cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Decision Frequency Adaptation in Reinforcement Learning Using Continuous Options with Open-Loop Policies
Creators: Karimi, Amirmohammad
Publisher: name: University of Alberta Library
Year: 2023

In classic reinforcement learning(RL) for continuous control, agents make decisions at discrete and fixed time intervals. The duration between decisions becomes a crucial hyperparameter. Setting it too short may increase the problem’s difficulty by requiring the agent to make numerous decisions to achieve its goal, while setting it too long can result in the agent losing control over the system. However, physical systems do not necessarily require a constant control frequency. For learning agents, it is often preferable to make decisions with a low frequency when possible and a high frequency when necessary. Previously, control frequency adaptation methods in temporal-abstraction RL have been proposed. However, like classic RL, these methods often do not consider physical time and treat task time steps discretely. This can make the learning experience sensitive to the underlying task interaction frequency. We propose a framework called Continuous-Time Continuous-Options (CTCO), where the agent chooses options as open-loop sub-policies of variable durations. These options are defined in continuous time and can interact with the system at any desired frequency providing smooth extended continuous actions. We demonstrate the effectiveness of CTCO by comparing its performance to classical RL and temporal-abstraction RL methods on simulated and real-world continuous control tasks with various action-cycle times. We show that our algorithm’s performance is not affected by the choice of task interaction frequency. Moreover, we show the benefit of having open-loop options over simple action repetition. Furthermore, we demonstrate the efficacy of CTCO in facilitating exploration in a real-world visual reaching task with sparse rewards for a 7 DOF robotic arm.
Large SU(3) breaking effects and CP violation in $B^+ $ decays into three charged SU(3) octet pseudoscalar mesons
Creators: name: Xu, Dong
name: Li, Guan-Nan
name: He, Xiao-Gang
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: TThe LHCb collaboration has recently reported evidence for non-zero CP asymmetries in $B^+$ decays into $π^+ K^+ K^-,\; π^+π^+π^-,\; K^+ K^+ K^- $ and $K^+π^+π^-$. The branching ratios for these decays have also been measured with different values ranging from $5\times 10^{-6}$ to $51\times 10^{-6}$. If flavor $SU(3)$ symmetry is a good symmetry for $B$ decays, in the case that the dominant amplitude is momentum independent it is expected that branching ratios $Br$ and CP violating rate differences $Δ_{CP} = Γ- \overlineΓ$ satisfy, $Br(π^+π^+π^-) = 2Br(π^+ K^+ K^-)$, $Br(K^+K^+K^-) = 2 Br(K^+π^+π^-)$, and $Δ_{CP}(π^+π^+π^-) = 2Δ_{CP}(π^+ K^+K^-) = - Δ_{CP}(K^+K^+K^-) = -2Δ_{CP}(K^+π^+π^-)$. The experimental data do not exhibit the expected pattern for the branching ratios. The rate differences for $B^+\to π^+π^+π^-$ and $B^+\to K^+ K^+ K^-$ satisfy the relation between $ΔS =0$ and $ΔS=1$ well, but the other two do not, with the CP asymmetries having different signs than expected. In this work we study how to including momentum dependent and also $SU(3)$ breaking effects on these decays to explain experimental data. We find that only including lowest order derivative terms, in the $SU(3)$ limit, the decay patterns cannot be explained. Large $SU(3)$ breaking effects are needed to explain the data.
description: Review Tex, 20 pages, no figure. Materials extensively extended to include momentum dependent decay amplitudes
The Interaction of Newly Forming Frazil Ice and Sediments
Creators: Hong, Xun
Publisher: name: University of Alberta Library
Year: 2023

In river freeze-up periods, small disc-shaped frazil ice forms during supercooling in turbulent river flow. Under continuous cooling, these particles collide and freeze to form frazil flocs and entrain suspended sediments. Sediment-laden flocs might rise to the surface and freeze into frazil pans, eventually becoming ice cover; or sinking to the bottom and forming anchor ice. Studies of the interaction between newly forming frazil ice and suspended sediments in northern rivers during the freeze-up period are limited. This study investigated how the suspended sediment concentration changes in the water column, which sediment sizes are more likely to get entrained in the frazil ice, and how organic content changes during the supercooling process. To study the sediment concentrations in natural frazil ice, samples were collected from the North Saskatchewan River during the freeze-up period of 2021. Laboratory experiments were done in a freshwater frazil tank in a cold room with three types of sediments (clay-silt, natural, and sand) under three initial concentrations. Samples, including the initial tank water, final tank water, interstitial water, and drained ice, were filtered to examine the sediment concentrations to study the sediment entrainment mechanism.

