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Consent of the Governed and Other Fables
No full textThe consent of the governed plays a pivotal role in liberal philosophy. From Hobbes, Locke, and Rousseau, through to Kant and modern theorists such as John Rawls and Jeremy Waldron, consent has been the primary means by which the authority of the state gains legitimacy. We rarely think authoritative institutions need the actual consent of all those over whom they rule. Agents of the state cannot go around asking each individual person if they consent to each individual law, for example. For pragmatic reasons, the focus is on hypothetical consent – that is to say, if a reasonable person would consent to an authoritative institution, that institution is legitimate without needing to attain actual, direct consent.
However, what you imagine a reasonable person would hypothetically consent to rests on what you believe about a variety of empirical facts about human history and human psychology, i.e. on what you believe about “human nature”. In this thesis I argue that most political philosophers do not seem particularly well-informed about these topics, often forming beliefs based on an outdated and/or false understanding of what human beings are like, or have historically been like, laying an epistemically unreliable foundation for political beliefs and leading liberal philosophers to regularly misunderstand the implications of the principles they advocate for. I further argue that there are good reasons to think that the kind of society which best instantiates liberal principles looks very different than what most people imagine
Gaze-Enabled Grasping Assistance For Teleoperation of Robotic Manipulators
No full textShared autonomy in robot teleoperation can ease task completion and lower cognitive load for operators by combining human intent with the autonomous capabilities of robots. As many manipulation control tasks involve the grasping of objects as the first step, augmenting assistance at this stage has the potential to improve user experience and task performance. Existing grasping assistance systems rely on classic grasp planners that limit their capabilities, while some utilize expensive hardware to provide the assistance. Virtual reality systems have been used for input and feedback in teleoperation and have also been applied in grasping assistance systems. Some virtual reality systems feature head-mounted displays that have eye-tracking capabilities, and research has been conducted to leverage the eye-tracking information for teleoperation applications.
This work introduces a novel grasping assistance framework that leverages user intent signalled through eye gaze. Specifically, the system retrieves eye gaze direction from a virtual reality headset during teleoperation. This gaze information is then used to automatically identify the operator's desired object for grasping, suggest suitable grasp options, and allow the operator to select a preferred grasp using their gaze. Once selected, the grasp is automatically executed via a predefined grasping sequence, eliminating the need for one-to-one motion mapping.
The grasping assistance system is implemented using ROS2 to control a Kinova Gen 3 robotic manipulator, with a Meta Quest Pro virtual reality headset providing the user interface. Additionally, the teleoperation system offers visual feedback from cameras in the manipulator's workspace, displayed through the head-mounted display, and incorporates a collision avoidance system to prevent unintended impacts.
A user study was performed with 30 participants using the developed system to compare the usability, workload, and performance of the grasping-assisted teleoperation with pure teleoperation (motion mapping). The study asks the operator to perform a pick-and-place task featuring four different objects in a specified order within the allotted time. Each participant performed the task with both pure teleoperation and grasping assistance modes in random order, and then completed questionnaires attempting to measure the usability of each system and measure their experienced workload. Results show that grasping assistance significantly reduces users' workload, but also leads to lower performance metrics with respect to pure teleoperation. The performance loss could be attributed to the implemented grasp planner. Therefore, a gaze-enabled grasping assistance framework such as the one presented in this thesis has the potential to reduce the workload experienced by users and improve performance metrics over standard motion mapping-based direct teleoperation frameworks
Artisanship in a post-industrial present: A physio-biological framework for restorative design artifacts
No full textOver billions of years, organisms have evolved from single cell organisms into the human species of today. That process shaped the physiology and psychology of the human species. While each person is unique, a product of each individuals experiences and specific genetic endowments, there exists universal features that are innate in the biology of humans. One aspect of this is our brain, a unique organ which has evolved through thousands of generations, and through countless interactions with our environments into a mechanism for our species survival. This evolutionary process created a deep innate relationship between humanity and our natural environments.
