Recherche uO, le dépôt numérique de l'Université d'Ottawa, réunit le matériel de recherche et d'enseignement créé par notre communauté universitaire et nos partenaires. Le savoir de l'Université est ainsi disponible à long terme et en accès libre, ce qui lui procure de la visibilité et facilite sa diffusion.
Communautés dans DSpace
Sélectionner une communauté pour parcourir les collections sous-jacentes.
Nouveaux dépôts
Type d'Item : Item , Strategies for Coagulation Pretreatment of Low-Pressure Membranes(Université d'Ottawa | University of Ottawa, 2026-10-16) Ladouceur, Joseph D.; Lan, Christopher; Narbaitz, Roberto M.To mitigate natural organic matter (NOM)-induced fouling of low-pressure membranes (LPMs) in drinking water applications, coagulation pretreatment is widely applied. However, multiple process configurations exist and simulating full-scale performance at bench-scale remains a significant challenge. Accordingly, the main objectives of this dissertation were to compare the performance of alternative coagulation pretreatment strategies and to evaluate coagulation/flocculation mixing configurations for bench-scale LPM filtration studies. This research work was structured into four phases: (i) comparison of alternative coagulation pretreatment strategies across seasons and membrane types to identify optimal approaches; (ii) systematic investigation of the impact of helically coiled tube flocculator (HCTF) geometry on floc properties; (iii) evaluation of the influence of mixer configuration on bench-scale inline coagulation (C-IN) performance; and (iv) assessment of phased inline coagulation (C-IN-P), where coagulant is added for only a portion of the filtration cycle, as a more sustainable and cost-effective alternative to continuous C-IN. Conventional coagulation-flocculation-sedimentation (CF-SED) has proven effective for LPM pretreatment, although, coagulation-flocculation-dissolved air flotation (CF-DAF) represents a promising high-rate alternative. C-IN, which omits particle separation prior to membrane filtration, has gained popularity due to its reduced footprint and operational simplicity. For two different membrane types, CF-DAF and CF-SED performed equally well, despite improved NOM removal by CF-DAF. In contrast, the performance of C-IN was membrane dependent as it yielded the lowest fouling rate amongst alternatives for an inside-out polyethersulfone (PES) membrane, but the highest fouling rate for an outside-in polyvinylidene fluoride (PVDF) membrane. This finding highlighted the importance of membrane material/configuration for the selection of optimal LPM pretreatment, even when using the same source water. Seasonal differences in C-IN performance appeared to be caused by changes in the organic matrix affecting the coagulated zeta potential (ZP), suggesting that real-time ZP monitoring may serve as a useful optimization tool for C-IN-LPM hybrid systems. HCTFs represent a promising approach for improving continuous flow C-IN at bench-scale due to their strong secondary flow, which promotes effective mixing even for firmly laminar conditions. A replicated full-factorial design was used to evaluate the impact of the coil pitch, coil diameter, and pipe length on the properties of flocs. HCTF geometry was found to exert statistically significant impact on floc size and concentration, while floc structure (i.e., fractal dimension) remained relatively constant across all studied geometries. The system flowrate (i.e., Reynolds number), however, exhibited the greatest impact on HCTF performance, likely the result of a trade-off between the hydrodynamic condition and the hydraulic residence time. Compared to a batch-reactor, the tested HCTF configurations produced smaller sized flocs in greater concentrations, while relative to a commercial inline static mixer (ISM), HCTFs yielded larger sized flocs in lower concentrations. Bench-scale continuous-flow C-IN has proven difficult due to the low-flowrates involved. Accordingly, previous studies have used a wide variety of mixing configurations. The third phase of this study sought to elucidate the impact of mixer type/configuration on bench-scale C-IN performance by comparing three different continuous-flow flocculator types, namely, incidental flocculation in a straight pipe, an ISM, and two HCTFs, with and without the inclusion of rapid mixing. The performance of these continuous-flow approaches was additionally compared with a batch reactor, which have been extensively used in past studies due to their experimental simplicity. C-IN using a batch-reactor (with an extended contact time) yielded the lowest level of membrane fouling. Compared to rapid mixing or flocculation alone, combined rapid mixing and flocculation yielded reduced magnitude LPM fouling. Amongst alternative continuous-flow