Open Theses & Dissertations

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Now showing 1 - 20 of 2054

The Falls Island Collection: A report on a collection of late Maritime Archaic through Protohistoric period artifacts from Falls Island in Cobscook Bay, Maine.
(University of New Brunswick, 2025-02) Cummings, Joshua A.; Hrynick, M. Gabriel; Anderson, Arthur
Falls Island is located in Cobscook Bay, Maine, in the western Quoddy Region. Between the 1930s and 1950s, local avocational archaeologists John and Douglas Knapton visited the island and collected artifacts from eroding shell middens and intertidal zones. Their collection was donated to the Robert S Peabody Institute, where they are currently curated. I analyzed the artifacts using a culture-historical approach. The collection suggests an extensive period of occupation from the Late Maritime Archaic through Late Maritime Woodland periods (ca. 5500-550 cal BP). In this thesis I place the artifacts chronologically using typology from the Quoddy Region, the Atlantic Northeast, and New England. I also conducted a pedestrian survey of Falls Island, which revealed two remaining archaeological sites, and two eroded sites. This thesis uses collections research and pedestrian survey to analyze coastal archaeological sites in the Quoddy Region.
DGSim: A scalable and configurable framework for simulating energy consumption of household appliances
(University of New Brunswick, 2025-02) Addala, Bhavani Sai Prasad; Kent, Kenneth B.
We introduce DGSim, a flexible and scalable framework for simulating household energy consumption. Traditional energy simulation tools often struggle with configurability across diverse household types and scalability to urban and regional scales. First, we explore DGSim’s ability to adapt to different appliance configurations and household structures, allowing precise modeling of varied consumption patterns. Second, we implement a multi-faceted configurability approach, enabling detailed customization for appliances, usage patterns, and community demographics. Third, we enhance scalability with optimizations that support large-scale simulations involving millions of instances, allowing DGSim to model energy use across residential communities. Our evaluation demonstrates DGSim’s capability to provide insights for demand-side management, highlighting its benefits over existing simulation frameworks for both detailed and large-scale residential energy analysis.
“The Greatest Scoundrels in the Universe:” Haitian migrants, revolutionary contagion, and Jamaican migration law during the Haitian Revolution
(University of New Brunswick, 2025-02) Waters, Colin; Hunt-Kennedy, Stefanie
In 1791, the enslaved people of French Saint-Domingue revolted, leading to a thirteen-year revolutionary war. In the neighbouring British colony of Jamaica, slaveowners feared that revolutionary ideology would spread and inspire Jamaican bondspeople to revolt. Between 1791 and 1799, Jamaican lawmakers, who were themselves slaveowners, responded to the threat of revolutionary contagion through a series of laws known as the Alien and Foreign Slave Acts. The creation and development of these laws was also shaped by a long-standing political dispute between Jamaica and Great Britain over their respective privileges and powers and over the future of slavery. The legislation sought to limit the entry of Saint-Domingue migrants, including white slaveowners, free people of colour, and the enslaved, restrict their movements within Jamaica, and surveil them. These laws, unprecedented in their scope and severity, demonstrate the ways that Jamaican slaveowners drafted legislation to navigate colonial politics and perpetuate slavery.
Developing a hybrid actuated cable-driven parallel manipulator using a compact tape rod actuator
(University of New Brunswick, 2025-02) Sanford, Paul William; Antonio Carretero, Juan
Cable-driven parallel manipulators (CDPMs) are an active area of research due to their efficiency, speed, and range of workspace sizes. In this work, a parallel manipulator with hybrid actuation is developed to expand the capabilities of conventional CDPMs by adding a compact linear actuator. The linear actuator, which unlike cable actuators can push and pull, is created using three tape measures forming a rigid rod that can be spooled. The combined mechanism is controlled using position and force sensors for each of the four actuators. The mechanical design, control system, kinematics, and electronics are discussed. The cable and tape rod actuators were tested individually and as a manipulator with quasi-static loading. The control system and cable actuators were able to reliably apply compressive forces to the tape rod actuator, which experienced early fatigue and excessive wear.
