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Type d'Item : Item , Webs, Symmetrizers, and the Oriented Skein Category(Université d'Ottawa / University of Ottawa, 2026-09-17) Samchuck-Schnarch, Saima; Savage, AlistairWe define and study the two-colour 𝖌𝖑-web categories Web↑(𝖌𝖑) and Web↑↓(𝖌𝖑), which generalize the 𝖌𝖑-web categories that have previously appeared in the literature. After establishing some basic properties of these categories, we show that Web↑↓(𝖌𝖑) is isomorphic to a partial idempotent completion of the oriented skein category 𝒪𝒮. This completion is obtained from 𝒪𝒮 by adjoining objects corresponding to the quantum symmetrizer and antisymmetrizer morphisms. We use this isomorphism to generalize results about web categories from the literature. In particular, we study the web incarnation functors from Web↑↓(gl) to the category of type 1 weight modules for the quantum enveloping superalgebra 𝑈_q(𝖌𝖑_m|n). Our approach allows us to translate fullness and kernel results for 𝒪𝒮-incarnation functors into corresponding theorems for web incarnation functors, extending existing results to new cases where the base ring is not a field.Type d'Item : Item , Cash Got Your Tongue? CEO Language-Uncertainty Around Undisclosed Cash Acquisitions(Université d'Ottawa / University of Ottawa, 2026-09-17) Soleimanipour, Sina; Akyol, Ali C.; Rajaiya, HarshitFirms host quarterly earnings calls and field analysts' unscripted questions, and the language a CEO uses in answering is increasingly read as a window into what managers know but have not yet disclosed. Yet when a firm is privately committed to an acquisition it has not announced, the executive holds the routine call unable to confirm or deny the one development that matters. Whether the spoken record tracks that withholding has not been characterized. We study the earnings-call transcripts and acquisition records of United States public firms from 2002 to 2018, covering 88,205 calls from 1,884 firms. From this language we construct a residual measure of CEO question-and-answer uncertainty - the part that remains once each executive's persistent speaking style is removed - and we track it around firms' cash acquisitions, with stock acquisitions as a comparison. We find that this residual uncertainty is elevated in the quarter before a cash acquisition, relative to the firm's own other quarters, with no comparable rise before stock acquisitions. Moreover, it becomes indistinguishable from zero in the first observed announced-but-not-closed call window, even before completion, while the cash that funds the purchase stays on the balance sheet until the deal closes. Furthermore, the elevation concentrates in cash acquisitions rather than stock acquisitions, a difference that survives a formal pooled test. This pattern is not accounted for by the analyst cash-scrutiny we can measure; we read it as call language that tracks the deal's passage from private to public, a within-firm correlational regularity rather than a tested mechanism. Finally, the residual is also unrelated to the firm's post-call bid-ask spread, a standard gauge of information asymmetry, while the scripted presentation is, contemporaneously and on one-tailed within-firm tests, positively associated with it, consistent with the two parts of the call relating to the outside information environment in different ways. Overall, a constrained executive's unscripted answers appear to carry a readable, anticipatory trace of an acquisition the firm has not yet disclosed.Type d'Item : Item , Surface-Engineered LLZO-PVDF Solid-State Electrolyte for Enhanced Solid-State Lithium Battery Performance(Université d'Ottawa / University of Ottawa, 2026-09-17) Mohammadiafzal, Parsa; Bruce, David R.The transition from laboratory-scale fabrication to industrial manufacturing remains a major challenge for the commercialization of composite solid electrolytes (CSEs) in all-solid-state batteries. PEO is limited by its low voltage stability, which motivates the use of PVDF-based electrolytes; however, PVDF systems also suffer from dehydrofluorination, particularly in the presence of LLZO, so we shifted to PVDF-HFP. Although the electrochemical and mechanical properties of PVDF-HFP/LLZO systems have been widely studied, scalable and continuous production methods compatible with industrial requirements are still limited. Conventional batch casting and static drying approaches suffer from low throughput, limited reproducibility, and poor process control for large-area films. In addition, the use of volatile organic solvents such as acetone raises concerns regarding safety, environmental impact, and large-scale applicability. Processing of PVDF-HFP typically relies on N-methyl-2-pyrrolidone (NMP) as a coating solvent, which raises environmental and health concerns due to its toxicological profile. These limitations have driven the search for safer and more sustainable alternatives, such as γ-valerolactone (GVL), for solid electrolyte fabrication. To address these limitations, this work first investigates γ-valerolactone (GVL) as a greener and less toxic solvent alternative for the preparation of composite electrolyte slurries. The results demonstrate that GVL-based systems can achieve comparable dispersion quality and suitable rheological properties for coating processes, while offering advantages in terms of reduced toxicity