cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Additional file 1 of Transcranial magnetic stimulation and transcranial direct current stimulation affect explicit but not implicit emotion regulation: a meta-analysis
Creators: name: Qiu, Xiufu
name: He, Zhenhong
name: Cao, Xueying
name: Zhang, Dandan
Publisher: name: figshare
Year: 2024
Subjects: Biological Sciences not elsewhere classified
Science Policy
Mental Health

description: Additional file 1: Table S1. Characteristics of inhibitory TMS of explicit and implicit ER studies. Table S2. Characteristics of cathode tDCS of explicit and implicit ER studies. Table S3. The effect of excitatory and inhibitory TMS and tDCS on the no-regulation condition of explicit ER. Table S4. The effect of excitatory and inhibitory TMS and tDCS on the no-regulation condition of implicit ER. Figure S1. Risk of bias summary of all included studies (n = 6). (A) Methodological quality assessment of each study at 6 domains was illustrated. (B) Risk of bias graph. Figure S2. Forest plot for the summary effect size on the effect of inhibitory TMS and tDCS on the subjective experience of down-regulation. Combied: Studies with multiple outcomes within a study were combined into averaged data with CMA, which can prevent an improper estimate of the precision of the summary effect. Figure S3. Forest plot for the summary effect size on the effect of inhibitory TMS and tDCS on subjective experience of up-regulation. Figure S4. Forest plot for the summary effect size on the effect of inhibitory TMS and tDCS on subjective experience of implicit ER. Combied: Studies with multiple outcomes (e.g. valence and arousal) within a study were combined into averaged data with CMA, which can prevent an improper estimate of the precision of the summary effect. Figure S5. Sensitivity analysis with one study removed for the excitatory TMS and tDCS effect on the subjective experience of down-regulation. Figure S6. Sensitivity analysis with one study removed for the excitatory TMS and tDCS effect on the physiological response of down-regulation. Figure S7. Sensitivity analysis with one study removed for the excitatory TMS and tDCS effect on the subjective experience of up-regulation. Figure S8. Sensitivity analysis with one study removed for the excitatory TMS and tDCS effect on the physiological response of implicit ER.
Learning and Recognizing The Hierarchical and Sequential Structure of Human Activities
Creators: name: Heng-Tze  Cheng
Publisher: name: Figshare
Year: 2018
Subjects: subject: Computer Engineering
subject: 90699 Electrical and Electronic Engineering not elsewhere classified
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The mission of the research presented in this thesis is to give computers the power to sense and react to human activities. Without the ability to sense the surroundings and understand what humans are doing, computers will not be able to provide active, timely, appropriate, and considerate services to the humans. To accomplish this mission, the work stands on the shoulders of two giants: Machine learning and ubiquitous computing. Because of the ubiquity of sensor-enabled mobile and wearable devices, there has been an emerging opportunity to sense, learn, and infer human activities from the sensor data by leveraging state-of-the-art machine learning algorithms.
While having shown promising results in human activity recognition, most existing approaches using supervised or semi-supervised learning have two fundamental problems. Firstly, most existing approaches require a large set of labeled sensor data for every target class, which requires a costly effort from human annotators. Secondly, an unseen new activity cannot be recognized if no training samples of that activity are available in the dataset. In light of these problems, a new approach in this area is proposed in our research.
This thesis presents our novel approach to address the problem of human activity recognition when few or no training samples of the target activities are available. The main hypothesis is that the problem can be solved by the proposed NuActiv activity recognition framework, which consists of modeling the hierarchical and sequential structure of human activities, as well as bringing humans in the loop of model training. By injecting human knowledge about the hierarchical nature of human activities, a semantic attribute representation and a two-layer attribute-based learning approach are designed. To model the sequential structure, a probabilistic graphical model is further proposed to take into account the temporal dependency of activities and attributes. Finally, an active learning algorithm is developed to reinforce the recognition accuracy using minimal user feedback.
The hypothesis and approaches presented in this thesis are validated by two case studies and real-world experiments on exercise activities and daily life activities. Experimental results show that the NuActiv framework can effectively recognize unseen new activities even without any training data, with up to 70-80% precision and recall rate. It also outperforms supervised learning with limited labeled data for the new classes. The results significantly advance the state of the art in human activity recognition, and represent a promising step towards bridging the gap between computers and humans.
Universality, Lee-Yang Singularities, and Series Expansions
Creators: name: Başar, G.
Publisher: name: American Physical Society
Year: 2021

description: We introduce a new way of reconstructing the equation of state of a thermodynamic system near a second-order critical point from a finite set of Taylor coefficients computed away from the critical point. We focus on the Ising universality class ( symmetry) and show that, in the crossover region of the phase diagram, it is possible to efficiently extract the location of the nearest thermodynamic singularity, the Lee-Yang edge singularity, from which one can (i) determine the location of the critical point, (ii) constrain the nonuniversal parameters that maps the equation of state to that of the Ising model in the scaling regime, and (iii) numerically evaluate the equation of state in the vicinity of the critical point. This is done by using a combination of Padé resummation and conformal maps. We explicitly demonstrate these ideas in the celebrated Gross-Neveu model.
Encoding information in the mutual coherence of spatially separated light beams
Creators: name: Nardi, Alfonso
name: Divitt, Shawn
name: Rossi, Massimiliano
name: Tebbenjohanns, Felix
name: Militaru, Andrei
name: Frimmer, Martin
name: Novotny, Lukas
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: Signal Processing (eess.SP)
subject: FOS: Physical sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Coherence has been used as a resource for optical communications since its earliest days. It is widely used for multiplexing of data, but not for encoding of data. Here we introduce a coding scheme, which we call \textit{mutual coherence coding}, to encode information in the mutual coherence of spatially separated light beams. We describe its implementation and analyze its performance by deriving the relevant figures of merit (signal-to-noise ratio, maximum bit-rate, and spectral efficiency) with respect to the number of transmitted beams. Mutual coherence coding yields a quadratic scaling of the number of transmitted signals with the number of employed light beams, which might have benefits for cryptography and data security.
Evolution of Non-Gaussian Hydrodynamic Fluctuations
Creators: name: Stephanov, M.
name: Yee, H.-U.
name: An, X.
name: Başar, G.
Publisher: name: American Physical Society
Year: 2021

