cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Three-Dimensional Structure of the Magnetic Field in the Disk of the Milky Way
Creators: name: Ordog, A.
name: Brown, J. C.
name: Kothes, R.
name: Landecker, T. L.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present Rotation Measures (RM) of the diffuse Galactic synchrotron emission from the Canadian Galactic Plane Survey (CGPS) and compare them to RMs of extragalactic sources in order to study the large-scale reversal in the Galactic magnetic field (GMF). Using Stokes Q, U and I measurements of the Galactic disk collected with the Synthesis Telescope at the Dominion Radio Astrophysical Observatory, we calculate RMs over an extended region of the sky, focusing on the low longitude range of the CGPS (l=52deg to l=72deg). We note the similarity in the structures traced by the compact sources and the extended emission and highlight the presence of a gradient in the RM map across an approximately diagonal line, which we identify with the well-known field reversal of the Sagittarius-Carina arm. We suggest that the orientation of this reversal is a geometric effect resulting from our location within a GMF structure arising from current sheets that are not perpendicular to the Galactic plane, as is required for a strictly radial field reversal, but that have at least some component parallel to the disk. Examples of models that fit this description are the three-dimensional dynamo-based model of Gressel et al. (2013) and a Galactic scale Parker spiral (Akasofu & Hakamada 1982), although the latter may be problematic in terms of Galactic dynamics. We emphasize the importance of constructing three-dimensional models of the GMF to account for structures like the diagonal RM gradient observed in this dataset.
description: Published in Astronomy and Astrophysics, Accepted 23 April, 2017
Three-dimensional Turbulent Reconnection within Solar Flare Current Sheet
Creators: name: Wang, Yulei
name: Cheng, Xin
name: Ding, Mingde
name: Liu, Zhaoyuan
name: Liu, Jian
name: Zhu, Xiaojue
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Solar flares can release coronal magnetic energy explosively and may impact the safety of near-earth space environments. Their structures and properties on macroscale have been interpreted successfully by the generally-accepted two-dimension standard model invoking magnetic reconnection theory as the key energy conversion mechanism. Nevertheless, some momentous dynamical features as discovered by recent high-resolution observations remain elusive. Here, we report a self-consistent high-resolution three-dimension magnetohydrodynamical simulation of turbulent magnetic reconnection within a flare current sheet. It is found that fragmented current patches of different scales are spontaneously generated with a well-developed turbulence spectrum at the current sheet, as well as at the flare loop-top region. The close coupling of tearing-mode and Kelvin-Helmholtz instabilities plays a critical role in developing turbulent reconnection and in forming dynamical structures with synthetic observables in good agreement with realistic observations. The sophisticated modeling makes a paradigm shift from the traditional to three-dimension turbulent reconnection model unifying flare dynamical structures of different scales.
description: 15 pages, 8 figure, accepted for publication in ApJL
Correlation between resource-generating capacities of quantum gates
Creators: name: Bhattacharyya, Aparajita
name: Ghoshal, Ahana
name: Sen, Ujjwal
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We analyze the optimal basis for generating the maximum relative entropy of quantum coherence by an arbitrary gate on a two-qubit system. The optimal basis is not unique, and the high quantum coherence generating gates are also typically high entanglement generating ones and vice versa. However, the profile of the relative frequencies of Haar random unitaries generating different amounts of entanglement for a fixed amount of quantum coherence is different from the one in which the roles of entanglement and quantum coherence are reversed, although both follow the beta distribution.
description: 15 pages, 7 figures
Real-Time Instance and Semantic Segmentation Using Deep Learning
Creators: name: Kolhatkar, Dhanvin
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2020
Subjects: Instance segmentation
Semantic segmentation
Deep learning
Real-time
Mask prediction

description: In this thesis, we explore the use of Convolutional Neural Networks for semantic and instance segmentation, with a focus on studying the application of existing methods with cheaper neural networks. We modify a fast object detection architecture for the instance segmentation task, and study the concepts behind these modifications both in the simpler context of semantic segmentation and the more difficult context of instance segmentation. Various instance segmentation branch architectures are implemented in parallel with a box prediction branch, using its results to crop each instance's features. We negate the imprecision of the final box predictions and eliminate the need for bounding box alignment by using an enlarged bounding box for cropping. We report and study the performance, advantages, and disadvantages of each. We achieve fast speeds with all of our methods.
