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.

Optimization for mobile deep learning applications with edge computing

Author: 
Date created: 
2018-12-14
Abstract: 

The emergence of deep learning has attracted the attention from a wide range of fields and brought a large number of related applications. With the rapid growth of mobile computing techniques, numerous deep learning applications are designed for the mobile end. However, since deep learning tasks are computational-intensive, the limited computation resource on the mobile device cannot execute the application effectively. Traditional approach is to push the data and the workload to the remote cloud. Meanwhile, it introduces a high data transmission delay and possibly bottlenecks the overall performance. In this thesis, we apply a new rising concept, edge computing, for mobile deep learning applications. Comparing with cloud learning, the communication delay can be significantly reduced by pushing the workload to the near-end edge. Unlike the existing edge learning frameworks only concerning inference or training, this thesis will focus on both and put forward different optimization approaches towards them. Specifically, the thesis proposes a layer-level partitioning strategy for inference tasks and an edge compression approach with the autoencoder preprocessing for training tasks, to exploit all the available resources from the devices, the edge servers, and the cloud to collaboratively improve the performance for mobile deep learning applications. To further verify the optimization performance in practice, we formulate a scheduling problem for the multi-task execution and propose an efficient heuristic scheduling algorithm. Real-world experiments and extensive simulation tests show that our edge learning framework can achieve up to 70% delay reduction.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Jiangchuan Liu
Department: 
Applied Sciences: School of Computing Science
Thesis type: 
(Thesis) M.Sc.

Examining the experience of trans identity and gender transition through the lens of cisgender siblings: A phenomenological investigation

Author: 
Date created: 
2018-11-05
Abstract: 

Previous research on the transitioning process has focused on the experiences of transgender/gender nonbinary individuals and their parents, paying limited attention to the trans persons’ siblings. The purpose of this study was to examine how youth and young adults experience a trans sibling's gender identity and transition. Using qualitative methodology, eleven cisgender participants (M = 17.9; SD = 4.9; range = 14 to 34 years old) were individually interviewed in medium- and large-sized Canadian cities. Interview topics included: the participant’s role in their sibling’s transition; the impact of the transition on the participant and their family and peer relationships; and the participant’s attitudes toward services aimed at supporting themselves through their sibling’s transition. Interview transcripts were analyzed using interpretative phenomenological analysis (IPA). Ten participants completed member checking procedures to verify the accuracy of the data. Participants described wide-ranging emotional responses and overall positive attitudes toward their sibling’s trans identity and transition. Participants highlighted the importance of demonstrating to their trans sibling respect, compassion, and support. The adjustment process by the immediate family unit was regarded as manageable overall. Challenging interpersonal dynamics involving participants’ parents, extended family members, peers, and other extra familial individuals were discussed. Perspectives on the value and preferred type of structured support for siblings of trans individuals varied across participants. These findings provide novel insight into the lived experiences of siblings of trans people, thereby enriching our understanding of the transition process as experienced by the collective family unit. Study findings offer practical guidance for trans individuals, their parents, siblings, and clinicians. Strategies to improve support programs for trans individuals and their family members are addressed.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Robert Ley
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Thesis) Ph.D.

The prison experience from the prisoners' perspectives: Trauma healing within the correctional setting

Author: 
Date created: 
2018-12-13
Abstract: 

Childhood psychological trauma (CPT) has been identified as underlying generally accepted criminal risk factors and its role in the generation of criminal behaviours is profound. While psychological and behavioural impacts of unresolved CPT may continue throughout the lifetime, healing CPT is recognized as essential to rehabilitation and is possible throughout the lifetime. This dissertation examines the experiences of former prisoners of Canadian federal correctional institutions to gain an in-depth understanding of healing from CPT while in prison and during community re-entry, from their perspectives. A series of three in-depth interviews was held with 17 former prisoners who self-identified as having experienced CPT. Their experiences of CPT impacts prior to prison and their experiences of healing during incarceration and community re-entry were explored. Five primary results of this study emerged. (1) CPT impacts included chronic hyperarousal, automatic fight or flight responses, stress addiction and trauma-bonds. Prior to prison, men’s physical and psychological survival depended on their creation of autonomy and safety through threat-resistance, limited emotionality, revenge and violence, and a veneer of mask-ulinity. (2) In prison, inter-prisoner physical brutality extended pre-prison trauma; survival required hyper-mask-ulinity, which included maintaining a reputation of domination-violence, independence-power, limited emotionality and strategic relationship formation. (3) Correctional staff-prisoner interactions, based on a correctional culture of hyper-mask-ulinity, included domination, violence, emotional detachment and correctional officer solidarity that required physical and psychological brutality of prisoners. Prisoner survival depended on employment of resistance strategies, strategic relationship formation, and further emotional constriction. A correctional staff-prisoner Hyper-mask-ulinity Stand-off compounded CPT. (4) Peer-relationships and prisoner-created initiatives provided psychological and physical support consistent with factors of trauma healing, however these were experienced as ‘removal activities’ and constituted survival, and trauma-mitigating mechanisms. (5) Trauma-informed, gender responsive healing factors were experienced through relationships with community members, community-run initiatives, and experiences at Kwikwexwelhp Healing Lodge. Providing turning points in the life trajectory, these experiences facilitated initial stages of recovery from CPT, initiated growth, and enhanced rehabilitation. Consequential to the pervasive threatening environment few participants moved past Stage I of trauma recovery. Implementation of trauma-informed correctional care is recommended in Canadian federal prisons to facilitate CPT healing and enhance rehabilitation.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Nicole M. Myers
Department: 
Arts & Social Sciences: School of Criminology
Thesis type: 
(Thesis) Ph.D.

