Open Theses and Dissertations

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  • ItemOpen Access
    Clustering-Based Improved Ant Colony Optimization for the Multi-Trip Vehicle Routing Problem with Heterogeneous Fleet and Time Windows: An Industrial Case Study
    (2025-01-16) Kim, Beom Sae Shawn; Wang, Xin; Wang, Xin; Kim, Jeong Woo; Wang, Yunli; Yang, Hongzhou
    The growing complexity of logistics and transportation systems has led to significant interest in solving Vehicle Routing Problems (VRP) with realistic constraints. Real-world VRP extends beyond minimizing transportation costs to include balancing workloads among drivers, managing heterogeneous fleets, and adhering to strict time windows. Addressing these challenges requires advanced methodologies that ensure operational efficiency, fairness, and adaptability to practical constraints. This thesis proposes a Clustering-Based Improved Ant Colony Optimization (CIACO) algorithm, integrating an improved Ant Colony Optimization (IACO) metaheuristic with advanced clustering techniques, including a modified density-based spatial clustering of applications with noise (DBSCAN-Plus) and a Micro-Cluster Fusion Scheme. The framework addresses the multi-trip VRP with heterogeneous fleet and time windows (MTVRPHFTW), focusing on minimizing total travel distance while handling constraints such as travel time, vehicle capacity, heterogeneous fleet configurations, customer-specific time windows, and multitrip scheduling. Additionally, it ensures balanced workload distribution among vehicles while prioritizing the use of smaller, fuel-efficient vehicles to reduce CO2 emissions, supporting both operational efficiency and sustainability goals. This thesis also discusses the development of an interactive Geographic Information System (GIS) visualization system, implemented via custom Quantum Geographic Information System (QGIS) plugins. Designed specifically to enhance the interpretability and application of the CIACO algorithm, this system bridges optimization results with GIS functionality via custom QGIS plugins, providing logistics planners with dynamic visualizations, route overlays with toggling options, advanced filtering capabilities based on metrics such as CO2 emissions, travel time, travel distance, and vehicle types, and an interactive dashboard for real-time analysis and decision-making support. These interactive features enhance the practicality of the proposed framework for real-world logistics applications, making the solutions more adaptable and actionable. The proposed framework was validated using industrial data from a Canadian logistics company, demonstrating its effectiveness in addressing complex VRP. Experimental results show that CIACO outperforms existing methods in minimizing travel distance, achieving balanced workload distribution, and reducing environmental impact. The interactive GIS system amplifies the practicality of the approach by translating optimization outcomes into intuitive visualizations. This thesis advances VRP research by integrating algorithmic optimization with GIS technologies, addressing modern logistical challenges, and offering scalable solutions for industrial applications.
  • ItemOpen Access
    Typology of Performance in Teams: The Structure of Team Effectiveness and Dysfunction
    (2025-01-18) Pezer, Leah; O'Neill, Thomas; Chapman, Derek; Gevers, Josette; Park, Junho; Turner, Nick; O'Neill, Thomas
    Effective team effectiveness is critical for organizations seeking to thrive in a competitive and dynamic environment, where collaborative efforts are increasingly integral to achieving strategic goals. While it is commonly believed that teamwork is on a spectrum of good to bad in team effectiveness criteria such as performance, viability, and well-being, this assumption has not been thoroughly tested. Questions remain about how these three outcomes interact and relate to each other, and whether there are trade-offs among these outcomes, such as high team performance at the cost of individual well-being. This study was conducted to explore these complexities by shifting the focus from viewing team effectiveness as a single, continuous outcome to examining distinct patterns of effectiveness within teams, where various outcomes coexist and influence each other. Latent Profile Analysis (LPA) was used to test five hypothesized team effectiveness profiles, followed by Multiple Logistic Regression (MLR) to examine how team conditions relate to profile membership. The analysis identified five distinct profiles: Thriving, Striving, Mediocre, Groupy, and Surviving, each showing unique patterns in Performance, Viability, and Well-being. The MLR results had one significant result, indicating 'Purpose' was more likely to belong to the highly effective (i.e., Thriving) profile compared to Mediocre teams. This research contributes to our understanding of team effectiveness by 1) challenging the traditional approach of examining team outcomes separately, proposing instead that these outcomes are multidimensional and interconnected, 2) building on the growing body of person-centered research in the teams literature, and 3) introducing a new taxonomy of team types, offering a practical framework for organizations to classify teams and enhance team effectiveness through targeted strategies.
  • ItemOpen Access
    A Performance Evaluation for DRL-Powered Backscatter Enabled Cognitive FD-WPCN with IRS-Cluster NOMA
    (2025-01-20) Jafari, Reza; Fapojuwo, Abraham O.; Sesay, Abu; Ghaderi, Majid; Cheng, Ben; Abou-Zeid, Hatem
    The increasing demand for massive connectivity, high data rates, efficient spectrum utilization, and continuous power supply to sensors in next-generation wireless networks presents significant challenges, including bandwidth scarcity and energy constraints. To address these issues, we consider a backscatter-enabled cognitive full-duplex (FD) wireless powered communication network enhanced with intelligent reflecting surfaces (IRS) and cluster non-orthogonal multiple access (NOMA), serving as a secondary network (SN) coexisting with a primary network (PN). In this setup, SN sensors access the spectrum without interfering with PN operations and operate in FD mode to nearly double the spectrum efficiency compared to half-duplex transmission. Backscatter communication allows sensors with insufficient stored energy to transmit data without significant delays, supporting real-time applications. To enhance connectivity, mitigate deep fading effects, and provide massive connectivity, we deploy IRS and NOMA techniques. However, increasing the number of sensors raises the complexity of successive interference cancellation (SIC) in NOMA systems. To alleviate this, we employ cluster NOMA, grouping sensors into clusters to reduce SIC complexity via parallel processing. The joint optimization of hybrid access point beamforming, IRS phase shifts, which lie on a unit modulus nonconvex set, and sensor uplink power allocation, under practical constraints such as nonlinear energy harvesting, imperfect channel state information, self-interference due to FD transmission, and limited buffer capacity, results in a complex, high-dimensional, and NP-hard problem. In addition, simultaneous energy harvesting and data transmission in FD mode, together with the energy harvested in one frame that is used in subsequent frames, make the optimization problem frame dependent. To efficiently solve this ergodic problem, we propose a deep reinforcement learning framework based on the twin delayed deep deterministic policy gradient (TD3) algorithm. TD3 effectively handles high-dimensional decision variables and non-convex optimization problems inherent in this system design. Our results demonstrate that TD3 nearly doubles the system’s ergodic sum-rate compared to random allocation and achieves performance comparable to particle swarm optimization but with significantly lower computational complexity and overhead, making it more suitable for large-scale networks. In conclusion, our TD3-based framework provides a scalable and robust solution for complex wireless network architecture, maximizing performance while minimizing computational load. This work advances the state-of-the-art by offering a practical solution for dense networks in next generation networks, addressing key challenges in energy efficiency, fairness, and spectral efficiency.