Uniform probability in cosmology
Creators: name: Wenmackers, Sylvia
Publisher: name: arXiv
Year: 2023
Subjects: subject: History and Philosophy of Physics (physics.hist-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Probability (math.PR)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Problems with uniform probabilities on an infinite support show up in contemporary cosmology. This paper focuses on the context of inflation theory, where it complicates the assignment of a probability measure over pocket universes. The measure problem in cosmology, whereby it seems impossible to pick out a uniquely well-motivated measure, is associated with a paradox that occurs in standard probability theory and crucially involves uniformity on an infinite sample space. This problem has been discussed by physicists, albeit without reference to earlier work on this topic. The aim of this article is both to introduce philosophers of probability to these recent discussions in cosmology and to familiarize physicists and philosophers working on cosmology with relevant foundational work by Kolmogorov, de Finetti, Jaynes, and other probabilists. As such, the main goal is not to solve the measure problem, but to clarify the exact origin of some of the current obstacles. The analysis of the assumptions going into the paradox indicates that there exist multiple ways of dealing consistently with uniform probabilities on infinite sample spaces. Taking a pluralist stance towards the mathematical methods used in cosmology shows there is some room for progress with assigning probabilities in cosmological theories.
description: 16 pages; accepted for publication in Studies in History and Philosophy of Science
Learning Deep NBNN Representations for Robust Place Categorization
Creators: name: Mancini, Massimiliano
name: Bulò, Samuel Rota
name: Ricci, Elisa
name: Caputo, Barbara
Publisher: name: arXiv
Year: 2017
Subjects: subject: Robotics (cs.RO)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: This paper presents an approach for semantic place categorization using data obtained from RGB cameras. Previous studies on visual place recognition and classification have shown that, by considering features derived from pre-trained Convolutional Neural Networks (CNNs) in combination with part-based classification models, high recognition accuracy can be achieved, even in presence of occlusions and severe viewpoint changes. Inspired by these works, we propose to exploit local deep representations, representing images as set of regions applying a Naïve Bayes Nearest Neighbor (NBNN) model for image classification. As opposed to previous methods where CNNs are merely used as feature extractors, our approach seamlessly integrates the NBNN model into a fully-convolutional neural network. Experimental results show that the proposed algorithm outperforms previous methods based on pre-trained CNN models and that, when employed in challenging robot place recognition tasks, it is robust to occlusions, environmental and sensor changes.
Continuous families of non-Hermitian surface solitons
Creators: name: Zezyulin, Dmitry A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We show that surface solitons form continuous families in one-dimensional complex optical potentials of a certain shape. This result is illustrated by non-Hermitian gap-surface solitons at the interface between a uniform conservative medium and a complex periodic potential. Surface soliton families are parameterized by a real propagation constant. The range of possible propagation constants is constrained by the relation between the continuous spectrum of the uniform medium and the band-gap structure of the periodic potential.
description: 5 pages, 5 figures; to appear in Optics Letters
Relevante Faktoren bei der Umsetzung der BIM-Methode in einer öffentlichen Organisation unter Berücksichtigung des Umfeldes
Creators: name: Stalder, Ivo
Publisher: name: Hochschule für Architektur, Bau und Geomatik FHNW
Year: 2024
Subjects: subject: BIM
subject: Öffentliche Organisation
subject: Infrastrukturbau
subject: Kunstbauten
subject: Prozessmodellierung
subject: Datenmodellierung
subject: Visualisierung
subject: 600 - Technik, Medizin, angewandte Wissenschaften

description: Die Einführung der BIM-Methode in öffentlichen Organisationen stellt eine komplexe Herausforderung dar, die sowohl organisatorische als auch technologische Anpassungen erfordert. Diese Arbeit untersucht die relevanten Faktoren für die Umsetzung der BIM-Methode im Tiefbauamt des Kantons St. Gallen, insbesondere im Bereich der Kunstbauten Infrastruktur. Die zentrale Fragestellung dieser Arbeit ist, welche Bestandteile notwendig sind, um die BIM-Methode erfolgreich umsetzen zu können. Die Arbeitsmethodik umfasst qualitative Interviews mit Schlüsselakteuren und eine umfassende Analyse der bestehenden Prozesse und Systeme. Visualisierungstechniken und Prozessanalysen werden eingesetzt, um die Kommunikation und das Verständnis zwischen den Beteiligten zu fördern. Die Betrachtungen zeigen, dass eine schrittweise Einführung der BIM-Methode sowie die Förderung des Verständnisses unter den Akteuren entscheidend für die Akzeptanz und den Erfolg sind. Pilotprojekte spielen dabei eine wesentliche Rolle, um praktische Erfahrungen sammeln zu können und die Methodenumsetzung kontinuierlich zu optimieren. Die Ergebnisse beleuchten einen Ansatz für die Herangehensweise an die BIM-Methode, welcher von Organisationen für dessen Umsetzung herangezogen werden kann. In der Arbeit werden dafür konkrete Werkzeuge vorgeschlagen. Neben technologischen Anpassungen sind auch arbeitstechnische Veränderungen für den Umsetzungserfolg von Relevanz. Diese projektähnlich umgesetzte Arbeit soll einen Beitrag zum digitalen Planen und Bauen leisten und anhand der gewonnenen Erkenntnisse Empfehlungen für die Umsetzung der BIM-Methode in öffentlichen Organisationen bieten.
Withdrawing a solid from a bath: how much liquid is coated?
