Open Theses & Dissertations

Permanent URI for this collection

https://unbscholar.lib.unb.ca/handle/1882/12778

Browse

Now showing 1 - 20 of 2032

Patients’ and families’ perceptions of privacy of health information and data sharing in New Brunswick
(University of New Brunswick, 2024-12) Seeley, Joanna; Balcolm, Sarah; Durepos, Pam
Information sharing between different interoperable health databases is called health information exchange (HIE). Although the HIE of personal health information (PHI) can improve patient safety for Canadians, some provinces do not disclose PHI about patient safety incidents with federal and pan-Canadian patient safety surveillance systems. A frequently cited barrier to HIE by healthcare organizations is patients’ and families’ concerns for their privacy. This study, guided by qualitative descriptive design, explored patients’ and families’ perceptions of privacy and the secondary use of PHI collected, used, disclosed, and retained on patient safety events. Participants identified privacy criteria, conditions for the access of PHI, types of data for HIE, and the purpose of HIE. There is a significant opportunity for data custodians to use the research findings to create a patient-centric framework for the HIE of PHI.
Development of deep learning-based classification and unsupervised clustering methods for mineral mapping using remotely sensed hyperspectral data
(University of New Brunswick, 2024-12) Peyghambari, Sima; Zhang, Yun
Hyperspectral remotely sensed imagery is a powerful tool for mineral mapping. It captures detailed spectral information across hundreds of contiguous and narrow spectral bands to enable precise identification of various geological materials. Conventional methods mainly use shallow spectral absorption features to discriminate minerals and cannot extract their important spectral information. However, traditional methods face significant challenges in effectively handling hyperspectral data's high dimensionality, nonlinear spectral features, and low signal-to-noise ratio (SNR). These challenges limit the accuracy of traditional machine-learning algorithms in mapping the spectral variations of minerals. This PhD research addresses these limitations through a comprehensive literature review and the development of new methods. It has resulted in two published journal papers and one submitted journal paper, presented across three chapters of this dissertation. The third chapter of this dissertation (published review paper) provides an updated systematic overview of hyperspectral missions, diagnostic minerals' spectral properties, and various geologic information extraction techniques, including preprocessing, dimension reduction, endmember retrieval, and important image classification methods from spaceborne/airborne HSI. It evaluates the advantages and limitations of the existing conventional methods of processing HSIs with the aim of geological mapping. The fourth chapter (published paper) aims to improve the accuracy of spectral-spatial deep learning extractors in classifying HSI datasets. While traditional deep learning methods such as fully connected neural networks (FCNN), convolutional neural networks (CNNs), and hybrid CNNs like mixed convolutions and covariance pooling (MCNN-CP) algorithms have shown promise, they face limitations in robustness and accuracy. This proposes an integrated 1D, 2D, and 3D CNN architecture to enhance the capability of spectral-spatial extractors, significantly improving classification accuracy and resilience. The fifth chapter (submitted) explores deep learning-based clustering methods for unsupervised mineral mapping, which are valuable in remote areas where ground truth data is scarce. These methods leverage HSIs' high-dimensional and redundant spectral features, using advanced clustering techniques to generate accurate mineral maps without requiring extensive labelled data. This research proposes a hybrid 3D-2D convolutional autoencoder to capture HSI's spatial and spectral diversity. The anticipated outcomes include enhanced accuracy and computational efficiency, ultimately improving the utility of HSI for geological studies and resource exploration.
