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All in Good Conscience? Credit Relations and Power in Fifteenth Century England
Get PDFThis thesis examines the social and cultural dimensions of credit provision in fifteenth century England. During this period, individuals had to rely on members of their own social networks to access credit since no centralized financial institutions were available to borrow money from. Through an examination of various types of judicial records, including consistory court depositions, chancery bills of complaint, and court of common pleas case summaries, this thesis charts the availability of credit throughout the century and examines the different methods contemporaries used to help circulate value. Evidence form these sources reveals that the availability of credit waxed and waned throughout the century, being more easily accessible during its first few decades before becoming scarcer during the 1450s. Towards the end of the century, credit levels began a slow recovery. The extant records further demonstrate that throughout this period debts were not only reimbursed in coin. They could also be repaid in kind, through pledges of goods, or the enfeoffment of land. Moreover, this research reveals that bonds, although not fully negotiable, were routinely assigned to third parties, and thus helped to alleviate some of the financial difficulties caused by coin scarcity throughout the century.
This thesis also demonstrates how certain social groups dominated credit exchanges. Built on cultural norms such as trust and reputation, high-value credit transactions were dominated by merchants, men, and Londoners. This situation had important social and financial implications because loans, despite usury prohibitions, were interest-bearing and were thus treated by contemporaries as a type of investment. As a result, they became an important mechanism through which capital could be accumulated and financial resources centralized. These flows of capital thus contributed to the emergence of a national economy dominated by London merchants. Finally, credit relations were also shaped by and constitutive of power relations. Although power could be wielded by both debtors and creditors, English law afforded creditors a structural advantage in these exchanges since insolvent debtors could be imprisoned. This gave lenders the opportunity to make use of social capital to extract further concessions from borrowers
Investigation of Thermal Comfort in Multi-Occupant Office Spaces
Get PDFCanadians spend 80 to 90% of their time indoors and previous studies show that the vast majority are typically unsatisfied with their thermal comfort, especially in their workplaces. Building occupancy patterns have also dramatically changed in the past two years after the COVID-19 pandemic, given the unprecedented increase in telecommuting and the shift towards alternative office arrangements such as hot-desking, which are gaining widespread popularity. These changes pose new challenges to building operators, particularly due to larger variability in occupancy and occupant preferences compared to standard assumptions. Therefore, discovering personal comfort preference is key in optimizing room temperature for co-working spaces with variable occupancy. To this end, the goal of this research was to assess thermal comfort of occupants in a co-working space and investigate the differences in their comfort assessment under varying conditions using near real-time surveying methods. Other factors that might influence office comfort such as clothing and air velocity from ceiling diffusers were also investigated. The primary objective of this study is to leverage novel technologies such as wearables to identify thermal comfort levels in multi-occupant spaces in a continuous near real-time approach. The secondary objective is to find the statistical differences between surveyed occupants’ thermal comfort perception with respect to personal factors such as clothing, metabolic rates, and perception of air movements.
This research was conducted in the recently established living lab at Concordia university which features modern co-working spaces. Temperature ranges that correspond to survey responses continuously collected using a smartwatch have been analyzed and compared to assess if there are any statistical differences between the survey respondents when they are changing their clothing levels. Results showed statistically significant differences between respondents with regard to their thermal preferences (p-value = 2.2 *10-6), which also varied based on their clothing levels and metabolic rates. Finally, recommendations for using the results of this research to develop a control strategy for selecting optimal thermostat setpoints in response to variable occupancy were provided. This work is significant as co-working spaces with variable occupancy are on the rise. Therefore, identifying individual thermal comfort preferences can be used to formulate algorithms to satisfy most people who occupy (or are expected to occupy) these spaces while minimizing energy waste during under occupied periods
What They Really Think: A Qualitative Analysis of Graduate-Level Science Students’ Views on Science Journalism
