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Item type: Item , Access status: Embargo , Toward Efficient Thermal Management of High-Heat Flux Power Conversion Units Using a Topology-Optimized Heat Sink: Numerical and Experimental Analyses(2026-04-30) Mazaheri, Nima; Mwesigye, Aggrey; Mohamad, Abdulmajeed; Hinman, Schuyler; Hugo, Ronald; Rowe, AndrewEffective thermal management plays a critical role in improving power density, energy conversion efficiency, and operational reliability of electrified powertrains subjected to high heat flux conditions. This thesis explores advanced thermal management strategies for high heat flux electronics cooling, with a particular focus on cooling power conversion units embedded in motor inverters of electric and hybrid vehicles. The novelty of this thesis lies in the development and integration of topology-optimized heat sink designs, including double-layer micro-jet heat sink (DLMJHS) and pin fin heat sinks aimed at simultaneously maximizing heat transfer performance and minimizing pumping power. Moreover, the potential of engineered working fluids, particularly supercritical carbon dioxide (sCO2) in enhancing the hydrothermal efficiency of the cooling system was also examined. A combined numerical and experimental methodology was adopted to assess the hydrothermal performance of these cooling approaches under high heat fluxes up to 360 W/cm2. For the numerical simulations, a finite volume technique was implemented using ANSYS Fluent software with second-order upwind discretization scheme and Semi-Implicit Pressure-Velocity (SIMPLE) coupling algorithm. The gradient-based adjoint technique was employed to conduct multi-objective shape optimization, enabling the identification of innovative pin fin designs with enhanced heat transfer capability and reduced pumping power. The optimized configurations were systematically compared with baseline geometries in terms of convective heat transfer coefficient, thermal resistance, temperature uniformity, pressure drop, pumping power, and overall energy efficiency. The outcomes reveal remarkable performance improvements across the proposed designs. The optimized DLMJHS achieved a peak heat transfer coefficient of 80.5 kW/m²·K and a 7.44℃ reduction in the baseplate temperature. When running by sCO₂, the DLMJHS delivered a global heat transfer coefficient of 60.4 kW/m²·K and provided 5 times better temperature uniformity compared to water. For 12 pairs of IGBTs and diodes, the topology-optimized pin fin configurations achieved up to 29% enhancement in heat transfer performance and reduced pumping power by up to 34%, with temperature reductions of 8.1°C at the baseplate level. The experimental setup was designed and developed to test the best optimized pin fin heat sink configuration and validate the numerically obtained results. To simulate the high heat flux of the motor inverter rated 120 kW, six 600 W heaters (each giving 200 W/cm2 over a 3 cm2 footprint), with a total thermal load of 3.6 kW, were used. The heaters were placed underneath the cold plate at specific distances according to the drive inverter of the Toyota Prius. A 5 kW three-phase power supply is used to supply the required electrical energy. The optimized cold plate showed up to 66% improvement in heat transfer capability, 19% reduction in thermal resistance, and 15% lower pumping power compared to conventional designs. The developed cold plate achieved a peak heat transfer coefficient of 18 kW/m²·°C, reduced average module temperature by up to 14.5°C, and improved temperature uniformity by 54%. With a mass of 0.902 kg and a power density of 133 kW/kg, the proposed design provides a compact, high-performance cooling solution for electrified powertrains.Item type: Item , Access status: Open Access , Transferring Knowledge to Practice: Innovative Pedagogy for Multicultural Counselling(2015) Arthur, Nancy; Cui, Dan; Gust, LisaWith increased sensitivity to multicultural counselling in the past few decades there has been greater need to prepare professionals who can work across cultures and develop multicultural competence. In turn there has been a need for resources to inform the teaching and learning in this field and determine ways consistent with inquiry-based and experiential learning to impart this knowledge to future practitioners and increase cognisance and application of theory to matters of self-awareness, better multicultural understanding and social justice to come up with a culture-infused counselling model.Item type: Item , Access status: Open Access , Uptake of Peer and Instructor Feedback in an Online Graduate Course: Learning and Instructional Implications(2017) Chu, Man-Wai; Crossman, Katherine; Dressler, Roswita; Hilman, BriannaEmbedded formative feedback on drafts of student writing from peers and instructor has been found to improve overall quality of performance (Sambell, 2011), encourages students to begin their writing earlier and substantially revise their drafts (Baker, 2016). Students often receive