes processos de subjetivação presentes nas configurações familiares. / This dissertation investigates the psychodynamics of children with emotional symptoms and the functioning of their families. The work is presented through two theoretical and clinical articles, consisting in two case studies in each one of the papers. The case studies were taken from the records of the private practice of the researcher as a clinic psychologist and a child and family psychotherapist. The first section presents a study that shows the use of a child as symptom of the whole family. This kind of case can be used as a device for the study and practice of link psychoanalysis, in that is possible to obtain data about the psychodynamics of the intersubjective processes of the subject and his place in the unconscious group. From the link psychoanalysis point of view, the logic complexity of Morin and the third included Nicolescu, the psycho diagnostics assessment may be an example of interventional technique that provides data collection and understanding of cases so complexes, and it favors the establishment of the bond of the patients with the therapist. This activity may also play an intermediary role in choosing the most appropriate treatment modality, and to facilitate the participation of any family that can demonstrate resistance in the acceptance of family therapy. The second section of the dissertation includes an article on psychotherapeutic processes were the demand for link work was treated. The two cases presented in psychotherapy attendance include psychodynamic symptom analysis in children with pathological indicators of family functioning. We sought to understand the psychodynamic characteristics of the two families: the first one accepted the indication of link psychoanalysis, and the second one refused. In general, the work enabled the discussion about the complexity of psychoanalytic study and work required for the different processes of subjectivity present in family settings.

Made available in DSpace on 2014-07-29T16:25:13Z (GMT). No. of bitstreams: 1 Dissertacao Everton L L de Matos - pre textual.pdf: 210761 bytes, checksum: 94c893042cffcd3ee385dcb371a7c7c1 (MD5) Previous issue date: 2012-04-27 / The choro, he cultivates an instrumental genre improvisational style, has been transformed in the course of its history, both in melody and harmony. The first cries compounds possessed simple harmonies, making the soloists of the time to interpret differently from today. The different treatments harmonics, which have arisen over time, seem to have been one of the leaders of these different interpretations, which have been shown in an intense and characteristic improvisation. Apparently, there was an increase in these transformations of choro with the rapid development of technology and media from the mid-twentieth century. This circumstance, perhaps, brought a more intense and immediate contact of this musical genre with global genres such as jazz, for example, as a new and intense focus on improvisation, which has drawn attention to formal structures and performing hybrid performances. The intensification of cultivation of Jazz in the country and later the emergence of Bossa Nova in the mid-twentieth century, it seems, interfered markedly in the improvisation of gender, providing new composers to invest in new procedures related to this harmonic American genre. Given this circumstance, this study aimed to investigate the technical and cultural implications resulting from the interference of different harmonics in procedures related to the processes of improvisation and musical genre choro in this context not only seek melodic and harmonic innovations, but also processes of identity implicated in processes of cultural hybridization. / O choro, um gênero instrumental que cultiva o estilo improvisatório, sofreu transformações no decorrer da sua história, tanto na melodia, quanto na harmonia. Os primeiros choros compostos possuíam harmonias simples, fazendo que os solistas da época interpretassem de maneira diferente dos atuais. Os diferentes tratamentos harmônicos, que foram surgindo ao longo do tempo, parecem ter sido um dos principais responsáveis por essas interpretações distintas, que têm se evidenciado de forma intensa e característica na improvisação. Ao que tudo indica, houve um incremento nessas transformações do choro com o grande desenvolvimento da tecnologia e da mídia a partir de meados do século XX. Essa circunstância, possivelmente, trouxe um contato mais intenso e imediato desse gênero musical com gêneros globais, como o Jazz, por exemplo, assim como um novo e intenso foco na improvisação, o que tem apontado para estruturas formais e atuações performáticas híbridas. A intensificação do cultivo do Jazz no país e, posteriormente, o surgimento da Bossa Nova em meados do século XX, ao que tudo indica, interferiram de forma marcante na improvisação do gênero, propiciando aos novos compositores investirem em novos procedimentos harmônicos relacionados a esse gênero americano. Tendo em vista esta circunstância, esse trabalho teve como objetivo investigar as implicações técnicas e culturais resultantes da interferência de diferentes procedimentos harmônicos nos processos de improvisação relacionados ao gênero musical choro e, nesse contexto, buscar não apenas inovações melódicas e harmônicas, mas também processos identitários implicados com processos de hibridação cultural.

