Digital Commons Network^™

Heterogeneous Robots Cooperation Via Multi-Agent Reinforcement Learning, Rehab Uddin Shawon

Graduate Theses/Dissertations

Enabling heterogeneous robots with diverse capabilities, roles, and task responsibilities to coordinate effectively in complex, dynamic environments remains a fundamental challenge in autonomous multi-robot systems. Multi-Agent Reinforcement Learning (MARL) provides a promising framework for decentralized cooperation. However, most existing MARL approaches assume homogeneous agents or fixed single-task settings and suffer significant performance degradation as the number of robot and task types increases. This thesis presents a scalable shared-policy MARL framework that allows heterogeneous robots to learn specialized behaviors for individual, sequential, and collaborative tasks involving temporal and spatial dependencies through a single neural policy. I first embed robot identity directly …

Advancing Hate Speech Detection: Binary And Multiclass Approaches From Traditional Methods To Parameter-Efficient And Ontology-Guided Language Models, Mahmoud Abusaqer

Graduate Theses/Dissertations

The widespread proliferation of hate speech on social media platforms poses significant challenges for content moderation and user safety, requiring automated systems that are simultaneously accurate, efficient, and capable of fine-grained distinctions. This thesis investigates hate speech detection through five published manuscripts organized into two complementary threads: binary detection (hateful vs. non-hateful) and multiclass detection across demographic targeting categories. The binary thread progresses from a broad 38-model baseline spanning traditional machine learning, deep learning, and transformer architectures (where RoBERTa reaches 91.48% accuracy and CatBoost remains competitive at 88.60%) to parameter-efficient adaptation, in which Low-Rank Adaptation (LoRA) of large language models …

Engaging Elementary Music Students Through Multisensory Teaching In A Kodály-Inspired Classroom, Chelsea Taylor

Graduate Theses/Dissertations

Multisensory teaching is an instructional approach that is increasingly implemented in general education classrooms. Although it has been widely studied in special education settings and in the teaching of reading skills, it has not been extensively examined within music education. The purpose of this study was to examine the impact of multisensory instruction on student engagement, comprehension, and retention of concepts in my elementary music classroom. Through Kodály-inspired lessons that challenged students to audiate pitches while kinesthetically building a pentatonic scale, notate music on textured surfaces, and play games that incorporated simultaneous sensory input, these lessons intentionally integrated visual, auditory, …

Development And Validation Of The Ipip-Ocean: A Hierarchical Facet-Level Measure Of The Big Five, Caleb Niccum

Graduate Theses/Dissertations

This study focused on developing a mid-range, hierarchical, five-factor, 20-facet personality inventory (the IPIP-OCEAN) composed of 100 items drawn from both the IPIP-NEO-300 and the Abridged Big Five Circumplex. Hierarchical confirmatory factor analysis was used to validate the factor structure. Depression and anxiety, measured with the PHQ-9 and GAD-7, were used to further validate the measure through discriminant and convergent validity by examining whether the domains and facets of the IPIP-OCEAN produced findings consistent with those reported for similar scales in prior depression and anxiety research. Numerous factor analyses were conducted on the IPIP-OCEAN dataset (N = 1,058), and a …

Herp Count 2025, Camryn Gulledge

Graduate Theses/Dissertations

Herp Count 2025 is a process-based project in which I log and document every herp (reptile or amphibian) I encounter in the wild while investigating the realities of human impact on ecosystems. During 2025, I observed 1,406 individual herps, most of which appeared not in remote wilderness but in the compromised margins of human spaces. When I observe them in a littered area, I collect nearby trash and bring it back to my studio to combine it with a detailed drawing of that specific individual. In my Contact series, I use a clean-touch printmaking process that involves a stretched plastic …

Remediation Impacts Metal Concentrations And Metal Tolerant Bacteria In Soils Of The Missouri Tri-State Mining District, Ophelia R. Pettington

Graduate Theses/Dissertations

After over 100 years of Zn and Pb mining in the Tri-State mining district (TSMD), former mines continue to be sources of metals. Metal contaminated soils can be remediated using plant-microbe interactions. Plants manipulate their microbiome and recruit microbes to increase metal tolerance. Remediating bacteria are site-specific and identifying native microbes can accelerate remediation efforts. Studies relating microbes and metal concentrations in remediated areas in the TSMD are scarce. I collected root and bulk zone soils associated with Andropogon virginicus from remediated and non-remediated sites in Webb City, MO. I used 16S rRNA gene amplicon sequencing to evaluate the bacterial …

