Theses

Permanent URI for this collectionhttps://uwspace.uwaterloo.ca/handle/10012/6

The theses in UWSpace are publicly accessible unless restricted due to publication or patent pending.

This collection includes a subset of theses submitted by graduates of the University of Waterloo as a partial requirement of a degree program at the Master's or PhD level. It includes all electronically submitted theses. (Electronic submission was optional from 1996 through 2006. Electronic submission became the default submission format in October 2006.)

This collection also includes a subset of UW theses that were scanned through the Theses Canada program. (The subset includes UW PhD theses from 1998 - 2002.)

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Grounded or Guessing? An Empirical Evaluation of LLM Reasoning in Agentic Workflows for Root Cause Analysis in Cloud-based Systems
(University of Waterloo, 2026-01-16) Riddell, Evelien
Root cause analysis (RCA) is essential for diagnosing failures within complex software systems to ensure system reliability. The highly distributed and interdependent nature of modern cloud-based systems often complicates RCA efforts, particularly for multi-hop fault propagation, where symptoms appear far from their true causes. Recent advancements in Large Language Models (LLMs) present new opportunities to enhance automated RCA. In particular, LLM-based agents offer autonomous execution and dynamic adaptability with minimal human intervention. However, their practical value for RCA depends on the fidelity of reasoning and decision-making. Existing work relies on historical incident corpora, operates directly on high-volume telemetry beyond current LLM capacity, or embeds reasoning inside complex multi-agent pipelines---conditions that obscure whether failures arise from reasoning itself or from peripheral design choices. In this thesis, we present a focused empirical evaluation that isolates an LLM's reasoning behaviour. We design a controlled experimental framework that foregrounds the LLM by using a simplified experimental setting. We evaluate six LLMs under two agentic workflows (ReAct and Plan-and-Execute) and a non-agentic baseline on two real-world case studies (GAIA and OpenRCA). In total, we executed 48,000 simulated failure scenarios, totalling 228 days of execution time. We measure both root-cause accuracy and the quality of intermediate reasoning traces. We produce a labelled taxonomy of 16 common RCA reasoning failures and use an LLM-as-a-Judge for annotation. Our results clarify where current open-source LLMs succeed and fail in multi-hop RCA, quantify sensitivity to input data modalities, and identify reasoning failures that predict final correctness. Together, these contributions provide transparent and reproducible empirical results and a failure taxonomy to guide future work on reasoning-driven system diagnosis.
Enhanced Performance and Stability of Planar Heterojunction Solar Cells via Hole Transport Layer Engineering and Low-Cost Fabrication
(University of Waterloo, 2026-01-16) Habibzadeh, Elaheh
Global energy demand has grown extensively in recent decades, and it has continued to rely on fossil fuels that are accompanied with environmental concerns. This has intensified the research for renewable energy alternatives with solar power standing out as a leading candidate due to its abundance, scalability and rapidly declining costs. As photovoltaic (PV) technologies have evolved significantly, their widespread adoption continues to face barriers in efficiency, stability and manufacturing costs. While inorganic semiconductors such as crystalline silicon remain dominant due to their favorable band gap and long-term stability, hybrid solar cells such as organic–inorganic heterojunction solar cells have gained increasing attention for their ability to combine the tunability and ease of processing of organics with the superior charge transport and stability of inorganics. In this work, we have investigated the stabilization of planar heterojunction solar cells through the incorporation of dimethyl sulfoxide (DMSO) into PEDOT:PSS-based hole transport layers (HTLs). The acidic and hygroscopic nature of PEDOT:PSS is a well-known source of device instability, leading to accelerated degradation under ambient conditions. By employing DMSO as a cosolvent alongside ethylene glycol and methanol, this work demonstrates that optimized modification enhances electrical conductivity, reduces recombination, and markedly improves stability. Devices incorporating DMSO-treated PEDOT:PSS films retain nearly 89.4% of their initial efficiency after 72 hours of ambient storage, in contrast to the sharp decline seen in control devices without DMSO. Atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) confirm improved surface morphology and a favorable redistribution of conductive domains. The findings establish DMSO modification as a practical, cost-effective strategy for producing more inherently resilient heterojunction solar cells. Following these insights, we introduce dimethyl sulfone (DMSO₂) as a solid-state additive for PEDOT:PSS films. Unlike liquid cosolvents, DMSO₂ crystallizes upon drying, inducing a unique reorganization of polymer microstructures that enhances phase separation and alignment of conductive PEDOT chains. The resulting films exhibit superior conductivity, improved charge transport, and greater stability against moisture induced degradation. Devices fabricated with DMSO₂-doped PEDOT:PSS achieve efficiencies up to 15.5% (EMD2) and an average T80 of ∼913 h of ambient storage (ED2), a substantial improvement over conventional treatment. Through a combination of external quantum efficiency (EQE), AFM, and conductivity analyses, this work highlights the ability of DMSO₂ to simultaneously enhance efficiency and extend ambient storage longevity, offering an environmentally benign and scalable pathway for advancing PEDOT:PSS-based solar technologies. We also address the challenge of electrode optimization by introducing a rapid and low-cost method of shadow mask fabrication by desktop 3D printing. While electrode geometry is critical to current collection efficiency, series resistance reduction, and overall photovoltaic performance, traditional fabrication techniques are expensive, time-consuming, and inflexible. By employing polyethylene terephthalate glycol-modified (PETG) filaments for 3D printing, this study demonstrates a streamlined approach to fabricating custom shadow masks for top electrode manufacturing in hours rather than weeks. Comparative testing of three geometries (comb-like busbar, central busbar, and crossed busbar) shows that the central busbar design achieves superior efficiency enhancement by 21.62% and improves the fill factor by reducing resistive losses and balancing optical transparency. This work illustrates how low-cost additive manufacturing can democratize device prototyping, accelerate design iterations, and lower research and production costs without compromising performance. In summary, this dissertation presents a cohesive exploration of strategies to improve efficiency, stability, and fabrication simplicity of planar heterojunction solar cells. Through targeted material modifications and innovative fabrication methods, the studies collectively highlight pathways to bridge laboratory innovation with commercial feasibility. Together, these contributions underscore the critical role of polymer modification and accessible fabrication in the evolution of next-generation solar cells, with the ultimate goal of advancing the prospects of clean, scalable, and sustainable energy technologies.
