title: Characterizing the Mechanics of Dynamic Flow Separation on Accelerating Bodies

contributor:
Rival, David E.
Mechanical and Materials Engineering

subject:
Dynamic flow separation
Three-dimensional flow

abstract: Flow separation is present in many flows in nature and engineering. Separation is the cause of wake and stall, which increases drag and decreases the performance in many technical applications. However, examples in nature such as fish swimming or bird flight show high efficiency despite or maybe because of the induced separation. Therefore, this thesis strives to understand dynamic flow separation mechanisms in both two-dimensional and three-dimensional flows. The flows around a two-dimensional model (SD7003 foil) and a three-dimensional model (6:1 prolate spheroid) are investigated to gather insights on dynamic flow separation with an increasing degree of complexity. In particular, the influence of roughness, Reynolds number, incidence angle and acceleration magnitude is characterized. Pressure measurements and scanning stereoscopic Particle Image Velocimetry system are applied to reveal the instantaneous pressure distributions and capture the evolution of three-dimensional crossflow separation. First, the two-dimensional flow over an accelerating SD7003 foil is used to study the effects of roughness on dynamic flow separation. A biomimetic shark skin is attached and its effects on the boundary layer development are discussed. The local roughness may trigger an interaction with large-scale structures in the boundary layer for effective control. For three-dimensional flows, the interplay between pressure and crossflow structures on an inclined prolate spheroid is investigated at subcritical Reynolds numbers. The evolution of the dynamic crossflow structures is examined in relation to the acceleration magnitude and incidence angle. A high degree of 3D reorientation of crossflow vorticity is observed at larger incidence angles. The movement of the separation line is related to the vanishing of circumferential pressure gradients. Furthermore, short-lived memory effects of the flow regarding the acceleration are discussed and it is shown that the open crossflow approaches a steady state rather quickly.

abstract: PhD


title: Fairness and Ethical Analysis of Classification Models based on Facial Recognition

contributor:
Stinson, Catherine
Computing

rights: Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada

rights: ProQuest PhD and Master's Theses International Dissemination Agreement

rights: Intellectual Property Guidelines at Queen's University

rights: This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.

subject:
Facial recogntion
Algorithmic audit
AI fairness
AI ethics
Facial emotion recognition

abstract: Facial recognition is a sub-field of AI that has seen tremendous growth over the last decade both in research and commercial applications. However, there has been growing criticism from scholars in various disciplines and media on the potential harms and biases that can be present in facial recognition technologies. Algorithmic fairness scholars have proposed the algorithmic audit as a means to uncover and mitigate harms of algorithmic systems. In this thesis, I audit fairness and ethical standards of classification algorithms that are based on facial recognition. Firstly, I investigate social classification algorithms that use facial recognition to predict a social class from someone’s face. I perform an audit on an algorithm that claims to predict political orientation from faces, and show that the algorithm shows unreliability when predicting on two images of the same person before and after some presentational change such as hair, makeup, glasses, or beard. Secondly, I audit facial emotion recognition (FER) algorithms that claim to predict a person’s emotion from an image of their face. I assess three popular FER datasets and three state-of-the-art models trained on each dataset. The results show that the both the datasets and models exhibit negative biases against people of darker skin color and people who are not observed as racially white. Lastly, I reflect on the process of auditing algorithms using the FER audit as a case study. I explore ways in which audits are justified and ways in which audits fall short at addressing affective presences arising from observing potential harms. I also explore how anger and hurtfulness motivated my criticisms of FER systems, and how the audits encourage suppression of such negative emotions. I further argue that the culture of affective regulation in algorithmic fairness research limits the potential for the field to effectively address harms of algorithmic systems.

abstract: M.Sc.


title: Developing Informative and Faithful Image Captioning Systems with Compositional Generalizability

contributor:
Zhu, Xiaodan
Electrical and Computer Engineering

subject:
Compositional Generalization
Cross Modal Alignment
Image Captioning
Informative Image Captioning

abstract:
Image captioning systems aim to generate visually grounded descriptions for given images. It has been an active multimodal research problem in artificial intelligence---humans are able to understand the content of images and describe them with natural language, and we expect computers to possess such an ability. Specifically, they should resemble human-written captions with desired properties: \textit{Fidelity}, \textit{Informativeness}, and  \textit{Compositional Generalization}.
In this thesis, we attempt to realize the above goals from several different aspects: (1) Designing caption-guided visual relation graphs that can better bridge modalities to generate better captions with fidelity; (2) Connecting the generation of informative captions with natural language inference; (3) Leveraging cross-modal retrieval to generate salient information in images; (4) Improving compositional generalization ability with retrieving and editing mechanisms.
This thesis offers a set of contributions that address the challenges of generating informative and faithful captions with compositional generalizability. The first contribution is developing caption-guided visual relationship graphs that introduce beneficial inductive bias using weakly supervised multi-instance learning. Based on that a multi-task learning module is constructed to regularize the network by taking into account the explicit constraints of objects and predicates in the process of generation. The second contribution includes an estimation of the informativeness score of each caption by constructing the designated directed inference graphs based on natural language inference and the regularized learning objectives with the informativeness scores. The third contribution is investigating salient n-grams in captions and studying n-grams for regularizing the learning objectives in order to generate informative captions. The fourth contribution is a novel framework that can effectively retrieve similar image caption training instances and perform analogical reasoning over retrieved instances, which enhances the compositional generalization of image captioning.

abstract: PhD


title: The Canada Revenue Agency’s Implementation of First Nation-Canada Tax Administration Agreements: An Analysis of First Nation Sovereignty and Sui Generis Legal Status

contributor:
Walters, Mark
Cockfield, Arthur
Law

rights: Attribution-NonCommercial-NoDerivs 3.0 United States

subject:
First Nation
Sovereignty
Decolonization
Taxation
Nation
First

abstract: This thesis is anchored in a de-colonization theoretical and historical framework. It poses a narrow question in order to address a broader concern about First Nation sovereignty: Does the Canada Revenue Agency’s “same treatment” policy and practice towards First Nation tax filers and social benefit claimants comply with the Supreme Court of Canada’s sui generis common law principle, section 35 of the Canadian Constitution Act, 1982, and the United Nations Declaration on the Rights of Indigenous Peoples? This question is used as an indicator of First Nation sovereignty. A conceptual framing of sovereignty based on territorial demarcation, self-determination, and self-government is set out. Three permutations, referred to as models, of the 1648 Westphalian modern state framework are used as sovereignty reference points. A distinction is made between “internal” and “external” sovereignty. This narration leads to an observation that Modern Treaty First Nations, at best, enjoy a model-one-plus sovereignty status (similar to a municipal government). To ground the theoretical discussion, field research was undertaken with the Nisga’a First Nation of northwestern British Columbia, a Modern Treaty First Nation; the result was inconclusive. A summary observation is that First Nations must approach surplus sharing and wealth redistribution as a fluid Indigenous-values-infused policy component of their broader sovereignty vision. To bring increased rigor to their formulations, they need statistically reliable and valid assessments of the fiscal framework that underpins current First Nation-Crown relations and, at a narrow level, the impact of the Canada Revenue Agency on their sovereignty and the rights of their citizens.

abstract: PhD


title: The Rise of the Alternative Education Resource Organization By Peter J. Glinos

contributor:
Bruno-Jofre, Dr. Rosa
Education

subject:
History of Education
Alternative Education
International Education
Learner Autonomy
Democratic Education
Free Schools
Learner-Centered Education
At-Risk
School Choice
Neoliberalism
Standardized Tests

abstract: The focus of this work is to write the first history on the rise of the Alternative Education Resource Organization (AERO), an international hub for alternative educators around the globe. Each major relationship established by the organization in its formative years is traced out over the periods of AERO’s development. These major relationships include AERO’s connection to the following organizations: the Modern School Reunion, the Global Alliance for Transforming Education, the International Alternative Education Conference, Summerhill School, a network of alternatives from the post-USSR, and the International Democratic Education Conference.  In addition, the organization’s conception of “learner-centered” education is defined and placed into the context of AERO’s broader historical and organizational developments. Moreover, this work investigates how the organization’s view of “learner-centered” education shaped its understandings about the role of both the teacher and the curriculum. The former was seen as a facilitator, and the latter as organically co-constructed project between learners and their educators. Furthermore, the work discusses how “learner-centered” education was translated into AERO’s opposition towards standardized testing and the push to consolidate curriculum in the late 1990’s and early 2000’s.

abstract: M.Ed.


title: Long-Range Dependence in Stationary Gaussian Time Series: An Application to Stock Trading Volume and Realized Volatility

contributor:
Takahara, Glen K.
Economics

subject:
Long-Range Dependence
Stationary Gaussian Time Series
Stock Trading Volume
Realized Volatility

abstract:
In this thesis, we examine pure and mixed-spectra Gaussian long-range dependent time series. In chapter 2, we introduce background material that is used in subsequent chapters. In chapter 3, we propose a method to robustly estimate the variance of the sample mean for two Gaussian processes exhibiting long-range dependence (LRD): fractional Gaussian noise, fGn(H), and fractional integrated noise with Gaussian innovations, GFI(H). An important feature of the proposed method is a test statistic to differentiate between fGn(H) and GFI(H), which, under a correct decision, allows us to estimate the Hurst parameter H using the correct model specification. Theoretical properties of the test statistic are derived and numerical comparisons against existing estimators are presented. In chapter 4, we study time series characterized by hidden periodic components buried in stationary noise. We propose an approach to the problem of estimating H in processes with mixed spectra in the context of two Gaussian LRD processes: fGn(H) and GFI(H). We apply the method to synthetic periodic time series, and we show numerical results. We also examine a real data case on air quality indices based on particulate matter data from the United States and we show the effect of hidden periodic components on the estimation of H using the method. Lastly, in chapter 5, we use stock trading volume and stock realized volatility time series to illustrate the methods in chapters 3 and 4. We show the presence of hidden periodic components and, using the test statistic in chapter 3, we
propose a modelling approach.

