cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
A real-time 3D motion tracking system
Creators: name: Kam, Johnny
Publisher: name: University of British Columbia
Year: 2008

description: Vision allows one to react to rapid changes in the surrounding environment. The ability of animals to control their eye movements and follow a moving target has always been a focus in biological research. The biological control system that governs the eye movements is known as the oculo motor control system. Generally, the control of eye movements to follow a moving visual target is known as gaze control. The primary goal of motion tracking is to keep an object of interest, generally known as the visual target, in the view of the observer at all time. Tracking can be driven by changes perceived from the real world. One obvious change introduced by a moving object is the change in its location, which can be described in terms of displacement. In this project, we will show that by using stereo disparity and optical flow, two significant types of displacements, as the major source of directing signals in a robotic gaze control system, we can determine where the moving object is located and perform the tracking duty, without recognizing what the object is. The recent advances in computer hardware, exemplified by our Datacube MaxVideo 200 system and a network of Transputers, make it possible to perform image processing operations at video rates, and to implement real-time systems with input images obtained from video cameras. The main purposes of this project are to establish some simple control theories to monitor changes perceived in the real world, and to apply such theories in the implementation of a real-time three-dimensional motion tracking system on a binocular camera head system installed in the Laboratory for Computational Intelligence(LCI) at the Department of Computer Science of the University of British Columbia(UBC). The control scheme of our motion tracking system is based on the Perception-Reasoning-Action (PRA) regime. We will describe an approach of using an active monitoring process together with a process for accumulating temporal data to allow different hardware components running at different rates to communicate and cooperate in a real-time system working on real world data. We will also describe a cancellation method to reduce the unstable effects of background optical flow generated from ego-motion, and create a "pop-out" effect in the motion field to ease the burden of target selection. The results of various experiments conducted, and the difficulties of tracking without any knowledge of the world and the objects will also be discussed.
Exploring marine compounds as potential biocontrol agents against powdery mildew for agricultural sustainability: a computer-based approach
Creators: name: Sudhakaran, Gokul
name: Liu, Xinghui
name: Almutairi, Bader O.
name: Meivelu, Moovendhan
name: Sathishkumar, Kuppusamy
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: Biotechnology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Biological Sciences not elsewhere classified
subject: Plant Biology
subject: Virology

description: Powdery mildew is a pervasive fungal disease causing significant economic losses globally. Continuous use of synthetic fungicides has led to environmental concerns and resistant fungal strains. This study explores marine-derived cephalostatins from the South African Natural Compounds Database as novel fungicidal agents for managing powdery mildew. Using molecular docking techniques, we investigated the interaction between selected cephalostatins and critical proteins involved in powdery mildew pathogenesis. Compounds were selected based on drug-likeness and bioactivity, adhering to Lipinski’s Rule of Five. Molecular interactions, binding affinities, and stability were analysed using AutoDock Vina, PyMOL, and Discovery Studio. Cephalostatin 17 exhibited the highest binding affinity (−10.4 kcal/mol), indicating strong potential for inhibiting fungal growth through significant hydrogen bonding and hydrophobic interactions. The study’s primary limitation is the reliance on computational predictions, necessitating experimental validation. Cephalostatin 17 stands out as a promising candidate for sustainable agricultural practices.
Landau-Zener Tunnelling in a Nonlinear Three-level System
Creators: name: Wang, Guan-Fang
name: Ye, Di-Fa
name: Fu, Li-Bin
name: Chen, Xu-Zong
name: Liu, Jie
Publisher: name: arXiv
Year: 2006
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present a comprehensive analysis of the Landau-Zener tunnelling of a nonlinear three-level system in a linearly sweeping external field. We find the presence of nonzero tunnelling probability in the adiabatic limit (i.e., very slowly sweeping field) even for the situation that the nonlinear term is very small and the energy levels keep the same topological structure as that of linear case. In particular, the tunnelling is irregular with showing an unresolved sensitivity on the sweeping rate. For the case of fast-sweeping fields, we derive an analytic expression for the tunnelling probability with stationary phase approximation and show that the nonlinearity can dramatically influence the tunnelling probability when the nonlinear "internal field" resonate with the external field. We also discuss the asymmetry of the tunnelling probability induced by the nonlinearity. Physics behind the above phenomena is revealed and possible application of our model to triple-well trapped Bose-Einstein condensate is discussed.
description: 8 pages, 8 figures
Spacing statistics in two-mode random lasing
Creators: name: Zaitsev, Oleg
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Chaotic Dynamics (nlin.CD)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The distribution of spacings between the lasing frequencies for an ensemble of random lasers in the two-mode regime was computed. The random lasers are implemented as open chaotic cavities filled with an active medium. The spectral properties of the passive cavities are modeled with non-Hermitian random matrices. The spacing distribution is found to depend on the relation between the gain-profile width and the mean spacing of the passive-cavity modes. The distribution displays mode repulsion and, under certain conditions, agrees with the Wigner surmise. The role of mode competition is discussed.
description: 5 pages (v2: substantial changes, published version)
AGB interlopers in YSO catalogues hunted out by NEOWISE
Creators: name: Lee, Jeong-Eun
name: Lee, Sieun
name: Lee, Seonjae
name: Suh, Kyung-Won
name: Cho, Se-Hyung
name: Byun, Do-Young
name: Park, Wooseok
name: Herczeg, Gregory
name: Peña, Carlos Contreras
name: Johnstone, Doug
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: AGBs and YSOs often share the same domains in IR color-magnitude or color-color diagrams leading to potential mis-classification. We extracted a list of AGB interlopers from the published YSO catalogues using the periodogram analysis on NEOWISE time series data. YSO IR variability is typically stochastic and linked to episodic mass accretion. Furthermore, most variable YSOs are at an early evolutionary stage, with significant surrounding envelope and/or disk material. In contrast, AGBs are often identified by a well defined sinusoidal variability with periods of a few hundreds days. From our periodogram analysis of all known low mass YSOs in the Gould Belt, we find 85 AGB candidates, out of which 62 were previously classified as late-stage Class III YSOs. Most of these new AGB candidates have similar IR colors to O-rich AGBs. We observed 73 of these AGB candidates in the H2O, CH3OH and SiO maser lines to further reveal their nature. The SiO maser emission was detected in 10 sources, confirming them as AGBs since low mass YSOs, especially Class III YSOs, do not show such maser emission. The H2O and CH3OH maser lines were detected in none of our targets.
description: Accepted for publication in ApJL
Reliability analysis for mooring system of a spar in deepwater Gulf of Mexico
Creators: name: Dangayach, Sanyam
Publisher: name: The University of Texas at Austin
Year: 2004
Subjects: Mooring system
Gulf of Mexico
Floating production system