  • ItemOpen Access
    Exploring Physiologic Markers in the Identification of Vasovagal Syncope
    (2025-01-13) Alsaleh, Mohammed Abdulaziz; Sheldon, Robert; Raj, Satish; Chew, Derek; Phillips, Aaron
    Background: Vasovagal Syncope (VVS) is a common cardiovascular disorder, with at least 40% of individuals experiencing at least one episode in their life and about 20% of adults experiencing recurrent episodes. Traditional diagnostic methods such as the Head-Up Tilt (HUT) test and Implantable Cardiac Monitors (ICM) have significant limitations, including limited availability, high costs, and intensive resource requirements. A novel wearable, beat-to-beat blood pressure (BP) monitor is being developed to address these issues. This device, worn on the ear, samples BP at 50 Hz, stores and streams data, and features a rechargeable battery lasting up to 30 hours. This innovative solution will offer a cost-effective, user-friendly alternative for VVS management, potentially improving diagnostic accuracy and patient outcomes. Aims: We aimed to investigate the potential of a wearable beat-to-beat BP monitor in diagnosing vasovagal syncope. The thesis is structured around the following objectives: Objective 1: Provide a detailed narrative review of vasovagal syncope physiology, the Bezold-Jarisch reflex, and the need for a wearable beat-to-beat BP monitor. Objective 2: Validate the short-term blood pressure fluctuations during scripted physiological changes with a wearable beat-to-beat BP monitor. Methods: The narrative review explores physiological mechanisms underlying VVS, highlighting serotonin's role. For Objective 2 data were collected from 14 participants during activities such as rhythmic breathing and hand grips to validate the ear BP monitor. Spectral and coherence analyses assessed synchronization between the ear monitor and the Modelflow system, with non-parametric methods evaluating statistical differences. Results: The narrative review identified key markers for monitoring VVS. The narrative review identified key markers for monitoring vasovagal syncope (VVS), which guided the validation of the ear BP monitor. Data was successfully collected from 14 out of 20 participants, comprising 47% male and 53% female subjects, with an average age of 24.29 ± 5.61 years. The device demonstrated high coherence values (>0.95) across all activities, indicating strong synchronization with the Modelflow system. No significant differences were observed in systolic BP measurements, with p-values of 0.37 for low-frequency components and 0.18 for high-frequency components, confirming the ear BP monitor's ability to capture BP fluctuations during dynamic physiological changes accurately. Further analysis identified the fundamental heartbeat frequency as 1.4 Hz, with harmonics at 2.8 Hz, 4.2 Hz, and beyond. The coherence of these harmonics highlighted the consistency of the heartbeat-induced waveform shapes, indicating that the arterial blood pressure measurements from the Modelflow and EarBP devices were stable and reliable. Coherence across frequencies revealed comparable signal synchronization between the two devices, with significant coherence observed at the fundamental frequency and its harmonics. Coherence values were tightly clustered near the median across all conditions, with the Valsalva maneuver showing slightly more significant variability due to lower coherence values in some participants. These results collectively validate the ear BP monitor as a reliable tool for arterial pressure measurement and synchronized waveform analysis. Conclusion: This thesis advances the understanding of vasovagal syncope (VVS) physiology and validates using a novel ear-based blood pressure monitor. The narrative review identified key physiological markers and mechanisms, including the Bezold-Jarisch reflex and serotonin signaling, central to VVS episodes. The validation study demonstrated high accuracy and synchronization of the ear BP monitor with established standards, offering a non-invasive, wearable alternative for real-time blood pressure monitoring. While promising, further research is required to expand its validation across diverse populations and address potential limitations such as motion artifacts. These findings support the use of an ear BP monitor as an innovative tool with the potential to diagnose vasovagal syncope.
  • ItemOpen Access
    Queerly Joyful Experiences of K-12 Educators in Calgary, Alberta, Canada: A Policy Analysis and Arts-Based Research Study
    (2025-01-16) Beech, Sarah; Callaghan, Tonya; Danyluk, Patricia; Lacerda-Vandenborn, Elisa
    While much has changed in the last decade in Canada regarding queer inclusion, oppressive hegemonic structures have and continue to perpetuate hetero/trans/allonormativity (the assumption that everyone experiences sexual attraction) and queerphobia in educational settings and the systems that control them. Prior research has lists of suggestions for combatting these systems and structures. Yet, progress is stagnant or even being retracted for queer rights in society and educational contexts. This study looked at how educators and policy created queer inclusion and joy through a lens of optimistic queer theory. The goal of this research was to understand better how queer joy was supported in K-12 schools, what school staff were doing to support queer joy, and why they were choosing to do so. This study looked at the questions: How do queer school staff and self-identified allies see/support queerly joyful practices in some of Calgary's public schools? Why do queer school staff and self-identified allies choose to embrace queer joy? What circumstances allow for fostering queer joy in Calgary public schools? This was captured through policy analysis of nine relevant sexual orientation and gender identity policies that impacted Alberta public school teachers while also drawing upon critical arts-based methodologies to understand better the art of six Calgary educators who upheld queer joy in their work. This research found inconsistencies between the various policies but also indicated the importance of safe spaces, allies, and quality policy to ensure that queer joy could exist in schools in Alberta, Canada.
