VictorJuiz/thesis huggingface dataset:
Affinity Propagation: Clustering Data by Passing Messages

Clustering data by identifying a subset of representative examples is important for detecting patterns in data and in processing sensory signals. Such "exemplars" can be found by randomly choosing an initial subset of data points as exemplars and then iteratively refining it, but this works well only if that initial choice is close to a good solution. This thesis describes a method called "affinity propagation" that simultaneously considers all data points as potential exemplars, exchanging real-valued messages between data points until a high-quality set of exemplars and corresponding clusters gradually emerges. Affinity propagation takes as input a set of pairwise similarities between data points and finds clusters on the basis of maximizing the total similarity between data points and their exemplars. Similarity can be simply defined as negative squared Euclidean distance for compatibility with other algorithms, or it can incorporate richer domain-specific models (e.g., translation-invariant distances for comparing images). Affinity propagation’s computational and memory requirements scale linearly with the number of similarities input; for non-sparse problems where all possible similarities are computed, these requirements scale quadratically with the number of data points. Affinity propagation is demonstrated on several applications from areas such as computer vision and bioinformatics, and it typically finds better clustering solutions than other methods in less time.

Keywords: Computer Science
Machine Learning
Exemplar-based clustering
Factor Graph
Belief Propagation
Advisor: Frey, Brendan J.
Modelling and Performance Evaluation of the Virtual Air Gap Variable Reactor

This thesis describes a novel device, the Virtual Air Gap Variable Reactor (VAG-VR), which is capable of producing a continuously variable reactance by locally saturating a small section of the reactor core via an embedded dc control winding. Variable Reactors have many applications in the power industry such as control of line power flow, voltage regulation, reactive line compensation and limiting inrush currents. A variable reactor is most commonly implemented as a thyristor controlled reactor (TCR) by switching in and out a constant reactance to achieve an averaged variable reactance. By using a virtual air gap, a continuously variable reactance is possible. The VAG-VR offers a better dynamic response, without introducing the harmonics created by the thyristor switching of a TCR. The VAG-VR gives low triplen harmonics and therefore allows control of reactive power in single phase or unbalanced three phase systems as would be required in the distribution system. An experimental prototype VAG-VR was developed to investigate three main performance measures: steady state performance, dynamic response and harmonic performance. Over the operating range of the VAG-VR inductance was varied from 100% to 9% of its original value. The dynamic response of the VAG-VR is approximately one tenth of a cycle. This compares favorably to a TCR which responds in approximately half a cycle. Harmonics are also shown to be significantly reduced in the VAG-VR compared to the TCR. A dynamic model of the VAG-VR, suitable for incorporation into power system simulations, was developed and validated. Parameters were determined both experimentally and through finite element method (FEM) simulations. Both experimental and simulation results indicate that the VAG-VR offers a technically viable alternative to the TCR.

Keywords: Virtual Air Gap
Variable Reactor
VAG-VR
Advisor: Lehn, Peter W.
Splashing and Breakup of Droplets Impacting on a Solid Surface

Two new mechanisms of droplet splashing and breakup during impact have been identified and analyzed. One is the internal rupture of spreading droplet film through formation of holes, and the other is the splashing of droplet due to its freezing during spreading. The mechanism of film rupture was investigated by two different methods. In the first method, circular water films were produced by directing a 1 mm diameter water jet onto a flat, horizontal plate for 10 ms. In the second method, films were produced by making 0.6 mm water droplets impact a solid surface mounted on the rim of a rotating flywheel. Substrate wettability was varied over a wide range, including superhydrophobic. In both cases, the tendency to film rupture first increased and then decreased with contact angle. A thermodynamic stability analysis predicted this behavior by showing that films would be stable at very small or very large contact angle, but unstable in between. Film rupture was also found to be promoted by increasing surface roughness or decreasing film thickness. To study the effect of solidification, the impact of molten tin droplets (0.6 mm diameter) on solid surfaces was observed for a range of impact velocities (10 to 30 m/s), substrate temperatures (25 to 200°C) and substrate materials (stainless steel, aluminum and glass) using the rotating flywheel apparatus. Droplets splashed extensively on a cold surface but on a hot surface there was no splashing. Splashing could be completely suppressed by either increasing the substrate temperature or reducing its thermal diffusivity. An analytical model was developed to predict this splashing behavior. The above two theories of freezing-induced splashing and film rupture were combined to predict the morphology of splats typically observed in a thermal spray process. A dimensionless solidification parameter, which takes into account factors such as the droplet diameter and velocity, substrate temperature, splat and substrate thermophysical properties, and thermal contact resistance between the two, was developed. Predictions from the model were compared with a wide range of experimental data and found to agree well.