foreglow
(University of New Brunswick, 2024-12) Johnson, Colin Uriah; Crawford, Lucas; Sinclair, Sue
foreglow is a long lyric poem investigating the intricate and often mercurial interplay between poetics, queer theory, and utopian potentiality. Over nine multi-register, hybrid genre sections, a menagerie of domestic and mundane scenes frame its critique of the human desire to impose order while acknowledging (and, yes, even longing for) the existential ambiguity that follows a collapse of spatiotemporal certainty. The poem resists stable narratives about desire as individual and collective histories intertwine with environmental and temporal dislocation, dissolving boundaries between internal reflection and external reality. The critical introduction to foreglow posits that lyric poetry can function as a dynamic, ritualistic site of encounter that challenges traditional narrative authority and interprets individual subjectivity through a critical lens. Drawing on Jonathan Culler's concept of the "iterable now" and Anne Carson's insights on erotic paradox, the introduction examines how lyric poetry creates a temporality that simultaneously acknowledges and resists discrete ontological categories such as presence and absence. By integrating José Esteban Muñoz's notion of queer futurity, the project highlights how aesthetic practice can offer alternative modes of temporality and subjectivity that transcend linear narratives. Through a close reading of foreglow and its graphic codes, as well as comparative analyses with poets such as John Wieners and Cody-Rose Clevidence, the dissertation investigates how disidentificatory practices and the subversion of conventional poetics facilitate new forms of relationality and pleasure. The final section of the introduction considers Lisa Robertson's influence on foreglow, emphasizing how unconventional approaches to temporality and language contribute to the poem's exploration of utopian potentialities. This research underscores the potential of lyric poetry to both reflect and reshape the experiences of desire, subjectivity, and community.
The “drive-through province” problem: New Brunswick’s transit space tourism, 1929-1999
(University of New Brunswick, 2024-12) Cox, Sean Christopher; Mullally, Sasha
This dissertation examines New Brunswick’s multi-decade change from a destination space to a transit space for modern leisure motorists. New Brunswick’s recreational reputation as a rustic sporting destination was originally manufactured by provincial authorities in the late 19th and early 20th century. This successful marketing scheme failed to keep pace with popular tourism trends, however, especially as automobility reshaped consumer experiences of travel time and relationships to destination spaces. Modernizing automobility and expanding road systems compressed time-space across North America, and the small province of New Brunswick struggled to maintain a competitive tourism identity. In response to these forces, aggressive provincial investments to improve infrastructure and launch marketing campaigns reframed the province as an attractive location easily reached and enjoyed by car. While proactive and innovative, many of these efforts only temporarily relieved what I describe as the province’s “transit space problem.” New Brunswick’s complex tourism history has been overshadowed by the perception that it is largely a “drive-through province.” Yet, archival evidence demonstrates a long-developing transit space problem was neither inevitable nor passively accepted. As a contribution to the historiography of tourism, this dissertation captures a rare transit space case-study applicable beyond Atlantic Canada and demonstrates that even a “drive-through province” deserves sustained historical examination.
Mechanical performance of Laser Powder Bed Fused maraging steel microlattices: Experimental and numerical evaluations
(University of New Brunswick, 2024-12) Behboodi, Behrang; Mohammadi, Mohsen
This study examines the design, fabrication, and mechanical performance of maraging steel BCCZ microlattices produced using Laser Powder Bed Fusion (LPBF) for energy absorption applications. Four lattice structures—rigid plate (RP), full strut plate (FSP), half strut plate (HSP), and parallel strut plate (PSP)—were analyzed for their compressive properties through uniaxial testing and finite element simulations using ABAQUS. The impact of plate configurations on mechanical behavior was evaluated, with simulation results calibrated and validated against experimental data, showing a deviation of only 1.1% in energy absorption. Among the designs, the rigid plate structure exhibited superior energy absorption capabilities in simulations, warranting further investigation of this design with one and three plates. These findings provide valuable insights into optimizing microlattice structures for improved mechanical performance, highlighting their potential in advanced energy absorption applications in additive manufacturing.
Pressure-based gait recognition: Feature extraction techniques for footwear-agnostic identity recognition
(University of New Brunswick, 2024-12) Salehi, Ala; Scheme, Erik
This research explores the development of a robust pressure-based gait recognition system, with a focus on reducing the impact of changes in footwear. Using two datasets; CASIA-D and a newly collected UNB dataset, we compare traditional and deep learning methods, including two novel architectures: UMAPNet for spatial feature learning and FootPart, a comprehensive spatiotemporal model. FootPart integrates local spatial partitioning with dynamic temporal modelling, achieving significant improvements in both closed-set and open-set verification tasks. Results show that FootPart maintains high accuracy under variable conditions, outperforming baseline models in identification tasks and demonstrating resilience to unseen footwear. This work underscores the importance of detailed spatial and temporal features in robust gait recognition, with implications for security, healthcare, and smart environments.
