Theses

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The role of perceptual load and sensory degradation on cross-modal selective attention
    The role of perceptual load and sensory degradation on cross-modal selective attention
    To understand our sensory environment, our perceptual system must employ selective attention; the ability to attend to target information while ignoring distracting information. In the uni–modal domain the main determinant of selective attention success is capacity limitation, where only when processing capacity is taxed by the target (high load; HL) is distraction eliminated (perceptual load theory; PLT). Conversely, data limits while also increasing task demands, do not benefit selective attention as these limits are often driven by sensory degradation (SD) such that placing additional resources towards the target is not beneficial. Investigations of PLT to the cross–modal domain have produced mixed results, and no study has yet directly contrasted the impact of capacity and data limits in the cross–modal domain. The present dissertation focused on examining the impact of Perceptual Load (PL) and SD on cross–modal selective attention, in addition to examining how these factors would interact with the attended modality and individual differences (ID) in attentional control. Experiment 1 used a go–no–go manipulation of PL to show that distractor effects were not reduced at HL compared to low load (LL) condition and instead displayed trends for increased distraction under HL regardless of the attended modality. Experiment 2 used the addition of noise to create SD, and found that distractor processing increased under SD, again regardless of the attended modality. Experiment 1 and 2 used a uni–modal measure of attentional control, and overall both studies did not find a consistent pattern of correlation with cross–modal selective attention, suggesting important differences between the two. Experiment 3 used a single manipulation to create HL and SD conditions in a single experiment, and also found that both HL and SD showed trends of increased distraction relative to LL conditions. Overall the current dissertation suggests that capacity limitations arise at the modality level, and so do not impact cross–modal selective attention. As such, the findings of the current dissertation suggest there is no difference between capacity and data limited conditions in the cross–modal domain. Results are interpreted within a cross–modal selective attention framework.
      
 Understanding barriers to accessing mental health services for newcomers to Canada using Peterborough, Ontario, as an illustrative example
    Understanding barriers to accessing mental health services for newcomers to Canada using Peterborough, Ontario, as an illustrative example
    The quality of an individual’s mental health has a significant impact on their quality of life, as well as on the cost to society. Regular access to mental health services can help mitigate the risk factors of developing mental illnesses. This paper examines barriers to accessing mental health services, using the community of Peterborough, Ontario, as an example. Social, economic, and cultural barriers impact help-seeking amongst immigrants, putting them at a higher risk of developing mental disorders. The social determinants of mental health can be useful when developing policies aimed at improving utilization of mental healthcare services. Policy makers need to first focus on collecting accurate information on the population, and then developing targeted solutions to eliminate barriers such as language and employment that prevent help-seeking in immigrants.
      “Shall we put the heart in now?” A comparative analysis between creature features and their single reel abridgements
    “Shall we put the heart in now?” A comparative analysis between creature features and their single reel abridgements
    Single reel abridgements of commercial feature films are entering moving image archives because home movie collections that contain them are slowly increasing in archival representation. The abridged commercial films occupy a liminal space in between sustained preservation efforts that focus on studio films and the current interest paid to preserving home movies. As a result, the abridged films are being neglected. The films’ liminal status stems from a dearth of information regarding their relationship to the original films and a clear definition of what they are narratively and aesthetically. After analyzing fourteen abridged horror and science fiction films found in the Ryerson Moving Image collection and comparing them to their original counterparts this project finds that the abridged films are heavily altered in terms of narrative, characters, and causality, and should be treated as individual objects instead of derivative works, thus absolving their liminal status.
     "I realized that cops are just regular people" : changing youth attitudes toward the police through community policing
programming.
    "I realized that cops are just regular people" : changing youth attitudes toward the police through community policing programming.
    Existing literature examining youth-police relations has consistently found that willingness to engage with the police is directly influenced by youth attitudes toward the police. Research findings suggest that increasing positive attitudes toward the police among adolescent populations will result in a subsequent increase in behaviours supportive of the police and law enforcement. The current study was a mixed-method evaluation (including survey data and qualitative interviews) of a community policing pilot program designed to increase positive contact between at-risk youth and police officers. The program was effective in positively changing youth attitudes toward the police. Interview results provide evidence of a direct mechanism for increasing trust and cooperation with the police. Survey results indicate that positive contact with the police can shift general attitudes toward the police and reduce perceptions of police discrimination. Further, survey findings support the program as a remedial intervention for youth with previous negative police contact.