  • ItemOpen Access
    “No, the Real Question Is…”: A case study of kindergarten students’ meaning construction during dialogically organized read-aloud discussions.
    (2025-01-10) Bence Mathezer, Michelle; Aukerman, Maren; Aukerman, Maren; Boyd, Maureen; Spring, Erin; Lenters, Kim; Burwell, Catherine
    This qualitative single case study explores how kindergarten students construct understanding of picturebook read-alouds through idea-sharing in a dialogic classroom setting. The aim was to investigate the processes by which young children engage in the co-construction of textual meanings and develop a knowledge authority role in dialogically organized read-aloud discussions. Over seven months, weekly dialogically organized read-aloud discussions were facilitated with 20 ethnically and academically diverse kindergarten students. Data from 10 book discussions were analyzed using sociocultural discourse analysis and fine-grained conversation analysis to examine students' idea-sharing. The central research question addressed how young students construct meaning through idea-sharing during dialogically organized read aloud discussions, while sub-questions explored variations in the ideas shared, changes over time, and the functions of these shared ideas in the social construction of students' meaning-making. The findings reveal that students' idea-sharing was a complex, individualized process, where each student drew upon personal resources to construct deeply meaningful interpretations of the text. While their interpretations were highly personalized, they were also malleable and evolved in response to peers’ contributions. Analysis of language patterns within the idea-sharing indicated that the students' shared ideas changed over the length of the project. By the end of the study, students employed a greater range of resources, their verbalized ideas became lengthier, contained more reasoning words and included more textual theorizing suggesting the students were engaging increasingly complex textual understandings. Furthermore, the findings suggest three critical factors in the dialogic discussions that aided students’ meaning construction; (a) exposure to shared ideas helped highlight diverse textual ideas for students to explore, (b) unconstrained idea-sharing made visible the thinking processes students engaged in and provided a starting point to collaboratively build off of and, (c) discussions held students accountable to think deeply about the text, explain their interpretations positioning these young students as active textual interrogators. These findings underscore the importance of dialogic environments in supporting young children to become confident and reflective meaning-makers, leveraging both their own and their peers’ resources to construct robust textual understandings. Recommendations for teachers and administrators are provided.
  • ItemOpen Access
    Cyclic Carbon Dioxide Sequestration Integrated with Geothermal Energy Production
    (2025-01-16) Tai, Nan; Gates, Ian; Chen, Shengnan (Nancy); Hu, Jinguang; Hejazi, Hossein; Luo, Peng
    Faced with the challenges of climate change caused by rising greenhouse gas emissions, society is turning to clean energy alternatives. Two key methods being considered are carbon capture, utilization, and storage (CCUS) and geothermal energy. Currently, researchers are focusing on combining these two technologies and this study provides a novel cycle method to integrate CO2 sequestration with geothermal energy production. In the first study, a single well cyclic CO2 injection and hot water production in the Basal Cambrian Sandstone Unit (BCSU), Canada is studied. In the second study, by using cyclic operation, multiple wells with various working modes and operation types are applied in the BCSU for combining CO2 sequestration with geothermal energy production. The third study involves water co-injection with CO2 in both cyclic and continuous modes, aiming to integrate CO2 storage with geothermal energy extraction in the BCSU. In the last study, economic analysis is applied to evaluate the profitability of the designed cyclic and continuous cases with various injection fluid combinations (CO2 and water) in the BCSU. First, the results indicate that in a single well scenario, the designed cyclic system can achieve both CO2 storage and geothermal energy extraction successfully, though the injected CO2 is partially produced along with hot water during the production period due to its high mobility and proximity to the well. Second, the designed multi-well cyclic operation can not only combine CO2 storage with geothermal energy production but achieve net zero emission CO2 storage process during the operation. Third, compared with pure CO2 injection, water injection not only enhances CO2 storage percent significantly with cyclic techniques, but can help achieve net-zero emission cyclic CO2 storage system with geothermal energy production. Fourth, pure geothermal energy production in the BCSU is generally unprofitable, but integrating CO2 injection by using cyclic method can make a satisfactory profit due to successfully sequestering a certain amount of CO2 in the target formation under the positive carbon credit policy. This study evaluates the feasibility of using novel cyclic method to integrate CO2 sequestration with geothermal energy production in the specific formation, which makes contributions for both CCUS and geothermal energy towards carbon neutrality society.
