Theses

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  • Toxicity and bioaccumulation of 2,2', 4,4'-tetrabromodiphenyl ether (BDE47) in a laboratory aquatic food chain
    Toxicity and bioaccumulation of 2,2', 4,4'-tetrabromodiphenyl ether (BDE47) in a laboratory aquatic food chain
    Rising levels of polybrominated diphenyl ethers (PBDEs) have been ovserved in the environment, humans, and animlas. Studies have shown that these compounds can elicit toxic effects in animals (e.g. neurotoxicity and thyroid toxicity). This research investigated the effects of BDE47 on the survival and reproduction of Daphnia magna over two generations. The impacts of water-borne exposure were compared to dietary exposure using the following treatments: dosed water (DW), dosed algae (DA) and dosed water and algae (DWA). In the first generation, significant impacts on reproduction were observed in daphnids in the DA and DWA treatments. In the second generation, no significant impacts on reproduction were observed indicating a recovery from maternal exposure. When second generation daphnids were exposed to BDE47, there was high mortality in the DWA treatment anad reduced reproduction in all dosed treatments. Dietary exposure to BDE47 had a more profound impact on daphnid reproduction than water exposure. In the second generation, dietary exposure affected both survival and reproduction and water exposure reduced reproduction, indicating that maternal exposure was a factor.
    Tracking Human Motion in Monocular Video Sequence with the De-Mc Particle Filter
    Tracking Human Motion in Monocular Video Sequence with the De-Mc Particle Filter
    Tracking human motion from monocular video sequences has attracted a great deal of interests in recent years. The difficulty in solving this problem is largely due to the nonlinear property of human dynamics and the high dimensionality of the state vector space required to model human motion. Traditional particle filtering methods usually fail in this situation because the distributions they sample from are ill-defined. In this thesis we propose a novel tracking algorithm, namely the Differential Evolution - Markov Chain (DE-MC) particle filtering. It is based on the particle filter framework but makes substantial changes to its core, i.e. the sampling strategy. In this new approach, the Differential Evolution algorithm and the Markov Chain Monte Carlo algorithm are integrated, aiming at improving both the accuracy and efficiency in approximating the posterior distribution. Global optimization and importance sampling are spirits of the proposed method. To apply the DE-MC particle filter to articulated model-based human motion tracking, we also integrate multiple image cues including the area of silhouettes, color histograms and boundaries to measure the image likelihoods. We find the Fourier Descriptor (FD) to be a new and effective image feature in human motion tracking applications. Our other contributions, such as a modified color cue-based measurement function and a simple adaptive strategy for sampling, also help to improve the performance of the human tracker. Experimental results including the comparison with the performance of other particle filtering methods demonstrate the power of the proposed approach.
    Traditional medicinal knowledge, recognition and regulation
    Traditional medicinal knowledge, recognition and regulation
    As a number of global legal and political institutions grapple with ways to recognize and integrate TMK into their institutional frameworks, how traditional practices are 'recognized', and what work 'recognition's being asked to do become key questions. Three international frameworks that play a key role in recognizing TMK in the international arena are the Convention on Biological Diversity, the World Intellectual Property Organization and the World Health Organization. By examining the way in which these three bodies have recognized and integrated TMK into their respective regimes, while and drawing on the scholarship of anthropologists, critical legal scholars, intellectual property experts and legal and policy literature, I will argue that the recognition of TMK in the international legal and political arena has led to the creation of complex legal and political spaces where recognizing traditional medicinal knowledge has fragmented it, siphoning off the social, cultural and spiritual aspects of it that remain incompatible with the current neoliberal paradigms. Simultaneously, recognition and integration have been used to co-opt traditional knowledge in order to extend governance regimes that integrate TMK and its holders without challenging the basic, outdated and highly unequal and unethical power relations on discourses of recognition are based.
