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Kindah: Exploring Jamaica Caves as Cultural & Ecological Archives
Get PDFKindah, Exploring Jamaican Caves as Cultural and Ecological Archives, examines the distinctive spatial relationships the Maroons developed with the caves of Jamaica. Through analysis of Maroon oral histories and poetry, this research reveals the cultural memories surrounding caves as inscriptions of ecological knowledge, accumulated during their journey toward cultural emancipation. The forest, simultaneously a place of refuge and a site of sustenance. While caves perform as landmarks of pivotal stages in Maroon evolution. This study engages with the ways memory is embedded within geography, as a repository of ancestral knowledge and an active participant in freedom revolts. By tracing rhythms of displacement, ecological literacy, and spatial resistance, through pencil illustrations, collage, and poetic decoding, this analysis foregrounds the role of landscape in shaping narratives of Afro-Caribbean emancipation and self-determination
Design and Control of a Compact 7.2 kW GaN-Based Bidirectional Isolated On-Board Charger (OBC)
No full textThis thesis presents significant advancements in bidirectional onboard chargers (OBCs) for electric vehicles, addressing critical challenges in power factor correction, efficiency, and power density. The research introduces innovative control strategies and hardware designs by incorporating high power GaN switches that substantially improve OBC performance and compactness. The thesis introduces three major contributions: First, a novel Zero Crossing Voltage Control (ZCVC) strategy for Power Factor Correction (PFC) applications is developed. This approach ensures a consistent sinusoidal AC current, eliminates second harmonic distortions without notch filters, and achieves stability within 1.5 grid cycles during operational changes. The ZCVC method demonstrates a near-unity power factor, minimal Total Harmonic Distortion (THD), and reduced computational burden. Second, an innovative Zero Voltage quasi-Zero Current Switching (ZVqZCS) scheme is proposed for non-resonant isolated Dual Active Bridge (DAB) converters. This method achieves full Zero Voltage Switching and 75% quasi-Zero Current Switching across a wide range of input and output voltages while minimizing inverse power flow and significantly reducing di/dt in power loops. The proposed buck-boost ZVqZCS scheme is implemented in both charging and discharging modes, as well as constant-current (CC), constant-power (CP), and constant-voltage (CV) operations. Burst mode is introduced to further increase the range of full ZVS and 75% qZCS. Finally, the research presents remarkable hardware design improvements, achieving ultra-high power densities of 14kW/L for Totem-Pole PFC, 37 kW/L for DAB, and 10 kW/L for the overall OBC, representing 2X, 5X, and 3X improvements over latest reference designs from Texas Instruments, ST Microelectronics, and WolfSpeed, respectively. Peak efficiencies of 99% for interleaved PFC, 98.8% for DC-DC isolated DAB stage, and 97.8% for the overall OBC are demonstrated. These advancements significantly contribute to the development of more efficient, compact, and reliable OBCs using GaN technology supporting the ongoing transition to sustainable transportation
Movement ecology of brook trout and rainbow trout: Insights for watershed connectivity and hatchery practices
Get PDFManaging and conserving freshwater resources is becoming increasingly important given widespread habitat degradation and environmental change. As such, trout stocking is a common hatchery management tactic. I assessed the post-stocking fate of hatchery-reared Rainbow (Oncorhynchus mykiss; n = 15) and Brook trout (Salvelinus fontinalis; n = 12) released into small lakes (Kenauk, QC, CAN). Most tags showed probable mortality within one week of release. Trout post-release and pre-mortality behaviour suggested late-season stocking adaptability issues, likely driven by stress from high temperatures, predation, and handling. I also studied Brook trout (n = 60) stream connectivity within a Kinonge West River (Kenauk) reach to understand potential thermal and physical barriers, finding no movement river barriers and high trout site fidelity (with increased late fall/winter movement). These findings highlight the importance of hatchery management and temperature needs as well as protecting river connectivity to enable trout movement and biodiversity health
Investigating Graphical Realism in Mixed Reality and its Impact on Presence and Performance
Get PDFWe ran three studies focused on graphical realism and presence in Mixed Reality (MR) systems. The first study measured presence while we varied the ratio and the rendering style of virtual content. Results showed that the ratio did not impact presence, but rendering style did. They also noted that the elements of graphical realism important for VR systems may not be the same for MR systems. The second study attempted to use a rating system to quantify changes in graphical realism, creating a quality score. The results suggested that this system may be viable for this purpose. The third study attempted to examine how changing those quality scores impacts performance and presence at a high level. Results suggest that it may relate to performance if the graphical changes are specific to the task. They also suggest that current presence measurements may not be valid for MR
Aiming for Adaptation: Developing a Quantitative Framework for Building Resilience in Response to Climate Change-Induced Grid Outages
Get PDFClimate change intensifies the occurrence of extreme weather events, resulting in prolonged power outages and raising concerns about the resilience of buildings. This research addresses critical challenges in resilience development, including the lack of flexible definitions, cost-effective solutions, and financial evaluation metrics. A comprehensive framework was developed to assess building resilience through energy simulations, risk-based financial modeling, and occupant surveys on willingness to pay (WTP) for resilience improvements. The findings highlight a 70% enhancement in resilience metrics with proposed upgrades compared to code-compliant designs and an 88% reduction in financial risks under extreme weather conditions. Occupant surveys revealed a low WTP for resilience measures, steering the study towards cost-effective strategies. Pre-conditioning techniques improved thermal resilience by 18%, while integrating Phase Change Materials (PCMs) achieved up to a 50% combined improvement. This work contributes to the field by proposing a quantitative resilience framework with flexible Key Performance Indicators (KPIs) for building performance evaluation during outages. It advances modeling methodologies for resilience assessment and offers a multi-objective framework to integrate financial risks into decision-making. The research underscores the gap between WTP and the required investments, identifying scalable low-cost solutions through passive and active strategies. These solutions enhance thermal resilience and economic feasibility, supporting decision-makers in addressing climate change impacts effectively