Get PDFThis thesis examines how graduate-level science students view science journalism, investigating how discussions in formal or informal pedagogical settings with professors and peers intersect with one’s likelihood to participate in science journalism activities. Through the use of semi-structured interviews, twelve graduate-level science students shared their thoughts on various topics related to science journalism. Grounded theory using thematic analysis resulted in the development of a framework for considering how this largely unstudied group of future scientists perceive science journalism: The Four T’s of Science Journalism. The research posits that graduate-level science students employ normalized behaviors fostered in science programs when consuming news, wherein they become critical analyzers of news stories, actively seeking discrepancies in the news stories they read. Regardless of the nature of conversations around science journalism in classroom or casual settings, and the news consumption habits of students, the research argues that the scientists of tomorrow are eager to learn about and participate in the creation of science journalism, pointing to the critical necessity to further assess how science journalism is woven into graduate-level science programs today and the urgency to which the disparate literatures of science communication and science journalism should be bridged in the pursuit of creating meaningful science journalism for public audiences
The influence of sex and pain catastrophizing on conditioned pain modulation in athletes
Get PDFContext: Recent findings suggests that athletes have enhance pain modulatory systems compared to non-athletes, despite being constantly subjected to painful stimuli through training and competition. Measurements such as conditioned pain modulation (CPM) is one test that we can use to compare modulatory pain processes. CPM has been shown to be different in non-athlete males and females, but to our knowledge, no study has examined the sex differences in CPM in athletes. In addition, psychological factors, including pain catastrophizing, may explain why athletes perceive and express pain differently. Objective: To compare the sex differences in pain ratings, pressure pain threshold (PPT), and cardiovascular variables in athletes during a CPM protocol; and to determine influence of pain catastrophizing and other psychological factors with pain and cardiovascular variables recorded during a CPM protocol. Design: Cross-sectional design. Setting: Laboratory. Participants: 120 athletes (60 females) from various sports participated in this study. Main Outcome Measures: We measured catastrophizing using the Pain Catastrophizing Scale and pain using an 11-point numeric pain rating scale. CPM was measured using pressure pain threshold (PPT), which was measured on the thenar eminence and tibialis anterior before and after a cold pressor test (CPT). Results: During the CPT, participants experienced increases in subjective pain ratings, but pain intensity did not differ between males and females. We observed increases in PPT measures following the CPT in males and females, but males displayed higher PPT measures than females at pre- and post-CPT. In addition, we did not identify a relationship between any psychological factors and subjective pain ratings during the CPT. Conclusions: Our results suggest that psychological factors do not influence pain perception during a CPT and that male athletes present greater PPT measures than female athletes
Immigrant Parents' Perspectives on Heritage Language Maintenance and Multilingual Digital Books
Get PDFABSTRACT
Immigrant Parents’ Perspectives on Heritage Language Maintenance and Multilingual Books
Onyemechi Fikani
Many immigrant parents in Canada seek to foster their children’s language and literacy development in a heritage language as well as the official languages of English and French. The purpose of this study is to describe immigrant parents’ (a) beliefs and practices related to passing on a heritage language to their children and (b) views on using websites providing digital stories in multiple languages as a resource to support the heritage language.
Through two semi-structured interviews, eight parents reflected on their heritage language and literacy practices, shared their beliefs about heritage language maintenance, and described their experience of sharing digital stories on the Storybooks Canada and Global Storybooks websites with their children. Analysis of the interview transcripts revealed that participants engaged in parent-child conversations, storybook reading, and storytelling to support their children’s language development in both the heritage language and one or both of Canada’s official languages. The parents also believed that multilingualism was pertinent to the future of their children and valued the role of extended family and community in passing on their home language, culture, and identity. To support their efforts to transfer heritage languages, parents reported they needed more resources, language schools, and access to books in their home languages. Additionally, parents believed that the storybook websites were helpful in the maintenance of heritage languages and most (6 of the 8 participants) showed interest in incorporating the websites into their language and literacy practices. The findings can inform schools, families, and immigration policymakers
New Insights on Catastrophic Forgetting in Neural Networks
Get PDFContinual learning, the ability of agents to learn from a changing distribution of data while respecting memory and compute constraints, is a challenging and important problem in machine learning. The central challenge of Continual Learning (CL) is to balance effective adaptation of new information while combating catastrophic forgetting, \textit{i.e.} stability-plasticity dilemma. This thesis is comprised of four major chapters that explore different aspects of continual learning and propose novel solutions to address some of its challenges.