Creators: name: Rio, Emmanuelle
name: Boulogne, François
Publisher: name: arXiv
Year: 2016
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: A solid withdrawn from a liquid bath entrains a film. In this review, after recalling the predictions and results for pure Newtonian liquids coated on simple solids, we analyze the deviations to this ideal case exploring successively three potential sources of complexity: the liquid-air interface, the bulk rheological properties of the liquid and the mechanical or chemical properties of the solid. For these different complexities, we show that significant effects on the film thickness are observed experimentally and we summarize the theoretical analysis presented in the literature, which attempt to rationalize these measurements.
Weyl-type bounds for twisted $GL(2)$ short character sums
Creators: name: Ghosh, Aritra
Publisher: name: arXiv
Year: 2021
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11F66 (11F55, 11M41), 11F30

description: Let f be a Hecke-Maass or holomorphic primitive cusp form for $SL(2,\mathbb{Z})$ with Fourier coefficients $λ_{f}(n)$. Let $χ$ be a primitive Dirichlet character of modulus p, where p is a prime number. In this article we prove the following Weyl-type bound: for any $ε>0$, $$\sum_{|n| \ll N}λ_{f}(n)χ(n) \ll_{f,ε}N^{3/4 }p^{1/6}(pN)^ε.$$ We can see an improvement of the range $N > p^{3/4}$ to the range $N > p^{2/3}$ and we get a bound for $S_{f,χ}(N)$ without going into the $L$-function.
description: Final verson, appeared in The Ramanujan Journal (2022)
Precise predictions for dijet production at the LHC
Creators: name: Currie, James
name: Ridder, Aude Gehrmann-De
name: Gehrmann, Thomas
name: Glover, E. W. N.
name: Huss, Alexander
name: Pires, Joao
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We present the calculation of dijet production, doubly-differential in dijet mass, $m_{jj}$ and rapidity difference, $|y^{*}|$, at leading colour in all partonic channels at next-to-next-to-leading order (NNLO) in perturbative QCD. We consider the long-standing problems associated with scale choice for dijet production at next-to-leading order (NLO) and investigate the impact of including the NNLO contribution. We find that the NNLO theory provides reliable predictions, even when using scale choices which display pathological behaviour at NLO. We choose the dijet invariant mass as the theoretical scale on the grounds of perturbative convergence and residual scale variation and compare the predictions to the ATLAS 7 TeV 4.5 fb$^{-1}$ data.
description: 5 pages, 5 figures
A Novel Multi-scale Attention Feature Extraction Block for Aerial Remote Sensing Image Classification
Creators: name: Sitaula, Chiranjibi
name: Aryal, Jagannath
name: Bhattacharya, Avik
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Classification of very high-resolution (VHR) aerial remote sensing (RS) images is a well-established research area in the remote sensing community as it provides valuable spatial information for decision-making. Existing works on VHR aerial RS image classification produce an excellent classification performance; nevertheless, they have a limited capability to well-represent VHR RS images having complex and small objects, thereby leading to performance instability. As such, we propose a novel plug-and-play multi-scale attention feature extraction block (MSAFEB) based on multi-scale convolution at two levels with skip connection, producing discriminative/salient information at a deeper/finer level. The experimental study on two benchmark VHR aerial RS image datasets (AID and NWPU) demonstrates that our proposal achieves a stable/consistent performance (minimum standard deviation of $0.002$) and competent overall classification performance (AID: 95.85\% and NWPU: 94.09\%).
description: The paper is under review in IEEE Geoscience and Remote Sensing Letters Journal (IEEE-GRSL). This version may be deleted and/or updated based on the journal's policy
Bayesian analysis of a relativistic hadronic model constrained by recent astrophysical observations
Creators: name: S., B. A. de Moura
name: Lenzi, C. H.
name: Lourenço, O.
name: Dutra, M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We use Bayesian analysis in order to constrain the equation of state for nuclear matter from astrophysical data related to the recent measurements from the NICER mission, LIGO/Virgo collaboration, and probability distributions of mass and radius from other 12 sources, including thermonuclear busters, and quiescent low-mass X-ray binaries. For this purpose, we base our study on a relativistic hadronic mean field model including an $ω-ρ$ interaction. Our results indicate optimal ranges for some bulk parameters at the saturation density, namely, effective mass, incompressibility, and symmetry energy slope ($L_0$). For instance, we find $L_0 = 50.79^{+15.16}_{-9.24}$ MeV (Case 1) and $L_0 = 75.06^{+8.43}_{-4.43}$ MeV (Case 2) in a $68\%$ confidence interval for the 2 cases analyzed (different input ranges for $L_0$ related to the PREX-II data). The respective parametrizations are in agreement with important nuclear matter constraints, as well as observational neutron star data, such as the dimensionless tidal deformability of the GW170817 event. From the mass-radius curves obtained from these best parametrizations, we also find the ranges of $11.97 \mbox{ km}\leqslant R_{1.4}\leqslant 12.73 \mbox{ km}$ (Case 1) and $12.34 \mbox{ km}\leqslant R_{1.4}\leqslant 13.06 \mbox{ km}$ (Case 2) for the radius of the $1.4M_\odot$ neutron star.