description: Reliability analysis for the mooring system of a floating production system has been undertaken for sea depths of 1000, 2000, and 3000 m. A methodology has been developed for the estimation of the distribution of extreme values of storm loads on the mooring system during a storm event due to the randomness of the storm event. Probability distribution of sea states in the Gulf of Mexico has been developed in terms of the met-ocean parameters. A relationship between storm severity and storm frequency has been established. A procedure has been developed for obtaining a probabilistic distribution of maximum load with regard to the uncertainty in the sea states in the design life. The uncertainty in the maximum load on the mooring lines due to uncertainty in the input parameters for the response model has been explored. The overall uncertainty in the maximum load on the mooring lines due to different sources has been evaluated. Using these results the component and system reliabilities of the mooring system have been quantified and the redundancy in the system analyzed.
Evaluation of the Project on the Development of Professional Qualified Teacher Using Coaching and Mentoring, Faculty of Naresuan University and the Secondary Educational Service Area Office 38 and 39 and Sukhothai Primary Educational Service Area Office 2
Creators: name: Wareerat Kaewurai
name: Teamjan Parnichprarinchai
name: Chaiwat Suttirat
name: Chalong Chatruprachewin
name: Amornrat Wattanatorn
name: Tipparat Sittiwong
Publisher: name: Graduate School;Nakhon Sawan Rajabhat University
Year: 2014
Subjects: project evaluation, professional qualified teacher, coaching and mentoring

description: 27, 9, SOCIAL SCIENCES RESEARCH AND ACADEMIC JOURNAL
Exploring self-consistency of the equations of axion electrodynamics in Weyl semimetals
Creators: name: Deng, Kuangyin
name: Van Dyke, John S.
name: Minic, Djordje
name: Heremans, J. J.
name: Barnes, Edwin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Recent works have provided evidence that an axial anomaly can arise in Weyl semimetals. If this is the case, then the electromagnetic response of Weyl semimetals should be governed by the equations of axion electrodynamics. These equations capture both the chiral magnetic and anomalous Hall effects in the limit of linear response, while at higher orders their solutions can provide detectable electromagnetic signatures of the anomaly. In this work, we consider three versions of axion electrodynamics that have been proposed in the Weyl semimetal literature. These versions differ in the form of the chiral magnetic term and in whether or not the axion is treated as a dynamical field. In each case, we look for solutions to these equations for simple sample geometries subject to applied external fields. We find that in the case of a linear chiral magnetic term generated by a non-dynamical axion, self-consistent solutions can generally be obtained. In this case, the magnetic field inside of the Weyl semimetal can be magnified significantly, providing a testable signature for experiments. Self-consistent solutions can also be obtained for dynamical axions, but only in cases where the chiral magnetic term vanishes identically. Finally, for a nonlinear form of the chiral magnetic term frequently considered in the literature, we find that there are no self-consistent solutions aside from a few special cases.
Transient Photo-response of Halide Perovskite on Optoelectronic Devices
Creators: name: Kim, So-Yeon
Publisher: name: Zenodo
Year: 2024

description: Abstract presented at the ' Perovskite and Organic Semiconductors for Next-Generation Photodetectors and Space Application (NextPDs) conference.

