title: Atomistic simulations of irradiation-induced dislocation loops in zirconium alloys

contributor:
Daymond, Mark
Yao, Zhongwen
Mechanical and Materials Engineering

subject:
Irradiation defects
Molecular dynamics simulations
Dislocation loops
Nuclear structural materials

abstract:
Irradiation-induced dislocation loops are important defects that affect zirconium alloys used in the manufacture of major structural components of nuclear reactors. In this thesis atomistic simulations and theoretical modellings are performed to analyze and explain experimental observations made by other authors. The formation and growth of different types of dislocation loops are believed to be responsible for different stages of irradiation damage, and it is necessary to understand their formation and development. However, the fundamental mechanisms behind them are still not fully elucidated. Therefore, the aim of this thesis is to investigate formation and growth mechanisms of different types of dislocation loops under various complex irradiation environments.
The background and importance of dislocation loops are introduced in Chapter 1, and a literature review is given in Chapter 2. In Chapter 3, we use both a model of dislocation energy and MD simulations to explore the habit planes of 𝑎-type dislocation loops, while cascade simulations are produced to investigate the effect of irradiation on those loops. In Chapter 4, cascade simulations with different PKA energies were performed to interact with pre-existing 𝑎-type loops; 𝑐-component interstitial loops were only observed under the condition of high-energy PKAs. The role of Ni segregation on the stability of dislocation loops in the Zr-Ni binary system is elucidated by employing molecular dynamics/Monte Carlo simulations in Chapter 5. In Chapter 6, the formation mechanisms of 𝑎-type and 𝑐-component dislocation loops in α-Zr were investigated by a combination of a fully constrained analytical model and molecular dynamics simulations. In Chapter 7, the effect of existing microstructural elements on primary damage production in α-Zr —and vice-versa—is assessed by molecular dynamics simulations. For better replicating in-reactor alloys, the influence of iron segregation to the dislocation loops is assessed. The main conclusions of this thesis are described in Chapter 8, and some interesting future work is also discussed.

abstract: PhD


title: Organic and Metallo-Organic Platforms for Nucleic Acid Recognition: Synthesis, Self-Assembly, and Biophysical Studies

contributor:
Petitjean, Anne
Chemistry

rights: Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada

rights: ProQuest PhD and Master's Theses International Dissemination Agreement

rights: Intellectual Property Guidelines at Queen's University

rights: This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.

subject: Supramolecular chemistry, nucleic acid recognition, guanine quadruplexes

abstract:
In biological systems, the self-assembly of intricate three-dimensional nucleic acid architectures, from double-stranded DNA duplexes to four-stranded DNA and RNA guanine quadruplexes, is driven by non-covalent interactions. The selective recognition of guanine quadruplexes by artificial binders through such interactions is a rapidly expanding field of research, inspired by the growing awareness of the regulatory roles these structures play in essential biological processes associated with the development of diseases such as cancer. This thesis describes three classes of organic and metallo-organic guanine quadruplex binders, many of which are obtained from organic chelates that either undergo dynamic self-assembly in the presence of labile or semi-labile metal ions or form inert coordination complexes. An alternate synthesis of a known binder is also reported.

In Chapters 2 and 3, the synthesis of four novel ligands comprised of two 2-(1,2,3-triazol-4-yl)pyridine “Click” chelates connected to an aromatic unit by hinges of controlled length and flexibility has been reported. An exploration of the self-assembly of acridine-based ligands with semi-rigid or flexible hinges into dinuclear metallo-cylinders or mononuclear metallo-macrocycles in the presence of zinc(II), iron(II), copper(II), and copper(I) in Chapter 2 will inform the rational design of future ligands for predictable self-assembly into either architecture. In Chapter 3, the coordination geometries of zinc(II), copper(II), and palladium(II) have been used to tune metallo-macrocycle topologies, thereby creating a library of possible guanine quadruplex binders from a single ligand.

In Chapter 4, an alternate synthesis of “gold standard” guanine quadruplex binder Phen-DC3 is described. This route minimizes the use of hazardous reagents and doubles the overall synthetic yield, promoting its use as a standard in biophysical assays.

In Chapters 5 to 7, a novel platinum(II) platform has been identified as the first example of a planar metal complex capable of selectively recognizing quadruplexes with high affinity on a level comparable to Phen-DC3. The synthesis and biophysical studies of second-generation binders demonstrate that this platform can be readily derivatized with various chemical functionalities to enhance quadruplex binding affinity and selectivity. In the future, this may enable the specific targeting of particular quadruplexes and allow binder properties to be tuned for therapeutic applications.

abstract: PhD


title: Exhibiting Diplomacy: Art and International Cultural Relations in Canada

contributor:
Brison, Jeffrey
Jessup, Lynda
Cultural Studies

subject: Cultural Diplomacy

subject: Canadian Art

subject: Canadian Cultural History

subject: Venice Biennale

subject: São Paulo Bienal

subject: Canadian Cultural Centre, Paris

subject: Canada House, London

subject: Cultural Relations

abstract:
In this dissertation, I analyze Canadian cultural diplomacy through the international exhibition of art, with particular consideration for the various ways in which state institutions have utilized art as an expedient in this context. Through a historical analysis that considers the significance of liberal ideologies to hegemonic formations of the Canadian nation and culture, I examine what Canadian government institutions hoped to accomplish through the international exhibition of art, and why art exhibitions in particular were utilized as an expedient in this context. In the following chapters, I map out several distinct yet interrelated examples of cultural diplomacy, all of which involve key metropoles in the Western art world as well as significant allies within Canadian foreign policy. I discuss the earliest instances of Canadian participation in the Venice and São Paulo Biennials in the 1950s; the Canadian Cultural Centre in Paris and Canada House in London during the 1970s, which were government-run cultural centres closely associated with an attendant embassy; and 49th Parallel: Centre for Contemporary Canadian Art, a government-run commercial art gallery which operated in New York from 1981 to1992.
I argue that the Canadian federal government mobilized visual art as a means of cultural diplomacy in a bid to project an image of Canada as culturally, and by extension, politically significant, in order to broker relations with a network of liberal-minded nation-states, and to project internationally a cultural image distinct from that of the U.S. Further, I argue that the Department of External Affairs was attempting to not only project Canadian culture abroad, but to actually create the nation’s status as a culturally significant middle power. To this end, the examples I discuss in this dissertation demonstrate that projects of Canadian cultural diplomacy involve complex dialogues with powerful cultural and political agents. These dialogues, thus, reveal some of the strategic intricacies of negotiating cultural, political, and economic interests related to Canada’s asymmetrical power relations with the U.S. and other states.

abstract: PhD


title: Population decline in an avian aerial insectivore (Tachycineta bicolor) linked to climate change

contributor:
Bonier, Frances
Biology

rights: Attribution-NonCommercial-NoDerivs 3.0 United States

subject:
tree swallow
climate change
insect availability
population decline
long term monitoring
avian aerial insectivore

abstract: Avian aerial insectivores, a taxonomically diverse guild of birds, are facing dire population declines. The primary commonality among these birds is that they forage on flying insects, suggesting that diet has exposed these birds to environmental challenges that cause their decline, but it has been unclear how. For most aerial insectivores the demographic data necessary to isolate the cause of decline are lacking. However, using data from a tree swallow (Tachycineta bicolor) population that has been continuously monitored from 1975-2017, I investigated demographic and environmental causes of population decline. In my first chapter, I conducted a life stage simulation to determine which demographic transitions had the most influence on population growth rates, finding that juvenile and adult survival overwinter fledging success had the potential to influence population growth. In my second chapter, I found that both juvenile survival and fledging success declined concurrently with the overall population decline. Poor fledging success was associated with increased predation and rainy, cold weather during nestling development. When raining or cold, the flying insects nestlings rely on are inactive, likely causing temporary food shortages. Low juvenile survival overwinter was linked to poor weather conditions during the post-fledging period and perhaps to conditions on the wintering grounds. Finally, in my third chapter I show that the body mass of older nestlings that are approaching fledging has declined over time. In 2017, nestlings were lighter for their age after rainy weather, suggesting that increasingly poor growth could be explained by more spring rain. As a consequence of climate change, rainfall during nestling development had increased 9.3±0.3 mm/decade, explaining poor nestling growth, fledging success, and potentially juvenile survival. Overall, my findings show that declining nestling and juvenile survival may be driven by increasingly rainy weather, which may in turn cause decline in this tree swallow population and avian aerial insectivores more generally. Therefore, I suggest that tree swallows and other avian aerial insectivores be added to the growing list of species threatened by climate change.

abstract: M.Sc.


title: Novel Sensors for Improving Reinforced Concrete Design and Assessment

contributor:
Hoult, Neil
Civil Engineering

subject:
reinforced concrete
fibre optic sensors
cracking
strain
deflection
structural health monitoring
building design
assessment
structural modelling

abstract:
The rate that reinforced concrete (RC) infrastructure is being constructed around the world continues to increase, placing significant stress on the environment. Thus, it is important that any inefficiencies in RC design and assessment be minimized by structural engineers moving forward. For progress to be made on this front, RC behaviour must be measured in a more comprehensive way to further understand its complex behaviour and explore avenues for refinement. This thesis investigates the use of novel sensors for this purpose, with a particular focus on distributed fibre optic sensors (FOS).
	An experimental campaign containing 18 RC beam specimens was performed to assess the advantages of using FOS to measure RC behaviour. Practical methods were developed for measuring distributed deflections, crack widths, and distributed reinforcement strains. The results showed that full deflected shapes could be captured up until failure and all crack widths lower than 0.3 mm could be measured. Additionally, reinforcement strain profiles were accurately measured for steel reinforcement embedded in RC elements using FOS, amounting to hundreds of strain measurements spaced by 10 mm along each bar’s entire length.
	A load test on an RC building in Ottawa, Canada, was performed. FOS were used to measure beam deflections, curvatures, and cracking behaviour, providing insight into element stiffness and support conditions. The detailed data set captured was used to evaluate finite element models based on current design approaches. This highlighted how the accumulation of common conservative assumptions can cause deflection predictions more than five times larger than those measured, potentially leading to excess material use in design. Closure strips in the RC building were also monitored using a method developed in this work, which was able to capture shrinkage and temperature movement of the floor slabs. The field data demonstrated that experience based design approaches appear to be overly conservative, suggesting that further research into closure strips could lead to significant cost reductions if design processes are refined. However, the instrumentation setup developed to monitor closure strips in this study requires durability improvements, as four out of five transducers installed were compromised on site.