Keywords: Fluid Dynamics
Heat Transfer
Droplet Impact
Droplet Splashing
Thermal Spray Coating
Water Jet Impact
Advisor: Chandra, Sanjeev
"Les Romans Mis en pièces": étude sur la Pratique de l'Adaptation Théâtrale à la fin du XIXe Siècle. Le Cas d'Émile Zola (1873-1902)

Résumé Le XIXe siècle marque la consécration d’une nouvelle tendance au théâtre : la représentation de pièces tirées de romans. En France, cette pratique connaît, surtout dans la seconde moitié du siècle, une popularité sans précédent. La thèse est une étude historique de ce phénomène. La première partie situe la pratique de l’adaptation dans le contexte culturel de la deuxième moitié du XIXe siècle. La deuxième partie étudie les conditions qui entourent la production de ce type de pièce (lieux de représentation, auteurs, éditeurs). Nous nous intéressons aussi dans cette partie au discours critique et à la perception des adaptations théâtrales dans le milieu littéraire. Enfin, la troisième partie se concentre sur les adaptations théâtrales tirées des œuvres d’Émile Zola et représentées à Paris entre 1873 et 1902. Zola fut l’un des auteurs les plus adaptés sur scène au cours de cette période. En cherchant à situer l’œuvre et la participation du chef de file de l’école naturaliste dans ce phénomène théâtral, nous étudions d’abord les positions de Zola à l’égard de la pratique de l’adaptation telles qu’elles s’expriment à travers les chroniques dramatiques et les entrevues qu’il publia dans les journaux. Le deuxième chapitre de cette partie examine la production des adaptations de ses romans et de ses nouvelles représentés à la scène. Notre analyse porte, en dernier lieu, sur la réception de ces œuvres dans la presse à la fin du XIXe siècle. Enfin, nous soulignons dans la conclusion que la pratique de l’adaptation au théâtre participe au développement d’une « culture de l’image » dont le cinéma s’avère le successeur au XXe siècle.

Keywords: théâtre
Zola
adaptation
Advisor: Speirs, Dorothy
Portebois, Yannick
Uncomfortable Mirrors: Religion and Mimetic Violence in Contemporary Canadian Native Literature

This study considers religion and mimetic violence in the work of four contemporary Canadian Native writers: Maria Campbell, Beatrice Culleton, Thomas King, and Basil Johnston. The mimetic violence examined is both social (the colonial attempt to remake the colonized into a reflection of the dominant culture) and personal (inter-Native conflict in which participants mirror one another in their struggle for a mutually covetted object). In order to investigate the former, I rely on the work of Homi K. Bhabha on colonial mimicry and hybridity; to examine the latter, I employ René Girard’s model of mimetic desire and violence. The principal academic contexts to this work are the study of Native literature and the academic study of religion, including the sub-field of Religion and Literature. After reviewing the relevant literature in these fields, and examining mimetic violence in key texts by the Native authors listed, I make several concluding points. First, I argue that a causal link between colonial violence and inter-Native mimetic violence is evident in the category of Native literature labelled by Thomas King as “polemical.” This includes Campbell’s Halfbreed, Culleton’s In Search of April Raintree, and King’s own Green Grass, Running Water. Second, I find that Johnston’s Moose Meat & Wild Rice and Indian School Days generally take care to separate colonial mimesis from Native mimetic conflict. This work fits King’s “associational” category of Native literature, and the disconnect evident in Johnston’s stories between the two forms of mimesis might stand as a defining feature of this category. Third, I assert that in none of the Native literature examined is religion viewed in a positive, idealist manner that assumes in its “true” manifestation it cannot be the cause of violence, which is the position taken by most religion scholars. I argue that the emphasis the Native texts place on the historic, material actions and effects of Christian individuals and institutions complements similar work being done by a minority of academics in the study of religion. Fourth, I propose possible avenues for the further investigation of mimesis in Native literature, which would use/focus on: metaphor-centred hermeneutical models; trickster figures and theories; and the conception of both Native and colonial identity. Finally, I argue that critics of Native literature have tended to idealize Native cultures, and that inter-Native mimetic violence offers a humanizing corrective to this perspective.

