Theses, Dissertations, and other Required Graduate Degree Essays

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This collection contains digitized SFU theses except for those theses submitted within the last 12 months. If you cannot find the thesis you are looking for please search Recently Submitted Theses as it may be a recently submitted thesis and thus not yet available in Summit.

Variation in indices of tag reporting rate in the British Columbia Sablefish (Anoplopoma fimbria) fishery

Author: 
Date created: 
2020-12-14
Abstract: 

Mathematical models in fisheries research that utilize tag return data require an estimate of the proportion of commercially caught tags that are returned (i.e., the tag reporting rate). In this study, I estimated an index of tag reporting rate in the British Columbia Sablefish fishery by comparing the prevalence of tags in the commercial fishery catch to the tag prevalence of a fishery-independent survey. I determined the effect of region, year, gear type, and size by fitting generalized linear models to the estimates of this index. The tag reporting rate index varied across size classes and gear types, with high indices of tag reporting rate for fish larger than the commercial size limit, and in the trap fishery. I concluded that factors such as gear selectivity and handling of catch are likely impacting the indices of tag reporting rate. Future studies could investigate the drivers of variation in the index of tag reporting rate and seek to identify sources of bias. Potential clustering of tagged fish should also be investigated.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Sean Cox
Luke Rogers
Department: 
Environment: School of Resource and Environmental Management
Thesis type: 
(Project) M.R.M.

Sports match outcome prediction with graph representation learning

Author: 
Date created: 
2022-04-27
Abstract: 

Predicting the winner of a sports match is a widely studied challenging problem of interest to many stakeholders (media, teams, fans, bookmakers). Various machine learning methods have been used in this field. However, the majority of past research has focused on learning about teams, not players. In other words, players’ strength and lineup information, has not been considered in most previous works, despite its significant impact on match outcome prediction. In competitive team sports, the outcome can depend on complex interactions between opposing teams and interactions among players and teams. This thesis develops a novel approach to match outcome prediction that leverages graph representation learning to model team-team and team-player interactions. Both teams and players correspond to nodes in a Spatio-Temporal graph. Node embeddings capture how team/player characteristics jointly influence match outcomes. Empirical results on a dataset of nine different football leagues demonstrate the superior performance of our graph representation approach.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Oliver Schulte
Department: 
Applied Sciences: School of Computing Science
Thesis type: 
(Thesis) M.Sc.

Fast deep gaussian process modeling and design for large complex computer experiments

Author: 
Date created: 
2022-04-29
Abstract: 

Computer models, or simulators, are widely used as a way to explore complex physical systems, but can be computationally expensive to evaluate or are not readily available to the broad scientific community. In either case, an emulator is used as a surrogate. Stationary Gaussian process emulators are often used to stand in for the computer models. In many cases, the computer model response surface does not resemble a realization of a stationary Gaussian process. Deep Gaussian processes have been shown to be capable of capturing non-stationary behaviors and abrupt regime changes in the response surface. In this thesis, we explore some of the properties of two common deep Gaussian process models for computer model emulation. We propose new methodology for one of the models so that it can serve as a computer model emulator. We introduce a new parameter that controls the amount of smoothness in the deep Gaussian process layers. We also adapt a stochastic variational approach to our deep Gaussian process model which allows for prior specification and posterior exploration of the smoothness of the response surface, thereby giving good predictive performance. Our approach can be applied to a large class of complex computer models, and scales to arbitrarily large simulation designs. The proposed methodology was motivated by the need to emulate an astrophysical model of the formation of binary black holes. Lastly, we propose a sequential design approach by combining the non-stationary deep Gaussian process model with an expected improvement based criterion. An adaptation in the deep Gaussian process prediction method facilitates the proposed sequential design approach. Our methods are illustrated in a series of synthetic examples and the real-world application.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Derek Bingham
Department: 
Science: Department of Statistics and Actuarial Science
Thesis type: 
(Thesis) Ph.D.

Impacts of roads and cranberry agriculture on bog wetland hydrology with restoration recommendations for Langley Bog

Author: 
Date created: 
2022-04-19
Abstract: 