Synthesis And Characterization Of The New G3 Family Of Organoantimony(V) Cyanoximates, Thao Trang Phan

Graduate Theses/Dissertations

Bacterial infections pose a serious threat to humans by developing resistance, rendering antibiotics ineffective. Of the 12 antibiotics recently approved since 2017, 10 belong to an already existing class. Various resistance mechanisms, such as reduced drug uptake, active efflux, drug inactivation, and target modification, can significantly reduce the efficacy of entire classes of antibiotics. Discovering novel strategies to overcome diverse mechanisms of resistance and improve therapeutic efficacy is in high demand. Inorganic compounds with organic ligands (both complexes and organometallics) represent a new class of compounds against which antimicrobial resistance has not yet been established. Recently, we discovered two series …

Handbook On Motion Practice, Katrin Rowan, Nan Haynes

Books

A guide for students in a clinical setting or any practice-oriented course in writing civil motions. The handbook covers major motion types, giving practical instruction on what such motions are intended to accomplish, when to file, and a wealth of information on not only the proper form of a written motion, but how to present them in the most effective manner. There is an extensive set of exercises to reinforce a student's mastery of motion practice.

Adapting To Uncertainty: Effects Of Environmental Instability On Zebrafish Behaviour, Britney Sekulovski

Theses and Dissertations (Comprehensive)

This thesis addresses how animals cope with unpredictability by testing how environmental stability changes the behaviour of zebrafish (Danio rerio) in two complementary experiments. In Experiment 1, fish lived for three months in either a Dynamic environment (water temperature, feeding times, habitat complexity, group size, and membership fluctuated) or a Stable environment (all factors constant). Across seven behavioural assays, measuring individual behavioural differences, collective movement, social memory, and information use, Dynamic condition fish were found to be more sensitive to social cues and more likely to conform to recent social information, independent of the quality of the information …

The Effects Of Environmental Complexity On Brain Development And Personality Expression In Western Hognose Snakes, Gokulan Nagabaskaran

Theses and Dissertations (Comprehensive)

There is growing interest in snake cognition, personality, and welfare as more snakes are kept as pets, yet little research has been conducted. The effects of enrichment and environmental factors have been well documented in other taxa, and recent evidence suggests that snakes may benefit in similar ways. This dissertation investigated the impact of environmental and social enrichment on personality expression, personality stability, and brain development. Western hognose snakes (Heterodon nasicus) were used as the model species, as they are a popular choice in the pet trade. This allows the research to be readily translatable to husbandry practices of many …

Minority Stress And Drug Use Among 2slgbtq+ Canadians, Robert Chin-See, Todd Coleman

Theses and Dissertations (Comprehensive)

Background: Several social and environmental factors influence drug use behaviors and contribute to frequent drug use among Two-Spirit, Lesbian, Gay, Bisexual, Transgender, Queer, and other (2SLGBTQ+) individuals. The purpose of the current study was to examine the relationship between the minority stress, drug use, and other socio-ecological factors.

Methods: This study employed structural equation modelling on data (2021—2022) from a nationally representative pan-Canadian survey (N = 1542) on 2SLGBTQ+ health to examine the association between minority stress, drug use, and relevant socio-ecological predictors. A separate mediation analysis was conducted and controlled for socio-demographic characteristics.

Results: SEM results showed parsimonious fit …

Exploring Parent-Child Reminiscing Style And Internal-State Talk When Discussing Positive And Negative Shared Events, Komal Verma Miss.

Theses and Dissertations (Comprehensive)

Conversations between parents and children about past events play a critical role in children’s social, emotional, and cognitive development. Parents scaffold their children in learning to recount details of their autobiographical memories by creating a space to reflect on internal states, specifically emotions and cognitions. Parents with an ‘elaborative’ reminiscing style are responsive to children’s utterances and ask open-ended questions (e.g., What do you remember about...?). Parents who are less ‘elaborative’ typically ask narrow questions like Did you like it?” that do not encourage conversation. Children whose parents use an elaborative reminiscing style have children who produce the most detailed …

Variables Related To School Readiness Among Canadian Children With Attention Deficit Hyperactivity Disorder Symptomology, Carlye Brokl

Theses and Dissertations (Comprehensive)

