cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Improving the Representativeness of Simulation Intervals for the Cache Memory System
Creators: name: Bueno, Nicolas
name: Castro, Fernando
name: Pinuel, Luis
name: Gomez-Perez, Jose Ignacio
name: Catthoor, Francky
Publisher: name: arXiv
Year: 2024
Subjects: subject: Hardware Architecture (cs.AR)
subject: FOS: Computer and information sciences

description: Accurate simulation techniques are indispensable to efficiently propose new memory or architectural organizations. As implementing new hardware concepts in real systems is often not feasible, cycle-accurate simulators employed together with certain benchmarks are commonly used. However, detailed simulators may take too much time to execute these programs until completion. Therefore, several techniques aimed at reducing this time are usually employed. These schemes select fragments of the source code considered as representative of the entire application's behaviour -- mainly in terms of performance, but not plenty considering the behaviour of cache memory levels -- and only these intervals are simulated. Our hypothesis is that the different simulation windows currently employed when evaluating microarchitectural proposals, especially those involving the last level cache (LLC), do not reproduce the overall cache behaviour during the entire execution, potentially leading to wrong conclusions on the real performance of the proposals assessed. In this work, we first demonstrate this hypothesis by evaluating different cache replacement policies using various typical simulation approaches. Consequently, we also propose a simulation strategy, based on the applications' LLC activity, which mimics the overall behaviour of the cache much closer than conventional simulation intervals. Our proposal allows a fairer comparison between cache-related approaches as it reports, on average, a number of changes in the relative order among the policies assessed -- with respect to the full simulation -- more than 30\% lower than that of conventional strategies, maintaining the simulation time largely unchanged and without losing accuracy on performance terms, especially for memory-intensive applications.
Determining the provenance of software artifacts
Creators: Godfrey, M.
Davis, J.
German, D.
Hindle, Abram
Publisher: name: University of Alberta Library
Year: 2011

Software clone detection has made substantial progress in the last 15 years, and software clone analysis is starting to provide real insight into how and why code clones are born, evolve, and sometimes die. In this position paper, we make the case that there is a more general problem lurking in the background: software artifact provenance analysis. We argue that determining the origin of software artifacts is an increasingly important problem with many dimensions. We call for simple and lightweight techniques that can be used to help narrow the search space, so that more expensive techniques - including manual examination can be used effectively on a smaller candidate set. We predict the problem of software provenance will lead towards new avenues of research for the software clones community.
Dynamical Effects from Anomaly: Modified Electrodynamics in Weyl Semimetal
Creators: name: Ying, Xuzhe
name: Burkov, A. A.
name: Wang, Chong
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We discuss the modified quantum electrodynamics from a time-reversal-breaking Weyl semimetal coupled with a $U(1)$ gauge (electromagnetic) field. A key role is played by the soft dispersion of the photons in a particular direction, say $\hat{z}$, due to the Hall conductivity of the Weyl semimetal. Due to the soft photon, the fermion velocity in $\hat{z}$ is logarithmically reduced under renormalization group flow, together with the fine structure constant. Meanwhile, fermions acquire a finite lifetime from spontaneous emission of the soft photon, namely the Cherenkov radiation. At low energy $E$, the inverse of the fermion lifetime scales as $τ^{-1}\sim E/{\rm PolyLog}(E)$. Therefore, even though fermion quasiparticles are eventually well-defined at very low energy, over a wide intermediate energy window the Weyl semimetal behaves like a marginal Fermi liquid. Phenomenologically, our results are more relevant for emergent Weyl semimetals, where the fermions and photons all emerge from strongly correlated lattice systems. Possible experimental implications are discussed.
description: 8 pages, 4 figures
Gapless symmetry-protected topological phase of quantum antiferromagnets on anisotropic triangular strip
Creators: name: Hidaka, Yuichiro
name: Furuya, Shunsuke C.
name: Ueda, Atsushi
name: Tada, Yasuhiro
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study a three-leg spin-1/2 ladder with geometrically frustrated interleg interactions. We call this model an anisotropic triangular-strip (ATS) model. We numerically and field-theoretically show that its ground state belongs to a gapless symmetry-protected topological (SPT) phase. The numerical approach is based on density-matrix renormalization group analyses of the entanglement entropy and the entanglement spectrum. Whereas the entanglement entropy exhibits a critical behavior, the entanglement spectrum is nontrivially degenerate. These entanglement properties imply that the ground state is a gapless topological phase. We investigate the ATS model using a quantum field theory to support the numerical findings. When the frustrated interchain interaction is deemed a perturbation acting on the three spin chains, the frustrated interchain interaction almost isolates the second chain from the other two chains. However, at the same time, the second chain mediates a ferromagnetic interaction between the first and third chains. Therefore, the ground state of the ATS model is a gapless Tomonaga-Luttinger liquid weakly coupled to a spin-1 Haldane chain with irrelevant interactions. Last but not least, we show that the gapless SPT phase of the ATS model is a symmetry-protected critical phase. We point out that the symmetry protection of criticality is essential in characterization of the gapless SPT phase.
Constraining star formation rates in cool-core brightest cluster galaxies
Creators: name: Mittal, Rupal
name: Whelan, John T.
name: Combes, Francoise
Publisher: name: arXiv
Year: 2015
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We used broad-band imaging data for 10 cool-core brightest cluster galaxies (BCGs) and conducted a Bayesian analysis using stellar population synthesis to determine the likely properties of the constituent stellar populations. Determination of ongoing star formation rates (SFRs), in particular, has a direct impact on our understanding of the cooling of the intracluster medium (ICM), star formation and AGN-regulated feedback. Our model consists of an old stellar population and a series of young stellar components. We calculated marginalized posterior probability distributions for various model parameters and obtained 68% plausible intervals from them. The 68% plausible interval on the SFRs is broad, owing to a wide range of models that are capable of fitting the data, which also explains the wide dispersion in the star formation rates available in the literature. The ranges of possible SFRs are robust and highlight the strength in such a Bayesian analysis. The SFRs are correlated with the X-ray mass deposition rates (the former are factors of 4 to 50 lower than the latter), implying a picture where the cooling of the ICM is a contributing factor to star formation in cool-core BCGs. We find that 9 out of 10 BCGs have been experiencing starbursts since 6 Gyr ago. While four out of 9 BCGs seem to require continuous SFRs, 5 out of 9 seem to require periodic star formation on intervals ranging from 20 Myr to 200 Myr. This time scale is similar to the cooling-time of the ICM in the central (< 5 kpc) regions.
description: 33 pages, 14 Figures, 14 Tables. Accepted for publication in MNRAS
Energy Profiles of Java Collections Classes
Creators: Hasan, S.
King, Z.
Hafiz, M.
Sayagh, M.
Adams, B.
Hindle, Abram
Publisher: name: University of Alberta Library
Year: 2016