description: 12 pages, 11 figures, 7 tables
The He${}_2^+$ molecular ion and the He${}^-$ atomic ion in strong magnetic fields
Creators: name: Vieyra, J. C. Lopez
name: Turbiner, A. V.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the question about existence i.e. stability with respect to dissociation of the spin-quartet, permutation- and reflection-symmetric ${}^4(-3)^+_g$ ($S_z=-3/2, M=-3$) state of the $(ααe e e)$ Coulomb system: the ${\rm He}_2^+$ molecular ion, placed in a magnetic field $0 \le B \le 10000$ a.u. We assume that the $α$-particles are infinitely massive (Born-Oppenheimer approximation of zero order) and adopt the parallel configuration, when the molecular axis and the magnetic field direction coincide, as the optimal configuration. The study of the stability is performed variationally with a physically adequate trial function. To achieve this goal, we explore several Helium-contained compounds in strong magnetic fields, in particular, we study the spin-quartet ground state of ${\rm He}^-$ ion, and the ground (spin-triplet) state of the Helium atom, both for a magnetic field in $100 \leq B\leq 10000$ a.u. The main result is that the ${\rm He}_2^+$ molecular ion in the state ${}^4(-3)^+_g$ is stable towards all possible decay modes for magnetic fields $B \gtrsim 120$ a.u. and with the magnetic field increase the ion becomes more tightly bound and compact with a cigar-type form of electronic cloud. At $B=1000$ a.u., the dissociation energy of ${\rm He}_2^+$ into ${\rm He}^- + α$ is $\sim 701.8$ eV and the dissociation energy for the decay channel to ${\rm He} + α+ e $ is $\sim 729.1$ eV, latter both energies are in the energy window for one of the observed absorption features of the isolated neutron star 1E1207.4-5209.
description: LaTeX revtex4 BibTeX, 34 pages, 7 Tables and 5 Postscript Figures. Typos corrected. Several clarifying sentences were added. List of References was updated. 3 references were removed, 9 new references were added. Some sections were renamed and Section III was added
Gravitomagnetic tidal currents in rotating neutron stars
Creators: name: Poisson, Eric
name: Doucot, Jean
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It was recently revealed that a rotating compact body responds dynamically when it is subjected to a gravitomagnetic tidal field, even when this field is idealized as time-independent. The dynamical response is characterized by time-changing internal currents, and it was suspected to originate from zero-frequency g-modes and r-modes driven by the tidal forces. In this paper we provide additional insights into the phenomenon by examining the tidal response of a rotating body within the framework of post-Newtonian gravity. This approach allows us to develop an intuitive picture for the phenomenon, which relies on the close analogy between post-Newtonian gravity and Maxwell's theory of electromagnetism. In this picture, the coupling between the gravitomagnetic tidal field and the body's rotational velocity is naturally expected to produce an unbalanced Lorentz-like force within the body, and it is this force that is responsible for the tidal currents. The simplicity of the fluid equations in the post-Newtonian setting allows us to provide a complete description of the zero-frequency modes and demonstrate their precise role in the establishment of the tidal currents. We estimate the amplitude of these currents, and find that for neutron-star binaries of relevance to LIGO, the scale of the velocity perturbation is measured in kilometers per second when the rotation period is comparable to 100 milliseconds. This estimate indicates that the tidal currents may have a significant impact on the physics of neutron stars near merger.
description: 24 pages, 3 figures, final version to be published in Physical Review D
title: Second language academic literacy socialisation through individual networks of practice
title: An ethnographic account of learning to write in an academic English programme in Japan
titleType: Subtitle
Creators: name: Bankier, John
Publisher: name: Lancaster University
Year: 2019
Subjects: language socialization
membership categorization analysis
ACADEMIC DISCOURSE
Japan
ethnographic methods
academic writing
EFL

description: While theories of second language socialisation and academic literacies recognize that important socialising interactions occur in social networks, classrooms continue to be the locus for much related research (Zappa-Hollman & Duff, 2015). In this thesis, I decentre the classroom and examine the language socialization of Japanese university students into English language academic writing practices through the lens of individual networks of practice (INoP). I studied the academic literacy socialisation accounts of English for Academic Purposes students over one Japanese academic year, investigating their individual networks, literacy practices and identities. The research is aligned with transdisciplinary SLA in which language learning/socialisation is seen as a constant interaction of micro, meso and macro levels (Douglas Fir Group [DFG], 2016) I took an ethnographic/longitudinal approach. Of seven focal participants, three were interviewed 6-9 times over one academic year and four were interviewed four times over a half academic year. Focal-participant interviews were triangulated with written assignments, interview with key people in networks and other data. Transcripts were coded using combined inductive analysis (Duff, 2008) and accounts of social interactions were represented as individual networks of practice (Zappa-Hollman & Duff, 2015). Analysis is complemented with a membership categorisation analysis (Sacks, 1992; Stokoe, 2012) of interview accounts showing categorisations produced in interviews to represent “common-sense” assumptions about culture and society. Analysis shows that different responses to similar constraints influenced variable socialisation trajectories. Construction and identification in individual networks of practice (1) shaped and was shaped by socialisation opportunities at the micro level; (2) resulted in variable socialisation outcomes and transformation of these same networks at the meso; and (3) illustrated the pervasiveness of macro-level social and cultural structures at all levels. The research argues that attention to networks can bridge levels to demonstrate the multiple macro constraints, meso agency/identities and micro interactions that shape socialisation.