Floral trait evolution: Insights from bee-pollinated Penstemon to maternal effects in Brassica rapa
(University of New Brunswick, 2024-12) Rathnayake, Manoj Kaushalya; Parachnowitsch, Amy L.
My thesis explores the evolution of floral traits in angiosperms, focusing on phenotypic selection and maternal effects. Floral traits are influenced by both pollinators and abiotic factors, making it essential to study how these multiple selection agents shape various traits related to attraction, efficiency, and less-explored reward traits like nectar and pollen. Chapter 1 examines phenotypic selection in two bee-pollinated Penstemon species, analyzing 15 traits related to size, visual signals, pollinator fit, and rewards. Despite floral similarities, each species experienced different selection pressures, underlining the need to measure multiple functional traits to fully understand evolutionary dynamics. Chapter 2 explores how climate change-induced drought affects floral traits and pollinator interactions in Brassica rapa. A common garden experiment showed that drought reduced most floral traits except nectar concentration, which increased. Larger flowers were favored in drought conditions highlighting the context-dependent nature of maternal effects. While pollen limitation wasn't observed, water availability altered selection on plant height. Chapter 3 investigates how maternal effects and plasticity influence floral traits in Brassica rapa under different water conditions. Maternal drought stress significantly impacted offspring traits related to pollinator attraction and efficiency, particularly under continued drought. This highlights the importance of considering both maternal effects and environmental context in predicting plant responses to climate change. Overall, my work emphasizes the need for integrating studies on maternal effects and phenotypic selection to better understand how plants adapt to environmental stressors, enhancing knowledge of the evolutionary processes driving floral diversity and plant fitness.
Regional assessment of Atlantic salmon (Salmo salar) smolt resource use and body size in Eastern Canada
(University of New Brunswick, 2024-12) McCavour, Erin; Sacobie, Charles; Gillis, Carole-Anne
Atlantic salmon (Salmo salar) are ecologically, economically, and culturally significant, particularly for many Indigenous Peoples, providing sustenance and holding spiritual, ceremonial, and relational importance. They play a vital role in linking freshwater and marine ecosystems through nutrient transport and trophic interactions. Populations across Eastern Canada are at risk, with many designated as endangered, threatened, or of special concern. This thesis examines resource use and body size relationships of smolts from multiple Eastern Canadian rivers, using archival samples (2000-2016) and new accidental mortalities (2022-2023) collected collaboratively. Carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotopes were analyzed to assess resource use prior to migration, across sites, and as a predictor of smolt body size. Tissue analyses revealed individual dietary specialization, with a decrease in δ¹⁵N from long to short-term diets. Resource use was generally consistent across rivers within the same assigned population and was found to have a weak influence on body size.
Remote sensing to measure the physiology and foraging ecology of North Atlantic right whales in the Gulf of St. Lawrence, Canada
(University of New Brunswick, 2024-12) Lonati, Gina Lynn; Davies, Kimberley
Despite modern-day conservation efforts, many populations of baleen whales have not fully recovered since exploitation by commercial whaling. A better understanding of the physiology and foraging ecology of baleen whales would improve population monitoring, and the development of remote sensing technology offers non-invasive tools for collecting pertinent datasets on wide-ranging whales and their prey. My thesis used remote sensing to measure the physiology and foraging ecology of critically endangered North Atlantic right whales (Eubalaena glacialis, NARWs) in the southwestern Gulf of St. Lawrence (swGSL), Canada, where occupancy by NARWs increased around 2011 following an ocean regime shift. First, I developed, calibrated, and applied a method using drone-based infrared thermography to assess the internal body temperatures of NARWs. With this method, I established the first baselines of intranasal temperature for free-swimming baleen whales: 26.9 ± 1.7ºC in NARWs (n = 21). Second, I evaluated several methods for conducting drone-based photogrammetry with suboptimal photographs of NARWs. This helped me produce the first analysis of NARW body condition in the swGSL (summertime), which was significantly greater than in Cape Cod Bay (springtime) (p < 0.001). Across habitats, standardized widths of adult males (0.166 ± 0.012) and calves (0.170 ± 0.010) were significantly greater than those of lactating females (0.139 ± 0.001) (p < 0.024). Meanwhile, adult females in the Bay of Fundy two decades ago had considerably higher standardized widths (0.18 ± 0.02). Third, I provided context for this variation in body condition by describing prey field conditions associated with groups of foraging NARWs in the swGSL. Conditions were diverse, explained by the diel behaviors, life histories, and relative concentrations of three copepod prey species, including Calanus hyperboreus, which is less abundant in more southerly foraging habitats. Maximum prey concentrations occurred anywhere from 18 m deep to just above the seafloor, implying that NARWs likely alter their dive behavior to target different prey layers in the swGSL depending on the time of day and year. Overall, my thesis provides information for assessing change to the NARW population over time, which is essential for forecast modelling and effective management of this critically endangered species.