Bog wetlands store a disproportionate amount of carbon for their size, making their conservation an important part of climate change mitigation. The goal of this project is to investigate how roads and agriculture impact the hydrology and vegetation composition of Langley Bog and to provide restoration recommendations. Langley Bog, in Langley Township, BC, is a formerly mined peatland with a fill road running through the center and surrounded to the north and west by cranberry farms. From November 2020 to November 2021, depth to water table and pH were measured monthly at nine wells. Twelve vegetation transects were completed in July 2021. Sites adjacent to the road were correlated with a decrease in summer water level, while sites adjacent to the cranberry farms were correlated with an increase in spring pH levels. A positive relationship was found between an increase in water-table level and percent cover of wetland obligate species. Roads may be lowering the water table through subsidence and drainage. The cranberry farms may be increasing the pH through the deposition of fertilizer. These impacts may have been exacerbated by the unusually dry 2021 summer season. To raise the water table, tree and road removal is recommended to restore lateral flow and decrease evapotranspiration. Culverts installed under the primary fill road will provide additional hydrologic connectivity. Building a berm at outlet points will also help prevent water loss, keeping a higher water table. To increase carbon sequestration, Sphagnum mosses are to be reintroduced to denuded areas in Langley Bog. Tree removal will help in moss establishment by maintaining open bog conditions free from shading. Existing rare ecosystems present in Langley Bog would benefit from the removal of point source pollutants and invasive species on the site. Given the urgency of climate change, restoring the functionality of Langley Bog and protecting the existing stored carbon is a practical and achievable way to move Metro Vancouver a step closer to carbon neutrality.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Douglas Ransome
Department: 
Environment: Ecological Restoration
Thesis type: 
(Project) M.Sc.

Team-based Staffing Optimization for an Urgent and Primary Care Centre

Date created: 
2022-04-08
Abstract: 

Urgent and primary care centres (UPCCs) provide both walk-in services for urgent healthcare needs and booked appointments for longitudinal care. UPCCs utilize multi-disciplinary teams of healthcare professionals who collaborate to provide client care. This thesis develops a new approach to optimize team-based staffing at a UPCC in Vancouver, British Columbia. The core of the approach is a discrete event simulation that estimates client access indicators based on the UPCC operational profile and client visit data. The analysis compares two algorithms that minimize staffing levels subject to access targets given by the time-dependent expected proportion of simulated clients who leave due to a prolonged wait. One approach combines an extension of an iterative, simulation-based algorithm for small-interval staffing with an integer programming formulation for shift-based staffing. Another approach optimizes shift-based staffing through simulation optimization. Both approaches make staffing recommendations to improve care access.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Tamon Stephen
Alexander Rutherford
Department: 
Science: Department of Mathematics
Thesis type: 
(Thesis) M.Sc.

Husserlian phenomenology and its methodological significance

Author: 
Date created: 
2022-04-06
Abstract: 

This thesis covers three major aspects of Husserl’s phenomenology that may be particularly of interest to psychologists. I discuss Husserl’s critique of naturalism and specifically his critique of naturalistic psychology. In so doing, I consider Husserl’s historical investigation that focuses on the development of naturalism since early modernity. I also introduce Husserl’s construction of transcendental philosophy that aims to overcome the problem imposed by naturalism. Then, I explore Husserl’s analysis of intentionality viewed as the essential character of consciousness. Both the pretranscendental and the transcendental conceptions of intentionality are discussed in order to demonstrate the methodological status of phenomenological reduction. Finally, I explicate and examine Husserl’s different approaches of reduction, the process of eidetic analysis, and the relationship between psychology and phenomenology. I argue that phenomenology can not only contribute to empirical psychological investigations but also help form a critical attitude about psychology in general and its underlying philosophical presuppositions.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Tim Racine
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Thesis) M.A.

Investigations towards non-invasive blood analysis using resonance Raman at the bulbar conjunctiva

Author: 
Date created: 
2022-01-25
Abstract: 

Dependency upon infrastructure and skilled workers spurs the need for innovation in blood analysis devices to improve accessibility and efficiency. A proposed method of non-invasively determining biomarkers in blood is to measure the resonance Raman response at the bulbar conjunctiva allowing for selectivity, sensitivity, and access to blood vessels exposed to ambient air. In order to do so, several key questions are required to establish this method, one being whether or not biomarkers can be detected, identified, and quantified at biological concentrations in whole blood. The following thesis measures a single biomarker (all-E beta carotene) in an organic solvent (ethanol) at biological concentrations and preliminary results detecting carotenoids in diluted bovine calf serum. Experimental results are provided to demonstrate peak locations at 1008, 1158 and 1525 cm-1 and a linear response (R2 > 0.99) between resonance Raman peak intensity and concentration of beta carotene in ethanol at biological concentrations (SNRB = 2.9 at ~1 μM).

Document type: 
Thesis
File(s): 
Supervisor(s): 
Andrew Rawicz
Bruno Jaggi
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) M.A.Sc.