abstract: PhD


title: Microstructural Evolution and Hardening of Zr-2.5Nb-0.5Cu Spacer Material under Irradiation

contributor:
Yao, Zhongwen
Daymond, Mark
Mechanical and Materials Engineering

subject: Zr-2.5Nb-0.5Cu Irradiation Microstructure Hardness

abstract:
Zr-2.5Nb-0.5Cu alloy is considered as a potential replacement of the current Inconel X-750 alloy for future spacer installations in CANDU® reactors. They are designed to be placed in the annular space between pressure and calandria tubes to support the pressure tube and prevent it from coming into contact with the calandria tube. During their service lifetime, they are exposed to a high flux of fast neutrons and multiple-directional loads. Therefore, it is important to study the effect of irradiation on the microstructure, microchemistry, and mechanical property of this alloy. In this dissertation, the effect of ion irradiation, heat treatment, alloying elements, pre-existing crystal defects on the microstructure and irradiation hardening was investigated to help us have a better understanding of this alloy before its application.
Chapters 1 and 2 present a general introduction to the current investigated material and a literature review to previous related studies. Characterization of the microstructure and precipitates of the as-received material is presented in Chapter 3. Three types of microstructure and three types of second phase particles are detected in the as-received material. A comparison between annealing in TEM thin foils and bulk material is displayed in Chapter 4. The change of microstructure and precipitates is significantly slower in TEM thin foils than in bulk material, due to the presence of the foil surfaces. Chapter 5 reports the precipitate stability in the three types of microstructure under heavy ion irradiation. The starting microstructure shows a remarkable influence on the precipitate stability; the precipitates are more stable in the microstructure with a high density of point defect sinks. Chapters 6 and 7 cover the impact of alloying elements Nb and Cu on the loop formation and hardening in Zr alloys under self-ion irradiation. The existence of Nb and Cu exhibits a significant influence on the loop density and Burgers Vector of loops obtained, as well as ω precipitation and subsequent hardening behaviour. In Chapters 8 and 9, pure Mg was used as an analogue of Zr to provide additional insight into the influence that crystal internal defects, such as grain boundaries and gliding dislocations, have on the loop formation during irradiation. Noticeably different loop formation behaviour was observed in the vicinity of a grain boundary under electron irradiation. The pre-existing dislocations also displayed a noteworthy impact on the loop formation.

abstract: PhD


title: The Pilgrim Trust: A History of a "salvage corps" and its Efforts to Preserve the Image of the Nation during Britain's Mid-Twentieth Century

contributor:
den Otter, Sandra
History

subject:
Britain
British History
Charity
Philanthropy
Unemployment
Second World War
World War II
Social Survey
Culture
Art
Heritage
Christianity
Citizenship
Community
Nation
England
Conservative
Britishness
Preservation
Restoration
Countryside
Social Welfare
Welfare State
Voluntary Sector
Modernity
Twentieth Century
Pilgrim Trust
Church of England

abstract:
To know the history of the Pilgrim Trust is to also know Britain’s response to several of its greatest challenges of the twentieth century. Still in operation today, the Pilgrim Trust directly engaged at both national and local levels with some of the major events that we consider to define modern Britain, namely the unemployment of the 1930s, the Second World War, and the debate concerning the national character. As a charity it is perhaps most well-known for sponsoring the unemployment study Men Without Work, funding the Arts Council of Great Britain’s predecessor the Council for the Encouragement of Music and the Arts, and assisting in the preservation of some of the country’s most iconic architecture through restorations and pictorial records such as the Recording Britain series. However, a close reading of the Trust’s archive reveals a much more complex and intriguing history of an association of elite men operating at the highest national level with ample funds attempting to come to the “rescue of the things that mattered in our country” as a self-defined “salvage corps.”
This thesis is not solely a history of a charity from 1930 to 1960, but also a case study for social and cultural histories of Britain. It examines how the charity interacted with consequential debates on matters such as charity law, unemployment relief, the voluntary sector in the welfare state, church and state relations, national character, and modernity. It also situates the Pilgrim Trust within the larger historiography on community, citizenship, nation, welfare, and heritage to argue that the Pilgrim Trust was an invisible hand in promoting an insular, rural, and nostalgic image of Britain as stewards of the nation.

abstract: M.A.


title: Borderline Cinema

contributor:
Lord, Susan
Cultural Studies

subject:
Brazil
Cinema
Latin America

abstract: The term ‘Borderline Cinema’ may sound strange at first, even for scholars and film aficionados. It may also sound like something unprecedented, modern, a result of the changes and re-adaptations in the film industry that happen through the advances of digital media and new advertising markets. The term connotes a range of possibilities, from national borders to lines between cinema and other forms. In recent years, driven by the industrialization process and the rapid changes in digital technology happening around the world, new formats of film productions have emerged. One of these new production formats is Borderline Cinema. This type of cinema has existed for years specifically in the Brazilian suburbs, yet it remains largely unknown and marginalized. The process of creating a Borderline production involves more than technical knowledge, but also a social, political and economic conjuncture which is intrinsically linked to the history of Brazilian cinematography. Despite being marginalized by the mainstream film market, Borderline filmmakers are not entirely excluded from having access to cameras, media, and technology. This creates a form of social engagement with global and local cultures. Nestor García Canclini (1995) and Stuart Hall (2000) define this relation as a form of cultural hybridity that is capable of forming new spatial and social relationships, as well as creating new types of production models. With the implementation of the incentive law mechanisms in the 1990s, Brazil boosted its film production in the country and created new formats for the sponsoring of cultural activities. Once invisible, Borderline Cinema started to gain attention from the market, which was interested in promoting festivals and debates around these films. These changes raised questions, such as what are the incentives behind the promotion of Borderline Cinema festivals? Is the scenario for this type of film finally being legitimatized in Brazil? After the establishment of incentive laws mechanisms for the cultural sector in Brazil, the country was involved in a conjuncture where the cultural production is directly associated with marketing strategies and commercial appeal, placing Borderline Cinema in a critical position that needs to be analyzed and studied.

abstract: M.A.


title: From Magazines to Twitter Memes: The Visual Methods of Animal Activist Social Movements 1860-2018

contributor:
Hand, Martin
Sociology

subject:
Social Movements
Visual
Animal
Activism
Sociology

abstract:
This thesis aims to explore the evolution of social movements against animal performance, leading to its current social and political momentum. By mapping the historical trends of the activist campaigns, this thesis will explore the public attitudes and practices that have influenced the messaging employed by social movement organizations within the movement. The theoretical examination of this thesis is threefold, situating animal performativity, and the opposition to it, within extensive existing literature on social movements, animal/human sociology, and visual studies.

	Through exploratory historical analysis, this thesis will critically examine discursive developments in the movement and the sites of production and circulation as they adapt to new technological forms. I have accomplished this exploration by conducting discourse and content analysis on archetypical images that have been created by activist organizations. Through this analysis, I propose that the majority of visuals used within the movement can be divided into four distinctive themes, three of which remain reliably consistent during the past 150 years. The thesis then explores the technological innovations that have affected the imagery of the movement and audience reactions to new forms of representation.

	This thesis concludes by arguing that the social movements against animal performance has consistently adapted to its time while remaining true to its original themes and messaging. It has taken advantage of changing social attitudes rather than improving forms of image capturing and circulation. While behind-the-scenes footage may be eye-catching, it is the ability of the movement to capitalize on tangential social concerns and incorporate broader animal welfare into concerns that has remained the most consistent strategy.

abstract: M.A.


title: Induction of Immune Tolerance to Hexosaminidase M Using Rapamycin and Prednisone in the scAAV9-HEXM Gene Therapy Treatment of Sandhoff Disease

contributor:
Walia, Jagdeep
Biomedical and Molecular Sciences

subject:
Gene Therapy
Immune Tolerance
Sandhoff Disease
Rapamycin
Prednisone

abstract: Sandhoff disease (SD) is a neurodegenerative disorder caused by the toxic accumulation of GM2 gangliosides in the brain. This is due to a deficient enzyme, β-hexosaminidase A (HEXA), involved in the catabolism of GM2 gangliosides. A recently constructed isoenzyme analogous to HEXA, called Hexosaminidase M (HEXM), can efficiently catabolize GM2 gangliosides, while its gene can be compactly packaged into the self-complementary adeno-associated viral vector serotype 9 (scAAV9). Previous gene transfer studies have shown a significant survival benefit of scAAV9-HEXM in the hexb(-/-) knockout SD murine model. However, subsequent analyses revealed that scAAV9-HEXM has the potential to provoke an immune response against the expressed human HEXM product. This undesirable immune response can prove to be an obstacle for the long-term treatment efficacy, especially in individuals who lack the native HEXA protein (e.g., in infantile forms of the diseases). We hypothesized that suppressing the immune system will allow the body to tolerate the scAAV9-HEXM treatment and the newly-produced HEXM protein. Rapamycin (R) and prednisone (P) are immunosuppressants with a regulatory T-cell sparing effect, and both are used clinically to suppress cytotoxic immune responses. In this study, the administration of R and/or P in conjunction with scAAV9-HEXM was studied in SD mice. It was observed that administering both R and P long-term with scAAV9-HEXM demonstrated a significant reduction in antibody and IFN-g T cell responses to HEXM. which persisted after R&P administration ceased. This successful use of the R&P and scAAV9-HEXM resulted in significantly higher hexosaminidase enzyme activity levels in serum, reduced GM2 accumulation in the brain, and an increase in biodistribution of the vector in the liver. These mice also showed an extended lifespan beyond that achieved by the gene therapy in the absence of immunosuppression, with mice living for up to 7 weeks longer. The outcomes of this study may provide a proof-of-concept toleration immunosuppression regimen for long-term efficacy of not only the scAAV9-HEXM treatment, but also other gene therapy studies using AAV.

