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Urban disruption of the land-sea connection : understanding stormwater and river inputs from Metro Vancouver and particulate organic matter composition in Burrard Inlet British Columbia
No full textUrbanization has disrupted the movement of freshwater and the materials it transports, altering the primary biogeochemical link between land and sea. Coastal ecosystems are subsidized by terrestrial organic matter and nutrient inputs; however, inputs have increased or been altered due to land-use change. Urbanization has increased impervious surfaces, changed vegetation abundance and composition, and introduced novel inputs via wastewater and stormwater. To investigate freshwater and stormwater organic matter and macronutrients (silicate, phosphate, and nitrate), I compared these constituents in Metro Vancouver river water and stormwater to literature values. I estimated the flux of these biogeochemical parameters transported to Burrard Inlet via stormwater annually and identified tracers of stormwater using stable isotopes (carbon and nitrogen) and fatty acids. The concentrations of these biogeochemical parameters were high and generally significantly different between river and stormwater samples. There were higher concentrations of nitrate and silicate in river samples and higher concentrations of phosphate, dissolved organic carbon, particulate organic carbon, and particulate nitrogen in stormwater samples. To investigate the composition of particulate organic matter (POM) in the surface water of Burrard Inlet, I used a Bayesian mixing model approach (MixSIAR) to quantify the relative contributions of phytoplankton, macrophyte, freshwater, and wastewater across 5 basins and 3 seasons. POM is a basal resource for marine food webs and a key component of zooplankton diet, which transfers energy to higher trophic level organisms. Thus, understanding how urbanization changes the composition of POM is important for understanding the productivity and functioning of marine ecosystems. Across all basins and seasons, phytoplankton contributed the most (average = 80 %), followed by macrophytes (average = 7.9 %), wastewater (average = 6.1 %), and freshwater (average = 5.8 %). There were seasonal and spatial differences in POM composition. As cities expand, so will their impact on coastal marine environments, and therefore, there is a need to understand how urbanization changes freshwater and the materials it transports, disrupting marine productivity and ecosystem functioning.Science, Faculty ofOceans and Fisheries, Institute for theGraduat
Viability estimation for diffusion-based planning
No full textDiffusion models can be used as a motion planner by sampling from a distribution of possible futures. However, the samples may not satisfy hard constraints that exist only implicitly in the training data, e.g., avoiding falls or not colliding with a wall. We propose learned viability filters that efficiently predict the future success of any given plan, i.e., diffusion sample, and thereby enforcing an implicit future-success constraint that favours plans likely to succeed in the future. These filters identify samples from the output of a diffusion-based motion planner with respect to implicit constraints and take the general form of a learned Q-function. This allows for efficient online planning with diffusion models, including for situations where the diffusion model and viability filter have different access to environment observations. Multiple viability filters can also be composed together so that they are each taken into consideration. We demonstrate the approach on detailed footstep planning for challenging 3D human locomotion tasks, showing the effectiveness of viability filters in performing online planning and control for box-climbing, step-over walls, and obstacle avoidance. We further show that using viability filters is significantly faster than guidance-based diffusion prediction.Science, Faculty ofComputer Science, Department ofGraduat
Building an artificial-intelligence powered metaphor-based visualizer for human self-understanding
No full textThis thesis explores the design and development of Indra’s Net, an Artificial Intelligence (AI) powered metaphor-based visualizer that aims to enhance human self-understanding through dynamic and interactive visual metaphors. The platform translates abstract psychological states and processes such as withdrawal, arousal, openness etc. into immersive visualizations, using the universal metaphor of light. Built on Unreal Engine 5, Indra’s Net combines visual technologies, such as dynamic lighting, advanced material rendering, and particle systems, with AI-driven interactivity to create a novel tool for introspection and emotional regulation.
The development process involved iterative prototyping to establish a framework where psychological concepts are systematically mapped to optical phenomena. Key technical innovations include the creation of a dual-surface spherical vessel in Blender, capable of depicting both internal and external cognitive interactions, and the integration of Unreal Engine 5’s particle systems and materials assets to enhance performance and realism. The platform’s modular architecture seamlessly connects an integrated Large Language Model (LLM) with the visualizer, enabling the AI assistant to interpret user inputs and dynamically update visualizations in real time. This conversational interaction supports intuitive onboarding and tailored user experiences.
Indra’s Net facilitates exploration of mental states and interpersonal dynamics, promoting self-reflection and creative insight through its metaphor-driven representations. The platform serves as both a standalone tool for personal growth and a potential resource for art therapy and mental health diagnostics. Future enhancements, such as biosensor integration, multi-user capabilities, and sonification, aim to provide a multisensory and collaborative experience.