First, we investigate the impact of experience replay (ER) on the change in representations of observed data that arises when previously unobserved classes appear in the incoming data stream. We show that applying ER causes the representations of newly added classes to overlap significantly with the previous classes, leading to highly disruptive parameter updates. To mitigate this issue, we propose a new method that shields the learned representations from drastic adaptation to accommodate new classes. Specifically, we use an asymmetric update rule that pushes new classes to adapt to the older ones, which is more effective, especially at task boundaries where much of the forgetting typically occurs. Empirical results on standard continual learning benchmarks show significant gains over strong baselines.
Then, we focus on the concept of representation forgetting, which refers to the change in a model's representation without losing knowledge about prior tasks. We observe that models trained without any explicit control for forgetting often experience small representation forgetting, which can sometimes be comparable to methods that explicitly control for forgetting, especially in longer task sequences. We propose a simple yet competitive approach to learning representations continually with standard supervised contrastive learning while constructing prototypes of class samples when queried on old samples. We show that this approach can lead to new insights on the effect of model capacity and loss function used in continual learning.
Finally, we address the challenge of balancing effective adaptation while combating catastrophic forgetting, i.e. stability-plasticity dilemma, without relying on prior task data. We propose a holistic approach to jointly learn the representation and class prototypes while maintaining the relevance of old class prototypes and their embedded similarities. We use a supervised contrastive loss to learn representations in an embedding space and evolve class prototypes continually in the same latent space, enabling learning and prediction at any point. To continually adapt the prototypes without keeping any prior task data, we propose a novel distillation loss that constrains class prototypes to maintain relative similarities as compared to new task data. Empirical results show that this method yields state-of-the-art performance in the task-incremental setting and provides strong performance in the class-incremental setting without using any stored data points.
Overall, in this thesis, we provide new insights and methods for effective adaptation in CL without catastrophic forgetting. The proposed methods achieve state-of-the-art performance on standard continual learning benchmarks and provide new insights into the role of model capacity, loss functions, and forgetting in CL
Fish biodiversity and morphological quality in small agricultural streams of Monteregie, Quebec
Get PDFStream channelization and modification is a widespread practice on agricultural land in Monteregie, Quebec, however, it is well known that channel simplification reduces the variability of instream habitat complexity and affects the biodiversity of these streams. Despite over 30,000 km of streams being subjected to channelization-type development in Quebec, very little is known about the extent of stream degradation and effects it may have on local geomorphology and ecology. The Morphological Quality Index (MQI) is a tool used to measure a stream’s hydrogeomorphological quality and has been shown to be a reliable predictor to help assess habitat quality in small headwater streams. The purpose of this research is to determine the health of fish communities in small streams in Monteregie and assess whether there is a significant relationship between biological communities and the MQI. Over 1,220 fish samples and 85 stream reaches with drainage areas less than 130 km2 were analysed in Monteregie. Results showed that small streams in Monteregie were higher in fish biodiversity than expected, with clear relationships between the fish metrics and proportion of land use in forested or agricultural categories. The MQI was also able to predict biological communities with up to an R2 = 0.50, which shows that the MQI could be used as a reliable tool to efficiently assess streams while providing insight on how stream modification affects overall biodiversity in agricultural watersheds
EFSM-based Test Suite Generation for MC/DC Compliant Systems: Tool Design
Get PDFAs Model-based Testing (MBT) approaches mature, they become a promising prospect for Safety-critical software systems testing. It is necessary to abide by RTCA DO-178C regarding requirement coverage, structural coverage, and traceability. The satisfaction of Modified Condition/Decision Coverage (MC/DC) is a must for avionics software certification. This thesis proposes a tool design for a test generation approach that satisfies the Modified Condition/Decision Coverage (MC/DC) and addresses path feasibility issues using constraints solving. The proposed methodology has several steps. It starts by transforming Low-Level Requirements (LLR), modelled as Extended Finite State Machines (EFSM), into a data-flow graph and a control-flow graph. Then, we highlight MC/DC information on both graphs, using graph labelling, before applying SMT-constraint solving to generate an executable test suite. Throughout, we keep records of the transformation between the models to prepare for requirements traceability as per RTCA DO-178C. The approach is based on the EFSM model, meaning that the assessment of MC/DC and other structural coverage criteria are on the model under the assumptions that the predicates are the same in the code and the model, and the model is valid
Using Translation Tools for L2-Learning in a Self-Regulated Environment
Get PDFThe goal of this dissertation is to investigate the use of Google Translate (GT), a free online translation software that includes translation, Text-to-Speech (TTS), and Automatic Speech Recognition (ASR) functionalities, for online self-regulated learning of Mandarin Chinese within an interactionist approach. It also explores how GT can be used for pedagogical purposes within a complex learning environment that combines computer-assisted language learning (CALL), online self-regulated learning (SRL), and informed by interactionist theories. This dissertation begins with a review of the literature around the importance of interaction in language learning, followed by how a fully online interactionist approach using GT as a language partner and interlocutor allows learners to practice language use whenever and wherever they please (Chapter 1). Next, the dissertation contains three manuscript-based chapters (Chapters 2, 3, and 4) and a concluding chapter (Chapter 5). Each manuscript explores one aspect of using GT for pedagogical purposes by addressing the following overarching research questions: 1) Can GT provide the necessary computer-assisted interaction including input, output, and feedback to promote second language (L2) learning (Manuscripts 1 and 2), and 2) Are learners willing and able to use GT in an online, self-regulated environment for the learning of Mandarin and its associated tones? (Manuscript 3).