abstract: M.Sc.


title: Investigating the Predictors of Women’s Future Intention to Accept and Use Smartphone Applications for Type 2 Diabetic Self-Management in the Kingdom of Saudi Arabia

contributor:
Almost, Joan
Nursing

subject: Diabetes Management in Saudi Arabia

subject: Perceiving Usefulness of Smartphone Applications among Saudi Women with Type 2 Diabetes

subject: Investigating Intention to Accept and Use Smartphone Applications in Diabetes Disease

subject: Smartphone Applications Interventions for Type 2 Diabetes

subject: Type 2 Diabetes in Saudi Women

subject: Self-Management in Saudi Arabia

abstract:
Background: Diabetes is one of the most prevalent chronic diseases in many societies, and the Kingdom of Saudi Arabia (SA) has one of the highest incidence rates globally. In SA, close to 28% of women have been diagnosed with Type 2 diabetes. Saudi health authorities have established self-management programs in primary healthcare centres (PHCs) to educate patients, but these programs have many shortcomings. A new approach has emerged in the diabetes field using smartphone technology to enhance patient self-management. While studies have focused on evaluating the use of smartphone technologies among patients with chronic diseases, no study has examined the acceptance of smartphone applications among women with Type 2 diabetes in SA.
Purpose: To test a theoretical model examining selected predictors (performance expectancy, effort expectancy, social influence, patient-centred factors) of the future intention to accept and use smartphone applications for Type 2 diabetic self-management among Saudi women.
Method: A descriptive, cross-sectional survey design was conducted with a sample of 98 women with Type 2 diabetes in public PHCs in Jeddah, SA. Participants were asked to complete a pen and paper questionnaire including smartphone use, modified Unified Theory of Acceptance and Use of Technology Scale, and scales measuring patient-centred factors.
Result: SA women in this study intended to accept and use smartphone applications for diabetes management in the future. The current use of smartphone applications in diabetes management influenced their intention to accept and use diabetes applications. Testing of the theoretical model found 32.1% of the variance in participants’ intention to accept and use smartphone applications to manage Type 2 diabetes was explained by the six predictors. However, only effort expectancy was a significant predictor in the final model.

abstract: MNSc.


title: EPB Excavation and Conditioning of Cohesive Mixed Soils: Clogging and Flow Evaluation

contributor: Geological Sciences and Geological Engineering

subject:
Earth Pressure Balance Machine
EPB
Mechanized Tunnelling
Mechanised Tunnelling
EPB Soil Conditioning
Clogging
Flow Behavior
Cohesive Soils
Tropical Residual Ground
Tunnel Excavation
Shield Tunnelling

abstract:
When shield tunnels are being excavated along varying geological conditions, it is essential to understand the behaviour of the material being excavated, as it influences excavation speed and ground stability, in addition to other operational issues. For an Earth Pressure Balance Machine (EPBM), this requirement is increased because the excavated material, combined with the rotation of the machine screw conveyor and the thrust of the hydraulic jacks, is responsible for holding the pressure ahead of the machine. For this system to function, this material needs to maintain certain engineering characteristics. In the absence of those key target properties, additives should be mixed with the excavated soil in front of the machine or in the conveyor system, a process called ground conditioning.
There are numerous bodies of research concerning EPBM conditioning that mostly focus on either sandy or clayey soils, with relatively little published information regarding mixed ground. Terrains originating from the tropical weathering of rocks present these mixed ground characteristics. EPBM have excavated this type of ground in many areas around the world.
The aim of this thesis is to investigate and characterize this type of terrain, exploring the particularities regarding its excavation by EPB shields, including the conditioning of those materials. The focus is on cohesive mixed soil, thus restraining the topic. This research includes two main subjects: the assessments of clogging behaviour and flow behaviour of cohesive mixed soils for EPBM excavation, drawing a parallel between them whenever possible.
A laboratory routine was developed for investigating and characterising these mixed soils and their flow and clogging tendencies. Soils were assembled in the laboratory, allowing control of all the inspected elements. Several conclusions related to the clogging potential and flow behaviour could be achieved by changing certain variables: clay mineral, clay fraction, grain size of the sand fraction, water content, foam, and polymers.
This laboratory routine and some of the achieved conclusions can be also applied to materials other than cohesive mixed soils. Some considerations for future work are provided, foreseeing the need for a future correlation and validation of the assumptions here made with real tunnel drives.

abstract: PhD


title: Attack on the Geneva Conventions? A Principled Review of the US Military Strike on the MSF Trauma Centre in Kunduz, Afghanistan

contributor:
Lamp, Nicholas
Law

subject:
Law of Armed Conflict
International Humanitarian Law
International Criminal Law
War crime

abstract:
In October 2015, the US military attacked a trauma center operated by the global aid agency Médecins Sans Frontières in Kunduz, Afghanistan.  Because medical facilities are protected pursuant to international law from being made the object of attack, the incident was widely condemned in global public discourse as a war crime.  The US military dismissed this characterization with one single sentence, asserting that “the label ‘war crimes’ is typically reserved for intentional acts” and that this attack does not qualify because the trauma center was not attacked “intentionally”.  Demands to allow for an investigation by an independent, international fact-finding commission went unheeded by the US military, which instead performed its own internal investigation.  The decision not to initiate criminal proceedings against any personnel involved in the attack prompted further public outcry.  The discord created by various competing narratives and perspectives involving this attack remains largely unresolved.
	This thesis engages in a thorough and detailed analysis that is founded upon identified legal principles to evaluate whether the attack constitutes a war crime.  After concluding that the attack is not a war crime because the required mental element is not established, the examination goes on to assess whether personnel involved in the attack nonetheless violated applicable international law.  The assessment of compliance with the law of armed conflict (LOAC) concludes, contrary to the findings of the official military investigation, that the LOAC rules of distinction and proportionality were not violated, though specific personnel violated the requirement to take feasible precautions in the attack.
	Existing narratives related to this attack typically are not founded upon a recognizable legal analysis or, as is the case with the official military investigation, are built upon an inaccurate or incomplete legal analysis.  This is so even though these narratives invoke inherently legal terminology such as “war crime” and “LOAC violation”.  An analysis based on identifiable and verifiable legal principles can provide a foundation for the effort to reconcile the various competing narratives and perspectives and perhaps assuage the discord that persists today.  The detailed legal analysis conducted in this thesis is intended to provide such a foundation.

abstract: LL.M.


title: Between Universalism and Cultural Relativism: A Justification for Universality in the Application of International Human Rights to Contemporary Africa

contributor:
Aiken, Sharry J.
Law

subject: Human Rights

subject: International Human Rights

subject: Standards

subject: Norms

subject: Universalism

subject: Universality

subject: Relativism

subject: Cultural Relativism

subject: Unity in Diversity

subject: Modernization Theory of Human Rights

subject: Modified Modernization Theory of Human Rights

subject: Ideological Relativism

subject: Public Policy Priority Relativism

subject: Transformatons

subject: Change

subject: Morality

subject: Law

subject: Sui Generis

subject: Human Rights Minialism

subject: Thin Morality

subject: Homeomorphic Equivalents

subject: Secular Morality

subject: Human Rights Treaty Ratification

subject: Group Rights

subject: Individual Rights

subject: Balance

subject: Harmful Cultural Practices

subject: Female Genital Mutilation

subject: FGM

subject: Surgery

subject: Modification

subject: Cutting

abstract:
When the United Nations moved to promulgate the ICCPR and ICESCR in 1966, the world seemed set on a path to an international regime of human rights. This regime, it was hoped, would provide sovereign nation-States with the necessary legal and political language with which to censure and/or regulate any State conduct deemed inimical to the standards set out in these human rights instruments. Yet, since the promulgation of these instruments, we still have as  many reasons for concern about the achievements of the IHRs regime as we have for optimism. Part of this concern arises from the relativist challenge to the assumption that IHRs are universal.

In this thesis, I look at the universalism versus cultural relativism debate in the context of post-colonial Africa, and seek to advance three independent claims. First, contrary to the conventional relativist view that contemporary African societies are structurally communal societies, I claim that these societies are, in fact, modern nation-States. Based on this claim, I argue that IHRs standards are culturally suitable for application to modern Africa, pursuant to the modified modernization theory. Second, I contend that the extant pleading for cultural relativism in Africa is as much fixated on the relevance and significance of precolonial African structures as it is based on reified assumptions about the relative roles of the human individual and community. Finally, I proffer a claim for a theoretical justification for universality and, thus, the application of IHRs standards to all modern nation-States, including those in Africa.

I, therefore, approach this debate from both practical and theoretical perspectives. Practically, I argue that the adoption of the Western models of socio-political governance and capitalism has structurally and socially transformed pre-colonial African societies into modern nation-States, thereby necessitating the adoption of human rights as both a prophylactic and a remedial response to the threats of modernity. I, further contend that a more compelling moral justification for the universality of human rights standards lies in understanding the nature of human rights as “sui generis universal legal and moral rights.” This contention serves to overcome the limitations inherent in contemporary minimalist morality theories
which, in my view, under prescribe both the scope, and validity of human rights by reason of reference to specific cultural, philosophical, political and theistic justifications.

abstract: PhD


title: Qualitative evaluation of an anti-stigma intervention to reduce the impact of stigma in individuals with mental illness

contributor:
Milev, Roumen
Neuroscience Studies

subject:
Mental Illness
Behavioural Modification
Stigma
Mood Disorder
Anxiety Disorder

abstract:
Objectives: To evaluate the effectiveness of a group-based, psychoeducational and behavioural modification intervention, Overcoming Stigma in Mood and Anxiety Disorders, in reducing the impact of mental-illness-related stigma. A secondary objective was to explore the nature of behavioural changes that follow the intervention.