abstract: PhD


title: Avenues of Agricultural Literacy: A Grounded Theory Model to Increase Agricultural Literacy Effectiveness

contributor:
Christou, Ted
Education

subject:
agriculture
agricultural
literacy
literate
agricultural literacy
agriculturally literate
education
curriculum

abstract: Agricultural literacy was a notion developed over 30 years ago to increase awareness of agriculture and cultivate an interest in agri-careers, ultimately to garner citizen support of the industry and secure a future workforce. However, awareness of agriculture and its importance is at an all-time low and vacancies in the agriculture industry are alarmingly high. While there are a number of reasons for this scenario, such as a departure from agrarian societies and a number of individual decisions that affect agri-career-uptake, opportunity exists for agricultural literacy efforts to have a more profound impact on these areas. The purpose of this study was to use a grounded theory approach to explore and identify themes, trends, gaps, and barriers that are helping or hindering the impact of agricultural literacy efforts and to offer theory that can inform and improve agricultural literacy program effectiveness. Initial data were collected from peer-reviewed published empirical and conceptual literature on agricultural literacy using the keyword searches “agricultural literacy,” “agricultural curriculum,” and “agricultural knowledge” in the Education Resources Information Center (ERIC) database. Additional literature was collected through concurrent data collection and theoretical sampling to situate findings in a Canadian context by filling in gaps and address arising questions. Initial, intermediate, and advanced coding were applied to 40 articles retrieved through initial data collection and 9 articles collected through theoretical sampling. Four thematic areas were identified as having potential to make agricultural literacy more effective. These four areas include definitions, goals, teaching and research approaches, and outreach confines. The avenues of agricultural literacy model is the resulting pragmatic product of this study, which serves to address the barriers identified in these areas. It offers revised definitions, identifies and links the goals to learning outcomes, curriculum, and research, and suggests agricultural literacy pair with a multiliteracies pedagogy. The final theme is addressed by suggesting advocacy for mandatory agricultural literacy courses in secondary schools with knowledgeable and experienced agriculture teachers. The avenues of agricultural literacy model can be used as a framework to guide current and future agricultural literacy programs.

abstract: PhD


title: How an Undergraduate Nursing Curriculum Influenced My Understanding and Attitude of Self-Compassion

contributor:
Galica, Jacqueline
Nursing

subject:
Nursing education
nursing students' emotional regulation
nursing students
nursing school culture
Self-compassion
Compassion

abstract: Undergraduate nursing students are experiencing high levels of perceived stress and depression, while learning to give compassion within complex clinical environments. They may benefit from learning a coping strategy to manage the difficult emotions that arise from their clinical learning experiences, which they can sustain in their practice as a registered nurse (RN). Self-compassion (SC) practice involves self-kindness and being mindful to one’s difficult emotions, while recognizing suffering is part of the shared human experience — our common humanity. Using a Scholarly Personal Narrative (SPN) methodology, I explore various life experiences, before and during undergraduate nursing education (UNE), and currently as a RN, to uncover how UNE shaped my discovery of SC. My story — written with a vulnerable heart — includes vignettes, poetry, and critical reflections supported by scholarly literature. Methods involved document analysis, unobtrusive persistent observation, mindful SC meditation, including the SPN phases: pre-search, me-search, re-search, and we-search. The transformative learning theory guided my introspective analysis revealing SC was not explicitly acknowledged, taught, or recognized during UNE, nor was SC understood to be connected to compassion —the foundation of the nursing profession. Through exploring past trauma, I discovered the aching need to find SC within my life as a nursing student and now RN, to promote regulating difficult emotions, decrease perfectionistic behaviours and underpin my current nursing practice. SC reflection and modelling by educators and clinical instructors may normalize and inspire the practice of SC within UNE to enhance professional leadership qualities and develop a sustainable artful nursing practice.

abstract: MNSc.


title: Thermal History of the Frontenac Arch in Southeastern Ontario, Canada Constrained From Low-temperature Thermochronology

contributor: Geological Sciences and Geological Engineering

subject:
Tectonics
Low-temperature thermochronology
Basement faults
Frontenac
Seismicity
Structural Geology
Canada
Grenville Province

abstract:
The Frontenac Arch is an intraplate low-relief ridge of Precambrian rocks that connects the southeastern Ontario part of the Canadian shield with the Adirondack Massif in New York State. The NW-SE trending ridge is oriented perpendicular to the major tectonic fabric of the Grenville, Appalachian, and St Lawrence rift systems. This thesis research aims to understand the building mechanism(s) and timing of this basement topography. New apatite and zircon (U-Th)/He and apatite fission track data from 19 samples collected along three transects in the Frontenac Arch provide cooling ages ranging from 183.7 - 19.5 Ma (AHe), 196.2 - 109.6 Ma (AFT), and 732.5- 144.1 Ma (ZHe). The T-t paths for the Frontenac Arch define a thermal history dominated by one stage of progressive cooling since the post-Shawinigan phase of the Grenville Orogeny (~1140 Ma) to surface temperatures by ~525 Ma after the culmination of the breakup of Rodinia. This is followed by sediment burial (~ 3-4 km) and reheating to ~160 °C with heating peaks at different times during the Paleozoic resulting in partial resetting of the ZHe dates, and a third cooling stage (0.3-0.5 °C/Ma ) starting during the breakup of Pangea and opening of the Atlantic Ocean in the Early Mezosoic.
The last pulse of cooling in the thermal models between 175-225 Ma coincides with Mesozoic normal fault reactivation documented through AFT age discontinuities in the St. Lawrence and Saguenay fault system at ca. 200 -250 Ma caused by NW-SE extension and breakup of Pangea. A younger faulting event resulting in differential exhumation is likely recorded in the Frontenac Arch along the NE-trending Rideau-Lake normal Fault between 150-190 Ma. A period of differential unroofing started at least since the Late Cretaceous and eroded most of the Early Paleozoic sediments left in the last 120 Ma, as recorded by Devonian clasts in Cretaceous diatremes and kimberlites in Montreal and Lake Timiskaming, respectively.

abstract: M.Sc.


title: Little Halophyte on the Prairie: Canadian Salt-Tolerant Plants as Remediation Tools for Salinized Soils in Western Canada

contributor:
Zeeb, Barbara
Rutter, Allison
Environmental Studies

subject:
Soil salinization
Halophyte
Remediation
Salinity tolerance
Chloride
Sulphate

abstract: In western Canada’s prairies, secondary soil salinization is contributing to groundwater contamination, soil degradation, and plant toxicity. To remediate salt-contaminated sites, a non-invasive, resource-efficient method is required. Phytoremediation with salt-tolerant plants (halophytes) is a strong alternative to conventional site clean-up methods, as plants will continuously extract salts from soil whilst improving soil structure. Three native (Bouteloua gracilis, Bouteloua curtipendula, Distichlis spicata) and three naturalized (Puccinellia distans, Atriplex patula, Chenopodium album) halophytes were grown under controlled greenhouse conditions with salt concentrations of 1500 µg/g Cl- to quantify salt extraction from contaminated soil originating from a legacy site. Based on the results obtained, A. patula, C. album, P. distans, and B. gracilis were further studied under greenhouse conditions at extremely high salt concentrations (10,500 µg/g Cl-) and accumulated 333, 176, 6.49 and 2.43 mg Cl-/shoot DW respectively. Under ideal conditions, it would take the accumulator halophyte species A. patula and P. distans ~1.3 and ~2.4 years, respectively, to remediate the site. Proof-of-concept for phytoremediation studies is needed to validate the method, hence field studies were undertaken with seven halophyte species at the legacy site using raised bed ‘mesocosms’ spiked to 10,500 µg/g Cl-. Halophyte chloride accumulation and biomass production did not significantly differ between an unamended mesocosm and one amended with 30% (by volume) triple mix. Halophyte species accumulated 0.106 – 4.27 mg Cl-/shoot DW in the field, despite climatic extremes, with opportunistic species A. fatua, T. officinale, and C. arvense accumulating even higher quantities (1.44 – 88.8 mg Cl-/shoot DW). Since recretohalophytes demonstrated minimal excretion rates in the greenhouse and the field, all three Bouteloua species, D. spicata, and Sporobolus michauxianus were grown in salt-spiked soil and excreted crystals were imaged using scanning electron microscopy. D. spicata excreted smaller salt crystals at a higher density than the larger salt crystals of S. michauxianus, and on the basis of total surface area D. spicata excreted four times as many crystals. Overall, the results of the studies undertaken indicate that the use of native and/or naturalized accumulator halophytes are justifiable in terms of efficacy to remediate salt-affected legacy sites in western Canada.

abstract: M.E.S.


title: From Wetland Wilderness to Ecological Model: Reclamations of Chongming Island, Shanghai, from 1950 to 2020

contributor:
Hill, Emily
History

subject:
Wetland drainage
Land reclamation
Mass mobilization
Food supply
Chongming Island

abstract: This dissertation investigates the transformation of social and ecological relations on Chongming Island, Shanghai from the 1950s to the 2010s. Chongming Island experienced dramatic anthropogenic environmental changes during the period, including the draining of wetlands on a large scale and a later ecological conservation program, along with the reorganization of communities on the island. Chinese Communist Party-led governments at different levels implemented policies inspired by socialism that resulted in systematic change. Irresistible state-driven campaigns reconstructed and simplified both nature and society as working tools to be managed and deployed. Wetlands were drained and transformed into state farms, completed through the mobilization of Chongming farmers, Shanghai citizens, and material resources gathered from the island’s villages. Appropriations of resources to achieve the goals prioritized by officials intensified pressures on the material world, including human resources. Tensions and resistance arose, especially when physical limits were intentionally disregarded while the interests of affected groups were discounted. Through an analytical approach to nature and humanity as a complete material world, this case study illustrates how unsustainable appropriations of natural resources and abusive demands on human productive capacities tend to occur in close association. As a contribution to Chinese history, it examines these associated impacts the “mass mobilization” that was a key principle and policy of the Mao era.