Results showed that when frazil ice formed in turbulent tank water, up to 75% of suspended sediments were removed from the water column, even though only 2~3% were entrained in the frazil ice. Based on observations, this is likely because sediment-laden frazil flocs can be shredded by propellers, releasing sediments close to the tank bottom. In addition, the sediment concentrations of the final tank water showed that coarser sediments were removed more efficiently than finer sediments, likely because finer sediments are easier to suspend. Sediments were trapped inside the porous ice lattice of frazil flocs as sediment-laden water flowed through the flocs, like a sieving process. Coarser sediments were more easily entrained in frazil flocs, and finer sediments were more easily flushed out with water, as proven by the ratio of sediment concentrations in the drained ice versus interstitial water 0.7 for clay-silt, 2 for natural, and 3.3 for sand. Sediment concentrations in the field drained ice, and interstitial water samples ranged from 76.7 to 1244 mg/L and 15.1 to 48.9 mg/L. The field's drained ice versus interstitial water ratios (1.8~51) are much bigger than in the lab. Because sediments used in the lab were well-sorted in a specific range, field frazil can entrain small rocks that significantly increase the sediment mass in ice samples. The organic content in river water samples (0.18~0.6) was much higher than tank water samples (0.09~0.13); however, the organic content in drained ice samples from the river (0.05~0.14) and tank (0.1~0.17) was similar to each other, suggesting consistent organic harvesting ability of ice.
First Evaluation of the CPU, GPGPU and MIC Architectures for Real Time Particle Tracking based on Hough Transform at the LHC
Creators: name: Halyo, V.
name: LeGresley, P.
name: Lujan, P.
name: Karpusenko, V.
name: Vladimirov, A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Recent innovations focused around {\em parallel} processing, either through systems containing multiple processors or processors containing multiple cores, hold great promise for enhancing the performance of the trigger at the LHC and extending its physics program. The flexibility of the CMS/ATLAS trigger system allows for easy integration of computational accelerators, such as NVIDIA's Tesla Graphics Processing Unit (GPU) or Intel's \xphi, in the High Level Trigger. These accelerators have the potential to provide faster or more energy efficient event selection, thus opening up possibilities for new complex triggers that were not previously feasible. At the same time, it is crucial to explore the performance limits achievable on the latest generation multicore CPUs with the use of the best software optimization methods. In this article, a new tracking algorithm based on the Hough transform will be evaluated for the first time on a multi-core Intel Xeon E5-2697v2 CPU, an NVIDIA Tesla K20c GPU, and an Intel \xphi\ 7120 coprocessor. Preliminary time performance will be presented.
description: 13 pages, 4 figures, Accepted to JINST
Copula-Based Survival Models for Dependent Competing Risks
Creators: Hossein Gharari Foomani, Ali
Publisher: name: University of Alberta Library
Year: 2023

A survival dataset describes a collection of instances, such as patients, and associates each instance with either the time until an event (such as death), or the censoring time (eg, when the instance is lost to follow-up), which is a lower bound on the time until the event. While there are several approaches to survival prediction, this thesis focuses on models that produce an individual survival curve (providing P(death ≥ t|x) for each t > 0) for each individual patient, x – here based on a “Deep Weibull” model. Most survival prediction methods assume that the event and censoring distributions are independent given the instance’s covariates. This assumption is challenging to verify since we only observe a single outcome (event xor censor time) for each instance. Moreover, models that assume this independence can be substantially biased when this independence does not hold. Moreover, the standard methods to evaluate survival models do not provide meaningful values here.

In this study, we present a way to relax the assumption of conditional independence, using a parametric model of survival that incorporates Archimedean copulas to address residual dependency that cannot be explained by the co-variates in the dataset. Additionally, we show how to extend this to a broader range of dependencies by using a convex combination of members from the Archimedean copula family, rather than relying on a specific member. Our empirical studies, conducted on synthetic and semi-synthetic data, demonstrated that our approach significantly improves the estimation of survival

distributions in terms of log-likelihood (which is a proper scoring for the survival analysis task) and L1 survival distance (which we proposed), compared to the standard approach that assumes conditional independence.
Development of New Late-Stage Labeling Methods with Labeled Carbon for Stabilized Carboxylic Acids and α-Amino Acids
Creators: Bsharat, Odey Falah
Publisher: name: University of Alberta Library
Year: 2023