Methods: Qualitative data was collected from focus groups and coded to generate themes. Thematic analysis was used to develop and modify a Theory of Change model for future program development.

Results: Seventeen themes were generated. The themes were exploratory in nature and were categorized under the following sections: living with mental illness, program evaluation, and behavioural change.

Conclusion: The results of this study have been encouraging. Qualitative understanding of this anti-stigma intervention can assist with future program development. Understanding the nature of behavioural change can guide development of impactful quantitative surveys for use in a broader evaluation. Enhanced evidence-based anti-stigma interventions can help individuals overcome self-stigma in order to have a full and meaningful life.

abstract: M.Sc.


title: Cross-Movement Coalitions and Sexuality Politics: How activists resist political homophobias in East Africa

contributor:
Little, Margaret
Epprecht, Marc
Political Studies

subject:
Political Homophobias
Sexuality Politics
Cross-movement coalitions
transnational social movements
African Politics
Comparative Sexuality Politics
Activism under authoritarianism
Uganda
Rwanda

abstract: Sexuality is part of what structures politics. States rely on reproduction to replicate their populations. How sexuality is regulated is political, and it should be considered in political science literature. In recent decades there have been significant changes in rights for lgbt people globally, but also backlashes against them in states where rights have been won and where they have not. These backlashes are referred to as political homophobias, actions states take to dehumanize and police gender and sexual minorities. In this dissertation, I analyze how resistance occurs against these political homophobias, even in contexts where they appear to be highly popular amongst political leaders and the public. Through this analysis, I demonstrate that the perception that political homophobias can be used to gain cheap popularity for a government can be altered. Using literature on cross-movement coalitions, hybrid and authoritarian regimes, and international human rights activism, I argue that activism can change political processes on political homophobia legislation, specifically analyzing Uganda, Rwanda, and Burundi as a shadow case, all East African countries that introduced political homophobia legislation in 2008 and 2009. Political processes produce conditions ripe for political homophobias in Uganda and Rwanda. Tracing decisions from colonialism to independence governing structures, structural adjustment to the HIV/AIDS epidemic, I argue that political decisions on how sexuality should be regulated created conditions to empower those promoting political homophobias in the twenty-first century. Using interviews and document analysis, I track why Uganda and Rwanda did not institutionalize political homophobias, despite the perception that the proposals were popular. I argue cross-movement coalitions coordinating resistance were central to the defeat of the proposals. Cross-movement coalitions use in-depth knowledge of the political system to advise international allies on how best to respond, given domestic considerations, including regime type. I demonstrate there is room to resist political homophobias, even in authoritarian regimes. Political homophobia literature should consider how these proposals interact with other political issues, and how activism can change political calculations about what is politically most advantageous.

abstract: PhD


title: Preparation of Monocrystalline Platinum Electrodes And Their Structural Transformation Upon Electro-Oxidation and Electro-Dissolution in Aqueous Acidic Media

contributor:
Jerkiewicz, Gregory
Chemistry

subject:
electrocatalysis
fuel cell
corrosion
platinum

abstract: Atomic-level understanding of the degradation of platinum (Pt) materials is important for rational design of nanoscopic Pt electrocatalysts for fuel cells. Studies employing Pt monocrystalline (single crystal) electrodes can lead to the understanding of atomic-level degradation. Electrochemistry studies on monocrystalline electrodes require well-ordered and highly reproducible surfaces. Therefore, it is of vital importance to understand, optimize, and control each step of single-crystal growth, orientation, and final preparation in order to obtain accurate and reproducible experimental results. Firstly, in-three parts, we report on the development of experimental methodology that allow one to prepare Pt single crystal surfaces and acquire cyclic voltammetry (CV) profiles for hemispherical Pt(111), Pt(110), and Pt(100) as well as polyoriented monocrystalline Pt (Pt(spherical)) electrodes. Then, we report on the dissolution and structural transformation of Pt(spherical) electrode in 0.50 M aqueous H2SO4 upon potential cycling in the surface oxide formation-reduction region. The potential cycling is performed in the lower potential (EL) – upper potential (EU) range (EL = 0.07 V and 0.90 ≤ EU ≤ 1.50 V) to correlate dissolution and morphology data to EU. The amount of dissolved Pt is monitored using flow injection coupled to inductively coupled plasma mass spectrometry (ICPMS) and structural changes, which modify cyclic voltammetry profiles, are examined using scanning electron microscopy (SEM). In the case of EU ≤ 1.20 V, there is minor dissolution of the (100) and (110) facets, while the (111) one remains stable. In the case of EU ≥ 1.30 V, all facets undergo significant dissolution. Changes in the surface morphology of Pt(spherical) upon repetitive potential cycling in the 0.07–1.50 V range were examined in relation to the number of transients (1 ≤ n ≤ 30000). The SEM images reveal the (111) facet develops pits, the (100) facet uniformly distributed hillocks (pyramids), and the (110) facet columns. We report structural changes for twenty-five basal, stepped, and kinked facets. Their analysis demonstrates that the (531) facet is the least roughened, thus the most stable. The original results reported in this article represent a major contribution to the current understanding of the interfacial electrochemistry and electrocatalysis of Pt materials.

abstract: PhD


title: Numerical Investigation of Mixing Tabs in Multi-Ring Entraining Diffuser in Air-Air Ejectors

contributor:
Oseh, Joshua
Mechanical and Materials Engineering

subject:
ejector
entraining diffuser
mixing tabs
nozzle
mixing tube
CFD
k-e
blockage ratio
Enhanced wall treatment
triangular tab
internal flow

abstract:
This research studied the effect of mixing tabs used in entraining diffusers in subsonic short air-air ejectors. Although numerous studies exist on mixing tabs in nozzles, none was found that placed tabs in an entraining diffuser system used with an ejector. Given that mixing tabs led to improvements at the nozzle, they were analyzed in entraining diffusers for this research.
Numerical studies of tab performance were carried out using two-equation κ-ɛ turbulence models with enhanced wall treatment available in ANSYS Fluent on an ejector obtained from a prior thesis [1]. Only triangular tabs were considered on the ejector. Tab number was varied with 4, 8 and 12 tabs. Increasing tab number from 4 to 8 led to increased diffuser pumping while increasing to 12 tabs led to marginal decrease, although higher than the base case. Addition of 4 tabs led to unchanged overall pumping, while 8 and 12 tabs led to reduced overall ejector pumping performance. Tab blockage ratio was also varied at 1%, 2% and 4% blockage per tab. Increasing blockage ratios was associated with increasing diffuser pumping, but worsened pumping at standoff, however, total pumping was unchanged. A location study identified that the placement of tabs just before the diffuser is not as effective as tabs placed at the nozzle exit for similar blockage ratios. Additionally, tabs placed in the primary flow region were associated with higher back pressure penalties than those in the secondary flow region.

abstract: M.A.Sc.


title: Interstorey Drift Performance of Timber Beam-Hanger Connections

contributor:
MacDougall, Colin
Civil Engineering

subject:
timber connectors
heavy timber
structural testing
beam-hangers
self-tapping screws
glulam

abstract:
This thesis is split into two distinct sections. The first describes the design of a testing setup for applying simulated earthquake loads to a timber beam-hanger connection, and the second evaluates the performance of beam-hanger connections under this loading protocol.

Chapter 2 describes existing testing protocols for subjecting timber connections to cyclic loading. The specific details of the current research are then outlined, including the loading protocol to allow for the application of interstorey drifts, and the details of the two specific beam-hanger connections tested for this research (“dove tail” and “bolted plate”). The structural design of a testing frame is then described and the final product of a steel wide flange section, W460x128, with 10mm plates is detailed. A test was then completed to evaluate the performance of the new testing frame. It was determined that the frame performed adequately by ensuring that the deflections incurred during the loading are primarily experienced by the connections.

Chapter 3 describes the laboratory testing of beam-hanger connections under applied interstorey drift deflections. The performance of the connectors was evaluated and it was determined that the Ricon Prototypes exhibited a combined tension and shear fracture of the collar bolts at an average shear of 210 kN and a rotation of 1.33°. The Megant connections failed due to combined tension and pull-out failure of the wood screws, and sustained higher shear, moments and rotations than the Ricon Prototype connections. The interstorey drift values at failure were also compared to the maximum interstorey drift value from the National Building Code of Canada (2.5%) and it was observed that the Megant 310x150 and 550x150 are the only connections that surpassed this value.

abstract: M.A.Sc.


contributor:
Helland, Janice
Art History

subject:
design reform movement
nineteenth-century design history
botanical illustration
Sarah Drake
John Lindley
William Dyce
Richard Redgrave
Christopher Dresser
Owen Jones

abstract:
“Art Botany in Nineteenth-Century Design Reform, 1830-1865” investigates the relationship between developments in botanical morphology and the increasingly codified principles of design reform, the state-sponsored movement to improve the competitiveness of British manufacturing by establishing design as a professional field. The literature of design reform tends to conclude that the movement’s main aim was to raise the quality of manufactured items and improve consumer taste. However, my study builds upon the few analyses that contend the theory of design reform became integrated into the principles of natural philosophy and industrial art, which were then folded together into a uniquely nineteenth-century conception of the vital affinities between natural and industrial ideals, a world in which the design principle “form follows function” is connected to botanical science and idealist philosophy.
My thesis brings together the natural philosophy of design together with its material objects. While reformers aimed to produce objects that were ideal, based on a priori patterns or types, their designs were also meant to be popular and to do concrete work in the social realm. I investigate this tension between the ideal and the real by drawing upon dialectical models of material culture to examine four objects in relation to the stated aims of design reform and within the context of nineteenth-century natural science and liberal ideologies.