abstract: PhD


title: Understanding Access to Health Care Services Through the Stories of Women Living on a Low Income: A Qualitative Secondary Data Analysis

contributor:
Camargo-Plazas, Pilar
Nursing

subject:
Women
Health Care Access
Low Income
Socioeconomic Status
Social Determinants of Health
Narrative Inquiry
Health Inequity
Canada
Dialogic/Performative Analysis
Qualitative Secondary Data Analysis
Qualitative

abstract: In 2021, more than 2.4 million women and girls in Canada were living on a low income, which is a main social determinant of health (SDH). These women are at an increased risk for health issues, including anxiety, depression, and negative health behaviours such as smoking, physical inactivity, and unhealthy eating. Despite their risk of adverse health, women living on a low income continue to face challenges with accessing health care services. Although researchers have explored access among several subgroups of women who live on a low income, few have used a narrative approach as their methodology, and none have used dialogic/performative analysis. Furthermore, no qualitative secondary data analysis (QSDA) has been done among this population in the Canadian context. The purpose of this QSDA was to critically examine the stories about access to health care services for women living on a low income in Kingston, Ontario and to explore how the SDH (e.g., housing, food, income, transportation) affect their experiences, as reflected through a theatrical metaphor. Using interview and focus group transcripts from the primary study, five narrative threads were illuminated in the stories of five participants: sacrifice and survival; feeling powerless; loss of hope; abandonment and trust; and resilience. In this study, the complexity of health care for women was demonstrated; this involves their values about health, the barriers encountered when accessing services, and the deterrents of future system use. Increased financial support for women to promote their own health at home and in the community was highlighted as an ongoing need. Within health care settings, women indicated more compassion is needed from health care workers to encourage trust and partnership. Despite the hardships they experienced, the women continued to show strength and motivation. In this study, by further examining participant transcripts, a deeper understanding of women’s access to health care in Canada while living on a low income was developed.

abstract: MNSc.


title: Comparison of Informed and Un-Informed Shear Strength Reduction Procedures for Finite Element  Method Slope Stability Analysis

subject:
Shear Strength Reduction
Slope Stability
Finite Element Method
Geological Engineering
Geotechnical Engineering

abstract:
Geotechnical engineers commonly rely on numerical models such as the Finite Element Method (FEM) to analyze natural, civil, and mining slope stability problems. One of the goals of these analyses is typically to determine a Factor of Safety (FoS) like that obtained using Limit Equilibrium Methods (LEM). To compute the FoS, Shear Strength Reduction (SSR) techniques are commonly employed. The SSR procedure involves the systematic computation of elastic-plastic FEM slope models with differing strength parameters to solve for the FoS within a specified tolerance. This is generally achieved using a monotonically increasing or a bracketing and bisecting technique. These procedures are standard in most geotechnical FEM software packages. The advances in personal computing technology have aided the adoption of the SSR technique into engineering practice. The technique provides significant advantages over LEM techniques primarily pertaining to the lack of assumption about failure surface and forces, and the ability to compute deformation.
One of the major drawbacks of the FEM compared to LEM is the time required to complete the analysis. A single FEM SSR analysis can take hours to days to complete if using a very fine mesh. There has been limited academic literature on the topic of improving SSR procedure runtime, structurally. This thesis presents a framework for a technique called “informed” SSR. Informed SSR procedures utilize previously computed SSR stages to provide information to subsequent SSR stages to develop a better initial guess for the FEM solution. These informed procedures are compared to “un-informed” procedures included in Rocscience’s RS2 which solve each SSR stage independently of all other SSR stages. This thesis also assesses optimization of informed SSR procedures for modified Strength Reduction Factor (SRF) step sizes and constant strength parameter reduction techniques.
The cases analyzed in this thesis show that informed SSR results in drastically decreased run times when compared to analogous un-informed procedures. This is achieved whilst not drastically changing the values, such as FoS and nodal displacement, output by the un-informed procedures.

abstract: M.A.Sc.


title: Assessing polar bear (Ursus maritimus) in a changing Arctic using non-invasive DNA metabarcoding

contributor:
Lougheed, Stephen
Biology

subject:
polar bear
diet
DNA metabarcoding
blocking primer
Arctic
Canada

abstract: Dietary studies of apex predators enhance our understanding of species’ life histories, predator-prey interactions and food webs. Studies of diet over time can reveal changes in these life history and ecology that result from climate change and landscape disturbances. Polar bears (Ursus maritimus) reside at the top of Arctic food webs. Because polar bears use both sea ice and land throughout their annual cycle, they integrate trophic information from both marine and terrestrial ecosystems across their vast territories, including availability and diversity of prey species. Polar bears act as sentinels of environmental change as they are highly adapted to using sea ice as a platform for foraging and are therefore vulnerable to current and projected changes in Arctic sea ice conditions. Given that these changes in sea ice conditions are projected to alter the composition and accessibility of polar bear prey species, and the pressing need for more non-invasive wildlife monitoring strategies, this study investigates what dietary information could be retrieved from 743 polar bear fecal samples from across the Canadian Arctic using novel multi-marker DNA metabarcoding to identify Arctic birds, fish, and mammals at family- and species-level resolution. I designed two novel blocking primers specific to polar bear DNA to maximize detection of prey taxa within fecal samples. Over 8 million metabarcoding sequences were retrieved, identifying 31 prey species, belonging to 19 families, representing 14 orders. As expected, polar bears consume Arctic seal species (Phocidae), present in >70% of successfully sequenced fecal samples – more common than any other prey group. The dietary signature of taxa such as seals, small toothed whales, various seabirds, and caribou confirm previous observations of components of polar bear diet, however, the frequency of detection of several terrestrial taxa and seabird species are consumed may represent novel insights reflecting predator-scavenger relationships and shifts in the diet of the Arctic’s top predator due to climate change. My study is the first to use multi-marker, fecal-based DNA metabarcoding to provide a comprehensive assessment of the relative consumption of fish, bird, and mammal prey taxa by polar bears across the Canadian Arctic. This method offers a cost-effective, non-invasive approach for assessing regional trophic interactions and prey diversity, and reliably monitoring the diets of wide-ranging predators.

abstract: M.Sc.


title: Rényi Cross-Entropy: Properties and Closed-Form Expressions for Sources with and without Memory

contributor:
Alajaji, Fady
Linder, Tamas
Mathematics and Statistics

rights: Attribution-NonCommercial-ShareAlike 3.0 United States

subject:
Mathematics
Information Theory
Probability
Stochastics

abstract: Two R ́enyi-type generalizations of the Shannon cross-entropy, the R ́enyi cross-entropy and the Natural R ́enyi cross-entropy, were recently used as loss functions for the improved design of deep learning generative adversarial networks. In this work, we analyse the properties of the R ́enyi and Natural R ́enyi differential cross-entropy measures and derive their expressions in closed form for a wide class of common continuous distributions belonging to the exponential family. We also establish the R ́enyi-type cross-entropy rates between stationary Gaussian processes and between finite-alphabet time-invariant Markov sources.

abstract: M.A.Sc.


title: Supervised Dimensionality Reduction of Mass Spectrometry Images

contributor:
Ellis, Randy E
Computing

subject:
machine learning
dimensionality reduction
supervised learning
mass spectrometry
mcml

abstract:
In machine learning, high-dimensional data can contain hundreds or thousands of features.  Within this type of data, a small amount of meaningful information could be interspersed among an abundance of potentially irrelevant information.  Working with high-dimensional data requires answering the question: how can important information be extracted from high-dimensional data? Dimensionality reduction is a method that reduces the number of features, or dimensions, in a dataset to those determined to be important and can be an essential step to be able to extract meaningful insights from high-dimensional data.  One way this can be achieved is by projecting the data to a low-dimensional subspace that represents a combination of the important features.
Dimensionality reduction is commonly performed using unsupervised methods, but these methods may not project the data so that relationships of interest are preserved.  Supervised dimensionality reduction uses the data labels to guide the algorithm and project the data to a low-dimensional subspace while maintaining relationships that distinguish groups of interest.
In this work, we performed supervised dimensionality reduction of high-dimensional mass-spectrometry data for maximal separation of data that had distinct labels.  We assessed the quality of the dimensionality reduction by assessing the separability of the data using statistical tests and two methods of supervised classification. We compared the performance of our proposed methods to a conventional unsupervised dimensionality-reduction method.  We found that supervised dimensionality reduction projected the data to be more linearly separable than did the conventional projection.  Our results suggested that supervised dimensionality reduction can be a useful projection, prior to supervised classification, for machine learning of high-dimensional data.

abstract: M.Sc.


title: Developing New Methods to Produce Bioderived Molecules from Carbohydrates and Biomass

contributor:
Jessop, Philip, G.
Champagne, Pascale
Chemistry

subject:
Biomass conversion
Furans
Sustainable chemistry

abstract:
The growth in fossil fuel consumption and greenhouse gas emissions has encouraged the development and implementation of biobased products as replacements for fossil fuel-derived products. Specifically, bioplatform molecules have been identified as versatile molecules that can be produced from biomass, such as wood and algae, and further converted into high-value products. The use of bioplatform molecules is anticipated to provide a renewable alternative for many petroleum-based products, including fuels, specialty chemicals and monomers.

Two widely studied bioplatform molecules are 5-hydroxymethylfurfural (HMF) and 5-chloromethylfurfural (CMF) due to the versatility of their hydroxyl/chlorine, aldehyde and furan ring functionalities that can be utilized for further conversion. However, some challenges have emerged with the use of both molecules. HMF and, to a lesser extent, CMF are easily converted into humins, an unwanted polymeric side-product, during synthesis and storage. Additionally, HMF can be difficult to isolate due to its high polarity, and CMF synthesis methods, unfortunately, use halogenated solvents. With these challenges in mind, this work has investigated alternative routes to produce bioproducts.
A less environmentally harmful CMF synthesis method and using CMF as a substrate were studied. A new method for the production of CMF using a semi-batch flow system was developed, where toluene and cyclopentyl methyl ether were explored as successful alternatives to the chlorinated solvents currently used in obtaining high yields of CMF. To investigate the benefits or drawbacks of CMF compared to HMF, CMF was studied as a substrate in a variety of reactions to produce biofuel precursors and monomers. Improvements in the CMF synthesis method and benefits of its use as a substrate were demonstrated.