Dynamic volt-watt control strategy to improve fairness while mitigating overvoltage in distribution system due to high penetration of PV
(University of New Brunswick, 2024-12) Ahmed, Shafait; Diduch, Chris; Cardenas Barrera, Julian
The risk of overvoltage problems due to high penetration of distributed generation is a growing issue in low-voltage distribution networks. The use of Smart Inverters (SI) in the distribution system can help regulate voltage by controlling active and reactive power generation through volt-watt and volt-var droop control strategies. Conventional volt-watt and volt-var control methods use static parameters, which can lead to unnecessary curtailment of photovoltaics (PV) power, lower power factor, and/or reduction in PV hosting capacity. We propose two different algorithms that dynamically shape the volt-watt curve based on the voltage sensitivity of the PV nodes. Unlike centralized approaches, we adopt a distributed control strategy that minimizes reliance on extensive communication infrastructure, thereby improving system resilience. The proposed methods are simple to implement and require minimal communication among system components, enabling effective local control without the complexity of centralized coordination. To assess the performance of the proposed algorithms, we used the IEEE 37-bus system as a test network. Simulation results confirm the effectiveness of these strategies in enhancing fairness in PV curtailment and reducing overall curtailment levels. The proposed methods were implemented and evaluated through a co-simulation platform integrating the OpenDSS power simulator and Python, demonstrating their practical applicability and robustness in a simulated distribution system environment.
Modeling and aggregated control of residential electric thermal storage units
(University of New Brunswick, 2024-12) Yan, Hao; Diduch, Chris; Kaye, Mary Elizabeth
Electric thermal storage (ETS) plays an important role in the growth of thermal energy storage market. A large number of ETS devices can accomplish tasks of demand-side management (DSM) such as peak shaving to decrease the demand of electricity during peak hours. This thesis proposes four contributions to enable power system operators to issue an appropriate dispatch instruction to an ETS aggregator to accomplish DSM tasks over the control time horizon in the future. Firstly, a method to determine the forecasted lower bound of brick temperature of an ETS physical system (ETSPS) is derived when the zone temperature is regulated over a control time horizon. Secondly, a slope-based simplified model is derived to determine the forecasted brick temperature and help determine the forecasted reserve capacity of an ETSPS during the aggregated control over a control time horizon in the future. Thirdly, forecasted bounds of aggregated power shifted upward and downward from a forecasted baseline are formulated to allow system operators to select achievable dispatch instructions for tracking over a control time horizon in the future. Fourthly, the maximum time duration of tracking any achievable dispatch instruction in the future is forecasted with the application of the sloped-based simplified model. The system operators can issue an appropriate dispatch instruction at the current time for execution over a future control time horizon.