description: In the context of the search for the QCD critical point using non-Gaussian fluctuations, we obtain the evolution equations for non-Gaussian cumulants to the leading order of the systematic expansion in the magnitude of thermal fluctuations. We develop a diagrammatic technique in which the leading order contributions are given by tree diagrams. We introduce a Wigner transform for multipoint correlators and derive the evolution equations for three- and four-point Wigner functions for the problem of nonlinear stochastic diffusion with multiplicative noise.
Learning Large-Scale Conditional Random Fields
Creators: name: Bradley, Joseph K.
Publisher: name: Figshare
Year: 2018
Subjects: subject: 170203 Knowledge Representation and Machine Learning
subject: FOS: Psychology

description: Conditional Random Fields (CRFs) [Lafferty et al., 2001] can offer computational and statistical advantages over generative models, yet traditional CRF parameter and structure learning methods are often too expensive to scale up to large problems. This thesis develops methods capable of learning CRFs for much larger problems. We do so by decomposing learning problems into smaller, simpler subproblems. These decompositions allow us to trade off sample complexity, computational complexity, and potential for parallelization, and we can often optimize these trade-offs in model- or data-specific ways. The resulting methods are theoretically motivated, are often accompanied by strong guarantees, and are effective and highly scalable in practice.
In the first part of our work, we develop core methods for CRF parameter and structure learning. For parameter learning, we analyze several methods and produce PAC learnability results for certain classes of CRFs. Structured composite likelihood estimation proves particularly successful in both theory and practice, and our results offer guidance for optimizing estimator structure. For structure learning, we develop a maximum-weight spanning tree-based method which outperforms other methods for recovering tree CRFs. In the second part of our work, we take advantage of the growing availability of parallel platforms to speed up regression, a key component of our CRF learning methods. Our Shotgun algorithm for parallel regression can achieve near-linear speedups, and extensive experiments show it to be one of the fastest methods for sparse regression.
Impact of the turnover in the high-z galaxy luminosity function on the 21-cm signal during Cosmic Dawn and Epoch of Reionization
Creators: name: Zhang, Zekang
name: Shan, Huanyuan
name: Gu, Junhua
name: Zheng, Qian
name: Xu, Yidong
name: Yue, Bin
name: Liu, Yuchen
name: Zhu, Zhenghao
name: Guo, Quan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The shape of the faint-end of the high-z galaxy luminosity function (LF) informs early star formation and reionization physics during the Cosmic Dawn and Epoch of Reionization. Until recently, based on the strong gravitational lensing cluster deep surveys, the Hubble Frontier Fields (HFF) has found a potential turnover in the ultraviolet (UV) LF at z$\sim$6. In this paper, we analyze the contribution of extremely faint galaxies with the magnitude larger than the turnover magnitude in LF to cosmic reionization. We apply the measurement from HFF to our suppressed star formation efficiency model, including three free parameters: halo mass threshold $M_t$, curvature parameter $β$ and a UV conversion factor $l_{\rm UV}$. According to our fit of 68\% confidence level, the high-redshift star formation in haloes smaller than $ M_t=1.82^{+2.86}_{-1.08}\times10^{10} \rm M_{\odot}$ is found to be dampened. The turnover magnitude $\rm \gtrsim -13.99-2.45$, correspondingly the halo mass $\lesssim(4.57+20.03)\times10^{9} \rm M_{\odot}$. We find that the absorption trough in the global 21-cm signal is sensitive to our SFE model parameters. Together with ($β$, $l_{\rm UV}$) = ($2.17^{+2.42}_{-1.72}$, $9.33^{+0.43}_{-0.42} \rm ~erg~yr ~s^{-1}M_{\odot}^{-1})$, the trough locates at $\sim$ $134^{+10}_{-17}$ $\rm MHz$ with an amplitude of $\sim$ $-237^{-6}_{+7}$ $\rm mK$, compared to (106\rm MHz, -212\rm mK) in the absence of turnover. Besides, we find that the star formation of faint galaxies has also an impact on the 21-cm power spectra. The best fitting peak power decreases by $\sim4\%$ and shifts towards smaller scales from $0.88 h \rm Mpc^{-1}$ to $0.91 h \rm Mpc^{-1}$. According to our calculation, such impact is distinguishable with the forthcoming Square Kilometre Array.
description: 11 pages, 5 figures; Accepted by MNRAS
Can Decoherence Solve the Measurement Problem?
Creators: name: Bhaumik, Mani L.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Popular Physics (physics.pop-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The quantum decoherence program has become more attractive in providing an acceptable solution for the long-standing quantum measurement problem. Decoherence by quantum entanglement happens very quickly to entangle the quantum system with the environment including the detector. But in the final stage of measurement, acquiring the unentangled pointer states poses some problems. Recent experimental observations of the effect of the ubiquitous quantum vacuum fluctuations in destroying quantum entanglement appears to provide a solution.
description: 9 pages
Stellar Populations of Lyman-alpha Emitting Galaxies in the HETDEX Survey I: An Analysis of LAEs in the GOODS-N Field
Creators: name: McCarron, Adam P.
name: Finkelstein, Steven L.
name: Ortiz, Oscar A. Chavez
name: Davis, Dustin
name: Cooper, Erin Mentuch
name: Jung, Intae
name: White, Delaney R.
name: Leung, Gene C. K.
name: Gebhardt, Karl
name: Acquaviva, Viviana
name: Bowman, William P.
name: Ciardullo, Robin
name: Gawiser, Eric
name: Gronwall, Caryl
name: Hill, Gary J.
name: Kollatschny, Wolfram
name: Landriau, Martin
name: Liu, Chenxu
name: Mock, Daniel N.
name: Sanchez, Ariel G.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present the results of a stellar-population analysis of Lyman-alpha emitting galaxies (LAES) in GOODS-N at 1.9 < z < 3.5 spectroscopically identified by the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). We provide a method for connecting emission-line detections from the blind spectroscopic survey to imaging counterparts, a crucial tool needed as HETDEX builds a massive database of ~1 million Lyman-alpha detections. Using photometric data spanning as many as 11 filters covering 0.4-4.5 microns from the Hubble and Spitzer Space Telescopes, we study the objects' global properties and explore which properties impact the strength of Lyman-alpha emission. We measure a median stellar mass of 0.8 (^+2.9_-0.5) x 10^9 Msol and conclude that the physical properties of HETDEX spectroscopically-selected LAEs are comparable to LAEs selected by previous deep narrow band studies. We find that stellar mass and star formation rate correlate strongly with the Lyman-alpha equivalent width. We then use a known sample of z>7 LAEs to perform a proto-study of predicting Lyman-alpha emission from galaxies in the Epoch of Reionization, finding agreement at the 1-sigma level between prediction and observation for the majority of strong emitters.
description: 29 pages, 22 figures, Accepted to the Astrophysical Journal
Ανάπτυξη στρατηγικού μάνατζμεντ και απόκτηση ανταγωνιστικού πλεονεκτήματος - Μελέτη περίπτωσης
Creators: name: Στεφάνου, Γεωργία
Publisher: name: Πανεπιστήμιο Πειραιώς
Year: 2023
Subjects: subject: Στρατηγικό μάνατζμεντ
subject: Στρατηγική
subject: Διαμόρφωση στρατηγικής
subject: Υλοποίηση στρατηγικής
subject: Ανταγωνιστικό πλεονέκτημα