Cascade reaction methods were studied for synthesizing select bioproducts from fructose to produce and use HMF in situ without requiring its isolation. The cascade Ritter reaction was the most successful; therefore, its environmental impact was also assessed. Cascade reactions can provide a less environmentally and economically costly route to bioproducts directly from carbohydrates.
This thesis demonstrates methods that have been developed to overcome the challenges encountered using HMF and CMF for bioproduct synthesis, while also establishing successful bioproduct synthesis reactions from both CMF and fructose.

abstract: PhD


title: Data Allocation and Benchmarking in Parallelized Mobile Edge Learning

contributor:
Hassanein, Hossam
Computing

subject:
Machine learning
Edge computing
Distributed learning
Neural networks
Mobile edge learning
Federated learning
Parallel learning
Resource allocation

abstract: Democratizing Edge Computing (EC) by tapping into the copious yet underutilized computational resources of IoT devices can facilitate the use of Mobile Edge Learning (MEL). In MEL, it is important to address system heterogeneity in a way that minimizes staleness to improve learning accuracy, particularly in Parallelized Learning (PL). To do so, a centralized data allocation approach is typically used. However, this approach tends to overlook the privacy of learners, since learners’ capabilities are assumed to be known beforehand by the orchestrator. In this context, we propose the Data Allocation via Benchmarking (DAB) scheme. DAB is a decentralized data allocation scheme that eliminates staleness and achieves a certain Quality of Service (QoS), while preserving the privacy of learners. DAB also introduces a novel method to enable each learner to accurately estimate its own hardware characteristics via benchmarking. In addition, we propose the Minimize Expected Delay (MED) scheme. MED enables multi-task allocation for PL under uncertainty in learners’ capabilities. Given the state probabilities of learners, MED makes uncertainty-aware decisions by formulating the data allocation problem as an Integer Linear Program (ILP) that aims to minimize the sum of the maximum expected delay of all tasks, while abiding by certain training time and budget constraints. Furthermore, we propose a novel MEL framework, called Axon, to foster testing on real testbeds. Extensive performance evaluations on a real testing environment show that DAB outperforms a prominent representative of the centralized data allocation approach by up to 12% and 26% in terms of loss and prediction accuracy, respectively. In addition, the proposed benchmarking scheme yields an 83% reduction in benchmarking error compared to a prominent baseline scheme. Performance evaluations also show that MED outperforms an uncertainty naive baseline by up to 10% and 42% in terms of training time and data drop rate, respectively.

abstract: M.Sc.


title: Vibrio cholerae's Largest Adhesin and How to Block It

contributor:
Davies, Peter
Biomedical and Molecular Sciences

subject:
Adhesins
RTX
Vibrio cholerae
Biofilm

abstract:
Numerous species of pathogenic Gram-negative bacteria produce repeats-in-toxin adhesins to bind to host cells and subsequently form biofilms during a bacterial infection. These long, membrane-anchored proteins typically contain four functional regions: A small N-terminal membrane-retention module, a long repetitive extender region, followed by a ligand-binding region, and a non-cleavable C-terminal secretion signal. Flagellum-regulated hemagglutinin A protein is a repeats-in-toxin adhesin of Vibrio cholerae, the main causative agent of cholera disease. Previous gene knockout studies showed the adhesin is required to bind to chitin, erythrocytes, epithelial cells, and to form biofilms. Using bioinformatic approaches, a peptide binding domain and sugar-binding domain were identified adjacent to a domain of unknown function. The objective of this thesis project was to determine the structures and functions of the sugar-binding and unknown domains.
A recombinant 42-kDa construct spanning the sugar-binding domain and unknown domain was expressed, purified, and probed by glycan micro-array screening, which showed the two-domain protein favours binding mammalian fucosylated glycans, some of which are characteristic of red blood cell markers and intestinal cell epitopes. Isothermal titration calorimetry further showed the construct can bind soluble L-fucose with a 0.7:1.0 stoichiometry and an affinity of approximately 21 µM. This recombinant protein construct lysed red blood cells on binding to their membranes. Both membrane binding and hemolysis were blocked by the addition of soluble L-fucose. Using AlphaFold, the domain boundaries of both domains were shown to be slightly shorter than previously predicted, and the unknown domain was recognized as a split Ig-like domain that can assist in projecting the ligand-binding domain towards its target. The AlphaFold-predicted structure fits well within the molecular envelope structure iii obtained from BioSAXS. A 40-kDa protein orthologue construct from Aeromonas veronii was also expressed and purified. It appeared more stable than the V. cholerae protein, had a 1:1 stoichiometry in L-fucose binding, and was predicted to fold to the same way as the V. cholerae two-domain construct. By studying the sugar-binding domain architecture and identifying glycan ligands, inhibitors targeting the adhesin can potentially be developed to block or disrupt infection by V. cholerae, as well as by other pathogenic bacteria with similar adhesins.

abstract: M.Sc.


title: We Learn Together: Fostering a Love for Anishinaabemowin in the Hearts and Classrooms of Urban Indigenous and Non-Indigenous Students and Teachers

contributor:
Morcom, Lindsay
Education

subject:
language revitalization
community
Indigenous

abstract:
Indigenous languages across Turtle Island, now known as North America, are in danger of becoming extinct. Gallery (2016) states that currently, only 60 of the previous 300 Indigenous languages that existed are being spoken. McIvor (1998) explains that language loss does not have to be a personal experience for one to feel the effects of it and that in fact language loss can be passed down through generations. The dire state of Indigenous languages across Canada is a direct result of historical and current laws and policies designed to assimilate Indigenous people’s languages to future generations, resulting in a significant decline of languages over time.
Indigenous communities are working to save their languages through various methods including, but not limited to, immersion programming, language nests, and language programming at all levels of educational institutions. With this work in mind, the United Nations declared 2022-2023 the International Decade of Indigenous Languages, highlighting the need to preserve the Indigenous languages that are disappearing at an alarming rate (UNESCO, 2022). The purpose of this study is to examine the impact of an Anishinaabemowin pilot (language programming) in local schools on urban Indigenous youth and to observe how access to language programming in schools can contribute to Indigenous language revitalization efforts and cultural pride and confidence in Indigenous learners. The research was informed by four research questions: 1.) How does the language program benefit both Indigenous and non-Indigenous students? 2.) How can naturalizing Indigenous knowledge deconstruct the Eurocentric belief of ‘what is curriculum’? 3.) How can Indigenous and non-Indigenous community members support further language learning in our communities to create more fluent speakers? 4.) In what ways can we encourage teachers to continue with language revitalization work and teaching Indigenous content when the pilot is over? This study was conducted using a qualitative approach to research and integrated both Eurocentric qualitative research methods as well as Indigenous research methods which included both a community-based research approach and use of the conversational method. Data was collected through an Indigenous approach of a talking circle with community partners who were responsible for the creation and implementation of the Anishinaabemowin pilot. Data analysis indicated that there is a need for Indigenous language programming to continue at a school-based level and a desire from the Indigenous community to see educators continue to integrate Indigenous ways of knowing, being, and doing as well as Indigenous languages into their classroom communities. Findings of this study will be of interest to Ontario school boards and Indigenous communities looking to implement language programming in local schools.

abstract: M.Ed.


title: Influence of Ice-covers on Stream Hydraulics and Geometric Characteristics of Alternate Bars in Rivers: an Experimental Study

contributor:
da Silva, Ana Maria Ferreira
Civil Engineering

subject:
Alternate bar length and height
Ice-covers
Velocity profiles
Velocity-dip phenomenon

abstract:
The thesis consists of two parts. In the first part (Chapters 2 and 3), the effect of ice-covers on stream hydraulics and especially the vertical velocity profile is reviewed (Chapter 2) and analyzed through a series of laboratory experiments involving both open channel and ice covered flows (Chapter 3).

Chapter 3 aims to address the following research needs (1) examine and characterize velocity profiles in ice covered streams having a gravel bed, (2) evaluate existing equations (namely the two-power law by Tsai and Ettema 1994 and the equation by Guo et al. 2017) for the vertical velocity profile in covered flows, and (3) evaluate the modified log-wake law by Guo (2014) which is applicable to uncovered streams (open-channel) with smooth beds affected by the velocity-dip phenomenon. Use is made of simulated ice covers. The measured velocity profiles under  the simulated ice covers were found to be in agreement with the general findings by other authors. The two-power law by Tsai and Ettema (1994) and the equation by Guo et al. (2017) were able to reproduce the velocity profiles resulting from the present measurements reasonably well, with the equation by Guo et al. (2017) yielding a more uniform distribution of the data around the best agreement line. For the open channel flows over smooth beds, the modified log-wake law by Guo (2014) was found to not be appropriate. A new empirical adjustment was proposed.

Chapter 4 deals with the effects of ice-covers on the length and height of the bedforms known as alternate bars. The fundamental question this research aims to answer is whether or not the geometric characteristics of alternate bars are altered in the presence of an ice cover, and if yes, by how much? It was found that the height and especially the length increased with the presence of an ice cover. This chapter hypothesizes that in covered flows the effective width-to-depth ratio that determines the length and height of the bars may be that associated with the height of the lower layer (height of maximum velocity), instead of the total flow depth.

abstract: M.A.Sc.


title: Wind-Driven Dynamics and Numerical Modelling of Temperature Structure in the Nearshore Region of Lake Ontario

contributor:
Boegman, Leon
Shore, Jennifer
Civil Engineering

subject:
Physical Limnology
Wind-Driven Dynamics
Numerical Modelling
Temperature Structure
Mixing
FVCOM
GOTM

abstract: Physical observations in Lake Ontario during 2010 were analyzed and numerical models were applied to study the seasonal temperature structure in the lake and assess the turbulence closure schemes that are used within numerical ocean models to parameterize mixing and dissipation at sub grid scales. These schemes require calibration and often have difficulty simulating and maintaining the sharp vertical thermal gradients. In Chapter 2, wind, lake temperature and current data was analyzed to characterize the effect of the imposed wind stress on the momentum balance of the lake, motion of the thermocline, and bed processes such as resuspension and dissipation. The effect of the wind was clearly observed in the residual pressure gradient from the momentum balance. Large magnitude positive pressure gradients preceded downwelling of the thermocline while weak positive and negative pressure gradients preceded upwelling. While it cannot be stated definitively that internal Kelvin waves did not contribute to large perturbations of the thermocline, the observations indicated that the motion of the thermocline-shelf intersection was primarily driven by the pressure gradient initiated by the local wind forcing. The stability of the thermocline was affected by the direction of motion of the thermocline shelf intersection, producing temperature overturns during upwelling events and while the temperature transitioned from upwelling to downwelling behaviour. In Chapter 3, The Finite-Volume Community Ocean Model (FVCOM) using the General Ocean Turbulence Model (GOTM) for vertical mixing was tested and calibrated extensively with the goal of reproducing the thin seasonal thermocline present in observations. Total temperature RMSE was reduced following adjustment of internal coefficients and the inclusion of new stability functions but the thermocline remained significantly more diffuse than observed, even while underestimating the diffusivity of heat by several orders of magnitude. In Chapter 4, GOTM was tested as a standalone model to investigate its performance outside of FVCOM. GOTM produced realistic values for the turbulent macro lengthscale, dissipation of turbulent kinetic energy, and diffusivity of heat indicating that the vertical mixing parameterization by GOTM is not the root cause of overly diffuse temperature reproductions in FVCOM.