By emphasizing both the technical implementation and the potential applications, this thesis demonstrates how Indra’s Net bridges abstract psychological concepts with potentially actionable visualizations. The project underscores the value of combining advanced visualization technologies and AI to create tools that inspire self-awareness, emotional regulation, and well-being.Arts and Social Sciences, Irving K. Barber Faculty of (Okanagan)Graduat
Revolution in imagery : visual representation of hegemony in Iranian illustrated books before and after the 1979 revolution
No full textThis thesis investigates the visual representation of ideological transformation in Iranian children’s picturebooks published by Kānoon-e Parvaresh-e Fekri-e Koodakān va Nojavānān, a state-funded cultural institution that operated under the authority of the ruling regime both before and after the 1979 Iranian Revolution. Focusing on a pivotal twenty-year period (1969–1989), the study explores how illustrations in these books reflect and construct cultural hegemony across two contrasting political systems: the secular nationalism of the Pahlavi monarchy and the religious ideology of the Islamic Republic.
Guided by Antonio Gramsci’s theory of cultural hegemony and employing Kathy Short’s model of critical content analysis, the research conducts a close visual and ideological reading of four focal Persian texts supplemented by the analysis of 36 additional illustrations drawn from Kānoon’s archive. The study is structured around three interrelated thematic inquiries: (1) how visual narratives articulate ideological and political messages, (2) how representations of cultural identity and heritage shift across regimes, and (3) how gender roles and social dynamics are visually constructed and communicated to young readers.
Findings reveal that illustrations in Kānoon books function as ideological artifacts, closely aligned with the dominant political discourses of their respective periods. During the Pahlavi era, visual narratives foregrounded Persian myth, pre-Islamic heritage, and national unity, often through grand historical or heroic imagery. In contrast, post-revolutionary publications exhibit a marked shift toward Islamic symbolism, revolutionary iconography, and visual codes reinforcing modesty, piety, and domesticity—particularly in the portrayal of female characters, who transition from unveiled and public to veiled and domestic figures.
By situating Iranian picturebooks within a broader framework of cultural production and state ideology, this study illuminates the ways in which visual storytelling serves as a subtle yet powerful vehicle of hegemonic transmission. It offers a rare English-language analysis of Iranian visual culture in children’s literature across a major sociopolitical rupture and contributes to the growing discourse on visual literacy, childhood education, and the politicization of cultural artifacts. Ultimately, it argues that picturebooks are not merely artistic or educational tools, but strategic instruments in shaping ideological consciousness in young audiences.Arts, Faculty ofInformation, School ofGraduat
Development of a high-performance hybrid steel-grout hold-down connection for mass timber panels
No full textThis dissertation explores the structural performance and predictive modeling of hybrid
steel-grout connectors for cross-laminated timber panels, addressing critical challenges in mass
construction. The hybrid connector consists of a thick layer of epoxy-based grout that surrounds
a steel rod. A comprehensive experimental investigation was conducted on key materials—
Canadian small clear spruce-pine-fir wood, epoxy-based grout, and steel rods—yielding
a robust dataset that informs the mechanical properties essential for connector design.
Advanced constitutive models were developed using continuum damage mechanics to capture
the unique behaviors of these materials under various loading conditions. Structural
performance evaluations through monotonic and cyclic testing revealed significant correlations
between connector geometry and loading direction, highlighting the influence of rod and grout diameters on strength and stiffness. Finite-element modeling provided insights into the mechanical behavior of connectors, enabling the prediction of performance parameters across multiple loading angles. An analytical model based on Beam on Elastic Foundation theory effectively correlated experimental results with theoretical predictions, emphasizing the critical role of grout properties in determining elastic stiffness. Furthermore, machine learning techniques were employed to predict secant stiffness and residual slip of hybrid connectors when subjected to cyclic loads, showcasing the power of deep neural networks in modeling complex interactions between material properties and performance metrics. The research culminates in the development of predictive equations that facilitate the design and optimization of hybrid connectors, ultimately contributing to the advancement of mass timber structures in sustainable construction practices.Forestry, Faculty ofGraduat
Mechanistic study of Suzuki-Miyaura cross-coupling reactions via real-time monitoring
No full textThe Suzuki-Miyaura reaction is currently the most practiced cross-coupling reaction due to its broad applicability, low toxicity of the boron, and the wide variety of commercially available boronic acid substrates. Given its widespread application across pharmaceutical, materials, and fine chemical industries, the mechanism by which the reaction occurs is of considerable interest.
Temporal profiling of chemical reactions provides the gold standard for increasing mechanistic understanding. However, acquiring reproducible and accurate time-course information while minimizing analyst intervention presents significant challenges.The integration of in situ analytical methods with automated sampling techniques offers a robust solution, enabling the acquisition of high-density, reliable temporal profiles for all observable species throughout a chemical transformation. These detailed reaction profiles reveal the dynamic signatures of underlying chemical processes, thereby informing process optimization and development.
This dissertation advances our mechanistic understanding of the Suzuki-Miyaura cross- couplings through real-time monitoring studies under two distinct conditions: widely employed biphasic conditions and novel homogeneous aprotic conditions utilizing potassium trimethylsilanolate (TMSOK) as base. By leveraging an automated reaction monitoring platform, we have enhanced the mechanistic understanding of each catalytic system, ultimately leading to more efficient transformations.Science, Faculty ofChemistry, Department ofGraduat
On Arrival : Rethinking Zoning and Land Use for Immigrant Communities
No full textOn Arrival reimagines zoning and urban design through the lens of immigrant experiences in Canada’s Arrival Cities. Rooted in personal memories of informal economies and multigenerational living in Surrey, BC, the project asks how built form can support the complex, adaptive ways newcomers live, work, and care for one another.