Children with attention deficit hyperactivity disorder (ADHD) symptoms face challenges academically, behaviourally, and socioemotionally at entry to formal education. Yet, these symptoms are rarely investigated prior to school entry, reducing the time that parents can prepare by learning about the disorder, scaffolding their children’s skills, and mediating the risk of long-lasting consequences related to unpreparedness for school. Within the current study, we aimed to uncover specific skills and elements within children’s environments which may be targeted for intervention prior to entering formal education. More specifically, we examined the relationship between the home literacy environment (HLE), mental-state understanding, ADHD symptomology, and …

Children's Peer Selection In Stem: The Influence Of Gender, Ethnicity, And Disability, Meagan Girard, Kim P. Roberts

Theses and Dissertations (Comprehensive)

The present study examined how children’s peer selection in STEM (science, technology, engineering, and mathematics) may be influenced by gender, ethnicity, and physical disability. Sixty-four children (ages 6-12) from elementary schools in Southwestern Ontario completed three tasks: a simulated peer selection task, an attribution of ability task, and a stereotype belief questionnaire. In the peer selection task, participants were repeatedly asked to select one peer from a set of AI-generated photographs showing children who differed by gender (male, female), ethnicity (White, Black, East Asian), and physical disability status (able-bodied user vs. nondisabled). The Peer Selection Task was based on the …

Investigating The Impact Of Winter Exposure To Natural Environments On Perceived Health And Well-Being Using Geographic Ecological Momentary Assessment: A Case Study At Arrowhead Provincial Park, Faith M. Laing

Theses and Dissertations (Comprehensive)

This study examined how winter exposure to specific natural environments influenced perceived health and well-being outcomes using Geographic Ecological Momentary Assessment (GEMA) in Arrowhead Provincial Park. Studies performed in the wintertime are limited, as is our understanding of how specific park features and/or activities impact health and well-being. To address this, GEMA was used with a video component to capture participants’ real-time experience and emotional responses in specific park locations defined by polygon boundaries. Two surveys were administered through participants mobile devices, one being an in-situ engagement survey triggered by entering a bounded location, which included a video and …

Religious And Spiritual Struggles: The Stories Of Nigerian, Immigrant, Christian Women In Waterloo Region, Halima D. Fuller

Theses and Dissertations (Comprehensive)

ABSTRACT This research investigates religious and spiritual struggles among Nigerian, immigrant, Christian women in Waterloo Region. Twelve women settled in the region for six months to 11 years participated in the study. Qualitative methodology, narrative inquiry, and a storytelling paradigm informed the research. Semi-structured, in-depth interview questions were used to explore the experiences of religious and spiritual struggles. A meticulous review identifies a scarcity of literature on religious and spiritual struggles in the context of immigration. However, immigration challenges such as language barriers, precarious employment, and mental health issues are well-documented (Bauder, 2012; Beiser & Hou, 2016; Berry et al., …

Science Fiction Cinema And The Technological Sublime: Spectacle And The Infinite From Early Cinema To Digital, David Jackson Dr.

Theses and Dissertations (Comprehensive)

This dissertation examines how science fiction cinema constructs and reimagines the technological sublime in the twentieth century: the experience of awe, terror, and admiration provoked by human-made power and scale. Drawing on the philosophical foundations of the sublime in Edmund Burke and Immanuel Kant and extending through Leo Marx’s and David E. Nye’s theorization of the technological sublime, I propose an aesthetic mode in which representation inflected with affect translates technological spectacle into examinations of humanity’s role and agency in the face of overwhelming technologized worlds and in some cases, even the universe itself.

Through three distinct historical periods …

Implementation Of A 3-Dimensional Hydrodynamic Numerical Model On A Large Northern Lake, Kirin Lorente

Theses and Dissertations (Comprehensive)

Climate change is impacting high latitude regions disproportionately more than those at a lower latitude. With polar lakes being highly sensitive to changes in the climate, shifts in lake ice dynamics and hydrodynamics are indicators of such changes in regional and global climates. These changes impact future seasons in a positive feedback loop, where changes in winter ice cover impact open water nutrients levels and lake thermal structure. This highlights the importance for long-term monitoring. Despite the abundance of lakes distributed across Northern Canada, there has been limited research conducted on these sentinels of climate change.