abstract: PhD


title: Last Out of Beirut Turn off the Light - A Chronicle of Beirut Through its Public Spaces

contributor:
Aziz, Sylvat
Cultural Studies

subject:
Beirut
Storytelling
Resistence
Public space
Memory
Community

abstract: I introduce Beirut as my site of research. Many scholars have designated it as a “divided” city after fifteen years of Civil War (1975-1990). I view my hometown in a different light, where the population might finally be beginning to resist the dominant hegemony. I research public space in Beirut post-war, and how they either fostered cohesion or was exclusionary to reconciliation between the divided societies that reside in the city. I investigate how urban space has been used both to continue the hegemony of the ruling regime, and to become the site of protest and contestation where public space is re-appropriated. Through inhabitants’ narratives and oral histories, I research people’s place memories and how they are associated with certain recollections, histories, longings, and feelings - pre-war, and post-war. This study is a qualitative exploration of everyday life in Beirut, utilizing a multiple method approach with interviews, surveys, maps, participatory observation, personal illustrations and photographs, in conjunction with varied archival material and historical photographs. The research’s main aim is to understand what can be done to change the “divided” narrative of Beirut through its public spaces incorporating the intersecting notions of public space, governmentality, and dissent in Beirut.

abstract: PhD


title: “you are part of the river, even if you have forgotten it”: The Politics of River Writing in Contemporary Indigenous and Canadian Literatures

contributor:
Macfarlane, Heather
English Language and Literature

subject:
contemporary literature
environmental
ecocritical
decolonial literature
Indigenous literature
canadian literature
decolonization
river writing
environmental literatures
allyship

abstract:
My dissertation examines the complex and layered representations of rivers within Contemporary Canadian and Indigenous literatures, revealing the important intersection between rivers, ecocriticism, and Indigenous cultural resurgence. Using criticism by scholars such as Leanne Simpson, Glen Coulthard, and Astrida Neimanis, I examine the different positionalities and voices at the heart of primary texts such as Katherena Vermette’s river woman, Rita Wong’s undercurrent, and Christine Stewart’s Treaty 6 Deixis. Moving between Indigenous, European settler, and diasporic writers currently living on the lands known as Canada, I investigate the practice of ethical allyship and the important connection between literature and life, or art and praxis. As such, my work is just as concerned with politics, and emphasizing the ambitions for decolonial praxis central to many of the works, as it is with examining more conventional literary aspects of river writing. My thesis situates various urgent literary and political issues and focalizes these concerns within the site of Canadian rivers. By putting these texts in conversation, I analyze rivers and their relationships to broader political, cultural, and literary discourses such as second-wave ecocriticism’s preoccupation with incorporating Indigenous knowledges and their sustainable relationships to the land into contemporary environmentalism; decolonization and its re-situation into original political and cultural contexts; the water crisis and the physical and cultural centrality of water to both Indigenous and settler cultures; and contemporary Indigenous Cultural resurgence. Ultimately, cultural representations of rivers reveal that decolonization is inextricably bound to any movement toward ecological sustainability.
My dissertation treats the rivers that I discuss as both real—physical, geographical, chemical, environmental, tangible—and symbolic—metaphorical, symbolic, cultural, spiritual, abstracted, theoretical. By keeping a consistent focus on cultural positionalities in my analysis of these texts and their relationship to systems of power, I contend that rivers are a complex literary site because they are important to Indigenous, settler, and diasporic cultures. As such, I determine that rivers are not only a key environmental concern, but they also represent a key dialogic space since they are central to the cultural and social narratives of Indigenous Peoples and settlers alike. Ultimately, I argue that understanding rivers through a more nuanced, non-western, and decolonial lens can help facilitate opportunities for environmentally sustainable and socially just futures. Guided by words like those from Fred Wah, who says “you are part of the river, even if you have forgotten it,” my project seeks to expose the ways in which examining our relationships to rivers can help to create decolonial and sustainable futures.

abstract: PhD


title: Radical Interventions and Resistant Black Looks: Wangechi Mutu’s Transgressive Black Female Subjectivity

contributor:
Kennedy, Jennifer
Art History

subject:
Black Sexual Politics
Black Studies
Black Feminism
Black Feminist Thought
Art History
African Diaspora
Contemporary Art
Black Gender Ideology
Arts and Culture
Wangechi Mutu
bell hooks
Oppositional Gaze
Gaze Theory
Critical Race Theory
Kenya
America

abstract: The 2000s were a significant period in the development of Kenyan-American artist Wangechi Mutu’s critical praxis. During this time, Mutu utilized collaging as a means of facilitating complex discussions about the representation of the black female body in popular culture. Her work, which takes into account the multifarious aspects of the imperial gaze and its influence on personal and collective identity proposes hybridity as a form of radical intervention and a way of (re)imagining blackness. The works selected here looks at how Mutu employs an oppositional gaze as defined by critical theorist bell hooks to interrogate and dismantle disparaging narratives put forth about blackness and black female subjectivity in particular in mainstream culture and popular discourses. The oppositional gaze as a means of creating transgressive black images/black looks in Mutu’s work shows how contemporary black sexual politics are tethered to historically derogatory assertions and stereotypes about blackness that reinforce the continued social and political oppression of black communities. During the 2000s, especially in the early to mid-2000s, Mutu produced works that physically and ideologically disrupted hegemonic Western tropes of blackness using collaging as an artistic strategy. The intimate and complexities of Mutu’s collages at this time created an opening for examining the development of defining and depicting the black female body and its integral relation to black sexual politics. My Master’s Thesis examines three of Mutu’s works in relation to the emergence of discourses of black feminism and Black sexual politics during the 2000s. In doing so, this thesis comparatively analyzes: 1) how the concept of the black female body has traditionally been inscribed and intellectually defined through Western visual culture to produce perspectives that uphold the social and political marginalization of black individuals; and 2) how Mutu’s work problematizes this one-dimensional view of black people and bodies through her art. The specific artworks included here reveal the adaptation of black feminist strategies by Mutu as a response to ongoing defamatory stereotypes about blackness. The works also demonstrates how Mutu simultaneously fractures her viewer’s gaze and encourage a critical view of the images’ original meanings using the oppositional gaze.

abstract: M.A.


title: The Invisibilisation of African Canadian Histories in Public Memory: The Heritage Designation of 221-223 King Street East & The Black Absented Presence of Joseph Gutches in Kingston, Ontario, Canada

contributor:
McKittrick, Katherine
Prouse, Carolyn
Geography and Planning

subject:
Black Absented Presence
African Canadian Histories
Public Memory
Heritage Designation
Kingston Ontario Canada

abstract:
This work seeks to address the invisibilisation of African Canadian histories in relation to constructions of public memory in Canada. I center my research around the erasure of Joseph Gutches’ historical presence as a black enslaved man from the heritage interpretation of 221-223 King Street East in Kingston, Ontario, Canada. I develop this research topic out of a response to the centering of Joseph Gutches’ historical narrative through the virtual memory project entitled Stones Kingston. The emergence of Joseph Gutches’ historical presence acts as a counter-narrative that disrupts the dominant white settler remembrances associated with 221-223 King Street East. I use the memory producing content presented by Stones Kingston as evidence towards the invisibilisation of black Kingstonion history working through the “official” cultural heritage interpretation and designation of 221-223 King Street East under the Ontario Heritage Act.
   From a geographical perspective, I engage with the conceptual and theoretical groundwork provided by the sub-discipline of black geographies to attend to the denials of black Canada as enduring and historical. I draw upon overlapping and intersecting geographies of black enslavement to inform the narrative building I employ to render visible Joseph Gutches’ historical presence and the processes of invisibilisation. To address my research problem, I complete a thematic analysis of archived material pertaining to the documented presences of Joseph Gutches and his slaveholder(s). These preservations of tangible records provide insights into the characteristics of colonial memory production and its relationships to traditional heritage and public memory. In combination with the strategies listed above, I analyse the architectural dominance of 221-223 King Street East, acknowledging the site as a historical landscape belonging to a conservation district and as a series of landscapes connected by hegemonic meanings protected under cultural heritage laws. I conclude my research by discussing the interactions between ideological, racial, socio-cultural, and spatial practices that construct the absented presences of black Canadian historical peoples from the heritage interpretations of historical sites in Canada. I finalise my conclusion by introducing how blackness and early black Canada can be remembered amidst the terrain of archival and traditional heritage-based productions of public memory.

abstract: M.A.


title: Interactive Effects of Elevated Salinity and Heatwaves on Freshwater Zooplankton: From Community Ecology to Individual Physiology

contributor:
Arnott, Shelley
Biology

subject:
Road salt
Climate change
Multiple stressors
Rapid evolution
Mesocosm
Daphnia
Lake
Synergism
Antagonism
Simultaneous
Asynchronous
Population
Community
Physiology

abstract: Freshwater ecosystems are being disturbed by multiple new and ongoing stressors that often occur simultaneously or asynchronously. Among those stressors, fluctuations in salinity levels and heatwaves that are becoming more frequent and intensified can individually and interactively impact freshwater organisms. However, we lack a good understanding of their joint impacts and how the temporal fluctuation of these stressors affects the impacts. To help fill this gap, I conducted field and lab experiments using freshwater zooplankton to investigate their interactive effects on communities, populations, and physiological conditions. My results show that the joint effects of elevated salinity and heatwaves vary at different scales: antagonism (i.e., the joint effect is less than the sum of each individual effect) at the community level, mainly driven by species compositional changes; no interaction at the population level, caused by evolutionary changes; synergism (i.e., the joint effect is greater than the sum of each individual effect) at the individual level, due to physiological responses. I also found that the interactions between stressors change with different time intervals between them, because of the legacy effect of the prior stressor or population and community recovery processes. My work contributes to the area of multiple-stressor interaction by showing the joint effects of elevated salinity and heatwave conditions at different levels of biological organization. The findings demonstrate that ecosystem management and restoration efforts that commonly just address the effect of a single stressor should consider prior stressor exposure, and the combined effects of two asynchronously occurring stressors can be more accurately predicted when accounting for the time intervals between the exposures. Moreover, the upscaling of lower-level (physiological and individual) results to the community or ecosystem level, which is sometimes used in the management of ecosystems, should be done with caution since there can be inconsistency in responses across ecological scales.