Isotope labeling of small molecules is a crucial tool for drug discovery and understanding biochemical processes. Expanding the toolbox of a radiochemist with methods that allow late-stage labeling is therefore important. Of the methods that have been developed, the use of isotopically labeled CO2 ( = 14, 13, 11) precursor is among of the most useful platforms for installing isotopically-labeled carbon into the molecule. While this area has undergone a tremendous amount of development in recent years, the preparation of isotopically-labeled molecules with isotopically labeled C ( = 14, 13, 11) remains difficult and time consuming, with established methods involving label incorporation at an early stage of synthesis. This thesis describes the development of new methods to label stabilized carboxylic acids and α-amino acids with CO2 ( = 14, 13, 11). It describes reversible decarboxylation/carboxylation reactions by stabilized carboxylic acids and their derivatives that prepare isotopically-labeled carboxylic acids. Through careful pilot studies, reaction optimization, and mechanistic probes, the achiral aryl aldehyde catalyzed isotopic carboxylate exchange of native α-amino acids with CO2 ( = 14, 13, 11) was discovered. This reaction likely proceeds via the trapping of *CO2 by imine-carboxylate intermediates to generate iminomalonates that are prone to monodecarboxylation. Subsequent work revealed that a chiral aldehyde receptor can mediate the resolution/carboxylate exchange of native α-amino acids with *CO2.
Supplementary Information from Multistable bioinspired origami with reprogrammable self-folding
Creators: name: Rojas, Salvador
name: Riley, Katherine S.
name: Arrieta, Andres F.
Publisher: name: The Royal Society
Year: 2022
Subjects: subject: Biological Engineering
subject: 90301 Biomaterials
subject: FOS: Medical engineering
subject: 30402 Biomolecular Modelling and Design
subject: FOS: Chemical sciences

description: Full document to reproduce results and replicate experiments
Higgs Boson Production in Gluon Fusion through the Next-to-Next-to-Leading Power in Quark Mass
Creators: Modi, Sneh K
Publisher: name: University of Alberta Library
Year: 2023

The asymptotic behavior of the elementary particle scattering amplitudes at high-energy is a fundamental problem of quantum field theory.

In the leading order of the expansion in inverse powers of the characteristic energy scale, the problem has been solved decades ago in the classical works of Sudakov and others

\cite{Sudakov:1954sw,Frenkel:1976bj,Smilga:1979uj,Mueller:1979ih,Collins:1980ih,Sen:1981sd,Sterman:1986aj,Korchemsky:1988hd,Korchemsky:1988pn}.

Beyond this approximation, however, the problem becomes far more challenging and requires the development of principally new theoretical techniques.

Only recently the solution has been found for the leading mass-suppressed amplitudes revealing a number of amazing new effects in quantum field theory \cite{Penin2015,Penin2016,Liu2017,Liu:2017vkm,Liu2018}.

In this thesis, we make further advances in the analysis and consider for the first time a high-energy process at the next-to-next-to-leading power.

The main focus of the thesis is the analysis of the QCD effects in the light quark mediated Higgs boson production via gluon fusion.

We study the dominant ``double-logarithmic" radiative corrections enhanced by the second power of the logarithm of the light quark to Higgs boson mass ratio per each power of strong coupling constant $\alphas$.

The analytic result is obtained for the three-loop $\alphas^3$ contribution through the third power in the quark mass.

The all-order double-logarithmic asymptotic result is then obtained in two complementary approximations: (i) the large number of colors limit which is supposed to catch the qualitative behavior of real QCD, and (ii) in the Abelian limit which fully reveals the structure of the double-logarithmic result at the next-to-next-to-leading power.

The second problem considered in the thesis is the asymptotic behavior of the massive quark scattering amplitudes by an external color singlet field.

The all-order result at next-to-leading power in quark mass for which was first obtained in \cite{Liu:2017vkm,Liu_2018}.

We complete this previous analysis and obtain for the first time the fully analytic asymptotic result for the leading mass-suppressed term in the double-logarithmic approximation.
Cooperative Motion of Active Brownian Spheres in Three-Dimensional Dense Suspensions
Creators: name: Wysocki, Adam
name: Winkler, Roland G.
name: Gompper, Gerhard
Publisher: name: arXiv
Year: 2013
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Biological Physics (physics.bio-ph)
subject: Computational Physics (physics.comp-ph)
subject: Cell Behavior (q-bio.CB)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: The structural and dynamical properties of suspensions of self-propelled Brownian particles of spherical shape are investigated in three spatial dimensions. Our simulations reveal a phase separation into a dilute and a dense phase, above a certain density and strength of self-propulsion. The packing fraction of the dense phase approaches random close packing at high activity, yet the system remains fluid. Although no alignment mechanism exists in this model, we find long-lived cooperative motion of the particles in the dense regime. This behavior is probably due to an interface-induced sorting process. Spatial displacement correlation functions are nearly scale-free for systems with densities close to or above the glass transition density of passive systems.
description: 6 pages, 7 figures
Biochemical Approaches for Studying the Role of CD33 in Alzheimer’s Disease Susceptibility
Creators: Jung, Jaesoo
Publisher: name: University of Alberta Library
Year: 2023

