Theses, Dissertations, and other Required Graduate Degree Essays

Receive updates for this collection

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.

Structure-property relationships in sterically-congested proton-conducting poly(phenylene)s: The impact of backbone linearity

Author: 
Date created: 
2020-04-09
Abstract: 

Decarbonatization of the World’s primary energy supply is becoming increasingly more important due to a rapidly changing climate. A hydrogen-based economy offers a potential means of zero-carbon energy production through the use of fuel cells and water electrolyzers. The development of robust, thermochemically-stable hydrocarbon-based proton exchange membrane materials that resist swelling for use in these devices represent a significant hurdle in their commercial adoption. In this thesis, the structure-property relationship of hydrocarbon-based sulfonated phenylated poly(phenylene) proton exchange membranes possessing either angled or linear backbone moieties is discussed. Polymers were synthesized using either bent (ortho or meta), or linear (para) biphenyl linkages and evaluated for differences in physical and electrochemical properties. Model compounds, structurally-analogous to the polymers, were prepared and characterized using spectroscopic and computational methods to elucidate structural differences and potential impacts on the properties of the respective polymers. A highly angled ortho biphenyl linkage resulted in a sterically hindered, rotationally-restricted molecule. When incorporated into a homo-polymer, the angled ortho biphenyl moiety was found to prevent membrane formation. The angled meta biphenyl-containing homo-polymer, while forming a membrane, exhibited a 74% increase in volumetric expansion, 31% reduction in tensile strength, and 72% reduction in the elongation at break when compared to the linear para biphenyl-containing analogue. The differences observed are attributed to a rotationally-restricted backbone in the angled biphenyl systems. Co-polymers containing a small fraction (≤5%) of the ortho or meta biphenyl linkage in an otherwise para biphenyl containing system were found to have a significantly lower degree of swelling than those containing solely para biphenyl linkages. Collectively, the work presented in this thesis suggests that incorporating angled biphenyl linkages into sulfonated phenylated poly(phenylene)s leads to highly rigid, inflexible backbones that prevents chain entanglement and the formation of free-standing membranes.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Steven Holdcroft
Department: 
Science: Department of Chemistry
Thesis type: 
(Thesis) M.Sc.

Linguistic variation and ethnicity in a super-diverse community: The case of Vancouver English

Author: 
Date created: 
2020-12-11
Abstract: 

Today, people with British/European heritage comprise about half (49.3%) of the total population of Metro Vancouver, while the other half is represented by visual minorities, with Chinese (20.6%) and South Asians (11.9%) being the largest ones (Statistics Canada 2017). However, non-White population are largely unrepresented in sociolinguistic research on the variety of English spoken locally. The objective of this study is to determine whether and to what extent young people with non-White ethnic backgrounds participate in some of the on-going sound changes in Vancouver English. Data from 45 participants with British/Mixed European, Chinese and South Asian heritage, native speakers of English, were analyzed instrumentally to get the formant measurements of the vowels of each speaker. Interview data were subjected to thematic analysis that aimed to describe to which extent each participant affiliated with their heritage. The results of the descriptive and inferential statistical analysis showed that, first, the vowel systems of these young people are similar and they all are undoubtedly speakers of modern Canadian English as described in previous research (Boberg 2010). Second, all three groups participate in the most important changes in Canadian English: the Canadian Shift, Canadian Raising, the fronting of back vowels, and allophonic variation of /æ/ in pre-nasal and pre-velar positions. Some differences along the ethnic lines that were discovered concern the degree of advancement of a given change, not its presence or absence. Socio-ethnic profiles of the participants created on the basis of the thematic analysis can be roughly put into two categories, mono- and bicultural identity orientation (Comănaru et al. 2018). Great variability is described both within and across groups, with language emerging as one of the most important factors in the participants’ identity construction. Exploratory analysis showed some tendencies in vowel production by speakers with mono- and bicultural orientations, with differences both among and within two non-White groups. The findings of the study call into question both our understanding of the mechanisms of language acquisition and our approach to delimiting and describing speech communities in super-diverse urban centers.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Panayiotis Pappas
Department: 
Arts & Social Sciences: Department of Linguistics
Thesis type: 
(Thesis) Ph.D.