abstract: PhD


title: Structure-Activity Relationships in Adhesins from Environmental Bacteria

subject:
Bacterial adhesin
Protein structure
Protein function

abstract:
The aggregation of bacteria into the form of biofilms is a measure of their success in colonizing biotic and abiotic surfaces. Biofilm communities provide the sheltering bacteria with resistance against biocides like antibiotics, and physical disruption from forces like shearing and abrasion, as well as opportunities to swap beneficial DNA sequences. Bacterial biofilms can be harmful as in tooth plaque or chronic infections, or they can be beneficial as in promoting plant growth by excluding harmful microorganisms. Bacteria use adhesion proteins (adhesins) to initiate the interaction with host surfaces. Characterizing these proteins may provide opportunities to inhibit pathogenic biofilms and reinforce beneficial ones.
The purpose of this thesis was to investigate the structure and binding partners of ligand-binding domains from select repeats-in-toxic (RTX) adhesins, and to find novel domains with similar functions. The examples pursued here include: 1) The large adhesion protein (Lap) from the rhizobacterium Pseudomonas fluorescens, which contains a peptide-binding domain called vWFA domain. The domain, being different from the orthologs in eukaryotes, contains an extra insert region adjacent to the metal-binding site. Structural alignment with vWFAs from other bacterial species indicated that this region might affect ligand selection. 2) A sugar-binding PA14 domain was recognized in Pseudomonas fluorescens Lap as a highly conserved ortholog of the one from Marinomonas primoryensis ice-binding protein. To establish the importance of the D-cis-D motif during biofilm formation, the double aspartates in the binding site were mutated to alanines, which eliminated the domain’s ability to bind glucose. Lastly, 3) The large adhesion protein from the oil-degrading bacterium Marinobacter hydrocarbonoclasticus contains a second sugar-binding PA14_2 domain besides the previously characterized PA14 domain. A recombinant version of the second ligand-binding domain was produced in E. coli. Its elution during Superdex 75 size-exclusion chromatography was retarded, suggesting it might have a sugar-binding ability. Glycan array analysis showed that the domain had a preference for binding carbohydrates extracted from Proteus mirabilis. This result might help identify the type of organisms on which the oil-degrading bacteria form biofilms.

abstract: M.Sc.


title: Performance of Short and Slender Ultra High Performance Concrete filled Steel Tube and Double Skinned Columns

contributor:
Fam, Amir
Civil Engineering

subject:
UHPC
UHPC-filled steel tube
UHPC-filled double skin steel tube
Composite column

abstract:
This thesis examines the axial compression load-carrying capacity of ultra-high performance fiber reinforced concrete (UHPC)-filled steel tubes (UHPC-FSTs) and double skin systems, including short and slender columns.  The first part of the study investigates experimentally and numerically the axial loading behavior of 135 MPa UHPC-filled double skin steel tubular columns (UHPCFDSTs).  A total of 37 short stub columns were tested, including totally filled control tubes and tubes filled with normal- and high-strength (NSC and HSC) concrete.  The study examined the effects of outer tube diameter-to-thickness (Do/to) ratio and inner-to-outer tube diameter ratio on the axial capacity of UHPCFDSTs. A nonlinear finite element model using the computer program LS-DYNA was also developed and verified.  The experimental results were compared against the Canadian CSA (CAN/CSA) S16:19 code provisions which were found to overestimate the axial capacity by 12-56%. A modification factor was developed and is recommended to be introduced in the code equation.

The second part of the study investigates slenderness effects in UHPC-FST columns.  A robust three-dimensional nonlinear finite element model was developed using LS-DYNA to simulate the slender columns under concentric axial compressive loads and was validated using a large experimental database. An extensive parametric study was then performed, varying slenderness ratio (kL/r) based on column length (L) where r is the radius of gyration, diameter-to-thickness ratio (D/t) of the steel tube, effective length factor (k), and steel yield strength (fy). The CAN/CSA S16:19 code provisions grossly underestimated the load-carrying capacity of slender UHPC-FSTs by up to 48% at k= 2.0.  A modification to CAN/CSA S16:19 equation was proposed based on multiple regression analysis of the results of the parametric study.

abstract: M.A.Sc.


title: Detailed Design and Validation of an eVTOL Aircraft Wing Using Multi-Material Topology Optimization

contributor:
Kim, Il Yong
Mechanical and Materials Engineering

subject:
Multi-Material Topology Optimization
Finite Element Analysis
Personal Air Vehicle
Urban Air Mobility

abstract: As rapid urbanization increases traffic congestion in densely populated areas, the emerging industry of electric vertical takeoff and landing (eVTOL) vehicles aims to develop new modes of flight-based intracity transportation. These vehicles strive to incorporate features present in existing airplanes and rotorcraft, while introducing innovative concepts to reduce noise pollution, eliminate reliance on fossil fuel-based power systems, and improve the overall efficiency of short-range air travel. While promising, the configurations of eVTOL vehicles are unlike any existing aircraft and will require creative solutions to develop safe and efficient internal structures. This thesis demonstrates the advantages of computational design tools such as multi-material topology optimization (MMTO) and finite element analysis (FEA) when applied to primary aircraft structures with unorthodox geometries and loading requirements, without resorting exclusively to uncertain traditional configurations. The design process exemplified was based on a conceptual eVTOL wing body with numerous suspended auxiliary propulsion components and integrated wing-fuselage attachment lug. An initial finite element model of the wing geometry was created with an assortment of aerodynamic and propulsion-based ultimate loading conditions, on which compliance minimization MMTO was conducted to identify ideal lightweight material distributions considering various combinations of isotropic metallic and anisotropic CFRP materials. The high-performance combination of titanium, aluminum, and 8552S-AS4 composite was selected for detailed CAD reinterpretation of the MMTO material layout to develop individual components with incorporated features for manufacturing, joining, and assembly accessibility of the internal structure. A finite element model of the reinterpretation was produced to obtain failure, stress, and force data under the prescribed loads. The composite components experienced minor intermediate ply failure, while all metallic components and fasteners remained below their respective yield stress limits. At a final mass of 145.9 kg, this MMTO-driven design met all validation criteria, justifying the application of MMTO for complex and unconventional primary aircraft structures.

abstract: M.A.Sc.


title: Techniques and challenges in low-mass dark matter searches using CDMS style detectors

contributor: Physics, Engineering Physics and Astronomy

subject:
Dark matter
Direct detection
Cryogenics

abstract:
Astronomical and cosmological observations suggest that roughly 85% of matter in the universe is in the form of non-luminous dark matter that interacts predominantly via gravity. The preferred explanation is that dark matter is comprised of one or more new particles, which may solve open questions in particle physics. Direct detection experiments look for interactions of galactic dark matter in sensitive detectors using a variety of technologies, including: cryogenic solid state detectors, time projection chambers with liquid noble elements, and bubble chambers with superheated fluids. The cryogenic operating temperatures of solid state detectors afford these devices excellent energy resolutions and low energy thresholds, providing sensitivity to low-mass dark matter particles. The Super Cryogenic Dark Matter Search (SuperCDMS) is a direct detection experiment that uses cryogenic semiconductor detectors instrumented with superconducting transition edge sensors. The first phase of SuperCDMS took place at the Soudan mine in Northern Minnesota, and preparations are being made for the next phase at SNOLAB in Sudbury, ON. Prior to the completion of SuperCDMS SNOLAB, the detectors will be
tested in the neighboring experimental bay at SNOLAB in the Cryogenic Underground TEst (CUTE) facility. This thesis describes contributions to the design and construction of CUTE and testing data from SuperCDMS detectors in this facility. As well, results of a dark matter search using data from SuperCDMS Soudan, and results from a prototype detector operated at the University of Massachusetts Amherst will be presented. These data sets provide constraints on axion-like particles and dark photons with masses as low as 40 eV, and thermal relics with masses down to 40 MeV. When probing such low dark matter masses with cryogenic detectors, several experimental and analytical considerations must be taken into account, which will be detailed in this thesis.

abstract: PhD


title: Topology Optimization with Void Accessibility Constraints for Additive Manufacturing

subject:
Topology Optimization
Additive Manufacturing
Void Accessibility
Void Restriction

abstract:
The innovation of additive manufacturing has allowed for the production of complex geometries not previously able to be manufactured easily or at all. While additive manufacturing was formerly thought of as only a rapid prototyping tool, recent improvements have increased the applications of additive manufacturing in a number of fields. One of these uses is manufacturing components designed using computational optimization methods like topology optimization. However, while additive manufacturing has less constraints than traditional manufacturing, it is not completely without constraints. In order to additively manufacture components designed with topology optimization, optimization results generally must be modified to remove voids from which support material and unused powder or resin can not be removed. These modifications cause a reduction in the optimized performance. This reduction in performance can be minimized by considering the void accessibility during the optimization itself.
This work presents a novel methodology for void restriction in topology optimization considering void accessibility. The constraint is formulated in such a way that it can identify accessibility paths of varying widths with no restriction on finite element mesh type. Additionally, the constraint allows the designer to choose the number of accessibility directions used, giving them more control over the trade-off between increased design freedom and performance, and decreased computational efficiency and ease of manufacturing. The constraint is demonstrated on 2D and 3D academic test cases which demonstrate the effectiveness of the methodology. In all cases, fully accessible designs were generated with compliance increases up to only 55%.

abstract: M.A.Sc.


