This research work investigates the thermal performance of a film-cooled gas turbine endwall under two different mainstream flow conditions. In the first part of the research investigation, the effect of unsteady passing wakes on a film-cooled pitchwise-curved surface (representing an endwall without airfoils) was experimentally studied for heat transfer characteristics on a time-averaged basis. The temperature sensitive paint technique was used to obtain the local temperatures on the test surface. The required heat flux input was provided using foil heaters. Discrete film injection was implemented on the test surface using cylindrical holes with a streamwise inclination angle of 35? and no compound angle relative to the mean approach velocity vector. The passing wakes increased the heat transfer coefficients at both the wake passing frequencies that were experimented. Due to the increasing film cooling jet turbulence and strong jet-mainstream interaction at higher blowing ratios, the heat transfer coefficients were amplified. A combination of film injection and unsteady passing wakes resulted in a maximum pitch-averaged and centerline heat transfer augmentation of ? 28% and 31.7% relative to the no wake and no film injection case. The second part of the research study involves an experimental and numerical analysis of secondary flow and coolant film interaction in a high subsonic annular cascade with a maximum isentropic throat Mach number of ? 0.68. Endwall (platform) thermal protection is provided using discrete cylindrical holes with a streamwise inclination angle of 30? and no compound angle relative to the mean approach velocity vector. The surface flow visualization on the inner endwall provided the location of the saddle point and the three-dimensional separation lines. Computational predictions showed that the leading-edge horseshoe vortex was confined to approximately 1.5% of the airfoil span for the no film injection case and intensified with low momentum film injection. At the highest blowing ratio, the film cooling jet weakened the horseshoe vortex at the leading-edge plane. The passage vortex was intensified with coolant injection at all blowing ratios. It was seen that increasing average blowing ratio improved the film effectiveness on the endwall. The discharge coefficients calculated for each film cooling hole indicated significant non-uniformity in the coolant discharge at lower blowing ratios and the strong dependence of discharge coefficients on the mainstream static pressure and the location of three-dimensional separation lines. Near the airfoil suction side, a region of coalesced film cooling jets providing close to uniform film coverage was observed, indicative of the mainstream acceleration and the influence of three-dimensional separation lines.

No description available.

The passive components such as inductors and capacitors are bulky parts on circuit boards. Researchers in academia, government, and industry have been searching for ways to improve the magnetic energy density and reduce the package size of magnetic parts. The "constant-flux" concept discussed herein is leveraged to achieve high magnetic-energy density by distributing the magnetic flux uniformly, leading to inductor geometries with a volume significantly lower than that of conventional products. A relatively constant flux distribution is advantageous not only from the density standpoint, but also from the thermal standpoint via the reduction of hot spots, and from the reliability standpoint via the suppression of flux crowding. For toroidal inductors, adding concentric toroidal cells of magnetic material and distributing the windings properly can successfully make the flux density distribution uniform and thus significantly improve the power density. Compared with a conventional toroidal inductor, the constant-flux inductor introduced herein has an enclosed-winding geometry. The winding layout inside the core is configured to distribute the magnetic flux relatively uniformly throughout the magnetic volume to obtain a higher energy density and smaller package volume than those of a conventional toroidal inductor. Techniques to shape the core and to distribute the winding turns to form a desirable field profile is described for one class of magnetic geometries with the winding enclosed by the core. For a given set of input parameters such as the inductor's footprint and thickness, permeability of the magnetic material, maximum permissible magnetic flux density for the allowed core loss, and current rating, the winding geometry can be designed and optimized to achieve the highest time constant, which is the inductance divided by resistance (L/Rdc). The design procedure is delineated for the constant-flux inductor design together with an example with three winding windows, an inductance of 1.6 µH, and a resistance of 7 mΩ. The constant-flux inductor designed has the same inductance, dc resistance, and footprint area as a commercial counterpart, but half the height. The uniformity factor α is defined to reflect the uniformity level inside the core volume. For each given magnetic material and given volume, an optimal uniformity factor exists, which has the highest time constant. The time constant varies with the footprint area, inductor thickness, relative permeability of the magnetic material, and uniformity factor. Therefore, the objective for the constant-flux inductor design is to seek the highest possible time constant, so that the constant-flux inductor gives a higher inductance or lower resistance than commercial products of the same volume. The calculated time-constant-density of the constant-flux inductor designed is 4008 s/m3, which is more than two times larger than the 1463 s/m3 of a commercial product. To validate the concept of constant-flux inductor, various ways of fabrication for the core and the winding were explored in the lab, including the routing process, lasing process on the core, etching technique on copper, and screen printing with silver paste. The most successful results were obtained from the routing process on both the core and the winding. The core from Micrometals has a relative permeability of around 22, and the winding is made of copper sheets 0.5 mm thick. The fabricated inductor prototype shows a significant improvement in energy density: at the same inductance and resistance, the volume of the constant-flux inductor is two times smaller than that of the commercial counterpart. The constant-flux inductor shows great improvement in energy density and the shrinking of the total size of the inductor below that of the commercial products. Reducing the volume of the magnetic component is beneficial to most power. The study of the constant-flux inductor is currently focused on the dc analysis, and the ac analysis is the next step in the research. / Master of Science