Four-derivative couplings and BPS dyons in heterotic CHL orbifolds
Creators: name: Bossard, Guillaume
name: Cosnier-Horeau, Charles
name: Pioline, Boris
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Three-dimensional string models with half-maximal supersymmetry are believed to be invariant under a large U-duality group which unifies the S and T dualities in four dimensions. We propose an exact, U-duality invariant formula for four-derivative scalar couplings of the form $F(Φ) (\nablaΦ)^4$ in a class of string vacua known as CHL $\mathbb{Z}_N$ heterotic orbifolds with $N$ prime, generalizing our previous work which dealt with the case of heterotic string on $T^6$. We derive the Ward identities that $F(Φ)$ must satisfy, and check that our formula obeys them. We analyze the weak coupling expansion of $F(Φ)$, and show that it reproduces the correct tree-level and one-loop contributions, plus an infinite series of non-perturbative contributions. Similarly, the large radius expansion reproduces the exact $F^4$ coupling in four dimensions, including both supersymmetric invariants, plus infinite series of instanton corrections from half-BPS dyons winding around the large circle, and from Taub-NUT instantons. The summation measure for dyonic instantons agrees with the helicity supertrace for half-BPS dyons in 4 dimensions in all charge sectors. In the process we clarify several subtleties about CHL models in $D=4$ and $D=3$, in particular we obtain the exact helicity supertraces for 1/2-BPS dyonic states in all duality orbits.
description: 42+19 pages; v3: references added, few misprints corrected, several clarifications in section 2.1 and 2.2
Interpretation of the newly observed $Ω_c^0$ resonances
Creators: name: Wang, Wei
name: Zhu, Rui-Lin
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We study the charmed and bottomed doubly strange baryons within the heavy-quark-light-diquark framework. The two strange quarks are assumed to lie in $S$ wave and thus their total spin is 1. We calculate the mass spectra of the $S$ and $P$ wave orbitally excited states and find the $Ω_c^0 (2695)$ and $Ω_c^0 (2770)$ fit well as the $S$ wave states of charmed doubly strange baryons. The five newly $Ω_c^0(X)$ resonances observed by the LHCb Collaboration, i.e. $Ω_c^0(3000)$, $Ω_c^0(3050)$, $Ω_c^0(3066)$, $Ω_c^0(3090)$, and $Ω_c^0(3119)$, can be interpreted as the $P$ wave orbitally excited states. In heavy quark effective theory, we analyze their decays into the $Ξ^+_c K^-$ and $Ξ_c'^+ K^-$, and point out that decays of the five P-wave $Ω_c^0$ states into the $Ξ_c^+ K^-$ and $Ξ_c'^+K^-$ are suppressed by either heavy quark symmetry or phase space. The narrowness of the five newly observed $Ω_c^0(X)$ states can then be naturally interpreted with heavy quark symmetry.
description: 6 pages and 2 tables; To be published in Phys.Rev.D
Fingerprint Presentation Attack Detection by Channel-wise Feature Denoising
Creators: name: Liu, Feng
name: Kong, Zhe
name: Liu, Haozhe
name: Zhang, Wentian
name: Shen, Linlin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Due to the diversity of attack materials, fingerprint recognition systems (AFRSs) are vulnerable to malicious attacks. It is thus important to propose effective fingerprint presentation attack detection (PAD) methods for the safety and reliability of AFRSs. However, current PAD methods often exhibit poor robustness under new attack types settings. This paper thus proposes a novel channel-wise feature denoising fingerprint PAD (CFD-PAD) method by handling the redundant noise information ignored in previous studies. The proposed method learns important features of fingerprint images by weighing the importance of each channel and identifying discriminative channels and "noise" channels. Then, the propagation of "noise" channels is suppressed in the feature map to reduce interference. Specifically, a PA-Adaptation loss is designed to constrain the feature distribution to make the feature distribution of live fingerprints more aggregate and that of spoof fingerprints more disperse. Experimental results evaluated on the LivDet 2017 dataset showed that the proposed CFD-PAD can achieve a 2.53% average classification error (ACE) and a 93.83% true detection rate when the false detection rate equals 1.0% (TDR@FDR=1%). Also, the proposed method markedly outperforms the best single-model-based methods in terms of ACE (2.53% vs. 4.56%) and TDR@FDR=1%(93.83% vs. 73.32%), which demonstrates its effectiveness. Although we have achieved a comparable result with the state-of-the-art multiple-model-based methods, there still is an increase in TDR@FDR=1% from 91.19% to 93.83%. In addition, the proposed model is simpler, lighter and more efficient and has achieved a 74.76% reduction in computation time compared with the state-of-the-art multiple-model-based method. The source code is available at https://github.com/kongzhecn/cfd-pad.