     (En)countering oppression: an argument for self-skepticism
    (En)countering oppression: an argument for self-skepticism
    Political philosophy has a lot to say about oppression, but does it adequately address the issue? This project asserts that it does not. The primary goal of this thesis is to redefine how we look at this socio-political problem, and to create a new model for analysis and application. I begin with a discussion of social contract theory and the many ways it has changed in an attempt to properly address the issue of oppression. Following this, the project turns towards an ethico-epistemological analysis of the elements of oppression in the modern social sphere. In this analysis, I look at prejudice, bias, disagreement, virtue, and vice as they pertain to the problem of oppression. Notably, this project considers the epistemic effects/affects of both the oppressed’s and the oppressor’s viewpoint. Finally, the project culminates in the development of the Argument for Self-Skepticism, my alternative to current social contract theory.
     A biomechanical study of a novel biomimetic hip implant.
    A biomechanical study of a novel biomimetic hip implant.
    A three dimensional finite element (FE) model of a novel carbon fibre polyamide 12 composite hip stem was used to compare with two commerically available (Exeter and Omnifit) hip stems to minimize stress shielding and bone resorption. A virtual axial load of 3000N was applied to the FE model which replicated the experimental study. Strain and stress distributions were computed and compared with experimental results. Experimentally, three hip stems had their distal portions rigidly mounted and had strain gauges placed along the surface at 3 medial and 3 lateral locations. From the FE analysis, the von mises stress range for the composite hip stem was 200% and 45% lower than that in the Omnifit and Exeter implants, respectively. The aggregate average difference between FE and experimental microstrains for four proximal strain gauge locations were 7.5% (composite), 11.5% (Exeter), 14.6% (Omnifit), and the composite hip stem's stiffness (1982N/mm) was lower than the metallic hip stem stiffnesses (Exter, 2460N/mm; Omnifit, 2543 N/mm). This study showed considerable improvement in stress transfer to bone tissue.
     A case study on most optimal power flow solutions to supply power to a new residential compound load located at
  the outskirts of an industrial area by using the optimization tools
    A case study on most optimal power flow solutions to supply power to a new residential compound load located at the outskirts of an industrial area by using the optimization tools
    This project studies different solutions, presents an efficient and reliable approach, to solve the optimal power flow (OPF) problem for an industrial power system by using fmincon optimization method and technique. This fmincon toolbox from MATLAB attempts to find a constrained minimum of a scalar function of several variables starting at an initial estimate. This is generally referred to as constrained nonlinear optimization or nonlinear programming. The objective in OPF problem is to minimize the total cost function of generating units and the transmission losses, while maintaining the design and performance of the entire power system, satisfying the operational requirements such as the real and reactive power outputs of the generating units, bus voltages and power flow of transmission lines…etc. This project presents the most optimal solution of power flow incorporating wind generation cost, to supply power to a new domestic load located at the outskirts of an industrial area for three different scenarios. This residential is typical of long rural line with isolated load area. The challenge in our case study is to incorporate a wind generation unit as one type of green energy, that are currently being considered as an alternative source of power, to feed this long rural line for the domestic load without effecting in the total generation cost. A case study is carried out for three different scenarios incorporating wind generation cost. The results of OPF in this project shows that incorporating wind generation unit as renewable energy source with the entire power system will have a minimum generation cost and minimum transmission losses for the entire power system even if the wind generation cost assumed to be the most expensive one comparing with other conventional generation units. This project report provides implementation of Algorithm for the entire power load flow using the fast decoupled power flow (FDPF) and optimizes the best solution for the three different scenarios by using fmincon Interior Point Algorithm as one of optimization toolbox to achieve the minimum total cost function of generating units and minimum transmission losses.
     A multi-objective optimization analysis of passive energy conservation measures in a Toronto house.
    A multi-objective optimization analysis of passive energy conservation measures in a Toronto house.