We created detailed profiles of the energy consumed by common operations done on Java List, Map, and Set abstractions. The results show that the alternative data types for these abstractions differ significantly in terms of energy consumption depending on the operations. For example, an ArrayList consumes less energy than a LinkedList if items are inserted at the middle or at the end, but consumes more energy than a LinkedList if items are inserted at the start of the list. To explain the results, we explored the memory usage and the bytecode executed during an operation. Expensive computation tasks in the analyzed bytecode traces appeared to have an energy impact, but memory usage did not contribute. We evaluated our profiles by using them to selectively replace Collections types used in six applications and libraries. We found that choosing the wrong Collections type, as indicated by our profiles, can cost even 300% more energy than the most efficient choice. Our work shows that the usage context of a data structure and our measured energy profiles can be used to decide between alternative Collections implementations.
On the Naturalness of Software
Creators: Hindle, Abram
Barr, E.T.
Su, Z.
Devanbu, P.T.
Gabel, M.
Publisher: name: University of Alberta Library
Year: 2012

Natural languages like English are rich, complex, and powerful. The highly creative and graceful use of languages like English and Tamil, by masters like Shakespeare and Avvaiyar, can certainly delight and inspire. But in practice, given cognitive constraints and the exigencies of daily life, most human utterances are far simpler and much more repetitive and predictable. In fact, these utterances can be very usefully modeled using modern statistical methods. This fact has led to the phenomenal success of statistical approaches to speech recognition, natural language translation, question-answering, and text mining and comprehension. We begin with the conjecture that most software is also natural, in the sense that it is created by humans at work, with all the attendant constraints and limitations - and thus, like natural language, it is also likely to be repetitive and predictable. We then proceed to ask whether a) code can be usefully modeled by statistical language models and b) such models can be leveraged to support software engineers. Using the widely adopted n-gram model, we provide empirical evidence supportive of a positive answer to both these questions. We show that code is also very repetitive, and in fact even more so than natural languages. As an example use of the model, we have developed a simple code completion engine for Java that, despite its simplicity, already improves Eclipse's built-in completion capability. We conclude the paper by laying out a vision for future research in this area.
Higgs inflation in Gauss-Bonnet braneworld
Creators: name: Cai, Rong-Gen
name: Guo, Zong-Kuan
name: Wang, Shao-Jiang
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The measured masses of the Higgs boson and top quark indicate that the effective potential of the standard model either develops an unstable electroweak vacuum or stands stable all the way up to the Planck scale. In the latter case in which the top quark mass is about $2σ$ below its present central value, the Higgs boson can be the inflaton with the help of a large nonminimal coupling to curvature in four dimensions. We propose a scenario in which the Higgs boson can be the inflaton in a five-dimensional Gauss-Bonnet braneworld model to solve both the unitarity and stability problems which usually plague Higgs inflation. We find that in order for Higgs inflation to happen successfully in the Gauss-Bonnet regime, the extra dimension scale must appear roughly in the range between the TeV scale and the instability scale of standard model. At the tree level, our model can give rise to a naturally small nonminimal coupling $ξ\sim\mathcal{O}(1)$ for the Higgs quartic coupling $λ\sim\mathcal{O}(0.1)$ if the extra dimension scale lies at the TeV scale. At the loop level, the inflationary predictions at the tree level are preserved. Our model can be confronted with future experiments and observations from both particle physics and cosmology.
description: v1,12 pages,6 figures; v2,final version to match the published version,12 pages,6 figures
Automated Topic Naming Supporting Cross-project Analysis of Software Maintenance Activities
Creators: Hindle, Abram
Ernst, N.A.
Godfrey, M.W.
Mylopoulos, J.
Publisher: name: University of Alberta Library
Year: 2013