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

Cette thèse apporte des solutions théoriques et pratiques à deux problèmes soulevés par la photographie numérique en présence de mouvement, et par la photographie infrarouge. La photographie d'objets en mouvement semblait ne pouvoir se faire qu'avec des temps d'exposition très courts, jusqu'à ce que deux travaux révolutionnaires proposent deux nouveaux types de caméra permettant un temps d'exposition arbitraire. Le flutter shutter de Agrawal et al. crée en effet un flou inversible, grâce à un obturateur aux séquences d'ouverture-fermeture bie{\it n choisies. Le motion invariant photography de Levin et al. obtient ce même effet avec une accélération constante de la caméra. Les deux méthodes suivent ainsi un nouveau paradigme, la computational photography, selon lequel les caméras sont repensées, car elles incluent un traitement numérique sophistiqué. Cette thèse propose une méthode pour évaluer la qualité image des nouvelles caméras. Le fil conducteur de l'analyse est donc l'évaluation du SNR (signal to noise ratio) de l'image obtenue après déconvolution. La théorie fournit des formules explicites pour le SNR, soulève deux paradoxes de ces caméras, et les résout. Elle permet d'obtenir le modèle de mouvement sous-jacent à chaque flutter shutter, notamment tous ceux qui sont brevetés. Une seconde partie plus brève aborde le problème de qualité principal en imagerie vidéo infrarouge, la non-uniformité. Il s'agit d'un bruit évolutif et structuré en colonnes causé par le capteur. La conclusion des travaux est qu'il est non seulement possible mais également efficace et robuste d'effectuer la correction sur une seule image. Cela permet de contourner le problème récurrent des "ghost artifacts"résultant d'une incohérence du traitement par rapport au modèle d'acquisition. / This thesis provides theoretical and practical solutions to two problems raised by digital photography of moving scenes, and infrared photography. Until recently photographing moving objects could only be done using short exposure times. Yet, two recent groundbreaking works have proposed two new designs of camera allowing arbitrary exposure times. The flutter shutter of Agrawal et al. creates an invertible motion blur by using a clever shutter technique to interrupt the photon flux during the exposure time according to a well chosen binary sequence. The motion-invariant photography of Levin et al. gets the same result by accelerating the camera at a constant rate. Both methods follow computational photography as a new paradigm. The conception of cameras is rethought to include sophisticated digital processing. This thesis proposes a method for evaluating the image quality of these new cameras. The leitmotiv of the analysis is the SNR (signal to noise ratio) of the image after deconvolution. It gives the efficiency of these new camera design in terms of image quality. The theory provides explicit formulas for the SNR. It raises two paradoxes of these cameras, and resolves them. It provides the underlying motion model of each flutter shutter, including patented ones. A shorter second part addresses the the main quality problem in infrared video imaging, the non-uniformity. This perturbation is a time-dependent noise caused by the infrared sensor, structured in columns. The conclusion of this work is that it is not only possible but also efficient and robust to perform the correction on a single image. This permits to ensure the absence of ``ghost artifacts'', a classic of the literature on the subject, coming from inadequate processing relative to the acquisition model.