Arctic deltas as biogeochemical hotspots affecting the delivery of nutrients and dissolved organic matter to the Arctic Ocean

Author: 
Date created: 
2018-12-04
Abstract: 

The Mackenzie River and Delta were sampled during hydrologically-defined seasons in four consecutive years to assess 1) the importance of sampling during the rising limb of the flood hydrograph (rising freshet) for accurately characterizing constituent fluxes and quality, and 2) how floodplain processes affect discharge to the Arctic Ocean. Including rising freshet samples had a modest effect on annual sediment and nutrient flux estimates for the Mackenzie River (-9 to +26% difference). Nutrient quality was very different during the rising freshet, however, with relatively high concentrations of carbon-rich dissolved organic matter (DOM), phosphorus-rich particles, and nitrogen-rich inorganic nutrients. Mackenzie River DOM quality was relatively fresher, more terrigenous, and younger (radiocarbon values suggesting ages < 15 years) during the rising freshet, indicating a high proportion of recently-fixed vascular plant material. The Mackenzie was also a net absorber of carbon dioxide during the rising freshet (-112 to -258 mg-C m-2 d-1), switching to net emission after peak flood. Open water (freshet through summer) fluxes of dissolved organic carbon (1.4 Tg) and lignin (7.1 Gg) in the Mackenzie River were greater than previously reported total annual fluxes, likely due to the inclusion of rising freshet data herein. Optical parameters, and statistical relations between fluorescence components derived from Parallel Factor Analysis (PARAFAC; six in delta channels, five in delta lakes) and chemical biomarkers (e.g. lignin phenols), suggest substantial modification of DOM in delta lakes and on the floodplain during downstream transport. When incubated (14 days) under solar conditions similar to those on the floodplain, Mackenzie River DOM (isolated during peak flood) experienced photochemical changes on par with those observed in delta lakes over the entire open water period. Photodegraded DOM significantly reduced abundances but fueled per-cell growth in bacterial populations from delta habitats, indicating rapid shifts in community composition. Gradients in chemical biomarkers were related to the delta-wide gradient of lake hydrological connectivity. These results emphasize the importance of the rising freshet in accurately characterizing Mackenzie River DOM quality and carbon fluxes, and the need to sample downstream sites in lake-rich circumpolar deltas to constrain flux estimates and characterize discharge to the Arctic Ocean.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Lance Lesack
Department: 
Environment: Department of Geography
Thesis type: 
(Thesis) Ph.D.

Mid-IR waveguides and grating couplers for 2.7-2.9 μm

Author: 
Date created: 
2018-12-04
Abstract: 

Integrated silicon photonics strip waveguides and grating couplers are developed for mid-infrared (mid-IR) wavelengths at 2.7 μm and 2.9 μm. Waveguide loss is measured as a function of width for 2.7 μm light in the vicinity of a prominent OH absorption band, and a loss of less than 2 dB/cm is recorded for the 1.0 μm width waveguide. A fabrication bias metric is determined for accurately developing grating couplers at 2.9 μm on a 500 nm silicon-on-insulator (SOI), 3 μm buried-oxide substrate. A high resolution measurement scheme is motivated and measurements indicate that these devices will be capable of studying the Se+ donor spin qubit cavity coupling platform proposed by researchers at Simon Fraser University.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Stephanie Simmons
Department: 
Science: Department of Physics
Thesis type: 
(Thesis) M.Sc.

Evaluating British Columbia’s economic policies for liquefied natural gas development

Author: 
Date created: 
2018-08-30
Abstract: 

British Columbia is attempting to develop a large-scale liquefied natural gas (LNG) sector to export natural gas to Asia, with capital investments estimated to be as high as $40 billion for a single LNG plant. An alleged benefit of LNG development is increased revenue for the BC provincial government of over $27 billion. Our research investigates potential fiscal benefits for BC from LNG and the processes that were followed when developing the new LNG-related economic policies. Research methods include an analysis of relevant documents, interviews with key actors, and quantitative modeling of LNG revenue impacts. Results show that the primary objective of the fiscal mechanisms is to ensure that the LNG industry is developed in BC and maximizing the return to government is a secondary objective. Secondly, the process of developing the LNG policies did not follow best practices from a public policy perspective. Thirdly, the government’s projected incremental revenue from an LNG export industry is significantly exaggerated.