Software repositories provide a deluge of software artifacts to analyze. Researchers have attempted to summarize, categorize, and relate these artifacts by using semi-unsupervised machine-learning algorithms, such as Latent Dirichlet Allocation (LDA). LDA is used for concept and topic analysis to suggest candidate word-lists or topics that describe and relate software artifacts. However, these word-lists and topics are difficult to interpret in the absence of meaningful summary labels. Current attempts to interpret topics assume manual labelling and do not use domain-specific knowledge to improve, contextualize, or describe results for the developers. We propose a solution: automated labelled topic extraction. Topics are extracted using LDA from commit-log comments recovered from source control systems. These topics are given labels from a generalizable cross-project taxonomy, consisting of non-functional requirements. Our approach was evaluated with experiments and case studies on three large-scale Relational Database Management System (RDBMS) projects: MySQL, PostgreSQL and MaxDB. The case studies show that labelled topic extraction can produce appropriate, context-sensitive labels that are relevant to these projects, and provide fresh insight into their evolving software development activities.
Non-Gaussian signatures and collective effects in charge noise affecting a dynamically-decoupled qubit
Creators: name: Ramon, Guy
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The effects of a collection of classical two-level charge fluctuators on the coherence of a dynamically-decoupled qubit are studied. Distinct dynamics are found at different qubit working positions. Exact analytical formulae are derived at pure dephasing and approximate solutions are found at the general working position, for weakly- and strongly-coupled fluctuators. Analysis of these solutions, combined with numerical simulations of the multiple random telegraph processes, reveal the scaling of the noise with the number of fluctuators and the number of control pulses, as well as dependence on other parameters of the qubit-fluctuators system. These results can be used to determine potential microscopic models for the charge environment by performing noise spectroscopy.
description: 18 pages, 9 figures
GreenMiner: a hardware based mining software repositories software energy consumption framework
Creators: Hindle, Abram
Wilson, A.
Rasmussen, K.
Barlow, E.J.
Campbell, J.
Romansky, S.
Publisher: name: University of Alberta Library
Year: 2014

Green Mining is a field of MSR that studies software energy consumption and relies on software performance data. Unfortunately there is a severe lack of publicly available software power use performance data. This means that green mining researchers must generate this data themselves by writing tests, building multiple revisions of a product, and then running these tests multiple times (10+) for each software revision while measuring power use. Then, they must aggregate these measurements to estimate the energy consumed by the tests for each software revision. This is time consuming and is made more difficult by the constraints of mobile devices and their OSes. In this paper we propose, implement, and demonstrate Green Miner: the first dedicated hardware mining software repositories testbed. The Green Miner physically measures the energy consumption of mobile devices (Android phones) and automates the testing of applications, and the reporting of measurements back to developers and researchers. The Green Miner has already produced valuable results for commercial Android application developers, and has been shown to replicate other power studies' results.
Detecting duplicate bug reports with software engineering domain knowledge
Creators: Aggarwal, K.
Rutgers, T.
Timbers, F.
Hindle, Abram
Greiner, R.
Stroulia, E.
Publisher: name: University of Alberta Library
Year: 2015