and improved sustainability. These findings highlight the potential of GVL as a viable solvent for environmentally responsible large-scale electrolyte production. Building on this, a roll-to-roll (R2R) continuous coating and drying platform was developed by modifying a commercial 3D printer into a multifunctional manufacturing system for solid electrolyte films. The system integrates either Mayer rod or slot-die coating techniques to enable precise thickness control and uniform deposition of PVDF-HFP/LLZO composite slurries onto flexible substrates. A downstream heated calendaring mill simultaneously applies pressure and thermal energy, promoting solvent removal, reducing porosity, and improving interfacial contact between polymer and ceramic phases. The platform allows systematic control over key processing parameters, including coating speed, drying temperature, and deposition method, enabling process optimization for scale-up. Continuous calendaring-assisted drying enhances film cohesion and mechanical integrity while maintaining compatibility with high ceramic loadings required for improved ionic conductivity. Stable and repeatable operation was successfully demonstrated at the pilot laboratory scale, confirming the feasibility of extended continuous production. In a nutshell, this study presents a practical and adaptable pathway for scaling up the production of PVDF-HFP/LLZO composite solid electrolytes. By integrating sustainable solvent selection with continuous manufacturing techniques, it establishes a foundation for producing uniform, mechanically robust electrolyte films suitable for next-generation solid-state battery applications. Here, we evaluate γ-valerolactone (GVL), a promising green-solvent based on its closeness to NMP in the Hansen Solubility Space. Through this study, we highlight that GVL is a promising candidate currently available that merits further investigation.Type d'Item : Item , DQN-Guided Rule-Class Selection for Search-Based Query Rewriting(Université d'Ottawa / University of Ottawa, 2026-09-16) Liu, Shengchen; Kantere, VerenaQuery rewrite transforms a SQL query into a semantically equivalent form expected to execute more efficiently. Search-based rewriters such as LearnedRewrite organize alternative rewrite orders as a policy tree and explore it with Monte Carlo Tree Search. In the publicly released LearnedRewrite implementation, expansion enumerates every applicable rule class at each search node, and each candidate triggers a rewrite execution and a PostgreSQL EXPLAIN call, making expansion a measurable contributor to rewrite latency. This thesis formulates expansion-time rule-class selection as a state-dependent decision problem and proposes DQRS (DQN-Guided Rule-Class Selection), which ranks the legal rule classes at each state with a Deep Q-Network and forwards only the top k to the unchanged rewriter routine. On an in-domain workload derived from the TPC-H benchmark at k = 1, average rewrite latency falls from 15.3 ms to 4.0 ms and average policy-tree size from 9.9 to 2.4 nodes, reductions of about 74% and 76%. Average cost reduction is preserved while the median falls from 156 to 103, so the method exposes an explicit operating point on the efficiency–quality trade-off rather than dominating the baseline. Under an identical legal-action mask and at the same node count, learned ranking attains a median cost reduction of 103 against 13 for random selection. Transferred without retraining to a workload derived from the TPC-DS benchmark at k = 4, DQRS reduces latency by about 24% and node count by about 30% at unchanged cost reduction, but in this saturated regime it is not distinguishable from random selection. The baseline throughout is the released implementation, which omits the learned cost estimator of the original paper, and all quality figures are optimizer-side estimates rather than measured execution time. Extending the evaluation from optimizer estimates to end-to-end execution time is the primary direction for future work.Type d'Item : Item , Comparative Analysis of Computational Methods for Optimal Transport(Université d'Ottawa / University of Ottawa, 2026-09-16) Zhytkevych, Ivan; Zarepour, MahmoudThis thesis presents a comparative and experimental study of computational methods for discrete optimal transport under the squared-Euclidean cost. We benchmark the exact simplex method, the Sinkhorn algorithm, first-order and quasi-Newton dual ascent, a chi-square-regularized primal-dual hybrid gradient (PDHG) method, and the Back-and-Forth method, across dimensions d in {1, 2, 3}, a range of grid resolutions and regularization levels, and a family of distributions varying in modality, tail thickness, skewness, and anisotropy. Solvers are assessed against three criteria - stability, runtime, and accuracy - and the conclusions are validated on a colour-transfer application. There we find that in RGB colour space the exact solver is not always preferable to a smoother, slightly biased map, which scores better on the structure-preservation metrics of SSIM, gradient correlation, and Laplacian sharpness. Beyond the comparison, we introduce a new method for the outer-regularized 2-Wasserstein barycenter based on Sobolev gradient ascent on the dual functionals combined with the Back-and-Forth c-transform, the simplest case of a broader Back-and-Forth Flow framework.