Alzheimer’s disease (AD) is a common neurodegenerative dementia, and its pathological hallmarks include amyloid-β plaque and neurofibrillary tangle formation in the brain. Genome-wide association studies (GWAS) revealed that a rare single nucleotide polymorphism (SNP) in CD33 is associated with AD susceptibility. This SNP regulates alternative mRNA splicing to generate long (CD33M) and short (CD33m) protein isoforms. These two CD33 isoforms differ in the presence and absence of the V-set glycan-binding domain. Therefore, as higher expression of CD33M correlates with increased AD risk, there is a correlation between loss of glycan binding and AD susceptibility. As the glycan ligands for CD33M are not well understood, the major objective of this thesis is to develop biochemical tools to study the glycan ligands of CD33. To complement studies on CD33M, a second objective is to develop approaches for better understanding alternative mRNA splicing of CD33.
Additional file 1 of Fear of movement was associated with sedentary behaviour 12 months after lumbar fusion surgery in patients with low back pain and degenerative disc disorder
Creators: name: Jakobsson, Max
name: Hagströmer, Maria
name: Lotzke, Hanna
name: von Rosen, Philip
name: Lundberg, Mari
Publisher: name: figshare
Year: 2023
Subjects: subject: Medicine
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Physiology
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Science Policy

description: Supplementary Material 1
Exploring the conformational dynamics of alanine dipeptide in solution subjected to an external electric field: A nonequilibrium molecular dynamics simulation
Creators: name: Wang, Han
name: Schütte, Christof
name: Ciccotti, Giovanni
name: Site, Luigi Delle
Publisher: name: arXiv
Year: 2013
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: In this paper, we investigate the conformational dynamics of alanine dipeptide under an external electric field by nonequilibrium molecular dynamics simulation. We consider the case of a constant and of an oscillatory field. In this context we propose a procedure to implement the temperature control, which removes the irrelevant thermal effects of the field. For the constant field different time-scales are identified in the conformational, dipole moment, and orientational dynamics. Moreover, we prove that the solvent structure only marginally changes when the external field is switched on. In the case of oscillatory field, the conformational changes are shown to be as strong as in the previous case, and non-trivial nonequilibrium circular paths in the conformation space are revealed by calculating the integrated net probability fluxes.
description: 23 pages, 12 figures
Zoology of instanton solutions in flat potential barriers
Creators: name: Battarra, Lorenzo
name: Lavrelashvili, George
name: Lehners, Jean-Luc
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We perform a detailed study of the existence and the properties of O(4)-invariant instanton solutions in Einstein-scalar theory in the presence of flat potential barriers, i.e. barriers where the second derivative of the potential is small at the top of the barrier. We find a whole zoo of solutions: Hawking-Moss, Coleman-De Luccia (CdL), oscillating instantons, asymmetric CdL as well as other non-standard CdL-like solutions with additional negative modes in their spectrum of fluctuations. Our work shows how these different branches of solutions are connected to each other via "critical" instantons possessing an extra zero mode fluctuation. Overall, the space of finite action euclidean solutions to these theories with flat barriers is surprisingly rich and intricate.
description: 22 pages, 11 figures
Exploring toddlers' ability to learn novel verbs in ditransitive vs transitive frames with three noun phrases
Creators: name: Moscati, VIncenzo
name: Massari, Giulio
name: De Carvalho, Alex
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: First and Second Language Acquisition
subject: Developmental Psychology
subject: Psycholinguistics and Neurolinguistics
subject: Linguistics
subject: FOS: Languages and literature
subject: Syntax
subject: Psychology
subject: FOS: Psychology
subject: Social and Behavioral Sciences

description: In this project we will test toddlers' ability to understand ditransitive frames and use them for learning novel verbs, as predicted by syntactic bootstrapping. Specifically, we will ask whether 30-month-old toddlers can map syntactic positions to specific semantic roles, when processing a 3-NP structure, or whether they rely instead on a rougher kind of linguistic-conceptual mapping. We will test this question on French-learning toddlers, using a dialogue-based Preferential Looking paradigm, implemented via eye-tracking.
The Scenario Approach for Stochastic Model Predictive Control with Bounds on Closed-Loop Constraint Violations
Creators: name: Schildbach, Georg
name: Fagiano, Lorenzo
name: Frei, Christoph
name: Morari, Manfred
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics

description: Many practical applications of control require that constraints on the inputs and states of the system be respected, while optimizing some performance criterion. In the presence of model uncertainties or disturbances, for many control applications it suffices to keep the state constraints at least for a prescribed share of the time, as e.g. in building climate control or load mitigation for wind turbines. For such systems, a new control method of Scenario-Based Model Predictive Control (SCMPC) is presented in this paper. It optimizes the control inputs over a finite horizon, subject to robust constraint satisfaction under a finite number of random scenarios of the uncertainty and/or disturbances. While previous approaches have shown to be conservative (i.e. to stay far below the specified rate of constraint violations), the new method is the first to account for the special structure of the MPC problem in order to significantly reduce the number of scenarios. In combination with a new framework for interpreting the probabilistic constraints as average-in-time, rather than pointwise-in-time, the conservatism is eliminated. The presented method retains the essential advantages of SCMPC, namely the reduced computational complexity and the handling of arbitrary probability distributions. It also allows for adopting sample-and-remove strategies, in order to trade performance against computational complexity.
description: Pre-print submitted to Automatica
User Representation Learning for Personalized Recommendation Systems
Creators: Li, Chenglin
Publisher: name: University of Alberta Library
Year: 2023

Recommendation systems have become an indispensable part of our lives, providing an effective solution to information overload and enhancing user satisfaction by suggesting the most relevant content. In recent years, deep learning has facilitated the creation of recommendation technologies that rely on sophisticated deep neural networks to learn intricate user representations, resulting in remarkable success. However, the existence of persistent issues, such as data sparsity and various biases, presents significant obstacles for deep neural methods in the pursuit of creating effective and unbiased recommendation systems.