Accepted for an oral presentation by Kim, So-Yeon. presentation 026
Baryogenesis via Leptogenesis: Spontaneous B and L Violation
Creators: name: Perez, Pavel Fileviez
name: Murgui, Clara
name: Plascencia, Alexis D.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In order to address the baryon asymmetry in the Universe one needs to understand the origin of baryon (B) and lepton (L) number violation. In this article, we discuss the mechanism of baryogenesis via leptogenesis to explain the matter-antimatter asymmetry in theories with spontaneous breaking of baryon and lepton number. In this context, a lepton asymmetry is generated through the out-of-equilibrium decays of right-handed neutrinos at the high-scale, while local baryon number must be broken below the multi-TeV scale to satisfy the cosmological bounds on the dark matter relic density. We demonstrate how the lepton asymmetry generated via leptogenesis can be converted in two different ways: a) in the theory predicting Majorana dark matter the lepton asymmetry is converted into a baryon asymmetry, and b) in the theory with Dirac dark matter the decays of right-handed neutrinos can generate lepton and dark matter asymmetries that are then partially converted into a baryon asymmetry. Consequently, we show how to explain the matter-antimatter asymmetry, the dark matter relic density and neutrino masses in theories for local baryon and lepton number.
description: 18 pages, 8 figures. v2 References added, to appear in PRD
The finite tiling problem is undecidable in the hyperbolic plane
Creators: name: Margenstern, Maurice
Publisher: name: arXiv
Year: 2007
Subjects: subject: Computational Geometry (cs.CG)
subject: Discrete Mathematics (cs.DM)
subject: FOS: Computer and information sciences
subject: F.2.2; G.2.1

description: In this paper, we consider the finite tiling problem which was proved undecidable in the Euclidean plane by Jarkko Kari in 1994. Here, we prove that the same problem for the hyperbolic plane is also undecidable.
$J/ψ$ polarization in high multiplicity $pp$ and $pA$ collisions: CGC+NRQCD approach
Creators: name: Stebel, Tomasz
name: Watanabe, Kazuhiro
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Quarkonium production mechanism in high multiplicity small collision systems has recently been pursued in the color-glass-condensate (CGC) effective theory combined with non-relativistic QCD (NRQCD) factorization, allowing to study initial state interactions. Quarkonium polarization, potentially measured in future experiments, would help elucidate the quarkonium production mechanism at high multiplicities. In this paper, we provide predictions on $J/ψ$ polarization parameters in high multiplicity proton-proton ($pp$) and proton-nucleus ($pA$) collisions within the CGC+NRQCD framework. Theoretical predictions are given for $J/ψ$ rapidity $2.5< y_{J/ψ}<4$, charged-particle multiplicity pseudorapidity $|η_{ch} | <1$ and energies $\sqrt{S}=13\mathrm{~TeV}$ for $pp$, $\sqrt{S}=8.16\mathrm{~TeV}$ for $pA$ collisions. Considering two leptonic frame choices (Collins - Soper and helicity) we find a weak polarization of $J/ψ$ that additionally decreases with growing event activities. No significant system size dependence between $pp$ and $pA$ collisions is obtained - this could be a new constraint to initial state interactions in small collision systems.
description: 9 pages, 1 figure
Schwinger pair production of magnetic monopoles: momentum distribution for heavy-ion collisions
Creators: name: Gould, Oliver
name: Ho, David L. -J.
name: Rajantie, Arttu
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Magnetic monopoles may be produced by the dual Schwinger effect in strong magnetic fields. Today, the strongest known magnetic fields in the universe are produced fleetingly in heavy-ion collisions. We use the complex worldline instanton method to calculate the momentum distribution of magnetic monopoles produced in heavy-ion collisions, in an approximation that includes the effect of the magnetic field to all orders but neglects monopole self-interactions. The result saturates the preparation time-energy uncertainty principle, and yields a necessary ingredient for experimental monopole searches in heavy-ion collisions.
description: 12 pages, 3 figures
Higher Loop Bethe Ansatz for Open Spin-Chains in AdS/CFT
Creators: name: Okamura, Keisuke
name: Yoshida, Kentaroh
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We propose a perturbative asymptotic Bethe ansatz (PABA) for open spin-chain systems whose Hamiltonians are given by matrices of anomalous dimension for composite operators, and apply it to two types of composite operators related to two different brane configurations. One is an AdS_4 \times S^2-brane in the bulk AdS_5 \times S^5 which gives rise to a defect conformal field theory (dCFT) in the dual field theory, and the other is a giant graviton system with an open string excitation. In both cases, excitations on open strings attaching to D-branes (a D5-brane for the dCFT case, and a spherical D3-brane for the giant graviton case) can be represented by magnon states in the spin-chains with appropriate boundary conditions, in which informations of the D-branes are encoded. We concentrate on single-magnon problems, and explain how to calculate boundary S-matrices via the PABA technique. We also discuss the energy spectrum in the BMN limit.
description: 1+24 pages, 1 figure, typos corrected, references added, discussions on the integrability for giant gravitons modified, version to appear in JHEP
Microcomputers in psychological experimentation, headturn: a case study
Creators: name: Pidcock, Brian
Publisher: name: University of British Columbia
Year: 2008