abstract: PhD


title: Exploring Students' Internal Motivation for Engineering Creativity: Creative Confidence and the Arts

contributor:
Strong, David S.
Mechanical and Materials Engineering

subject:
Creativity
Motivation
Engineering education
Creative confidence
Creative arts
Mixed methods
Student perceptions

abstract:
This study used a mixed methods approach to investigate undergraduate engineering students’ internal motivation for engineering creativity and student attitude and understanding of creativity in engineering and the arts. Using an ex-post facto design, students’ engineering creativity self-efficacy, creative personal identity, creative growth mindset, and tolerances of judgement, the messy unknown, and the first step were measured. These elements were compared across gender, year of study, engineering discipline, problem-solving preference, and creative confidence, as well as frequency and duration of arts involvement, prevalent arts activities throughout time, and performance experience. A survey instrument was created, including the development of new scales. A mixed methods pilot study was conducted to improve it. It was then distributed to undergraduate students at nine Canadian engineering institutions, with 269 respondents. A qualitative phenomenological methodology was implemented, investigating student perceptions of creativity in engineering and art and any benefit of arts in creative development through 21 individual interviews.
Results from the survey instrument suggested that students possess generally high creativity self-efficacy and tolerance of fears hindering creativity, and neutral creative mindset and creative personal identity. Thus, students may be internally motivated to engage in engineering creativity. Students involved in arts displayed higher creative personal identity, while male students had higher creative self-efficacy and tolerance of fears than female students. Students who preferred open-ended problems displayed higher instances of internally motivating characteristics than those who preferred closed-ended problems.
Qualitative results indicate that students define engineering creativity as problem solving, while artistic creativity was described in terms of emotional response. Students identified barriers to creativity, including the fears of judgement, failure, and doing things differently, and lack of time, lack of opportunity, and lack of value from instructors. The arts were identified as useful in overcoming internal barriers to creativity, as well as development of self-confidence, perseverance, different perspectives, and communication skills.
Universal understanding of engineering creativity would aid in combating student misconception and provide a foundation for assessment. Instructor support is key in fostering creativity of undergraduates. Creativity education should be implemented, and opportunities for creative engagement without risk of failure adopted in engineering education.

abstract: M.A.Sc.


title: Examining the Mechanisms for Dismissal of Frivolous and Abuse of Process Claims in the International Investment Regime: a Case of Failed Legal Transplant?

contributor:
Karton, Joshua
Law

subject:
Investment arbitration
claims
mechanisms for dismissal
frivolous and abuse of process claims

abstract:
Investor-state arbitration is in a phase of reform. One aspect of this reform process is that the recently-negotiated treaties and updated arbitration rules include mechanisms for the early dismissal of frivolous claims (including those manifestly without legal merit and those unfounded as a matter of law). Some ISA tribunals have also, without an express provision empowering them and only in narrow circumstances, dismissed investors’ claims as an abuse of process.
The mechanisms for early dismissal of frivolous and abuse of process claims in ISA vary across investment treaties and arbitration rules, but they all share a fundamental characteristic borrowed from domestic legal systems: that the same tribunal empowered to rule on the merits is also charged with identifying such claims and curtailing them early in the arbitral process. The system of investment arbitration, however, radically departs from the structural organization of the domestic legal systems, with their integrated judicial hierarchies, application of precedent, judicial review of administrative actions, and traditions of job tenure and other career safeguards that protect judicial independence. The comparative law literature teaches that legal transplants often fail when attention is not paid to the structural and doctrinal context of the recipient legal order.
This thesis situates the dismissal of frivolous and abuse of process claims within the broader context of the structures of the international investment regime and the incentives those structures create for decision-makers. It shows that the outcome of these factors is that arbitrators utilize and will continue to utilize the mechanisms for early dismissal only in overly narrow circumstances. This thesis then examines alternative mechanisms that may be used to identify and deter frivolous and abuse of process claims, and proposes a mandatory evaluative conciliation procedure prior to arbitration as the effective option to facilitate early dismissal of frivolous and abuse of process claims. This pre-screening mechanism would provide opportunities for assessment of claims in a flexible and non-adversarial context, and would take the gatekeeping function out of the hands of arbitral tribunals, which are not well placed to perform it.

abstract: PhD


title: Phenomenological Studies and Analysis Techniques to Search for Light Dark Matter With NEWS-G

contributor: Physics, Engineering Physics and Astronomy

subject:
Dark Matter
NEWS-G
Low-mass WIMPs
Fano Factor
Neutrino Floor
Neutron Capture

abstract: The NEWS-G collaboration uses gas-filled Spherical Proportional Counters (SPCs) to search for low-mass dark matter. As one of several competing collaborations pushing the low-energy frontier of particle detection technology, NEWS-G now is preparing for an exciting new experiment at SNOLAB. In addition to an upgraded detector, an improved understanding of SPCs, and sophisticated analysis techniques are needed to continue the search for dark matter. This thesis presents work done to address several of the outstanding challenges that NEWS-G must face. The possibility of measuring the ionization quenching factor of gases with a neutron capture experiment is explored, but ultimately ruled-out. A likelihood analysis framework is implemented for NEWS-G, and validated through a case-study of the neutrino floor. Finally, the COM-Poisson distribution is proposed as a novel tool to model ionization statistics at the single electron-regime, and to assess the impact that the Fano factor may have on direct detection experiments.

abstract: M.Sc.


title: The SimGen Prototyping Tool: Facilitating Generation of 3D Simulations

contributor:
Dingel, Juergen
Computing

rights: Attribution-ShareAlike 3.0 United States

subject: DSL SimGen Simulation Unity modeling prototyping 3D rover

abstract:
Simulation and 3D animation have become a critical aspect of developing and testing hardware and software systems throughout many domains. The availability of compu- tational power, and development of techniques and tools has made 3D environments prevalent on even the most common devices. Embedded systems which control hard- ware from alarm clocks to rockets are increasingly starting to be developed using a Model Driven Development (MDD) approach. MDD currently suffers from a lack of supporting tooling and can stand to greatly benefit from the integration of simulation. This presents an opportunity for a tool that can quickly produce a 3D simulation and animation environment, and easily connect with generated applications to test these embedded systems.
Significant parts of the process of creating simulations in Unity, one of the most powerful game engines in today’s market, were automated through the use of a Do- main Specific Language (DSL). Scripts generated according to the specification of the user expressed using the DSL, are used to automatically create a fully functional simulation environment. The simulation can be deployed on numerous platforms, and programs written in a variety of languages can be connected to it. The use of TCP connections allows for interactions of various programs across a network with the simulator. A fully configurable communication protocol enables users to connect multiple applications to various objects within the simulation. The produced tool, SimGen, is explained in detail and its use is demonstrated with a series of examples throughout this thesis.

abstract: M.Sc.


title: Cryogenic Alkali Halide Scintillators for Rare-Event Searches

subject:
Scintillators
Alkali Halide
Rare-Event Searches
Dark Matter Searches
Cryogenic

abstract:
Rare-event searches such as the direct detection of dark matter require very low backgrounds, as well as large volumes of material because of the low rate of signal. Scintillators are an excellent particle detector candidate for such searches because of the flexibility in material choice for the selection of different signals, as well as the possibility of purification to remove backgrounds. Cryogenic scintillation detectors employ further background discrimination by utilizing the signal of heat input when a particle interacts in the material. The ratio of light emitted to detected heat can be used as a selection criteria to remove backgrounds such as gamma radiation.

DAMA/LIBRA is a dark matter direct detection experiment that claims the detection of an annual modulation signal using thallium-doped sodium iodide (NaI(Tl)) scintillating crystals that is consistent with a dark matter hypothesis. Many other dark matter direct detection experiments have failed to verify this signal using other materials. One popular idea is to try to verify this signal using the same or similar materials to DAMA/LIBRA, such as alkali halide scintillators to remove any material-dependent assumptions. Several collaborations, such as SABRE and COSINUS, are currently developing experiments using NaI and NaI(Tl) to test DAMA/LIBRA in the near future.

This dissertation will present the ability of a small detector with background discrimination, such as a cryogenic scintillation detector, to detect a modulating signal. These simulations indicate that even a relatively small exposure could investigate an annual modulation signal if the background was reduced.
Towards the development of such a detector, this dissertation will also present measurements done using an optical cryostat at Queen's University to characterize the light emission characteristics of alkali halide crystals, including cesium iodide (CsI), NaI, and NaI(Tl) at low temperatures. Light yields and scintillation time constants are reported, as well as the ratio of light emission between alpha and gamma excitations as a function of temperature, a measurement available to our experiment because of a high light collection efficiency and novel data processing. It shows that CsI, NaI, and NaI(Tl) have sufficient light yield at low temperatures for use in a cryogenic scintillation detector to further understand the DAMA/LIBRA modulation claim.

abstract: PhD


title: Modelling of Hard Rockmasses with Non-Persistent Joints to Assess the Stress Induced Damage of Deep Excavations

subject:
Deep Tunnelling
Hard Rockmasses
Brittle Failure
Excavation Damage Zone (EDZ)
Numerical Modelling
Finite-Discrete Element Method (FDEM)
Discontinuum Modelling
Strain Bursting

abstract:
Brittle fracturing within low confinement environments is the dominant failure mechanism of hard rockmasses under high magnitude in situ stresses around underground excavations. With an emphasis on the behaviour of slightly to moderately jointed rockmasses, this body of research investigates the influence of pre-existing joints on the fracturing mechanisms occurring and the excavation induced damage surrounding an underground opening. To achieve this goal, advanced numerical approaches involving the generation of discontinuity networks and discontinuum analysis methods were employed.

