McGill University Thèses et mémoires par auteur commençant par É

In this thesis, we consider the problem of dynamic load balancing for parallel discrete event simulation. We focus on the optimistic synchronization protocol, Time Warp. A distributed load balancing algorithm was developed, which makes use of the active process migration in Clustered Time Warp. Clustered Time Warp is a hybrid synchronization protocol; it uses an optimistic approach between the clusters and a sequential approach within the clusters. As opposed to the centralized algorithm developed by H. Avril for Clustered Time Warp, the presented load balancing algorithm is a distributed token-passing one. We present two metrics for measuring the load: processor …  Lire la suite

Schizophrenia is a disorder whose pathophysiology is thought to involve increased activity in mesolimbic dopamine (DA) systems. Epidemiological studies have indicated increased pregnancy and birth complications, especially those resulting in fetal anoxia, among those who later develop schizophrenia. Furthermore, stress plays a role in onset and relapse in psychosis. This raised the question whether early life insults, such as birth anoxia, may produce a state of hyperdopaminergia that is exacerbated by stress. This thesis used a rat model of acute global anoxia during Caesarean section (C-section) birth to test the hypothesis that early birth anoxia can produce long-term changes in …  Lire la suite

In this research, three alternative approaches to chemical preservatives to extend the mold free shelf-life and quality of pita bread were investigated namely: Modified Atmosphere Packaging (MAP) involving gas packaging, oxygen absorbents technology and ethanol vapor generators, high pressures, and direct and indirect heating. Gas packaging using 60%CO2 (balance N2) inhibited the growth of Aspergillus niger and Penicillium notatum from 3d (pita bread packaged in air) to 35d at ambient temperature. A longer extension in shelf-life (42d) was possible using an Ageless oxygen absorbent or a Freshmax oxygen absorbent label in conjunction with gas packaging. Similar results were obtained with …  Lire la suite

This Thesis presents the development and evaluation of a speech I/O interface system for a bedside data entry application in an intensive care unit. The speech I/O interface consists of a speech recognition input and a speech generation output. The main objective is to permit users to perform "hands-free" and "eyes-free" data entry. This thesis begins with a literature survey of patient data management systems, speech applications, the difficulties and the key factors of speech evaluations. This is followed by an overview of the current system. The design and the implementation of the speech interface system are described. The evaluation …  Lire la suite

English-style crumpets (pH 6--8, aw 0.97--0.99) are a popular baked product enjoyed by consumers worldwide. However, over the past few years, outbreaks of food poisoning have been caused by the growth of Bacillus cereus in crumpets. This spore forming microorganism, which originates in flour, can easily survive the baking process and grow to >106 CFU/g within 3--5 days at ambient storage temperature. Therefore, control of this pathogen is essential to ensure the safety and marketability of English-style crumpets. Initial studies were done to determine the effect of water activity ( aw), pH, modified atmosphere packaging (MAP), UV-light, bacteriocins, organic acids …  Lire la suite

Gross, Warren (Supervisor2)  Lire la suite

The Finite Element Method (FEM) is a computationally intensive scientific and engineering analysis tool that has diverse applications ranging from structural engineering to electromagnetic simulation. Field Programmable Gate Arrays (FPGAs) have been shown to have higher peak floating-point performance than general purpose CPUs, and the trends are moving in favor of FPGAs. We present an architecture and implementation of an FPGA-based Sparse Matrix-Vector Multiplier (SMVM) for use in the iterative solution of large, sparse systems of equations arising from FEM applications. Our architecture exploits the FEM matrix sparsity structure to achieve a balance between performance and hardware resource requirements. The …  Lire la suite

The current work aims at modeling a three-stage cold heading process of an industrial bolt, and presents a methodology for the optimization of preform die geometries. The process is modeled using finite element simulations and potential defects in the heading process are analyzed using external and internal crack criteria. The preform geometries are then optimized with respect to external cracking in the blank and forming die load. The conventional Taguchi approach is first applied on each criterion separately. Three optimal solutions are generated. It is found that some parameters have conflicting optimal solutions. The single criterion approach is therefore extended …  Lire la suite

"Inclusion" in the broad sense of access to, and participation in, public policy and services has been lacking in the majority of developing countries---whether authoritarian or democratic---due to highly skewed political, social and economic power structures. To understand why this tends to be the case, the dissertation provides a political economy model for understanding civil society, arguing that the evolution of civil society and its potential as a vehicle for inclusion are conditioned by the economic imperatives in place and the state prerogatives. More specifically, I question the extent to which the neoliberal model allows civil society to fulfill this …  Lire la suite