description: Mass market microcomputers are often used in conducting psychology experiments. Despite steadily falling prices and widespread use of these microcomputers in many areas, there are significant obstacles to their universal use in psychological experimentation. The specialized needs of experimentation are often poorly served by mass market systems, yet the small size of the psychology market precludes the development of low cost, specialized hardware and software. The "Headturn" technique, an experimental protocol for studying sound and speech recognition in infants, was taken as an example of an experimental procedure that has evolved as the computer tools have evolved. This evolution is traced and the current state of the "Headturn" technique is documented and analyzed. The next step in the evolution of the "Headturn" technique has been designed and implemented to take advantage of current mass market components, capitalizing on the lessons learned using earlier versions of the system. Timing is one example where the needs of the experimenter are not readily met by mass market components. Different options for improved timing in the "Headturn" procedure were explored and implemented. Timing limits relative to experimental needs are discussed.
Direct TPE Measurement via $e^+p/e^-p$ Scattering at low $\varepsilon$ in Hall A
Creators: name: Cline, Ethan
name: Bernauer, Jan C.
name: Schmidt, Axel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The proton elastic form factor ratio can be measured either via Rosenbluth separation in an experiment with unpolarized beam and target, or via the use of polarization degrees of freedom. However, data produced by these two approaches show a discrepancy, increasing with $Q^2$. The proposed explanation of this discrepancy - two-photon exchange - has been tested recently by three experiments. The results support the existence of a small two-photon exchange effect but cannot establish that theoretical treatments at the measured momentum transfers are valid. At larger momentum transfers, theory remains untested, and without further data, it is impossible to resolve the discrepancy. A positron beam at Jefferson Lab allows us to directly measure two-photon exchange over an extended $Q^2$ and $ε$ range with high precision. With this, we can validate whether the effect reconciles the form factor ratio measurements, and test several theoretical approaches, valid in different parts of the tested $Q^2$ range. In this proposal, we describe a measurement program in Hall A that combines the Super BigBite, BigBite, and High Resolution Spectrometers to directly measure the two-photon effect. Though the limited beam current of the positron beam will restrict the kinematic reach, this measurement will have very small systematic uncertainties, making it a clean probe of two photon exchange.
description: 8 pages, 6 figures, 1 table
Editorial
Creators: name: Marques, Rui Pedro
name: Vieira, Elisabete
name: Azevedo, Graça
name: Marques, Susana
Publisher: name: International Journal of Business Innovation
Year: 2024

description: It is with great pleasure that we present the second issue of Volume 3 of the International Journal of Business Innovation. This issue once again reflects our commitment to publishing cutting-edge and high-quality research focused on critical topics shaping today’s business environment. The collaboration between authors, reviewers, and our editorial team continues to drive the success of this journal, ensuring both the relevance and quality of the articles presented.


In this edition, we are excited to share a collection of articles addressing contemporary issues in areas such as gender representation, fiscal complexity, and investor decision-making. The diversity of themes covered in this issue highlights the complexity and dynamism of the business world, offering comprehensive insights valuable to both academia and industry professionals.


The first article, "Female Under-Representation in Audit Profession and Leadership: A Study in the Portuguese Context" by Sílvia Bernardo, Isabel Pedrosa, and Daniela Monteiro, explores the under-representation of women in the audit profession in Portugal, particularly in leadership positions. This study delves into the historical and social barriers women face in advancing their careers and offers pathways to overcoming these challenges. Additionally, the paper contributes to the United Nations' Sustainable Development Goal 5 on gender equality, providing a significant contribution to this pressing global issue.


Next, the article "Autonomous Taxation in Portugal: The Cost of a Tricky Law" by Rita Gigante, Ana Arromba Dinis, and Liliana Pereira, examines autonomous taxation within the Portuguese fiscal system. The study highlights the complexity of tax legislation and the associated costs stemming from disputes in arbitration courts. This work is highly relevant for both professionals and academics in the fields of accounting and taxation, offering valuable insights into the need for simplification and clarity in tax law to improve efficiency and reduce litigation.


Our final article, "The Influence of Persuasion on Investor Decision-Making: An Analysis in Light of the Prospect Theory" by Cleber Broietti and Suliani Rover, investigates how persuasion affects investor decision-making within the context of prospect theory. Through an experimental study involving university students, the authors demonstrate how persuasive arguments from financial analysts can mitigate the impact of gains and losses presented in companies’ financial reports, significantly altering the behavior of non-professional investors.