Cross-domain recommendation (CDR) is a promising approach that leverages data and knowledge from auxiliary domains to improve the performance of recommender systems when the data in the target domains is sparse. To address the challenge of cross-domain sequential recommendation with limited overlapping users, we developed a novel CDR method inspired by the real-world needs of industrial companies. Our method offers an effective solution to this problem. Furthermore, we extended our CDR approach to multi-target scenarios, where the objective is to enhance recommendation performance for three or more domains simultaneously, and we tackled the issue of negative transfer in this context.

The utilization of a temporal heterogeneous graph is a compelling technique for capturing the intricate interactions between users and items in recommendation systems. In order to achieve precise sequential recommendations through the use of temporal graphs, we introduce a novel continuous-time representation learning model that can extract high-quality user and item representations from a temporal heterogeneous information network. Moreover, to address the issue of biases in recommendation systems, we propose an unbiased sequential recommendation model that incorporates the potential outcome framework (POF) and employs a disentangled graph transformer on a temporal user-item interaction graph to enhance performance.
Finite Element Modeling and Vibration Simulation of a 5-MW 61.5-Meter Composite Wind Turbine Blade for Debonding Damage Inference
Creators: Yang, Junbo
Publisher: name: University of Alberta Library
Year: 2023

The renewable and clean energy industry highly relies on wind turbine blades (WTBs) to generate electricity from wind. However, WTBs can suffer from a variety of damage, including spar cap-shear web debonding, which can lead to crack initiation and propagation, and in turn, cause wind turbine structural collapse. As such, this study focuses on spar cab-shear web debonding by comparing the dynamic behaviors of WTBs with and without debonding via finite element simulations, aiming to shed light on vibration-based damage detection for WTBs. Specifically, this study performed debonding and vibration simulations of the 61.5 m 5-MW blade developed by the National Renewable Energy Laboratory (NREL) in the United States. The objectives of this study are two-fold: (1) to identify the hotspot for cap-web debonding and demonstrate the crack-propagation behavior with an existing crack in the hotspot under increasing aerodynamic loads; (2) to investigate and compare the vibration behaviors of wind turbine blades with and without debonding damage (via free vibration and impact load analysis) to better inform future development of vibration-based diagnostic techniques. It is found that the cap-web connection within a 9-10.25 m span of the studied WTB is more vulnerable to debonding damage and thus determined as the debonding hotspot. The vibration simulation results indicate that the cap-web debonding is less likely to be uncovered by vibration signals, particularly via free vibration testing. However, when impact load testing is used for WTB with relatively large debonding cracks, adequate hitting points and signal collection points (i.e., near crack) can reveal the hidden damage. It is found that when the hitting point is closer to the potential debonding location, more signal discrepancy between the defective WTB and the intact WTB can be observed. Since it is possible to have debonding damage at the following 4 locations in the transverse direction, i.e., within the connection joints between the shear webs and the spar cap located at LE-BOT, LE-TOP, TE-BOT, TE-TOP (herein, LE, TE, BOT, and TOP refer to the leading edge, trailing edge, bottom surface, and top surface of the WTB, respectively), hitting points in impact load tests (e.g., flapwise on the BOT or TOP surfaces, edgewise on the LE or TE) should be located at those 4 locations in the transverse direction. In the spanwise direction, the hitting points within the debonding area, particularly around 10.25 m from the WTB root, are found to be effective for damage detection. Furthermore, the signal collection points should be as close as possible to the hitting points. Such pre-knowledge regarding the debonding hotspot, the relative effectiveness of vibrations methods,

and the impact and vibration signal collection points can potentially increase the effectiveness of vibration-based detection techniques for cap-web debonding in practical applications.
An Exploration of Dialog Act Classification in Open-domain Conversational Agents and the Applicability of Text Data Augmentation
Creators: Sultana, Maliha
Publisher: name: University of Alberta Library
Year: 2023