flocculator types, HCTFs had the lowest fouling rate, further supporting their suitability for bench-scale C-IN studies. These results indicate that LPM fouling is highly dependent on mixer type/configuration; direct comparison across studies using different C-IN approaches (including batch systems) may not be appropriate. The final phase evaluated the performance of C-IN-P using three synthetic waters with varying hydrophobicity. Intermittent addition over 75% of the filtration cycle achieved comparable fouling mitigation and NOM removal to continuous dosing, with only marginal performance losses when the length of coagulant addition was further reduced to 50% of the cycle. The optimal membrane coating index (C-IDX), an operational control tool for C-IN-P defined as the mass of coagulant per unit membrane area, was higher than values reported in the literature, even for the same membrane type and low hydrophobicity water types. This suggests that the optimal C-IDX is uniquely defined for each membrane-water combination. For a given C-IDX value, optimal performance was achieved when the jar-test optimal dose was used rather than different dosing rates applied for extended or reduced durations. Collectively, this work provides a comprehensive evaluation of alternative coagulation pretreatment strategies for LPMs and offers practical insights into the design, optimization, and bench-scale testing of these processes. The findings highlight the importance of membrane-specific optimization as well as the impact of mixer type/configuration on the outcome of bench-scale LPM studies.Type d'Item : Item , The New Tipping Point: A Critical Discourse Analysis of Anti-Trans Rhetoric in Canada, 2000-2023(Université d'Ottawa / University of Ottawa, 2026-10-16) Tacit, Sam; Saurette, PaulSince 2019, there has been a sharp increase of anti-trans rhetoric in Canadian politics and news. These discourses have culminated in provincial laws that limit trans children's and youths' rights, heightened skepticism toward gender affirmative care, and led to an increase in trans-hostile discourses circulating widely. Moreover, there are few academic inquiries into this phenomenon focusing on Canada at the time of this dissertation's publication. This dissertation tracked the contents and scope of anti-trans arguments in Canada to address this gap. A feminist critical discourse analysis and a mixed methods approach were applied. 500 cases collected from the period between January 1st, 2000, to December 31st, 2023, were selected from various Canadian sources. These cases were quantitatively coded using QDA Miner and qualitatively analyzed to track trends by overall data, time period, and type of actor. Some salient findings from this dissertation were: anti-trans actors in Canada have colonized liberal/progressive language, re-framing anti-trans speech as a political movement. Respectability politics portrayed trans people as 'extremists' who are destabilizing Canadian society. Legislative and rights-based arguments proliferated; most notably, the tension between parental rights and children's/student's rights were highlighted. During the period studied, anti-trans actors pivoted toward a child-centric focus, such as portraying children as being 'too young' to be 'exposed' to transness. Anti-trans actors portrayed transness as dangerous to cisgender men and women (i.e., by threatening gender roles) and to children (through 'trans predator' discourses that hypersexualized transness). Medical discourses portrayed gender affirmative care as unnecessary, often relying on claims that children were being 'rushed' into transitioning medically. Lastly, a common theme was the reification of the sex/gender binary. Anti-trans actors relied upon scientific, medical, political, sociocultural, and/or religious discussions to support their claims of a stable sex/gender binary. This dissertation has generated a wealth of data that captures anti-trans discourses in Canada. By understanding 'what' anti-trans actors are saying, one can develop theoretical and practical tool kits to slow, halt, and/or reverse the normalization of anti-trans discourse in Canadian politics and media.Type d'Item : Item , Umple User Manual V1.38(2026-10-15) CRuiSE Research Group; Lethbridge, TimothyUmple is a tool for creating models of software and generating code in Java, Python, PHP, C++ and other languages. Umple’s language is textual, but many kinds of diagrams and other outputs can be generated and used to help edit the text; these including state machines, state tables, class diagrams, feature diagrams, entity-relationship diagrams, message sequence tables, and instance diagrams. Umple allows embedding of several requirements formats such as user stories and use cases; Umple helps users understand the