In previous work by Alipour et al., a methodology was proposed for detecting duplicate bug reports by comparing the textual content of bug reports to subject-specific contextual material, namely lists of software-engineering terms, such as non-functional requirements and architecture keywords. When a bug report contains a word in these word-list contexts, the bug report is considered to be associated with that context and this information tends to improve bug-deduplication methods. In this paper, we propose a method to partially automate the extraction of contextual word lists from software-engineering literature. Evaluating this software-literature context method on real-world bug reports produces useful results that indicate this semi-automated method has the potential to substantially decrease the manual effort used in contextual bug deduplication while suffering only a minor loss in accuracy.
The Gut-Brain Axis in Healthy Females: Lack of Significant Association between Microbial Composition and Diversity with Psychiatric Measures
Creators: name: Glenny, Elaine M.
name: Huh, Eun Young
name: Carroll, Ian M.
name: Zerwas, Stephanie C.
name: Bulik, Cynthia M.
name: Bulik-Sullivan, Emily C.
name: Fodor, Anthony A.
name: Kleiman, Susan C.
name: Tsilimigras, Matthew C.B.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: This study examined associations between the composition and diversity of the intestinal microbiota and measures of depression, anxiety, eating disorder psychopathology, stress, and personality in a group of healthy adult females.
Search for optimal driving in finite quantum systems with precursors of criticality
Creators: name: Matus, Felipe
name: Střeleček, Jan
name: Stránský, Pavel
name: Cejnar, Pavel
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Using the adiabatic perturbation theory of driven dynamics [Phys. Rev. A 78, 052508 (2008)] we design a hierarchy of quantum state preparation protocols that systematically increase the fidelity at very long driving times. We test these and other protocols, including those based on the geometric analysis of the parameter space, in a single-qubit system and in a fully connected multi-qubit system showing in its infinite-size limit several quantum phase transitions. The new protocols excel in the asymptotic driving regime, above a crossover time from the Landau-Zener regime which increases with a decreasing minimal energy gap along the driving path (with the size of the system). In the medium-time domain, the performance of all tested protocols is indecisive.
description: 16 pages, 14 figures
Relating Requirements to Implementation via Topic Analysis: Do Topics Extracted from Requirements Make Sense to Managers and Developers?
Creators: Hindle, Abram
Bird, C.
Zimmermann, T.
Nagappan, N.
Publisher: name: University of Alberta Library
Year: 2012

Large organizations like Microsoft tend to rely on formal requirements documentation in order to specify and design the software products that they develop. These documents are meant to be tightly coupled with the actual implementation of the features they describe. In this paper we evaluate the value of high-level topic-based requirements traceability in the version control system, using Latent Dirichlet Allocation (LDA). We evaluate LDA topics on practitioners and check if the topics and trends extracted matches the perception that Program Managers and Developers have about the effort put into addressing certain topics. We found that effort extracted from version control that was relevant to a topic often matched the perception of the managers and developers of what occurred at the time. Furthermore we found evidence that many of the identified topics made sense to practitioners and matched their perception of what occurred. But for some topics, we found that practitioners had difficulty interpreting and labelling them. In summary, we investigate the high-level traceability of requirements topics to version control commits via topic analysis and validate with the actual stakeholders the relevance of these topics extracted from requirements.
Competition between pairing and tripling in one-dimensional fermions with coexistent s- and p-wave interactions
Creators: name: Guo, Yixin
name: Tajima, Hiroyuki
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We theoretically investigate in-medium two- and three-body correlations in one-dimensional two-component Fermi gases with coexistent even-parity s-wave and odd-parity p-wave interactions. We find the solutions of the stable in-medium three-body cluster states such as Cooper triple by solving the corresponding in-medium variational equations. We further feature the phase diagram consisting of the s- and p-wave Cooper pairing phase, and Cooper tripling phase, in the plane of s- and p-wave pairing strengths. The Cooper tripling phase dominates over the pairing phases when both s- and p-wave interactions are moderately strong.
description: 7 pages, 3 figures
Software Bertillonage Determining the Provenance of Software Development Artifacts
Creators: Davies, J.
German, D.M.
Godfrey, M.W.
Hindle, Abram
Publisher: name: University of Alberta Library
Year: 2012

Deployed software systems are typically composed of many pieces, not all of which may have been created by the main development team. Often, the provenance of included components—such as external libraries or cloned source code—is not clearly stated, and this uncertainty can introduce technical and ethical concerns that make it difficult for system owners and other stakeholders to manage their software assets. In this work, we motivate the need for the recovery of the provenance of software entities by a broad set of techniques that could include signature matching, source code fact extraction, software clone detection, call flow graph matching, string matching, historical analyses, and other techniques. We liken our provenance goals to that of Bertillonage, a simple and approximate forensic analysis technique based on bio-metrics that was developed in 19th century France before the advent of fingerprints. As an example, we have developed a fast, simple, and approximate technique called anchored signature matching for identifying the source origin of binary libraries within a given Java application. This technique involves a type of structured signature matching performed against a database of candidates drawn from the Maven2 repository, a 275 GB collection of open source Java libraries. To show the approach is both valid and effective, we conducted an empirical study on 945 jars from the Debian GNU/Linux distribution, as well as an industrial case study on 81 jars from an e-commerce application.
Additional file 7 of A scoping review of health literacy in rare disorders: key issues and research directions
Creators: name: Stenberg, Una
name: Westfal, Lydia
name: Dybesland Rosenberger, Andreas
name: Ørstavik, Kristin
name: Flink, Maria
name: Holmen, Heidi
name: Systad, Silje
name: Westermann, Karl Fredrik
name: Velvin, Gry
Publisher: name: figshare
Year: 2024
Subjects: subject: Medicine
subject: Sociology
subject: FOS: Sociology
subject: Cancer
subject: Science Policy
subject: Mental Health

