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  • Novel Scalable Metasurface Control System

    Resource Type:
    Thesis
    Creator:
    Bascelli, David
    Abstract:
    A low cost controller was designed, simulated and tested in order to meet the requirements of bias control for active metasurfaces. The controller was required to set the bias elements on arbitrary metasurface designs containing both PIN Diodes and Varactors. This controller has a distributed architecture allowing it to be scaled to any metasurface required, while being easy to integrate into future metasurface designs. Programmatic control was achieved through a Python script in the same environment as test and measurement equipment, allowing for a fully automated experimentation setup. This controller was then applied to the beam steering of a metasurface, and control was demonstrated in real time. New applications are made possible by the low cost and ease of integration.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Electrical and Computer
    Date Created:
    2022

  • Spatial and temporal variation of microplastics in the Ottawa River watershed with citizen science as a complementary sampling methodology

    Resource Type:
    Thesis
    Creator:
    Forrest, Shaun
    Abstract:
    Microplastic concentrations were investigated in water and sediment in the Ottawa River watershed in Quebec and Ontario, Canada. Microplastic concentrations were measured temporally during precipitation events in an urban creek in the City of Ottawa and on the main channel of the Ottawa River within the Ottawa/Gatineau urban area. The temporal events sampled included heavy rainfall, snowfall and snow melt with microplastic concentrations measured from these events compared to concentrations during non-precipitation events. The results showed sewage overflows contribute to large short-term inputs of microplastics to the Ottawa River, however, spring snowmelt presented the highest increase of microplastic concentration for both the urban creek and main channel of the river. Additionally, the research examined the spatial distribution of microplastics in river water throughout the Ottawa River at 105 sample points on the main channel and tributaries. An ANCOVA analysis demonstrated only two significant spatial factors related to microplastic concentration, with distance downstream from the river source and an increase of microplastics at boat launch locations. However, these were both only weak relationships. The research incorporated two citizen science projects to investigate microplastic concentration in water and sediment in the Ottawa River watershed, while evaluating the potential of citizen science as a complementary sampling tool for microplastic research. With robust project design and implementation, citizen science is an excellent complementary tool for examining microplastic concentration in freshwater environments as it can reduce research costs, while increasing spatial scope of microplastic projects. Additionally, increasing citizen science capacity in microplastic research and monitoring is a useful tool to engage volunteers and involve them in environmental education while contributing to advancing the understanding of microplastic pollution.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Geography
    Date Created:
    2022

  • Three Essays on Macroeconomics with a Focus on Household Finance

    Resource Type:
    Thesis
    Creator:
    Xu, Jingjing
    Abstract:
    This thesis includes three essays on Macroeconomics with a focus on household finance. The essays aim to contribute to a deeper understanding of how individuals' and households' consumption, saving, and investment decisions are affected by external factors such as an economic shock or a policy change, and the mechanisms behind their responses.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Economics
    Date Created:
    2022

  • The Dark Side of Being Connected: Image-Based Sexual Exploitation, Dark Personality Traits, and Coercion Perceptions

    Resource Type:
    Thesis
    Creator:
    Swanek, Jessie Arynne
    Abstract:
    Technology use has brought about the perpetration of both sexting coercion and image-based sexual abuse. This study examined the association between the Dark Tetrad, propensity to morally disengage, and the perpetration of sexting coercion and image-based sexual abuse. This study also examined how those variables influence how someone perceives online coercion, when relationship type and coercion tactic are altered. With 1467 university students (72% women), higher psychopathy, sadism, or narcissism scores was associated with perpetrating image-based sexual abuse. For sexting coercion, identifying as a man, and higher narcissism scores were associated with perpetrating sexting coercion. Examining the vignettes, being a woman, not having perpetrated sexting coercion, and being higher in moral disengagement propensity altered perceptions of coercion; and a main effect for coercion tactic was found. This study showed that the general aggression model appears to be a valid theory to explain image-based sexual abuse and sexting coercion perpetration.
    Thesis Degree:
    Master of Arts (M.A.)
    Thesis Degree Discipline:
    Psychology
    Date Created:
    2022

  • “Microstructure Analysis of Polymer amended Fluid Fine Tailings Using Fiji-ImageJ Image analysis software”