Chasing the dream: Understanding the journey of Canadian high performance athletes, the nature of the challenges and the motivation to persevere
(University of New Brunswick, 2013-01) Allain, Monique; Morrison, William; Peterson, Patricia
The purpose of this study was to develop a better understanding o f the journeys of Canadian high performance athletes, specifically, their experiences of strain and social support in becoming and being a senior national team member, representing Canada at international events. Eleven Canadian high performance athletes shared their journeys while competing at the 2011 Pan American Games, held in October 2011 in Guadalajara. The research design employed a narrative inquiry approach, and included in-depth interviews that were conducted with participating athletes. The goal of this investigation was to give voice to the athletes, allowing them to share their stories. The process of interviewing and analyzing the athletes’ stories yielded a deeper understanding of how they drew upon internal and external resources in meeting core psychological needs associated with relatedness, competence and autonomy support. Based on the completed research, a five-step model for building athletes’ resiliency is proposed.
Evaluating asphalt mixture performance in New Brunswick: Defining baselines for volumetric design with performance verification
(University of New Brunswick, 2025-02) Biglari, Moein; Sanchez-Castillo, Xiomara
This study aimed to evaluate the asphalt mixtures used in New Brunswick to establish thresholds as a significant step toward adopting the Balanced Mix Design (BMD) approach. For this purpose, asphalt cores were extracted from six in-service pavement sections in the province. Additionally, two widely used mixtures in New Brunswick were produced and compacted in the laboratory. The Tensile Strength Ratio (TSR) test was conducted to evaluate the moisture susceptibility of the laboratory-prepared specimens. To assess the rutting potential of both cored and laboratory mixes at high temperatures, the Rapid Shear Rutting Test (Ideal RT) test and Hamburg Wheel Track Test (HWTT) test were utilized. The Indirect Tensile Asphalt Cracking Test (Ideal CT) test and Semicircular Bend (SCB) test were employed to investigate the fracture performance of mixes at intermediate and low temperatures, respectively. Finally, using road survey data collected by (Automatic Road Analyzer) ARAN, final thresholds were determined as acceptance criteria for the province of New Brunswick.
A system not their own: Investigating organizational barriers and facilitators to mental health care access among youth
(University of New Brunswick, 2025-02) Miller, David; Ronis, Scott
Onset of mental illness predominantly occurs in adolescence, with epidemiological trends continuing to show that youth represent the greatest comparative year-over-year increase in mental illness onset among age cohorts (Canadian Institute for Health Information, 2022; Raballo & Poletti, 2020). Despite being most likely to experience the onset of psychopathology, 40% of youth with a mental illness are unable to access appropriate supports (Canadian Institute for Health Information, 2015, 2022; Mental Health Commission of Canada, 2016). Barriers stem from constraints in the accessibility and availability of services and are exacerbated by youths’ positions within overarching care systems (de Haan et al., 2013, 2018; Gouliquer & Poulin, 2005). Youth face challenges related to their lack of autonomy, and they disproportionately rely on caregivers and providers for symptom identification and treatment adherence (Birleson & Vance, 2008; Iyer et al., 2015; Wittevrongel et al., 2024). Despite their reliance on adults, 60% of youth endorse receiving little support from others when accessing care (Canadian Institute for Health Information, 2022). As such, it is crucial to obtain youth perspectives to determine ways in which their limited agency affects help seeking in a primarily service-provider-controlled health system. Thirty-four semi-structured interviews were collected as part of the Atlantic Canada Children’s Effective Service Strategies Mental Health (ACCESS-MH) project (ACCESS-MH, 2014), a large-scale multi-site qualitative research project examining barriers and facilitators to mental health treatment among youth in Atlantic Canada. Interviews were analyzed using the Psycho-Social Ethnography of the Commonplaces (P-SEC) methodology to highlight the impact of systemic policies and protocols on youth mental health journeys. Complications to access stemming from provincial mental health policies or protocols were coded as “Organizational Moments” (OMs). Two OMs comprise individual manuscripts in this thesis to allow for in-depth analysis of specific complications, coping strategies, and schematic shifts encapsulating the way youth made sense of the barriers to care. Findings provide a contextual perspective of the unique barriers youth face that stem from stepped-care treatment models, standardized care approaches, and legal nonautonomy.
