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Data-efficient deep learning for predictive modelling of conventional single slope solar stills : leveraging transfer learning and tailored data augmentation strategies
No full textConventional single-slope solar stills are essential for decentralized freshwater production, yet their performance optimization is limited by small datasets and the nonlinear dynamics of desalination. This doctoral thesis addresses these constraints by developing and evaluating data-efficient supervised machine learning frameworks to predict freshwater productivity (Pstd, L/m²·day). The study integrates a novel high-performance solar still design with two complementary learning paradigms: Transfer Learning (TL) and tailored Data Augmentation (DA).
The research begins with the design and MATLAB/SIMULINK simulation of a photovoltaic-assisted single-slope solar still engineered for improved thermal performance. The hybrid system achieved a peak efficiency of 45%, and its 730-sample dataset served as the “source” domain for TL.
The first paradigm introduces a cross-design TL framework. A source Artificial Neural Network (ANN) was pre-trained on the hybrid system simulation data, and its learned weights were transferred and fine-tuned to model a conventional solar still using only 365 experimental samples. The optimized TL-based ANN (5-64-64-1) outperformed both randomly initialized ANNs and Multiple Linear Regression (MLR), achieving an Overall Index of Model Performance (OIMP) of 0.872 and demonstrating superior predictive accuracy and generalization.
The second paradigm develops a tailored DA strategy to directly expand the conventional still’s limited dataset. Gaussian noise–based jittering was applied to sequential inputs within a 7-day look-back window to generate synthetic training data for a one-dimensional Convolutional Neural Network (CNN-1D). The optimized CNN-1D model—comprising three 128-filter convolutional layers—substantially outperformed baseline CNN and Support Vector Regression (SVR) models, achieving an RMSE of 0.045 and an OIMP of approximately 0.97. A threshold-based classification method was also introduced to translate raw predictions into interpretable productivity categories.
Overall, this thesis provides a comparative evaluation of TL and DA approaches, validating their effectiveness in addressing data scarcity in solar still modeling. Key contributions include a novel cross-design TL framework, a specialized DA technique for time-series solar still data, and highly accurate predictive models. The findings provide practical, cost-effective tools for optimizing conventional solar stills and underscore the broader potential of advanced machine learning in renewable energy–driven desalination.Applied Science, Faculty ofChemical and Biological Engineering, Department ofGraduat
Deciphering the ductile deformation mechanics and piezometric stress record of metamorphic crust
No full textMetamorphism is intrinsically linked to the long-term strength of middle to lower crust, which in
turn controls the extent and distribution of regional deformation. Our collective understanding of
the strength of metamorphic rocks, namely the rheological behavior and deformation
mechanisms of individual minerals, relies upon decades of carefully controlled rock deformation
experiments. As these experiments are conducted over short time frames and often with either
single phase or previously equilibrated multi-phase aggregates, by design they typically do not
capture the chemical processes (i.e. metamorphism) that operate in the lithosphere over million
year timescales. To better understand how the interaction between metamorphism and ductile
deformation affects the strength of the mid- to lower crust, we need to: (1) compare mineral
microstructures from deformation in both natural and experimental settings to unravel how the
deformation mechanisms of metamorphic minerals evolve alongside metamorphic processes; and
(2) obtain empirical measurements directly from metamorphic minerals to estimate the bulk
stresses within a polymineralic crust.