    Resource Type:
    Thesis
    Creator:
    Sallam, Nadine Nasser Mostafa Saad
    Abstract:
    Optimizing the flocculation process is crucial for improving the long-term dewatering behaviour of oil sands tailings. The objective of this research is to assess the long-term dewatering behaviour of the polymer amended Fluid Fine Tailings (FFTs) from reliable key indicators at an early stage of the production process, specifically, using optical microscopy images. The experiments include processing optical microscope images using an image analysis software, "Fiji-Image J", to generate quantitative metrics of floc morphology. Particle size distributions derived from the Image J based analyses show replicability, when multiple images from the same sample are analyzed. Preliminary correlations between image metrics and consolidation characteristics show some explanatory power, though further advanced statistical analyses will be required to properly assess the predictive power of the image-derived information.
    Thesis Degree:
    Master of Applied Science (M.App.Sc.)
    Thesis Degree Discipline:
    Engineering, Civil
    Date Created:
    2022

  • Visualizing Meaning : Managing Perception and Meaning in Visual Communication Design

    Resource Type:
    Thesis
    Creator:
    Craib, David
    Abstract:
    Visual communication designers strive to create effective visual messages that are easily perceived and meaningful, but various forms of visual noise can compromise their designs. A set of visual design criteria and tools, aimed to increase design efficiency and effectiveness will be developed through a literature review of communication-related disciplines, including psychology, linguistics, semiotics, communications studies, information theory and statistics design. A sampling of these criteria and tools will then be applied to case studies of web- and print-based visual presentations to research their viability, and expert interviews will further inform and develop the criteria list. The final criteria and tools, developed from the studies, will be used to build a prototype of a corporate at a glance presentation for a government organization, to research the usability of the criteria set. The research aims to develop visual communication design theory based on fundamental, interdisciplinary concepts that could, through further research, offer visual communication designers improved science-based design and research tools.
    Thesis Degree:
    Master of Design (M.Des.)
    Thesis Degree Discipline:
    Industrial Design
    Date Created:
    2013

  • Preserving Safety, Dignity and Autonomy Through Multi-Modal Interactions: An Exploration into a Preferred Future of Design for Accessible Dressing Technology and E-Textiles

    Resource Type:
    Thesis
    Creator:
    Moore, Sarah Jane
    Abstract:
    Ready-to-wear clothing is often designed for individuals without disabilities, which can create dressing barriers and challenges for individuals with disabilities, especially those with motor coordination, cognitive challenges sensory and self-regulation issues. In two studies we explored the visions of occupational therapists for the future of dressing through smart clothing and dressing technology. Using co-design and design fiction online workshops, we were able to gather a rich data set that included interview data, virtual sticky notes, creative writing exercises and storyboards. We coded and used thematic and abductive analysis to explore the data and created design fictions to explore the future of dressing technology. Occupational therapists identified challenges that impact dressing tasks, and requirements for the design of technology situated in the near future that would support the autonomy of disabled people.
    Thesis Degree:
    Master of Arts (M.A.)
    Thesis Degree Discipline:
    Human-Computer Interaction
    Date Created:
    2022

  • The Dialectic of Logos and Eros: Plato’s Display of Rhetoric in the Phaedrus and the Symposium

    Resource Type:
    Thesis
    Creator:
    Gao, Yipin
    Abstract:
    This dissertation offers an interpretation of Plato's philosophical writing that relies on the discussion of speech that is displayed in the Phaedrus. As Socrates shows in this discussion of speech, the philosophical writer who wishes to teach the philosopher's art of thinking must write in a way that could facilitate the serious activity of philosophy or dialectic, that is, the examination of the powers and affects of things that are said to be beneficial or harmful to human beings. In both the Phaedrus and the Symposium, Plato displays various speeches of praise and blame about erōs or love to which Socrates must respond, hence inviting his audience to examine for themselves the natures of speech and love as complex things, both in terms of their powers and affects in relation to the human soul. In other words, rather than the indoctrination of some rigid metaphysical system, Plato sought to teach through his philosophical writing-dramatic works which can be identified as Plato's "display of rhetoric"-an arduous art of thinking that Socrates calls dialectic.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Political Science
    Date Created:
    2022

  • Approximate Methods For Analyzing Semi-Parametric Longitudinal Models With Non-Ignorable Missing Responses