Discontinuity geometrical data obtained from laser scans of an unsupported tunnel served as input parameters for the generation of discrete fracture networks (DFNs), and the material properties of the massive granite encountered at the Canadian Underground Research Laboratory (URL) were used to develop a grain-based numerical model using the distinct element method (DEM) enriched with DFN geometries. The created synthetic rockmass models (SRM) were used to determine the effect of pre-existing structure on the driving failure mechanisms. Field observations from the URL were also used to calibrate a tunnel scale model by applying the finite-discrete element method (FDEM) to simulate the tunnel response within a massive rockmass, and serve as the reference model for subsequent analyses by integrating DFNs.

SRM results provided useful insights and an S-shaped strength envelope derived from bi-axial tests revealed the role of low confinement in brittle fracturing. From the same tests, evaluation of the rockmass modulus resulted in a semi-empirical equation for estimating it based on discontinuity parameters. Following the validation of the ability of the FDEM method to capture brittle processes observed at the URL, results from the jointed models demonstrated the influence of discontinuities on the material response during an excavation. The strong impact of the joint network geometry and field stresses on the excavation induced damage and overall stability of an opening was revealed. Regarding strain bursting phenomena, the ability of discontinuities to dissipate and/or enhance them was examined. The capability of this approach to capture the complex energy storage and energy release, and fracturing mechanisms was demonstrated along with its potential practical application in engineering design.

abstract: PhD


title: Characterization of the interactions of a lignostilbene alpha-beta dioxygenase with both stilbene and carotenoid substrates

contributor:
Loewen, Michele
Allingham, John
Biomedical and Molecular Sciences

subject:
molecular biology
structural biology
enzymes
carotenoids
stilbenes
dioxygenase

abstract: As one of many evolutionary compensations for immobility, plants synthesize an array of natural products and metabolites which afford advantage against environmental stresses. The utility of these products is exemplified by stilbene and carotenoid-derived metabolites which are important in plant processes such as immune response and protection against UV-light damage. Not limited to plants, these metabolites even play roles in the maintenance of human health as antioxidants and in vision. Stilbene and carotenoid derivatives are generated by a family of non-heme, iron-coordinating enzymes, divided into two functionally distinct sub-families, including lignostilbene cleavage dioxygenases (LCDs) and carotenoid cleavage oxygenases (CCOs). While these enzymes have highly similar structure and identical reaction mechanisms, LCDs and CCOs have widely different substrate specificities, mediated by factors that currently remain enigmatic. To gain insight into these factors, a previously characterized bacterial LCD from the bio-control agent Pseudomonas brassicacearum (PbLSD) was compared to an array of CCOs by amino acid sequence and structural alignments, as well as in silico docking. This yielded several target residues predicted to contribute to substrate selectivity within the binding pocket. These predictions were tested using an in vivo carotenoid-cleavage assay system combined with site-directed mutagenesis. Current results emphasize that the structure of the binding pocket plays a key role in mediating substrate specificities, with potential applications for the commercial production of desirable carotenoid derivatives. Additional work characterizing specificities and reaction products of purified PbLSD-mutants in vitro, by liquid chromatography and mass spectroscopic methods is ongoing.

abstract: M.Sc.


title: The relationship between knee joint shape and function: Implications for pathology and treatment

contributor:
Deluzio, Kevin
Rainbow, Michael
Mechanical and Materials Engineering

subject:
biomechanics
knee
statistical shape model
musculoskeletal model
patellofemoral

abstract: Many patient characteristics can affect joint function; yet the implications of this for musculoskeletal disorders and their treatment are not well understood. A better understanding of these relationships could aid in clinical decision making and make it easier to better tailor treatments to each patient. In this work, methods to enable the study of patient variability were proposed and used to investigate the relationship among patient characteristics, function, and surgical outcomes. A method to remove bias from waveform data using principal component analysis was introduced that could be used to combine motion analysis data from different laboratories, thus enabling multicentre studies and larger sample sizes. In a second study, patient characteristics and biomechanical measures associated with the ability of valgus unloader braces to reduce predicted medial compartment contact forces were identified. The hip adduction moment during unbraced walking was the best predictor of mechanical brace effectiveness. The remainder of this thesis focused on articular geometry, a source of patient variability that has previously been shown to be correlated with joint function and pathology. Here, a framework was proposed that can be used to predict the causal effects of geometry on function. Knee joint geometry was characterized and manipulated through statistical shape modelling and functional effects on knee kinematics, cartilage contact, and ligament forces were predicted using musculoskeletal simulation. This framework was used to examine the impact of knee joint geometry on functional outcomes of simulated tibial tubercle osteotomy, a surgery that realigns the patellar tendon to treat patellar instability. It was found that knees with shallow patellofemoral geometry were much more sensitive to medial/lateral placement of the patellar tendon insertion than those with deep geometry. Finally, the potential to use these techniques to inform clinical decision making through patient-specific modelling was explored in a case study of a tibial tubercle osteotomy patient.

abstract: PhD


title: Investigating the effect of algal blooms on water quality in passive wastewater treatment systems

contributor:
Champagne, Pascale
Hall, Geof
Civil Engineering

subject:
Algal Blooms
Bacteria
Water Quality
Wastewater Stabilization Ponds

abstract: Wastewater stabilization ponds (WSPs) are low-cost, effective and sustainable passive wastewater treatment technologies. However, algal blooms may occur in WSPs under certain conditions, affecting the complex interactions between water quality parameters. This thesis is an investigation on the effect of algal blooms on water quality and treatment performance of a WSP located in a temperate climate. Studies were conducted at a WSP located in southeastern Ontario, experiencing reoccurring excessive algal growth and pH fluctuations, exceeding government regulatory limits. A full range of water quality parameters were monitored for the system and the biochemical dynamics in the WSPs were assessed through multivariate statistical analysis. One study was conducted to provide an enhanced understanding of the relationships between algal blooms, water quality and meteorological factors. Water temperature, pH, DO and NO3- were determined to be the most significant parameters describing the spatial variations in surface algal blooms. A second study examined the seasonal disinfection performance using Escherichia coli, and three novel bacterial indicators, Enterococci, Clostridium perfringens and total coliforms, in the presence and absence of the previously studied algal blooms. Temperature, pH and DO were shown to be significant (p<0.05) factors in disinfection. A long-term assessment of seasonal fluctuations in treatment performance and water quality was also performed. Removal efficiency of nutrients and bacteria were observed to have strong seasonal fluctuations and water temperature, pH, DO and TP accounted for majority of the temporal variations observed in water quality. This research provides practical knowledge and uncovering key trends and factors involved in algal bloom dynamics and treatment performance, contributing to the continued improvement of WSPs design and performance in temperate climates.

abstract: M.A.Sc.


title: Development of an evaluation framework for eye gaze assistive technology

contributor:
Davies, Claire
Mechanical and Materials Engineering

subject: Eye tracking

subject: Augmentative and alternative communication

subject: Disability

abstract:
Children with complex care needs sometimes have difficulty communicating with their parents, caregivers and teachers. For these children eye gaze assistive technology can be used to facilitate communication. The objective of this research was to enhance the evaluation process of eye gaze assistive technology through development of an evaluation framework. A systematic review was completed that aimed to explore eye gaze assistive technology outcome measures for children and youth with complex disabilities. Outcome measures as well as environmental and personal factors were mapped to the World Health Organization’s International Classification of Functioning, Disability and Health framework.
The systematic review identified prohibitive costs, technical issues, and personal factors as barriers that impeded technology uptake. To begin to address the issues of prohibitive costs and technical issues, a reliability study and usability study were conducted using the low cost Tobii 4C eye tracker with typically developing children and adults. Results indicated that the low cost eye tracker was suitable for assistive technology applications and informed recommendations for device set up and calibration. The usability study also explored the personal factors of fatigue and frustration, by conducting a workload assessment using the NASA Task Load Index. Results indicated that fatigue is the largest workload contributor and that incidences of frustration may be over reported.
The systematic review also identified professional support as the primary facilitator of technology success. It further recommended utilization of Goal Attainment Scaling and the Augmentative and Alternative Communication Therapy Outcome Measures when evaluating eye gaze assistive technology. A methodology was developed for clinicians that promotes the design of a user interface that is both functional and appropriate for the user by using the principles of cognitive work analysis. Findings were integrated into the proposed eye gaze assistive technology evaluation framework, specifically designed to support clinicians. This provides the individualized approach necessary for the heterogeneous population of eye gaze users. Additionally, by reporting outcomes in a standardized format that can be easily interpreted, this will encourage comparison between different users and studies.

abstract: M.A.Sc.


title: Examining the Neural and Cognitive Processes Underlying Typical and Atypical Reading Ability

contributor:
Munoz, Douglas
Kirby, John
Neuroscience Studies

subject:
Neurodevelopment
Reading Ability
Dyslexia
Neuroimaging

abstract:
Although reading is an important and generative skill that is important for a child’s future academic, economic, and social success, it remains controversial how it develops and what leads to reading difficulties. Furthermore, due to the multiple and complex components involved during reading, the neuroanatomical mechanisms that support the behavioral differences of reading ability are currently not well understood. Therefore, the overarching goal of this thesis was to further the understanding of reading and reading difficulties by integrating aspects of their neuroscientific, cognitive, and educational accounts, as illustrated by functional magnetic resonance imaging (fMRI), eye tracking, and speech recording.
To simplify the examination of the processes involved in reading, we focused on naming speed (NS) tasks, in which participants are required to name sets of simple stimuli as quickly and as accurately as possible, because these tasks have been shown to predict concurrent and future reading ability in both typically achieving readers and in poor readers. Using NS tasks, we examined improvements in behavioral performance associated with typical development from childhood to adulthood, and how this differed in children and adults with dyslexia. We also examined how behavioral and neural differences between typically achieving readers and readers with dyslexia were related, and how they were associated with compensatory strategies used by readers with dyslexia to account for their reading disability.
Overall, the findings of the five studies presented in this thesis indicate how combining multiple techniques, such as fMRI, eye tracking, and speech recording, to study reading and reading deficits provides a better controlled, more global view of the processes that are involved and how these processes differ in individuals with reading difficulties. Future research that adopts this multidimensional approach to examining reading difficulties is important because it will not only lead to the optimization of current diagnostic criteria for dyslexia, but also has the potential to lead to the early identification of children who are biologically at risk for developing dyslexia. This in turn has the potential to lead to more effective and appropriate interventions which can positively impact and change the outcome trajectories for those with reading deficits.