Focusing on a two-hectare parking lot adjacent to Guildford Mall, the proposal introduces low-rise, mixed-use typologies that blur residential, commercial, and light-industrial uses. Rather than meeting density targets through tower-podium morphologies, it explores a more intimate and socially responsive form of density, grounded in flexibility, affordability, and cultural context.
Through speculative design, On Arrival challenges the rigidity of North American zoning and reframes value not around real estate, but around the richness of daily life and community support.Applied Science, Faculty ofArchitecture and Landscape Architecture (SALA), School ofUnreviewedGraduat
Lost in transit : tracing Toronto’s ravine landscapes in the subway
No full textThe place between beginning and end - arrival and destination. Lost in Transit explores the in-between space of Toronto’s subway system. Challenging the standardization of the contemporary urban experience and the increasing disconnection between people and place. In designing for place, this graduate project connects the subway commuter to Toronto’s historical and present-day ravine landscapes. As the commuter follows the traces of the ravines within the subway, a hidden landscape of sewered creeks and seepage emerges. This project explores how we can better create landscape literacy and care in today’s urban condition of sameness, and further proposes that to create novel spaces, we must look at landscapes in novel ways.Applied Science, Faculty ofArchitecture and Landscape Architecture (SALA), School ofUnreviewedGraduat
Beauty and the heat : exploring transit user thermal perception beyond the surface
No full textIncreased urban heat, a dynamic and multi-scalar process, leads to thermal discomfort and health risks for urban residents. Public transit is essential in cities, offering mobility and reducing congestion, especially benefiting those vulnerable to urban heat. However, as urban heating intensifies, cities must adopt effective strategies to design thermally comfortable transit stops. Chapter Two explores thermal perceptions among transit users in Denver, Colorado, a semi-arid city, focusing on 60 bus stops with varying land cover. Surveys gathered users’ thermal perceptions and aesthetic preferences while micrometeorological data were recorded. Results show that thermal perceptions are significantly influenced by aesthetic preferences, which can even moderate thermal comfort perceptions in high-heat conditions. Bus stops with more large stature vegetation were perceived as more aesthetically pleasing, demonstrating the importance of aesthetics in transit design. Chapter Three compares hyper-local surface temperature (TS) measured via Forward-Looking Infrared (FLIR) imaging with Landsat 8 satellite-derived temperatures. Findings indicate that Landsat 8 measures TS 10.7 degrees Celsius higher on average than the FLIR, while FLIR offers finer-resolution data more closely aligned with thermal comfort indices like Mean Radiant Temperature (TMRT) and the Universal Thermal Climate Index (UTCI), explaining up to 68% of the variation in thermal comfort indices. This study encourages using simplified hyper-local methods, such as FLIR, to inform heat-resilient transit design. By integrating user perceptions, micrometeorology, and thermal imaging, this research provides valuable insights for urban planners aiming to mitigate urban heat and enhance thermal comfort in semi-arid cities.Forestry, Faculty ofGraduat
Kijikatig cedar carving narrative inquiry
No full textThis land- and art-based qualitative research investigates through in-depth personalized reflection narrative research, my lived experiences, process and perspectives about being an Indigenous carver, educator, and scholar. Specifically, it explores the role of wood carving during my studies at UBC in the NITEP, the Indigenous Teacher Education Program; a series of educational carving projects, and the unique Canadian Institute of Health Research (CIHR) KIJIKATIG project in the UBC graduate studies in the Faculty of Experimental Medicine. The CIHR KIJIKATIG art project included 20 Indigenous youth research participants. This reflexive research represents the storying of personalized reflections that address the need to create a wholistic, planetary health and well-being spaces to promote sustainable dialogues among Indigenous Knowledge, and the Western Science experts in the field of experimental medicine toward decolonizing education and pedagogy. This reflexive research draws upon the analysis of data gathered from my reflexive response to the core values of the Seven Grandfather Teachings, of Love, Respect, Bravery, Truth, Honesty, Humility, Wisdom and the principles of wholeness, symbiosis and simultaneity that align with carving project events. These reflexive research events are journeys expressed through the metaphoric KIJIKATIG (Cedar Tree) Education Model (KEM) that I designed to analyze this research. The methodology of capturing reflexive research reveals aspects of wholistic health and wellness through traditional land-and art-based teachings thereby highlighting best practices in education in the field of experimental medicine. The (KEM) has been used in two complementary ways within the research. First as a framework for data analysis and secondly as a conceptual metaphor for students. This research has at its core aspects of ‘wholeness and experience’ in narrative inquiry that works well with small groups. The KEM as a research model aligns the metaphor of the cedar tree and its growth stages the (1) pith, (2) heartwood, (3) sapwood, (4) cambium and (5) bark. The first four stages are personalized reflections highlighting the role my art and carving projects played in education and gaining of knowledge. While the fifth (bark) stage reflections represent the KIJIKATIG project whereby the carving session was recorded for transcription and knowledge was transformed.Medicine, Faculty ofMedicine, Department ofGraduat