description: Σκοπός της συγκεκριμένης διπλωματικής είναι να διερευνηθούν οι βασικές αρχές του στρατηγικού μάνατζμεντ σε σχέση με τη διαμόρφωση ανταγωνιστικού πλεονεκτήματος, τί στρατηγική δηλαδή θα πρέπει να διαμορφώσει ο εκάστοτε οργανισμός, ώστε να καταφέρει να προσαρμόζεται στις συνεχείς μεταβολές του περιβάλλοντος και παράλληλα να δημιουργεί ικανοποιημένους πελάτες. Για τις ανάγκες της ανάλυσης, η εργασία διαιρέθηκε σε τρία κεφάλαια. Στο πρώτο κεφάλαιο παρουσιάζονται λεπτομερώς, οι βασικές αρχές του στρατηγικού μάνατζμεντ, αναλύεται η έννοια και η σημασία της στρατηγικής και στη συνέχεια η έννοια του στρατηγικού μάνατζμεντ και η σημασία της παρουσίας του μέσα σε μία επιχείρηση. Επίσης, γίνεται διάκριση του περιβάλλοντος σε εσωτερικό και εξωτερικό με αναλυτική προσέγγιση αυτών, ώστε να φανεί η αναγκαιότητα του στρατηγικού μάνατζμεντ για τη διαμόρφωση, υλοποίηση, αξιολόγηση και έλεγχο στρατηγικής. Στο δεύτερο κεφάλαιο, αναπτύσσεται η έννοια του ανταγωνιστικού πλεονεκτήματος, τι είναι, πώς διακρίνεται και ποια η σημασία του για μία επιχείρηση. Αναφέρονται αναλυτικά οι πηγές προέλευσής του αλλά και η ανάγκη για τη διαμόρφωση ενός διατηρήσιμου ανταγωνιστικού πλεονεκτήματος, πώς δηλαδή μία επιχείρηση θα καταφέρει να μετατρέψει το πλεονέκτημά της, σε διατηρήσιμο ανταγωνιστικό πλεονέκτημα με τη συνεχή αναζωογόνησή του, με σκοπό τη δημιουργία ικανοποιημένων πελατών. Τέλος, στο συγκεκριμένο κεφάλαιο, αναφέρονται οι στρατηγικές ανάπτυξης του ανταγωνιστικού πλεονεκτήματος ενός οργανισμού με τη βοήθεια των δυνάμεών του, διακρίνοντας τες σε ηγεσία κόστους, διαφοροποίηση και εστίαση. Στο τρίτο και τελευταίο κεφάλαιο, παρουσιάζεται μία μελέτη περίπτωσης μίας μικρομεσαίας επιχείρησης που ανήκει στον κλάδο του χονδρικού εμπορίου των ανταλλακτικών φίλτρων. Δίνονται, αρχικά, λεπτομέρειες για την επιχείρηση, τον κλάδο που ανήκει, τα βασικά της στοιχεία, το όραμα, την αποστολή της, το μέγεθός της, τα τμήματα και τους εργαζομένους της και άλλα. Στη συνέχεια, αναλύεται το εσωτερικό και εξωτερικό της περιβάλλον, οι δυνάμεις, οι αδυναμίες, οι ευκαιρίες και οι απειλές που διαθέτει αλλά και στρατηγικές που ακολουθεί. Δίνονται λεπτομέρειες για το πώς δηλαδή καταφέρνει να στέκεται απέναντι στις μεταβολές του περιβάλλοντος, ποια επιχειρηματική και επιχειρησιακή πολιτική ακολουθεί και πώς αναπτύσσει και διατηρεί το ανταγωνιστικό της πλεονέκτημα και ως επακόλουθο ευχαριστημένους πελάτες. Τέλος, η εργασία τελειώνει με μία πρόταση στρατηγικής, ώστε να καταφέρει η επιχείρηση να βελτιωθεί στο μέλλον.
SDSS-IV MaNGA: The MaNGA Dwarf Galaxy Sample
Creators: name: Cano-Díaz, M.
name: Hernández-Toledo, H. M.
name: Rodríguez-Puebla, A.
name: Ibarra-Medel, H. J.
name: Ávila-Reese, V.
name: Valenzuela, O.
name: Medellin-Hurtado, A. E.
name: Vázquez-Mata, J. A.
name: Weijmans, A.
name: González, J. J.
name: Aquino-Ortiz, E.
name: Martínez-Vázquez, L. A.
