Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

La réalisation par des procédés robotisés de pièces composites à destination, notamment, de l’aéronautique vise à en augmenter la productivité. Cependant le Placement de Fibres Robotisé (PFR) est encore en phase de maturation et requiert de nombreux développements, en particulier dans le cas des composites à matrice thermoplastique ou à fibre sèche. Dans cette thèse, nous proposons différents outils qui permettent in fine de déterminer à l’avance la meilleure puissance de chauffe pour la mise en œuvre de ces composites. La difficulté réside dans le fait que cette puissance dépend de nombreux paramètres, non seulement au niveau de la matière utilisée (densité, chaleur spécifique. . .), mais encore au niveau du procédé lui-même (vitesse de déplacement, nombre et orientation des plis. . .). Nous avons construit un modèle réduit multi-paramétrique en utilisant la technique appelée Proper Generalised Decomposition (PGD). Les résultats ont été confrontés à ceux obtenus par des méthodes plus conventionnelles et aussi à des données expérimentales. / Realising composite parts mainly dedicated to aeronautics sector by robotised processes tends to increase productivity. However, Automated Tape Placement (ATP) is still in ripening stage and requires various developments, particularly in case of thermoplastic composites or dry fibres. In this manuscript, we propose different tools allowing to determine in advance the best heating power to drape composite fibres. Difficulty arises from dependence on many parameters, from material (density, specific heat) or from process itself (velocity, number and orientation of plies). Therefore we construct a multi-parametric reduced order model using the so called Proper Generalised Decomposition (PGD). Results have been faced to those obtained from more conventional methods but also to experimental data.

The objective of the thesis is to find appropriate methods for creation and classification of an investment project that should be created while using these methods. The variants drawn were: purchase of the investment by a bank loan, fincial leasing with 30% extra refund, distribution of finshed products by hiring transport or hiring the vehicles using operative leasing and discounted cash flow method. Hiring of the transport was found the most reasonable variant for the company. The purchase of own vehicles is disadvantageous.

Il semble maintenant établi que la majorité des étoiles se forment dans des amas (Carpenter 2000; Porras et al. 2003; Lada & Lada 2003). Comprendre l'origine et l'évolution des populations stellaires est donc l'un des plus grands défis de l'astrophysique moderne. Malheureusement, moins d'un dixième de ces amas restent gravitationellement liés au delà de quelques centaines de millions d'années (Lada & Lada 2003). L’étude des amas stellaires doit donc se faire avant leur dissolution dans la galaxie.Le projet Dynamical Analysis of Nearby Clusters (DANCe, Bouy et al. 2013), dont le travail fait partie, fournit le cadre scientifique pour l'analyse des amas proches et jeunes (NYC) dans le voisinage solaire. Les observations de l'amas ouvert des Pléiades par le projet DANCe offrent une opportunité parfaite pour le développement d'outils statistiques visant à analyser les premières phases de l'évolution des amas.L'outil statistique développé ici est un système intelligent probabiliste qui effectue une inférence bayésienne des paramètres régissant les fonctions de densité de probabilité (PDF) de la population de l'amas (PDFCP). Il a été testé avec les données photométriques et astrométriques des Pléiades du relevé DANCe. Pour éviter la subjectivité de ces choix des priors, le système intelligent les établit en utilisant l'approche hiérarchique bayésienne (BHM). Dans ce cas, les paramètres de ces distributions, qui sont également déduits des données, proviennent d'autres distributions de manière hiérarchique.Dans ce système intelligent BHM, les vraies valeurs du PDFCP sont spécifiées par des relations stochastiques et déterministes représentatives de notre connaissance des paramètres physiques de l'amas. Pour effectuer l'inférence paramétrique, la vraisemblance (compte tenu de ces valeurs réelles), tient en compte des propriétés de l'ensemble de données, en particulier son hétéroscédasticité et des objects avec des valeurs manquantes.Le BHM obtient les PDF postérieures des paramètres dans les PDFCP, en particulier celles des distributions spatiales, de mouvements propres et de luminosité, qui sont les objectifs scientifiques finaux du projet DANCe. Dans le BHM, chaque étoile du catalogue contribue aux PDF des paramètres de l'amas proportionnellement à sa probabilité d'appartenance. Ainsi, les PDFCP sont exempts de biais d'échantillonnage résultant de sélections tronquées au-dessus d'un seuil de probabilité défini plus ou moins arbitrairement.Comme produit additionnel, le BHM fournit également les PDF de la probabilité d'appartenance à l'amas pour chaque étoile du catalogue d'entrée, qui permettent d'identifier les membres probables de l'amas, et les contaminants probables du champ. La