Cellulose Nanocrystal Coated Paraffin Wax Coating for Fog and Dew Water Harvesting
(University of Waterloo, 2026-01-16) Yan, Riyao
Fresh water scarcity is an urgent global issue. A sustainable and renewable method is harvesting atmospheric water, among which fog and dew water can be passively collected onto a surface. The efficiency of such collecting systems depends critically on the wetting and dynamic behavior of water droplets on the surface. Common approaches to modify surface topography and hydrophobicity often relies on lithographic, plasma, or fluoropolymer-based methods that are costly, complex, and environmentally unsustainable. In contrast, this work proposes a novel, simple, and bottom-up approach for producing surface with functional coatings through cellulose nanocrystal (CNC)–stabilized Pickering emulsions. The first part of the study focuses on understanding the stabilization and formulation behavior of CNC-based oil-in-water emulsions under varying CNC concentration, ionic strength, and oil-to-water ratios. The resulting interfacial coverage and droplet packing efficiency govern the size and assembly of the wax microparticles, allowing fine control of surface roughness and wettability. Coatings derived from these particles exhibit a wide range of wetting states—from hydrophilic to superhydrophobic—depending on CNC surface coverage and aggregation state. In the second part, these coatings are evaluated for fog and dew water collection, emphasizing the differences between liquid water deposition and humid air condensation on surface. The results show that overall water collection performance is governed by two coupled processes: the rate at which moisture is captured on the surface and the efficiency with which the accumulated water is removed. Previous studies have shown that while superhydrophobic surfaces exhibit superior droplet removal efficiency, their performance can degrade under continuous usage due to partial loss of superhydrophobicity and water film formation. On the other hand, surfaces with balanced nucleation density and drainage efficiency are more desirable, especially for condensation. This research establishes a biobased, PFAS-free, and scalable fabrication route for tailoring surface wettability using CNC-stabilized emulsions. Beyond atmospheric water harvesting, the insights gained here into interfacial assembly and condensation dynamics under realistic humid-air conditions contribute broadly to the design of sustainable coatings for humidity control and anti-fogging/anti-icing applications.
Effects of Stabilizing Binder on the Formability, Microstructure, and Mechanical Performance of Wet Compression Molded Unidirectional Non-Crimp Fabric Composites
(University of Waterloo, 2026-01-16) Miranda Portela, Renan
Wet Compression Molding (WCM) with highly reactive resins is a manufacturing process capable of high-volume production that has recently gained interest in the automotive industry as an alternative to traditional methods for producing structural components. These components are subject to high loads and may experience impact loads during service; therefore, to achieve the desired mechanical properties and performance requirements, the structural components may require several layers and a significant amount of resin. For typical WCM processes utilizing molds with deep cavities, resin management can be challenging as the fabric stack may drape prematurely due to the mass of the resin; however, the use of binder-stabilized fabric can overcome this problem by enhancing the fabric bending stiffness. While the influence of stabilizing binder on the permeability of various fabrics and the flow characteristics of different resins has been previously studied, its impact on void formation and mechanical performance is less understood. This study focuses on the effects of stabilizing binders on the intra-ply draping mechanisms of wet, unidirectional, non-crimp fabric (UD-NCF), as well as on the microstructure and mechanical performance of the UD-NCF composite fabricated via WCM, which comprises PX35-UD300 carbon fiber fabric and EPIKOTE resin 06150 snap cure epoxy resin, through physical experiments. The objectives of this study are to investigate the influence of the stabilizing binder on the formability of infiltrated carbon-fiber UD-NCF (including membrane behaviour, bending, and compaction), to examine its effects on the microstructure and mechanical performance of UD-NCF composites manufactured via WCM, and to assess the impact of the stabilizing binder on the energy-absorption performance. For Objective 1, the UD-NCF carbon fiber was characterized through a series of physical experiments, including membrane, bending, and compaction tests. An infiltrated bias-extension test setup was used to analyze the membrane mechanism, a rheometer bending test setup was employed to examine the bending mechanism, and a punch-to-plate setup was utilized to study the compaction mechanism. The fabric infiltration was found to influence the membrane and bending behaviors by reducing the friction between the carbon fiber and the stitching yarns, which consequently decreased the membrane stiffness and the bending stiffness up to 30%. However, impregnation was found to have no significant impact on the compaction response due to the low friction of the carbon fibers. In contrast to fabric impregnation, the pre-activation of the stabilizing binder was found to affect all three draping mechanisms by increasing fiber/fiber and fiber/yarn friction, thereby increasing membrane stiffness by up to 100% and bending stiffness by up to 50%. For Objective 2, flat UD-NCF composite panels were fabricated by WCM to examine how the stabilizing binder and its state, as well as the vacuum application to the mold and its duration, influence the formation of voids and mechanical properties. It was observed that the use of binder-stabilized fabrics decreased the void content of WCM parts by up to 70%, likely due to reduced relative layer movement and lower air entrapment. The void size decreases further when a vacuum is applied to the mold for more than 20 seconds, which partially removes air inside the mold. This reduction in void size leads to an increase in interlaminar shear strength. Additionally, applying a vacuum enhances preform compaction, resulting in more consistent panel thickness and a higher fiber volume fraction (FVF). For Objective 3, UD-NCF composite hat channels were fabricated by WCM to examine the influence of the stabilizing binder and vacuum application on energy absorption during axial crush experiments. The use of binder-stabilized fabric and vacuum increased energy absorption; however, this increase was not statistically significant, possibly due to the high FVF of the components. The WCM hat channels achieved energy absorption levels comparable to those of similar hat channels comprising the same constituents and ply stacking sequence and fabricated by high-pressure resin transfer molding (HP-RTM) in a previous study. The WCM hat channels also showed a similar brittle fracture failure mode to the HP-RTM hat channels. The main results of this investigation include a new dataset on the viscous draping mechanisms of the binder-stabilized UD-NCF. Additionally, mechanical tests provided strong evidence of the influence of the stabilizing binder on the mechanical performance of the UD-NCF composites. These results indicate the feasibility of using the WCM process as an alternative to HP-RTM in the manufacturing of structural components.