Beyond moral leadership: Edward H. Levi and the need for structural reform in the Attorney General’s office after Watergate
(University of New Brunswick, 2025-02) Purnell, Elizabeth; Corke, Sarah-Jane
In the aftermath of Watergate, President Gerald R. Ford nominated Dr. Edward H. Levi as Attorney General (AG) of the United States. Ford hoped Levi’s appointment would symbolize a new tradition of an independent AG. As the nation’s chief law officer and member of the Cabinet, the AG had become enormously influential since the position’s creation in 1789. However, politics and ambiguous language concerning the roles and responsibilities of the AG did much to undermine the AGs independence. Ford, hoping the AG’s character alone would restore the office’s integrity, sought an AG who embodied independence, integrity, and professionalism. This thesis argues that although Levi epitomized these three traits, they did not ensure his success in establishing long-lasting structural reforms necessary to insulate the position from politicization and secure a nonpartisan AG in perpetuity.
Leveraging bilingual dictionaries to learn word embeddings for low-resource languages
(University of New Brunswick, 2025-02) Bear, Diego; Cook, Paul
Word embeddings [33, 36] have been used to bolster the performance of natural language processing systems in a wide variety of tasks, including information retrieval [42] and machine translation [37]. However, approaches to learning word embeddings typically require large corpora of running text to learn high quality representations. For many languages, such resources are unavailable. This is the case for Wolastoqey and Mi’kmaq, two endangered low-resource Eastern Algonquian languages. As there exist no large corpora for Wolastoqey and Mi’kmaq, in this thesis, we leverage bilingual dictionaries to learn Wolastoqey and Mi’kmaq word embeddings by encoding their corresponding English definitions into vector representations using English word and sequence representation models. Specifically, we consider representations based on pretrained word2vec [33], RoBERTa [31], and sentence-RoBERTa [40] models, as well as, fine-tuned sentence-RoBERTa models [40]. We evaluate these embeddings in word prediction tasks focused on part-of-speech, animacy, and transitivity; semantic clustering; and reverse dictionary search. We additionally construct word embeddings for higher-resource languages — English, German and Spanish — using our methods and evaluate our embeddings on existing word-similarity datasets. Our findings indicate that our word embedding methods can be used to produce meaningful vector representations for low-resource languages such as Wolastoqey and Mi’kmaq and for higher-resource languages.
Surrogate-based multi-objective optimization of modulated wave laser powder bed fusion using active learning: Balancing time and quality
(University of New Brunswick, 2025-02) McCarthy, Thomas; Aranas Jr., Clodualdo
Additive manufacturing, and more specifically laser powder bed fusion (LPBF), complements conventional manufacturing by producing a low volume of highly complex functional metallic components. The mode of laser emission, either continuous (c-LPBF) or modulated (m-LPBF), has a pronounced impact on the resulting component. Although both have merits, the c-LPBF process dominates commercial machines and academic efforts. To promote further exploration of m-LPBF, which has the potential to reduce defects and enhance microstructural control, the process must strike a balance between component quality and the industry’s demand for increased production. In this work, a multi-objective optimization framework was adopted to balance time and quality of m-LPBF produced Ti-6Al-4V as a function of key processing parameters. Lacking an analytical model, Bayesian inference of Gaussian process regression was utilized to relate laser power, exposure time, point distance, and hatch spacing to the as-built relative density, serving as a proxy for quality, while batch active learning efficiently sampled the design space. In combination, this model accurately captured the relationship in a modest number of experiments and, in conjunction with the application of non-dominated sorting genetic algorithm II, was able to determine a non-dominated set of solutions approximating the Pareto front. Despite the model's accuracy, the current work highlights the need for a sufficiently large data set to accurately reflect the underlying mechanisms occurring in the m-LPBF process.
The spatial and trophic ecology of invasive Largemouth Bass (Micropterus salmoides) in the Wolastoq | Saint John River
(University of New Brunswick, 2025-02) Culberson, Abigale; Curry, R. Allen; Harrison, Philip
When invasive species are introduced, they have negative impacts on the local system, including reducing populations of endemic species and drastically changing the ecosystem around them. As a recently introduced species, Largemouth Bass (Micropterus salmoides) are a growing concern in the Wolastoq | Saint John River, New Brunswick. Following their colonization, this master’s project began to investigate the trophic and spatial ecology of Largemouth Bass early in their colonization phase in a novel system at their northeastern range extent in North America. The results of this study suggest that Largemouth Bass exhibit increased predation and competition on local species and are at high risk of spread within the system. Given these results, the threat of Largemouth Bass within the Wolastoq | Saint John River system is high. This study should act as a baseline to compare to any future work and risk assessment.