  • ItemOpen Access
    Associations Between Socioeconomic Position and Mental Health and Mental Health Disorders Among Adults in Canada from 2005 to 2022
    (2025-01-16) Yin, Shelly; Olstad, Dana Lee; Godley, Jenny; Patten, Scott
    Introduction: Socioeconomic position (SEP) is a fundamental determinant of mental health, often measured by income and education. Poor mental health and mental health disorders are more prevalent among adults with a lower SEP. Examining trends in associations between SEP and mental health outcomes can inform policies to reduce mental health inequities, yet these trends remain understudied. I aimed to examine (1) associations between SEP and mental health outcomes in 2022 and (2) trends in associations from 2005-2022. Methods: I used data from the Canadian Community Health Survey (2005, 2007-2022) to examine associations between SEP (annual household income, educational attainment) and mental health outcomes (fair/poor self-reported mental health (SRMH), mood disorders, anxiety disorders) among adults (≥23 years) in the ten provinces using multivariable logistic regression. I adjusted for sex, age, marital status, immigration status, race/ethnicity, and Indigenous identity and tested for modification by sex. I repeated logistic regression models for each cycle and assessed trends with random-effects meta-analysis and meta-regression. Results: In 2022, the odds of all mental health outcomes were lower with high and middle than low income and education. Associations were stronger with income than education and persisted after mutual adjustment. High income was more protective against poor/fair SRMH and mood disorders among males than females, while high education was more protective against anxiety disorders among females than males. Income and education were associated with all mental health outcomes from 2005-2022. Associations with poor/fair SRMH weakened in 2020-2022 during the COVID-19 pandemic compared to before 2020. Associations with mood disorders remained stable from 2005-2022. Trends with anxiety disorders were mixed. Conclusion: Higher income and education were associated with lower odds of adverse mental health outcomes in 2022. My study was the first to examine trends in associations and found that inequities persisted from 2005-2022. Inequities in poor/fair SRMH weakened in 2020-2022, while most inequities in mood and anxiety disorders remained stable. Policies that increase household incomes and support higher educational attainment may help reduce inequities. Future research may investigate policy responses to the COVID-19 pandemic that may have reduced certain mental health inequities in 2020-2022.
  • ItemOpen Access
    Caregiver-Child Attachment in Early Childhood: A Multi-Method Investigation of Caregiving Antecedents and Socioemotional Outcomes
    (2025-01-14) Cooke, Jessica Elizabeth; Madigan, Sheri; Giesbrecht, Gerald; Noel, Melanie; Benzies, Karen; Guyon-Harris, Katherine
    Background: As reviewed in Chapter One, attachment interventions aim to improve caregiver-child attachment relationships by targeting insensitive and disrupted forms of caregiving behaviors. While these interventions are moderately effective at enhancing attachment security and reducing disorganization, their expected downstream impacts on children's internalizing and externalizing problems are inconsistent, revealing gaps in the literature. Thus, the aim of this dissertation was to advance the understanding of the complex relations between caregiving antecedents, caregiver-child attachment, and children’s socioemotional outcomes. Method: Chapter Two examined the combined and interactive longitudinal effects of sociodemographic risk, observed maternal disrupted caregiving, and maternal self-reported depression, psychopathology (i.e., substance use, psychosis, and posttraumatic stress), and childhood maltreatment history on observed infant attachment disorganization using longitudinal data analysis within a Canadian pregnancy cohort of 285 mother-infant dyads. Chapter Three meta-synthesized associations between observed caregiver sensitivity and children’s internalizing (k = 69) and externalizing (k = 94) problems. Sample and measurement characteristics were explored as potential moderators. Chapter Four investigated the longitudinal direct and indirect effects of observed maternal disrupted caregiving and its subdimensions on children’s internalizing and externalizing problems at 24 and 36 months in the same cohort from Chapter Two. Attachment disorganization was explored as a potential mediator of associations. Results: In Chapter Two, sociodemographic risk, maternal disrupted caregiving, and their interaction significantly predicted infant attachment disorganization. Sociodemographic risk was associated with greater attachment disorganization when disrupted caregiving was high, but not when it was low. In Chapter Three, caregiver sensitivity was significantly related to children’s internalizing and externalizing problems, with stronger associations found for externalizing problems compared to internalizing problems. Socioeconomic status, publication status, and the measure of caregiver sensitivity emerged as moderators of associations with internalizing problems. In Chapter Four, maternal disrupted caregiving and several subdimensions of disrupted caregiving were associated with infant attachment disorganization. In addition, the subdimension of maternal negative-intrusive behaviors directly predicted children’s externalizing problems at 24 and 36 months and children’s internalizing problems at 36 months. However, attachment disorganization was not related to children’s externalizing or internalizing problems, and attachment disorganization did not mediate the associations between maternal negative- intrusive behaviors and children’s behavioral outcomes. Conclusion: As discussed in Chapter Five, findings from the current studies illustrated that the associations between caregiving antecedents, caregiver-child attachment, and children's behavioral outcomes are complex. In this dissertation, caregiver sensitivity and disrupted forms of caregiving were important antecedents of attachment and socioemotional outcome in children. In addition, sociodemographic risks appeared to elucidate some of the complexities within these dynamics. Thus, by addressing insensitive and disrupted forms of caregiving, in conjunction with an integration of multifaceted approaches to mitigate the social determinants of health, practitioners and policymakers may cultivate more supportive environments for both caregivers and children, ultimately fostering improved emotional and behavioral outcomes for future generations.
  • ItemOpen Access
    Enhanced Oil Recovery from Shale Reservoirs by Huff and Puff Carbon Dioxide and Hydrogen Injection, Safe Permanent Storage of Carbon Dioxide, Temporary Storage of Hydrogen and Life Cycle Assessment: A Contribution to “Net Zero” Emissions
    (2025-01-10) Bao, Xiaolin; Aguilera, Roberto; Moore, Robert Gordon; Mehta, Sudarshan (Raj); Chen, Zhangxing (John); Sarma, Hemanta; Wang, Jiexiang
    Oil production from shale reservoirs has gained attention particularly since the early 2000’s. Oil recovery factors from multi-stage hydraulically fractured horizontal wells have generally been reported to range between 5 and 10% during primary production. This thesis shows that oil recoveries can be significantly improved by conducting huff ‘n’ puff gas injection in shale reservoirs performing under geologic containment, i.e., reservoirs where hydrocarbon fluids are in an inverted position vis-à-vis gravity within the same layer(s) in a given structure. In this research, huff ‘n’ puff CO2, H2, and flue gas injection are investigated using reservoir simulation leading to the following original contributions applicable to shale petroleum reservoirs: (1) a significant increase in oil recovery, (2) safe storage of CO2 on a permanent basis, (3) safe storage of H2 on a temporary basis, and (4) safe storage of flue gas on a permanent basis. In addition, an original multiple sweet spot detection method is developed using a combination of machine learning (ML) and modified Picket plots. All these findings contribute to a possible future with net-zero emissions. The proposed methodology calls for the following procedure (using CO2 as an example): (1) start huff ’n’ puff CO2 injection after the well goes on oil production for 2 or 3 years; thus, the shale reservoir is essentially undepleted, (2) store CO2 gradually in the shale reservoir during the huff periods, and (3) store CO2 continuously once the huff ’n’ puff project is finalized until reaching the initial reservoir pressure. The simulation model includes a history match period with actual production data from a pilot horizontal well of the Eagle Ford Shale in Texas, and forecast periods with huff ’n’ puff CO2, H2, and flue gas injection. The initial reservoir pressure is never exceeded during the life of the project as a safeguard against possible leaks stemming from the creation of new fractures or reactivation of faults. The inclusion of Life Cycle Assessment in the proposed methodology helps to achieve an outcome that is beneficial for improving economics and externalities and consequently helps to balance important pillars of sustainability: society, the environment and economics.