In this thesis, I investigated how subgrain-size piezometry can be applied to the mineral
assemblages of metamorphic rocks from a range of geodynamic environments to better
understand the interplay of metamorphism and mineral deformation. In each chapter I apply a
range of characterization techniques to document mineral chemistry and microstructures, and on
the basis of these data infer the deformation mechanisms responsible for their formation. Using a
subset of amphibole-bearing rocks from a subduction zone setting, I demonstrate how the higher
inherent effective diffusivity and greater abundance of chemical reactions within polymineralic
rocks may impact the active deformation mechanisms. I also demonstrate how stress estimates
from subgrain-size piezometry can be coupled with thermodynamic modelling and single-mineral thermometry to infer the stress that rocks underwent at specific portions of their metamorphic histories. I find that the stress estimates derived from multiple mineral phases in a single rock are most consistent with isostress conditions in shear zones, wherein the bulk strength of ductile crust is defined by the strength of the weakest interconnected phase. My thesis and the approaches documented herein serves as a guide for petrologists to accurately attribute subgrain-size piezometric stress estimates to metamorphic conditions as well as for researchers to test theoretical models of the strength of the metamorphic crust using polymineralic rocks deformed in shear zones.Science, Irving K. Barber Faculty of (Okanagan)Earth and Environmental Sciences, Department of (Okanagan)”Graduat
Stress and coping among sport psychology consultants
No full textThe study of coach and athlete wellbeing has been a focal point in recent sport psychology research, in part, as a response to the recognition that participation in sport can potentially lead to detrimental psychological outcomes. A proposed way to help abate negative outcomes in sport has been to introduce more sport psychology consultants (SPCs) into these contexts to promote optimal performance and wellbeing. However, there is limited evidence pertaining to the perspectives of practicing SPCs and their experiences with stress and coping. Framed by cognitive motivational relational theory, the aim of this study was to explore SPCs’ experiences with stress (i.e., identify key stressors that SPCs face and how they tend to cope with these stressors). Eleven SPCs practicing in Canada shared their experiences at two time-points via semi-structured, one-to-one interviews. The first interview involved building rapport with participants before exploring their personal and professional journey in becoming a SPC. Discussions around their experiences with stress along that journey were embedded throughout that interview. The second interview involved a more specific investigation of SPCs’ experiences with stress and coping. The discussions in this interview were guided by the cognitive motivational relational theory. Using reflexive thematic analysis with abductive coding, three themes were constructed from the qualitative dataset. Anchored by a Passion for Helping in Sport related to the development of SPCs’ desire to help others in sport and how this passion shaped, and continues to shape, their experiences with stress. Navigating the Currents of (Shifting) Sociocultural Tides pertained to SPCs’ perceptions of stress working in contexts rife with nescience relating to their work, conflicting expectations from others, and tensions between efforts to enact ‘safe sport’ versus more ‘old school’ (i.e., performance-focused) priorities. Finally, Seeking Elusive Stability in Choppy Waters outlined experiences of stress as a function of working within the incessant job- and financial-insecure SPC job landscape in Canada. Insights regarding experiences of stress and coping among SPCs help shed light on the sparsely researched perspectives of SPCs working in Canada, thus responding to calls for progressing evidence-based knowledge on the perspectives of other non-athlete/coach participants in sport.Education, Faculty ofKinesiology, School ofGraduat
Neuromodulation for opioid use disorder in Canada : risks, benefits, values, and justice
No full textDespite increased efforts to intervene via harm reduction, educational initiatives, and treatment, the overdose crisis continues to be a significant crisis in Canada. Neurotechnologies such as deep brain stimulation, focused ultrasound, and repetitive transcranial magnetic stimulation have gained traction as possible treatments for substance use disorders and shown promising preliminary results. However, neurotechnologies have been met with apprehension owing to fear, stigma, and reluctance to label addiction as a brain disorder. Further complicating this issue are sociocultural factors as marginalized communities are disproportionately burdened by opioid use disorder (OUD) while having unmet needs and a history of distrust in the health system. Taking a living ethics stance, this dissertation sought to examine the ethics of using neurotechnologies for OUD in Canada.
Living ethics is a stance in empirical ethics which emphasizes ethical issues as lived and embodied by individuals and centers epistemic justice by advocating for collaboration with diverse interest-holders in moral deliberations of ethics research. This dissertation argues for the application of a living ethics stance in substance use bioethics research, outlining the key role people who use drugs (PWUD) can play in identifying and addressing ethical issues in substance use treatment.
Using a living ethics stance, the empirical work of this dissertation included semi-structured interviews with PWUD (N=22) in Vancouver, BC. Data were analyzed using a narrative ethics approach to capture a holistic view of patient perspectives. Participants reported that foundational elements of their lives must be addressed alongside the development of novel treatments. This included fulfillment of basic health and social needs, as well as discrimination- and stigma-free health care that respects their autonomy. Surrounding neurotechnologies specifically, participants had concerns about the invasiveness, the inaccessibility of treatment protocols, the potential for further dehumanization of PWUD, and the experimental nature of neurotechnology. Despite these concerns, the majority favoured continued development, and many indicated interest in using neurotechnologies.