We extend our sincere gratitude to all the authors for their valuable contributions and to the reviewers for their diligent and insightful feedback. We are excited about the future of the International Journal of Business Innovation and look forward to bringing you more groundbreaking research in upcoming issues.
description: International Journal of Business Innovation, Volume 3 Issue 2 (2024)
ΜΜΕ και επιφυλλιδογραφία: η στήλη του Μάριου Πλωρίτη στην εφημερίδα Το Βήμα
Creators: name: Γρηγορίου, Μαριορή Κωνσταντίνου
Publisher: name: Aristotle University of Thessaloniki
Year: 2019
Subjects: Μάριος Πλωρίτης
Επιφυλλίδα
Σχολιαστική δημοσιογραφία
Marios Ploritis
Epifillida
Opinion Journalism

description: Η παρούσα εργασία μελετά την επιφυλλίδα ως είδος της Αρθρογραφίας Γνώμης (Opinion Journalism). Αντιπροσωπευτικό δείγμα για την έρευνά μας αποτέλεσε η στήλη του Μάριου Πλωρίτη (μελέτη περίπτωσης), η οποία φιλοξενήθηκε από το 1974 μέχρι το 2006 στην κυριακάτικη έκδοση της εφημερίδας «Το Βήμα», ενώ τα κείμενά του εξακολουθούν να είναι αναρτημένα στο ψηφιακό αρχείο της εφημερίδας. Με βάση ένα εκτενές σώμα άρθρων του συγκεκριμένου δημοσιογράφου-επιφυλλιδογράφου, το οποίο περιλαμβάνεται στην έκδοση «Μάριος Πλωρίτης – Επιφυλλίδες 1989-2004» του Ιδρύματος της Βουλής των Ελλήνων, η μελέτη μας επιχειρεί: α) να προσδιορίσει το σχολιογραφικό είδος της επιφυλλίδας ως κειμενικό προϊόν, αναδεικνύοντας το ιστορικό πλαίσιο, τη φυσιογνωμία και τις λειτουργίες του, β) να αποτυπώσει τα ιδιαίτερα κειμενικά, δομικά, υφολογικά και ιδεολογικά χαρακτηριστικά του έργου του Μάριου Πλωρίτη, ενός από τους βασικότερους εκπροσώπους του είδους στον νεοελληνικό Τύπο και γ) να διαπιστώσει εάν τελικά και με ποιους τρόπους το επιφυλλιδογραφικό έργο του συγγραφέα, που υπήρξε υπόδειγμα πολύπλευρου διανοούμενου στα μεταπολεμικά ελληνικά γράμματα, με σημαντικό έργο στους τομείς της θεατρικής κριτικής και σκηνοθεσίας, της λογοτεχνίας και της μετάφρασης, συνδέεται και εμπλουτίζεται με τις θεματικές της τέχνης και τις πιο δημιουργικές πρακτικές της λογοτεχνικής γραφής
description: The present research intends to study “epifillida” as a type of Opinion Journalism. The column of Marios Plotitis, which was hosted at the Sunday newspaper “To Vima” during 1974-2006, and it is still included and uploaded on the electronic version of the newspaper, was used as a representative sample (case study). Based on an extensive corpus of texts of the aforesaid journalist, taken from the publication “Marios Ploritis - Epifillides 1989-2004” of the Hellenic Parliament Foundation our study attempts: a) to define the columnist type of “epifillida” as a textual product, and highlight its historical texture, features and functions b) to illustrate the distinctive textual, structural, stylistic and ideological characteristics of Ploritis’s work, as one of the most important representatives of “epifillida” in modern Greek Press, and c) to ascertain whether and in which way Ploritis’s work, who has been an eminent intellectual in Greek post-war literary with significant activity in the fields of theatre review and theatre direction, literature and translation, is affiliated and enriched with themes of art and the most creative practices of literature writing
The Shadow of Dark Matter
Creators: name: Profumo, Stefano
name: Sigurdson, Kris
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We carry out a model independent study of resonant photon scattering off dark matter (DM) particles. The DM particle chi_1 can feature an electric or magnetic transition dipole moment which couples it with photons and a heavier neutral particle chi_2. Resonant photon scattering then takes place at a special energy set by the masses of chi_1 and chi_2, with the width of the resonance set by the size of the transition dipole moment. We compute the constraints on the parameter space of the model from stellar energy losses, data from SN 1987A, the Lyman-alpha forest, Big Bang nucleosynthesis, electro-weak precision measurements and accelerator searches. We show that the velocity broadening of the resonance plays an essential role for the possibility of the detection of a spectral feature originating from resonant photon-DM scattering. Depending upon the particle setup and the DM surface mass density, the favored range of DM particle masses lies between tens of keV and a few MeV, while the resonant photon absorption energy is predicted to be between tens of keV and few GeV.