méthode a été testée avec succès sur des ensembles de données synthétiques (avec une aire sous la courbe ROC de 0,99), ce qui a permis d'estimer un taux de contamination pour les PDFCP de seulement 5,8 %.Ces nouvelles méthodes permettent d'obtenir et/ou de confirmer des résultats importants sur les propriétés astrophysiques de l'amas des Pléiades. Tout d'abord, le BHM a découvert 200 nouveaux candidats membres, qui représentent 10% de la population totale de l'amas. Les résultats sont en excellent accord (99,6% des 100 000 objets dans l'ensemble de données) avec les résultats précédents trouvés dans la littérature, ce qui fournit une validation externe importante de la méthode. Enfin, la distribution de masse des systèmes actuelle (PDSMD) est en général en bon accord avec les résultats précédents de Bouy et al. 2015, mais présente l'avantage inestimable d'avoir des incertitudes beaucoup plus robustes que celles des méthodes précédentes.Ainsi, en améliorant la modélisation de l'ensemble de données et en éliminant les restrictions inutiles ou les hypothèses simplificatrices, le nouveau système intelligent, développé et testé dans le présent travail, représente l'état de l'art pour l'analyse statistique des populations de NYC. / The origin and evolution of stellar populations is one of the greatest challenges in modern astrophysics. It is known that the majority of the stars has its origin in stellar clusters (Carpenter 2000; Porras et al. 2003; Lada & Lada 2003). However, only less than one tenth of these clusters remains bounded after the first few hundred million years (Lada & Lada 2003). Ergo, the understanding of the origin and evolution of stars demands meticulous analyses of stellar clusters in these crucial ages.The project Dynamical Analysis of Nearby Clusters (DANCe, Bouy et al. 2013), from which the present work is part of, provides the scientific framework for the analysis of Nearby Young Clusters (NYC) in the solar neighbourhood (< 500 pc). The DANCe carefully designed observations of the well known Pleiades cluster provide the perfect case study for the development and testing of statistical tools aiming at the analysis of the early phases of cluster evolution.The statistical tool developed here is a probabilistic intelligent system that performs Bayesian inference for the parameters governing the probability density functions (PDFs) of the cluster population (PDFCP). It has been benchmarked with the Pleiades photometric and astrometric data of the DANCe survey. As any Bayesian framework, it requires the setting up of priors. To avoid the subjectivity of these, the intelligent system establish them using the Bayesian Hierarchical Model (BHM) approach. In it, the parameters of prior distributions, which are also inferred from the data, are drawn from other distributions in a hierarchical way.In this BHM intelligent system, the true values of the PDFCP are specified by stochastic and deterministic relations representing the state of knowledge of the NYC. To perform the parametric inference, the likelihood of the data, given these true values, accounts for the properties of the data set, especially its heteroscedasticity and missing value objects. By properly accounting for these properties, the intelligent system: i) Increases the size of the data set, with respect to previous studies working exclusively on fully observed objects, and ii) Avoids biases associated to fully observed data sets, and restrictions to low-uncertainty objects (sigma-clipping procedures).The BHM returns the posterior PDFs of the parameters in the PDFCPs, particularly of the spatial, proper motions and luminosity distributions. In the BHM each object in the data set contributes to the PDFs of the parameters proportionally to its likelihood. Thus, the PDFCPs are free of biases resulting from typical high membership probability selections (sampling bias).As a by-product, the BHM also gives the PDFs of the cluster membership probability for each object in the data set. These PDFs together with an optimal probability classification threshold, which is obtained from synthetic data sets, allow the classification of objects into cluster and field populations. This by-product classifier shows excellent results when applied on synthetic data sets (with an area under the ROC curve of 0.99). From the analysis of synthetic data sets, the expected value of the contamination rate for the PDFCPs is 5.8 ± 0.2%.The following are the most important astrophysical results of the BHM applied tothe Pleiades cluster. First, used as a classifier, it finds ∼ 200 new candidate members, representing 10% new discoveries. Nevertheless, it shows outstanding agreement (99.6% of the 105 objects in the data set) with previous results from the literature. Second, the derived present day system mass distribution (PDSMD) is in general agreement with the previous results of Bouy et al. (2015).Thus, by better modelling the data set and eliminating unnecessary restrictions to it, the new intelligent system, developed and tested in the present work, represents the state of the art for the statistical analysis of NYC populations.