A parametric study of a tidal turbine hub retrofit’s influence on power generation and thrust
(University of New Brunswick, 2025-02) Corbett, Finley; Jeans, Tiger; Gerber, Andrew
For efficient tidal energy extraction using traditional horizontal axis turbines, it is desirable to maximize electrical power output and minimize thrust loads. This research addresses both factors by establishing a workflow to parametrically investigate the influence a co-rotating hub retrofit has on the hydrodynamics of an existing horizontal axis tidal turbine using Computations Fluid Dynamics (CFD). Within the parametric space of the 21 high-fidelity simulations performed, it was concluded that the net effect of the retrofit did not improve power generation, but reduced thrust by a maximum of 0.21%. While isolated torque imparted on the primary blades increased, an added counter-acting moment directly caused by the retrofit neutralized this effect. Primary blade load influence after the retrofit was added was caused by the retrofit tip vortex, the modification of the primary blade relative flow angles, and the increase in horseshoe vortex strength at the root to hub junction.
Borderline personality vulnerabilities for intimate partner violence perpetration in a non-forensic sample: Developing a typology and theoretical model
(University of New Brunswick, 2025-02) Doyle, Jessie Nicole; Campbell, Mary Ann
Research demonstrates that intimate partner violence (IPV) perpetrators are heterogeneous (Corvo & Johnson, 2013). Borderline personality disorder, a mental health condition reflecting a pervasive pattern of interpersonal and identity dysfunction, emotion dysregulation, and impulsivity (APA, 2013), has often been recognized among IPV perpetrators (Spencer et al., 2019). Nonetheless, not all IPV perpetrators have BPD traits, nor do all people with BPD traits perpetrate IPV. Better understanding a ‘borderline subtype’ of IPV perpetrators may help discern which BPD features are predictive of IPV behaviours (physical, psychological, sexual). The current research utilized online recruitment strategies to: (1) identify latent profiles of self-report BPD features, insecure attachment, and anxiety sensitivity (AS) among a non-forensic sample; (2) distinguish latent profiles on their reported IPV behaviours; (3) test the explanatory value of attachment dimensions and AS in the BPD-IPV pathway; and (4) investigate the validity of BPD features over and above traditional criminogenic risk factors in predicting IPV behaviours. From the final sample of community-based members (N = 451, Mage = 31.98, 62.7% men), two profiles emerged via latent profile analysis: (1) insecure attachment-specific (IAS, n = 90) and (2) mixed borderline features (MBF, n = 361). MANOVAs revealed that the MBF profile endorsed significantly more frequent and severe IPV behaviours and criminogenic risk factors. Structural equation modelling demonstrated that insecure attachment and AS partially mediated relations between BPD and IPV. Hierarchical regression analyses and canonical correlation analyses indicated that BPD features and traditional criminogenic risk factors each have incremental validity in predicting IPV behaviours. Correctional implications include adding BPD features to existing IPV risk assessment tools. Clinically, results corroborate the notion that addressing heterogeneity in IPV offenders is important for tailoring evidence-based interventions to the unique needs of offenders (Butters et al., 2021). Whereas insecure attachment-specific offenders might benefit from attachment-based or emotionally-focused couples therapy, mixed borderline features offenders would likely require interventions that focus on enhancing emotion regulation (e.g., dialectical behaviour therapy). Overall, the present findings support the need to tailor IPV interventions, and continue investigating the role of BPD features in IPV behaviours to maximize the utility of current risk assessment tools.