This dissertation concludes with a discussion of practical implications and proposed recommendations to ensure neurotechnologies are developed to be accessible and equitable, and delivered in a stigma- and discrimination-free context where the basic needs of PWUD are fulfilled and patient autonomy is honoured.Medicine, Faculty ofMedicine, Department ofGraduat
Unfamiliar kin : queer alliance and textual kinship in twentieth-century women's writing
No full textIn this dissertation, I situate my study in the writings of American and British women in the twentieth century, arguing that, in the development and aftermaths of the stylistic and print practices of transatlantic literary modernisms, one can trace the development of a queer feminist identity and lineage. I base my work on critical excavations of queer modernisms that have occurred over the last thirty years and, specifically, recent re-evaluations of earlier, more circumscribed treatments on the intertwined developments of modernist stylistics and non-normative identity. Moving from this, I use a series of case studies to sketch both the influence of sapphic writing on the development of modernism and the ways in which sapphic modernism, in its stylistic markers, its histories and figures, and its harnessing of specific print and publishing tactics, served as a constructing influence on later-century formations of identity and community. The case studies I employ are deeply personal and individuated: They reflect the specific desires and impulses of their originators and, thus, speak to situated perspectives within a particular time and place. However, each case depends upon a dedication to stylistic homage and thematic citation, a practice in which the high stakes of intergenerational connection and conversation are always at play. Though effectively expanding and exceeding the twentieth century, the tactics and motivations that bring together such temporally, generically diverse authors as Michael Field (Katherine Bradley and Edith Cooper), Renée Vivien, H.D., Nella Larsen, Danzy Senna, Djuna Barnes, and Bertha Harris are strikingly similar. Together, they paint a convincing portrait of both the utopian promise—and the more realistic vagaries—of a coherent, transatlantic, queer literary kinship between women writers in the twentieth century.Arts, Faculty ofEnglish Language and Literatures, Department ofGraduat
Detection and reporting of spectrum misbehaviour in connected vehicle networks
No full textConnected Vehicle (CV) networks facilitate wireless data exchange between vehicles, infrastructure, and other devices (V2X). A reliable and clear wireless medium is required for the implementation of a CV network especially for safety-related applications. CV networks based on DSRC, ETSI ITS-G5 and C-V2X technologies are susceptible to interference and congestion from both non-CV devices that may be authorized to share the same band and unintentional emitters.
Currently, there is no mechanism to detect such interference and congestion which may lead to unreliable communication. Thus, in this research we introduce the need, identify the options, provide a practical scalable architecture for large-scale interference and congestion monitoring system in CV networks, and deploy and validate a proof-of-concept (PoC) demonstration. The architecture comprises three layers: detection, reporting, and central authority.
For the detection layer, we developed three IEEE-based models using the IEEE 802.11p Physical Layer Convergence Procedure (PLCP) and Physical Medium Dependent (PMD) state machines, and one C-V2X model based on Sensing-Based Semi-Persistent Scheduling (SB-SPS).
For the reporting layer, we adapt the IEEE 1609 Security Credential Management System (SCMS), originally developed for DSRC, to enable secure reporting of spectrum misbehaviour. Devices (RSUs or OBUs) detecting an event can generate a Spectrum Misbehaviour Report (MBR). If sufficient evidence is collected, the report is forwarded through SCMS to a Spectrum Misbehaviour Authority.
For the central authority, we designed and validated a reference Spectrum Misbehaviour Authority (SMA) capable of interference source localization. Our approach combines state-of-the-art localization algorithms with unsupervised learning techniques, eliminating the need for prior knowledge of interference sources.