In this article, the author stresses the importance of the right to proper motivation in the context of administrative procedures. In that sense, he states that all public bodies are required to issue administrative acts duly substantiated, because this is a requirement which, if unobserved, generates the nullity of the act. But beyond to validate administrative act, the author argues that the main benefit of meeting the proper motivation lies in the improvement of the interaction between the taxpayers and the Public Administration, generating greater confidence in state activity and promoting the development of economic activities with increasing levels of formality. / En el presente artículo, el autor destaca la importancia del principio-derecho a la debida motivación en el marco de los procedimientos administrativos. En esa línea, afirma que todas las entidades públicas están obligadas a expedir actos administrativos debidamente fundamentados, pues este constituye un requisito de validez que, de ser inobservado, acarrea la nulidad del acto. Pero más allá de validar al acto administrativo, el autor sostiene que el principal beneficio de que se cumpla con la debida motivación radica en la mejora de la interacción entre los administrados y la Administración Pública, generando mayor confianza en la actividad estatal y propiciando el desarrollo de actividades económicas con cada vez mayores niveles de formalidad.

Représentations séparées pour la simulation multi-échelle du comportementmécanique et de l’endommagement des matériaux composites.Résumé: Le développement de méthodes numériques performantes pour simuler les structurescomposites est un défi en raison de la nature multi-échelle et de la complexité des mécanismed’endommagement de ce type de matériaux. Les techniques classiques de discrétisationvolumique conduisent à des coûts de calcul importants et sont restreintes en pratique à despetites structures.Dans cette thèse, un nouvelle stratégie basée sur une représentation séparée de la solution estexplorée. L’objectif est de proposer un cadre numérique efficace et fiable pour analyser les endommagementsdans les composites stratifiés sous chargements statiques et dynamiques. Ladécomposition propre généralisée (PGD) est utilisée pour construire la solution.Pour traiter l’endommagement, et plus particulière le délaminage, un modèle de zone cohésivea été implémenté dans la PGD. Une approches multi-échelle innovante est également proposéepour simuler le comportement mécanique des composites à microstructure périodique. L’idéeprincipale est de séparer deux échelles : l’échelle du motif périodique (microstructure) et l’échellemacroscopique. Les résultats de la PGD sont très proches des résultats obtenus par la méthodeéléments fini classique. Finalement, la PGD permet de réduire significativement la complexitédes modèles tout en gardant une précision satisfaisante. / Separated representations for the multiscale simulation of the mechanicalbehavior and damages of composite materials.Abstract: The development of efficient simulations for composite structures is very challengingdue to the multiscale nature and the complex damage process of this materials. When usingstandard 3D discretization techniques with advanced models for large structures, the computationalcosts are generally prohibitive.In this thesis, a new strategy based on a separated represenation of the solution is explored todevelop a computationally efficient and reliable numerical framework for the analysis of damagesin laminated composites subjected to quasi-static and dynamic loading. The PGD (Proper GeneralizedDecomposition) is used to build the solution.To treat damage, and especially delamination, a cohesive zone model has been implemented inthe PGD solver. A novel multiscale approach is also proposed to compute the mechanical behaviorof composites with periodic microstructure. The idea is to separate two scales: the scaleof periodic pattern and the macroscopic scale. The PGD results have been compared with theresults obtained with the classcial finite element method. A close agreement is found between thetwo approach and the PGD has significantly reduced the model complexity.

O presente estudo versa sobre a conduta de administradores e controladores em contexto oferta hostil, tendo como principal objetivo a análise desta à luz do interesse social e dos deveres fiduciários, buscando, ao fim, comprovar que o Brasil possui um arcabouço legislativo apto a regular tais situações, bem como que a experiência norteamericana pode servir como fator de auxílio na investigação do papel desses sujeitos no referido contexto. / This paper deals with the behavior of managers and controlling shareholders in hostile tender offer context, with the main goal of analyse it in the light of the “proper role of the companies” and the fiduciary duties, aiming, finally, to prove that Brazilian law is able to rule those situations, as well that American experience could serve as a helpful instrument in the search for directors and officers “proper role” in the related situations.