Cette étude est consacrée au droit privé fédéral et à l'interaction entre la législation fédérale et le droit privé des provinces. Elle porte plus précisément sur le rôle des tribunaux dans le cadre de cette interaction. Elle a pour objectif de vérifier comment les juges procèdent à l'unification du droit privé fédéral en évitant de recourir formellement au droit provincial à titre supplétif. Dans un premier temps, elle établit le cadre juridique gouvernant l'interprétation du droit privé fédéral, de même que l'exercice du pouvoir judiciaire dans ce contexte. Dans un deuxième temps, elle analyse à travers un ensemble de jugements les procédés employés par les juges pour réaliser l'unification du droit privé fédéral. Elle conclut que ces procédés peuvent effectivement permettre de réaliser, au plan pratique, une telle unification. Cependant, ces interventions judiciaires sont ponctuelles et sont limitées à certains aspects de la conception ou de l'application des normes de droit privé. Dans les cas plus problématiques, elles peuvent avoir pour effet soit de nier le vide normatif rendant nécessaire le recours aux sources supplétives provinciales, soit de nier la pluralité formelle de ces sources dans le contexte fédéral. / This study is devoted to federal private law and the interaction between federal legislation and provincial private law. In particular, it is devoted to the role of the courts in such interaction. Hs objective is to assess how judges proceed with the unification of federal private law by avoiding formal reference to provincial law to supplement federal legislation. Firstly, the study considers the legal framework governing the interpretation of federal private law, as well as the exercise of judicial power in this context. Secondly, the study reviews means employed by judges, through a series of judgments, to proceed with the unification of federal private law. The study concludes that unification can effectively be achieved through such means. However, these judicial interventions are limited to sorne aspects of the elaboration and application ofprivate norms. In more complex cases, the effect of these interventions may be to disregard normative gaps that make necessary to supplement federal legislation with sources of provincial law, or to deny the plurality of these sources in the federal context. / "Mémoire présenté à la Faculté des études supérieures en vue de l'obtention du grade de maîtrise en droit". Ce mémoire a été accepté à l'unanimité et classé parmi les 5% des mémoires de la discipline. Commentaires du jury : "Remarquable par le choix du sujet et son traitement tant pour la forme que le fond. Mérite publication".

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

The aim of this essay is to provide an answer to the question "What is the Meaning of Meaningless sex in Dystopia?". It will show that meaningful concepts such as sexual satisfaction, pleassure, passion, love, bonding, procreation and family are handled as threats in dystopian societies described in well-known novels as We, Brave New World and Nineteen Eighty-Four . It will explain how the conflict between the collective and the individual influences peoples' sexuality. It will also show how leading powers in the three dystopian societies use different methods to remove the significanse and functions of sex. It will suggest meaningless sex is a means to control the masses in a collective and that meaningful sex is an act of rebelion against the state. / .