name: Lane, Richard R.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present the MaNGA Dwarf galaxy, MaNDala, Value-Added-Catalog, VAC, from the final release of the Sloan Digital Sky Survey-IV program. MaNDala consists of 136 randomly selected bright dwarf galaxies with $M_{*}<10^{9.1}\odot$ and $M_{g}>-18.5$ making it the largest Integral Field Spectroscopy homogeneous sample of dwarf galaxies. We release a photometric analysis of the $g,r$ and $z$ broadband imaging based on the DESI Legacy Imaging Surveys as well as the spectroscopic analysis based on the Pipe3D SDSS-IV VAC. Our release includes the surface brightness (SB), geometric parameters and color profiles, Sérsic fits as well as stellar population properties (such as, stellar ages, metallicities, star formation histories), and emission lines fluxes within the FOV and the effective radii of the galaxies. We find that the majority of the MaNDala galaxies are star forming late-type galaxies with $\langle{}n_{\text{Sersic,r}}\rangle\sim1.6$ that are centrals (central/satellite dichotomy). MaNDala covers a large range of SB values (we find 11 candidates of ultra diffuse galaxies and 3 compact ones), filling the gap between classical dwarfs and low-mass galaxies in the Kormendy Diagram and in the size-mass/luminosity relation, whichseems to flatten at $10^82$, while the last $20\%$ was at $\langle{}z\rangle<0.3$. Finally, a bending of the sSFR-$M_{*}$ relation at $M_{*}\sim10^{9}\odot$ for the main sequence galaxies seems to be supported by MaNDala.
description: 29 pages, 17 figures. Accepted to appear in The Astronomical Journal
Chandra Identification of Two AGN Discovered by INTEGRAL
Creators: name: Tomsick, John A.
name: Krivonos, Roman
name: Rahoui, Farid
name: Ajello, Marco
name: Rodriguez, Jerome
name: Barriere, Nicolas
name: Bodaghee, Arash
name: Chaty, Sylvain
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Here, we report on observations of two hard X-ray sources that were originally discovered with the INTEGRAL satellite: IGR J04059+5416 and IGR J08297-4250. We use the Chandra X-ray Observatory to localize the sources and then archival near-IR images to identify the counterparts. Both sources have counterparts in the catalog of extended 2 Micron All-Sky Survey sources, and the counterpart to IGR J04059+5416 has been previously identified as a galaxy. Thus, we place IGR J04059+5416 in the class of Active Galactic Nuclei (AGN), and we suggest that IGR J08297-4250 is also an AGN. If this identification is correct, the near-IR images suggest that the host galaxy of IGR J08297-4250 may be merging with a smaller nearby galaxy. For IGR J04059+5416, the 0.3-86 keV spectrum from Chandra and INTEGRAL is consistent with an absorbed power-law with a column density of N_H = 3.1(+2.0)(-1.5)e22 cm-2 and a photon index of Gamma = 1.4+/-0.7, and we suggest that it is a Seyfert galaxy. For IGR J08297-4250, the photon index is similar, Gamma = 1.5+/-0.8, but the source is highly absorbed (N_H = 6.1(+10.1)(-4.3)e23 cm-2).
description: 10 pages, 5 figures, 5 tables
Fluctuation dynamics in a relativistic fluid with a critical point
Creators: name: Stephanov, M.
name: Yee, H.-U.
name: An, X.
name: Başar, G.
Publisher: name: American Physical Society
Year: 2020