abstract: PhD


title: Contested Futures - Traditional Rice as a Keystone of Alternative Agriculture Movements

contributor:
Taylor, Marcus
Environmental Studies

subject:
Agriculture
Agroecology
Global Development
Political Ecology
Traditional Food Systems
Food sovereignty
Traditional Seeds
Agricultural Knowledge

abstract: The Green Revolution reshaped rural livelihoods by introducing new, exogenously-generated, inputs and knowledge. Predicated on enhancing yields and food productivity, this had widespread implications on biodiversity conservation and food security, including the marginalization of traditional crop varieties.  In south Karnataka, India, these conditions provide the context for contemporary rural debates centered on alleviating rural poverty, attending to an epidemic of farmer suicides, enhancing food security, and confronting increasing climate uncertainties.  My research enters this debate by examining the relationship between seed choice, agricultural knowledge and cultivation practices among smallholder rice farmers across three districts in south Karnataka.  Specifically, seed choice serves as a principal lens for elucidating the broader conceptualizations of agricultural development, as well as the knowledge politics therein, across different actors and agricultural movements in south Karnataka.  Informed by a political ecology framework, these debates are investigated through a discursive literature review and fieldwork interviews in the case study location with Government officials, agricultural researchers, NGO representatives, organic entrepreneurs, and farmers.  My research highlights the agricultural knowledge dynamics, rural hierarchies, incentive structures and public-private partnerships that characterize mainstream agricultural development initiatives in south Karnataka.  Next, my research highlights how several local alternative agriculture movements have sought to contest these dynamics by proposing new agroecology-based strategies oriented-around traditional seed varieties.  Finally, my research elucidates the ongoing knowledge politics within these alternatives.  It highlights their commonalities and critical divergences, and examines their respective opportunities and constraints for enhancing rural livelihoods in south Karnataka.

abstract: M.E.S.


title: A Study of Vancomycin-Resistant Enterococci Derived From Wastewater Treatment Plants

contributor:
Liss, Steven N.
Brown, R. Stephen
Environmental Studies

subject:
Vancomycin-resistant Enterococci
Wastewater Treatment Processes
Environmental Antimicrobial Resistance
Enterococcus

abstract: Antimicrobial resistance (AMR) is a growing public health problem and a threat to the sustainability of the global healthcare system. It is not only detected in the clinical setting but also other environments including wastewater treatment plants (WWTPs) which are potential targets for surveillance and points of control for the environmental dissemination of AMR. Vancomycin-resistant enterococci (VRE) are potential candidates as indicator organisms for AMR in water environments. Identification methods for Enterococcus were compared and the groESL locus was the most accurate method. The enterococci/VRE from two WWTPs, a biological aerated filter (BAF) and a conventional activated sludge (CAS) system, from the same municipality collected over 2 years were characterized through quantification, speciation, antimicrobial susceptibility testing, and genomic analysis. The primary effluents (PE) of the two WWTPs were similar in the quantity, species composition, and frequency of AMR of enterococci. VRE were not selectively removed by either WWTP and the BAF system removed enterococci most effectively. Presumptive VRE isolated from the CAS final effluent (FE) included more E. faecium and had increased prevalence of nitrofurantoin resistance and decreased quinupristin/dalfopristin resistance compared to the CAS PE isolates. The BAF FE had a higher proportion of E. faecalis than the CAS FE and a decrease in levofloxacin resistance. The AMR profiles of the isolates after treatment differed from the pre-treatment isolates. Enterococcus isolates (n = 39) were sequenced and were compared with additional genomes from other sources. For E. faecium, wastewater genomes cluster separately from the clinical genomes while, for E. faecalis, wastewater genomes cluster with either clinical or agricultural genomes. Multiple multidrug efflux pumps were detected in the wastewater enterococcal genomes. The majority of virulence genes detected were associated with adhesion, biofilm formation, and capsule formation. Variation in genome size was correlated with the amount of genes associated with the mobilome in E. faecium and E. faecalis. The mobile genetic elements detected were shared among Enterococcus spp. Bacteriophage belonged to Siphoviridae and Myoviridae. Type II CRISPR-Cas arrays were detected in E. faecalis. Understanding the dynamics and characteristics of VRE in wastewater can improve environmental AMR risk assessment frameworks and migitation efforts.

abstract: PhD


title: Understanding the neurobiological basis of mixed-strategy decision-making in health and disease

contributor:
Parr, Ashley C
Neuroscience Studies

subject:
mixed-strategy
decision-making
reinforcement learning

abstract:
During competitive interactions involving multiple agents, such as sporting competitions, the outcome of each
individual’s actions is dependent not only on a historical sequence of their own choices, but on those of their
opponents as well. Success in such rivalries often requires that individuals adopt a mixed-strategy wherein
available actions are chosen dynamically and unpredictably. Action selection in mixed-strategy environments
involves the coordination of widespread neural processes, spanning the cognitive, emotional, and limbic domains. More specifically, choice selection involves working memory, valuation and reward processes,
reinforcement learning, and execution of motor responses.
The three studies in this thesis investigated the neurobiological mechanisms involved in choosing in
mixed-strategy environments, and how these processes change throughout the course of neurodegenerative
and neuropsychiatric disease. In the first study, we examined the human brain network underlying mixedstrategy
decision-making using functional magnetic resonance imaging (fMRI). Using a carefully controlled
paradigm, we compared the network underlying strategic decisions to that involved in choosing in nonstrategic
environments. This study allowed us to gain insight into the specialized cognitive circuitry involved
in choosing dynamically within a strategic context.
In the second study, we asked how dopaminergic transmission affected mixed-strategy decisionmaking
by investigating how degeneration of the dopamine system in Parkinson’s disease (PD) affected
strategic choice patterns. Further, we investigated the hypothesis that cognitive function is deleteriously
affected by dopaminergic medication (levodopa and dopamine agonists) in patients with PD, and whether
genetic mechanisms controlling dopaminergic transmission could explain susceptibility to medicationinduced
cognitive deficits.
ii
In the final study, we examined mixed-strategy decisions in patients with borderline personality
disorder (BPD), a heterogeneous disorder prevalent in adolescent populations. We explored how the core
clinical features of BPD, namely impulsivity and emotional dysregulation, affected mixed-strategy decisions in
adolescents showing the first signs of BPD.
Together, these studies provide a detailed account of how mixed-strategy decision-making is
implemented in the brain, and how the cognitive functions required for choosing in such environments
become affected throughout the course of neurological illness. This work, as a whole, represents a significant
contribution to our understanding of how the brain integrates diverse sources of information to execute
mixed-strategy decisions.

abstract: PhD


title: Functional Magnetic Resonance Imaging of the Spinal Cord/Brainstem and Brain in Women With Provoked Vestibulodynia

contributor:
Pukall, Caroline
Stroman, Patrick
Psychology

subject:
Provoked Vestibulodynia
Pelvic Pain
functional Magnetic Resonance Imaging
Spinal Cord/Brainstem Imaging

abstract:
Vulvodynia (i.e., idiopathic chronic pain affecting the vulva) is a common but poorly understood pain condition, affecting 16% of women in the general population and leading to negative impacts in many life domains, including psychosocial function and reproductive potential (Pukall et al., 2016). An emerging body of research suggests that central factors (i.e., those involving the brain and spinal cord) may play a role in the etiology and/or maintenance of vulvodynia (Pukall et al., 2016).
Functional magnetic resonance imaging (fMRI) studies have indicated that women with provoked vestibulodynia (PVD)—a form of vulvodynia characterized by provoked pain in response to pressure applied to the vaginal entrance—exhibit increased neural activity in response to both genital and non-genital stimulation in cortical areas related to pain modulation (Hampson et al., 2013; Pukall et al., 2005; Sutton et al., 2015; Pazmany et al., 2017). However, despite the fundamental role of the brainstem and spinal cord in descending modulation of pain, no studies have attempted to examine activation patterns in the spinal cord of women with vulvodynia.
The aim of this study was to examine spinal cord and brain connectivity and activation in women with PVD during painful hand stimulation to evoke descending modulation, the process responsible for the descending control of pain involving brain, supraspinal, and spinal structures (Gebhart, 2004). We hypothesized that women with PVD would exhibit altered connectivity in regions of the brain and spinal cord, indicating diminished descending modulation, and would also have greater blood oxygen level dependent (BOLD) responses in regions previously associated with pain processing. The results of this study examining the spinal cord/brainstem revealed alterations in the connectivity and BOLD responses of regions related to pain modulation. Investigation of the brain revealed similar regions of connectivity in women with PVD and control women; however, this study adds to a growing body of research that have found alterations in the fMRI response of these brain regions in women with PVD. Through furthering our knowledge of spinally-mediated pain mechanisms in PVD, this study provides a more comprehensive understanding of the role of central processing in women with PVD.

abstract: M.Sc.