relationships (traceability) from the requirements to models and code, and vice-versa. Umple can be used online, as a command-line tool or in many integrated development tools (IDEs) such as VSCode, Zed, Cursor or BBEdit. These tools use Umple's Language Server Protocol (LSP) capabilities to help people edit their text. Developers can make extensive use of the modeling notations (data models, state models), but also embed code in target languages such as Java or Python to complete their system. This enables direct generation of systems from the Umple textual source. Umple's online tools enable users to use artificial intelligence (AI) to build systems reliably: Users pick a set of requirements in Umple and ask any AI to build Umple models, that can be deterministically transformed into code. This document is the pdf version of the Umple user manual as of version 1.38.0 (October 2025) and supersedes the 2021 version for version 1.30.2. Umple has been extensively improved since then, with numerous new capabilities. This version of the manual has over 890 pages and embeds over 550 examples. Most people will use the online html version of the manual, available at https://manual.umple.org, however some people prefer a printable or citable document. This document has the same content as the online version, and links will take readers to the online manual. All examples in the manual have links that open the example code in classic UmpleOnline at https://try.umple.org or a newer experience at https://newumpleonline.umple.org. Umple is an open-source project, developed by over 100 students at the University of Ottawa and elsewhere since 2007. The Umple compiler is written in itself. Umple is hosted on Github, at http://umple.org/code. Umple is targeted at open-source developers, so they can use it in their textual toolchain and develop code faster. It is also targeted at educators who want to teach modeling, as well as to enable students to create large, reliable, and complete executable systems from models, something that is more complex when using other modeling tools. Umple is also a research platform for studying software modeling, programming language technology, agile software development, AI in software engineering, and user experience. There are numerous scientific papers published about Umple. The definitive paper to cite is by Lethbridge, TC., Forward, A., Badreddin, O., Brestovansky, D., Garzon, M., Aljamaan, H., Eid, S., Husseini Orabi, A., Husseini Orabi, M.,Abdelzad, V., Adesina, O., Alghamdi, A., Algablan, A., Zakariapour, A. (2021) Umple: Model-Driven Development for Open Source and Education, Science of Computer Programming, Elsevier, https://doi.org/10.1016/j.scico.2021.102665 . That paper cites other relevant papers. A larger set of publications can be found at https://github.com/umple/umple/wiki/Publications . Umple is supported by NSERC and is hosted by the Digital Research Alliance of Canada.Type d'Item : Item , The Effects of Oral Contraceptive Use on Objective and Subjective Episodic Memory(Université d'Ottawa | University of Ottawa, 2026-10-15) Jensen, Adelaide; Davidson, Patrick S. R.Introduced more than 60 years ago, oral contraceptives (OC) are one of the most common forms of contraceptives used by reproductive-aged women today. Despite their widespread use, very little is known about the ways in which the hormones contained in OCs (i.e., synthetic versions of estradiol and progesterone) affect cognition, with much of the literature having been criticized for its predominance of cross-sectional designs, inconsistent consideration of OC-related factors (e.g., pill formulation, reproductive history/previous hormonal contraceptive use, group heterogeneity, etc.), and variable characterization and measurement of cognitive domains. Some studies have suggested that OC use may slightly enhance verbal episodic memory (i.e., our long-term, explicit recollection of personal events), although findings are mixed. It also remains unclear whether OC use alters subjective perceptions of one’s memory. Across three studies, this dissertation addresses the extent to which OC use might influence objective and subjective memory. I begin by describing the development and validation of the neuropsychological methods used in the second half of this thesis. Next, I cross-sectionally examine differences in subjective and objective memory between OC users and non-users. Finally, this thesis culminates with a quasi-experimental, repeated-measures investigation of objective and subjective memory changes in newly initiated OC users. We first tested the reliability of the Multifactorial Memory Questionnaire (MMQ)—a widely-used measure of subjective memory—for use with healthy young adults. Confirmatory factor analysis (CFA) with age invariance testing conducted