description: To describe dynamics of bulk and fluctuations near the QCD critical point we develop general relativistic fluctuation formalism for a fluid carrying baryon charge. Feedback of fluctuations modifies hydrodynamic coefficients including bulk viscosity and conductivity and introduces nonlocal and noninstantaneous terms in constitutive equations. We perform necessary ultraviolet (short-distance) renormalization to obtain cutoff-independent deterministic equations suitable for numerical implementation. We use the equations to calculate the universal nonanalytic small-frequency dependence of transport coefficients due to fluctuations (long-time tails). Focusing on the critical mode we show how this general formalism matches existing Hydro+ description of fluctuations near the QCD critical point and nontrivially extends it inside and outside of the critical region.
AMS :: ATX August 2021 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: The University of Texas at Austin
Year: 2021
Subjects: American Studies
Twitter

description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
Searching for cataclysmic variable stars in unidentified X-ray sources
Creators: name: Takata, J.
name: Wang, X. F.
name: Kong, A. K. H.
name: Mao, J.
name: Hou, X.
name: Hu, C. -P.
name: Lin, L. C. -C.
name: Li, K. L.
name: Hui, C. Y.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We carry out a photometric search for new cataclysmic variable stars (CVs), with the goal of identification for candidates of AR~Scorpii-type binary systems. We select GAIA sources that are likely associated with unidentified X-ray sources, and analyze the light curves taken by the Zwicky Transient Facility, Transiting Exoplanet Survey Satellite, and Lulin One-meter Telescope in Taiwan. We investigate eight sources as candidates for CVs, among which six sources are new identifications. Another two sources have been recognized as CVs in previous studies, but no detailed investigations have been done. We identify two eclipsing systems that are associated with an unidentified XMM-Newton or Swift source, and one promising candidate for polar associated with an unidentified ASKA source. Two polar candidates may locate in the so-called period gap of a CV, and the other six candidates have an orbital period shorter than that of the period gap. Although we do not identify a promising candidate for AR~Scorpii-type binary systems, our study suggests that CV systems that have X-ray emission and do not show frequent outbursts may have been missed in previous surveys.
description: 21 pages, 24 figures, accepted for publication in ApJ. "Note added in proof" and "Appendix C" are added in the revised version
Lattice-switch Monte Carlo: the fcc-bcc problem
Creators: name: Underwood, T. L.
name: Ackland, G. J.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Lattice-switch Monte Carlo is an efficient method for calculating the free energy difference between two solid phases, or a solid and a fluid phase. Here, we provide a brief introduction to the method, and list its applications since its inception. We then describe a lattice switch for the fcc and bcc phases based on the Bain orientation relationship. Finally, we present preliminary results regarding our application of the method to the fcc and bcc phases in the Lennard-Jones system. Our initial calculations reveal that the bcc phase is unstable, quickly degenerating into some as yet undetermined metastable solid phase. This renders conventional lattice-switch Monte Carlo intractable for this phase. Possible solutions to this problem are discussed.
Improving Device Driver Reliability through Decoupled Dynamic Binary Analyses
Creators: name: Olatunji O. Ruwase
Publisher: name: Figshare
Year: 2018
Subjects: subject: 89999 Information and Computing Sciences not elsewhere classified
subject: FOS: Computer and information sciences

description: Device drivers are Operating Systems (OS) extensions that enable the use of I/O devices in computing systems. However, studies have identified drivers as an Achilles’ heel of system reliability, their high fault rate accounting for a significant portion of system failures. Consequently, significant effort has been directed towards improving system robustness by protecting system components (e.g., OS kernel, I/O devices, etc.) from the harmful effects of driver faults. In contrast to prior techniques which focused on preventing unsafe driver interactions (e.g., with the OS kernel), my thesis is that checking a driver’s execution for correctness violations results in the detection and mitigation of more faults.
To validate this thesis, I present Guardrail, a flexible and powerful framework that enables instruction-grained dynamic analysis (e.g., data race detection) of unmodified kernel-mode driver binaries to safeguard I/O operations and devices from driver faults. Guardrail decouples the analysis tool from driver execution to improve performance, and runs it in user-space to simplify the deployment of new tools. Moreover, Guardrail leverages virtualization to be transparent to both the driver and device, and enable support for arbitrary driver/device combinations.
To demonstrate Guardrail’s generality, I implemented three novel dynamic checking tools within the framework for detecting memory faults, data races and DMA faults in drivers. These tools found 25 serious bugs, including previously unknown bugs, in Linux storage and network drivers. Some of the bugs existed in several Linux (and driver) releases, suggesting their elusiveness to existing approaches. Guardrail easily detected these bugs using common driver workloads.
Finally, I present an evaluation of using Guardrail to protect network and storage I/O operations from memory faults, data races and DMA faults in drivers. The results show that with hardware-assisted logging for decoupling the heavyweight analyses from driver execution, standard I/O workloads generally experienced negligible slowdown on their end-to-end performance.
In conclusion, Guardrail’s high fidelity fault detection and efficient monitoring performance makes it a promising approach for improving the resilience of computing systems to the wide variety of driver faults.
Assessment of creditworthiness models privacy-preserving training with synthetic data
Creators: name: Muñoz-Cancino, Ricardo
name: Bravo, Cristián
name: Ríos, Sebastián A.
name: Graña, Manuel
Publisher: name: arXiv
Year: 2023
Subjects: subject: Risk Management (q-fin.RM)
subject: Machine Learning (cs.LG)
subject: Social and Information Networks (cs.SI)
subject: FOS: Economics and business
subject: FOS: Computer and information sciences