description: Supplementary Material 7
Quasistatic and Pulsed Current-Induced Switching with Spin-Orbit Torques in Ultrathin Films with Perpendicular Magnetic Anisotropy
Creators: name: Hung, Yu-Ming
name: Rehm, Laura
name: Wolf, Georg
name: Kent, Andrew D.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Spin-orbit interaction derived spin torques provide a means of reversing the magnetization of perpendicularly magnetized ultrathin films with currents that flow in the plane of the layers. A basic and critical question for applications is the speed and efficiency of switching with nanosecond current pulses. Here we investigate and contrast the quasistatic (slowly swept current) and pulsed current-induced switching characteristics of micron scale Hall crosses consisting of very thin ($<1$ nm) perpendicularly magnetized CoFeB layers on $β$-Ta. While complete magnetization reversal is found at a threshold current density in the quasistatic case, short duration ($\leq 10$ ns) larger amplitude pulses ($\simeq 10 \times$ the quasistatic threshold current) lead to only partial magnetization reversal and domain formation. We associate the partial reversal with the limited time for reversed domain expansion during the pulse.
Exact solution to two-body financial dealer model: revisited from the viewpoint of kinetic theory
Creators: name: Kanazawa, Kiyoshi
name: Takayasu, Hideki
name: Takayasu, Misako
Publisher: name: arXiv
Year: 2022
Subjects: subject: Trading and Market Microstructure (q-fin.TR)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Economics and business
subject: FOS: Physical sciences

description: The two-body stochastic dealer model is revisited to provide an exact solution to the average order-book profile using the kinetic approach. The dealer model is a microscopic financial model where individual traders make decisions on limit-order prices stochastically and then reach agreements on transactions. In the literature, this model was solved for several cases: an exact solution for two-body traders $N=2$ and a mean-field solution for many traders $N\gg 1$. Remarkably, while kinetic theory plays a significant role in the mean-field analysis for $N\gg 1$, its role is still elusive for the case of $N=2$. In this paper, we revisit the two-body dealer model $N=2$ to clarify the utility of the kinetic theory. We first derive the exact master-Liouville equations for the two-body dealer model by several methods. We next illustrate the physical picture of the master-Liouville equation from the viewpoint of the probability currents. The master-Liouville equations are then solved exactly to derive the order-book profile and the average transaction interval. Furthermore, we introduce a generalised two-body dealer model by incorporating interaction between traders via the market midprice and exactly solve the model within the kinetic framework. We finally confirm our exact solution by numerical simulations. This work provides a systematic mathematical basis for the econophysics model by developing better mathematical intuition.
description: 40 pages, 15 figures
The medically managed patient with severe symptomatic aortic stenosis in the TAVR era: Patient characteristics, reasons for medical management, and quality of shared decision making at heart valve treatment centers
Creators: name: Foster, Jill
name: Dharmarajan, Kumar
name: Huang, Pei-Hsiu
name: Thourani, Vinod H.
name: Faheem, Osman
name: Coylewright, Megan
name: Mccoy, Lisa
name: Wang, Tracy Y.
name: Krishnaswamy, Amar
name: Vavalle, John P.
name: Green, Philip
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Little is known about patients with severe symptomatic aortic stenosis (AS) who receive medical management despite evaluation at a heart valve treatment center.
Highly anisotropic magnetism in the vanadium-based kagome metal TbV6Sn6
Creators: name: Pokharel, Ganesh
name: Ortiz, Brenden
name: Chamorro, Juan
name: Sarte, Paul
name: Kautzsch, Linus
name: Wu, Guang
name: Ruff, Jacob
name: Wilson, Stephen D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: RV6Sn6 (R=rare earth) compounds are appealing materials platforms for exploring the interplay between R-site magnetism and nontrivial band topology associated with the nonmagnetic vanadium-based kagome network. Here we present the synthesis and characterization of the kagome metal TbV6Sn6 via single-crystal x-ray diffraction, magnetization, transport, and heat capacity measurements. Magnetization measurements reveal strong, uniaxial magnetic anisotropy rooted in the alignment of Tb3Å moments in the interplane direction below 4.3(2) K. TbV6Sn6 exhibits multiband transport behavior with high mobilities of charge carriers, and our measurements suggest TbV6Sn6 is a promising candidate for hosting Chern gaps driven via the interplay between Tb-site magnetic order and the band topology of the V-site kagome network.
Theory of Energy Dispersion of Chiral Phonon
Creators: name: Tsunetsugu, Hirokazu
name: Kusunose, Hiroaki
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We have developed a microscopic theory on phonon energy dispersion in chiral crystals within a harmonic approximation. One of the main issues is about the splitting of sound velocity of acoustic phonons with opposite ``crystal'' angular momentum. We have shown that the splitting must be zero even in chiral crystals and the difference starts from the order of at least $k^2$ or higher in their energy dispersion. Splitting is evident for chiral optical phonons, and we have derived a formula for their $k$-linear splitting. Another important finding is about possible interactions of atomic displacements in microscopic models. We have found that antisymmetric interactions of $\mathbf{D} _{ij} \cdot (\mathbf{d} _i \times \mathbf{d} _j) $ type are not allowed in microscopic Hamiltonians for chiral phonons in compatible with the stability against the Nambu-Goldstone mode. We have identified that the splitting in both acoustic and optical modes arises from the harmonic potentials with the electric toroidal quadrupole of $G_{u}$-type symmetry. These constraint are important for modeling real materials. Most of our microscopic calculations have been performed for (quasi-)one-dimensional systems with a trigonal crystal symmetry including Te, but these results generally hold also for other chiral phonon systems.
description: 5 pages, 3 figures. To be published in J. Phys. Soc. Jpn
Co-evolution of project documentation and popularity within github
Creators: Aggarwal, K.
Hindle, Abram
Stroulia, E.
Publisher: name: University of Alberta Library
Year: 2014