description: 15 pages, 8 figures, Accepted by TIFS
Theory of non-Markovian dynamics in resonance fluorescence spectrum
Creators: name: Kumar, Abhishek
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present a detailed theoretical study of non-Markovian dynamics in the fluorescence spectrum of a driven semiconductor quantum dot (QD), embedded in a cavity and coupled to a three-dimensional (3D) acoustic phonon reservoir. In particular, we investigate the effect of pure dephasing on one of the side-peaks of the Mollow-triplet spectrum, expressed in terms of the off-diagonal element of the reduced system operator. The QD is modeled as a two-level system with an excited state representing a single exciton, and ground state represents the absence of an exciton. Coupling to the radiative modes of the cavity is treated within usual Born-Markov approximation, whereas dot-phonon coupling is discussed within non-Markovian regime beyond Born approximation. Using an equation-of-motion technique, the dot-phonon coupling is solved exactly and found that the exact result coincides with that of obtained within Born approximation. Furthermore, a Markov approximation is carried out with respect to the phonon interaction and compared with the non- Markovian lineshape for different values of the phonon bath temperature. We have found that coupling to the phonons vanishes for a resonant pump laser. For a non-resonant pump, we have characterzied the effect of dot-laser detuning and temperature of the phonon bath on the lineshape. The sideband undergoes a distinct narrowing and aquires an asymmetric shape with increasing phonon bath temperature. We have explained this behavior using a dressed-state picture of the QD levels.
Loop-Quantum-Gravity Simplicity Constraint as Surface Defect in Complex Chern-Simons Theory
Creators: name: Han, Muxin
name: Huang, Zichang
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The simplicity constraint is studied in the context of 4d spinfoam models with cosmological constant. We find that the quantum simplicity constraint is realized as the 2d surface defect in SL(2,$\mathbb{C}$) Chern-Simons theory in the construction of spinfoam amplitudes. By this realization of simplicity constraint in Chern-Simons theory, we are able to construct the new spinfoam amplitude with cosmological constant for arbitrary simplicial complex (with many 4-simplices). The semiclassical asymptotics of the amplitude is shown to reproduce correctly the 4-dimensional Einstein-Regge action with cosmological constant term.
description: 16 pages, 3 figures, presentation improved
The electronic structure and magnetic phase transition of hexagonal FeSe thin films studied by photoemission spectroscopy
Creators: name: Tan, S. Y.
name: Wen, C. H. P.
name: Xia, M.
name: Jiang, J.
name: Song, Q.
name: Xie, B. P.
name: Lai, X. C.
name: Feng, D. L.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Hexagonal FeSe thin films were grown on SrTiO3 substrates and the temperature and thickness dependence of their electronic structures were studied. The hexagonal FeSe is found to be metallic and electron doped, whose Fermi surface consists of six elliptical electron pockets. With decreased temperature, parts of the bands shift downward to high binding energy while some bands shift upwards to EF. The shifts of these bands begin around 300 K and saturate at low temperature, indicating a magnetic phase transition temperature of about 300 K. With increased film thickness, the Fermi surface topology and band structure show no obvious change except some minor quantum size effect. Our paper reports the first electronic structure of hexagonal FeSe, and shows that the possible magnetic transition is driven by large scale electronic structure reconstruction.
description: 11 pages, 4 figures
Dielectric Haloscopes to Search for Axion Dark Matter: Theoretical Foundations
Creators: name: Millar, Alexander J.
name: Raffelt, Georg G.
name: Redondo, Javier
name: Steffen, Frank D.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Experiment (hep-ex)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: We study the underlying theory of dielectric haloscopes, a new way to detect dark matter axions. When an interface between different dielectric media is inside a magnetic field, the oscillating axion field acts as a source of electromagnetic waves, which emerge in both directions perpendicular to the surface. The emission rate can be boosted by multiple layers judiciously placed to achieve constructive interference and by a large transverse area. Starting from the axion-modified Maxwell equations, we calculate the efficiency of this new dielectric haloscope approach. This technique could potentially search the unexplored high-frequency range of 10--100 GHz (axion mass 40--400 $μ$eV), where traditional cavity resonators have difficulties reaching the required volume.
description: 71 pages, 34 figures; v2: minor changes, typo in (4.13) corrected, matches published version
Towards an Ontology of Sustainable Space Logistics
Creators: name: BEN HAMIDA, Sonia
name: RICHARD, Muriel
name: KNEIB, Jean-Paul
Publisher: name: Proceedings of the 8th European Conference for Aeronautics and Space Sciences. Madrid, Spain, 1-4 july 2019
Year: 2019
Subjects: DESIGN
SYSTEMS
MODEL-BASED APPROACH
AEROSPACE SYSTEMS

description: Logistics is defined as \"the management of the flow of things between the point of origin and the point of consumption in order to meet the requirements of customers or corporations\" [1]. While Space logistics is a new field of its own and, although many concepts can be inherited from current logistics practices, it requires the creation of a new set of technologies and competencies. Moreover, space is a unique and fragile resource that is why it is key to develop this ecosystem with a long-term and sustainable vision. This paper introduces the foundation for an ontology of Sustainable Space Logistics, by characterizing the logistics nodes, the resources to manage, and the space logistics activities.