description: 8 pages, 6 figures, submitted to PRD
Time Integrator Agnostic Charge Conserving Finite Element PIC
Creators: name: O'Connor, Scott
name: Crawford, Zane D.
name: Ramachandran, O. H.
name: Luginsland, John
name: Shanker, B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Developing particle-in-cell (PIC) methods using finite element basis sets, and without auxiliary divergence cleaning methods, was a long standing problem until recently. It was shown that if consistent spatial basis functions are used, one can indeed create a methodology that was charge conserving, albeit using a leap-frog time stepping method. While this is a significant advance, leap frog schemes are only conditionally stable and time step sizes are closely tied to the underlying mesh. Ideally, to take full advantage of advances in finite element methods (FEMs), one needs a charge conserving PIC methodology that is agnostic to the time stepping method. This is the principal contribution of this paper. In what follows, we shall develop this methodology, prove that both charge and Gauss' laws are discretely satisfied at every time step, provide the necessary details to implement this methodology for both the wave equation FEM and Maxwell Solver FEM, and finally demonstrate its efficacy on a suite of test problems. The method will be demonstrated by single particle evolution, non-neutral beams with space-charge, and adiabatic expansion of a neutral plasma, where the debye length has been resolved, and real mass ratios are used.
description: The following article has been submitted to AIP Physics of Plasmas
Controlling quantum interference between virtual and dipole two-photon optical excitation pathways using phase-shaped laser pulses
Creators: name: Lahiri, Jurick
name: Yuwono, Stephen H.
name: Magoulas, Ilias
name: Moemeni, Mehdi
name: Borhan, Babak
name: Blanchard, G. J.
name: Piecuch, Piotr
name: Dantus, Marcos
Publisher: name: arXiv
Year: 2021
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Two-photon excitation (TPE) proceeds via a "virtual" pathway, which depends on the accessibility of one or more intermediate states, and, in the case of non-centrosymmetric molecules, an additional "dipole" pathway involving the off-resonance dipole-allowed one-photon transitions and the change in the permanent dipole moment between the initial and final states. Here, we control the quantum interference between these two optical excitation pathways by using phase-shaped femtosecond laser pulses. We find enhancements by a factor of up to 1.75 in the two-photon-excited fluorescence of the photobase FR0-SB in methanol after taking into account the longer pulse duration of the shaped laser pulses. Simulations taking into account the different responses of the virtual and dipole pathways to external fields and the effect of pulse shaping on two-photon transitions are found to be in good agreement with our experimental measurements. The observed quantum control of TPE in condensed phase may lead to enhanced signal at a lower intensity in two-photon microscopy, multiphoton-excited photoreagents, and novel spectroscopic techniques that are sensitive to the magnitude of the contributions from the virtual and dipole pathways to multiphoton excitations.
description: 27 pages, 6 figures, 1 scheme. This article has been accepted for publication in the Journal of Physical Chemistry A
Hupa language lesson
Creators: name: Parker, Verdena
name: Escamilla, Ramón
name: Newbold, Lindsey
name: Spence, Justin
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2021
Subjects: subject: hup