When modernism emerged at the turn of the 20th century, it fundamentally changed architecture. The economics of mass production mingled with advancements in medical reasoning to produce an architecture of efficiency. Architects such as Adolf Loos, Le Corbusier, and Alvar Alto translated the sterility and medical principles of the sanatorium into housing and beyond, producing an architecture founded on the principles of air and light as essential elements to health, while peeling architecture away from the “humid ground where disease breeds” as defined by Le Corbusier. Large windows, rooftop terraces, and spotless interiors crafted light filled spaces and spotless environments, perfect for the air and sun cure against tuberculosis, but which increasingly separated individuals from the ground humans have evolved to thrive in. Architecture shed the rich visual complexity, naturalistic illusions, and fluid interior exterior relationships of historic architectures, replacing it with a sterile incubator, targeted toward contemporary concepts of health.
Modernist architectural advancements led to a sterility that has permeated modern architectures, producing a cognitive discord that is actively harmful to individuals. Researchers in neuroscience and environmental psychology have sought to understand this discord, producing studies which seek to better identify the underlying cognitive mechanisms that inform these interactions. Designers in turn have developed frameworks for applying this research to design for well-being. This thesis proposes a framework for restorative design principles, and advocates the harnessing of digital fabrication technologies to produce restorative artifacts for well-being. Through the development of a framework specifically tailored to the production of digitally fabricated artifacts, this thesis proposes a methodology for generating restorative environments through informed design. The artifacts presented in this thesis demonstrate the application of restorative principles through digitally fabricated artifacts, advocating the adoption of a new architectural language for restorative, evolutionarily informed design
IN BETWEEN LAND AND SEA: Adaptive Redevelopment of the Indigenous Fishing Villages at Mumbai’s Coastal Fringes
No full textArchitecture is often understood through the spaces it produces, but its more significant role lies in framing the relationships between people, economies, and environments. When these relationships are disrupted by ecological change and urban expansion, the focus of architecture shifts from form to the conditions that allow communities to endure.
In the city of Mumbai, this shift is most visible along the coastline, where reclamation, large-scale infrastructure, and speculative real estate have steadily eroded ecological systems. Within this changing landscape, the fishing villages of the Koli community, the city's native inhabitants, continue to function as active settlements that support both livelihoods and cultural practices, even as they are reclassified as informal and placed under pressure from redevelopment.
This thesis proposes a framework that responds to the challenges faced by the Koli community through an integrated approach. Ecological restoration is established as the foundation, focusing on mangrove regeneration, wetland protection, and the preservation of tidal flows. Economic resilience is addressed through cooperative infrastructure, including fishing hubs, repair yards, and storage facilities, which strengthen small-scale fishing practices. Cultural presence is supported through plazas, markets, and promenades that keep Koli life embedded within the public realm of the city. Through this lens, the thesis reframes the coastline of the Khar-Danda Village as a shared edge where ecological systems, livelihoods, and cultural practices are sustained together
Reclaiming Absence: Building collective futures in Ontario's Gravel Belt
No full textOntario’s gravel mining belt stretches across vast swaths of land, leaving behind a fractured geography of extraction voids that scar ecosystems, disrupt fertile farmland, and give rise to monotonous suburban sprawl. Since the early 2000s, the Greater Toronto Horseshoe Area has welcomed nearly 100,000 new residents each year, with 86% of this growth shaped by low-density, car-centric development. This expansion continues to encroach on agricultural land, intensifying ecological imbalance and threatening long-term food security.
This extractive form of urbanism treats Ontario’s rural terrain as a consumable resource to fuel the material needs of metropolitan expansion. These landscapes, often dismissed as post-industrial or peripheral, are the frontlines where the converging crises of climate change, land commodification, and environmental degradation manifest most visibly. Yet, architectural discourse remains largely silent on this issue, overlooking the spatial politics of gravel pits and the suburban paradigms they perpetuate. Increasingly subjected to gridded, cartesian systems of control, these territories are erased of their histories and stripped of their potential futures.