description: Credit scoring models are the primary instrument used by financial institutions to manage credit risk. The scarcity of research on behavioral scoring is due to the difficult data access. Financial institutions have to maintain the privacy and security of borrowers' information refrain them from collaborating in research initiatives. In this work, we present a methodology that allows us to evaluate the performance of models trained with synthetic data when they are applied to real-world data. Our results show that synthetic data quality is increasingly poor when the number of attributes increases. However, creditworthiness assessment models trained with synthetic data show a reduction of 3\% of AUC and 6\% of KS when compared with models trained with real data. These results have a significant impact since they encourage credit risk investigation from synthetic data, making it possible to maintain borrowers' privacy and to address problems that until now have been hampered by the availability of information.
Effect of Protonation and Deprotonation on Electron Transfer Mediated Decay and Interatomic Coulombic Decay
Creators: name: Kumar, Ravi
name: Vaval, Dr. Nayana
Publisher: name: arXiv
Year: 2022
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Electronically excited atoms or molecules in an environment are often subject to interatomic/intermolecular Coulombic decay (ICD) and/or electron transfer mediated decay (ETMD) mechanisms. A few of the numerous variables that can impact these non-radiative decay mechanisms include bond distance, the number of nearby atoms or molecules, and the polarisation effect. In this paper, we have studied the effect of protonation and deprotonation on the ionization potential (IP), double ionization potential (DIP), and lifetime (or decay width) of the temporary bound state in these non-radiative decay processes. We have chosen LiH-NH$_3$ and LiH-H$_2$O as test systems. The equation of motion coupled cluster singles and doubles method augmented by complex absorbing potential (CAP-EOM-CCSD) has been used in calculating the energetic position of the decaying state and the system's decay rate. Deprotonation of LiH-NH$_3$/LiH-H$_2$O either from the metal center (LiH) or from ammonia/water lowers the IP and DIP compared to the neutral systems. In contrast, protonation increases these quantities compared to neutral systems. The protonation closes the inner valence state relaxation channels for ICD/ETMD. For example, the decay of the O-2s/N-2s state stops in protonated systems (LiH$_2^+$-H$_2$O, LiH$_2^+$-NH$_3$, and LiH-NH$_4^+$). Our study also shows that the efficiency, i.e., the rate of ICD/ETMD, can be altered by protonation and deprotonation. It is expected to have implications for chemical and biological systems
description: 8 pages, 6 figures, 2 table (including TOC)
Models of Goldstone Gauginos
Creators: name: Alves, Daniele S. M.
name: Galloway, Jamison
name: McCullough, Matthew
name: Weiner, Neal
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Models with Dirac gauginos provide appealing scenarios for physics beyond the standard model. They have smaller radiative corrections to the Higgs mass, a suppression of certain SUSY production processes, and ameliorated flavor constraints. Unfortunately, they also generally have tachyons, the solutions to which typically spoil these positive features. The recently proposed "Goldstone Gaugino" mechanism provides a simple solution that eliminates these tachyonic states. We provide details on this mechanism and explore models for its origin. In particular, we find SUSY QCD models that realize this idea simply, and discuss scenarios for unification.
description: 33 pages, 4 figures
AMS :: ATX October 2021 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: The University of Texas at Austin
Year: 2021
Subjects: American Studies
Twitter

description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
The legacy of ADM
Creators: name: Deser, S.
Publisher: name: arXiv
Year: 2015
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: History and Philosophy of Physics (physics.hist-ph)
subject: FOS: Physical sciences

description: This tribute to the memory of my old friend and collaborator, Richard Arnowitt, focuses on the history, results and physical significance of the Arnowitt-Deser-Misner formulation of General Relativity, starting from its birth in 1958-9 through its completion, in a series of over a dozen papers, in 1962-3. A few of its later applications are also reviewed.
description: Invited paper for a special issue of Physica Scripta on ADM and SUGRA, in memoriam Richard Arnowitt. Replacement is published version
AMS :: ATX February 2022 Blog Archive
Creators: name: Department Of American Studies
Publisher: name: The University of Texas at Austin
Year: 2022
Subjects: American Studies
Twitter

description: @AmStudies is a Twitter feed dedicated to representing the many activities and interests of the department of American Studies at The University of Texas at Austin. Together with the department’s blog, this feed exists to serve the AMS and Austin communities by acting as a hub for up-to-date information on events and opportunities at UT and beyond.
Large-Scale Simulations of Hydrogen and Helium Reionization
Creators: name: Plante, Paul La
Publisher: name: Figshare
Year: 2018
Subjects: subject: 20399 Classical Physics not elsewhere classified
subject: FOS: Physical sciences

description: I present here discussion and results of large-scale simulations of cosmic reionization, both hydrogen and helium. For hydrogen reionization, I have focused on the impact that the light cone effect has on observables related to the 21 cm hyperfine signal, with specific attention given to how the duration of reionization affects the results. I show that the light cone effect can introduce significant anisotropy in the detected signal, especially for (cosmically) brief reionization scenarios. Following this, I discuss a series of simulations of helium reionization, focusing this time on observables related to the Lyman-  forest. First I present a method by which dark matter halos from simulations can be populated with quasars to match the latest quasar luminosity function and clustering measurements. Then I discuss a suite of simulations of helium reionization where the quasar model is modified to explore the impact on the timing and duration of reionization, as well as related measurements of the Lyman-  forest. I show that many of the statistical features from the H i Lyman-  forest are similar once the global optical depth is the same across simulations. However, differences of up to a factor of two remain, which might facilitate detection in the future. Finally, I show that differences in the He ii Lyman-  forest are significant, and provide a promising way forward for determining the helium reionization history of the Universe.
Relativistic hydrodynamic fluctuations
Creators: name: An, X.
name: Yee, H.-U.
name: Stephanov, M.
name: Başar, G.
Publisher: name: American Physical Society
Year: 2019