with n = 408 young and n = 327 older adults suggested that although the MMQ is more reliable in older adults, it is also adequate for use in younger populations. Next, we piloted the remotely-administered, web-based implementation of a well-established episodic memory battery in n = 50 young adults and checked the feasibility of two parallel battery versions for repeated online testing. Additionally, using (young female participant only) data from a previous study employing a similar web-based battery, CFA was used to verify relationships between individual memory tasks in the battery and replicate its factor structure. The final study employed the measures verified above to systematically investigate the role of OC use in objective and subjective memory while addressing common methodological limitations in the literature. Cross-sectional analyses revealed slightly higher objective memory and memory satisfaction among OC users (n = 60) compared to non-users (n = 75); these results were also dependent on parallel task version and participants’ first language. Repeated measures analyses assessing group-by-time interactions, however, indicated no significant changes in objective or subjective memory in newly initiated OC users (n = 37) following three months/cycles of use, compared to long-time OC users (n = 43) and non-users (n = 45). Findings from the present dissertation shed light on the existing mixed evidence on the involvement of OCs in cognitive functioning and suggest that influences on memory may emerge following more prolonged exposure to OC hormones. Notably, this thesis also provides preliminary support for a possible role of contraceptives in subjective memory, particularly satisfaction with everyday memory functioning. Potential implications of our findings for the growing field of contraceptives and cognition research, including methodological considerations, underlying mechanisms of OC influences on cognition, and future research directions are discussed.Type d'Item : Item , Politicians, Elections, and Satisfaction with Democracy(Université d'Ottawa | University of Ottawa, 2026-10-15) Gaspard, Valere; Ferland, Benjamin; Turgeon, LucThe study of democracy is a vast field of political science. More recently, there is a renewed interest in understanding what might cause stable democracies to backslide or to resist decline. This critical moment in time, in which liberal democracies are now one of the least common regime types in the world, serves as a backdrop for the focus of this thesis: politicians’ assessments of electoral processes and the way democracy works. Politicians are particularly important for democratic stability. They can be central in the process of democratic resistance or decline because of their influence over the views of citizens, or if elected, their decision-making power within political institutions. Because of this, it is both timely and imperative for researchers to (re-)examine processes and institutions in democratic countries, like electoral processes, and what politicians think of them. Given the prominent role politicians have in democratic systems, this thesis presupposes that we can better understand the way democracy works by studying politicians directly, by considering what they think of the working of democracy, as well as examining how they engage with and think about electoral processes. However, while there is extensive research on citizens’ democratic satisfaction, there is less consideration of politicians’ attitudes and feelings about how democracy is working in their country. As such, this article-based thesis poses the following broad research question with respect to politicians: what are the determinants of politicians’ democratic satisfaction and their perceptions of the electoral process? Since elections are core to the democratic process, this thesis considers different aspects of the electoral process and how they might impact politicians’ democratic satisfaction as a starting point. In doing so, the three articles in this dissertation establish several theoretical and empirical contributions to the broader study of democracy, as well as the narrower fields of satisfaction with democracy (SWD), electoral processes, electoral management bodies (EMB), and politicians’ behaviours. Some of these contributions include its consideration of whether election-related determinants influence politicians’ SWD, deepening our understanding of how politicians’ perceptions of electoral processes and EMB design preferences are influenced by other election-related determinants, and the first study to use a conjoint experiment to assess EMB preferences. The findings in the three articles indicate that politicians generally want democracy and elections to function in accordance with classic democratic ideals.