such feedback and corrections within their writing with mixed emotions, especially when comments are harsh. As a result, they sometimes reject corrections or suggestions for improvement (Mahfoodh, 2017). The Learning Error and Formative Feedback (LEAFF) model is a conceptual tool for understanding embedded formative feedback which hypothesizes students are more receptive to feedback when it comes with an emotionally safe environment. (Leighton, Chu, & Seitz, 2013). This research sheds light on the importance of examining not only the giving of feedback but its use and uptake.Item type: Item , Access status: Open Access , Evaluating the Barriers and Facilitators of Current ESAS-r Use in an Oncology Practice Setting Through the CFIR Framework to Support the Future Implementation of ESAS-r-Cancer.(2026-05-08) Larmet, John Andrew; Laing, Catherine; Lambert, Leah; Watson, Linda; Vogelsang, Laura; Kawalilak, ColleenIn this study, I examined the multi-level barriers and facilitators influencing the current integration of the Edmonton Symptom Assessment System-revised (ESAS-r) in both new and recurring patient appointments. The ESAS-r is a validated tool for the systematic evaluation of symptoms in oncology patients (Watson et al., 2023). Despite its recognized benefits, longitudinal and consistent integration into daily clinical practice at BC Cancer has been lacking. Using the Consolidated Framework for Implementation Research (CFIR) as a guide, qualitative and quantitative data were collected from oncologists and nurses to explore the reasons behind the poor adoption of current evidence-based practices with respect to ESAS-r utilization within all comprehensive cancer centers in British Columbia (BC). The CFIR domains consist of intervention characteristics, inner and outer settings, characteristics of individuals, and processes. Specifically, the focus of this study was to identify the barriers and facilitators by analyzing the inner setting (i.e., structural characteristics, relational connections, communications, culture, and implementation climate and readiness) and the outer setting (i.e., local attitudes of patients’ need, local conditions [cosmopolitanism/peer pressure], external policies, and laws; Damschroder et al., 2022). The study did not examine CFIR domains related to intervention characteristics, characteristics of individuals, or implementation processes, as these constructs were beyond the defined scope of this inquiry, however the characteristics of individuals are highlighted as the evidence produced exhibited important findings that support the clinical context in which the ESAS-r is used within BC Cancer. Through the identification of multi-level barriers and facilitators guided by the CFIR (inner and outer domains), several key factors influencing the use of the ESAS-r within BC Cancer were identified. These findings enabled the development of targeted, evidence-informed strategies to support a standardized and efficient implementation process, thereby enhancing organizational readiness for the routine use of the ESAS-r-Cancer (Watson et al., 2024). This research contributes to the broader field of implementation science by offering a context-specific, yet potentially transferable, model for embedding clinical assessment tools within complex healthcare systems. By adopting a multifactorial implementation approach, actionable strategies guided by the Expert Recommendations for Implementing Change (ERIC) framework (Powell et al., 2015; Waltz et al., 2015) were identified to support the sustained integration of the ESAS-r into standard oncology care at the system and organizational level.Item type: Item , Access status: Open Access , Creating a Playful Culture of Learning with Gameful Assessment: Avatars, Experience Points and Boss Battles in a Graduate Course(2016) Bastani, Reyhaneh; Clyde, Jerremie; Gupta, Diali; Kim, BeaumieThe NMC Horizon Report: 2014 Higher Education Edition highlights how games and gamification as digital strategies transcend conventional learning activities and are likely to drive future technology-related decision-making in higher education (Johnson, Adams Becker, Estrada, & Freeman, 2014). Some higher education instructors indeed attempted to incorporate principles of games into the course activities and assessments, calling their effort “educational gamification”. The concerns arise with the focus on competitive nature of scoring points, and the associated connotation of tricking learners, or sugar-coating learning, when the learning itself should be engaging. We also recognize this concern and value the skills (e.g., risk-taking, persistence, problem-solving) required when playing games. To shift our scholarly and design focus from the mechanics of game-like designs to the learning experience, we adopted the notion of “gamefulness” (MacGonigal, 2011; Holden et al., 2014). Our goal was to explore the design of gameful activities and assessment, and how such designs create a culture of learning in the graduate education context.