Github is a very popular collaborative software-development platform that provides typical source-code management and issue tracking features augmented by strong social-networking features such as following developers and watching projects. These features help "spread the word" about individuals and projects, building the reputation of the former and increasing the popularity of the latter. In this paper, we investigate the relation between project popularity and regular, consistent documentation updates. We found strong indicators that consistently popular projects exhibited consistent documentation effort and that this effort tended to attract more documentation collaborators. We also found that frameworks required more documentation effort than libraries to achieve similar adoption success, especially in the initial phase.
Dynamics of Ion Temperature Gradient Turbulence and Transport with a Static Magnetic Island
Creators: name: Izacard, Olivier
name: Holland, Christopher
name: James, Spencer D.
name: Brennan, Dylan P.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Understanding the interaction mechanisms between large-scale magnetohydrodynamic instabilities and small-scale drift-wave microturbulence is essential for predicting and optimizing the performance of magnetic confinement based fusion energy experiments. We report progress on understanding these interactions using both analytic theory and numerical simulations performed with the BOUT++ [B. Dudson et al., Comput. Phys. Comm. 180, 1467 (2009)] framework. This work focuses upon the dynamics of the ion temperature gradient instability in the presence of a background static magnetic island, using a weakly electromagnetic two-dimensional five-field fluid model. It is found that the island width must exceed a threshold size (comparable to the turbulent correlation length in the no-island limit) to significantly impact the turbulence dynamics, with the primary impact being an increase in turbulent fluctuation and heat flux amplitudes. The turbulent radial ion energy flux is shown to localize near the X-point, but does so asymmetrically in the poloidal dimension. An effective turbulent resistivity which acts upon the island outer layer is also calculated, and shown to always be significantly (10x - 100x) greater than the collisional resistivity used in the simulations.
description: 14 pages, 35 figures
Robustness of cosmic birefringence measurement against Galactic foreground emission and instrumental systematics
Creators: name: Diego-Palazuelos, P.
name: Martínez-González, E.
name: Vielva, P.
name: Barreiro, R. B.
name: Tristram, M.
name: de la Hoz, E.
name: Eskilt, J. R.
name: Minami, Y.
name: Sullivan, R. M.
name: Banday, A. J.
name: Górski, K. M.
name: Keskitalo, R.
name: Komatsu, E.
name: Scott, D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The polarization of the cosmic microwave background (CMB) can be used to search for parity-violating processes like that predicted by a Chern-Simons coupling to a light pseudoscalar field. Such an interaction rotates $E$ modes into $B$ modes in the observed CMB signal by an effect known as cosmic birefringence. Even though isotropic birefringence can be confused with the rotation produced by a miscalibration of the detectors' polarization angles the degeneracy between both effects is broken when Galactic foreground emission is used as a calibrator. In this work, we use realistic simulations of the High-Frequency Instrument of the Planck mission to test the impact that Galactic foreground emission and instrumental systematics have on the recent birefringence measurements obtained through this technique. Our results demonstrate the robustness of the methodology against the miscalibration of polarization angles and other systematic effects, like intensity-to-polarization leakage, beam leakage, or cross-polarization effects. However, our estimator is sensitive to the $EB$ correlation of polarized foreground emission. Here we propose to correct the bias induced by dust $EB$ by modeling the foreground signal with templates produced in Bayesian component-separation analyses that fit parametric models to CMB data. Acknowledging the limitations of currently available dust templates like that of the Commander sky model, high-precision CMB data and a characterization of dust beyond the modified blackbody paradigm are needed to obtain a definitive measurement of cosmic birefringence in the future.
description: 36 pages, 19 figures, matches the version accepted for publication at JCAP
Lattice QCD calculation of light sterile neutrino contribution in $0\nu2β$ decay
