Theses

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  • A Channel Based Fair Scheduling Scheme For Downlink High Speed Data In CDMA Networks
    A Channel Based Fair Scheduling Scheme For Downlink High Speed Data In CDMA Networks
    High speed data transmission in wireless networks demands better radio resource management schemes. The research work for this thesis considers packet scheduling in downlinks of a cellular CDMA system for delay-tolerant applications. In this thesis, a packet scheduling scheme is proposed that attempts to provide fair allocation of individuals throughout and obtain relatively high system throughput. It is based on combined consideration of channel conditions, required throughput and achieved average throughput. A priority factor and system tolerance factor are introduced. We confirmed the trade-off between system throughout (i.e., efficiency) and individual throughput (i.e., fairness) by both analysis and simulation. Relative performance between the proposed scheme and traditional schemes is evaluated through simulation to confirm the analytical observations. The sensitivity of system tolerance factor towards efficiency and fairness was also investigated. Overall, the proposed scheme performs between absolute unfairness scheme and absolute fairness scheme in term s of system throughput and fair allocation of individual throughput.
    A City In The Sky: Engaging The Vertical Public Realm
    A City In The Sky: Engaging The Vertical Public Realm
    Urban public spaces are synonymous with the social fabric of the city, forming overlapping networks of face-to-face interaction. As population growth in Toronto intensifies, the city is experiencing an increase in developer-driven, private high-rise residential buildings and subsequent loss of public space for social interaction. Face-to-face interaction is vital to human health and well-being as it satisfies the need for self-identity and relationships at the scale of the individual and the community. Architectural design provides the means to explore possibilities for alternative social spaces in contemporary cities through the design of a vertical public realm within high-rise residential towers. The socio-spatial organization and disposition of public and private space can foster social interaction across a variety of scales. This is vital in forming communities within a high-rise residential tower that will grow together over time, creating a cohesive urban system at the scale of the neighbourhood, community and city
    A Cluster-Based Browsing Model For QoS-Aware Web Service Selection
    A Cluster-Based Browsing Model For QoS-Aware Web Service Selection
    In the last decade, selecting suitable web services based on users’ requirements has become one of the major subjects in the web service domain. Any research works have been done - either based on functional requirements, or focusing more on Quality of Service (QoS) - based selection. We believe that searching is not the only way to implement the selection. Selection could also be done by browsing, or by a combination of searching and browsing. In this thesis, we propose a browsing method based on the Scatter/Gather model, which helps users gain a better understanding of the QoS value distribution of the web services and locate their desired services. Because the Scatter/Gather model uses cluster analysis techniques and web service QoS data is best represented as a vector of intervals, or more generically a vector of symbolic data, we apply for symbolic clustering algorithm and implement different variations of the Scatter/Gather model. Through our experiments on both synthetic and real datasets, we identify the most efficient ( based on the processing time) and effective implementations.
    A Comparative Analysis Of MEMS Parallel Plate Actuators
    A Comparative Analysis Of MEMS Parallel Plate Actuators
    The purpose of this study is to compare the deformation of the moving top plate of five distinct parallel plate capacitor designs under applied voltage as well as compare the pull-in voltage of each design. The parallel plate designs are created using AutoCAD 2008 software and the simulations are performed using CoventorWare 2010. The control design is first validated with known results and then compared to the remaining four designs. Finally, pull-in voltages of all five designs is determined and compared to determine the advantages and disadvantages of each design.
    A Comparative Investigation In Measuring Food Access: Food Deserts In Urban Setting
    A Comparative Investigation In Measuring Food Access: Food Deserts In Urban Setting
    An increasing number of food desert studies over the past two decades have attempted to identify urban areas with inadequate access to nutritious and affordable food with implications for public health social equity and environmental issues. Due to different ways of operationalizing food desert analysis and the multifaceted dimension of the concept, there are inherent ambiguities in the validity and accuracy of food desert results across different studies. This study challenged the conventional measurements of food availability (e.g., distance-to-supermarket criterion) and food accessibility (e.g., circular buffer method) in identifying food deserts. An alternative methodology was developed that considered a wider variety of healthy food sources and used a network buffer method to produce more comprehensive results. Using Geographic Information System (GIS) analysis, alternative measures of food deserts were tested empirically in one Toronto ‘disadvantaged’ neighborhood. The results indicated that different areas were identified as part of a food desert depending on the methodology used. It concludes that failing to use a broader set of food desert elements can significantly alter the results in the study area.