In order to reduce the test development cost and guarantee testable designs, it is essential to have synthesis transformations that are testability and test-set preserving. In this thesis, we study testability preservation of transformations that form the basis of existing state-of-the-art logic synthesis and optimization techniques. We show that the concurrent decomposition and factorization transformations, except dual-extraction of multiplexor structures, preserve testablility and test-set under several testing constraints. Furthermore, we provide sufficient conditions for test-set preservation under the algebraic resubstitution with complement transformation that cover a larger class of complementary expressions than was known previously. Experimental results show that dual-extraction …  Lire la suite

With the increasing demand for wireless voice services and limited bandwidth resources, it is critical to develop and implement coding techniques which use spectrum efficiently. One approach to increasing system capacity is to lower the bit rate of telephone speech. A typical telephone conversation contains approximately 40% speech and 60% silence or background acoustic noise. A reduction of the average coding rate can be achieved by using a Voice Activity Detection (VAD) unit to distinguish speech from silence or background noise. The VAD decision can be used to select different coding modes for speech and noise or to discontinue transmission …  Lire la suite

The purpose of this thesis is to analyze Kitab al-Tajalliyât (The Book of Theophanies), a trilogy by the contemporary Egyptian author Jamal al-Ghitani. I will be situating my analyses within the context of contemporary Arab discourse about the relationship between al-turath (tradition) and al-mu'asara (modernity). ln his experimentation with narrative strategies, al-Ghitâni constructs his works in a relationship of "hypertextuality" to conventional forms of discourse that constitute part of the Islamic turâth. In Kitab al-Tajalliyat, he parodies the genre of sufi epistles, with specifie evocation of the discourse of Muhyi al-Din Ibn 'Arabi (1165-1240). [...]  Lire la suite

Low Back Pain is currently one of the leading causes of disability worldwide. This usually initiates at the working age of young adults as acute low back pain and depending on several factors may, later, develop into chronic low back pain. While most cases of low back pain are eventually solved by nonsurgical management, those who show no sign of improvement ultimately undergo invasive surgery. Spinal Lumbar Interbody Fusion (LIF) surgeries have become well established given the progressive increase in surgical experience and knowledge. Oblique Lateral LIF (OLLIF) is one of the most recent surgical procedures which has shown advantages …  Lire la suite

"Cette dissertation est centrée autour du mot masca, qui désigne un personnage populaire et très ancien de genre féminin, qu'on retrouve exclusivement dans le folklore et la littérature de la région italienne du Piémont. On attribue à ce personnage la capacité fort rare d'exercer autant le bien que le mal, selon les circonstances. Cette dissertation fait preuve d'une recherche historique et linguistique qui puise ses données des coins les plus reculés de la civilisation celtique, au sein du territoire piémontais où elle triompha depuis le début du 4e siècle avant J.C. jusqu'au 1 er siècle de notre ère, époque à …  Lire la suite

Reading of the poetics of Beppe Fenoglio in relation to the philosophical and religious systems of the ancient Celts, a people who dominated the territory of Piedmont from the IV century BC to the I century AD. A brief explanation of the history of Piedmont from prehistoric times, through Ligurian and Celtic domination, to Roman conquest and the consequent partial romanization of the territory will introduce the subject. Certain aspects of the religion of the Celts, as described both by classical authors and modern scholars, will be examined in the context of beliefs, customs, and traditions of modern rural Piedmont …  Lire la suite

In this study, I will argue that the difference between profane love and sacred love, as examined in Jāmī's masnavī Yūsuf va Zulaykhā, can be conceptualized through vision and narrative planning. Jami's tale centers on Zulaykhā's love for Yusuf and her subsequent conversion to monotheism. The text makes extensive use of the sense of sight, especially through the trope of jelvah-i maḥbūb, the blinding hierophany of the beloved, to create meaning and to illustrate the transformation of Zulaykhā's profane love into sacred love. This transformation occurs in several stages, each of which conveys philosophical and mystical doctrines from Ibn 'Arabī.  Lire la suite

A laboratory-scale reactor with a feeding system was specially designed and built to study the continuous pyrolysis of CANMET coprocessing residue in Argon/Hydrogen plasma using an induction plasma torch. Hydrogen was injected into the argon plasma tailflame ranging in molar concentration from 0 to 23%. The residue was continuously fed to the reactor in liquid form at flow rates ranging from 6 to 9 g/min. The mean plasma temperature was varied from 2700 to 3670 K. A maximum of 10% of the residue pyrolysed with up to 90% conversion to gaseous hydrocarbons. The rate of residue pyrolysis and the rate …  Lire la suite