Specifically, Great Bear Lake …

Autism And Homelessness: An Intersectional Case Study In Kitchener-Waterloo, Ontario, Nicole J. Mcdonald

Theses and Dissertations (Comprehensive)

Homelessness is a growing crisis in Canada, with literature suggesting autistic traits as over-represented within this population. Literature addressing intersectional experiences of autism is emerging, however there are gaps in the research surrounding intersectional experiences of autism and homelessness. Research suggests that autistic individuals may be more vulnerable to experiencing homelessness and face difficulties in exiting homelessness. This qualitative case study utilizes a Disability Justice framework to explore intersectional autistic experiences of homelessness, social service usage, and suggests recommendations on improving support for autistic individuals at risk of and experiencing homelessness. Four autistic participants with experience of homelessness and accessing …

A Contribution To Constructing A Theory And Model Of Social Work Leadership, Cheri Darlene Bilitz

Theses and Dissertations (Comprehensive)

Few schools of social work provide formal leadership education and training for emerging social workers—the research topic under exploration was how social work leaders constructed their leadership style. The purpose of the study was to develop a model of social work leadership through understanding leaders’ journeys into leadership and the contextual factors that shaped their leadership. Participants shared the qualities they believed were paramount for leading today and into the future. Seeing schools of social work as leadership incubators for emerging social workers, participants shared their suggestions for scaffolded leadership curriculum. The methodological approach for this research study was constructivist …

Geovig And Purevig: Geometry-Aware Architectures For Efficient Computer Vision, Omar Ismail

Theses and Dissertations (Comprehensive)

Deploying deep learning models for medical image analysis on mobile devices requires a balance between inference latency, memory footprint, and delineating anatomical boundaries with high accuracy. While Convolutional Neural Networks (CNNs) and mobile Vision Transformers (ViTs) offer efficiency, they often struggle to model the irregular, non-local geometric structures inherent in biological tissues without incurring prohibitive computational costs. In this thesis, we introduce GeoViG (Geometric Vision Graph), an architecture that bridges the gap between efficient grid-based processing and explicit Geometric Deep Learning. GeoViG introduces a novel transition from high-resolution pixel grids to low-resolution dynamic graphs via a SpreadEdgePool operator, a geometry-aware …

A Novel Federated Llm Framework For Distributed Traffic Modelling In Intelligent Transportation Systems, Seerat Kaur

Theses and Dissertations (Comprehensive)

Intelligent transportation systems (ITS) depend on accurate traffic prediction to support congestion management, infrastructure planning, and real-time operational decisions. Despite substantial progress in data-driven forecasting, several challenges continue to limit practical deployment: traffic data is distributed across independent regional authorities, making centralized aggregation infeasible, standard federated aggregation strategies ignore traffic-specific characteristics that meaningfully affect model quality, and existing models produce only numerical outputs without interpretable reasoning that urban planners can act upon. This thesis addresses these challenges through four contributions that collectively advance privacy-preserving, explainable, and scalable traffic forecasting.

The first contribution provides a systematic review of 129 peer-reviewed publications, …

Acid-Base Regulation Mechanisms In The West African Lungfish Protopterus Annectens: An Investigation Into The Role Of The Sodium Proton Exchanger (Nhe), Victor H. Q. Pham-Ho Msc

Theses and Dissertations (Comprehensive)

The lungfish possesses a primitive lung and underdeveloped gills, making use of bimodal respiration. Like other freshwater fishes they must regulate ion- and acid-base equilibrium through active ion uptake (driven by pumps and ion transporters), albeit with challenges due to their underdeveloped gills. My thesis aimed to elucidate the role of the sodium proton exchangers (NHE), encoded by the genes slc9a1/nhe1, slc9a2/nhe2 and slc9a3/nhe3, which are hypothesized to contribute towards acid-base regulation. Pharmacologically, amiloride, a sodium-transport inhibitor, and 5-(N-Ethyl N-isopropyl)-Amiloride (EIPA), an NHE specific inhibitor, affected whole-animal titratable acidity and ammonia fluxes, supporting a physiological function of the NHE. Next, …

Intelligent Electric Vehicle Routing For Goods Delivery Under Real-Time Traffic Conditions: A Comparative Framework For Modular Battery Swapping And Dynamic Wireless Charging, Ranjit Jakharabhai Odedra

Theses and Dissertations (Comprehensive)

Electric vehicles (EVs) are becoming central to sustainable and intelligent transportation systems, particularly in urban logistics, where reducing emissions, congestion, and operating inefficiencies is increasingly important. Despite their environmental advantages, the large-scale deployment of EVs in delivery operations remains constrained by limited driving range, time-consuming energy replenishment, and the difficulty of making routing decisions under dynamic traffic and load-dependent energy consumption. Addressing these challenges is essential for improving the practicality and reliability of EV-based freight transportation.