description: We present a general systematic formalism for describing dynamics of fluctuations in an arbitrary relativistic hydrodynamic flow, including their feedback (known as long-time hydrodynamic tails). The fluctuations are described by two-point equal-time correlation functions. We introduce a definition of equal time in a situation where the local rest frame is determined by the local flow velocity and a method of taking derivatives and Wigner transforms of such equal-time correlation functions, which we call confluent. We find that not only do the equations for confluent Wigner functions resemble kinetic equations but also the kinetic equation for phonons propagating on an arbitrary background nontrivially matches the equations for Wigner functions, including relativistic inertial and Coriolis forces due to acceleration and vorticity of the flow. We also describe the procedure of renormalization of short-distance singularities which eliminates cutoff dependence, allowing efficient numerical implementation of these equations.
title: Μελέτη και αξιολόγηση γηγενών στελεχών Saccharomyces cerevisiae
title: Study and evaluation of indigenous Saccharomyces cerevisiae species
titleType: AlternativeTitle
Creators: name: Παπαχρήστου, Γεώργιος
name: Γράμψας, Αθανάσιος
Publisher: name: Πανεπιστήμιο Δυτικής Αττικής
Year: 2023
Subjects: Ασύρτικο
Saccharomyces cerevisiae
Κινητική ζυμώσεων
Αρωματικό προφίλ
Αλκοολική ζύμωση
Γηγενείς ζύμες

description: Η παρούσα πτυχιακή εργασία επικεντρώνεται στην αξιολόγηση γηγενών στελεχών του είδους Saccharomyces cerevisiae, ως προς το οινολογικό τους δυναμικό για την παραγωγή οίνων της ποικιλίας Ασύρτικο. Οι εξεταζόμενες ζύμες έχουν απομονωθεί από αυθόρμητες ζυμώσεις διαφορετικών περιοχών και ποικιλιών. Αρχικά τα 20 στελέχη αξιολογήθηκαν μέσω μικρό-οινοποιήσεων εργαστηριακής κλίμακας σε παστεριωμένο γλεύκος Ασύρτικου, ως προς την ζυμωτική τους ικανότητα και τον αρωματικό τους χαρακτήρα. Στην συνέχεια, επιλέχθηκαν τα στελέχη με το μεγαλύτερο οινολογικό ενδιαφέρον και εμβολιάστηκαν εκ νέου σε ζυμώσεις μεγαλύτερης εργαστηριακής κλίμακας σε παστεριωμένο γλεύκος της ποικιλίας Ασύρτικο. Στις ζυμώσεις αυτές, αξιολογήθηκε η ζυμωτική ικανότητα των στελεχών, τα οργανοληπτικά χαρακτηριστικά των παραγόμενων οίνων και πραγματοποιήθηκαν και χημικές αναλύσεις των δειγμάτων, σύμφωνα με τα επίσημα πρωτόκολλα του OIV, πριν και μετά την αλκοολική ζύμωση. Πιο συγκεκριμένα, οι αναλύσεις των οίνων αφορούσαν την ολική οξύτητα, το παραγόμενο διοξείδιο του θείου (SO2) στην ελεύθερη και ολική μορφή του, το pH, το αφομοιώσιμο άζωτο, την παραγωγή οξικού οξέος και την περιεκτικότητα σε αιθανόλη. Τέλος μετά την ανάλυση των αποτελεσμάτων και τη στατιστική επεξεργασία αυτών, πραγματοποιήθηκε επιλογή του στελέχους που απέδωσε βέλτιστα στα ζητούμενα του πειράματος.
Low-$J$ transitions in $\tilde{A}^2Π(0,0,0)-\tilde{X}^2Σ^+(0,0,0)$ band of buffer-gas-cooled CaOH
Creators: name: Takahashi, Yuiki
name: Baba, Masaaki
name: Enomoto, Katsunari
name: Hiramoto, Ayami
name: Iwakuni, Kana
name: Kuma, Susumu
name: Tobaru, Reo
name: Miyamoto, Yuki
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Calcium monohydroxide radical (CaOH) is receiving an increasing amount of attention from the astrophysics community as it is expected to be present in the atmospheres of hot rocky super-Earth exoplanets as well as interstellar and circumstellar environments. Here, we report the high-resolution laboratory absorption spectroscopy on low-$J$ transitions in $\tilde{A}^2Π(0,0,0)-\tilde{X}^2Σ^+(0,0,0)$ band of buffer-gas-cooled CaOH. In total, 40 transitions out of the low-$J$ states were assigned, including 27 transitions which have not been reported in previous literature. The determined rotational constants for both ground and excited states are in excellent agreement with previous literature, and the measurement uncertainty for the absolute transition frequencies was improved by more than a factor of three. This will aid future interstellar, circumstellar, and atmospheric identifications of CaOH. The buffer-gas-cooling method employed here is a particularly powerful method to probe low-$J$ transitions and is easily applicable to other astrophysical molecules.
Finite density QED1+1 near Lefschetz thimbles
Creators: name: Alexandru, A.
name: Lawrence, S.
name: Başar, G.
name: Lamm, H.
name: Bedaque, P.F.
Publisher: name: American Physical Society
Year: 2018