Feasibility of producing non-structural wood products using trembling aspen lumber
(University of New Brunswick, 2025-01) Zhang, Mengyuan; Gong, Meng; Chui, Ying-Hei
Trembling aspen (Populus tremuloides) is abundant in Canada but underutilized in non-structural solid wood products. This study was aimed at evaluating the feasibility of using aspen lumber to produce flooring, moulding, and siding. The shrinkage, surface roughness, and wettability of aspen wood were tested. The surface hardness, screw withdrawal resistance, colour change, and dimensional stability of three products fabricated were examined. The wood yield of each product was analyzed. It was found that aspen showed superior machinability and wettability to silver maple and yellow poplar. Aspen flooring had a Brinell hardness of 13.47 MPa, 60% lower than silver maple. Aspen moulding exhibited a screw withdrawal resistance of 23.42 MPa, 15% higher than eastern white pine. Aspen siding showed comparable colour and dimensional stability to spruce-pine-fir wood. The aspen wood yields were estimated to be 38.25%, 25.4%, and 49.2% for flooring, moulding, and siding, suggesting its potential for non-structural applications.
Case studies on the life cycle assessment of lumber production and of tall wood buildings
(University of New Brunswick, 2025-01) Zahabi, Nadia; Gong, Meng; Gu, Hongmei
Mass timber provides a low-carbon alternative to steel and concrete, reducing global warming potential (GWP) and non-renewable energy use while acting as a carbon sink. Life cycle assessment (LCA) evaluates environmental impacts, supporting sustainable construction practices. This research includes three LCA case studies. The first examined softwood lumber production in New Brunswick, Canada, with emissions of 43 kg CO₂ eq/m³, relying on 58% renewable energy from woody biomass during kiln drying. The second analyzed hardwood lumber, emitting 41 kg CO₂ eq/m³ up to sawing, using 98% non-renewable grid energy. Both softwood and hardwood offset their emissions with stored carbon, achieving negative GWP. The third study compared cradle-to-grave impacts of hybrid mass timber-steel, full mass timber, steel, and concrete designs in the Bakers Place project, USA. Mass timber significantly reduced GWP and non-renewable energy but showed higher acidification and eutrophication impacts due to transportation and landfill decomposition.
Exploiting temporal dynamics to improve the robustness of continuous myoelectric control
(University of New Brunswick, 2025-01) Tallam Puranam Raghu, Shriram; Scheme, Erik J.; MacIsaac, Dawn T.
Myoelectric control based on Surface electromyography pattern recognition (sEMG-PR) offers intuitive and dexterous control of powered prostheses for people with limb differences. However, conventional sEMG-PR systems often struggle with transitions between movements, impacting online usability. In this thesis, we investigated these transition-specific challenges and proposed novel approaches to enhance the performance and user experience of sEMG-PR systems. We first established a comprehensive framework for evaluating classifier performance during transitions, incorporating transition-specific metrics and continuous dynamic datasets. This framework represents an improvement over conventional evaluation methods, which often focus primarily on steady-state performance and neglect transitions. Our analysis, utilizing this enhanced framework, revealed that classifiers, even with similar steady-state performance, can differ substantially in their ability to handle transitions. This finding underscores the limitations of conventional evaluation methods. Next, we systematically investigated various error-mitigation strategies, including existing and novel post-processing techniques. While some techniques showed promise, particularly those based on rejection, our findings suggest that relying solely on post-hoc error correction may not be sufficient to address the challenges of transitions effectively. Finally, we explored incorporating continuous dynamic data, inclusive of transitions, into the training process. Our results demonstrated the advantages of leveraging Long Short-Term Memory (LSTM) networks, which can effectively capture the dynamic nature of transitions. Furthermore, we pioneered the use of self-supervised learning for sEMG-PR, and demonstrated its effectiveness in learning meaningful and robust representations from unlabeled continuous dynamic data, leading to enhanced performance both offline and online. Our findings underscore the crucial role of temporal information, dynamic training data, and appropriate model selection, particularly temporal models like LSTMs, in achieving robust and reliable sEMG-PR based myoelectric control. The proposed approaches have the potential to significantly enhance the usability and effectiveness of these systems, paving the way for more intuitive and user-friendly prosthetic devices.
Learning dynamic regimes of event-based substructures in EEG data using Graph Kernel Koopman Embedding
(University of New Brunswick, 2025-01) Nagawara Muralinath, Rashmi; Mahanti, Prabhat K.