Deep learning for optical coherence tomography angiography: Quantifying microvascular changes in diabetic retinopathy

Author: 
Date created: 
2020-12-18
Abstract: 

Optical Coherence Tomography Angiography (OCT-A) permits visualization of the changes to the retinal circulation due to diabetic retinopathy (DR), a microvascular complication of diabetes. Machine learning applications have directly benefited ophthalmology, leveraging large amounts of data to create frameworks to aid clinical decision-making. In this thesis, several techniques to quantify the retinal microvasculature are explored. First, high-quality, averaged, 6x6mm OCT-A enface images are used to produce manual segmentations for the corresponding lower-quality, single-frame images to produce more training data. Using transfer learning, the resulting convolutional neural network (CNN) segmented the superficial capillary plexus and deep vascular complex with performance exceeding inter-rater comparisons. Next, a federated learning framework was designed to allow for collaborative training by multiple participants on a de-centralized data corpus. When trained for microvasculature segmentation, the framework achieved comparable performance to a CNN trained on a fully-centralized dataset.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Marinko Sarunic
Department: 
Applied Sciences: School of Engineering Science
Thesis type: 
(Thesis) M.A.Sc.

An adaptive discretization method for the shortest path problem with time windows

Author: 
Date created: 
2020-12-18
Abstract: 

The Shortest Path Problem with Time Windows (SPPTW) is an important generalization of the classical shortest path problem. SPPTW has been extensively studied in practical problems, such as transportation optimization, scheduling, and routing problems. It also appears as a sub-problem in the column-generation process of the vehicle routing problem with time windows. In SPPTW, we consider a time-constrained graph, where each node is assigned with a time window, each edge is assigned with a cost and a travel time. The objective is to find the shortest path from a source node to a destination node while respecting the time window constraints. When the graph contains negative cycles, the problem becomes Elementary Shortest Path Problem with Time Windows (ESPPTW). In this thesis, we adopt the time-expanded network approach, extend it by incorporating the adaptive expansion idea and propose a new approach: Adaptive Time Window Discretization(ATWD) method. We demonstrate that the ATWD method can be easily combined with label setting algorithms and label correcting algorithms for solving SPPTW. We further extend the ATWD embedded label correcting algorithm by adding k-cycle elimination to solve ESPPTW on graphs with negative cycles. We also propose an ATWD based integer programming solution for solving ESPPTW. The objective of our study is to show that optimal solutions in a time-constrained network can be found without first constructing the entire time-expanded network.

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

Determining the jet energy scale for ATLAS in the Z+Jet channel

Author: 
Date created: 
2020-11-10
Abstract: 

This thesis presents a determination of the jet energy scale for the ATLAS detector using in-situ measurements. This calibration is critical, as jets are found in many analyses, and the energy measurement of jets contributes significantly to the uncertainty in numerous ATLAS results. The energy of the jet is initially taken to be the detector measurement, but this is lower than the true energy because the detector is calibrated for electromagnetic particles, not jets. One can find a correction to this energy by balancing the jet's transverse momentum against a well-measured reference object. Directly calibrating the calorimeter-level jet to the particle-level is called Direct Balance; here, a different method called the Missing ET Projection Fraction (MPF) method is used instead, which balances the pt of the recoiling system against the reference object. The MPF's pile-up resistant nature makes it more suitable to use in the ATLAS environment. Results for the MPF method in the Z+Jet channel are presented. A relative calibration of data to Monte Carlo simulation is provided, including a complete systematic uncertainty analysis. The uncertainty on the in-situ calibration is reduced to around 1% for most transverse momenta.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Michel Vetterli
Department: 
Science: Department of Physics
Thesis type: 
(Thesis) M.Sc.

From the field to headquarters: What is learned from nursing insight on quality of care in humanitarian settings?

Author: 
Date created: 
2020-12-04
Abstract: 

Quality of care in humanitarian healthcare is a challenge requiring a partnership between the project and the operational center, necessitating a way to bridge the divide between “on the ground” knowledge and the understandings in headquarters (HQ). Médecins Sans Frontières’ (MSF) data collection from internationally recruited nurses (IRN) leaving humanitarian healthcare projects is meant to addresses this challenge. The objectives of this study are to appraise if MSF’s “End of Mission” (EoM) survey is an effective means of harvesting knowledge about the quality of care in projects and analyze the disjuncture or congruence between MSF field and HQ perceptions. This study uses a mixed methods approach combining survey analysis and interviews with key informants, including nurses and MSF HQ coordinators. Findings indicate that the EoM survey data is effective at transferring some knowledge but lacks the breadth of nurses’ experience-based knowledge that can be found in stories which create context.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Elizabeth Cooper
Department: 
Arts and Social Sciences: School for International Studies
Thesis type: 
(Thesis) M.A.

Systematic comparison of designs and emulators for computer experiments using a library of test functions

Author: 
Date created: 
2020-12-16
Abstract: 

As computational resources have become faster and more economical, scientific research has transitioned from using only physical experiments to using simulationbased exploration. A body of literature has since grown aimed at the design and analysis of so-called computer experiments. While this literature is large and active, little work has been focused on comparing methods. This project presents ways of comparing and evaluating both design and emulation methods for computer experiments. Using a suite of test functions — in this work we introduce the Virtual Library of Computer Experiments a procedure is established which can provide guidance as to how to proceed in simulation problems. An illustrative comparison is performed for each context; putting three emulators, then four experimental designs up against each other; while also highlighting possible considerations for test function choice.