Hybridizable discontinuous Galerkin methods for coupled flow and transport systems
(University of Waterloo, 2026-01-16) Yackoboski, Elizabeth
In this thesis, we propose and analyze hybridizable discontinuous Galerkin methods for coupled flow and transport systems. Such systems may be used to model real-world scenarios in which a fluid contaminant travels through another medium. Common applications include environmental engineering problems and biochemical transport. This thesis focuses on the Stokes/Darcy-transport and Navier--Stokes/Darcy-transport systems. We consider a two-way coupling between each flow and transport problem: the solution to the flow problem is directly involved in the transport problem, and the solution to the transport problem appears in the flow problem through a parameter function. In each of our considered systems, the flow problem is stationary while the transport problem is time-dependent. The resulting coupled flow and transport systems are quasi-stationary in the sense that the evolution of solutions to the flow problems over time is driven by the transport problem. Our numerical schemes use a time-lagging method in which the flow and transport problems are decoupled and solved sequentially using hybridizable discontinuous Galerkin methods. This decoupling allows us to establish separate conditions on the discrete flow problem and on the discrete transport problem such that solutions to the combined scheme converge at optimal rates. Moreover, we show how existing results on related discrete flow problems and on the discrete transport problem may be exploited for efficient analysis of the coupled systems. We present this approach in a general setting, and illustrate its use through the specific examples of the Stokes/Darcy-transport and Navier--Stokes/Darcy-transport systems. For all schemes, we establish the existence of unique numerical solutions over a considered time interval. We prove optimal rates of convergence in space and time, and provide numerical examples to support the theory.
UringCL: A Lightweight io_uring Convergence Layer for Adoption in Legacy Event Loops
(University of Waterloo, 2026-01-16) Afsharian, Armin
High-performance network servers depend on efficient I/O mechanisms to manage thou- sands of concurrent connections with minimal latency and overhead. While traditional readiness-based interfaces (e.g., select, poll, epoll) notify applications when I/O oper- ations can proceed, they still require synchronous system-calls to execute the operations. This synchronous requirement causes frequent user–kernel transitions, which limits scala- bility under heavy load. In contrast, the io uring interface offers a fundamentally different approach by providing a completion-based I/O model that minimizes system-call overhead and enables true asynchronous data transfer. Although the performance benefits of io uring are well established in storage systems, its integration into high-throughput network applications remains limited. This thesis aims to bridge this integration gap by making the adoption of io uring accessible and provid- ing a structured vehicle for evaluating its performance in network-bound environments. To this end, the io uring Convergence Layer (UringCL) is presented to transparently map the synchronous I/O calls of readiness-driven applications onto asynchronous io uring operations. The UringCL simplifies initialization, event handling, and data transfer while preserving the existing control flow of legacy applications, allowing for incremental migra- tion toward completion-based I/O without major redesign. The UringCL architecture facilitates the practical integration of io uring into estab- lished network architectures and provides a consistent framework for measuring its impact on throughput, latency, and CPU efficiency. Experimental results demonstrate significant performance advantages over traditional models. In bulk-transfer workloads, the system delivers up to 40% higher throughput than epoll due to superior batching capabilities. In request-response scenarios involving Memcached, the integration achieves higher peak throughput and maintains significantly lower and more stable tail latency under heavy load. Furthermore, UringCL achieves these benefits with negligible overhead, proving that completion-based I/O can be adopted seamlessly to enhance the efficiency of modern net- work servers.
GASTON: Graph-Aware Social Transformer for Online Networks
(University of Waterloo, 2026-01-16) Wloch, Olha
Online communities have become essential digital third places for socialization and support, yet they also possess toxicity, echo chambers, and misinformation. Mitigating these harms requires computational models that can understand the nuance of online interactions to accurately detect harmful content such as toxicity and norm violation. This is difficult because the meaning of an individual post is rarely self-contained; it is dynamically constructed through the interplay of what is written (textual content) and where it is posted (social structure). We require models that effectively fuse these two signals to generate representations for online entities such as posts, users, and communities. Current approaches often treat these different signals in isolation: text-only models analyze content but miss the local social norms that define acceptable behavior, while structure-only models map relationships but ignore the semantic content of discussions. Recent hybrid approaches attempt to bridge this gap but some rely on simple text averaging mechanisms to represent a user and a community, and in so doing flatten the rich, norm-defining identity. To address this limitation, this thesis proposes GASTON (Graph-Aware Social Transformer for Online Networks), a graph learning framework designed to capture the essence of online social networks. It does so by modeling connections between all online entities, such as users, communities, and text. This makes it possible to ground user and text representations in their local norms, providing the necessary context to accurately classify behaviour in downstream tasks. The heart of our solution is a contrastive initialization strategy which pre-trains community representations based on user membership patterns, effectively capturing the unique signature of a community's user base before the model processes any text. This allows GASTON to distinguish between communities (e.g., a support group vs. a hate group) based on who interacts there, even if they share similar vocabulary. We evaluate GASTON across a diverse set of socially-aware downstream tasks, including mental health stress detection, toxicity scoring, and norm violation detection. Our experiments demonstrate that GASTON outperforms state-of-the-art baselines, particularly in tasks where social context is critical for classification, such as detecting norm violations. Furthermore, we illustrate that these learned representations provide interpretable insights, offering a path toward user-empowered transparency in online spaces.