A new plasma fluid bed process to replace the present electric arc furnace for the production of calcium carbide has been studied. A thermodynamic analysis predicted that the solid phase reaction would be complete at 2150 K and that the plasma process could lower the energy consumption by up to 40%. A semi-batch fluid bed reactor with a DC plasma torch was used for the study. Calcium oxide powder with a mean particle size of 170 $ mu$m was reacted with two types of graphite, coke and methane. Argon was used to initiate the plasma and hydrogen gas was then …  Lire la suite

Interest in flaxseed and products derived from flaxseed has increased considerably in the past decade. In the development of nutraceutical foods, several flaxseed components including lignans and alpha-linolenic acid, have been recognized to have health benefits. There are many patents and health claims to these components; however, relatively little research and information is found on flaxseed proteins. The objective of the present study was to isolate and characterize flaxseed proteins from defatted flaxseed meal. Proteins were extracted from defatted flaxseed meal with NaOH. NaCl and NaCl/Papain. Protein solubility with these extractants ranged from 18 to 25%. Proteins were precipitated from …  Lire la suite

The purpose of the present work was to examine the effects of asphaltenes, amphiphilic molecules found in crude oils, on subsurface contamination by petroleum liquids. Initial experiments were conducted, using naphthalene as a representative target contaminant, to determine the contaminant equilibrium partitioning relationships in an asphaltene-oil-water system. Further experiments were conducted to determine if the presence of asphaltenes in petroleum liquids affected resistance to interphase mass transfer of naphthalene in situ with aging. Results were analyzed using a lumped mass transfer coefficient calculated after various aging periods. Experimental data suggested that adding increasing amounts of asphaltenes to gasoline resulted in …  Lire la suite

In this thesis we consider linear multivariable frequency response systems with finite numbers of unstable poles but with no poles on the j(omega) - axis. We represent unstable systems by input-output mappings with restricted domains in (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) The effects of unstable perturbations in an open loop system K on the closed loop system (I + K)('-1) are studied. For this purpose the gap metric is introduced for measuring approximations to unstable systems. This metric is used to determine the sets of "allowable" uncertainties, i.e., those which do not destroy the stability of a feedback …  Lire la suite

The stretch reflex response helps control upright stance by countering the effects of gravity. It has been suggested that sway in the sagittal or anterior-posterior (AP) plane contributes to the modulation of the reflex response; this thesis sought to examine if a similar relationship could be discerned between sway in the frontal or medial-lateral (ML) plane and the reflex. The sway in the ML plane was characterized by changes in the center of pressure (COP) and in the vertical forces between the feet. Two experiments were carried out. The results of the first experiment, which observed the COP and the …  Lire la suite

La schistosomiase est une maladie chronique débilitante et douloureuse qui affecte les organes viscéraux et affecte négativement la croissance et le développement des enfants. La maladie persiste dans les régions de pauvreté et dans 78 pays de régions tropicales et subtropicales ; elle est associée à une morbidité significative. La schistosomiase est une maladie de la pauvreté qui se rencontre dans les régions qui n'ont pas accès à l'eau potable propre. Les agents pathogènes de la schistosomiase sont les trématodes de l'espèce Schistosoma. La migration des larves et la persistance de l'infection chez l'hôte sont réglementés par l'interaction des neurotransmetteurs …  Lire la suite

La tension entre la fourniture de services aux groupes marginalisés et l'organisation desrevendications afin de défier les structures de pouvoir est un dilemme fondamental pour lesOrganisations de Services de Changement Social. Ce dilemme existe dans de nombreusesorganisations de sociétés civiles, en particulier parmi les organisations qui travaillent avec descommunautés marginalisées et subjuguées telles que la minorité indigène Bédouine qui demeureen Israël, où la prestation de services immédiats et la promotion de changements politiques sonttout aussi prépondérantes. Il existe une littérature riche concernant les tensions qui proviennentdu groupement des services de disposition et revendication, car ces approches nécessitentchacune leur propre structure …  Lire la suite

The genome of the human bloodfluke Schistosoma mansoni encodes 18 putative biogenic amine-like G-protein-coupled receptors (GPCRs). These receptors are potential targets for the development of antischistosomal drugs. One of these sequences, SmGPR-1 (formerly SmGPCR), was previously cloned and was identified as a histamine receptor. In this study, we expanded the functional analysis of SmGPR-1 by studying its expression and tissue distribution both at the RNA and protein levels in different developmental stages of the parasite. In the second part of the study, we cloned and characterized two structurally related receptors, named SmGPR-2 and SmGPR-3. Bioinformatics analyses showed that the three …  Lire la suite