  • ItemOpen Access
    Well-Defined Implementations and Patentable Subject Matter
    (2025-01-15) Lambert, John; Hagen, Gregory; Hagen, Gregory; Laidlaw, Emily; Ilg, Michael
    The Canadian jurisprudence relating to subject-matter patentability has developed errors that are inconsistent with over a century of comparatively stable interpretation of s. 27(8) of the Patent Act. The errors are the adoption of a physicality requirement and an approach to identifying the bar against mere scientific principles and abstract theorems that discounts the actual implementation of the invention and focuses instead on the form of the invention by looking for physical components or effects. This approach also is characterized by the failure to separately consider the issues of the bar against mere scientific principles, obviousness, indefiniteness, overbreadth/lack of support and meeting the definition of invention. The historical development of s. 27(8) and s. 2 of the Patent Act is analyzed and the origins of these errors are discussed, including a review of the most recent relevant jurisprudence. A more correct and concise approach to determining subject matter patentability would evaluate s. 27(8), after purposive construction, purely on the basis of whether the invention as claimed recites a well-defined application and specific implementation of the scientific principle or abstract theorem. A more correct determination of whether a claimed invention meets the definition set out in s. 2 would identify whether, after purposive construction, the invention has a utilitarian application for the benefit of humanity that does not fall within the liberal arts or another judicial exception. Separately from these determinations, and in no particular order, the other requirements for patentability may also be considered.
  • ItemOpen Access
    All-Pass Delays and Residue Amplifier for a 10-GS/s Non-Blocking Subranging ADC
    (2025-01-08) Kabirkhoo, Zahra; Belostotski, Leonid; Maundy, Brent JP; Murari, Kartikeya
    Delay circuits play a critical role in various applications, notably, in recent years, analog delays have been utilized in certain analog-to-digital converter (ADC) architectures, including continuous-time pipelined ADCs (CTP-ADCs) and non-blocking subranging ADCs (NBSADCs), where they help improve the overall ADC speed and/or resolution. In this work, the proposed delay circuits are specifically tailored for a 10-GS/s, 8-bit non-blocking subranging ADC (NBS-ADC) intended for radio telescope applications. First, this thesis proposes a high-order all-pass-filter (APF) circuit topology. The design process and tunability are explored using both TSMC 65-nm-CMOS and 22-nm FDSOI CMOS technologies. The proposed 6th-order APF, implemented in TSMC 65-nm-CMOS, achieves a delay range from 250 ps (BW10%=0–8 GHz) to 400ps (BW10%=0–5 GHz) having the state-of-the-art DBW10%=2. Additionally, 3rd- and 4th-order APFs were subsequently designed in GlobalFoundries 22-nm FDSOI CMOS for a 5G beamforming receiver operating from 24.3 to 28.7 GHz. The 3rd- and 4th-order APFs exhibited 9-to-21 and 21-to-36 ps delay ranges, respectively, to generate beams from 0° to 35°. Also, in further steps we sought a solution to eliminate inductors entirely, leading to the design of a compact, inductorless, cascadable GHz-frequency APF delay circuit. Results obtained using a TSMC 65-nm-CMOS containing 4 cascaded APF cells, exhibiting a delay tuning range of 300 to 500 ps over a 0.1-to-4-GHz bandwidth. The filter occupies an active area of 0.04 mm2 and dissipates 6.2 mW/cell from a 1.3-V supply. The APF achieved a delay-per-area metric that is at least 1.6 times greater than that of previous gm-C APFs, while also operating across a wider bandwidth. It exhibited a high delay-bandwidth product (DBW) of 1.95, all while maintaining a gain of 3.3 dB. Finally, we presented a novel residue generation and amplification (RGA) stage that employs inductive peaking and a tunable-gain post-amplifier reaching a high gain and a wide bandwidth, for a 10-GS/s, 8-bit NBS-ADC intended for radio telescope applications.