Document type: 
Graduating extended essay / Research project
File(s): 
Supervisor(s): 
Derek Bingham
Department: 
Science: Department of Statistics and Actuarial Science
Thesis type: 
(Project) M.Sc.

The valley of desire: A study of Kashmir as portrayed through popular Indian cinema

Author: 
Date created: 
2020-08-31
Abstract: 

Indian-occupied Kashmir has been a conflicted territory since 1947. This paper studies the representation of Kashmir and its civilian population in popular Hindi films. As Bollywood has an immensely dedicated audience, both in India as well as globally, the sensitive issues surrounding Kashmir make for extremely sought-after and therefore potentially influential content in films. I argue that these films reflect a sharp bias and a myopic approach towards showcasing the area and its civilian population. This paper employs the use of film analysis and critical discourse analysis to examine seven films — Mission Kashmir (2000), Yahaan (2005),Fanaa (2006), I am (2010), Lamhaa (2010), Haider (2014) and Hamid (2018) — to support the argument. The results show that all the films except Haider and Hamid misrepresent or underrepresent the realities of Kashmir. The content is highly Islamophobic and hyper-nationalistic, undermining the role of the local population in the whole conflict scenario.

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

Understanding women's autonomy: Wives of Punjabi truck drivers in Punjab and BC

Author: 
Date created: 
2021-01-18
Abstract: 

This study examines the widely held view that Punjabi women lack autonomy, having relatively little freedom to make their own choices. Through a survey questionnaire and in-depth interviews, the research explored understandings of their autonomy among 17 truck driver wives in Punjab and 14 in British Columbia, taking account of the implications of the lengthy absences of the women’s husbands. The study finds that the way women perceive and experience autonomy must be understood and measured with more nuance than is the case in much previous research. This has placed too much emphasis on attempts to compress perceptions and experiences of autonomy into discreet, quantitative measures. Research for this paper revealed many inconsistencies in commonly understood indicators of autonomy, highlighting the importance of examining the diverse circumstances of women and the unpredictability of human agency.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Irene Pang
Department: 
Arts and Social Sciences: School for International Studies
Thesis type: 
(Thesis) M.A.

English in the expanding circle of Morocco: Spread, uses, and functions

Author: 
Date created: 
2021-01-20
Abstract: 

Research using Kachru’s (1984) World Englishes theoretical framework and Three Circles model has produced a wealth of knowledge about the spread and functions of English to speech communities around the world. However, there is a recognition that disproportionate attention has been accorded across these spheres. The most compelling argument outlining this gap in the literature was offered by Berns (2005) over a decade ago and was reiterated by Elyas and Mahboob (2020) just recently. Berns (2005: 85) concluded that while the bulk of academic research has focused on the use of English in Inner and Outer Circle contexts, the Expanding Circle remains mostly overlooked. Elyas and Mahboob (2020: 1), who co-edited a special journal issue on the North African and Middle East contexts, underscored that the topic of English in these regions ‘is largely under-studied and undertheorized.’ Following Berns’ remarks, numerous studies have focused on this underrepresented context. Nevertheless, despite their solid contributions, these investigations remain insufficient for constructing a comprehensive understanding of the distinct dynamics of the Expanding Circle. To contribute to the Expanding Circle literature, this exploratory, qualitative, macrosociolinguistic study employs Kachru’s (1984) World Englishes theoretical framework to investigate in greater depth the spread, functional range, and domains of English use in the multilingual country of Morocco. Specifically, this study initially provides an overview of the various languages used in Morocco, then outlines the history of its contact with the English language. It next explores English use in Moroccan media, examining in detail the language’s wide-ranging uses in broadcast, digital, print, and film media. This is followed by an in-depth examination of the linguistic landscape of the metropolitan city of Casablanca, with a focus on shop signs and outdoor advertisements. Whilst the users and uses of the English language are the major focus of analysis, additional attention is given to what such a spread means for the other four historically well-established languages of use within this Expanding Circle context: Arabic, French, Spanish, and the indigenous language Tmazight. A further aim of this study is to contribute new perspectives to the existing literature on the distinct dynamics of the Expanding Circle in general.

Document type: 
Thesis
File(s): 
Supervisor(s): 
Suzanne K. Hilgendorf
Department: 
Arts & Social Sciences: Department of Linguistics
Thesis type: 
(Thesis) Ph.D.