    A Comparative Study of Formation Control at the Earth-Moon L₂ Libration Point
    A Comparative Study of Formation Control at the Earth-Moon L₂ Libration Point
    This thesis examines the performance of control methods that fall under the optimal, predictive and adaptive classifications, subjected to sensor/actuator faults, and presents approaches to apply them to non-affine systems utilizing single thruster and solar sail actuator configurations. The system of interest consists of a leader-follower satellite formation near the L2 point of the Earth-Moon system. The control methods studied here include those which are emerging in the space systems literature, and are evaluated in terms of their transient and steady state responses, and control input variation. Numerical simulation of faults affecting both sensor and propulsion actuator systems are conducted, along with an experiment to validate the results in a laboratory environment. The observed behavioral characteristics in the simulations match those demonstrated in the experiment. Alternative representations of dynamics were explored for controller design of non-affine systems. The research presented herein provides support for the usage of the proposed control strategies in future space applications.
    A Comparative Study of the Impact of Data Augmentation in Machine Learning Based Classification Accuracy
    A Comparative Study of the Impact of Data Augmentation in Machine Learning Based Classification Accuracy
    Traumatic Brain Injury is the primary cause of death and disability all over the world. Monitoring the intracranial pressure (ICP) and classifying it for hypertension signals is of crucial importance. This thesis explores the possibility of a better classification of the ICP signal and detection of hypertensive signal prior to the actual occurrence of the hypertensive episodes. This study differ from other approaches astime series is converted into images by Gramian angular field and Markov transition matrix and augmented with data. Due to unbalanced data, the effect of smote extended nearest neighbour algorithm for balancing the data is examined. We use various machine learning algorithms to classify the ICP signals. The results obtained shoe that Ada boost performance is the best among compared algorithms. F1 score of the Ada boost is 0.95 on original dataset, and 0.9967 on balanced and augmented dataset. Quadratic Discriminant Analysis F1 score is 1 when data is augmented and balanced.
    A Comparison Of Building Envelope Performance Levels Between Ontario, Denmark, Germany And The Passive House Standard, In The Low-Rise, Residential Context
    A Comparison Of Building Envelope Performance Levels Between Ontario, Denmark, Germany And The Passive House Standard, In The Low-Rise, Residential Context
    This research compared and analyzed where the Ontario Building Code rates in the low-rise, residential sector in terms of its: Current and past building envelope regulation requirements,‘Typical’ building envelope connection details,Current building envelopes regulation requirements in energy consumption and‘Typical’ building envelopes energy consumptionin comparison to Denmark, Germany and the Passive House Standard. This was analyzed to see how Ontario compared against other world renowned energy efficient regulations and where or if there was room for improvement. For this, HOT2000 and THERM were utilized on all four of the reference standards, where both of these programs were managed in a way to compare the results of ‘typical’ building envelopes and the current regulation from each of the standards. These results were then able to provide a whole home’s heating and air conditioning energy use in the Greater Toronto Area climate. Overall, the results illustrated Ontario homes consume the most energy for both typically constructed homes and homes utilizing the minimum requirements. In addition to this, Ontario also had the least performing building envelope connection details. In total, the Passive House performed at the highest level followed by Germany, Denmark and then Ontario.
    A Comparison of Acute Toxicity of Biodiesel, Biodiesel Blends and Diesel on Aquatic Organisms
    A Comparison of Acute Toxicity of Biodiesel, Biodiesel Blends and Diesel on Aquatic Organisms
    The increasing demand of alternative energy sources has created interest in biodiesel and biodiesel blends; biodiesel is promoted as a diesel substitute. Like diesel spills, biodiesel spills can have deleterious effects on aquatic environments. The effect of neat biodiesel, biodiesel blends and diesel on O. mykiss and D. magna was evaluated using acute toxicity testing. Static non-renewable bioassays of freshwater organisms containing B100, B50, B20, B5 and conventional diesel fuel were used to compare the acute effects of biodiesel to diesel. Mortality was the significant endpoint measurement in this study; percent mortality and lethal concentration (LC50) at different exposure times were determined from the acute toxicity tests performed. Trials were considered valid if the controls exhibited more than 90% survival. Based on percent mortality and LC50 values, a toxicity ranking of fuels was developed. The results of the definitive tests indicated that diesel is more toxic than neat biodiesel or biodiesel blends. This approach can provide insights into the lethality of biodiesel spills in the aquatic environment.