title: Anion Effect on CO2 Electrochemical Reduction on Cu

contributor:
Dinh, Cao Thang
Chemical Engineering

subject: CO2 electrochemical reduction

abstract: As cost of renewable energies continues to decrease, CO2 electrochemical reduction (CER) to value added fuels and chemicals is now a foreseeable possibility. Multi-carbon (C2+) products, such as ethanol and ethylene are especially promising due to their high economic potential. However, to date, all catalysts that produce C2+ products at an industrially relevant current density contain a significant amount of copper, which is intrinsically challenging in CER selectivity and stability. To improve performance, significant research effort was made to improve copper catalysts via techniques such as morphology engineering and incorporation of various organic and metallic additives. Nonetheless, CER is well known to be a delicate system, and catalyst optimization by itself is insufficient in achieving performance. Instead, other CER components such as catalyst support, reagent gas feed, and electrolyte are all essential contributors to a successful system. For example, electrolyte pH and cation have both been shown to exert significant effects on CER in both theorical and experimental studies. Nonetheless, comparatively, electrolyte anion receives much less literature attention, and its effect is insufficiently understood. Although CER literature typically chooses from a small pool of anion type, namely HCO3-, SO42-, Cl-, Br-, or I-, their selection is often poorly justified and lacks a rational basis. Therefore, this thesis reports how anion affects selectivity and stability of CER on polycrystalline copper. Via modelling, experiments, and in-situ measurements, the investigation reveals that anion, via salting out effect, modulates CO2 solubility and availability, which in turn affect catalyst performance. Specifically, copper stability is especially affected by anion. Altering anion type and anion concentration causes a multi-fold variance in stability time (halides > bicarbonate > sulfate; low concentration > high concentration). On the other hand, at high current densities (100 – 250 mA/cm2), CER selectivity is much less sensitive to changes in anion, only showing a difference in performance under extreme anion conditions. By linking anion, CO2 availability, and CER performance, this thesis provides a rational basis for future anion selection, and highlights CO2 availability’s importance in CER processes.

abstract: M.A.Sc.


title: EXAMINING THE EFFECTS OF ENDOTHELIAL BMPR2 LOSS ON ANGIOGENESIS IN MURINE METASTATIC LUNG TUMOURS

contributor:
Ormiston, Mark
Translational Medicine

subject: cancer

subject: angiogenesis

subject: endothelial cells

subject: bmp9

subject: bmpr2

abstract:
It is proposed that bone morphogenetic protein 9 (BMP9) may play a role in cancer development and tumour angiogenesis; however, its role has not been fully elucidated. Under normal conditions, BMP9 acts as a vascular quiescence factor (David et al., 2008); signalling through Type I and II receptors, including Bone Morphogenetic Protein Receptor II (BMPR-II) in the endothelium. However, these effects are highly context dependent. Previous reports examining the role of BMP9 in cancer have shown that BMP9 promotes tumour vascularization and can enhance the growth of ovarian tumours (Cunha et al. 2010, Herrera et al., 2009). The objective of this work is to determine if these contradictory effects are mediated by a loss of BMPR2 in the tumour vasculature endothelium. Adult C57/Bl6 mice, bearing a pulmonary endothelial-specific deletion of the gene encoding BMPR-II (Bmpr2EC-/-) and wildtype littermate controls (Bmpr2EC+/+), were administered syngeneic EO771 breast cancer cells into the mammary fat pad. These cells express red fluorescent protein (RFP) and were assayed for in vitro BMP9 responsiveness through qPCR, western blotting and proliferation assays. After four weeks, the primary tumour was resected to encourage lung metastasis. Four weeks after resection, study endpoint was reached, lungs were collected, and lung tumour burden was quantified as a measure of whole lung fluorescence. 2-photon confocal microscopy was used to quantify tumour burden and vascular network density in the explanted lungs. In vitro, stimulation of EO771 cells with BMP9 (10ng/mL) resulted in an increase in SMAD1/5/9 phosphorylation. However, this signalling response did not translate to a functional proliferative response to BMP9 treatment, relative to unstimulated controls. In vivo, no significant differences were observed in the growth of primary mammary tumours between Bmpr2EC+/+ and Bmpr2EC-/- mice (p=0.9). Lung
metastasis burden was also not significantly different in mice lacking pulmonary endothelial ii
Bmpr2, when compared to wildtype controls (p=0.2). Our findings suggest that pulmonary endothelial Bmpr2 loss enhances the growth of lung tumour metastases, and that growth is independent of any direct effects of BMP9 on EO771 proliferation. Ongoing studies are examining the effects of recombinant BMP9 administration on metastasis growth in this model, with and without endothelial Bmpr2 deletion.

abstract: M.Sc.


title: "Struggling with Development: planning problems and strategies in Melanesia"

type:
Text
masters thesis

publisher: Regional Planning and Resource Development, University of Waterloo (School of Urban and Regional Planning)


title: "After the Despot: changing patterns of leadership and social control in Kilenge, West New Britain Province, Papua New Guinea"

type:
Text
doctoral dissertation

publisher: Department of Anthropology, McMaster University


identifier: Wu, Zhao Xin   (2013).    Un modèle computationnel d'intelligence culturelle ouvert et extensible (thèse de doctorat en Informatique cognitive, Université du Québec à Montréal, Canada). Direction : Bourdeau, Jacqueline et Nkambou, Roger.

type:
Thèses et mémoires
PeerReviewed

abstract: Avec le phénomène de la globalisation qui prend de l'ampleur, les différences culturelles, dans les communications interculturelles, amènent leur lot de problèmes inévitables. Geet Hofstede a exprimé de manière représentative ce phénomène : "Culture is more often a source of conflict than of synergy. Cultural differences are a nuisance at best and often a disaster." (Geert Hofstede, Emeritus Professor, Maastricht University.) Dans la revue de la littérature, jusqu'à ce jour, les recherches relatives à l'intelligence culturelle (IC) utilisent les méthodes traditionnelles pour mesurer l'IC et trouver des solutions aux problèmes relatifs à l'IC. Ces méthodes dépendent essentiellement de questionnaires évaluant des aspects distincts, de documents (Ng et Earley, 2006) et d'évaluations variées, guidées par les connaissances spécialisées et des qualités psychologiques d'experts de l'IC. Ces façons de faire réduisent le nombre de solutions possibles. À notre connaissance, aucune recherche au sujet de l'IC n'a été empiriquement informatisée jusqu'à maintenant. En conséquence, l'intégration de l'IC dans le domaine de l'intelligence artificielle (IA) reste absente. L'objectif principal de la recherche est donc de créer un modèle computationnel de l'IC et de l'implémenter dans un système expert. Ce système se nomme Système Expert Neuro-Flou d'Intelligence Culturelle (SENFIC). Il intègre l'expertise d'experts de l'IC en intégrant le fruit des études à propos des quatre dimensions de l'IC comme un tout intégré et s'influençant les unes des autres. Il devrait permettre éventuellement d'atteindre un meilleur niveau de performance que celui des experts de l'IC. Comme un système intelligent efficace, il fournit une recommandation globale au problème et une forme de système de règles permettant l'adaptabilité des individus et des organisations à un environnement interculturel. C'est dans ce contexte que le SENFIC a vu le jour. Nous combinons deux techniques intelligentes dans le cadre du système. La technique d'hybride neuro-floue intégrant la logique floue et le réseau de neurones artificiels, et la technique du système expert. La technique de logique floue est une bonne solution pour exprimer des problèmes originalement en langue imprécise et naturelle, comme ceux soulevés dans les recherches relatives à l'IC. La technique du réseau de neurones artificiels aide le système à atteindre un niveau d'autorégulation, d'auto-adaptation et d'autoapprentissage. Le système expert utilise des connaissances et des procédures d'inférence dans le but de résoudre des problèmes difficiles, requérant normalement une expertise humaine dans le domaine d'IC. Ainsi, le SENFIC exprime des connaissances sous une forme facilement comprise par les utilisateurs, et traite les demandes simples en langage naturel plutôt qu'en langage de programmation. En utilisant une nouvelle approche pour la technique de soft-computing en concevant la technique hybride comme le cœur du système, notre SENFIC devient alors capable de raisonner et d'apprendre dans un environnement culturel incertain et imprécis. Ce SENFIC est ouvert et extensible, autant au niveau interne qu'externe. Au niveau interne, le modèle computationnel de l'IC fournit une interface standard pouvant faciliter le développement secondaire et la mise en pratique du système. Au niveau externe, le SENFIC a la capacité de se présenter comme un agent d'extension permettant l'intégration à n'importe quel système intelligent existant, pour que ce système devienne culturellement intelligent. Le SENFIC est « conscient de l'intelligence culturelle ». Cela représente une percée amenant son lot de contributions dans les domaines de l'IC et de l'IA.


identifier: Savard, Isabelle   (2014).    Modélisation des connaissances pour un design pédagogique intégrant les variables culturelles (thèse de doctorat en Informatique cognitive, Télé-université, Canada). Direction : Bourdeau, Jacqueline et Paquette, Gilbert.

abstract: Cette recherche porte sur la prise en compte des variables culturelles dans le processus de design pédagogique. Nous y émettons l’hypothèse qu’une méthode de traitement des variables culturelles pouvant se superposer au processus de design pédagogique permettrait aux concepteurs de prendre en compte et de traiter les variables culturelles, avec pour effets : d’augmenter l’efficacité des scénarios, un scénario efficace permettant à l’apprenant de développer les compétences visées et de les appliquer dans sa pratique; d’assurer un apprentissage significatif à l’apprenant; de favoriser l’équité, « toute personne [ayant] droit à une éducation et une formation de qualité qui respectent pleinement son identité culturelle » (UNESCO, 2002); et d’augmenter la réutilisabilité des ressources. Nous croyons également qu’en systématisant le support apporté aux concepteurs à l’aide d’outils basés sur les connaissances culturelles, nous leur permettrions de prendre en compte et de traiter les variables culturelles, tout en devenant des médiateurs créatifs plutôt que de simples consommateurs ou intermédiaires. Nous avons donc développé un modèle de la culture qui permet de comparer différentes cultures et qui facilite l’adaptation interculturelle. Cette recherche identifie également des variables culturelles inhérentes aux pratiques de design pédagogique. Celles-ci sont représentées sous la forme d’une ontologie, à partir de laquelle a été développée la base de connaissances « Diversité culturelle », qui regroupe de l’information sur la culture de cinq régions francophones : le Québec, l’Île Maurice, la France, la Belgique et le Gabon. Cette recherche propose également une méthode de traitement des variables culturelles, utilisée dans le cadre d’un scénario d’adaptation culturelle mettant en scène différents agents logiciels guidant le concepteur pédagogique dans son processus d’adaptation.


identifier: Belcourt, Claude   (2014).    Recherche de la mutualité ayant prévalu durant les sept premières années de l'instauration de l'encadrement par les pairs à partir des rapports produits par les pairs anciens (mémoire de maîtrise en Formation à distance, Télé-université, Québec, Canada). Direction : Deschênes, André-Jacques.

abstract:
Ce mémoire de maîtrise relève la mutualité qui a pu se manifester dans les interactions entre les pairs nouveaux et les pairs anciens au fil des activités de support à l’apprentissage entre pairs, durant les années 2001 à 2009 à la Téluq.