This dissertation examines the thought of Palestinian-American literary scholar Edward W. Said and selected works by London-born Egyptian artist Hassan Khan. Through a comparison and contrast of their respective approaches to the production and critique of Arab representations I argue that Said's work from the 1970s and 1980s is of lasting importance for art historians dealing with contemporary art from the Middle East in general and Khan's work in particular. Much recent scholarship on contemporary art in the Middle East and Egypt has focused on features of artworks that contribute to notions of Arab political, ethnic and national identity. While …  Lire la suite

The problem of enriching distributed communication has been tackled extensively by conventional investigations of videoconferencing technology. However, standard tools for computer-mediated communication have yet to oer a level of social engagement that compares to the gold standard of face-to-face interaction. While a number of systems attempt to bridge this gap by providing reasonable support for non-verbal cues, such systems typically attempt to improve collaboration of a practical nature. As such, we were interested in exploring the extent to which computer-mediatedtechnology could support human activities necessitating a greater level of creativity, playfulness and spontaneity. An additional motivation was understanding how distributed …  Lire la suite

This thesis seeks to sketch the outer contours of the epistemological universe in which the science of us&dotbelow;ul al-fiqh was elaborated in classical Islam. The task is accomplished by analyzing arguments both for and against qiyas and ta`lil as presented by two major jurists of the 5th century of the Hijra representing opposite ends of the Islamic theological spectrum: (1) the H&dotbelow;anafite Mu`tazilite jurist Abu l-H&dotbelow;usayn al-Bas&dotbelow;ri (d. 436/1044) and (2) the Z&dotbelow;ahirite Abu Muh&dotbelow;ammad `Ali ibn H&dotbelow;azm al-Andalusi (d. 456/1064). After detailing each author's stance regarding the justifiability of qiyas and ta`lil, the thesis analyzes the underlying theological and …  Lire la suite

Hallaq, Wael (Supervisor1)  Lire la suite

One of the major quality problems encountered in continuous casting is the formation of transverse cracks, which is partly due to the poor hot ductility of the cast steel. In this work, high temperature tensile testing is used to determine the hot ductility of a Nb-Ti and Ti-B microllayed steels. The influence of reheat treatment on hot ductility of the alloys is studied. In order to accomplish this task, steel specimens were reheated near the incipient melting temperature, and subsequently tensile tested to fracture at a strain rate typical of the unbending operation over a range of temperatures, in order …  Lire la suite

Five steels were used in the present work to investigate the dynamic, static and metadynamic recrystallization behavior of hypereutectoid steels of 1% carbon, alloyed with high silicon and microalloying levels of vanadium. Compression tests were performed using single and double hit schedules at temperatures between 875--1100ºC, strain rates of 0.01s-1 -1s-1, and inter-pass times of 0.1--500 seconds and 0.1--30 seconds for static recrystallization and metadynamic recrystallization, respectively. For dynamic recrystallization, it was found that an increase in carbon and vanadium content led to smaller grain sizes. Equations were generated that can be used to predict the critical strain for dynamic …  Lire la suite

"An experiment was conducted to evaluate the performance of winter cereals in mixtures compared to monocultures. Mixed cropping is an old concept applied to maximize productivity. Seven cultivars were grown in a diallel mixture design resulting in 28 binary combinations. OAC-HALTON barley has 3 undesirable characteristics resulting in reduced grain yield. It suffers from winter killing. Shatters readily and has asynchronous tiller maturity. YORKSTAR wheat performed better than SUNDANCE both in mixtures and pure stands. There were no significant differences in grain yields of 3 rye cultivars. OAC WINTRI showed good performance. It is difficult to draw conclusions based on …  Lire la suite

This dissertation is a result of an epidemiological prospective cohort study carried out among apprentice welders at four vocational teaching institutions in welding profession in the Montreal region, for the purpose of: (1) assessing the respiratory health of students, before starting welding, such as respiratory symptoms suggestive of asthma, lung function and bronchial responsiveness as well as immunological sensitization to common allergens and to metals; (2) providing a reassessment of the respiratory health of these same students as well as an assessment of the incidence of systemic symptoms suggestive of metal fume fever (MFF) after being exposed to welding fumes; …  Lire la suite