  • ItemOpen Access
    Effects of Human Activities and Natural Processes on Wolverine Populations
    (2025-01-16) Mirjam, Barrueto; Musiani, Marco; Barclay, Robert; Clevenger, Anthony Paul; Jacob, Aerin L; Cork, Susane Catherine; Darimont, Christopher Tod
    Understanding the dynamics of large-carnivore populations is critical in light of expanding human activities that may alter their natural habitats. In this thesis, I examine the effects of both human-induced disturbances and natural environmental factors, on the population density and habitat use of wolverines (Gulo gulo) in the Canadian Rocky Mountains and the Columbia Mountains of British Columbia and Alberta, Canada. Carnivores, such as wolverines, are sensitive to human-caused mortality and large-scale habitat changes as they roam widely and have low reproductive rates and densities. Human impacts, including overharvest, ecosystem changes due to resource extraction and additional decreases in habitat quality because of recreation, may pose growing challenges to wolverine conservation. I employed non-invasive genetic sampling, remote camera surveys and spatial capture-recapture techniques to assess population trends and offer critical insights into how wolverines respond to both human-caused pressures and natural environmental factors. Sampling at a population scale, my research provides evidence that recreational activities not only impact habitat use, but can have detrimental impacts on wolverine population density, even within protected areas. While protected areas appear to be vital for maintaining wolverine populations, especially if they are harvested on unprotected lands, edge effects and high disturbance levels from recreation may compromise their effectiveness. My work thus suggests that human disturbances have both direct and indirect effects on wolverine density, with female wolverines being particularly impacted. Areas with higher road density and recreational activity exhibit lower population densities, highlighting the need to manage human access if protection is a societal objective. I also investigated the role of bottom-up factors, such as persistent spring snow cover, which is associated with wolverine ecology and reproduction. The interaction between natural and anthropogenic factors creates complex patterns in habitat use, but by identifying key drivers of population decline, I offer important conservation implications, emphasizing the necessity for integrated management strategies that balance human land use with the needs of wildlife species. These findings underscore the broader applicability of my research to other carnivores facing similar threats, providing a foundation for future conservation efforts.
  • ItemOpen Access
    Evaluation of Glutamine Metabolism and Cellular Stress Responses in Fibroblasts from Patients with Mitochondrial Disease
    (2025-01-20) Alhasan, Karm; Greenway, Steven; Lewis, Ian; Khan, Aneal; Sinasac, David
    Background: Mitochondrial diseases (MDs) are a group of genetic disorders with diverse patient phenotypes resulting from mitochondrial dysfunction. Pathologies are often poorly understood, and therapies are limited. Previously, we identified abnormalities in glutamine metabolism as well as an upregulation of the integrated stress response (ISR) and mitochondrial unfolded protein response (UPRmt) in dermal fibroblasts of patients with the dilated cardiomyopathy with ataxia syndrome (DCMA), a systemic mitochondrial disease (MD) caused by deficiency of DNAJC19. However, it is unclear whether these changes are unique to DCMA or shared across other MDs. Aims: To investigate changes in glutamine metabolism and stress responses in dermal fibroblasts from patients with Barth Syndrome (BTHS), complex I deficiency (C1D), and Kearns-Sayre syndrome (KSS) and healthy fibroblasts treated with mitochondrial disruptors. We hypothesized that, regardless of cause, mitochondrial dysfunction will lead to abnormal glutamine metabolism and activation of the ISR and UPRmt. Methods: Fibroblasts from healthy individuals (N=6) and patients with a diagnosis of BTHS (N=2), C1D (N=3) and KSS (N=3) were cultured in media containing heavy isotope-labelled glutamine [5-13C 2-15N]. After 48 hours, extracellular media was extracted and metabolites were quantified using liquid-chromatography-mass spectrometry (LC-MS). To validate findings, we also treated healthy fibroblasts (N=2) with dinitrophenol (DNP) and rotenone. The expression of ISR- and UPRmt-associated genes was quantified via qPCR. Results: Levels of the dual-heavy isotope-labelled glutamine (5-13C 2-15N) and glutamine-derived isotopomers were not significantly different in C1D, KSS and BTHS, compared to controls. In healthy fibroblasts, DNP (1 mM) reduced 5-13C 2-15N glutamine uptake, whereas rotenone (100 nM) had no effect. The ISR and UPRmt were not upregulated in BTHS, C1D, or KSS although data were limited by small numbers. Exposure to 500 nM rotenone and 1 mM DNP significantly upregulated ISR/UPRmt-associated genes ATF4 and ATF5 in healthy fibroblasts. Conclusions: These preliminary findings suggest that glutamine metabolism and the activation of cellular stress responses in MD fibroblasts differs depending on extent and/or etiology of mitochondrial dysfunction. Our results support the observation that DCMA fibroblasts have a unique dysregulation of glutamine metabolism and stress responses which may have implications for pathophysiology and treatment.
  • ItemOpen Access
    Stream Starting Soon: Exploring Theatrical Design Principles to Evoke Feelings of Safety for Livestreamers
    (2025-01-14) Colins, Mathilda; He, Helen Ai; Viczko, April; Aycock, John Daniel; Leblanc, Jean-Rene
    Toxic behaviour is prevalent in livestreaming communities, particularly for minority groups such as LGBTQ+, POC, and women. To combat this, current solutions employ automatic or human content moderation. While necessary, moderation is a content-based intervention that is largely reactive, removing harmful content after it has already been posted. Drawing inspiration from physical theatre, I explore an alternative approach that seeks to create digital safe spaces by proactively fostering positive emotions for the livestreamer so that they engage in behaviours that encourage feelings of safety for others in their community. I leverage the field of theatre and the elements and principles of design to offer a Framework of Controllable Qualities, where “Controllable Qualities” refers to customizable audiovisual sensory cues used to create a particular mood or atmosphere in a space (such as the volume of a Sound, the colour of a Light, or the texture of a Costume). I illustrate the application of my framework with four manually-created design probes (background images informed by the framework) deployed by participating livestreamers in a small, exploratory qualitative study. The design probes aimed to foster a spectrum of feelings of safety from extremely safe, to extremely unsafe. Through a qualitative study, I examine the values and practices that livestreamers and moderators held surrounding the creation of digital safe spaces, and if the presence of the design probes influenced feelings of safety for the livestreamer. Drawing on their feedback, I created a computational program built in Processing to automatically generate design probes. I make four contributions: 1) a richer understanding of how to translate physical theatrical design elements to a digital livestream context through the creation of a Framework of Controllable Qualities, 2) the application of a subset of the Framework of Controllable Qualities to inform the design of manual and automatically generated design probes to foster feelings of safety, 3) a deeper understanding of livestreamer and moderator practices to foster safety and inclusivity within a livestream community, and 4) an understanding of livestreamer and moderator experiences with the manually-created design probes and its influence (if any) on feelings of safety for the livestreamer.