Keywords: Canadian Literature
Native American Studies
Native Literature
Violence
Religion and Literature
Colonialism
Advisor: Kanaganayakam, Chelva
Behaviour of Normal and High Strength Concrete Confined with Fibre Reinforced Polymers (FRP)

An extensive amount of research has been reported in previous literature on the behaviour of FRP-confined concrete subjected to concentric axial compression. However, data on the behaviour of high strength concrete confined with various types and configurations of FRP systems is still lacking and no consensus exists on the complete response of FRP-confined concrete. In addition, no appropriate design guidelines are currently available. This thesis reports results from an experimental program involving 112 cylindrical concrete specimens, 88 of which were FRP-wrapped and the remaining 24 were control specimens. All the specimens were 152 mm in diameter and 305 mm in length. Test variables included: amount of FRP materials used, strength and stiffness of FRP materials, concrete strength, and the health of concrete at the time of strengthening. Experimental results indicated that a pre-repair load of up to 77% of the unconfined concrete strength had no appreciable effect on the stress-strain response of FRP-confined concrete. With an increase of the unconfined concrete strength, the strength enhancement, energy absorption capacity, ductility factor and work (energy) index at rupture of FRP jackets all decreased remarkably. A positive correlation was found between confined concrete ductility and FRP rupture strain. In addition, a gradual post-peak failure of the specimens, observed previously from FRP-confined concrete columns tested at the University of Toronto, was also observed in some of the current tests -- owing to the high speed data acquisition system. That ductile failure can be attributed to the gradual unzipping failure of FRP jacket, which in turn is related to specimen size. A new constitutive model was developed based on material properties, force equilibrium and strain compatibility. The size effect was taken into account in the model, which is able to accommodate concrete with a wide range of strength (25 MPa to 110 MPa) confined with various types and configurations FRP systems. Design equations from CSA S806-02 and CSA S6-06 provide reasonable and conservative estimates for the FRP-confined concrete strength. To calculate the peak strain for FRP-confined concrete, an equation based on the work by Berthet et al. (2006) is proposed.

Keywords: Concrete
Confinement
Stress-strain model
Fibre reinforced polymer
Advisor: Sheikh, Shamim A.
A Grounded Theory of Intensive Care Nurses’ Experiences and Responses to Uncertainty

The purpose of this study was to develop a theory to explain how nurses experience and respond to uncertainty arising from patient care-related situations and the influence of uncertainty on their information behaviour. Strauss and Corbin’s (1998) grounded theory approach guided the study. Semi-structured face-to-face interviews were conducted with 14 staff nurses working in an adult medical-surgical intensive care unit (MSICU) at one of two participating hospitals. The grounded theory recognizing and responding to uncertainty was developed from constant comparison analysis of transcribed interview data. The theory explicates recognizing, managing, and learning from uncertainty in patient care-related situations. Recognizing uncertainty involved a complex recursive process of assessing, reflecting, questioning and/or predicting, occurring concomitantly with facing uncertain aspects of patient care situations. Together, antecedent conditions and the process of recognizing uncertainty shaped the experience of uncertainty. Two main responses to uncertainty were physiological/affective responses and strategies used to manage uncertainty. Resolved uncertainty, unresolved uncertainty, and learning from uncertainty experiences were three consequences of managing uncertainty. The ten main categories of antecedent, actions and interactions, and consequences that comprised the theory were interrelated and connected through temporal and causal statements of relationship. Nurse, patient, and contextual factors were linked through patterns of conditions and intervening relational statements. Together, these conceptual relationships formed an explanatory theory of how MSICU nurses experienced and responded to uncertainty in their practice. This theory provides understanding of how nurses think through, act and interact in patient situations for which they are uncertain, and provides insight into the nature of the processes involved in recognizing and responding to uncertainty. Study implications for practice, nursing education, and further theory development and research are discussed.

Keywords: nurse, uncertainty, grounded theory, interviews, intensive care unit, decision making, information seeking
Advisor: Doran, Diane
Rhetoric of Modern Jewish Ethics

Jewish ethicists face a twofold task of persuading audiences that (a) their proposal for an issue of social concern and justice is the right and good thing to do, and (b) their proposal fits within the Judaic tradition writ large. Whereas most scholarship in the field focuses on how Jewish ethicists argue by dividing arguments into halakhic formalist, covenantalist and narrativist categories, these efforts fail both to reflect the diverse ways ethicists actually argue and to explain why they argue in these ways. My project proposes a new methodology to understand how and why Jewish ethicists argue as they do on issues of justice and concern. My project combines philosophical theology and discourse analysis. The first examines an ethicist’s notion of covenant (brit) in light of theories found in the Jewish textual tradition. Clarifying an ethicist’s notion of covenant uncovers that person’s assumptions about the scope and binding nature of elements in the Judaic tradition, and that person’s conception of an audience’s responsibilities to the normative argument s/he articulates. Certain themes come to the fore for each ethicist that, when mapped, reveal striking relationships between an ethicist’s notion of covenant and anticipated ethical rhetoric. These maps begin to show why certain ethicists argue as they do. Discourse analysis then identifies the interrelationships between the speaker, the spoken and the audience – as they are actually articulated in Jewish ethicists’ practical arguments. These relationships form the how of Jewish ethical arguments insofar as they reflect an author’s rhetorical choices. My project applies discourse analysis to the rhetoric of a sample of living Jewish ethicists (J. David Bleich, Elliot Dorff, Eugene Borowitz) who speak out on issues of social concern and justice. As will be seen, a rich and complex relationship exists between an ethicist’s theory of covenant and his subsequent moral rhetoric. This twofold methodology enables the student of Jewish ethics to understand how and why seemingly disparate styles of normative speech are nonetheless participating in a common endeavor and discourse. And it supports the theologically-based rhetoric of religious ethical discourse in shaping justice in multi-cultural societies.