Prior to 1994, the South African Health Department was characterised by a fragmented health care system, which was largely curative and hospital based, with services planned and managed without community involvement and participation. The government, through the establishment of a district health system, integrated the health services with the aim of overcoming the fragmentation, and providing integrated comprehensive health care services that are equitable, accessible, efficient and effective. The integration of health services in Gauteng, meant the devolution of primary health care services from the provincial health department to the local authority health department, because the local authority services are nearer and accountable to the community. The process of integration of health services also meant the closing down of provincial clinics and transferring of provincial authority nurses to the local authority clinics. The transfer process impacted negatively on staff morale and on the resources available for health care delivery to the communities. It is against this background that the researcher decided to investigate the integration process. The researcher then conducted focus group interviews with the local authority nurses, provincial authority nurses and the district management team as these nurses's immediate supervisors. The results revealed that the local and provincial authority nurses were integrated without proper consultation and as a result integration was rejected. The following themes emerged from the results as negative perceptions and obstacles towards integration: lack of consultation, disparities in conditions of service and resistance to change. Positive perceptions also emerged from the results as strategies to improve the integration, and these strategies were used to develop guidelines to operationalise the model. It is envisaged that the proposed model will serve as a theoretical framework for nurse managers from both spheres of government, local and provincial to improve the integration of nurses through proper consultation, and involvement of nurses in the process affecting them. It is further envisaged that the model will serve as guideline to introduce changes within the district health system with more understanding and acceptance by nurses affected. Health care managers will find the model useful to overcome disparities in conditions of service among nurses and, in turn this may boost the moral of nurses and lead to successful integration of provincial and local authority nurses. / Health Studies / D.Litt. et Phil (Health Studies)

Variable Valve Timing (VVT) presents a powerful tool in the relentless pursuit of efficiency improvements in the internal combustion engine. As the valves have such ultimate control over the gas exchange processes, extensive research effort in this area has shown how valve event timing can be manipulated to reduce engine pumping losses, fuel consumption and engine out emissions. Pumping losses may be significantly reduced by use of throttleless strategies, making use of intake valve duration for load control, while alternative cycles such as the Miller cycle allow modification of the effective compression ratio. More recently, the value of single valve operation in part load conditions is exploited, bringing with it the concept of asymmetric valve lifts. Work in this area found the side effect of asymmetric valve operation is a significant change in the behaviour of the in-cylinder flow structures, velocities and turbulence intensity. Work presented in this thesis exploits asymmetric valve strategies to modify the in-cylinder flow conditions. The Proper Orthogonal Decomposition (POD) is a method employed in the fluids dynamics field to facilitate the separation of coherent motion structures from the turbulence. In the presented work, the application of POD to in-cylinder flow analysis is further developed by the introduction of a novel method for identifying the POD modes representative of coherent motion and those representative of the turbulence. A POD mode correlation based technique is introduced and developed, with the resulting fields showing evidence of coherence and turbulence respectively. Experimental tests are carried out using a full length optically accessible, single cylinder research engine equipped with a fully variable valve train (FVVT) to allow full control of both valve timing and lift. In-cylinder flow is measured through the use of Particle Image Velocimetry (PIV) at several crank angle timings during the intake stroke whilst the engine is operated under a range of asymmetric valve strategies. The exhaust valves and one intake valve have their respective schedules fixed, while the second intake valve schedule is adjusted to 80\%, 60\%, 40\%, 20\%, 0\% lift. The resulting PIV fields are separated into coherent motion and turbulence using the developed technique, allowing for analysis of each constituent independently. The coherent element gives insight to large scale flows, often of the order of magnitude of the cylinder. These structures not only give a clear indication of the overall motion and allow assessment of flow characteristics such as swirl and tumble ratio, but the variation in the spatial location of these structures provides additional insight to the cyclic to cycle variation (CCV) of the flow, which would not otherwise be possible due to the inclusion of the turbulent data. Similarly, with the cyclic variation removed from the turbulent velocity field, a true account of the fluctuating velocity, u' and derived values such as the Turbulent Kinetic Energy (TKE) may be gained. Results