In summary, we have proposed detection of spectrum misbehaviour at the device level, reporting of spectrum misbehaviour via an already implemented system with minor modifications, and analyzing of the spectrum misbehaviour reports in a central unit. We have validated the feasibility of the detection mechanism in the lab environment as well as in real-world environment. We have defined a detailed architecture of the SMA and its components including database, data validation and authentication unit, data processing unit structure, and others. We finalized the design and implemented the operational PoC at the AURORA connected vehicle testbed.Applied Science, Faculty ofElectrical and Computer Engineering, Department ofGraduat
From understanding to repair : an empirical and agentic investigation of Ruby developer challenges
No full textThis thesis investigates the challenges faced by Ruby developers and proposes an automated, language-specific solution to one of their most critical problems which is program repair. The research is conducted in two phases. In Phase One (Unveiling Ruby), we examine the landscape of Ruby development by analyzing 498,719 Ruby-related questions from Stack Overflow and validating the findings through a survey of 154 developers. Using BERTopic for topic modeling, GPT-4o for taxonomy construction, and human validation, we identify a three-level hierarchy of 35 topics, 18 middle categories, and six main categories of Ruby challenges. The results reveal that web application development, application quality and security, and data management are the most discussed areas, while debugging and repair are perceived as the most time-consuming tasks. The study also exposes discrepancies between objective platform metrics and developers’ perceived difficulty, emphasizing the need for better evaluation methods and more supportive tools for Ruby practitioners. In Phase Two (RAMP: Ruby Automated Multi-Agent Program Repair), we introduce a lightweight, feedback-driven framework for Automated Program Repair that uses large language models in a multi-agent setup. RAMP distributes the repair process among specialized agents: Programmer, Test Designer, Test Executor, and Feedback Integrator, who collaborate iteratively through test-guided reflection. Evaluated on the Ruby subset of the XCodeEval benchmark, RAMP achieves a pass@1 accuracy of 67.0%, outperforming baselines such as LANTERN, ChatRepair, Self-Planning, and Self-Collaboration, while remaining resource-efficient. Together, these two phases bridge empirical understanding and intelligent automation. The findings provide the first comprehensive characterization of Ruby developer challenges and demonstrate the feasibility of lightweight, feedback-driven repair systems for underexplored languages. This work contributes to both empirical software engineering and LLM-based program repair by emphasizing data-driven, and resource-aware approaches to improving developer productivity.Science, Irving K. Barber Faculty of (Okanagan)Computer Science, Mathematics, Physics and Statistics, Department of (Okanagan)Graduat
Effectiveness of an interactive preventative dental program for elementary school-aged children
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Dentistry, Faculty ofGraduat
Flow liquefaction and mobile landslides triggered under static conditions : insights from case studies on tailings dams, earth dams, and glacial slopes
No full textThe full abstract for this thesis is available in the body of the thesis, and will be available when the embargo expires.Applied Science, Faculty ofEngineering, School of (Okanagan)Graduat
Beyond the music : an embodiment-based approach to song recital preparation—integrating, eurhythmics, laban, and bmc®
No full textNon-verbal communication elements influence our understanding of audio-visual information. Evidence suggests that when gestures and sound are congruent, emotional intent is more clearly understood. In a song recital, performers convey a song’s emotional content through non-verbal elements, such as gestures, bodily movements, and facial expressions.
While vocal recitalists are often heavily trained to develop skills in areas such as vocal technique, poetic analysis, historical context, thoughtful program design, and language mastery, movement skills for the physical dimensions of storytelling are often under-emphasized.
Despite growing evidence of visual primacy, few song recital rehearsal techniques address the need for structured physical training. Recitalists have limited resources for effective practice techniques that address body movement in recital. This project expands the practice guidelines from Emmons and Sonntag’s book, The Art of the Song Recital, by integrating Dalcroze Eurhythmics, Laban Efforts, and Body-Mind Centering®, providing application analysis to more fully support the foundational aspects of song recital: vocal pedagogy, poetic text engagement, and the often-overlooked role of the body in singer-pianist collaborative techniques.
The result is a practical resource for rehearsal, a Practice Companion, that helps performers translate artistic vision into embodied expression through the coordinated integration of mind, body, voice, and music. The Practice Companion presents exploratory rehearsal exercises for solo singers and collaborative duos that draw from three approaches: Eurhythmics fosters musicality, coordination, and the embodiment of rhythm; Laban enhances the conscious articulation of movement; and BMC® encourages awareness of how the mind expresses itself through the body. The Practice Companion aims to improve the audience’s perception of the artist’s emotional and expressive intent.
This project contributes to the ongoing revitalization of the song recital by encouraging creativity, expressive delivery, and interpretive risk-taking. It offers a curriculum-ready resource for vocal performance and singer–pianist training, presenting a fresh approach to recital preparation grounded in embodied practice.
The Introduction establishes the conceptual foundation, presents scientific evidence, and reviews relevant literature. Part I (Chapters 1–3) introduces each movement method and its exercises. Part II (Chapters 4–5) presents outcomes, rehearsal reflections, a case study, and concluding insights.Arts, Faculty ofMusic, School ofGraduat