Transcending the Settled Ground: Mapping Obligations of Settler Architects in Canada
(University of Waterloo, 2026-01-16) Hu, Anita
This research begins with the recognition that architecture, as both a discipline and a practice, has never been neutral. The design process has long been entangled with histories of colonization, where land was surveyed and transformed into property. In Canada, these processes were instrumental in establishing a settler-colonial relationship to land, one that privileges extraction and productivity over reciprocity and care. This study asks how the architectural design process reproduces these colonial structures and how settler architects might begin to take responsibility for the histories that shape their work. In the outskirts of Sarnia, Ontario, an area known as Chemical Valley sits on the traditional territory of the Chippewa, Odawa, and Potawatomi peoples, collectively known as the Anishinaabeg. It is home to the Aamjiwnaang First Nations reserve and a dense concentration of petrochemical refineries. The term “Chemical Valley” dates back to 1947 as a symbol of national progress, but is now used by Aamjiwnaang First Nations and activists to draw attention to the negative impacts of this industrial corridor. The proximity between the two landscapes exposes how colonial systems of land use and resource extraction persist in shaping environmental and social conditions today. By tracing the evolution of architectural and planning tools, from early land surveys to contemporary zoning and professional standards, this research uncovers how these systems continue to define who has access to land and who bears the burden of its consequences. Through archival analysis and an examination of city planning and architectural practice, this work delineates how the design process itself has been used to legitimize and justify land dispossession. Acts of measuring and drawing are political gestures that determine what is seen, valued, and remembered. Confronting this legacy requires a reorientation of architectural practice, one that shifts toward methods grounded in care and reciprocity, prioritizing relationships with the land.
Addressing Informal Caregiver Burden: Technology and Toolkit for Medication Management in Older Adults
(University of Waterloo, 2026-01-16) Ghanem, Karyman Ahmed Fawzy
Background: Older adults with multiple chronic conditions often manage complex medication regimens. Age-related physical and cognitive impairments further complicate this process and increase the risk of medication errors and non-adherence. Informal caregivers, including family, friends, and neighbors, play a crucial role in supporting this process. However, many caregivers feel unprepared for the complex and time-consuming tasks involved in medication management. As a result, they may experience significant caregiver burden, which affects their emotional, social, financial, and physical well-being and can contribute to anxiety, poor self-care, sleep disruption, social isolation, or even suicidal thoughts. Objectives: 1. To evaluate the impact of an automated medication dispenser (AMD) on compassion fatigue, satisfaction, and medication administration hassles. 2. To develop a medication management toolkit to support family caregivers with medication management at home. Methods: Study one is a pilot mixed-methods study that recruited 7 pairs of family caregivers and their older care recipients. Caregivers completed the Family Caregiver Medication Administration Hassles Scale (FCMAHS) and the Professional Quality of Life Scale (ProQoL) at baseline, 2 weeks, and 3 months after implementing AMD in care recipients’ homes. Caregivers were interviewed before and after using AMD. The interviews were recorded, transcribed, and thematically analyzed. Study two is a qualitative study in which 16 family caregivers participated in focus group discussions to identify medication management challenges and solutions that will inform the development of the toolkit. Results: In study one, Friedman tests showed no significant change in FCMAHS subscale scores over time after Bonferroni correction (α =0.0125; all p > 0.0125). The total score (primary outcome) was assessed without correction (α = 0.05) and was not significant. Wilcoxon Signed-Rank Tests showed a similar pattern, except for a significant reduction in total score from baseline to 3 months (p=0.02). Both tests showed no significant change in scores for the subscales of ProQoL after Bonferroni correction (α= 0.0167); all p > 0.0167). Three themes emerged from the pre-intervention interviews: becoming a caregiver, approaches to support medication management, and caregiver experience and well-being. Four themes emerged from the post-intervention interview analysis: usability and functionality, experience with remotely delivered pharmacy services, caregiver experience and well-being, and impact on the caregiver–recipient relationship. Six themes emerged from study two: caregiver–recipient relationship and caregiving context; challenges with medication management; medication management strategies; non-medication management tasks; caregivers’ preferences for toolkit format and content; and additional support with medication management. Conclusion: Study one shows that the long-term use of AMD has the potential to be beneficial for caregiving burden related to medication management but is influenced by the caregiver’s adjustment period. Future research should verify these pilot findings. Study two shows that family caregivers manage medications across several domains in which they face challenges, including scheduling doses, supporting adherence, tracking medication supplies, and communicating with healthcare professionals. To assist with these tasks, caregivers often rely on simple and traditional tools and strategies.