title: Finite Element Analysis of Profiled High Density Polyethylene Stormwater Arches Under Live Loading

contributor:
Brachman, Richard
Civil Engineering

subject:
Stormwater arch
Finite element analysis
Live loading
Shallow burial

abstract: The physical response of a profiled high-density polyethylene stormwater retention arch structure under shallow burial subjected to design truck loading was investigated, with an emphasis on finite element modelling of the soil-structure system. First, three-dimensional, geometric and materially nonlinear finite element analysis was used to model a physical test on an arch specimen prior to burial with the goal to develop and validate a structural model capable of simulating the response of the arch structure up to and past its ultimate limit state. The explicit three-dimensional geometry of the tested arch specimen was measured in detail using a laser scanner, and tensile index tests were carried out to calibrate a viscoplastic constitutive model. The analysis was capable of replicating the measured load-displacement response of the structure up to and past its ultimate limit state governed by buckling. Second, analysis of a previously conducted full-scale physical test of a single arch structure buried with 460 mm cover above the crown and subjected to cyclic design truck loading was carried out. Displacement measured in the first load cycle was notably higher than in subsequent load steps as the arch worked its way into position, which included the densification of the initially uncompacted gravel backfill and soil shear failure underneath the wheel pad. Time-dependent behaviour was noted under constant load holds, particularly during the first load cycle. The validated structural model was used in conjunction with a nonlinear, elastic-plastic soil model to explicitly model the laboratory setup and testing. The model was able to capture the behaviour of cyclic loading, including apparent stiffening of the soil-structure system after the first load cycle. It matched displacements and deformed shape at the start of the nominal design wheel load (71.2 kN) for all load cycles but was unable to match the measured results during constant load holds and at the larger partially factored design wheel load (90.3 kN).

abstract: M.A.Sc.


title: Queer (and) Chinese: On Be(long)ing in Diaspora and Coming Out of Queer Liberalism

contributor:
Morgensen, Scott Lauria
Gender Studies

subject:
Gender
Sexuality
LGBTQ
Chinese
Chinese Canadian
Diaspora
Race
Queer Theory
Critical Race Theory
Non-Binary
Queer Women
Belonging
Queer Liberalism
Queer (and) Chinese
Home
Erotic Autonomy
Queer Diaspora
Queer Asian Diaspora
Asian Diaspora
Queer Asian
Acceptance
Coming Out
Chinese Canadian LGBTQ
Citizenship
National Belonging
Nationalism
Racialization
Racism
Multiculturalism
Sexual
Family
Community
Colonialism
Imperialism

abstract: Being bicultural, Chinese Canadian LGBTQ people face a double jeopardy in navigating a white heteropatriarchal society while striving for acceptance within their own Chinese Canadian communities. My project records the coming out and not-coming out stories of Chinese Canadian LGBQ women and non-binary people in order to interpret their understandings of the process of coming out/not coming out in relation to the formations of sexual, gender, racial/ethnic, and national identities in the context of diaspora. Based on interviews and a focus group conducted in Toronto, Ontario, Canada, this project examines whether home, recognition, Chinese nationalism and familial values are sites of exclusion and if so, how youth reconcile these tensions. This research expands beyond the visibility of gay, bisexual, and queer men within extant social science accounts of Asian diaspora LGBTQ people by focusing on women and non-binary members of Chinese Canadian communities. I employ a queer diasporic approach centering female subjectivity and standards of femininity and masculinity to conceptualize diaspora outside of heteronormative and patriarchal structures of family and community (Gopinath, 2005). I examine diverse points of tension and reconciliation in the narratives of youth who have and who have not experienced “coming out”. The analysis is built from three major insights introduced by narrators to illuminate Chinese Canadian experiences of queer diaspora: the instability of queer (and) Chinese subjectivity; sense of belonging and acceptance; and logics of modernity, progress and queer liberalism as continued racialization, colonialism and imperialism in disguise. I document how tensions among Chinese Canadians regarding sexuality and embracing or resisting change articulate racial and colonial histories and the fraught locations of Chinese Canadians within a white settler state. I argue that histories of racism, colonialism, and migration place Chinese Canadian families in tension with forms of citizenship and national belonging that are defined by historical politics of sexuality. This research is also concerned with the ways in which these histories may inform the location of Chinese communities within contemporary Canadian multiculturalism, which perpetuates whiteness through its embrace of queer liberalism (Alexander, 2005; Eng, 2010; Lowe, 2015; Manalansan, 2003; Shah, 2001).

abstract: M.A.


title: Intellectual Property Usage as a Determinant of Market Structure

contributor:
Zábojník, Ján
Economics

subject:
Innovation
Intellectual Property
Market Structure
Competition
Economics
Patent
Trade Secret
Copyright
Music
Piracy

abstract:
Intellectual property (IP), such as patents or copyrights, forms the basis of economic policy to encourage innovation, creativity, and growth. In this thesis, I show how the strategic usage of IP by rights holders plays a crucial role as intermediary between economic fundamentals, such as public policy or industrial characteristics, and economic outcomes, such as the structure of markets or the pace of innovation in an economy.

Chapter 2 demonstrates the importance of IP strategy as an intermediary in the context of patent–based measures of innovation. In a theoretical model of innovation, IP, and market interaction, I show that citation–weighted patent counts, the most common innovation measure, are generally valid as an innovation proxy only if the profit motive for innovation is complementary to the protection motive for IP usage. Otherwise, observed patenting could decrease in response to changing economic fundamentals even as innovative effort is increasing, and the inferred relationship between economic forces and innovation will be incorrect.

Chapter 3 tests these predictions empirically for the relationship between competition and innovation, an enduring interest of economists and policymakers. Consistent with the predictions of the model, I show that competition and citation–weighted patent counts have an inverse–U relationship, but that competition has a generally negative effect on research and development activity. Therefore, changes in observed patenting only correlate with changes in innovation at high levels of competition, when the likelihood of innovative success is low; otherwise, patent counts diverge from innovative effort and are invalid as a proxy.

Chapter 4 examines the effects of copyright infringement on the market for recorded music. I show that music piracy has a modest negative effect on sales overall, but the size and magnitude of that effect differ across artists and sales format. The differential effects of piracy impact record labels’ optimal IP licensing strategy in the market for music streaming, determining market structure and the balance of market power.

Taken together, the thesis highlights the important role that IP strategy plays as an intermediary between economic fundamentals and economic outcomes of interest, suggesting implications for economic policy and our understanding of innovation and creativity.

abstract: PhD


title: Examining the Influence of Near Wall Hydraulics on the Regeneration and Mobilization of Discolouration Material in a Drinking Water Distribution Laboratory

contributor:
Saulnier, Rain
Civil Engineering

subject: Drinking Water Pipe Discolouration Biofilm

abstract:
Potable water in Canada leaves treatment facilities in pristine quality and excellent condition for both drinking and sanitation.   However, customer concerns related to discoloured drinking water continue to serve as a worldwide issue in urban drinking water distribution systems (DWDS).  Fundamentally, water discolouration is a result of the long-term accumulation of particulate material which is subsequently mobilized due to sudden changes in hydraulic conditions.  Field and laboratory studies have shown that cohesive layers on the pipe wall are adaptive to the respective environmental and hydrodynamic conditions.  The most readily used approach to manage the risk of water discolouration is unidirectional flushing of watermains.  The imposition of an increased hydraulic shear stress erodes these cohesive layers from the pipe wall into the bulk water.

To examine the regeneration and mobilization of discolouration material a full-scale laboratory was designed to simulate the operation of a DWDS.  The laboratory consists of two identical pipe loops comprised of 108 mm diameter PVC pipes, each with a length of 198 m.  All components of the laboratory are located within a climate-controlled chamber to simulate seasonal temperature variation.  The laboratory is fitted with instrumentation to monitor turbidity, flow rate, pressure, and temperature in a real time manner.

Three experiments of duration 40, 80 and 120 days allowed for the growth of cohesive layers under steady-state flow conditions.  Each growth phase was followed by 3 successive 15-minute flushing intervals to erode the layers.  Grab samples for TSS, metals composition and particle size distribution were scheduled throughout each experiment.  Results found that cohesive layers of various strength characteristics developed with an approximate linear increase in turbidity response with increased growth duration.  The strength of cohesive layers was observed to increase with increased growth duration.  The conditioning velocity during each growth phase had a negligible effect on both material accumulation and layer strength.  Turbidity was determined to be a good indicator of total suspended solids and iron in the water.

abstract: M.A.Sc.


title: Applications of Machine Learning in Revenue Management and Routing

contributor:
Nediak, Mikhail
Levin, Yuri
Business

subject:
Dynamic Pricing
Revenue Management
Bayesian Updating
Thompson Sampling
DEA
GIS
Multi-Objective Optimization

abstract: In this thesis, I use machine learning techniques to solve issues in revenue management and public transportation design. The first two chapters relate to problems of revenue management and online learning. The problem of sequential learning and optimization of the demand function has been an important topic in revenue management. Finding the optimal policy faces numerical complexity and is prone to the curse of dimensionality. It is mostly solved using heuristics and restrictive assumptions. In the first chapter, I use a novel non-parametric approach to solving dynamic pricing and learning problems. I develop a flexible method to approximate the optimal policy using polynomial approximation, thus reducing complexity. I make use of the  Bayesian framework to update the probability model and make advances in numerical methods to solve this problem. In the second chapter, I use a machine learning heuristic called Thompson sampling. I improve the performance of the heuristic over short horizons by enforcing the decreasing nature of the demand function in the sampling algorithm. Using a stylized proof, I demonstrate the performance gains associated with this method and show the merits of ordered sampling with Thompson Sampling over short horizons. The last chapter makes use of a machine learning approach called data envelopment analysis (DEA), which I use in designing new public transportation routes in rural regions. I develop algorithms and heuristics to balance cost and equity under multiple objectives. The solution to this project was implemented in the city of Quinte West, Ontario.

abstract: PhD