The bilateral air transport agreement that was signed thirty years ago between the United Kingdom and the United States received almost universal acceptance. That agreement ls known as the "Bermuda Agreement". Its principles were followed by the majority of states. This thirty-year-old Agreement was denounced by the United Kingdom on June 1976.  Lire la suite

La mobilité urbaine en Amérique Latine se base fondamentalement sur la marche à pieds et les deux roues motorisés DRM. Mise à part l’importance des deux derniers, la sécurité routière de ces moyens de transport représente une vulnérabilité assez remarquable par leurs utilisateurs. Cela s’impose en tant que problématique majeure dans les pays concernés. Le taux d’accident que provoque la marche à pieds ou les DRM représente à peu près la moitié du taux d’accidents sur le continent Latino-Américain selon des statistiques établit en 2015 par l’organisation mondiale de la santé qui déclare que 22% des accidents routières émanent des …  Lire la suite

Cette thèse se concentre sur la réaction du citoyen international, vaguement inquiet, aux rapports sur les conflits ethniques lointains. Plus précisément, ces conflits sont des situations complexes, déterminées par l'histoire et sanctionnées par l’État, dans lesquelles une communauté ethnique est prise pour cible par les Autres. La personne nominalement concernée dans un pays lointain qui observe les Autres pris dans un conflit est définie comme un spectateur en raison de la nature théâtrale de l’acte. Le spectateur s'engage dans un spectacle multimédia par le biais des journaux, de la télévision et de l'internet, avec des reportages qui se présentent sous …  Lire la suite

Previous research has demonstrated regional variations in the thickness of the calvarium which can adversely affect surgery in this region. An accurate intraoperative method of skull thickness measurement is not available to enhance the safety and efficacy of these procedures. The aim of this research represents the first attempt to examine the reliability of A-mode ultrasound for this purpose. Acoustic measures of bone thickness were analyzed followed by serial modifications of existing ultrasound probes. Standardized calvarial sites were identified and marked for experimentation with human cadaveric and live animal skull models. The individual points were insonified using an appropriately calibrated …  Lire la suite

ContexteAu milieu d'un enthousiasme considérable entourant l'intégration de l'intelligence artificielle (IA) dans divers secteurs, les rôles significatifs de l'IA dans les écosystèmes de soins de santé multifacettes restent flous. Les premiers efforts étaient axés sur des systèmes simples basés sur des règles et des outils de stockage de données. Les progrès dans le domaine ont conduit au développement d'outils avancés d'imagerie médicale et de systèmes de soutien à la décision axés sur le raisonnement basé sur des règles. Malgré leurs limitations, ces précurseurs ont préparé le terrain pour des avancées ultérieures dans les algorithmes d'apprentissage automatique, qui ont trouvé des …  Lire la suite

The issue of mold cooling is one, which presents a foundry with a dilemma. On the one hand; the use of air for cooling is safe and practical, however, it is not very effective and high cost. On the other hand, water-cooling can be very effective but it raises serious concerns about safety, especially with a metal such as magnesium. An alternative option that is being developed at McGill University uses heat pipe technology to carry out the cooling. The experimental program consisted of designing a permanent mold to produce AZ91E magnesium alloy and A356 aluminum alloy castings with shrinkage …  Lire la suite

Nicolau, Belinda Farias (Supervisor1)  Lire la suite

Allison, Paul J. (Supervisor1)  Lire la suite

Objectives: To identify correlates of psychological distress and to investigate how coping skills, anxiety and depression are related in a group of head and neck cancer patients 6-12 months after their diagnosis. Methods: We evaluated in 107 head and neck cancer patients their anxiety and depression levels using the Hospital Anxiety and Depression Scale, and their Coping strategies using the Ways of Coping Checklist. Results: There were statistically significant associations between gender and anxiety level, and between living arrangements, cancer site, time since treatment, tumor stage and depressive symptoms. Results also showed that patients used a variety of coping strategies. …  Lire la suite

Résumé:Les programmes de dépistage du cancer du poumon offrent une opportunité importante pour améliorer le diagnostic et le traitement de la maladie pulmonaire obstructive chronique (MPOC) chez les personnes à haut risque. La MPOC est l'une des trois principales causes de mortalité dans le monde, et demeure largement sous-diagnostiquée, notamment en raison de la présentation clinique hétérogène de la maladie. La majorité des patients reçoivent un diagnostic à un stade modéré ou sévère, lorsque les symptômes sont plus marqués et que la qualité de vie est déjà compromise. Les personnes admissibles au dépistage du cancer du poumon sont particulièrement à …  Lire la suite