Development Workflow Generation Methodology Applied to a Propulsion Supervisory Controller for Battery Electric Vehicles
(University of Waterloo, 2026-01-16) Rofiq, Henri
The increasing integration of software in modern vehicles has transformed the automotive industry, enabling advanced functionalities across the domains of safety, performance and user experience. However, the design and development of vehicle control systems is a complex process that requires familiarity with specialized tools and validation practices. These skills are typically not taught during university and thus, this thesis presents a comprehensive methodology for generating and implementing a control logic development workflow. The application of this methodology is demonstrated through its successful application to the design of a Propulsion Supervisory Controller (PSC) for deployment to a Cadillac LYRIQ, developed as part of the EcoCAR EV Challenge (EVC). The proposed workflow provides a structured approach to tackle software tool and hardware selection, requirements generation, software design principles, testing strategies and codebase maintenance considerations. Application of this workflow results in the generation of the UWAFT controls development methodology which uses the MathWorks (MATLAB/Simulink) toolchain and Speedgoat hardware, where the team developed software that was a “pipes and filters”, layered and component-based control architecture. UWAFT employed Agile-hybrid principles for the comprehensive development of requirements which originate from supplier documentation, team goals as well as safety analyses. Finally, software was integrated using version control via Git and emphasized comprehensive verification which includes extensive “-in-the-loop” (XIL) testing. Application of this methodology enabled UWAFT to achieve consistent and high-quality software development under resource constraints, leading to successful deployment and validation of vehicle control features such as torque management and directional control. Furthermore, the generated software also led to success at year-end competitions where the PCM team was able to successfully achieve a 3rd place finish. Beyond technical outcomes, the workflow improved collaboration, documentation and onboarding within the student team, bridging the gap between academic learning and industry-standard experience. An assessment of limitations and areas for future improvement is presented, including enhanced CI/CD automation, cross-project integration and adaptation of the workflow for internal combustion architectures. Overall, this research contributes a modular and educationally valuable framework that can be adopted by student design teams and research groups to produce reliable automotive control software.
A Sanctuary inspired by Gurbani in Gati Harike, Punjab: A Spiritual Journey of Awakening
(University of Waterloo, 2026-01-16) Devgan, Jasmine
This research investigates the profound connection between spirituality, architecture, and urban design, aiming to create built environments that express spiritual values and evoke deep presence, meaning, and emotional resonance. Drawing upon the universal teachings of Gurbani, the project translates the Elements of Creation and the energy of Chakras into a transformative spatial design language for a "Journey of Awakening." The thesis posits that humanity should strive for total consciousness, or Mukti (liberation), by transcending Trigun Maya to realize divine truth, emphasizing "truth in design" over mere aesthetics. The study explores how metaphysical principles can imbue built spaces with meaning, facilitating a journey from an "enslaved (under the impact of five vices: Lust, Anger, Greed, Attachment, and Ego driven by desires) to a free (filled with Divine Virtues) person" through experiential understanding of the five elements of nature and the practical implementation of divine wisdom. It argues that architecture plays a pivotal role in shaping emotions, behaviors, and consciousness, and that a lack of spiritually attuned design contributes to modern societal issues. Employing an interdisciplinary methodology spanning cultural history, philosophy, psychology, neuroscience, and phenomenology, this research examines the reciprocal relationship between human neural processing, architectural stimuli, and spiritual experiences. The proposed ISHQ-E-SAT (meaning "Love is Truth") sanctuary, an eco-sensitive retreat within the Harike Wetland, Punjab, exemplifies these principles. Its design organizes the site into seven chakra-aligned nodes, integrating the Five Elements, sacred geometry, Punjabi vernacular architecture, and symbolic elements. This fosters spiritual resonance, cultural rootedness, and community empowerment through sustainable, inclusive practices. Ultimately, this work seeks to enrich architectural practice, guiding individuals toward self-reconnection, spiritual awakening, and harmonious living with nature and humanity.
Altering Bodies, Altering Minds: Examining Essentialism, Gendered Discrimination and Violence, Racism, and Colonialism through Speculative Fiction Tropes
(University of Waterloo, 2026-01-16) Riley, Meghan
This dissertation examines the ways in which speculative fiction tropes simultaneously reinforce and challenge ideologies which uphold not only discourses about but also systems of domination, including racism, ethnocentrism, colonialism, and gendered violence. Further, the novum – the element within the text which distinguishes the world of the story from our own – and the resulting distance (Suvin 6) enables profound engagement with the lived experiences of being raced, gendered, and subordinated, while often resisting didacticism. However, it is that same distance which can lead to the repetition and circulation of insidious ideologies. I argue that it is these factors which make the genre of speculative fiction particularly generative as a postcolonialist, feminist literature, and for destabilizing students’ taking pervasive essentialist worldviews as a given so that they can critically engage with and critique the aforementioned ideologies in media. The analysis spans five chapters. The first chapter examines how the tropes of shapeshifting, cloning, transgenerational memory, and extreme longevity in Octavia E. Butler’s Wild Seed, Larissa Lai’s Salt Fish Girl, and Nnedi Okorafor’s Who Fears Death operate to center embodied knowledge and alternate ways of knowing and producing, serving as a challenge to Western rationalism as well as patriarchal and colonialist ideologies. Chapter two demonstrates how the speculative fiction tropes of pheromones, advanced brain alterations, genetic modification, extrasensory abilities, and an alien breeding scheme in Butler’s Lilith’s Brood and Fledgling foreground the ethics of consent in rape culture, medical care, and colonialism. Chapter three focuses on the role tropes such as shapeshifting, extrasensory abilities, parthenogenesis, and a third sex play in critiquing essentialism, gendered discrimination, and violence, but ultimately failing to imagine a future in which men are able to act beyond their biology or in which caregiving is not exclusive to people who can give birth. The fourth chapter examines and critiques the tendency of speculative fiction film and television to deny racialized alien characters reproduction, and if reproduction occurs, to deny these characters a stable and healthy family life – a denial which mimics cultural genocide and other colonialist practices. Further, the persistence of “scientific” racism, the ubiquitous reproduction of white bodies through a range of speculative fiction tropes such as doubling through cloning and time travel, and the valorization of white parents and children that occurs through speculative tropes is made clear. In the fifth chapter, I apply my analysis of the above to my recommendations on teaching a course which addresses these ideologies in speculative fiction media and invites students to consider the ways in which aspects of their worldview have been influenced by embodiment, the social construction of race and gender, etc.
Exploring the association between muscle mass and strength measures and hip geometry in males and postmenopausal females aged 50 and older with low bone mass.