  • ItemOpen Access
    Disease control practices used to prevent morbidity and mortality in preweaned beef calves
    (2025-01-15) Sanguinetti, Virginia Margarita; Windeyer, Claire; Checkley, Sylvia; Adams, Cindy; Campbell, John; Morley, Paul; Smith, David
    Calf morbidity and mortality negatively impact economic returns for cow-calf producers. Given this, preventing infectious diseases, including Neonatal Calf Diarrhea (NCD) and Bovine Respiratory Disease (BRD) is essential. However, recommended practices to attain this have not been recently summarized or updated. Therefore, the aim of this thesis was to study several aspects relevant to the implementation of disease control and update recommended practices. The objectives were to: i. summarize the scientific evidence on the effectiveness of practices in preventing health and mortality outcomes, ii. prioritize practices based on their usefulness in herds considering their effectiveness, ease of implementation, and economic feasibility, iii. assess the frequency of outbreaks, use of practices, the impact of practices on outbreaks across Canadian cow-calf herds, and the importance given to productivity parameters across regions, and iv. compile the evidence into a Calf Health Decision Tool to support discussions between producers and veterinarians and pilot it in Alberta, Canada. The work reported in Chapter 2 showed that the evidence of the impact of practices on mortality, regardless of the cause, was scarce. Only a few practices showed statistically significant associations. Herds that routinely intervened with colostrum or checked the fullness of the udder had a lower mortality risk than those not using these practices. Herds that calved early or during winter had a higher mortality risk than those calving later. Herds with longer calving seasons had a higher mortality risk than those with shorter seasons. Calves from herds that did not supplement with vitamin E and selenium at birth had higher odds of mortality than those from herds where this practice was used. Chapter 3 showed that most practices impacted both NCD and BRD. However, the evidence was of low and very low certainty. Chapter 4 found that veterinarians prioritized the effectiveness of a practice over its ease of implementation and economic feasibility. Vaccinating calves against clostridial disease and providing colostrum in case a calf had not nursed using an oesophageal tube or nipple bottle were practices considered always useful for all herds. Most practices were shown to have intermediate levels of usefulness in herds. Prophylactic and metaphylactic use of antibiotics were considered among the least useful. Yet, all practices that were considered at least very useful for some herds were deemed relevant enough to be included in a Calf Health Decision Tool. Chapter 5 found that over 40% of herds had at least one type of outbreak during the last three calving seasons. Also, it was demonstrated that eastern and western herds managed their cow-calf herds differently. Some frequently used practices were shown to increase the odds of having outbreaks. It was also found that western and eastern producers gave similar importance to several productivity parameters of their herds. In Chapter 5, it was revealed that the Tool was useful for facilitating discussions between producers and veterinarians regarding disease control. Responses showed that delaying the calving season for early calving herds was not feasible. Most herds could only follow only one of two recommended practices, either calving heifers before cows or calving seasons shorter than 80 days. Therefore, there might be an incompatibility between these recommendations. Most producers were willing to consider using some method to segregate calves by age. Given this, this could become a more widespread recommended practice. Only half of the herds vaccinated dams against NCD, and even one herd with a history of NCD outbreaks was not doing this. This may be because producers felt reluctant to manage pregnant dams in the chute. However, they were more willing to consider calf vaccination instead. The findings presented in this thesis reveal a general lack of consistent evidence proving the effectiveness, ease of implementation, and economic feasibility of practices. Overall, the work in this thesis showed that many commonly used practices make herds vulnerable to outbreaks, and thus, tailoring disease control practices to the operation is essential. Therefore, The Calf Health Decision Tool created may help support discussions between veterinarians and producers to implement this and prevent disease and mortality.
  • ItemOpen Access
    Building Better from LEED to Living: An Approach to Net Zero Water Management
    (2024-12) Fatima, Kulsum; Assefa, Getachew; Tyler, Mary Ellen; Hilmi, Tawab
    In view of the increased concerns about the United Nations Sustainable Development Goals (UNSDGs), there is a need to minimize water-related challenges and maximize water security and availability through sustainable green building practices. As significant water consumers, university campuses play a crucial role in addressing water-related challenges. By focusing on water-efficient buildings to achieve net-zero water management and exploring the influence of green building practices, universities can contribute to the UNSDGs, particularly in promoting sustainable water management, climate action, and the development of resilient communities. This thesis explores the influence of green building practices on water management by comparing objectives, directives, and applications suggested by the LEED certification system and the Living Building Challenge (LBC) certification system. It aims to understand the advantages and challenges in transitioning UCalgary from LEED-guided water-efficient operations to LBC-compliant net-zero water operations. This research evaluates best practices from three design precedent sites: CIRS at the University of British Columbia, Bullitt Center with the University of Washington, and Kendeda Building at Georgia Institute of Technology. For this purpose, two evaluation frameworks are used: Performance Assessment Framework (PAF) and Water Literacy Assessment Framework (WLF). UCalgary and design precedent sites are evaluated using the PAF and WLF frameworks to identify challenges and barriers to water performance efficiency and improve water management practices. This research hopes to encourage decision-makers and practitioners at higher education institutions (HEIs) to achieve net-zero compliance as per LBC, minimize performance gaps and water-related challenges, motivate water managers to develop an operational net-zero water scenario, and incentivize water users to support this scenario by promoting good water use behaviours on HEI campuses. This research provides insights into the factors influencing the adoption of LEED and LBC at higher education institutions. It also highlights the challenges and barriers project teams involved in LEED and LBC applications face. Additionally, the research identifies problem situations related to selecting and determining water strategies for LBC compliance. The understanding gained from this research is valuable for addressing the complexities of water management and promoting the appreciation and value included in the joy and everyday understanding of water.