The objective of this work was to evaluate the influence of the fruit maturation stage in the physical attributes and germination of Schefflera morototoni pyrenes subjected to pre-germination treatments. Fruits with green and purplish green coloration were collected from 14 individuals, pulped in running water, the hollow pyrenes were discarded after counting, together with those presenting retracted and oxidized endosperm, using the uniforms (with the greenish endosperm occupying the whole cavity of the pyrene). The experiment was conducted in completely randomized design in a 2 x 5 factorial (stages of fruit maturation and pre-germination treatments), with four repetitions in plots containing 25 pyrenes. For greater capacity and germination speed of the pyrenes, fruits should be harvested when they present a purplish green coloration, discarding those with hollow pyrenes, with retracted or oxidized endosperm. The germination capacity of the pyrenes with uniform endosperm varied between 50 and 60%, with the beginning of the process at about 40 days after sowing and extending for up to 60 days in vermiculite. Pulped pyrenes, dried and soaked in water at 60ºC for 5 minutes, followed by soaking in water at room temperature for 12 hours begin the germination process in less time, in relation to those pulped, dried, scarified and soaked for 6 hours. The fruit endocarp is permeable and rigid; however, it presents a natural opening when soaked. The objective was to evaluate the variability in seedling emergence measures of Schefflera morototoni from pyrenes of different individuals. Fruits of 14 individuals were pulped and pyrenes with uniform endosperm were selected. The experiment was conducted in completely randomized design with 14 treatments (individuals) and 11 repetitions in parcels containing 50 pyrenes with uniform endosperm treated by immersion in water at 60 ºC for 5 minutes and then soaked at room temperature for 12 hours. The substrate used was a mixture in proportion 2:1:1:1/2 (v/v) soil, commercial substrate Bioplant®, coarse sand and vermicompost, with pyrenes sown at 1 cm depth in expanded polystyrene trays, maintained in a nursery with 50% reduction in luminosity at average temperatures of 19.3ºC minimum and 30.2 ºC maximum and daily irrigation. Daily counting of seedlings evaluated capacity, time, rate, uniformity and synchrony of emergence, besides the distribution of frequency of emergence in relation to time. The emergence of seedlings is slow, irregular and asynchronous, taking more than 80 days for stabilization of the emergence. The percentage of seedlings can reach up to 57%, but even when the endosperm occupies the whole cavity of the pyrene and is greenish, the emergence of seedlings may not occur. There is variability in seedling emergence measurements from pyrenes of different Schefflera morototoni individuals. / CAPÍTULO II: O objetivo do trabalho foi avaliar a influência do estádio de maturação dos frutos nos atributos físicos e de germinação de pirênios de Schefflera morototoni submetidos a tratamentos pré-germinativos. Frutos com coloração verde e verde-arroxeada foram coletados de 14 indivíduos, despolpados em água corrente, descartando-se, após contabilização, os pirênios chochos, com endosperma retraído e oxidado, utilizando-se os uniformes (com endosperma esverdeado ocupando toda a cavidade do pirênio). O delineamento experimental foi o inteiramente casualizado em esquema fatorial 2 x 5 (estádios de maturação dos frutos e tratamentos pré-germinativos), com quatro repetições em parcelas contendo 25 pirênios. Verificou-se que para maior capacidade e velocidade de germinação dos pirênios, os frutos devem ser colhidos quando apresentarem coloração verde-arroxeada, descartando-se àqueles com pirênios chochos, endosperma retraído ou oxidado. A capacidade de germinação dos pirênios com endosperma uniforme varia entre 50 e 60%, com início do processo em cerca de 40 dias após semeadura, se estendendo por até 60 dias em vermiculita. Pirênios despolpados, secos e embebidos em água a 60oC por 5 minutos, seguida da embebição em água à temperatura ambiente por 12 horas iniciam o processo de germinação em menor tempo, em relação aos despolpados, secos, escarificados e embebidos por 6 horas. O endocarpo dos frutos é permeável e rígido, no entanto, apresenta abertura natural quando embebido. CAPÍTULO III: O objetivo foi avaliar a variabilidade nas medidas de emergência de plântulas de Schefflera morototoni provenientes de pirênios de diferentes indivíduos. Frutos de 14 indivíduos foram despolpados, selecionando-se pirênios com endosperma uniforme. O experimento de emergência foi conduzido em delineamento inteiramente casualizado com 14 tratamentos (indivíduos) e 11 repetições em parcelas contendo 50 pirênios com endosperma uniforme imersos em água a 60 ºC por 5 minutos e posteriormente embebidos em água destilada à temperatura ambiente por 12 horas. O substrato utilizado foi uma mistura na proporção 2:1:1:1/2 (v/v) de solo, substrato comercial Bioplant®, areia de textura grossa e vermicomposto, com pirênios semeados a 1 cm de profundidade em bandejas de poliestireno expandido, mantidas em viveiro com sombrite de 50% de redução luminosa e médias de temperaturas de 19,3 ºC a mínima e 30,2 ºC a máxima e irrigadas diariamente. Das contagens diárias das plântulas emergidas foram avaliadas medidas de capacidade, tempo, velocidade, uniformidade e sincronia de emergência, além da distribuição de frequência percentual de emergência em relação ao tempo. A emergência das plântulas é tardia, irregular e assíncrona, gastando mais de 80 dias para estabilização do estande. A porcentagem de plântulas emergidas pode atingir até 57%, porém mesmo quando o endosperma ocupa toda a cavidade do pirênio e está esverdeado, a emergência das plântulas pode não ocorrer. Há variabilidade nas medidas de emergência de plântulas quando obtidas de pirênios de indivíduos distintos de Schefflera morototoni. / Mestre em Agronomia

Computing education has struggled with student engagement and diversity in the student population for a long time. Research in science, technology, engineering, and mathematics (STEM) education suggests that taking a social, long-term perspective on learning is a fruitful approach to resolving some of these persistent challenges. A longitudinal study has been conducted, following students from two computing study programmes (CS/IT) over a three-year period. The students reflected on their experiences with CS/IT in a series of interviews. Drawing on social identity theory, the analysis has focused on describing participation in CS/IT, doing, thinking, feeling in relation to CS/IT, as negotiated among different people. Phenomenographic analysis yields an outcome space that describes increasingly broad ways in which the students experience participation in CS/IT over the years. Two further outcome spaces provide nuanced insights into experiences that are of increasing relevance as the students advance in their studies; participation as problem solving and problem solving for others. Problem solving defined as solving difficult (technical) problems seems predominate in the learning environment. Problem solving for others brings the user into perspective, but first in the human computer interaction (HCI) course in year three. Students react with scepticism to HCI, excluding HCI from computing, some are students who commenced their studies with broader interests in computing. Demonstrating (technical) problem solving competence is the most vital indicator competence in the two study programmes and the students adapt their reflections on who they are as computing students and professionals accordingly. People showing broader interests in computing risk being marginalised. I identify a gap between conceptions of computing as interdisciplinary and important for society and constructions of computing as technical. Closing the gap could improve retention and diversity, and result in graduates that are better prepared to contribute to societal development.