(University of Waterloo, 2026-01-16) Graham, Connor
Background: Dual-energy X-ray absorptiometry (DXA) scans and hip structural analysis (HSA) software allow for the analysis of bone geometry in the proximal femur. Bone architecture is influenced by muscle, as described by the Utah paradigm, yet the specific muscle-bone geometry relationship remains poorly understood, thereby revealing a knowledge gap. Therefore, the investigation aimed to examine the relationship between lower limb muscle or strength measures and hip geometry, as measured by DXA scans, in a population of males and post-menopausal females aged 50 and above with low bone mass. Methods: We led a cross-sectional, exploratory secondary analysis of the baseline data from the Finding the Optimal Resistance Training Intensity For Your (FORTIFY) Bones trial. Statistical analysis was completed using R Studio (Version 4.4.2), wherein 24 multivariable linear regressions were developed using section modulus and buckling ratio of the femoral neck, intertrochanteric region and femoral shaft as dependent variables. Lower left limb lean soft tissue (LLLLST), muscle quality index (MQI), 30-second chair stand test and normalized knee extension strength were examined as independent variables in separate models for each dependent variable. All models were controlled for age, while only models using normalized knee extension strength or 30-second chair stand test were controlled for BMI. Results: In a sample of 324 participants (93% female, 83% Caucasian) descriptive statistics as mean (SD) were as follows: BMI 24.59 (4.33) kg/m2, normalized knee extension strength 85.91 (31.51) Nm, LLLLST 6.183 (1.2325) kg, MQI 13.68 (3.95) Nm/kg, 30-second chair stand test score 15.80 (4.33), femoral neck section modulus 1.187 (0.280) cm3, femoral neck buckling ratio 13.434 (2.948), intertrochanteric region section modulus 3.734 (0.936) cm3 , intertrochanteric region buckling ratio 9.612 (1.834), femoral shaft section modulus 2.091 (0.444) cm3, femoral shaft buckling ratio 3.149 (0.846). Models using LLLLST explained the greatest amount of variance of section modulus at the femoral shaft (Unstandardized ß=0.272, 95%CI [0.247 to 0.298]; R2=0.5840, p<0.001), intertrochanteric region (Unstandardized ß=0.520, 95%CI [0.460 to 0.581]; R2=0.4686, p<0.001) and femoral neck (Unstandardized ß=0.126, 95%CI [0.105 to 0.146]; R2=0.3147, p<0.001). Models using knee extension strength explained the second greatest amount of variance of section modulus at their respective sites. Specifically, models using normalized knee extensor strength explained 38.26% of section modulus variance at the femoral shaft (Unstandardized ß=0.00560, 95%CI [0.00434 to 0.00687]; R2=0.3826, p<0.001), 35.11% of section modulus variance at the intertrochanteric region (Unstandardized ß=0.0111, 95%CI [0.00832 to 0.01391]; R2=0.3511, p<0.001) and 18.22% of section modulus variance at the femoral neck (Unstandardized ß=0.00366, 95%CI [0.00273 to 0.00460]; R2=0.1822, p<0.001). Conclusion: Our findings indicate that the models using LLLLST and normalized knee extension strength moderately or strongly explain section modulus depending on the region of interest. The relationships illustrated here add to our understanding of the muscle-bone relationship, specifically by highlighting the muscle-bone geometry relationship. Future investigations should determine whether changes in lean soft tissue or strength result in changes in bone geometry within participants over time.
A proof-technique-independent framework for detector imperfections in QKD
(University of Waterloo, 2026-01-14) Nahar, Shlok
The security of Quantum Key Distribution (QKD) protocols is theoretically established using idealised device models. However, the physical implementations upon which practical security relies inevitably deviate from these ideals. This thesis develops a rigorous and versatile framework to address a subclass of such deviations: detector imperfections. This framework, termed ’noise channels’, is independent of security proof technique. This approach recasts imperfections as a quantum channel preceding an idealised measurement process. By granting the eavesdropper control over this channel, the security analysis is simplified to an ideal scenario, with the effects of the imperfections mathematically contained within a well-defined parameter. The utility and versatility of the framework are demonstrated through applying it to the postselection technique, and for phase error estimation. The application to phase error estimation is an improvement over past analyses which either assumed qubit detection setups, IID attacks, or required hardware modifications. We observe a remarkably high tolerance to imperfections when using the postselection technique. Finally, we extend the framework to address cross-round correlations, providing a methodology to prove security against detector memory effects such as afterpulsing and dead times. This work thus establishes a structured and powerful toolkit for analysing detector imperfections in practical QKD systems, unifying their treatment across different security proof techniques and advancing the development of robust implementation security.