This project responds to a moment of heightened urgency, marked by a housing crisis along with global supply chain disruptions, resurgent push for domestic extraction, and deepening climate precarity. Scholars across architecture, geography, and environmental humanities, such as Pierre Bélanger’s articulation of the “Extraction Empire”- have begun exposing the global entanglements of resource infrastructures. Within this critical discourse, this project will push for a growing momentum around design strategies that resist extraction and prioritize repair.
Envisioning a reclamation corridor across adjacent gravel pits. Structured as dense, reconfigured suburban fabrics centered around housing, food production, and ecological regeneration. This future oriented design reimagines the suburban ideal by coupling resilient infrastructure with regenerative land use, transforming extraction voids into productive terrain of renewal. Ultimately, it proposes a new kind of productive suburban belt that counters sprawl while fostering ecological stewardship and collective belonging through a shared sense of place
Development of Lora Battery-Free Water Leak Detection
No full textThis study explores the development of a battery-free water leak detection system that
leverages energy harvesting sensors and LoRa (Long Range) communication to overcome the
limitations of Bluetooth Low Energy (BLE) technology. While BLE offers low power
consumption, its range is limited to approximately 50 meters, making it unsuitable for wide
area monitoring. In contrast, LoRa provides transmission distances of up to 10 kilometres and
excellent indoor wall penetration, enabling broader scalability for smart infrastructure
applications. The goal of this research is to integrate LoRa modules into a self-powered sensing
platform, eliminating the need for conventional batteries or wired power sources.
However, the transition to a battery-free system introduces a key challenge: the LoRa module
requires high peak currents, often exceeding 100 mA, for successful activation and data
transmission, which electrochemical energy harvesting devices cannot directly supply.
Experimental testing showed that single energy harvesting cells failed to activate the LoRa
chip due to insufficient current, despite producing sufficient open-circuit voltage. Attempts to
connect sensors in series or parallel offered partial improvements but still lacked the required
stability and power density to sustain beaconing. These issues were further compounded by
mismatched performance between cells and high internal resistance, limiting energy transfer
efficiency.
To overcome power limitations, the system integrated a DC-DC boost converter and a 100 mF
supercapacitor to store and deliver energy in short bursts for LoRa transmission. Enhancements
in sensor design and enclosure durability improved activation speed and energy reliability.
Electrical tests confirmed efficient energy use and successful LoRa beaconing, demonstrating
the feasibility of battery-free, long-range leak detection for scalable, low-maintenance
monitoring
Spatiotemporal Variability in Groundwater–Surface Water Exchange Within a Perennial Stream: Alder Creek, Southwestern Ontario
No full textGroundwater discharge plays a crucial role in sustaining streamflow within creeks and rivers year-round while also supporting the aquatic life that live in them. However, due to numerous external pressures such as increased groundwater usage, changes in land uses, and climate change, these water bodies are under increased strain, putting increased emphasis on the need to protect and preserve them. To do this requires an increased understanding of groundwater-surface water interactions, which are complex processes that are challenging to accurately identify and quantify.
This work seeks to strengthen understanding of these complex processes. This involved the application of numerous small-scale techniques related to temperature readings, infrared imaging and hydraulic gradients to locate zones of groundwater discharge during reconnaissance of a moderately sized watershed to identify suspected gaining reaches for further study. At these identified study sites, detailed studies were completed to verify the reconnaissance results, quantify the groundwater-surface water exchange and assess its seasonal and temporal variability. This was done through the application of a combination of techniques, which involved monitoring hydraulic gradients, estimating streambed hydraulic conductivities, using temperature profiles and Darcy’s law to estimate groundwater fluxes, developing flow nets of study reaches, and performing differential stream gauging.
The reconnaissance proved effective at identifying signs of groundwater discharge throughout the watershed, based on clusters of cold streambed readings and infrared imaging differentiating groundwater discharge near and along the streambank from their surroundings based on temperature contrasts. The reconnaissance ultimately led to the identification of two sites exhibiting groundwater discharge conditions. At these study sites, groundwater discharge conditions were confirmed based on upward hydraulic gradients, upward Darcy fluxes and largely upward temperature profile fluxes, in depth follow up infrared imaging, and differential stream gauging identifying gaining conditions. Based on the point scale techniques of Darcy fluxes and temperature profile fluxes, groundwater-surface water exchange was found to exhibit similar spatial patterns with groundwater discharge appearing often highest in the areas of the study reaches where discharge was identified during the reconnaissance while signs of recharge were also found, highlighting the spatial variability along the reaches of study.