    Resource Type:
    Thesis
    Creator:
    Aloraini, Najla Mohammed
    Abstract:
    In this thesis, we suggest and explore semi-parametric generalized partially linear mixed models for longitudinal data with non-ignorable and non-monotone missing responses. The key subject of our attention is the estimation of mean response parameters and variance components using a semi-parametric Monte Carlo EM method, where the conditional mean response is semi-parametric. We first discuss the penalized regression spline method, which is often referred to as P-splines, for linear mixed model. We investigate the connection between P-splines and linear mixed model through incorporating the non-parametric mean functions into longitudinal linear mixed model. An extensive simulation study using different semi-parametric mean response functions are presented. Our simulation study reports that when the true underlying model is partially linear, the penalized spline method provides unbiased and efficient estimators. On the other hand, when the mean response is a correctly specified linear model, the P-spline still provides reliable estimates of the model parameters. Next, we present semi-parametric generalized partially linear mixed models for longitudinal data with non-ignorable missing responses. In this situation, we introduce a parametric model for non-ignorable missing data and incorporate it into the likelihood function. We obtain the asymptotic variances of the proposed estimators by the method of Louis (cf. [2], [7]). In addition, we propose and explore a semi-parametric Monte Carlo EM (MCEM) algorithm for simultaneous estimation of the regression parameters and variance components in partially linear mixed models with non-ignorable and non-monotone missing responses. In simulations, the empirical properties of the proposed method are evaluated. The simulation study shows that our proposed semi-parametric method performs well even under a large proportion of non-ignorable missing responses. Finally, the proposed semi-parametric MCEM method are applied to some actual longitudinal data obtained from a health survey, referred to as the Health and Retirement Study (HRS). The data showed strong evidence of a non-linear trend in the mean response function. It is evident from this application that our proposed methods can be used to improve the efficiency of the estimates in a partially linear mixed model for longitudinal data with non-ignorable missing responses.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Probability and Statistics
    Date Created:
    2022

  • Selective Detection and Removal of Zinc Oxide Nanoparticles in Contaminated Water

    Resource Type:
    Thesis
    Creator:
    Zhang, Wenyu
    Abstract:
    Metal oxide nanoparticles (MONPs) are massively produced for various industrial, environmental and biomedical applications due to their high surface reactivity and unique chemical and physical properties. Among all the manufactured MONPs, human exposure to zinc oxide (ZnO) nanoparticles may cause significant health concerns. This leads to a desire for efficient methods for their facile detection in the aqueous environment. In this work, two detection methods and one removal method were developed to selectively detect or remove ZnO nanoparticles in contaminated water with the presence of other MONPs. A detection method based on the fluorescence quenching of meso-tetra(4-carboxyphenyl) porphyrin (TCPP) has been developed to treat water samples containing MONPs. Quenching of the TCPP emission intensity at 650 nm provides a Stern-Volmer plot with adequate sensitivity for the detection of 0.15 mg/mL ZnO nanoparticles. Meanwhile, a unique emission peak at 605 nm is observed and can be used for the identification and quantitation of ZnO nanoparticles down to 0.0015 mg/mL. A removal method using 3-aminopropyltriethoxysilane (APTES) has been proved to sediment ZnO nanoparticles in aqueous suspension with TCPP as a color indicator for ZnO. When 2.0% (v) APTES is applied to treat water samples containing ≥ 0.5 mg/mL of ZnO nanoparticles, a web-like sediment adheres onto the glass vial bottom from APTES-ZnO conjugation. A high removal efficiency of over 99% (w) ZnO nanoparticles was attained using APTES. Another detection method has been developed using electroanalytical analysis by firstly drop-casting MONPs on a screen-printed electrode. When phenol is analyzed as a chemical probe by cyclic voltammetry (CV), measurement of the reduction current provides adequate sensitivity for the indirect quantitation of 0.1 mg/mL ZnO nanoparticles. Both the oxidation peak and charge storage capacity measured from the cyclic voltammogram are proportional to the ZnO nanoparticle concentration and can afford a better detection limit of 0.01 mg/mL. Overall, the above methods are labour and cost effective and can afford high selectivity towards ZnO detection or removal in the presence of other MONPs. Additionally, the electrochemical analysis method and the APTES sedimentation method can differentiate ZnO nanoparticles from Zn2+ and zinc peroxide (ZnO2) nanoparticles.
    Thesis Degree:
    Doctor of Philosophy (Ph.D.)
    Thesis Degree Discipline:
    Chemistry
    Date Created:
    2022