Detection and Characterization of Viruses in the Environment Using Established and Novel Sequencing Approaches
(University of Waterloo, 2026-01-14) Nash, Delaney
Viruses play critical roles in both the environment and public health systems. This thesis integrates genomic sequencing methodologies to detect, characterize, and monitor viral diversity, advancing both fundamental ecological research and applied pathogen surveillance. Through three focused research projects, this work demonstrates how targeted and metagenomic sequencing strategies can address key knowledge gaps in environmental virology, plant pathology, and viral public health surveillance. The first objective (Chapter 2) was to develop and apply novel tiled-amplicon sequencing assays for Influenza A virus (IAV) H3N2 and respiratory syncytial virus (RSV) A in wastewater-based surveillance. These assays successfully recovered near-complete viral genomes from wastewater samples collected during the peak of the 2023/2024 respiratory virus season. Genomic coverage trends mirrored clinical case data within the associated public health region, validating the approach as a complementary tool to traditional clinical surveillance. Variant deconvolution analyses revealed distinct spatiotemporal patterns in variant distribution, demonstrating the capacity of these assays and bioinformatic tools to resolve community-level transmission dynamics and emerging viral lineages. The second objective (Chapter 3) extended this surveillance framework to the agriculturally significant Tomato brown rugose fruit virus (ToBRFV). A multiplexed tiled-amplicon assay was developed, achieving significant improvements in viral genome recovery compared to metagenomic RNA shotgun sequencing while reducing sequencing costs and resource requirements. ToBRFV clades circulating in Ontario wastewater were identified, including variants later recognized through global surveillance initiatives, underscoring the assay’s potential for early detection and the value of wastewater systems as environmental reservoirs for plant viruses. The third objective (Chapter 4) involved the assembly and characterization of the complete genome of a novel freshwater algal virus, Chrysochromulina parva virus BQ1 (CpV-BQ1). Using a hybrid Nanopore and Illumina sequencing strategy, a high-quality 165,454 bp genome was assembled and annotated, revealing hallmark nucleocytoplasmic large DNA virus (NCLDV) genes and diverse functional categories associated with viral replication, host manipulation, and capsid formation. This work offers important insights into viral infection of the ecologically important freshwater algal species C. parva. Moreover, it establishes a methodological framework for the complete sequencing, assembly, and annotation of algal virus genomes. Collectively, this thesis advances environmental virology and viral surveillance systems by developing scalable, sensitive, and cost-effective genomic workflows for virus detection and characterization in freshwater environments. By integrating virus ecology with applied public health and agricultural surveillance within a One Health framework, this work underscores the interconnectedness of environmental, human, and agricultural systems and provides practical guidance for future viral genomics research and pathogen monitoring programs.
The Forces Behind the Flux: Methane, Carbon Dioxide, and Nitrous Oxide Dynamics and Their Environmental Drivers in Restored Agricultural Wetlands
(University of Waterloo, 2026-01-14) Meinzinger, Shayna
Wetlands provide vital ecosystem services such as water filtration and flood mitigation but are also significant natural sources of greenhouse gases (GHGs), particularly methane (CH₄). This study examined seasonal and spatial patterns of CH₄, carbon dioxide (CO₂), and nitrous oxide (N₂O) emissions from seven restored agricultural wetlands in the Ontario portion of the Lake Erie Basin, focusing on diffusive and ebullitive flux pathways. Emissions were measured across four seasons, alongside water quality parameters used to identify key environmental drivers. Dissolved oxygen (DO) emerged as a strong driver of GHG fluxes, with lower DO concentrations consistently promoting higher CH₄, CO₂, and N₂O emissions. Duckweed cover also enhanced CH₄ production by creating anoxic conditions. GHG emissions peaked during summer months with heightened biological activity, while winter fluxes, though reduced, remained detectable, emphasizing the contribution of cold-season processes. N₂O emissions remained consistently low throughout the year. Across sites, methane emissions were generally low relative to natural temperate wetlands, except at one nutrient-enriched outlier (Site MA). Spatial variation within wetlands was minimal, suggesting that sampling from a single representative location may be sufficient for long-term monitoring. These findings show that restored agricultural wetlands can act as both carbon sinks and GHG sources depending on local biogeochemical conditions. By identifying major environmental controls on emissions, this study advances understanding of GHG dynamics in restored wetlands, informs efficient monitoring and modelling considerations, and strengthens national inventory and restoration policy development.
Negotiating Restoration through Representation: The role of visualization in the public process of Riverside Dam
(University of Waterloo, 2026-01-14) Polera, Jordana
As climate change intensifies ecological uncertainty and infrastructure risk, low-head dam removals have become sites where environmental, cultural, and political tensions converge. This thesis examines the case of Riverside Dam in Cambridge, Ontario (2008-2019), to explore how visualization acts not only as a tool of communication but as an active agent in shaping negotiations over the whether to remove, rebuild Riverside Dam. The Municipal Class Environmental Assessment (EA) for Riverside Dam including consultant drawings, City reports, and community responses based on eight “preferred alternative” designs for the dam. Visual materials play a decisive role in how potential futures are understood, aiding in understanding, participation, and decision-making. Drawings are political tools that can include or exclude voices, clarify or obscure impacts, and build or erode public trust. By closely studying the Municipal EA process for Riverside Dam, this thesis examines how values, trade-offs, and potential designs are communicated through visualizations and contested. Drawing from literature on landscape architecture visualization studies, Indigenous knowledge systems, and environmental design, the thesis proposes a framework for negotiated design to better support engagement with the community. Negotiated design in this thesis is an approach to environmental planning and restoration that prioritizes structured dialogue and collaboration among diverse stakeholders with often competing interests. This framework is a call for transparency, accessibility, and legibility in architectural drawings in so that the public is aware of what is at stake with each “preferred alternative” within the Environmental Assessment process. Within the proposed framework, this thesis lays out four visualization principles including: 1) contextual clarity, 2) embodied perspectives, 3) temporal layering, and 4) making conflict visible. Engagement principles also emphasize the use of physical space, co-creation, and writeable, decision-oriented drawings. Rather than producing an original design proposal, this thesis reinterprets three existing shortlisted design options (or “preferred alternatives”) for the Riverside dam: rebuilding, removing and naturalizing, and building an offline dam and naturalizing the river. Through different forms of visualization, the framework developed in the thesis are applied to visualize trade-offs, reveal biases, and imagine the realities of each design to best engage and educate the public. These River drawings are not final answers but rather invitations for further negotiation. By centering legibility over resolution, this work positions visualizing ecological projects as a collaborative and evolving act. It contributes to broader conversations on climate resilience and adaptation, decolonial landscape practice, and the role of design in environmental governance.
