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.
      “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.
     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 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.
     An in vitro of radiation dose enhancement using gold nanorods and plasmonic photothermal therapy
    An in vitro of radiation dose enhancement using gold nanorods and plasmonic photothermal therapy
    Gold nanoparticles (GNP) have been shown to highly absorb ionizing radiation compared to tissue. GNPs have also been shown to be high absorbers of non-ionizing radiation with a peak absorbance at a wavelength dependent on their shape and size. This study investigated radiation dose enhancement in PC3 cells when in the presence of gold nanorods (NR) and near infrared light (IR). The PC3 cells were incubated with either PEGylated NRs (PNR) or anti prostate stem cell antigen antibody with nuclear localization sequence peptide conjugated NRs (AbNR). They were exposed to near infrared light at a wavelength of 810 nm to achieve a temperature of 42 ºC to 43 ºC for 60 minutes. They were also exposed to 160 kVp x-rays. It was found that both targeted and non-targeted GNPs when exposed to radiation and near infrared light synergistically enhanced radiation dose. It was also found that AbNRs provide greater dose enhancement than PNRs.
     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.
     Crashworthiness of vehicle-to-pole collisions using a hybrid III 3-year-old child dummy
    Crashworthiness of vehicle-to-pole collisions using a hybrid III 3-year-old child dummy
    To date, statistics indicate that motor vehicle crashes are one of the leading causes of death and injury for children despite improved crashworthiness of vehicles and child restraint systems, since children are at risk for devastating head and neck injuries due to their fragile physiology. Thus, this thesis focused on minimizing child injuries experienced during frontal vehicle-to-pole collisions by improving on the safety and energy absorption of existing traffic pole structures. A finite element computer model, using LS-DYNA software, was used to simulate crash events in order to determine the influence of pole structural and material characteristics on the injury parameters of a 3-year-old child dummy occupant. It was concluded that the anchored base support, and the embedded pole in soil systems provide desirable crashworthy results. In addition, it is recommended to mandate traffic protection devices in all areas with poor energy absorbing characteristics that resemble non-deformable objects.
     Data migration: relational RDBMS to non-relational NoSQL
    Data migration: relational RDBMS to non-relational NoSQL
    As a part of achieving specific targets, business decision making involves processing and analyzing large volumes of data that leads to growing enterprise databases day by day. Considering the size and complexity of the databases used in today’s enterprises, it is a major challenge for enterprises to re-engineering their applications that can handle large amounts of data. Compared to traditional relational databases, non-relational NoSQL databases are better suited for dynamic provisioning, horizontal scaling, significant performance, distributed architecture and developer agility benefits. Based on the concept of Object Relational Mapping (ORM) and traditional ETL data migration technique this thesis proposes a methodology for migrating data from RDBMS to NoSQL. The performance of the proposed solution is evaluated through a comparative analysis of RDBMS and NoSQL implementations based on query performance evaluation, query structure and developmental agility.
     Development of a web-based collaborative PPGIS to support municipal planning.
    Development of a web-based collaborative PPGIS to support municipal planning.
    The use of computing technologies to support workflows related to the planning and development of a municipality dates back to the late 1950s. The main boosts of computing technologies and applications, Geographic Information System (GIS) and Geographic Information Technology (GIT), in relation to a planning and decision-making context, became evident when the use of Public Participation GIS (PPGIS) started in the 1980s. Collaboration is an important part of many tasks involving people from different organizations, in which maps often play a central role in informing and improving debates and facilitating the decision-making process. It allows diverse stakeholders to share and view maps or spatial images interactively over the Web in real-time, among other platforms. The geospatial collaboration technology not only provides an effective solution to decision makers, but also facilitates scientific and public debates with real-time geospatial information. More recently, some efforts have been made using open map services to develop simple map-sharing applications. However, little has been done on designing and developing such online open source tools in the context of municipal planning and management. Further, a literature review indicates the lack of scientific publications on empirical studies of their practical applications. Web-based PPGIS applications, among others, have now been widely recognized as an efficient and integral part of sound planning and development processes to support public participation. However, GIS alone cannot make the planning process more participative. Demands for Web-based PPGIS tools, integrated with other information and computer-supported cooperative work (CSCW) tools, have rapidly become increasingly important for supporting collaborative participation during a decision-making process. Therefore, the establishment of public participation in GIS-based applications is an optimistic step taken by the researchers that are progressively working on municipal planning projects that incorporate public participation. The main aim of this research is to provide a Collaborative PPGIS (Co-PPGIS) to enhance public participation in municipal planning related workflows. A research prototype has been developed and its usability is evaluated by adopting the evaluation criteria for the research prototype, as only proper testing will demonstrate whether the prototype is usable or the Co-PPGIS design framework is successful in meeting end-users’ requirements.