Understanding brain activity requires analyzing EEG data, which is challenging due to the high noise levels, non-linearity, non-stationarity, and individual variability. This thesis introduces a novel methodology using Graph Kernel Koopman Embedding (GKKE) methodology by representing time-evolving brain connectivity as low-dimensional, meta-stable regimes. The study focuses on two critical applications: detecting epileptic seizures (CHB-MIT dataset) and assessing cognitive workload (Cognitive Mental Workload dataset). This research attempts to classify cognitive and neurological states using various combinations of connectivity measures, graph kernels, and classifiers. The results demonstrate that the method has a good classification accuracy of above 85% for both datasets, thus demonstrating its potential to identify intricate patterns. The suggested method involves preprocessing the raw EEG data through which the connectivity matrix is obtained by calculating correlation coefficients and generating gram matrices. Next, we use kernel PCA to simplify the graph features by reducing their dimensions. After that, we test how well they work with machine learning classifiers.
Genetic variation in adventitious rooting, seed germination, and berry phenolic content of black elderberry (Sambucus canadensis) in New Brunswick
(University of New Brunswick, 2025-01) Germaine, Tanya Rae; Sacobie, Charles; Smith, Ron
Black elderberry (Sambucus canadensis), a North American shrub valued for its ecological and medicinal properties, remains underexplored compared to its European counterpart, Sambucus nigra. This study investigates genetic variation in seed germination, adventitious rooting, and phenolic content (chlorogenic acid and rutin) among wild S. canadensis populations in New Brunswick, Canada. Ten populations from diverse biogeographic zones were sampled. Germination success varied significantly (59%–78%), with coastal populations germinating faster. Phenolic concentrations ranged widely (chlorogenic acid: 487–1825 ng; rutin: 884–2404 ng), showing strong correlation (β = 0.735, p < 0.001). Root development showed limited site variability and no correlation with plant size. Results highlight substantial genetic and phenotypic diversity, underscoring the species’ potential for ecological restoration, sustainable agriculture, and bioactive compound production. This research informs population selection for adaptability and enhanced bioactive compound production.
Explainable decision-making framework concealed in graph statistical models of chemistry
(University of New Brunswick, 2025-01) El-Samman, Amer; De Baerdemacker, Stijn
Recent advancements in probabilistic models in chemistry have unlocked ground-breaking potential, yet these innovations come with heightened caution. Decisions made by techniques, such as neural network models, are seldom fully understood, even by developers themselves, making it difficult to integrate these models into an established scientific discourse. Nevertheless, their use remains widespread and likely to increase, as they generate predictions that rival or surpass traditional chemical models in efficiency. This great potential combined with a lack of explainability has placed these models under increasing scrutiny, leading to the field of explainable artificial intelligence. This thesis investigates graph probabilistic models of chemistry, particularly graph neural nets, to develop an explanatory framework of decision-making that can be quantitatively blueprinted and replicated. We probe the cryptic high-dimensional nature of the feature space of these models, compacting their dimensions to elucidate a decision-making framework based on the molecular substructures of chemistry. We then demonstrate that the decision-making framework of these models is organized around chemical formula language/syntax from which the hidden framework can be replicated, while also providing a novel way of exploring reactions. Finally, we show the completeness of these models by transferring their capabilities to solve a wide range of chemical problems, from predicting pKa values and NMR data to modeling electron density and solubility.
The role of landscape features on the distribution of freshwater mussels in the Lower Wolastoq, New Brunswick
(University of New Brunswick, 2025-01) Cusack, Sarah; Gray, Michelle
Freshwater mussels provide habitat, structural stream bed support, nutrient cycling and act as an indication of ecosystem health. There are eight species in the lower Wolastoq: Alewife Floater (Utterbackiana implicata), Eastern Floater (Pyganodon cataracta), Triangle Floater (Alasmidonta undulata), Eastern Elliptio (Elliptio complanata), Eastern Lampmussel (Lampsilis radiata), Tidewater Mucket (Atlanticoncha ochracea), Eastern Pearlshell (Margaritifera margaritifera), and Yellow Lampmussel (Lampsilis cariosa). This study assessed the distribution of available habitat for in relation to the landscape controls producing differences in regional energetic gradients. Species-specific habitat distribution models were validated using snorkel surveys at 34 sites. This study determined that landscape features can be employed to identify suitable habitat across the Wolastoq. Suitable habitat characteristics did not always guarantee rare species presence but identified areas for future conservation work. Lower-gradient habitats supported higher species richness, while higher gradient habitats hosted fewer specialist species. Sediment characterization revealed species-specific preferences for depositional or erosional habitat.

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