    Traffic engineering friendly request routing in content delivery network
    Traffic engineering friendly request routing in content delivery network
    Content delivery over Internet is optimized for low use perceived latency by designing specialized Content Distribution Network (CDN). Content servers are connected through a content switch the distributes client requests among them to achieve load balancing across the servers. The content switch is located one-hop away from the servers. Server load balancing is one factor in achieveing low user perceived latency and improving operational efficiency. Traffic engineering is another factor that is generally and integrated with serverload balancing for CDN optimization. In this thesis we propose a request routing algorithm for a CDN that was designed to integrate server selection and traffic engineering functions in the request routing system. The CDN employs MPLS in the network for traffic engineering. The proposed algorithm optimizes content delivery for user perceived latency by achieving server load balancing and network traffic loan manaement among alternative paths. It also improves operational efficiency of the CDN by eliminating bottleneck paths and increasing utilization of underutilized servers and paths.
    Traffic signal coordination for Wellington Street West, Toronto, Ontario
    Traffic signal coordination for Wellington Street West, Toronto, Ontario
    The increasing volume of traffic in cities has a significant effect on road traffic congestion and the travel time it takes for road users to reach their destinations. Coordinating traffic signals, which is a system of light that cascade in sequence where a platoon of vehicles can travel through a continuous series of green light without stopping, can improve the driver's experience significantly. This report covers the development of a coordinated traffic signal system along Wellington Street West from Church Street to Blue Jays Way Street as part of a City of Toronto signal coordination project. The objective of this study is to improve coordination through modification of signal timing plans while maintaining reasonably minimal impacts to the side street levels of service and delays. The overall goal is to reduced travel times, delays, number of stops and fuel consumption, resulting in public benefit.
    Trajectory Analysis on Spherical Self-Organizing Maps With Application to Gesture Recognition
    Trajectory Analysis on Spherical Self-Organizing Maps With Application to Gesture Recognition
    In this work, a new approach to gesture recognition using the properties of Spherical Self- Organizing Map (SSOM) is investigated. Bounded mapping of data onto a SSOM creates not only a powerful tool for visualization but also for modeling spatiotemporal information of gesture data. The SSOM allows for the automated decomposition of a variety of gestures into a set of distinct postures. The decomposition naturally organizes this set into a spatial map that preserves associations between postures, upon which we formalize the notion of a gesture as a trajectory through learned posture space. Trajectories from different gestures may share postures. However, the path traversed through posture space is relatively unique. Different variations of posture transitions occurring within a gesture trajectory are used to classify new unknown gestures. Four mechanisms for detecting the occurrence of a trajectory of an unknown gesture are proposed and evaluated on two data sets involving both hand gestures (public sign language database) and full body gestures (Microsoft Kinect database collected in-house) showing the effectiveness of the proposed approach.
    Trajectory based market models with operational assumptions
    Trajectory based market models with operational assumptions
    Mathematical finance makes use of stochastic processes to model sources of uncertainty in market prices. Such models have helped in the assessment of many financial situations. These approaches impose the stochastic process a priori which is then fitted to data. Hence, unchecked hypotheses can creep into the formalism and observable phenomena plays little role in building the model fundamentals. We attempt to reverse the procedure in order to include presumably more realistic price movements. Operational assumptions are used to construct a trajectory set relating discrete chart properties with investors' portfolio re-balancing preferences. By identifying features of these trajectories we can construct models that capture different sources of risk and use a geometric procedure to produce replication bounds for a contingent claim. Why a future unfolding chart fails to belong to the proposed trajectory set is testable. A preliminary risk-reward analysis based on this is also developed.
    Trans Forming Education: An examination of the ways in which Teachers' construct gender and understand gender independence in TDSB elementary school classrooms
    Trans Forming Education: An examination of the ways in which Teachers' construct gender and understand gender independence in TDSB elementary school classrooms
    This study focuses on the ways in which teachers construct and understand gender and gender independence in children. This study also explores the ways in which teachers strive to accommodate and include children who are gender independent. Six elementary school teachers who were positive space representatives or who self-identified as Lesbian, Gay, Bisexual, Transgendered or Queer (LGBTQ) advocates in their schools were interviewed regarding the ways in which they constructed and understood gender identity and gender independence in their classrooms. The teachers, who taught between kindergarten and grade eight, were questioned about their familiarity with the Toronto District School Board (TDSB) guideline for the accommodation of transgender and gender non-conforming students and staff. Teachers' experiences with children who were gender independent were also examined. Interviews focused on examining the ways that teachers constructed gender in their classrooms. Teachers were asked to identify barriers to inclusion, as well as the resources and supports available regarding the inclusion of gender independent children. Teachers were also asked to identify any additional resources they felt would be beneficial towards facilitating the inclusion of children who were gender independent. A combination of theoretical lenses consisting of disability theory, queer theory and feminist theory has been used throughout this study. Themes found include: Gender as constructed, Gender as performed, teachers' roles in reinforcing or shaping gender performance, constructing male and female gender independence, and creating inclusive environments. The implications of these results include suggestions for creating classrooms and schools that are inclusive to children who may be gender independent.