The first manuscript investigates the use of GT’s TTS as a source of Mandarin Chinese input when compared with a native speaker in terms of Intelligibility (how much is understood), Comprehensibility (how challenging something is to be understood), and Naturalness (how much does a synthesized voice differ from a human speaker). The second manuscript further explores GT’s ability to interact with a human interlocutor by investigating how much Mandarin Chinese speech can GT recognize at various language levels (intermediate, advanced, and native) and whether it can provide transcriptions accurate enough to be used as feedback by the language learner. The third and final manuscript investigate the pedagogical feasibility of using GT and its built-in features (translation, TTS, ASR) in an online, self-regulated environment by exploring how a small group of participants acquire language features, develop self-regulated learning strategies, and perceive the GT-enhanced pedagogical environment as a venue for language learning.
This dissertation will contribute to the literature around using translation, TTS, and ASR software for language learning, as well as interaction theories, SRL, CALL, and the acquisition of Mandarin Chinese in general. This research innovates on existing online language learning research and interactionist approaches by positioning GT as an interlocutor despite its intrinsic limitations (it is after all, not a human). This dissertation will further help guide future research into how human beings can interact with computers for language learning and will only become more relevant as translation, TTS, and ASR software becomes more intelligent, capable, and life-like
Microstructural, mechanical, and tribological evaluation of thermally sprayed wear-resistant coatings for aerospace applications
Get PDFThermal sprayed tribological coatings have been used extensively in aerospace applications, primarily to overcome critical challenges such as abrasive wear, corrosion, erosion, oxidation and fatigue at high temperatures and pressures. Such coatings can also play a critical role in optimizing the efficiency of gas turbine engines, thereby reducing fuel consumption and CO2 emissions. High Velocity Oxy-Fuel (HVOF) thermal spraying with its higher gas jet velocity and lower flame temperature as compared to Air Plasma Spray (APS) is a promising deposition technique that can be used to deposit nickel- and copper- based tribological coatings. More specifically, dense coatings with lower oxide content and higher hardness have made this process a promising technique for producing wear resistant coatings capable of operating effectively in extreme environments.
The main objective of this research is to study the tribological properties of NiGraphite and Cu-Al systems deposited by HVOF and APS deposition processes in order to compare and determine the most suitable thermal spraying parameters. This work consists of two research studies, the first of which focuses on the tribological performance of HVOF-sprayed nickel graphite coatings with different compositions at room temperature and 450 °C. The second study evaluates the temperature response (room temperature, 300 °C and 450 °C) on the hardness and sliding wear behavior of Cu-10Al coatings deposited by HVOF and APS.
In both studies, the tribological tests were performed using a ball-on-flat tribometer and the wear profiles were extracted using a laser confocal microscope. Ex-situ characterization of the coatings was performed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), image analysis, and Vickers microhardness testing at room and elevated temperatures. The HVOF 75Ni-25Gr coating showed the lower wear rates compared to 85Ni-15Gr at 450°C, while the wear rates of both coatings were similar at room temperature. The APS Cu-10Al coating showed better wear resistance compared to the HVOF coating at all test temperature