Document type: 
Graduating extended essay / Research project
File(s): 
Senior supervisor: 
Sean Markey
Department: 
Environment: School of Resource and Environmental Management
Thesis type: 
(Project) M.R.M. (Planning)

Masquerade detection: A topic model based approach

Date created: 
2018-12-19
Abstract: 

The goal of masquerade detection is to "detect" when an intruder has infiltrated a computer system by looking for evidence of malicious behaviour. In this project, I use a topic model based intrusion detection system to search for intruders within the SEA and Greenberg datasets of Unix computer commands. Using LDA topic modeling I was able to find a probability distribution for each user for both the topics over a block of commands and over each command. Using these two probability distributions and building on previous detection techniques I was able to create five different detection techniques. I describe how I created the five LDA based models and combine them to find a sixth model. All of these techniques performed on par with their non-LDA counter-parts. Therefore, combined with the reduction in dimensionality afforded by the LDA topic model, I conclude that my methods perform better than the current models.

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

Turning the page: An analysis of accessible publishing in Canada

Author: 
Date created: 
2018-12-20
Abstract: 

Unfortunately, not every Canadian book is accessible to every Canadian reader. Print disabilities (which include visual, learning, and physical disabilities) affect a significant portion of Canadian readers, and in 2018 Employment and Social Development Canada (ESDC) arranged a Working Group on Alternate Format Materials for Canadians with Print Disabilities to come up with a strategy for producing more print materials in Canada in accessible formats. The Canada Book Fund in the Department of Canadian Heritage conducted research on the topic to provide ESDC with accurate data as well as to further the Department’s knowledge of a very niche market that may be underserved. This report examines the landscape of accessible publishing in Canada: who it is for, how it is done, and how it could be done better. Following an analysis of the industry, this report provides suggestions as to how accessible publishing might be supported through the Government of Canada.

Document type: 
Graduating extended essay / Research project
File(s): 
Senior supervisor: 
John Maxwell
Department: 
Communication, Art & Technology: Publishing Program
Thesis type: 
(Project) M.Pub.

What if there is a cure somewhere in the jungle? Seeking and plant medicine becomings

Author: 
Date created: 
2018-12-10
Abstract: 

This thesis is a critical ethnographic exploration of meanings emerging at the plant-health nexus and the in-between spaces when seekers and healers meet in efforts to heal across epistemological borderlands. In both British Columbia, Canada and Talamanca, Costa Rica I investigated the motivations underpinning seeking trajectories structured around plant medicine and the experiences and critical reflections on these encounters made by healers and people who work with plant medicines. In this dissertation, I expose the contested space around understandings of efficacy and highlight the epistemological politics emphasized by participants who seek to de-center plants in popular therapeutic imaginaries, to bring out these tensions and the way they interpolate ideas about sustainability and traditional knowledge conservation. Field research was carried out in 2013 during a period of one year with the support of an SSHRC Doctoral Fellowship. Over fifty participants who work with plant medicines were consulted for this research, including healers, apprentices, herbalists, ethnobotanists, forestry specialists, and anthropologists of varying backgrounds- Afro-Caribbean, Bribri, Cabécar, Tican, American, Canadian, Hawaiian, and Anishinaabe. Their concerns around the sustainability of traditional healing practices are juxtaposed to the various ways plant medicinal identities are being constituted and instrumentalized, as subjective beings, actants, causal agents, material objects, alkaloids, teachers, relatives, or parts of “nature on the move” (Igoe, 2014). I discuss the way the burgeoning popularity of plant medicine today in some ways challenges the mainstream biomedical paradigm for thinking about medicine, as plants are re-animated with identities adopted from their cultural origins, exemplified with the popularity of ayahuasca in British Columbia. However, there is a proviso in that emerging anthropomorphisms in some instances repeat colonizing gestures even as they reflect agency and counter-hegemonic challenges, by upholding dualisms in understandings of efficacy that separate plants and healing practices from their local contexts. I argue the impactful ways thinking about plant medicine as becoming, as a verb rather than a noun, can support the sustainability of traditional healing practices and economic opportunities for the cottage industry production of plant medicine by de-centering plants in constructions of medicine.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Marianne Ignace
Dara Culhane
Department: 
Arts & Social Sciences: Department of Sociology and Anthropology
Thesis type: 
(Thesis) Ph.D.

Library is the new publisher: Establishing workflows for library-based open educational resource production programs in post-secondary institutions across Canada and the United States

Author: 
Date created: 
2018-12-13
Abstract: 

As a response to increasing costs of textbooks for college students, post-secondary institutions are exploring new methods to make learning materials affordable for students. This has resulted in a surge of interest in the concept of open educational resources (OER), or freely accessible learning materials, the most prominent of which is the open textbook. Post-secondary institutions have begun to start their own OER production programs, often staffed by librarians and run through an institutional library. As the work that was traditionally done by publishers begins to move into the academic space, new OER coordinators are searching for answers for how to successfully run an OER production program. This report is an analysis of the workflows of six OER production programs run through the libraries of post-secondary institutions in the United States and Canada, and stands a record that can be built upon in the future in the efforts to formulate a standardized approach to running a successful OER production program using Pressbooks’ book production and distribution software.

Document type: 
Graduating extended essay / Research project
File(s): 
Senior supervisor: 
Hannah McGregor
Department: 
Communication, Art & Technology: Publishing Program
Thesis type: 
(Project) M.Pub.