description: Audio files VP-131007-01 and VP-131007-02: Language lesson focused on parts of the face, the phrase 'What's this?', and simple commands.
Tl2Ba2CuO6+d Brings Spectroscopic Probes Deep Into the Overdoped Regime of the High-Tc Cuprates
Creators: name: Peets, D. C.
name: Mottershead, J. D. F.
name: Wu, B.
name: Elfimov, I. S.
name: Liang, R.
name: Hardy, W. N.
name: Bonn, D. A.
name: Raudsepp, M.
name: Ingle, N. J. C.
name: Damascelli, A
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Single-particle spectroscopic probes, such as scanning tunneling and angle-resolved photoemission spectroscopy (ARPES), have provided us with crucial insights into the complex electronic structure of the high-Tc cuprates, in particular for the under and optimally doped regimes where high-quality crystals suitable for surface-sensitive experiments are available. Conversely, the elementary excitations on the heavily overdoped side of the phase diagram remain largely unexplored. Important breakthroughs could come from the study of Tl2Ba2CuO6+d (Tl2201), a structurally simple system whose doping level can be tuned from optimal to extreme overdoping by varying the oxygen content. We have grown single crystals of Tl2201, which were then carefully annealed under controlled oxygen partial pressures. Their high quality and homogeneity are demonstrated by narrow rocking curves and superconducting transition widths. These crystals have enabled the first successful ARPES study of both normal and superconducting-state electronic structure in Tl2201, allowing a direct comparison with the Fermi surface from magnetoresistance and the gap from thermal conductivity experiments. This establishes Tl2201 as the first high-Tc cuprate for which a surface-sensitive single-particle spectroscopy and a comparable bulk transport technique have arrived at quantitative agreement on a major feature such as the normal state Fermi surface. The surprising momentum dependence of the ARPES lineshape is also discussed.
description: Submitted to New Journal of Physics (partly a replacement for cond-mat/0211028). A high-resolution version can be found at http://www.physics.ubc.ca/~quantmat/ARPES/PUBLICATIONS/Articles/Tl_NJP.pdf and related material at http://www.physics.ubc.ca/~quantmat/ARPES/PUBLICATIONS/articles.html
A Physics-informed data reconciliation framework for real-time electricity and emissions tracking
Creators: name: de Chalendar, Jacques A
name: Benson, Sally M
Publisher: name: arXiv
Year: 2021
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: To encourage and guide decarbonization efforts, better tools are needed to monitor real-time CO2 and criteria air pollutant emissions from electricity consumption, production, imports, and exports. Using real-time data from the electricity system is especially challenging for quantitative applications requiring high quality and physically consistent data. Until now, time-intensive, ad-hoc and manual data verification and cleaning strategies have been used to prepare the data for quantitative analysis. As an alternative to existing techniques, here we provide a physics-informed framework to greatly accelerate and automate data processing to enable internally consistent electric system consumption, production, import, and export data in near real-time. A key component of this framework is an optimization program to minimize the data adjustments required to satisfy energy conservation equations. The effectiveness of this method is demonstrated by applying it to the continental United States electricity network. The resulting publicly-available data set, which provides in near-real time, hourly updates on electricity generation, consumption, imports, exports and associated emissions, is the first of this nature.
description: A short version of this paper was presented at Applied Energy Symposium: MIT A+B, August 13-14, 2020, Boston. This paper is a substantial extension of the short version of the conference paper
Global geometry of the supersymmetric AdS_3/CFT_2 correspondence in M-theory
Creators: name: Figueras, Pau
name: Mac Conamhna, Oisin A. P.
name: Colgain, Eoin O
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the global geometry of a general class of spacetimes of relevance to the supersymmetric $AdS_3/CFT_2$ correspondence in eleven-dimensional supergravity. Specifically, we study spacetimes admitting a globally-defined $\mathbb{R}^{1,1}$ frame, a globally-defined frame bundle with structure group contained in Spin(7), and an $AdS_3$ event horizon or conformal boundary. We show how the global frame bundle may be canonically realised by globally-defined null sections of the spin bundle, which we use to truncate eleven-dimensional supergravity to a gravitational theory of a frame with structure group Spin(7), SU(4) or Sp(2). By imposing an $AdS_3$ boundary condition on the truncated supergravity equations, we define the geometry of all $AdS_3$ horizons or boundaries which can be obtained from solutions of these truncations. In the most generic case we study, we reproduce the most general conditions for an $AdS_3$ manifold in M-theory to admit a Killing spinor. As a consistency check on our definitions of $AdS$ geometries we verify that they are satisfied by known gauged supergravity $AdS_3$ solutions. We discuss future applications of our results.
description: 1+48 pages, 1 figure
CoreNet: A Network Method to Identify Differential Gene Interactions
Creators: name: Banh, David N
name: Nguyen, Quan H
Publisher: name: F1000 Research Limited
Year: 2019