  • ItemOpen Access
    Integrating Queue Dynamics into the Trip-Based Macroscopic Fundamental Diagram
    (2025-01-15) Hassanin, Omar; Kattan, Lina; Demissie, Merkebe Getachew; He, Jianxun (Jennifer)
    Macroscopic traffic models provide a simplified framework for analyzing and controlling traffic at the network level. Among these models, the trip-based macroscopic fundamental diagram (MFD), or generalized bathtub model, effectively captures inflow, accumulation, and outflow while considering trip lengths and travel times, particularly under rapidly changing traffic conditions. This study addresses a gap in the trip-based MFD, which lacks queuing dynamics under downstream restrictions, as its original outflow function assumes unrestricted flow. To resolve this, the research incorporates downstream queuing dynamics, accounting for waiting times and their changes over time. The study also examines the impact of connected and automated vehicles (CAVs) on traffic dynamics through numerical simulations. Assuming that CAVs improve the MFD shape and bottleneck capacity, a sensitivity analysis was conducted for various market penetration rates (MPRs). Key findings include: 1) Average upstream waiting time decreased from 130 seconds to 0 at 60% MPR; 2) Average reservoir travel time reduced by 60% (570 to 230 seconds) at 100% MPR; 3) Average downstream waiting time initially increased by 25% at 70% MPR but fell by 12.5% at 100% MPR; and 4) Average total trip time (TTT) dropped by 61%, from 780 to 300 seconds. The results show earlier commuter exits, shifting the peak time (𝑡𝑝) of TTT. However, as 𝑡𝑝 depends on external factors (e.g., work schedules), the inflow demand pattern was adjusted to maintain 𝑡𝑝 constant, revealing a 26-minute inflow peak shift at 100% MPR. Additionally, congestion duration reduced by 51%, from 96.6 to 46.6 minutes, while maximum travel time decreased by 66% (18.5 to 9.5 minutes). Lastly, previous enhancements in capacities maintained constant free-flow speed (𝑣𝑓) for safety reasons. However, when the MPR reaches 100% and there are no longer any human-driven vehicles, increasing 𝑣𝑓 no longer poses safety risks. Thus, 𝑣𝑓 can reach 21m/s instead of 15 m/s, leading to less congestion. The findings demonstrate that CAVs significantly reduce trip time and congestion but cannot alone eliminate the negative impacts of downstream bottlenecks.
  • ItemOpen Access
    Assessing Multi-Coil Deep-learning-based MR Image Reconstruction
    (2025-01-11) Dubljevic, Natalia; Frayne, Richard; Souza, Roberto; Bayat, Sayeh; Levan, Pierre
    Magnetic resonance (MR) imaging is a valuable non-invasive imaging technology essential for diagnostics and patient health management. However, scan times are often quite long, affecting both patient throughput and comfort. To help accelerate the process, parallel imaging uses an array of receiver coils to reduce the amount of data acquired. Recently deep learning (DL)-based MR image reconstruction has become popular as it allows for further scan acceleration. With its advent, new questions are raised regarding optimal coil design and processing strategies. This work investigates whether traditional geometric coil constraints imposed by parallel imaging can be relaxed when using DL-based reconstruction methods as compared to non-DL approaches. We also explore whether to first combine channels (coil-combined approach) to enhance model generalizability or to keep channel processing separate (all-coil approach) to fully utilize multi-channel information. Two sets of head coil profiles (8-channel and 32-channel geometries) were evaluated across three methods: a DL model, conjugate gradient SENSE (CG-SENSE), and L1-wavelet compressed sensing (CS). These methods were compared using both quantitative metrics and visual assessment as coil overlap increased. Results showed that as coil overlap increased, performance significantly decreased (p<0.001) across all methods, with the largest impact seen in CG-SENSE. DL-based reconstructions consistently outperformed their non-DL counterparts, with minimal changes in performance across coil overlap and signal-to-noise ratio (SNR). While CS demonstrated better robustness to coil overlap than CG-SENSE, it produced inferior reconstructions characterized by blurriness. Additionally, we assessed three popular DL architectures using both coil-combined and all-coil strategies on brain MR images in and out of distribution. All-coil styles slightly improved in-distribution performance, such as when reconstructing data from healthy individuals, while coil-combined designs better generalized to unseen pathological data. These findings suggest that DL-based reconstruction can produce high-quality images that are robust to coil overlap, offering the potential to relax geometric coil design constraints. Additionally, a coil-combined processing approach may be preferable when considering clinical use.
  • ItemOpen Access
    An Attention-Based Deep Learning Approach for Forecasting Electricity Prices in Real-Time Electricity Markets
    (2025-01-15) do Carmo Junior, Jose Eustaquio; Zareipour, Hamidreza; de Souza, Roberto Medeiros; Papalexiou, Simon Michael
    Real-time electricity markets are characterized by irregular and sudden price swings, leading to high price volatility and significant uncertainties for market participants. Accurate and informative electricity price forecasts are essential to reduce these uncertainties and enable more effective decision-making in energy generation, consumption, strategy planning, and risk management. This thesis presents a new forecasting framework for electricity prices in real-time markets, leveraging the capabilities of deep learning and advanced feature engineering. The proposed methodology integrates the Temporal Fusion Transformer (TFT), a deep learning model applied to time series forecasting, with dynamic clustering techniques to enhance forecasting accuracy. This is done by combining Hierarchical Density-Based Spatial Clustering of Applications with Noise and Dynamic Time Warping to cluster generators based on attributes such as geographical location, fuel type, installed capacity, and generation patterns. These clusters provide new covariates for forecasting models, enabling the method to adapt to the unique characteristics of any electricity market. The effectiveness of the proposed framework is demonstrated through a case study of the Ontario electricity market, where the methodology outperforms the forecasts of the system operator in terms of average error, accuracy, precision, and recall across a six-hour forecast horizon. This study underlines the framework's versatility and offers valuable insights into electricity price behavior, aiding market participants in mitigating risks and optimizing energy strategies.