    Transfer of the Catabolic Plasmid Pjp4 in Bacterial Biofilms in Lab-Scale Continuous Flow-Through Cells
    Transfer of the Catabolic Plasmid Pjp4 in Bacterial Biofilms in Lab-Scale Continuous Flow-Through Cells
    Limited information is available on how external environmental factors (e.g., the type of carbon source) affect biofilm architecture, conjugative transfer of the plasmid pJP4 and xenobiotic degradation in biofilms. The aim of this project was to investigate the influence of glucose and 2,4-dichlorophenoxyacetic acid, two different carbon sources which represent the absence and presence of selective pressure, respectively, on the combined effect of biofilm architecture, transfer of the plasmid pJP4 in soil derived mixed culture biofilms and consequent biodegradation of 2,4-D. The pJP4 plasmid was transferred to soil-derived mixed culture recipients in plate mating experiments and isolated transconjugant colonies were characterized as Comamonas testosteroni. Donor and transconjugant cells were not detected microscopically in biofilms and no transconjugant colonies were isolated; however, gfp, dsRed, and tfdB genes were detected in biofilm effluents with and without selective pressure. Heterogeneous biofilm architecture was observed for both with and without selective pressure.
    Transformation as a type: seeking a flexible housing type for the 21st century
    Transformation as a type: seeking a flexible housing type for the 21st century
    Rapid social and technological change have largely influenced the way in which individuals and families inhabit their dwellings, leading to new functional and formal lifestyle demands within the domestic realm. “The current information society is more closely linked to time than space. Its networks produce systems that are discontinuous in space but continuous in time…the most consistent systems are those capable of distributing their activities homogeneously in time, thus avoiding the generation of another parallel space…specifically for one concrete use.” (Guallart, 2004, p.25) In a time where change and transformation are omnipresent and highly influential, how can we design habitats that respond directly to the changing social order, by transforming into the appropriate space which supports the changing occupants, activities, and functions of a home? This thesis proposes a flexible housing typology, which has the ability to transform and adapt to socio-cultural and technological changes over time.
    Transgressive actions and the production of public space : policy, people and urban space in Winnipeg's downtown
    Transgressive actions and the production of public space : policy, people and urban space in Winnipeg's downtown
    Public space is planned space. The discourse that takes place among federal, municipal and local governments, as well as the interaction that takes place on the street between people, informs the agenda and values inherent in policy and social norms. Urban revitalization strategies and city bylaws produce public and private spaces, thereby informing the cityscape within which everyone interacts. This study examines the contribution, circulation and regulation of transgressive actions in Winnipeg, Manitoba, Canada, in order to consider what these actions reveal about power relations in the urban environment and the production of public space. This research uses both a policy case study and urban theory to investigate the means by which public and private spaces are produced and imbued with the ideologies that shape and maintain these spaces in Winnipeg's downtown area.
    Transit-Oriented Development: Removing Barriers And Realizing Goals Through LEED-ND
    Transit-Oriented Development: Removing Barriers And Realizing Goals Through LEED-ND
    In a response to the effects of sprawl and the growth pressures that face the City of Toronto and the rest of the Province of Ontario, Transit-Oriented Development (TOD) can be implemented as a smart growth tool that can provide a meaningful sustainable alternative to conventional development practices. This research paper explores TOD in all of its capacities, context, design principles and the benefits and barriers that encourage or inhibit its execution. With a lack of effective performance measures in the current literature, this report aims to respond to the question: Can LEED-ND assist in addressing the main goals, objectives and barriers of TOD? LEED-ND is a rating system that shares the same smartgrowth and new urbanist concepts as TOD. The various categories of the LEED-ND system help to analyze TODs by more than just design elements and instead help to put focus on the sustainable and social objectives.