While effective at assessing spatial variability, these point measurement techniques were unable to accurately quantify groundwater discharge because they greatly underestimated the benchmark of differential stream gauging. This was attributed to the point measurement technique’s ability to only account for the vertical component of groundwater discharge, which was found to be small, indicating a significant alternative source of groundwater discharge. Based on a lack of instrumentation immediately at the streambanks, and visible discharge at some streambank locations, the discrepancy was attributed to groundwater discharge near the streambanks. Flow nets were initially unsuccessful in accounting for this significant component of groundwater discharge, which was attributed to the inability to accurately represent the high hydraulic conductivities near the streambank because of limited field data. When applying a higher, but reasonable, hydraulic conductivity value, the estimates of discharge were much more in line with differential stream gauging estimates, suggesting a significant component of groundwater discharge entering near the streambank.
Groundwater-surface water exchange was also found to be influenced by temporal variability, as seen by the increase in groundwater discharge measured between the winter and summer using the point measurement techniques. Hydraulic conductivities were influenced by changes in water viscosity, while bi-weekly and continuous monitoring of vertical and horizontal hydraulic gradients indicated the presence of groundwater discharge conditions and showed variability with time. Continuous datasets provided even greater insight, including identifying seasonal trends and the reversal of hydraulic gradients in responses to extreme flow events. Continuous monitoring, though differential stream gauging, also indicated variability in groundwater-surface exchange over the overall gaining stream reach. These results highlight the importance of considering variability when assessing groundwater- surface water interactions. The findings of this study make clear the significant complexity that exists with regards to groundwater-surface water interactions, and the many challenges that must be considered in order to better comprehend these processes
“I am in total control in my kitchen”: Food Safety Risk Perceptions of Independently Living Older Adults in Southern Ontario, Canada
No full textBackground: Foodborne illness is a significant global public health concern. Older adults are particularly vulnerable to foodborne illness due to age-related physiological changes, including weakened immune systems and chronic health conditions. In Canada, approximately four million cases of foodborne illness occur each year, resulting in over 240 deaths. While the aging population is rapidly growing, there is limited research on how older adults who live independently perceive and manage food safety risks. The overall aim of the thesis was to understand how independently living persons aged 65 and older, living in Southern Ontario (Kitchener-Waterloo, Cambridge, Guelph, and Woodstock) perceive and mitigate their risks of foodborne illness in their home environments. Specifically, the objectives were to explore: (i) how and why these individuals perceive their risk of developing foodborne illness, and (ii) whether these individuals follow recommended food safety practices and why or why not.
Methods: I conducted 14 semi-structured interviews with persons aged 65 and older, who live independently in Southern Ontario, speak English, and are primary food preparers in their households. Participants were primarily recruited using flyers at community centres for older adults, a health fair hosted at one of these centres, the Schlegel-UW Research Institute for Aging, libraries, and religious institutions. The interview guide was informed by the World Health Organization’s Five Keys to Safer Food. Each interview lasted 45-60 minutes and was conducted in person (n=10) or virtually (n=4). In-person interviews were audio recorded using Microsoft Teams, while virtual interviews were both audio and video recorded using Zoom, and live transcription was enabled on both platforms. I manually transcribed each recording verbatim and carefully revised the auto-generated transcriptions for accuracy. This study used a post-positivist and interpretive theoretical orientation. I analyzed the data using a combination of inductive and deductive approaches through reflexive thematic analysis, following Braun & Clarke’s six-phase process.