    This study presents a multi-objective optimization environment in which passive energy conservations measures of a high performance house in Toronto are evaluated. The optimization environment was created using the jEPlus software suite where the case study house acted as the reference building. The study house simulation model was calibrated using a data-driven procedure, and acceptable CV(RSME) and NMBE tolerances were reached in accordance with ASHRAE calibration requirements. The optimization varied passive energy efficiency parameters in search of configurations yielding optimal building performance and life cycle cost. The optimization results showed that energy savings of 33% relative to building code minimum were justified at the point of minimal life cycle cost via passive energy saving measures alone before considering active systems. These results suggest that improved thermal envelopes are economically advantageous with good building practice. However, they suggest that the current Passive House standard does not coincide with the economic minimum for the local economic and environmental climate.
     Analysis of the impacts of extreme weather events on Ontario’s electricity grid using agent-based modeling
    Analysis of the impacts of extreme weather events on Ontario’s electricity grid using agent-based modeling
    Extreme weather events have increased and are causing severe impacts on the electricity grid. Heat waves and ice storms are becoming more intense and frequent in Ontario, Canada. During an extreme weather event, the electricity demand fluctuates and the reliability of the electrical grid decreases due to equipment failure and shortage of electricity supply, which leads to blackouts. An initial stage simulation model is developed using the computational technique agent-based model. This thesis analyzed the impact of extreme weather events based on severity and frequency levels on two sector of Ontario’s electricity grid which are generation plants and distribution network. The simulation output showed multiple grid failures in different regions during extreme severity levels and increased frequencies of weather events. The model also showed heat waves and ice storms resulting differently depending on the month, extreme temperature months were more prone to failures than average temperature months.
     Between life and the underground : a study of photography found in Rolling Stone magazine from 1967 to 1972.
    Between life and the underground : a study of photography found in Rolling Stone magazine from 1967 to 1972.
    In order to consider what the photography used within Rolling Stone magazine contributes to the history of photojournalism, Between Life and the Underground analyzes the aesthetic of the photography and conceptual layouts produced within the magazine. This study looks specifically at the period of 1967 to 1972, a time when mainstream publications like Life magazine ceased production and when over 500 underground publications were piloted. A comparative analysis of the design, economics, and production of both Rolling Stone and the underground publication the Berkeley Barb traces the influence that the underground had on the aesthetic of Rolling Stone’s photography and layout. The role that cover photography played in perpetuating the identity that Rolling Stone wanted to embody is also investigated. The influence that New Journalism had on the production of photojournalism at Life and Rolling Stone is also considered—framed around a comparison of the photographic coverage of the Woodstock Festival of 1969 and the police riots at the Democratic National Convention of 1968. This study concludes that the underground press cultivated a new photographic aesthetic and conceptual technique for laying out photographs which adhered to the ideals of the 1960s—namely informality, which Rolling Stone then adapted to create a profitable magazine.
     Children's and parents' thoughts and feelings regarding nature in two types of locations:  comparisons and  implications
    Children's and parents' thoughts and feelings regarding nature in two types of locations: comparisons and implications
    This study examines the nature thoughts and feelings of 6 - 12 year-old children and their parents living in mountainous and city regions. It asks whether location and parental influences play roles in children's responses. Hypotheses assumed that participants in mountainous locations would be more connected with nature and that children's and parents' nature thoughts would correlate. Using mix-methods, surveys were distributed to 192 participants. Results illustrated that children in mountainous regions displayed more emotion words while children in the city displayed more descriptive words. No significant differences were found between parents. Compared to the urban sample, participants in mountainous regions felt that their environment was more a part of nature. Lastly, descriptive and total number of words correlated for parents and children. Recommendations include suggestions for curriculum design and childhood experiences. Parents, educators, and policy-makers should provide more unstructured outdoor play opportunities.
     Clinging to a knife’s edge: the Live-in Caregiver Program
    Clinging to a knife’s edge: the Live-in Caregiver Program
    Since the 1900s, Canada has heavily relied on foreign domestic workers. This program has evolved over the years into what is currently known as the Live-in Caregiver Program (LCP). It is rooted in our colonial history and has reproduced power imbalances between employers and caregivers. Challenging dominance is a difficult task given that immigration policies perpetuate inequalities through the denial of social, economic and political rights to caregivers. I selected this topic based on my experiences as a live-in caregiver with this program. This study uses anti-colonialism and feminist thought to examine the experiences of three former LCP workers. Through narrative interviewing, the findings indicate that the live-in requirement of the LCP has contributed to the abuse, exploitation and marginalization of these caregivers. The study concludes with a discussion of the ways in which the structure of the program can be modified to prevent further exploitation and human rights violations.