Using photo-ionisation models to derive carbon and oxygen gas-phase abundances in the rest UV
Creators: name: Pérez-Montero, Enrique
name: Amorín, Ricardo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present a new method to derive oxygen and carbon abundances using the ultraviolet (UV) lines emitted by the gas-phase ionised by massive stars. The method is based on the comparison of the nebular emission-line ratios with those predicted by a large grid of photo-ionisation models. Given the large dispersion in the O/H - C/O plane, our method firstly fixes C/O using ratios of appropriate emission lines and, in a second step, calculates O/H and the ionisation parameter from carbon lines in the UV. We find abundances totally consistent with those provided by the direct method when we apply this method to a sample of objects with an empirical determination of the electron temperature using optical emission lines. The proposed methodology appears as a powerful tool for systematic studies of nebular abundances in star-forming galaxies at high redshift.
description: 7 pages, 4 figures. MNRAS in press (DOI: 10.1093/mnras/stx186). Modified to match the published version
A Chebyshev-Tau Spectral Method for Coupled Modes of Underwater Sound Propagation in Range-Dependent Ocean Environments
Creators: name: Tu, Houwang
name: Wang, Yongxian
name: Yang, Chunmei
name: Liu, Wei
name: Xiao, Wenbin
name: Wang, Xiaodong
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: The stepwise coupled-mode model is a classic approach for solving range-dependent sound propagation problems. Existing coupled-mode programs have disadvantages such as high computational cost, weak adaptability to complex ocean environments and numerical instability. In this paper, a new algorithm is designed that uses an improved range normalization and global matrix approach to address range dependence in ocean environments. Due to its high accuracy in solving differential equations, the spectral method has recently been applied to range-independent normal modes and has achieved remarkable results. This algorithm uses the Chebyshev--Tau spectral method to solve for the eigenmodes in the range-independent segments. The main steps of the algorithm are parallelized, so OpenMP multithreading technology is also applied for further acceleration. Based on this algorithm, an efficient program is developed, and numerical simulations verify that this algorithm is reliable, accurate and capable. Compared with the existing coupled-mode programs, the newly developed program is more stable and efficient at comparable accuracies and can solve waveguides in more complex and realistic ocean environments.
description: 49 pages, 12 figures
Error-mitigated deep-circuit quantum simulation of open systems: steady state and relaxation rate problems
Creators: name: Wang, Anbang
name: Zhang, Jingning
name: Li, Ying
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Deep-circuit quantum computation, like Shor's algorithm, is undermined by error accumulation, and near-future quantum techniques are far from adequate for full-fledged quantum error correction. Instead of resorting to shallow-circuit quantum algorithms, recent theoretical research suggests that digital quantum simulation (DQS) of closed quantum systems are robust against the accumulation of Trotter errors, as long as local observables are concerned. In this paper, we investigate digital quantum simulation of open quantum systems. First, we prove that the deviation in the steady state obtained from digital quantum simulation depends only on the error in a single Trotter step, which indicates that error accumulation may not be disastrous. By numerical simulation of the quantum circuits for the DQS of the dissipative XYZ model, we then show that the correct results can be recovered by quantum error mitigation as long as the error rate in the DQS is below a sharp threshold. We explain this threshold behavior by the existence of a dissipation-driven quantum phase transition. Finally, we propose a new error-mitigation technique based on the scaling behavior in the vicinity of the critical point of a quantum phase transition. Our results expand the territory of near-future available quantum algorithms and stimulate further theoretical and experimental efforts in practical quantum applications.
„Zweite Welle“?