Results: Four themes were developed using an inductive approach based on the interviews with older adults: (1) Trusting my own cooking, (2) Doing what I’ve always done, (3) Being conscious of minimizing food waste, and (4) Cooking is a chore. Each theme encompassed subthemes that illuminated their nuanced perspectives and experiences. Participants expressed strong trust in their own food handling practices at home, which contributed to their perception of being at low risk for foodborne illness. They believed that preparing healthy meals makes their food naturally safe, leading them to believe that illness is unlikely to affect them. They engaged in varied food handling practices; some followed recommended guidelines, while others deviated, such as not using a food thermometer. Their practices were shaped by long-standing habits, experience, and reliance on both their food safety knowledge and their social networks. Participants described shopping and food preservation strategies aimed at minimizing food waste and costs, which resulted in neglecting best practices. In addition, limited kitchen space affected their food choices and storage practices. Reduced motivation to prepare meals and physical limitations prompted them to adjust their preparation methods and rely on convenience.
Conclusion: This is the first study in Canada to explore older adults’ perceptions of food safety risks using semi-structured interviews. While participants demonstrated solid food safety knowledge, they perceived themselves at low risk for foodborne illness in their homes. The findings highlight the need for education and awareness of specific food handling practices. This study provides practical guidance for public health professionals and senior care organizations to develop tailored resources that promote safe food handling, support older adults’ independence, and bridge the gap between knowledge and practice to reduce their risk of foodborne illness
Towards Honest, Practicable and Efficient Private Learning
No full textProtecting our personal information is a major challenge in today's data-driven world. When scientists and companies analyze large datasets, they need a way to ensure our individual privacy isn't compromised. This thesis focuses on Differential Privacy, a powerful, mathematical guarantee that places a strict, verifiable limit on how much personal information can be leaked, even if an attacker has the worst-case advantage. Researchers have developed various sophisticated algorithms to accomplish useful tasks, like building machine learning models or generating realistic synthetic data, while maintaining Differential Privacy. Crucially, these operations must be conducted within a predetermined, strict limit, often referred to as the "privacy budget." This budget mathematically quantifies the total acceptable loss of privacy for the entire process, enforcing a crucial trade-off between data utility and individual protection. All routine procedures of the machine learning pipeline, including data cleaning, hyperparameter tuning, and model training, must be performed within the budget. Several tools can perform these tasks in disjunction when the dataset is non-private. However, these tools do not translate easily to differential privacy and often do not consider the cumulative privacy costs. In this thesis, we explore various pragmatic problems that a data science practitioner may face when deploying a differentially private learning framework from data collection to model training. In particular, we are interested in real-world data quality problems, such as missing data, inconsistent data, and incorrectly labeled data, as well as machine learning pipeline requirements, including hyperparameter tuning. We envision building a general-purpose private learning framework that can handle real data as input and can be used in learning tasks such as generating a highly accurate private machine learning model or creating a synthetic version of the dataset with end-to-end differential privacy guarantees. We envision our work will make differentially private learning more accessible to data science practitioners and easily deployable in day-to-day applications
Polynomial Controllers for Optimal Trajectory Matching with Stability Guarantees
No full textWe formulate a trajectory matching problem in which a set of reference trajectories for a plant is given, and a control law that causes the plant’s trajectories to be as close as possible to the reference trajectories is desired. These trajectories might be generated by an implicit controller such as a model predictive control (MPC) algorithm or manually chosen by a user. This thesis presents a nonconvex optimization approach for solving the trajectory matching problem that generates explicit polynomial controllers. The value of this approach is that the explicit control laws it generates are simpler to implement, and can be used for stability analysis. Additionally, the method presented in this thesis guarantees local stability of the generated controller by ensuring local contractivity towards the generated trajectories. This thesis presents several theoretical results that justify the method described here. Firstly, a proof that the local contractivity constraints used to ensure local stability can be expressed as a set of matrix inequalities is presented, which turns an infinite set of constraints into a finite one. Secondly, a theorem that describes how symmetries in the trajectory matching problem correspond to symmetries in its solution is presented and proven, which enables a reduction in the control design problem size and resulting solution. Finally, this thesis demonstrates the method it describes on two example problems motivated by real-world applications. The first of these is stabilization and disturbance recovery for a single-machine infinite-bus (SMIB) power system, and the second is a lane change manoeuvre for Dubin’s vehicle, a simple vehicle model. In each case, the reference trajectories are generated by MPC