Keywords: Religion
Philosophy of Religion
Ethics
Rhetoric
Jewish Ethics
Religious Ethics
Discourse Analysis
Advisor: Novak, David
Gibbs, Robert B.
Sulphur Amino Acid Requirement and Metabolism in the Total Parenteral Nutrition (TPN) Fed Human Neonate

Except for tyrosine, the amino acid requirement of parenterally fed (PN) human neonates has not been derived. Methionine and cysteine are indispensable and dispensable sulphur amino acids respectively. Cysteine is synthesized from methionine. Cysteine is unstable in solution, and is left out or added in very small amounts to amino acid solutions. Methionine is added to compensate for the lack of cysteine, assuming that the neonate will convert methionine to cysteine to meet the body’s metabolic demand. Methionine is hepatotoxic and there is evidence that the neonate has limited ability for its conversion to cysteine. To determine the requirement of the neonate for methionine, PN-fed, stable, post-surgical neonates received graded intakes of methionine. The mean methionine requirement was estimated to be 49 mg.kg-1.day-1, which is 48 to 90% of the methionine content of current commercial amino acid solutions. Because cysteine is the rate limiting substrate for glutathione (GSH) synthesis and current methods of determining amino acid requirement measure requirement for protein synthesis, SAA requirements for maintenance of GSH status was deleniated in healthy adult males and in PN-fed human neonates. GSH kinetics was measured in healthy men receiving the mean methionine requirement and graded intakes of cysteine. GSH synthesis did not change with the addition of cysteine. Additionally, PN-fed post-surgical neonates recieved a methionine-adequate cysteine-free PN followed by cysteine supplemented PN for two 3-day periods and GSH kinetics measured on days 3 and 6. There was no change in GSH synthesis in response to cysteine supplementation. It is concluded that the PN-fed human neonate is capable of synthesizing enough cysteine from methionine not only for protein synthesis but for GSH synthesis. For both healthy men and stable post-surgical neonates, the requirement for GSH synthesis is met at the sulphur amino acid requirement derived using the indicator amino acid technique

Keywords: sulphur amino acids
methionine
cysteine
glutathione
neonate
methionine requirement
parenteral nutrition
antioxidant
amino acid requirement
methionine requirement
parenteral nutrition associated cholestasis
cysteine metabolism
methionine metabolism
cystathionine
homocysteine
urinary sulphate
breakpoint analysis
Advisor: Pencharz, Paul B.
In Vivo Analysis of Cruciform Extrusion and Resolution of DNA Palindromes in Eukaryotes

DNA palindromes are implicated in several examples of gross chromosomal aberrations in the human genome, however, the molecular mechanism(s) that govern palindrome instability are largely under-investigated. Because of their propensity for intrastrand base pairing, it is suspected that the acquisition of a secondary structure, such as a hairpin or cruciform, instigates the rearrangement process. A significant hurdle in defining palindrome-provoked instability lies in the fact that reliable methods for examining in vivo cruciform extrusion remain underdeveloped. A challenge is to provide straightforward evidence for cruciform extrusion in eukaryotic cells. Here, I present a plasmid system for use in Saccharomyces cerevisiae that enables for the detection of cruciforms in vivo. Cruciform extrusion, of either an in vitro-prepared palindrome or a near-palindrome from the human genome, is monitored by scoring for the product of cruciform resolution, being a dually hairpin-capped linear DNA molecule. These results not only provide evidence for the occurrence of cruciform extrusion in eukaryotic chromatin, they also identify a novel source of endogenous double strand break formation. A screen for candidate genes that are required for resolution revealed that the Mus81 Endonuclease, a candidate Holliday junction resolvase, provides the majority of cruciform resolution activity in mitotic cells, validating the notion that cellular HJ resolvases can misrecognize a cruciform for a Holliday junction. A second screen identified a requirement for the Sgs1-Top3-Rmi1 complex in the prevention of double strand break formation, including cruciform resolution, of DNA palindromes. These results uncover a new role for the RecQ helicase in prevention of palindrome-provoked instability, possibly through the intrusion of cruciform structures. Together, this work contributes significantly to our understanding of cruciform metabolism in eukaryotes and supports suggestions that cruciform extrusion instigates instability in the human genome.

Advisor: Lewis, Susanna