Assessing Atlantic salmon (Salmo salar) recovery across five Atlantic Canadian National Parks through juvenile abundance modelling
(University of New Brunswick, 2024-12) Robinson, John; Samways, Kurt
For decades, Atlantic salmon in Eastern North America have precipitously declined. In response, Fundy National Park (FNP) and Cape Breton Highlands National Park (CBHNP) implemented smolt-to-adult supplementation strategies within marine and freshwater rearing environments, respectively, Kouchibouguac National Park (KNP) planted fertilized eggs, and Gros Morne (GMNP) and Terra Nova National Park (TNNP) used community-based restoration approaches. To assess juvenile salmon population abundance through decline and restoration implementation of these parks, a Bayesian hierarchical model was developed to standardize single-pass and multi-pass electrofishing methodology, and estimate an index of juvenile density, at site and annual scale, using an electrofishing dataset covering 536 sites, over 49 years, across 24 rivers. Single-pass sites lack the accuracy of multi-pass methods but are an efficient sampling approach from a full catchment perspective. Increasing population trends were shown in some rivers (FNP, KNP), while others exhibited continued declines (CBHNP, KNP, GMNP) or modelling challenges (CBHNP, TNNP).
Investigation of a tri-articular mechanism in reducing energy expenditure in passive transfemoral prostheses
(University of New Brunswick, 2024-12) Kwok, Michelle Victoria; Biden, Edmund; Sensinger, Jon
Efficiency in human gait is dependent on coordination of muscle movements to provide a transfer of energy. Individuals with transfemoral amputations using a passive prosthesis lose efficiency in gait due to disruption of the flow of energy through the leg. By exploring joint coupling between the hip, knee, and ankle, transfemoral prostheses could be designed that improve user energy expenditure. This work investigated the hypothesis that by coupling joint motion through the leg, a passive transfemoral prosthesis can be designed that uses prosthetic joint motion to provide improved energy transfer; thus reducing user hip energy during gait. The hypothesis was explored through three specific aims of design, optimization, and testing. A transfemoral prosthesis was designed that implemented a tri-articular mechanism linking the motion of the hip and ankle. A simple five link walking model was adapted to implement prosthesis parameters, based on the developed prototype and used for co-optimization of the tri-articular spring stiffness and intact joint torques. The function of the developed tri-articular mechanism was explored in a pilot study, where increasing spring stiffness provided increasing prosthetic assistive torque. The results of each phase contributed to knowledge in the field surrounding the passive implementation of tri-articular joint coupling and co-optimization of a tri-articular spring and user joint torque. The findings of the three aims supported the hypothesis that joint coupling can be used as a means of energy transfer in a transfemoral prosthesis while demonstrating the need for future research. Optimization of the walking model showed the tri-articular spring parameter was weakly convex and could not be optimized in tandem with all four intact joints but could be optimized with one intact joint. In testing the developed tri-articular mechanism, the prosthesis motion allowed energy to be stored in the tri-articular spring, but the energy was not successfully transferred to the user. Results suggested that energy transfer to the user from work done by the assistive torque is dependent on the timing of energy release from the prosthesis spring. Future study is needed to evaluate the hypothesis and determine how to optimize a tri-articular mechanism to reduce user energy expenditure.
Evaluating factors that help an individual with ASD in maintaining employment, and the barriers that hinder them from maintaining employment from the employer's perspective
(University of New Brunswick, 2024-12) Dobson, Gillian; Landine, Jeff
The current qualitative study explored experiences from employers who have knowingly hired an individual on the autism spectrum who maintained employment. This study used the enhanced critical incident technique (ECIT) to understand factors that helped individuals with ASD in maintaining employment, and factors that hindered them from maintaining employment, from the employer’s perspective. Findings indicated that factors in the areas of managerial support and understanding, workplace environment and education, individualized approaches, additional support and integration, and job fit were helpful with the individual’s success in maintaining employment for at least one year. Factors in the areas of lack of understanding and support, individual challenges and anxiety, support and resources, personal factors, and skills and adaptability were hindering factors in the individual’s success with their employment.