Recognizing dialog acts of users is an essential component in building successful conversational agents. In this work, we propose a dialog act (DA) classifier for two of our open domain conversational agents. For this, we curated a high-quality, multi-domain dataset with ∼24k user utterances labelled into 8 suitable DAs. Our fine-tuned BERT-based model outperforms the baseline SVM classifier by achieving state-of-the-art accuracy on the proposed dataset. Moreover, it generalizes well on unseen data. To address the issue of data scarcity when training DA classifiers, we implemented different data augmentation techniques and compared their performance. Our extensive experiments show that, in a simulated low data regime with only 10 examples per

label, methods as simple as synonym replacement can double the size of the existing training data and boost accuracy of our DA classifier by ∼8%. Lastly, we demonstrate how our proposed classifier and augmentation techniques can be adapted to effectively detect dialog acts in languages other than English.
Alternative Social Media as an Emerging Social Network: Exploring Alternative Social Media Awareness in Nigeria
Creators: Nwachukwu, Elizabeth O.
Publisher: name: University of Alberta Library
Year: 2023

Commercial Social Media (CSM) platforms like Facebook and Twitter have facilitated online communities and user-generated content, but their dominance has resulted in unethical practices. These include surveillance capitalist business models that exploit user data and "black-box" algorithms that perpetuate hate speech. Despite these concerns, some users remain hesitant to switch to non-commercial social networking platforms due to a lack of awareness or fear of losing their online connections. Although there is a growing uptake of Alternative Social Media (ASM) in the Global North, there is limited research on the awareness and use of ASM in the Global South, particularly sub-Saharan Africa. This research explores existing literature on the adoption of ASM in sub-Saharan Africa, examines the presence of any Fediverse platform in the region, identifies the obstacles that impede their use in Nigeria, and suggests potential remedies to these challenges. I utilized a mixed methods approach that integrated techniques from the Grounded theory methodology and Kleine's choice framework. I collected data through a review of ASM literature, a global audit of Fediverse tracking websites, and semi-structured interviews with current Fediverse administrators in the Global North and potential Fediverse users in sub-Saharan Africa. The findings from this study indicate that there is no literature referring to ASM in sub-Saharan Africa and no known presence of ASM platforms in this region. Based on the input from key informants and scholars, the factors that impact the awareness and use of ASM in Nigeria are: inadequate promotion of Fediverse platforms on traditional media channels, poor user interface, network effects, lack of innovation, and limited access to funding. Study limitations are the small sample size and the challenge of accessing a larger pool of potential participants without travelling to the country.
High repetition rate laser-driven ion acceleration using cryogenic low-Z jets
Creators: Curry, Chandra Breanne
Publisher: name: University of Alberta Library
Year: 2023

Proton and deuteron beams accelerated through high-intensity laser-plasma interactions have the potential to be used in a wide range of applications in research, medicine, and industry. More specifically, they are expected to revolutionize radiography in civil and aerospace engineering and national security applications. They may also supplant nuclear reactors for the production of medical isotopes.

This thesis, completed in the High Energy Density Sciences (HEDS) Division at SLAC National Accelerator Laboratory, has laid the foundation for the creation of bright multi-MeV high-repetition rate proton and deuteron sources. The experimental findings presented herein utilized continuous, high-speed, low-Z cryogenic jets compatible with up to kHz repetition rate petawatt-class laser-plasma interactions. The tunable dimensions, near-critical density, and single-element composition of the cryogenic low-Z jets enable the exploration of previously inaccessible plasma regimes and acceleration mechanisms in the laboratory. They could ultimately be used to produce pulsed charged particle beams with ultra-low emittance and sub-nanosecond pulse durations, thereby surpassing the current state-of-the-art capabilities of large-scale linear accelerators and cyclotrons.

This thesis investigates laser-accelerated ion beams from Target Normal Sheath Acceleration and advanced acceleration regimes with 100-terawatt (TW) and petawatt (PW) class laser systems. Laser-driven ion beams with improved spatial uniformity and high peak brightness have been demonstrated, and this sets a clear path toward the creation of high repetition rate (HRR) laser-driven ion sources.
Implementation of Psychologically Informed Environments (‘PIE’) approaches in UK-based services supporting people experiencing homelessness: a mixed methods systematic review of the evidence
Creators: name: Lemieux-Cumberlege, Aliénor
name: Ridler, Joseph
name: Griffiths, Helen
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Organization Development
subject: Social Work
subject: FOS: Sociology
subject: Community Psychology
subject: Industrial and Organizational Psychology
subject: Psychology
subject: FOS: Psychology
subject: Social and Behavioral Sciences

description: Over the past ten years, the Psychologically Informed Environments (PIEs) framework has become a popular approach to service delivery and practice with people experiencing homelessness. However, there is a dearth of evidence supporting the implementation of this framework, despite anecdotal reports of its utility and effectiveness. This mixed methods systematic review aims to answer the following three questions: 1) What interventions aimed at staff have been used to implement PIE principles in homelessness services? 2) What is the impact of implementing PIE interventions with staff working in homelessness services? 3) What are the barriers and facilitators to implementing PIE approaches in homelessness services?
Supplementary material of “Understanding the transgression of global and regional freshwater planetary boundaries” from Pastor et al. 2022
Creators: name: Pastor, A. V.
name: Biemans, H.
name: Franssen, W.
name: Gerten, D.
name: Hoff, H.
name: Ludwig, F.
name: Kabat, P.
Publisher: name: The Royal Society
Year: 2022
Subjects: Hydrology