Creators: name: Tuo, Xin-Yu
name: Feng, Xu
name: Jin, Lu-Chang
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present a lattice QCD study of the neutrinoless double beta decay involving light sterile neutrinos. The calculation is performed at physical pion mass using five gauge ensembles generated with the $2+1$-flavor domain wall fermions. We obtain the low-energy constants $g_{\text{LR}}^{ππ}(m_ν)$ with the neutrino mass $m_ν$ from $0$ GeV to $3$ GeV. The lattice results are reasonably consistent with the previous interpolation method with a $\sim20\%$ deviation at small $m_ν$. We provide an explanation on the discrepancy at vanishing neutrino mass. At large $m_ν$, a good consistence between our results and the previous lattice determination of $g_{4}^{ππ}(μ)$ is found at $μ=m_ν=3$ GeV.
description: 19 pages, 5 figures
The N-terminal domains of FLASH and Lsm11 form a 2:1 heterotrimer for histone pre-mRNA 3’-end processing
Creators: name: Tong, Liang
name: Marzluff, William F.
name: Tan, Dazhi
name: Chou, Chi-Yuan
name: Lin, Min-Han
name: Tripathy, Ashutosh
name: Aik, Wei Shen
name: Dominski, Zbigniew
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Unlike canonical pre-mRNAs, animal replication-dependent histone pre-mRNAs lack introns and are processed at the 3’-end by a mechanism distinct from cleavage and polyadenylation. They have a 3’ stem loop and histone downstream element (HDE) that are recognized by stem-loop binding protein (SLBP) and U7 snRNP, respectively. The N-terminal domain (NTD) of Lsm11, a component of U7 snRNP, interacts with FLASH NTD and these two proteins recruit the histone cleavage complex containing the CPSF-73 endonuclease for the cleavage reaction. Here, we determined crystal structures of FLASH NTD and found that it forms a coiled-coil dimer. Using solution light scattering, we characterized the stoichiometry of the FLASH NTD-Lsm11 NTD complex and found that it is a 2:1 heterotrimer, which is supported by observations from analytical ultracentrifugation and crosslinking.
A note on the possible bound $D^{(\ast)} D ^{(\ast)}, \bar{B}^{(\ast)} \bar{B}^{(\ast)} $ and $D^{(\ast)} \bar{B}^{(\ast)} $ states
Creators: name: Abreu, Luciano M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Motivated by the recently observation of the tetraquark $T_{cc}^+ $ state, in this work I revisit the Heavy-Meson Effective Theory to perform a simplified field-theoretical study of possible deuteron-like $D^{(\ast)} D ^{(\ast)}, \bar{B}^{(\ast)} \bar{B}^{(\ast)} $ and $D^{(\ast)} \bar{B}^{(\ast)} $ molecules. In particular, using the data from $T_{cc}^+ $ as input to fix the potential associated to the shallow-bound $ D D^{*} $ system with $I(J^P) = 1(1^+)$, the conditions for the formation of other loosely-bound states in the doubly charmed sector are analyzed. The other sectors are also discussed.
description: 13 pages; 3 figures
Creating and controlling exceptional points of non-Hermitian Hamiltonians via homodyne Lindbladian invariance
Creators: name: Minganti, Fabrizio
name: Huybrechts, Dolf
name: Elouard, Cyril
name: Nori, Franco
name: Arkhipov, Ievgen I.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The Exceptional Points (EPs) of non-Hermitian Hamiltonians (NHHs) are spectral degeneracies associated with coalescing eigenvalues and eigenvectors which are associated with remarkable dynamical properties. These EPs can be generated experimentally in open quantum systems, evolving under a Lindblad equation, by postselecting on trajectories that present no quantum jumps, such that the dynamics is ruled by a NHH. Interestingly, changing the way the information used for postselection is collected leads to different unravelings, i.e., different set of trajectories which average to the same Lindblad equation, but are associated with a different NHH. Here, we exploit this mechanism to create and control EPs solely by changing the measurement we postselect on. Our scheme is based on a realistic homodyne reading of the emitted leaking photons with a weak-intensity laser (a process which we call $β$-dyne), which we show generates a tunable NHH, that can exhibit EPs even though the system does have any in the absence of the laser. We consider a few illustrative examples pointing the dramatic effects that different postselections can have on the spectral features of the NHH, paving the road towards engineering of EPs in simple quantum systems.
Automated topic naming to support cross-project analysis of software maintenance activities
Creators: Hindle, Abram
Ernst, N.
Godfrey, M.M.
Mylopoulos, J.
Publisher: name: University of Alberta Library
Year: 2011