This thesis investigates optimization frameworks for EV routing in urban delivery systems by studying two complementary energy replenishment strategies: modular battery segment swapping and …

Youth Perspectives On Developing A Sustainable Food Future In Sambaa K’E Nwt., Danielle Elizabeth Bayne Ms

Theses and Dissertations (Comprehensive)

Food systems in Northern Indigenous communities are shaped by complex and interconnected social, environmental, economic, and political forces that determine how food is accessed, practiced, and governed. Indigenous food systems are deeply rooted in Land-based practices and relationships that support cultural continuity and intergenerational knowledge transfer. However, these systems have been profoundly disrupted by ongoing colonial structures that restrict access to and devalue Indigenous Knowledge and alter harvesting practices. Climate change further intensifies challenges related to traditional food access by altering wildlife behaviour, shifting seasonal patterns and reducing the safety and reliability of traditional harvesting territories. In response, many Northern …

Assessing Dissolved Organic Matter Sources And Dynamics In Urban Stormwater: Implications For Greenhouse Gases, Harper W. Schmalz

Theses and Dissertations (Comprehensive)

Stormwater management ponds (SWMPs) are important aspects of land-use planning and increasingly recognized as active sites of biogeochemical processing that influence carbon cycling; however, little research has investigated the controls on dissolved organic and dissolved inorganic carbon (DOC and DIC) within these systems. This thesis examined the processing and transformations of dissolved carbon between three compartments to support the development of a greenhouse gas (GHG) box-model for urban stormwater ponds, including SWMP sediment, surface water, and vegetation. The objective of this thesis was to assess the biogeochemical processes that govern the rate and transformation of DOC and DIC between these …

A Constructivist Grounded Study: At The Intersection Of Religion And Intimate Partner Violence In The Context Of An Ultra-Orthodox Jewish Community, Lauren Kalvari

Theses and Dissertations (Comprehensive)

This constructivist grounded theory study, informed by a critical intersectional lens and guided by symbolic interactionist theory, explored how Ultra-Orthodox Jewish women experience and navigate intimate partner violence (IPV) within their religious and community contexts. Ten participants, recruited through purposive and theoretical sampling, were separated or divorced from abusive partners for at least eight months and had engaged in psychotherapy, allowing for retrospective meaning-making. Each participant completed one to three in-depth interviews on IPV, community responses, spiritual conflict, and recovery. Data collection and analysis were conducted concurrently using Charmaz’s iterative constructivist grounded theory approach, which included initial, focused, and theoretical …

Picturing Your Goals: Examining Imagery Perspective And Self-Concordance In Goal Motivation, Cana J. Reuber

Theses and Dissertations (Comprehensive)

Mental imagery is often used as a strategy to increase motivation and support goal pursuit, but it remains unclear when different forms of imagery are most effective. Prior work suggests that adopting a third-person imagery perspective may enhance goal striving by promoting more abstract, identity-relevant processing. In line with this work, we predicted that third-person imagery would be most beneficial for self-concordant goals. The present research tested this prediction across three studies. In Study 1 (N = 273), participants identified a personal goal, visualized themselves pursuing and attaining it from either a first- or third-person perspective, and reported their …

Investigation Of Mercury Bioaccessibility In Subsistence Fishes From The Canadian Subarctic, Kiran Mateo Sharma Mr

Theses and Dissertations (Comprehensive)

Fish consumption is the primary pathway for human exposure to methylmercury (MeHg), a global contaminant of concern known to cause adverse health effects. Fort Albany First Nation, a remote Indigenous community in northern Ontario that relies on fish for both subsistence and cultural practices, has expressed concern regarding the safety of local fish consumption. Community members and leaders have communicated several priorities for scientific research that are the foundation of this thesis. Specifically, consumers of wild-caught fish have asked how traditional cooking methods may affect mercury concentrations in fish, and how mercury concentrations in little-studied organs, such as liver and …

An Examination Of Speech Motor Control And Auditory Processing In Attention Deficit Hyperactivity Disorder (Adhd), Rita Bishai

Theses and Dissertations (Comprehensive)

Fluent speech production is achieved through a relative weighting of feedback and feedforward motor control systems. These systems are thought to be responsible for the online correction of vocal errors and initiating speech, respectively. The relative weighting of these motor control systems has been shown to differ under conditions of high attentional load and across individual differences in sensory acuity. However, research has yet to examine speech motor control in a population with clinical attentional and sensory processing differences, such as those with Attention-Deficit Hyperactivity Disorder (ADHD). The studies in this thesis aimed to examine how ADHD traits relate to …