show how manipulation of a one intake valve timing can influence both the large scale motions and the turbulence intensity. By the reduction of lift, the swirl ratio is increased almost linearly as the typical counter-rotating vortex pair becomes asymmetric, before a single vortex structure is observed in the lowest lift cases. A switching mechanism between the two is identified and found to be responsible for increased levels of CCV. With the reduction in lift, TKE is observed not only to increase, but change the spatial distribution of turbulence. Of course, the reduction in valve lift comes with the penalty of a reduced valve curtain area. However, it was identified both in literature and throughout this study that the reduction in lift did not negatively influence the engine breathing as the same trapped mass was achieved under all cases with no adjustment of manifold pressure. While literature shows both bulk motion and turbulence are key in liquid fuel break-up during the intake stroke, the mixing effects under port-injected natural gas were investigated experimentally using Laser Induced Fluorescence (LIF). The valve strategy was found to have no significant effect on the mixture distribution at the time of spark.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Qual é o Objeto Próprio do Ensino Religioso escolar? Esta é a questão central desta tese. Dela derivam os seguintes problemas corolários: Qual é a compreensão e a fundamentação teórico-epistemológica de docentes e pesquisadores da área concernente a este objeto? O que dizem os Parâmetros Curriculares Nacionais para o Ensino Religioso (PCNER) a este respeito? Que abordagens atinentes podem ser encontradas nas publicações em eventos representativos na área? O que pode ser encontrado sobre o tema nos dois espaços online mais representativos do Ensino Religioso no país: o site do Fórum Nacional Permanente do Ensino Religioso (FONAPER) e o site do Grupo de Pesquisa Educação e Religião (GPER)? Para tentar responder a questão central da pesquisa e oferecer aportes epistemológicos para o Ensino Religioso, a tese está dividida em duas partes. Na primeira é oferecida uma análise epistemológica do Ensino Religioso. Esta começa com a exposição da identidade do autor como base para a leitura e para a construção do argumento. O segundo capítulo trata mais especificamente da sondagem da concepção atual do que seja este objeto. Para tal, foi feita análise de pesquisa de campo com docentes e pesquisadores da área; análise dos PCNER; do livro de visitas do site do FONAPER; dos temas das teses, dissertações e monografias postadas no site do GPER; de publicações em eventos; e do Caderno Pedagógico de Ensino Religioso do Estado do Paraná. Na segunda parte da tese, para as proposições epistemológicas, começa-se com a conceituação do fenômeno religioso e da pesquisa de abordagem fenomenológica; no segundo capítulo procura-se ofertar subsídios para a reflexão a respeito do sagrado como numinoso em Rudolf Otto e do Sagrado de Atribuição como um sistema de significações. Numa reflexão dentro da mesma perspectiva articula-se o mito a partir das rubricas etimológica, antropológica e literária. No último capítulo trata-se da transcendência em seus aspectos ontológico-culturais, em sua relação com a imanência, com o objeto de transcendência, com os meios de transcendência, com a educação e, mais especificamente, com a pedagogia de Paulo Freire. / What is the proper object of Religious Education in school? This is the main question of this thesis, from which the following corollary problems derive: What is the comprehension and the theoretical-epistemological foundation of professors and researchers in the area concerning this object? What do the National Curriculum Guidelines for Religious Education (PCNER) state as regards this subject? What relevant approaches can be found in publications in this areas representative events? What can be found on this subject in the countrys two most representative religious education online venues: the National Permanent Forum of Religious Educations (FONAPER) website and the Education and Religion Research Groups (GPER) website? In order to answer the main question of this research and offer epistemological input for Religious Education, the thesis is divided into two parts. In the first, an epistemological analysis of Religious Education is offered. It begins with exposure of the authors identity as a basis for reading and for the construction of the argument. The second chapter deals more specifically with the assessment of the current concept of what this object is. For this purpose, a field research analysis was carried out with professors and researchers in the area; analysis of the PCNER; of FONAPERs website guest book; of the topics of theses, dissertations and monographs posted on GPERs website; of the publications in events; and of the Pedagogical Book of Religious Education of the State of Paraná. The second part of the thesis, for the epistemological propositions, begins with the concept of religious phenomenon and the research of phenomenological approach; the second chapter seeks to offer subsidies for reflection as regards the sacred as numinous in Rudolf Otto and the Sacred of Attribution as a system of meanings. A reflection within the same perspective articulates the myth from the etymological, anthropological and literary rubric. In the last chapter, transcendence is dealt with in its ontological and cultural aspects, in its relation with the immanence, with the object of transcendence, with the means of transcendence, with education and, more specifically, with Paulo Freires pedagogy.