Latin American women’s intentions and decision-making processes about cervical cancer screening: A grounded theory research
(University of New Brunswick, 2024-12) Moreira, Cecilia Assuncao; Busolo, David
Cervical cancer screening rates are low among Latin American immigrants due to various barriers. However, little is known about what motivates these women to attend screenings. Understanding their decision-making processes is essential for increasing screening uptake. Therefore, the purpose of this grounded theory study was to examine the decision-making processes that Latin American women use about cervical cancer screening. Fifteen women were interviewed individually, with data collection and analysis occurring concurrently. Interview transcripts were analyzed using a comparative approach. The final product of this research was the theory of Latin American women’s search for health services: A model of distancing from cervical cancer screening. The findings highlight the decision-making processes that influence screening participation and provide valuable insights into engaging these women. These results can help health professionals improve screening uptake and offer more equitable services to Latin American immigrants in New Brunswick and other regions.
Development, testing, and ocean mapping application of three-dimensional baroclinic hydrodynamic ocean modeling at a variety of scales
(University of New Brunswick, 2024-12) Alleosfour, Ahmadreza; Church, Ian
To investigate the improvement in representing the general circulation and baroclinic condition of the Bay of Fundy and Minas Basin, two high-resolution 3D baroclinic hydrodynamic models have been developed using Finite-Volume Community Ocean Model (FVCOM). The effect of surface forcing resolution is assessed by prescribing two commonly used atmospheric forcing models in the region. The model simulations are validated against the available observations and collected Conductivity, Temperature, and Depth (CTD) data during a benthic habitat campaign in July 2018, the tidal constituents, Sea Surface Temperature (SST) data from satellite, and historical published current meter data. The models show a good agreement in capturing the tide both in the Bay of Fundy and Minas Basin and represented some improvement against the operational models in the region. In addition, the improvement in representing the baroclinic condition of the Bay both at the surface and water column is reported. The coarse prescribed surface forcing resulted in a warmer surface temperature in the Bay, while the higher resolution one generated a better agreement with the observations. Also, the model simulations have been implemented in an innovative approach to evaluate the partitioning of the hydrographic survey domain and provide insight into the multibeam echosounder depth uncertainty due to using a synthetized CTD profile, based on different criteria and limitations of hydrographic survey vessels for both Minas Basin and Saint John Harbor.
The secret world of ditches: An ecosystem service approach to linking aquatic and terrestrial ecosystems in agro-landscapes
(University of New Brunswick, 2024-12) Rideout, Natalie K; Baird, Donald J
Agriculture is intensifying and extensifying, both across Canada and globally, resulting in increasing homogenisation of agro-landscapes. In non-arid zones, this land use change has resulted in the loss of wetland habitat and subsequent replacement with drainage ditches, i.e., linear features designed to control field water levels. These artificial watercourses are designed for utility and are thus managed to enhance crop production. To maximise utility, drains are frequently dredged and riparian vegetation removed. Despite this, in otherwise homogeneous and depauperate landscapes, drainage ditches and agricultural streams can serve as havens for biodiversity, including riparian bird populations. I examined how land use practices within agricultural landscapes influence ecosystem functioning/ services of remnant aquatic and riparian habitats, including drainage ditches and riparian hedgerows. This thesis comprises three data chapters. The first describes how agricultural management affects ecosystem functioning in drainage ditches through alteration of flows. The second examines the role of aquatic insect secondary production as an ecosystem service for riparian bird communities in an agriculturally-dominated watershed of eastern Ontario. The third data chapter examines how agriculture influences dietary and nutritional linkages between tree swallows (Tachycineta bicolor), riparian insects and emerging aquatic insects. Overall, the research described in this thesis lends support to three key management and policy recommendations. 1) Promoting mosaicked agricultural landscapes as an alternative to intensive agriculture can have wide-ranging benefits to riparian and aquatic ecosystem functions and services. 2) One Health principles—which balance human, animal and environmental health—are critical to better balance biodiversity protection with food production in working landscapes, and agricultural producers should be educated on how to increase their application. 3) Drainage ditches represent important habitat on agro-landscapes; thus, their management and its timing should be undertaken in mind with nature, and continued provisioning of ecosystem functions and associated services. Moreover, it is important to recognise the ecological potential of these remnant habitats so that working landscapes can operate while supporting biodiversity and ecosystem health, finding a balance between food production and environmental stewardship.