    A Comparison of Life Cycle Energy and Carbon Impacts for Passive Detached Accessory Dwelling Units and Their Design Implications
    A Comparison of Life Cycle Energy and Carbon Impacts for Passive Detached Accessory Dwelling Units and Their Design Implications
    Detached accessory dwelling units are a building typology that, when built to passive design standards, can help reduce GHG emissions while addressing the socioeconomic pressures facing many housing markets. Energy performance metrics like those used in passive design standards are based on per unit of floor area and lead to a size-bias against smaller housing typologies. A life cycle assessment of cost-optimal passive house sizes ranging from 230 m² (2,500 ft²) to 30 m² (300 ft²) is performed to understand their total life cycle energy use and GHG emissions implications. Additionally, an analysis using BEopt examines operational energy use for 10 cost-optimal passive house sizes ranging from 230 m² (2,500 ft²) to 30 m² (300 ft²) across all 17 climate zones and examines how cost-optimal passive design changes with house size. The results show that per-occupant energy use and GHG emissions are similar or better for small house sizes and that cost-optimal passive design does not change significantly with house size.
    A Complex-Lamellar Description Of Boundary Layer Transition
    A Complex-Lamellar Description Of Boundary Layer Transition
    Flow transition is important, in both practical and phenomenological terms. However, there is currently no method for identifying the spatial locations associated with transition, such as the start and end of intermittency. The concept of flow stability and experimental correlations have been used, however, flow stability only identifies the location where disturbances begin to grow in the laminar flow and experimental correlations can only give approximations as measuring the start and end of intermittency is diffcult. Therefore, the focus of this work is to construct a method to identify the start and end of intermittency, for a natural boundary layer transition and a separated flow transition. We obtain these locations by deriving a complex-lamellar description of the velocity field that exists between a fully laminar and fully turbulent boundary condition. Mathematically, this complex-lamellar decomposition, which is constructed from the classical Darwin-Lighthill-Hawthorne drift function and the transport of enstrophy, describes the flow that exists between the fully laminar Pohlhausen equations and Prandtl's fully turbulent one seventh power law. We approximate the difference in enstrophy density between the boundary conditions using a power series. The slope of the power series is scaled by using the shape of the universal intermittency distribution within the intermittency region. We solve the complex-lamellar decomposition of the velocity field along with the slope of the difference in enstrophy density function to determine the location of the laminar and turbulent boundary conditions. Then from the difference in enstrophy density function we calculate the start and end of intermittency. We perform this calculation on a natural boundary layer transition over a flat plate for zero pressure gradient flow and for separated shear flow over a separation bubble. We compare these results to existing experimental results and verify the accuracy of our transition model.
    A Comprehensive Planning Framework for Urban Inland Oil Spill Management
    A Comprehensive Planning Framework for Urban Inland Oil Spill Management
    Oil spills occurring on land have accounted for at least one third or over 24,000 of all land spills (approximately 76,000) of various substances reported in Ontario from 1988 to 2013. The objective of this research was to develop a comprehensive planning framework for urban inland oil spill management encompassing all three stages of spill management: (1) prevention, (2) control and (3) response. An inland oil spill database was developed and the source of each spill was analyzed. Preliminary analyses determined that approximately 46 % of spills occur at fixed locations (stationary spills), 21 % of spills involve moving vehicles (transportation-related), 13 % involve moving vehicle accidents (transportation-related accidents) and 20 % were categorized as other kinds of spills. Sub-databases were developed for both stationary and transportation-related spills which include numeric and non-numeric data variables. Hot spot analyses (optimized version) were performed on a subset of transportation-related spills to develop a highway spill model. The highway spill model illustrates that the majority of highway spills (75 %) occur at interchanges and the remaining spills occur either on the highway (8 %) or at unknown locations (17%). A macro program was developed to simulate future spill events based on historical spill events of gasoline spills within the case study area. The variables under study were fitted with distributions and Monte Carlo or Iman Conover methods were used to generate simulation results spreadsheets of spill series data based on the fitted distributions. The final macro program generated 30,000 simulation results spreadsheets and compiled the results in an aggregate spreadsheet. Descriptive statistics of the numeric variables were calculated and used to recommend spill management strategies. A simulation results spreadsheet with predicted spill records was used to develop a Geographic Information Systems (GIS) model to delineate spill pathways and calculate travel-time for overland flow and channel flow within the storm sewer system (geometric network). The model delineates the overland spill path and traces the spill path through the storm sewer network. The travel-time for each type of path is calculated and can be summed to determine the total travel-time for each predicted spill. Keywords: inland oil spill, comprehensive planning framework, spill management, prevention, control, response, stationary, transportation-related, hot spot analysis, macro program, Monte Carlo, Iman Conover, simulation, GIS, travel-time, spill path, geometric network