This work considers the synthesis of brass instrument sounds using time-domain numerical methods. The operation of such a brass instrument is as follows. The player's lips are set into motion by forcing air through them, which in turn creates a pressure disturbance in the instrument mouthpiece. These disturbances produce waves that propagate along the air column, here described using one spatial dimension, to set up a series of resonances that interact with the vibrating lips of the player. Accurate description of these resonances requires the inclusion of attenuation of the wave during propagation, due to the boundary layer effects in the tube, along with how sound radiates from the instrument. A musically interesting instrument must also be flexible in the control of the available resonances, achieved, for example, by the manipulation of valves in trumpet-like instruments. These features are incorporated into a synthesis framework that allows the user to design and play a virtual instrument. This is all achieved using the finite-difference time-domain method. Robustness of simulations is vital, so a global energy measure is employed, where possible, to ensure numerical stability of the algorithms. A new passive model of viscothermal losses is proposed using tools from electrical network theory. An embedded system is also presented that couples a one-dimensional tube to the three-dimensional wave equation to model sound radiation. Additional control of the instrument using a simple lip model as well a time varying valve model to modify the instrument resonances is presented and the range of the virtual instrument is explored. Looking towards extensions of this tool, three nonlinear propagation models are compared, and differences related to distortion and response to changing bore profiles are highlighted. A preliminary experimental investigation into the effects of partially open valve configurations is also performed.

In 2003 Cohn and Umans introduced a new group-theoretic framework for doing fast matrix multiplications, with several conjectures that would imply the matrix multiplication exponent $\omega$ is 2. Their methods have been used to match one of the fastest known algorithms by Coppersmith and Winograd, which runs in $O(n^{2.376})$ time and implies that $\omega \leq 2.376$. This thesis discusses the framework that Cohn and Umans came up with and presents some new results in constructing combinatorial objects called uniquely solvable puzzles that were introduced in a 2005 follow-up paper, and which play a crucial role in one of the $\omega = 2$ conjectures.

Cette thèse, ayant pour thème les algorithmes de la chimie quantique, s'inscrit dans le cade du changement de paradigme observé depuis une douzaines d'années, dans lequel les méthodes de calcul séquentielles se doivent d'être progressivement remplacées par des méthodes parallèles. En effet, l'augmentation de la fréquences des processeurs se heurtant à des barrières physiques difficilement franchissables, l'augmentation de la puissance de calcul se fait par l'augmentation du nombre d'unités de calcul. Toutefois, là où une augmentation de la fréquence conduisait mécaniquement à une exécution plus rapide d'un code, l'augmentation du nombre de cœurs peut se heurter à des barrières algorithmiques, qui peuvent nécessiter une adaptation ou un changement d'algorithme. Parmi les méthodes développées afin de contourner ce problème, on trouve en particulier celles de type Monte-Carlo (stochastiques), qui sont intrinsèquement "embarrassingly parallel", c'est à dire qu'elles sont par construction constituées d'une multitudes de tâches indépendantes, et de ce fait particulièrement adaptées aux architectures massivement parallèles. Elles ont également l'avantage, dans de nombreux cas, d'être capables de produire un résultat approché pour une fraction du coût calculatoire de l'équivalent déterministe exacte. Lors de cette thèse, des implémentations massivement parallèles de certains algorithmes déterministes de chimie quantique ont été réalisées. Il s'agit des algorithmes suivants : CIPSI, diagonalisation de Davidson, calcul de la perturbation au second ordre, shifted-Bk, et Coupled Cluster Multi Références. Pour certains, une composante stochastique a été introduite en vue d'améliorer leur efficacité. Toutes ces méthodes ont été implémentées sur un modèle de tâches distribuées en TCP, où un processus central distribue des tâches par le réseau et collecte les résultats. En d'autres termes, des nœuds esclaves peuvent être ajoutés au cours du calcul depuis n'importe quelle machine accessible depuis internet. L'efficacité parallèle des algorithmes implémentés dans cette thèse a été étudiée, et le programme a pu donner lieu à de nombreuses applications, notamment pour permettre d'obtenir des énergies de références pour des systèmes moléculaires difficiles. / This thesis, whose topic is quantum chemistry algorithms, is made in the context of the change in paradigm that has been going on for the last decade, in which the usual sequential algorithms are progressively replaced by parallel equivalents. Indeed, the increase in processors' frequency is challenged by physical barriers, so increase in computational power is achieved through increasing the number of cores. However, where an increase of frequency mechanically leads to a faster execution of a code, an increase in number of cores may be challenged by algorithmic barriers, which may require adapting of even changing the algorithm. Among methods developed to circumvent this issue, we find in particular Monte-Carlo methods (stochastic methods), which are intrinsically "embarrassingly parallel", meaning they are by design composed of a large number of independent tasks, and thus, particularly well-adapted to massively parallel architectures. In addition, they often are able to yield an approximate result for just a fraction of the cost of the equivalent deterministic, exact computation. During this thesis, massively parallel implementations of some deterministic quantum chemistry algorithms were realized. Those methods are: CIPSI, Davidson diagonalization, computation of second-order perturbation, shifted-Bk, Multi-Reference Coupled-Cluster. For some of these, a stochastic aspect was introduced in order to improve their efficiency. All of them were implemented on a distributed task model, with a central process distributing tasks and collecting results. In other words, slave nodes can be added during the computation from any location reachable through Internet. The efficiency for the implemented algorithms has been studied, and the code could give way to numerous applications, in particular to obtain reference energies for difficult molecular systems.