Beyond the Reason-Emotion Divide: Philosophical Theories of Autonomy from a Neuroscience Perspective
(University of Waterloo, 2026-01-14) Drecun, Darlene
This dissertation explores how recent neuroscience research might bear on philosophical theories of personal autonomy, with a special focus on the work of Christine Korsgaard and Harry Frankfurt. A central question within the personal autonomy literature is what gives our actions self-governing authority? Many approaches have answered this question with requirements about how we ought to reason or feel about our desires. One prominent way of dealing with this question of authority is a requirement of reason being “in control” of our emotions, presenting the relationship between reason and emotion as competitive processes fighting for control over our decisions. However, by examining recent neuroscience research related to the concept of autonomy, I argue that this research paints a different picture, where reason and emotion function cooperatively rather than antagonistically. Furthermore, the research suggests a prominent role for emotion in many different autonomy-related processes. In order to widely capture the many processes that underlie autonomy, I discuss the neuroscience of decision-making, self-control, voluntary action, and the conscious feelings related to agency and ownership over our actions. I examine some of the emerging trends in cognitive neuroscience that suggests that complex behaviours like decision-making and self-control emerge from large-scale neural networks located across widely distributed areas of the brain, where cognitive, emotional, and motivational information are deeply integrated at the neural level. I argue that this new notion of cognitive, emotional and motivational information as integrated in various processes, such as decision-making and control, has a direct impact on the concept of personal autonomy. First, this integration suggests that cognitive, emotional and motivational information all cooperatively contribute to autonomy processes, rather than competing. Second, the research suggests a larger role for emotion and motivation in processes like decision-making and self-control than is commonly assumed in philosophical theories of autonomy. Therefore, I argue that this integrated neuroscientific perspective highlights some important tensions between the neuroscience research on autonomy processes and philosophical theories of personal autonomy, like those of Korsgaard and Frankfurt. I examine the possible implications that the neuroscience of decision-making, self-control, voluntary action, and conscious feelings of agency may have on the autonomy theories of Korsgaard and Frankfurt. I point out several key tensions between the neuroscience research and how these theories of autonomy understand desires as motivating our actions, the role of emotion in decision-making and self-control, and whether we ought to rely on our conscious feelings of agency and control over our actions when determining whether our actions are autonomous. I suggest overall that an integrated neuroscientific understanding of the processes that support autonomy-related behaviours can provide a novel approach to understanding the concept of personal autonomy.
Learning to Reach Goals from Suboptimal Demonstrations via World Models
(University of Waterloo, 2026-01-14) Ali, Qasim
A central challenge for training autonomous agents is the scarcity of high-quality and long-horizon demonstrations. Unlike fields such as natural language or computer vision—where abundant internet data exists—many robotics and decision-making domains lack large, diverse, and high-quality datasets. One underutilized resource is leveraging suboptimal demonstrations, which are easier to collect and potentially more abundant. This limitation is particularly pronounced in goal-conditioned reinforcement learning (GCRL), where agents must learn to reach diverse goal states from limited demonstrations. While methods such as contrastive reinforcement learning (CRL) show promising scaling behavior when given access to abundant and high-quality training demonstrations, they struggle when demonstrations are suboptimal. In particular, when training demonstrations are short or exploratory, CRL struggles to generalize beyond the training demonstrations, and the resulting policy exhibits lower success rates. To overcome this, we explore the use of self-supervised representation learning to extract general-purpose representations from demonstrations. The intuition is that if an agent can first learn robust representations of environment dynamics—without relying on demonstration optimality—it can then use these representations to guide reinforcement learning more effectively. Such representations can serve as a bridge between noisy demonstrations and goal-directed control, allowing policies to learn faster. In this thesis, we propose World Model Contrastive Reinforcement Learning (WM-CRL), which augments CRL with representations from a world model (WM). The world model is trained to anticipate future state embeddings from past state–action pairs, thereby encoding the dynamics of the environment. As the world model aims to only learn environment dynamics, it can leverage both high and low quality demonstrations. By integrating these world model embeddings into CRL’s framework, it can help CRL more easily comprehend the environment dynamics and select actions that more effectively achieve its goals. We evaluate WM-CRL on tasks from the OGBench benchmark. We explore performance on multiple locomotion and manipulation environments and multiple datasets varying in quality. Our results show that WM-CRL can substantially improve performance over CRL in suboptimal-data settings, such as stitching short trajectories or learning from exploratory behavior. However, we find our method offers limited benefit when abundant expert demonstrations are available. Ablation studies further reveal that success depends critically on the stability of world model training and on how its embeddings are integrated into the agent’s architecture.
Sanctuaries of the Heart: Perception, Phenomenology and the Architecture of Salutogenic Healing
(University of Waterloo, 2026-01-13) Ahsan, Rabbiya
The thesis investigates the role of architecture as an active agent of healing by redefining salutogenic design through the lens of spatial phenomenology. It draws from the author’s own lived experience with mood disorders as well as extensive interdisciplinary research. The paper critiques historic, as well as modern healthcare approaches and treatment methods for mental health, with case studies such as Bethlem Royal Hospital and more sterile hospitals of today. In contrast, it studies the ancient healing methods that integrate the mind, body and spirit through spatial symbolism and rituals. Additionally, the project incorporates Maggie Keswick Jencks’ diaries through the lens of Critical Discourse Analysis, to understand a patient’s perspective when they navigate healthcare facilities. The thesis further studies the impact of the diaries in the form of a detailed case study of the Maggie Centre. Other case studies also contribute to understanding nature, materiality and sensory experience which combine under the umbrella term of spatial phenomenology and often nurtures positive recovery. Central to this research is salutogenesis, an idea that can be reframed to fit in the architectural narrative. This results in a proposed design of a mental wellness facility, located on the banks of the Grand River, a site with rich history and ecological vitality. The design serves as a manifesto for salutogenic design, choreographing light, sound, scent, texture and time, it dissolves the Cartesian split between mind and body and creates a space which contributes actively in the healing process.

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