description: Freshwater ecosystems have been degraded due to intensive freshwater abstraction. Therefore, environmental flow requirements (EFRs) methods have been proposed to maintain healthy rivers and/or restore river flows. In this study, we used the Variable Monthly Flow (VMF) method to calculate the transgression of freshwater planetary boundaries: (1) natural deficits in which flow does not meet EFRs due to climate variability, and (2) anthropogenic deficits caused by water abstractions. The novelty is that we calculated spatially and cumulative monthly water deficits by river types including the frequency, magnitude and causes of environmental flow (EF) deficits (climatic and/or anthropogenic). Water deficit was found to be a regional rather than a global concern (less than 5% of total discharge). The results show, that, from 1960 to 2000, perennial rivers with low flow alteration, such as the Amazon, had an EF deficit of 2–12% of the total discharge, and that the natural deficit was responsible for up to 75% of the total deficit. In rivers with high seasonality and high water abstractions such as the Indus, the total deficit represents up to 130% of its total discharge, 85% of which is due to withdrawals. We highlight the need to allocate water to humans and ecosystems sustainably.This article is part of the theme issue 'Drought risk in the Anthropocene'.
The Effects of the COVID-19 Pandemic on Preferences for Parks and Personal Space
Creators: Kobori, Hotaka
Publisher: name: University of Alberta Library
Year: 2023

Lockdowns and other non-pharmaceutical interventions that were implemented to combat the COVID-19 Pandemic have had unintended yet profound consequences. One widely-reported consequence has been changes in people’s perceptions of the value of nature and their personal dwelling spaces. Highly publicized anecdotes notwithstanding, the extent of change in people’s preferences for environmental amenities and housing space remains uncertain. Also, how to accurately measure the preference changes is an open question, as conventional methods may not be applicable to this unprecedented event. These evidence gaps have further complicated efforts to address land use management challenges in rapidly growing urban areas such as those found in Western Canada, including Metro Vancouver, Edmonton, and Calgary. This thesis studies the effects of the Pandemic on homeowners’ preferences for environmental amenities and housing space by analyzing changes in housing markets in these three cities. The research critically examines and employs two empirical strategies to a unique and extensive housing transaction dataset from the three regions recorded for the 2017 – 2021 period. Chapter 2 examines the case of Metro Vancouver, while Chapter 3 presents a comparative analysis from the two largest Albertan cities to expand the generalizability of the results. Different empirical approaches generate different results, with our preferred method indicating that changes in the values of open spaces and home attributes vary significantly across housing types and study regions. However, the prices of larger houses, overall, have appreciated most significantly since the Pandemic started. In Vancouver, houses, particularly lower-priced ones, in more heavily treed neighborhoods have become more expensive. This implies, compared to the pre-Pandemic period, the affordability of residence with urban vegetation has worsened, especially for the population who may already have limited access to environmental amenities. In sum, this thesis provides novel and timely insights into the unintended consequences of COVID-19 policies on the value of dwelling spaces and environmental amenities, as well as their potential impacts on the existing disparity in access to green spaces.
Building ID Bridge for Open Science — National PID strategy on CSTR
Creators: name: Liu, Jia
Publisher: name: Zenodo
Year: 2023
Subjects: DataCite Connect Gothenburg 2023
PID Strategies
PID

description: The DataCite Connect event in Gothenburg provides a forum for discussion and networking for DataCite members and the broader community. The session will focus on national PID and Open Research strategies and how the DataCite community can engage in, contribute to, and support their implementation. Participants will learn about ongoing efforts across different regions and will have the chance to work together to identify and discuss alignments between national strategies and their current/future plans that leverage the DataCite infrastructure and services. The outcomes of the meeting will help DataCite members and the community to understand the PID landscape in other regions better, connect with PID champions, and establish new collaborations. There will be plenty of time for Q&A! This event is co-located with the Research Data Alliance 20th Plenary Meeting, 21-23 March 2023, Gothenburg, Sweden, hosted by Chalmers University of Technology, the University of Gothenburg and the Swedish National Data Service (SND). In her presentation, Jia Liu discusses the topic of a national PID strategy in China.
Constraint on Light Dipole Dark Matter from Helioseismology
Creators: name: Lopes, Ilídio
name: Kadota, Kenji
name: Silk, Joseph
Publisher: name: arXiv
Year: 2013
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We investigate the effects of a magnetic dipole moment of asymmetric dark matter (DM) in the evolution of the Sun. The dipole interaction can lead to a sizable DM scattering cross section even for light DM, and the asymmetric dark matter can lead to a large DM number density in the Sun. We find that solar model precision tests, using as diagnostic the sound speed profile obtained from helioseismology data, exclude dipolar dark matter particles with a mass larger than 4.3 GeV and magnetic dipole moment larger than 1.6 $\times \;10^{-17}$ e cm.
description: 2 figures, 4 pages
Exploring the Relationship between Morphological Parameters and Hemodynamic Characteristics in Ascending Thoracic Aortic Aneurysms Using Fluid-Structure Interaction with Patient-specific Models
Creators: Xiao, Meng
Publisher: name: University of Alberta Library
Year: 2023