Creators: name: Wendt, Björn
name: Böschen, Stefan
name: Barth, Thomas
name: Henkel, Anna
name: Block, Katharina
name: Dickel, Sascha
name: Görgen, Benjamin
name: Köhrsen, Jens
name: Pfister, Thomas
name: Rödder, Simone
name: Schloßberger, Matthias
Publisher: name: Soziologie und Nachhaltigkeit
Year: 2018

description: Das politische Leitbild Nachhaltiger Entwicklung mit seiner integralen Verknüpfung von globalen ökologischen und sozialen Problemlagen und der darin liegenden Vision ihrer Lösung, stiftete für eine Soziologie der Nachhaltigkeit nicht nur den Anlass, sondern zugleich eine dezidierte normative Orientierung. Inzwischen beobachten wir allerdings eine Veralltäglichung und Pluralisierung von Nachhaltigkeit, sodass nicht mehr umstandslos die Gültigkeit einer geteilten normativen Prämisse voraussetzt werden kann. Die von K.-W. Brand ins Gespräch gebrachte Kennzeichnung einer „zweiten Welle“ soziologischer Nachhaltigkeitsforschung greifen wir auf, ohne aber die Normativität des Brundtland’schen Nachhaltigkeitsbegriffs als Prämisse zu setzen, sondern um für die schon in der „ersten Welle“ aufscheinende Reflexivität als Integrationspunkt zu argumentieren. Zur Untersuchung von Nachhaltigkeitsphänomenen stellen wir eine entsprechende Heuristik vor. Gewendet als Forschungsprogramm kann dies den Kern einer von Brand in den Raum gestellten „zweiten Welle“ der Soziologie der Nachhaltigkeit darstellen. The political concept of sustainable development is built on the idea of an integral solution of global ecological as well as social problems. The underlying vision of their possible solution not only brought about a window of opportunity for creating a sociology of sustainability, but also offered a clear normative orientation for this field of investigation. In the meantime, we are observing a routinization and pluralization of sustainability practices. Thus, a shared normative premise can no longer be presupposed. We pick up the idea of a “second wave“ of sociological sustainability research, which was coined by K.-W. Brand, but without setting the normativity of the Brundtland’s conception of sustainability as the premise. Doing so, we argue for reflexivity, already apparent in the “first wave”, as an integration point in the “second wave”. To investigate sustainability phenomena we present a heuristic. Applied as a research program, this can be the core of a “second wave“ of the sociology of sustainability as suggested by Brand.
description: Soziologie und Nachhaltigkeit, Sonderband 1: Soziologie der Nachhaltigkeit
The XXL Survey XVIII. ATCA 2.1 GHz radio source catalogue and source counts for the XXL-South field
Creators: name: Butler, Andrew
name: Huynh, Minh
name: Delhaize, Jacinta
name: Smolčić, Vernesa
name: Kapińska, Anna
name: Milaković, Dinko
name: Novak, Mladen
name: Baran, Nikola
name: O'Brien, Andrew
name: Chiappetti, Lucio
name: Desai, Shantanu
name: Fotopoulou, Sotiria
name: Horellou, Cathy
name: Lidman, Chris
name: Pierre, Marguerite
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The 2.1 GHz radio source catalogue of the 25 deg$^2$ ultimate XMM extragalactic survey south (XXL-S) field, observed with the Australia Telescope Compact Array (ATCA), is presented. The final radio mosaic achieved a resolution of $\sim$$4.8"$ and a median rms noise of $σ\approx41$ $μ$Jy/beam. To date, this is the largest area radio survey to reach this flux density level. A total of 6350 radio components above 5$σ$ are included in the component catalogue, 26.4% of which are resolved. Of these components, 111 were merged together to create 48 multiple-component radio sources, resulting in a total of 6287 radio sources in the source catalogue, 25.9% of which were resolved. A survival analysis revealed that the median spectral index of the Sydney University Molonglo Sky Survey (SUMSS) 843 MHz sources in the field is $α$ = $-$0.75, consistent with the values of $-0.7$ to $-0.8$ commonly used to characterise radio spectral energy distributions of active galactic nuclei (AGN). The 2.1 GHz and 1.4 GHz differential radio source counts are presented and compared to other 1.4 GHz radio surveys. The XXL-S source counts show good agreement with the other surveys.
description: 19 pages, 19 figures. Accepted for publication in A&A
title: Optical flow models as an open benchmark for radar-based precipitation nowcasting (rainymotion v0.1)
Creators: name: Ayzel, Georgy
name: Heistermann, Maik
name: Winterrath, Tanja
Publisher: name: Universität Potsdam
Year: 2019

description: Quantitative precipitation nowcasting (QPN) has become an essential technique in various application contexts, such as early warning or urban sewage control. A common heuristic prediction approach is to track the motion of precipitation features from a sequence of weather radar images and then to displace the precipitation field to the imminent future (minutes to hours) based on that motion, assuming that the intensity of the features remains constant (“Lagrangian persistence”). In that context, “optical flow” has become one of the most popular tracking techniques. Yet the present landscape of computational QPN models still struggles with producing open software implementations. Focusing on this gap, we have developed and extensively benchmarked a stack of models based on different optical flow algorithms for the tracking step and a set of parsimonious extrapolation procedures based on image warping and advection. We demonstrate that these models provide skillful predictions comparable with or even superior to state-of-the-art operational software. Our software library (“rainymotion”) for precipitation nowcasting is written in the Python programming language and openly available at GitHub (https://github.com/hydrogo/rainymotion, Ayzel et al., 2019). That way, the library may serve as a tool for providing fast, free, and transparent solutions that could serve as a benchmark for further model development and hypothesis testing – a benchmark that is far more advanced than the conventional benchmark of Eulerian persistence commonly used in QPN verification experiments.
description: Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe, 709