Surveilling Sex: Prostitution and the East German Stasi, 1950-1989
(University of New Brunswick, 2024-12) Bailey, Jordyn; Todd, Lisa
This dissertation offers a new approach to the history of the East German Ministry for State Security (Ministerium für Staatssicherheit, MfS, Stasi). It uses feminist methodologies of care to embed the experiences of female informers classified by the Stasi as ‘sexually promiscuous’ in broader frameworks of gender and sexuality research and explores the convergence of Stasi surveillance and prostitution control in the German Democratic Republic. The MfS and its extended arm, ‘Working Area 1’ of the Criminal Police (K1), considered ‘promiscuous’ women to be social pariahs, sources of venereal diseases, and threats to the Socialist state, but they also acknowledged that their connections to ‘class enemies’ made them valuable informants. To identify and exert control over women, the Stasi used the state’s existing carceral framework to take advantage of larger state efforts to regulate prostitution, a phenomenon that was expected to disappear under socialism, in East Germany. Therefore, the dissertation argues that only by examining prostitution, venereal disease, and the Stasi surveillance network in tandem, can we fully understand the gendered exploitation of lives in the GDR. This study uses previously unexamined Stasi files to explore state intervention into sexual lives that state socialism considered morally and medically dangerous. It begins by documenting female Stasi informers’ encounters with the police, and their frequent stays in social homes, workhouses, prisons and venereological wards prior to their recruitment. It then explores women’s recruitment experiences, which often involved threats of legal action if they did not agree to collaborate. Next, the study examines how female informers used their past experiences navigating the carceral and healthcare systems to ‘exit’ the Stasi surveillance system. The study is the first to detail the sexual abuse perpetrated by male officers on the female informants they considered ‘available.’ Finally, it analyzes constructions of Stasi informers in contemporary popular culture. By foregrounding the experiences of vulnerable women and making their roles as social and political actors visible, this dissertation offers a necessary new analysis of Stasi practices. It also highlights the broader historiographical need for greater focus on gender and sexuality within the Stasi.
Estimating fish mortality in a hydroelectric turbine using computational fluid dynamics and autonomous device methods
(University of New Brunswick, 2024-12) Hamel, Philippe Remi; Haralampides, Katy; Jeans, Tiger
The goal of this study was to use computational methods to estimate risk to fish as they pass through a large hydroelectric turbine, where some fish can be injured or killed. A large Kaplan-type hydroelectric turbine was modelled with computational fluid dynamics at two different flowrates, and simulation results were validated with field measurements obtained using autonomous sensors that were deployed through the same turbine while it operated at the simulated flowrates. Simulation results and the Biological Performance Assessment method were then used to evaluate mortality risk to three fish species during turbine passage at each simulated flowrate. Results indicated that fish mortality consistently occurs in the investigated turbine, and that mortality risk for the examined species is higher at the largest simulated flowrate. Mitigation measures such as operational changes or turbine upgrades are recommended to lower risk of mortality to fish that pass through the turbine.
Concentric and eccentric compressive material characterization of polyurethane disc bridge bearings
(University of New Brunswick, 2024-12) Thibodeau, Nicholas William; Lloyd, Alan
Disc bridge bearings are immerging as a popular choice for modern bridge designers. The key constituent of the bearings is their polyurethane disc as it can withstand high vertical loads without excessive deflection yet may deform to permit superstructure rotations. This thesis presents an experimental and numerical investigation of polyurethane used in disc bridge bearings under compressive and rotational loads. The primary objectives of the research were to characterize the experimental and numerical results to aid in the design and behavioural understanding of disc bridge bearings. Small-scale polyurethane specimens were tested under cyclic uniaxial compression with concentric and eccentric loading to develop stress-strain and moment-rotation relationships. Concentric testing was also repeated with specimens conditioned to 0°C to provide preliminary investigations into the low-temperature behaviour of the polyurethane. Characteristics of the material such as the influence shape factor, stiffness behaviour, residual strain, loading history, and rotational predictability were discussed.

Browse

Recent Submissions