Ascending thoracic aortic aneurysm (ATAA) is an abnormal bulge in the ascending part of the aorta. It is associated with the risk of dissection and rupture and has been known as the "silent killer". When dissection or rupture, the outcome is usually severe and associated with high mortality. To prevent those adverse events from happening, surgical repair or replacement of the ascending aorta is necessary. The elective surgical criterion must be selected carefully to balance the risk of surgery and the risk of the adverse aortic events associated with ATAA. Current clinical guidelines were purely diameter based and established based on the natural history study of ATAA. However, recent findings have shown that diameter alone is a not good predictor and hence incorporating other parameters such as ascending aortic length (AAL) into the current clinical standard is desired.

With the development of computer technology, computational fluid dynamics and finite elements analysis have emerged as useful tools in cardiovascular studies. By employing those computational methods, researchers could study the interaction of the blood flow with the aortic wall and gain insights into the pathology of ATAA. A pathological flow can trigger vascular remodelling and subsequent wall degeneration, resulting in ATAA formation. In this thesis, we hypothesized that the change in morphology of the aorta results in the worsening of hemodynamic conditions, which subsequently initiates aortic wall degeneration. we perform a comprehensive fluid-structure interaction analysis to simulate the blood-aortic wall interaction.

By assessing the hemodynamic characteristics of ATAA with different morphologies, we confirmed that aortic elongation was associated with the worsening in hemodynamics in ATAA, providing more evidence of using AAL as a surgical indicator. The correlations between AAL and various hemodynamic parameters were comparable to the correlations between diameter and those parameters, meaning that aortic elongation can negatively impact the flow conditions as aortic dilation does. A strong association was also found between the increase in AAV and compromised hemodynamic conditions. Thus, we propose to incorporate AAV, a 3D parameter, into the current clinical elective surgery criterion to account for the variation in the entire aortic geometry instead of just the largest part. Compared with diameter and AAL, AAV showed higher statistical significance and stronger associations with hemodynamic and biomechanical parameters. Hence, by using AAV as an independent or in combination with AAL and diameter, a better prediction might be achieved.
Changing EDSS progression in placebo cohorts in relapsing MS: A systematic review and meta-regression
Creators: name: Röver, Christian
name: Nicholas, Richard
name: Straube, Sebastian
name: Friede, Tim
Publisher: name: arXiv
Year: 2013
Subjects: subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: Background: Recent systematic reviews of randomised controlled trials (RCTs) in relapsing multiple sclerosis (RMS) revealed a decrease in placebo annualized relapse rates (ARR) over the past two decades. Furthermore, regression to the mean effects were observed in ARR and MRI lesion counts. It is unclear whether disease progression measured by the expanded disability status scale (EDSS) exhibits similar features. Methods: A systematic review of RCTs in RMS was conducted extracting data on EDSS and baseline characteristics. The logarithmic odds of disease progression were modelled to investigate time trends. Random-effects models were used to account for between-study variability; all investigated models included trial duration as a predictor to correct for unequal study durations. Meta-regressions were conducted to assess the prognostic value of a number of baseline variables. Results: The systematic literature search identified 39 studies, including a total of 19,714 patients. The proportion of patients in placebo controls experiencing a disease progression decreased over the years (p<0.001). Meta regression identified associated covariates including the size of the study and its duration that in part explained the time trend. Progression probabilities tended to be lower in the second year compared to the first year with a reduction of 24% in progression probability from year 1 to year 2 (p=0.014). Conclusion: EDSS disease progression exhibits similar behaviour over time as the ARR and point to changes in trial characteristics over the years, questioning comparisons between historical and recent trials.
description: 17 pages, 2 figures
Array Antenna Limitations
Creators: name: Jonsson, B. L. G.
name: Kolitsidas, C. I.
name: Hussain, N.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences
subject: 78A50, 78A25

description: This letter defines a physical bound based array figure of merit that provides a tool to compare the performance of both single and multi-band array antennas with respect to return-loss, thickness of the array over the ground-plane, and scan-range. The result is based on a sum-rule result of Rozanov-type for linear polarization. For single-band antennas it extends an existing limit for a given fixed scan-angle to include the whole scan-range of the array, as well as the unit-cell structure in the bound. The letter ends with an investigation of the array figure of merit for some wideband and/or wide-scan antennas with linear polarization. We find arrays with a figure of merit >0.6 that empirically defines high-performance antennas with respect to this measure.
description: Minor changes. Included a pre-page to comply with Journal requirements. Added a few more antennas for which we calculated the array figure of merit