Spatial linkages and stability of Pacific salmon

Author: 
Date created: 
2022-04-28
Abstract: 

Migratory animals cross the spatial boundaries of ecosystems and subsidize food web productivity through the input of externally derived resources. However, human activities have altered such spatial linkages through the spread of non-native species. Moreover, the conservation and management of migratory animals is complicated by the broad spatial scales over which they occur. In this thesis, I use field-based studies to examine the spatial linkages created by the Chinook salmon invasion of Patagonia, southern Chile, and apply a metacommunity framework to understand the spatial stability of Pacific salmon. First, I investigate whether Chinook salmon in Patagonia subsidize stream algae through the delivery of marine-derived nutrients. I show that marine-derived nutrients increase algal biomass, indicating that salmon have established a novel linkage between freshwater and marine ecosystems in Patagonia. Next, I use field-based observations and a literature review to examine the trophic interactions that have emerged following this invasion. I describe novel trophic interactions and present evidence that the pathways of salmon nutrient incorporation in North American food webs have functionally re-emerged in South America. Lastly, I use spatio-temporal reconstructions of annual Pacific salmon abundance across the North Pacific Ocean and within northern British Columbia (BC) to test the hypothesis that ecological properties temporally stabilize across larger areas. Across six decades of abundance estimates, I find that the temporal stability of annual salmon abundance is significantly greater in the North Pacific than in northern BC due to the stabilizing effect of spatial asynchrony. I also show that hatchery production of salmon has only a marginal effect on local stability in regions with viable salmon stocks, calling into question the efficacy of hatcheries in stabilizing salmon populations. Overall, this thesis enhances our understanding of the ecological impacts of Patagonian salmon and the effect of salmon management practices on stability while also addressing broader patterns in the trophic interactions that emerge following biological invasions and the emergent properties of ecological systems across spatial scales.

Document type: 
Thesis
File(s): 
Supervisor(s): 
John Reynolds
Department: 
Science: Biological Sciences Department
Thesis type: 
(Thesis) Ph.D.

An investigation of early forms of index finger extension and joint engagement in the development of pointing

Author: 
Date created: 
2021-12-17
Abstract: 

Human infants begin to point to objects around their first birthday, typically before they learn their first words. Pointing in infancy is associated with later social and communicative development and involves a level of complexity not found in other gestures, which is evident in the many functions it serves. Despite extensive research on pointing, there is a lack of consensus regarding the ontogenetic origins of this gesture. I argue that one reason for this is that the currently dominant cognitivist theoretical approach is grounded in problematic metatheoretical assumptions that constrain research in this area. For example, this approach has resulted in a focus on what communicative intentions infants are trying to express when they point, which I argue overlooks the process through which these intentions develop. An alternative is an activity-based approach, grounded in the process-relational worldview, which avoids pre-supposing communicative intentions in infants’ emerging gestures and instead aims to investigate how this form of understanding develops within shared activities. Accordingly, the present dissertation is based on the activity-based theory that pointing emerges through infants learning to anticipate others’ responses to their initially non-communicative index finger use, within joint engagement with others. Through analyses of 33 caregiver-infant dyads’ interactions within three routine activities at two time points, I found that index finger extensions not yet coordinated with the infant’s gaze, and tactile exploration with the index finger at 9 months were significantly positively correlated with pointing at 12 months. Infants engaged in tactile exploration with all fingers before using the index finger to do this, which emerged and became more established through transitional phases. This was associated with time spent in infant-led joint engagement with caregivers, which was also significantly positively correlated with pointing three months later, whereas time spent in parent-led joint engagement was not. Finally, longitudinal qualitative observations of three dyads’ joint engagement episodes suggest that alternating between responding to and re-directing the infant’s attention might be more strongly associated with the emergence of pointing when compared to frequency of parental responses. The relevance of these findings for theories of communicative development and associated metatheoretical assumptions is discussed.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Jeremy Carpendale
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Thesis) Ph.D.

Reality television in the Chinese mediascape: A case study of the reality-variety program who’s the murderer

Author: 
Date created: 
2021-08-26
Abstract: 

Reality television is playing an increasingly important role in our daily lives; however, there have been insufficient research on the topic, especially in the reality-variety format. In Western public opinion, it is believed that the Chinese media system is dictated by the CCP, that it is more valuable to study informational content, and that Chinese audiences are passive consumers. However, an analysis of the reality program Who’s the Murderer will suggest otherwise. The analysis for the project was three-fold: (1) an analysis the production and political economy of culture; (2) textual analysis of the program contents; and (3) audience reception of the show based on the analysis of Weibo posts. This study demonstrates that the market forces are playing an increasing role in media production, there exists a blending of informational content and entertainment content within reality television, that the content may lead to social activism, and that Chinese audiences are active participants in the online environment.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Siyuan Yin
Department: 
Communication, Art & Technology: School of Communication
Thesis type: 
(Extended Essay) M.A.