Researchers have employed a variety of techniques to extract underlying topics that relate to software development artifacts. Typically, these techniques use semi-unsupervised machine-learning algorithms to suggest candidate word-lists. However, word-lists are difficult to interpret in the absence of meaningful summary labels. Current topic modeling techniques assume manual labelling and do not use domainspecific knowledge to improve, contextualize, or describe results for the developers. We propose a solution: automated labelled topic extraction. Topics are extracted using Latent Dirichlet Allocation (LDA) from commit-log comments recovered from source control systems such as CVS and Bit-Keeper. These topics are given labels from a generalizable cross-project taxonomy, consisting of non-functional requirements. Our approach was evaluated with experiments and case studies on two large-scale RDBMS projects: MySQL and MaxDB. The case studies show that labelled topic extraction can produce appropriate, context-sensitive labels relevant to these projects, which provides fresh insight into their evolving software development activities.
The Creativity of Text-to-Image Generation
Creators: name: Oppenlaender, Jonas
Publisher: name: arXiv
Year: 2022
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: Graphics (cs.GR)
subject: FOS: Computer and information sciences
subject: H.5; H.m

description: Text-guided synthesis of images has made a giant leap towards becoming a mainstream phenomenon. With text-to-image generation systems, anybody can create digital images and artworks. This provokes the question of whether text-to-image generation is creative. This paper expounds on the nature of human creativity involved in text-to-image art (so-called "AI art") with a specific focus on the practice of prompt engineering. The paper argues that the current product-centered view of creativity falls short in the context of text-to-image generation. A case exemplifying this shortcoming is provided and the importance of online communities for the creative ecosystem of text-to-image art is highlighted. The paper provides a high-level summary of this online ecosystem drawing on Rhodes' conceptual four P model of creativity. Challenges for evaluating the creativity of text-to-image generation and opportunities for research on text-to-image generation in the field of Human-Computer Interaction (HCI) are discussed.
Detecting duplicate bug reports with software engineering domain knowledge
Creators: Aggarwal, K.
Timbers, F.
Rutgers, T.
Hindle, Abram
Stroulia, E.
Greiner, R.
Publisher: name: University of Alberta Library
Year: 2017

Bug deduplication, ie, recognizing bug reports that refer to the same problem, is a challenging task in the software-engineering life cycle. Researchers have proposed several methods primarily relying on information-retrieval techniques. Our work motivated by the intuition that domain knowledge can provide the relevant context to enhance effectiveness, attempts to improve the use of information retrieval by augmenting with software-engineering knowledge. In our previous work, we proposed the software-literature-context method for using software-engineering literature as a source of contextual information to detect duplicates. If bug reports relate to similar subjects, they have a better chance of being duplicates. Our method, being largely automated, has a potential to substantially decrease the level of manual effort involved in conventional techniques with a minor trade-off in accuracy.

In this study, we extend our work by demonstrating that domain-specific features can be applied across projects than project-specific features demonstrated previously while still maintaining performance. We also introduce a hierarchy-of-context to capture the software-engineering knowledge in the realms of contextual space to produce performance gains. We also highlight the importance of domain-specific contextual features through cross-domain contexts: adding context improved accuracy; Kappa scores improved by at least 3.8% to 10.8% per project.
Energy Efficient Guidelines for iOS Core Location Framework
Creators: Bangash, A.A.
Tiganov, D.
Ali, K.
Hindle, Abram
Publisher: name: University of Alberta Library
Year: 2021

Several types of apps require accessing user location, including map navigation, food ordering, and fitness tracking apps. To access user location, app developers use frameworks that the underlying platform provides to them. For the iOS platform, the Core Location framework enables developers to configure various services to obtain user location information. But how does a particular configuration affect the energy consumption of an app? The available Core Location framework documentation is insufficient to help developers reason about the tradeoff between choosing a particular configuration and energy consumption. In this paper, we present a set of guidelines that will help developers make an energy-efficient design choice while configuring the Core Location framework for their app. To achieve that, we have created microbenchmark configurations of the various services that the Core Location framework provides. We have then run several test-scenarios on these configurations to extract their energy profiles. To extract energy-efficient guidelines for developers, we have carefully examined those energy profile results. The guidelines show several configurations that not only reduce energy consumption but also access locations more frequently than other configurations. To evaluate those guidelines, we analyzed three real-world apps and a location service sample app provided by Apple. Our results show that the guidelines help reduce energy: 0.42% for a property search app, 10.59% for a weather app, 26.91% for a location utility app, and 11.37% for Apple's sample app. Additionally, our empirical evaluation shows that choosing an energy-hungry configuration can increase the energy consumption by up to a maximum of 23.97%. Our guidelines are effective on 3 real-world apps, and our methodology may be used to extract energy-efficient guidelines for frameworks other than the Core Location framework.