Partant des rapports produits par les pairs anciens (étudiants ayant déjà 12 crédits de faits) à propos de leurs interactions avec les pairs nouveaux (étudiants nouvellement inscrits à qui on a proposé librement un pair ancien pour l’aider), des indices de mutualité ont été recherchés dans le texte de ceux-ci.

Pour ce faire, une recherche visant à définir la mutualité de manière étoffée et à en révéler les caractéristiques a permis, à partir de lectures effectuées dans de multiples domaines de l’activité humaine où elle se révèle habituellement, de poser une définition opératoire et de bâtir une grille d’analyse.

Cette étude est complétée par un chapitre initial posant le contexte actuel de l’abandon dans les études tertiaires ordinaires ou à distance, et relevant les principaux moyens de soutien mis en place afin de contrer ce phénomène. De plus, elle est parachevée par un dernier chapitre de discussion sur les principales implications liées aux résultats.


identifier: Hombourger-Barès, Sabrina   (2014).    La contribution du design de l'espace de vente à l'évolution du positionnement de l'enseigne : une analyse longitudinale (thèse de doctorat en sciences de gestion, Université de Bourgogne). Direction : Filser, Marc.

abstract: L'une des voies d innovation plébiscitées par les détaillants pour orchestrer l'évolution de leur proposition de valeur consiste à réviser le design des espaces de vente. Les contributions académiques sur l'expérience en magasin se sont concentrées sur les perceptions des consommateurs ainsi que sur le repérage de pratiques managériales significatives. En prenant pour objet la traduction du repositionnement d'une enseigne par le design expérientiel des espaces de vente, la thèse propose de suivre le processus au coeur même du marché et de mettre à jour les mécanismes qui le sous-tendent. La conduite d'une étude longitudinale de cas enchâssés dévoile une conception holistique, basée sur l'interaction souhaitée du chaland avec le magasin. L'analyse relate l'enchâssement des quatre phases du cycle de vie et permet de recenser pour chaque phase les événements et problématiques associés aux six dimensions du processus. La thèse établit le rôle prégnant de la vision entrepreneuriale du dirigeant, clé de voûte de l'innovation. La proposition de valeur se matérialise par trois composantes gigognes que sont l'intrigue, l'action et le décor. Pour chacune des cinq étapes du parcours-client, des éléments de décor sont implantés pour relayer ou renforcer l'action souhaitée. Ces éléments constituent des mécanismes ou dispositifs destinés à stimuler le système expérientiel du chaland. L'évaluation, qui porte sur la mesure du positionnement perçu et vécu, contribue à ajuster la proposition de valeur au regard de quatre niveaux de cohérence et de la flexibilité du design. Enfin, les logiques de coproduction entre les différentes parties-prenantes au projet de conception occasionnent une possible co-destruction de valeur, intentionnelle ou accidentelle.


identifier: Asselin, Chantal   (2008).    Vers une définition de la formation à distance interculturelle (mémoire de maîtrise en Formation à distance, Télé-université, Québec, Canada). Direction : Bleton, Paul et Umbriaco, Michel.

abstract:
Ce mémoire de maîtrise tend à montrer comment la communauté d’apprenants natifs et non-natifs arrive à construire et co-construire ses connaissances sur une plateforme pluriculturelle, virtuelle et francophone par la création d’une culture commune. Il apparaît qu’en dépit de diverses origines premières culturelles et linguistiques, la communauté d’apprenants natifs et non-natifs bâtit son réseau d’apprentissage par le biais d’interactions pédagogiques.
En l’occurrence, le contexte « techno-pédagogique » collaboratif favorise la mise en place de cette « culture commune ». De plus, les théories éducatives cognitives et constructivistes expliqueraient les apprentissages réalisés lors des rencontres entre les locuteurs natifs et non-natifs. L’apprentissage collaboratif semble s’inscrire comme solution d’apprentissage.
Il s’ensuit que la théorie éducative sociocognitive historico-culturelle de Vygotsky (1978), la Zone de Développement Proximal de Vygotsky (1978), la théorie du conflit cognitif, le concept de proximité cognitive et les compétences herméneutique, linguistique, péri et paralinguistique dans la langue communicationnelle du cours/programme apparaissent favoriser la gestion des malentendus et conflits et la réussite (succès scolaire, rétention cognitive, hausse de l’autonomie) des apprenants à distance natifs et non-natifs.
En effet, nous constaterons que les résultats des entrevues auprès d’apprenantes nonnatives et de personnes enseignantes semblent révéler que la situation pédagogique tient une importance dominante par rapport aux autres éléments de contexte communicationnel et interculturel. De plus, bien que la connaissance (orale et écrite) de la langue du cours/programme s’avère évidemment pertinente, il semble que le fait que celle-ci soit une langue première, seconde ou étrangère importe dans la seule mesure où les capacités herméneutiques, péri et paralinguistique de la langue du cours/programme aident l’apprenant non-natif à construire, coconstruire et intégrer ses nouvelles connaissances.
Enfin, la communication pédagogique contextuelle, cognitiviste, constructiviste et médiatisée aide les apprenants à distance à gérer les malentendus et réussir leur cours/programme dans leur propre contexte d’apprentissage.
MOTS-CLÉS: malentendus interculturels, formation à distance, théories cognitivistes-constructivistes, communication pédagogique médiatisée


identifier: Balaguer, Jonathan Gabriel   (2011).    La place occupée par la FAD chez les officiers recrutés depuis moins de dix ans (mémoire de maîtrise en Formation à distance, Télé-université, Québec, Canada). Direction : Umbriaco, Michel.

abstract:
En 2006, la Défense nationale du Canada publie dans son énoncé politique de défense une nouvelle politique dans laquelle il est clairement stipulé que les FC seront une organisation plus contemporaine, c’est-à-dire plus flexible et efficace, axées sur le savoir. Cet énoncé permet clairement de voir qu’il y a aura un besoin accru de formation et ce dans tous les domaines. D’ailleurs, sur le terrain on constate que des transformations s’opèrent déjà sur la manière de former des officiers, puisque plusieurs officiers des FC sont embauchés sans même avoir complété un BAC tout en exerçant leur métier. Cette étude vise à mieux comprendre la place qu’occupe la FAD dans la formation universitaire des officiers recrutés depuis moins de dix ans.
Pour répondre à cette question de recherche, on s’appuie principalement au cadre de référence élaboré à partir des travaux de Lebaron sur l’enquête quantitative et à Wiener & Lerbet, sur la notion des boucles de rétroaction développées en cybernétique. On devrait expliquer brièvement ce que l’un et l’autre apporte. Dans la quatrième partie, la compilation et l’analyse des données de l’enquête, 37 questionnaires sont analysés dans l’objectif de répondre à la question de recherche.
L’analyse des données nous permet d’observer chez la plupart des 37 officiers, que la FAD dans les études universitaires occupe une plus grande place chez les officiers étant inscrit dans le programme de formation d’officier en éducation permanente (PFO-EP) comparativement à ceux étant inscrit dans le programme de formation universitaire pour les militaires du rang (PFUMR). C’est le PFO-EP qui retient le plus notre attention, car il se caractérise par le fait que dans une proportion de 85% les officiers désirent obtenir leur BAC via la FAD comparativement à 9% pour ceux étant inscrit dans le PFUMR. Aussi, les officiers ayant moins de 5 ans de service accordent plus d’importance à la FAD que ceux ayant entre 5 et 10 ans de service.
Aussi, la fin de notre enquête se doit d’être regardée sous deux plans, soit le plan de l’intervention et le plan de la recherche. C’est-à-dire que sous le plan de l’intervention, en intervenant plus de bonheur dans le plan décisionnel de l’officier dans le choix de son établissement d’étude ceci aurait pour effet de faire des économies soit en temps et argent et ce, à toutes les paliers. Et sous le plan de la recherche, les officiers interrogés n’ont pas encore terminé leur BAC, il y a encore beaucoup de nouvelles pistes à explorer, comme les fins de parcours des officiers à savoir s’il sont toujours dans le même programme, est-ce qu’ils ont abandonné, le pourquoi de ces choix, qu’est-ce qui a changé le parcours de l’officier? À la décision de quels nouveaux faits le parcours a changé? Donc il y aurait place à l’ouverture à des travaux ultérieurs.


identifier: Bilodeau, Sylvie   (2011).    Le développement professionnel autogéré du designer pédagogique en formation à distance (mémoire de maîtrise en Formation à distance, Télé-université, Québec, Canada). Direction : Page-Lamarche, Violaine.

abstract:
Dans le monde de l’éducation, il n’aura fallu que quelques années pour que naissent, s’imposent et se raffinent toute une panoplie de professions et d’outils associés à la formation à distance (FAD), grâce notamment, à l’essor constant des technologies de l’information et de la communication. Parmi eux, notons la profession de designer pédagogique et les diverses méthodes de design pédagogique. Le design pédagogique s’avère effectivement un outil indispensable aux mains de cet acteur clé en FAD qu’est le designer afin de l’assister dans sa pratique professionnelle. En plus de maîtriser cet outil de travail, le designer pédagogique doit également veiller à son développement professionnel par l’application de diverses méthodes et stratégies pour assurer la mise à jour de ses compétences et habiletés variées, car son contexte de travail est en perpétuel changement. Dans quelle mesure la pratique réflexive fait-elle partie des stratégies de développement professionnel du designer pédagogique? C’est principalement à cette question que cette recherche désire apporter une réponse.
MOTS-CLÉS
Formation à distance – design pédagogique – designer pédagogique – développement professionnel – compétence – compétence professionnelle – autoformation – pratique réflexive – réflexivité