description: Single-cell RNA expression datasets are sparse and variable - therefore they require analysis frameworks that are robust to the stochastic variation of a single gene or a small gene subset. We develop a network-analysis algorithm, CoreNet, which enables simultaneous comparisons of multiple gene-expression networks to identify essential genes with differential network interaction properties across cell-types in singular, pair-wise and multiple network comparisons. CoreNet identifies differences in network topologies through network graphlet statistics. Graphlets are the smallest subnetwork structures consisting of all possible combinations of edges existing between two to four genes, and thus representing gene-gene interactions. Taking each gene as the root, we counted intersecting graphlets and counts are transformed into Chi-square statistics. Compared to other network approaches, CoreNet allows for statistical significance testing and biological inference of important differential interacting genes. We show that the network approach finds genes that are significantly different in interactions and are not detectable by traditional gene-centric analysis. CoreNet, therefore, can be an important method complementary to the traditional differential expression analysis approaches.
The Physical Drivers of the Luminosity-Weighted Dust Temperatures in High-Redshift Galaxies
Creators: name: Burnham, Anne D.
name: Casey, Caitlin M.
name: Zavala, Jorge A.
name: Manning, Sinclaire M.
name: Spilker, Justin S.
name: Chapman, Scott C.
name: Chen, Chian-Chou
name: Cooray, Asantha
name: Sanders, David B.
name: Scoville, Nick Z.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The underlying distribution of galaxies' dust SEDs (i.e., their spectra re-radiated by dust from rest-frame $\sim$3$μ$m-3mm) remains relatively unconstrained due to a dearth of FIR/(sub)mm data for large samples of galaxies. It has been claimed in the literature that a galaxy's dust temperature -- observed as the wavelength where the dust SED peaks ($λ_{peak}$) -- is traced most closely by its specific star-formation rate (sSFR) or parameterized 'distance' to the SFR-M$_\star$ relation (the galaxy 'main sequence'). We present 0.24" resolved 870$μ$m ALMA dust continuum observations of seven $z=1.4-4.6$ dusty star-forming galaxies (DSFGs) chosen to have a large range of well-constrained luminosity-weighted dust temperatures. We also draw on similar resolution dust continuum maps from a sample of ALESS submillimeter galaxies from Hodge et al. (2016). We constrain the physical scales over which the dust radiates and compare those measurements to characteristics of the integrated SED. We confirm significant correlations of $λ_{peak}$ with both L$_{IR}$ (or SFR) and $Σ_{\rm IR}$ ($\propto$SFR surface density). We investigate the correlation between $\log_{10}$($λ_{peak}$) and $\log_{10}$($Σ_{\rm IR}$) and find the relation to hold as would be expected from the Stefan-Boltzmann Law, or the effective size of an equivalent blackbody. The correlations of $λ_{peak}$ with sSFR and distance from the SFR-M$_\star$ relation are less significant than those for $Σ_{\rm IR}$ or L$_{IR}$; therefore, we conclude that the more fundamental tracer of galaxies' luminosity-weighted integrated dust temperatures are indeed their star-formation surface densities in line with local Universe results, which relate closely to the underlying geometry of dust in the ISM.
description: 18 pages, 7 figures, accepted for publication in ApJ
Threshold of coexistence and critical behavior of a predator-prey cellular automaton
Creators: name: Arashiro, Everaldo
name: Tome, Tania
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study a probabilistic cellular automaton to describe two population biology problems: the threshold of species coexistence in a predator-prey system and the spreading of an epidemic in a population. By carrying out time-dependent simulations we obtain the dynamic critical exponents and the phase boundaries (thresholds) related to the transition between an activestate, where prey and predators present a stable coexistence, and a prey absorbing state. The estimates for the critical exponents show that the transition belongs to the directed percolation universality class. In the limit where the cellular automaton maps into a model for the spreading of an epidemic with immunization we observe a crossover from directed percolation class to the dynamic percolation class. Patterns of growing clusters related to species coexistence and spreading of epidemic are shown and discussed.
description: 10 pages, 11 figures
MCTSteg: A Monte Carlo Tree Search-based Reinforcement Learning Framework for Universal Non-additive Steganography
Creators: name: Mo, Xianbo
name: Tan, Shunquan
name: Li, Bin
name: Huang, Jiwu
Publisher: name: arXiv
Year: 2021
Subjects: subject: Multimedia (cs.MM)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Recent research has shown that non-additive image steganographic frameworks effectively improve security performance through adjusting distortion distribution. However, as far as we know, all of the existing non-additive proposals are based on handcrafted policies, and can only be applied to a specific image domain, which heavily prevent non-additive steganography from releasing its full potentiality. In this paper, we propose an automatic non-additive steganographic distortion learning framework called MCTSteg to remove the above restrictions. Guided by the reinforcement learning paradigm, we combine Monte Carlo Tree Search (MCTS) and steganalyzer-based environmental model to build MCTSteg. MCTS makes sequential decisions to adjust distortion distribution without human intervention. Our proposed environmental model is used to obtain feedbacks from each decision. Due to its self-learning characteristic and domain-independent reward function, MCTSteg has become the first reported universal non-additive steganographic framework which can work in both spatial and JPEG domains. Extensive experimental results show that MCTSteg can effectively withstand the detection of both hand-crafted feature-based and deep-learning-based steganalyzers. In both spatial and JPEG domains, the security performance of MCTSteg steadily outperforms the state of the art by a clear margin under different scenarios.
description: accepted by TIFS
Star-forming Regions in the Small Magellanic Cloud Multi-wavelength Properties of Stellar Complexes
Creators: name: Livanou, E.
name: Gonidakis, I.
name: Kontizas, E.
name: Klein, U.
name: Kontizas, M.
name: Kester, D.
name: Fukui, Y.
name: Mizuno, N.
name: Tsalmantza, P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We trace the star formation regions in the SMC and study their properties. The size and spatial distribution of these regions is found to support the hierarchical scenario of star formation, whereas, the evaluation of their intensity, contributes to the understanding of the various stages of star formation. Their connection to the LMC-SMC close encounter, about $(0.9-2) \times 10^{8}$ years ago, is investigated as well. The SMC, being almost edge-on, does not easily reveal these areas, as is the case with the LMC. However, a study through multi-wavelength images such as optical, IR and radio has been proved very useful. A selection of areas, with enhanced 60 and 100-$μ$m infrared flux and emission in all IRAS bands, identifies the star forming regions. All of the identified regions are dominated by early-type stars and considering their overall size (increasing order) a total of 24 aggregates, 23 complexes, and 3 super-complexes were found. We present their coordinates, dimensions, and IR fluxes. Moreover, we correlate their positions with known associations, SNRs, and \hii regions and discuss their activity.
DREAM: a fluid-kinetic framework for tokamak disruption runaway electron simulations
Creators: name: Hoppe, M.
name: Embreus, O.
name: Fülöp, T.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Avoidance of the harmful effects of runaway electrons (REs) in plasma-terminating disruptions is pivotal in the design of safety systems for magnetic fusion devices. Here, we describe a computationally efficient numerical tool, that allows for self-consistent simulations of plasma cooling and associated RE dynamics during disruptions. It solves flux-surface averaged transport equations for the plasma density, temperature and poloidal flux, using a bounce-averaged kinetic equation to self-consistently provide the electron current, heat, density and RE evolution, as well as the electron distribution function. As an example, we consider disruption scenarios with material injection and compare the electron dynamics resolved with different levels of complexity, from fully kinetic to fluid modes.
description: 33 pages, 11 figures