description: One strategy for reducing the sign problem in finite-density field theories is to deform the path integral contour from real to complex fields. If the deformed manifold is the appropriate combination of Lefschetz thimbles - or somewhat close to them - the sign problem is alleviated. Gauge theories require generalizing the definition of thimble decompositions, and therefore it is unclear how to carry out a generalized thimble method. In this paper we discuss some of the conceptual issues involved by applying this method to QED1+1 at finite density, showing that the generalized thimble method yields correct results with less computational effort than standard methods.
WR 63: A multiple system (O+O)+WR ?
Creators: name: Chené, A. -N.
name: Mahy, L.
name: Gosset, E.
name: St-Louis, N.
name: Dsilva, K.
name: Manick, R.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The spectrum of the Wolf-Rayet (WR) star WR 63 contains spectral lines of two different O stars that show regular radial velocity (RV) variations with amplitudes of ~160 and ~225 km/s on a ~4.03 d period. The light-curve shows two narrow eclipses that are 0.2 mag deep on the same period as the RV changes. On the other hand, our data show no significant RV variations for the WR spectral lines. Those findings are compatible with WR 63 being a triple system composed of two non-interacting late O stars orbiting a WR star on a period larger than 1000 days. The amplitude of the WR spectral line-profile variability reaches 7-8% of the line intensity and seems related to a 0.04 mag periodic photometric variation. Large wind density structures are a possible origin of this variability, but our data are not sufficient to verify this. Our analysis shows that, should the three stars be bound, they would be coeval with an age of about 5.9+/-1.4 Myrs. The distance to the O stars is estimated to be 3.4+/-0.5 kpc. Their dynamical masses are 14.3+/-0.1 and 10.3+/-0.1 M_sol. Using rotating, single star evolutionary tracks, we estimate their initial masses to be 18+/-2 and 16+/-2 M_sol for the primary and the secondary, respectively. Regular spectral monitoring is required in the future to detect RV variations of the WR star that would prove that it is gravitationally bound to the close O+OB system and to determine its mass.
description: 11 pages, 9 figures, 2 tables
D6.5 - Evaluation and Validation Report
Creators: name: Maqueda, Erik
Publisher: name: Zenodo
Year: 2023
Subjects: Validation
KPIs
Impact assessment
Large Scale Pilots
Use cases

description: This report summarises the preliminary validation results of the different components developed in WP2, WP3 and WP4 for all the pilots and corresponding use cases. The validation is performed based on the KPIs identified in the validation plan as per explained in deliverable D6.6. This report is the first version of the validation report and might not be fully complete. The main objective of this first version is to be an initial touchpoint to understand the current status of the validation of the different pilots, identify potential risk and put a contingency plan towards the final complete version that will be submitted in the end of the project (M36).
Do Cellular Automaton Avalanche Models Simulate the Quasi-Periodic Pulsations of Solar Flares?
Creators: name: Farhang, Nastaran
name: Shahbazi, Farhad
name: Safari, Hossein
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Quasi-periodic pulsations (QPPs) with various periods that originate in the underlying magnetohydrodynamic processes of the flaring structures are detected repeatedly in the solar flare emissions. We apply a 2D cellular automaton (CA) avalanche model to simulate QPPs as a result of a repetitive load/unload mechanism. We show that the frequent occurrence of magnetic reconnections in a flaring loop could induce quasi-periodic patterns in the detected emissions. We obtain that among 21070 simulated flares, 813 events endure over 50 seconds, scaled with the temporal resolution of the Yohkoh Hard X-ray Telescope, and about 70 percent of these rather long-lasting events exhibit QPPs. We also illustrate that the applied CA model provides a wide range of periodicities for QPPs. Furthermore, we observe the presence of multiple periods in nearly 50 percent of the cases applying the Lomb-Scargle periodogram. A lognormal distribution is fitted to the unimodal distribution of the periods as a manifestation of an underlying multiplicative mechanism that typifies the effect of the system's independent varying parameters. The global maximum of the periods' lognormal distribution is located at 29.29 seconds. We compare statistics of the simulated QPPs with parameters of the host flares and discuss the impacts of flare properties on QPPs' periods. Considering the intrinsic characteristic of CA models, namely the repetitive load/unload mechanism, and the obtained pieces of evidence, we suggest that CA models may generate QPPs. We also examine the applicability of the autoregressive integrated moving average models to describe the simulated and observational QPPs.
Tempered transitions between thimbles
Creators: name: Bedaque, P.F.
name: Alexandru, A.
name: Warrington, N.C.
name: Başar, G.
Publisher: name: American Physical Society
Year: 2017

description: Quantum field theories with complex actions cannot be investigated using importance sampling due to the sign problem. One possible solution is to use the holomorphic gradient flow, a method we introduced related to the Lefschetz thimbles idea. In many cases the probability distribution generated by this method is multimodal and standard Monte Carlo sampling fails. We propose an algorithm that incorporates tempered proposals to solve this problem. We apply this algorithm to the Thirring 0+1-dimensional model at finite density for a parameter set where standard sampling fails and show that tempered proposals cure this problem.