cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Electronic structure and signature of Tomonaga-Luttinger liquid state in epitaxial CoSb$_{1-x}$ nanoribbons
Creators: name: Lou, Rui
name: Lei, Minyinan
name: Ding, Wenjun
name: Yang, Wentao
name: Chen, Xiaoyang
name: Tao, Ran
name: Ding, Shuyue
name: Shen, Xiaoping
name: Yan, Yajun
name: Cui, Ping
name: Xu, Haichao
name: Peng, Rui
name: Zhang, Tong
name: Zhang, Zhenyu
name: Feng, Donglai
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Recently, monolayer CoSb/SrTiO$_3$ has been proposed as a candidate harboring interfacial superconductivity in analogy with monolayer FeSe/SrTiO$_3$. Experimentally, while the CoSb-based compounds manifesting as nanowires and thin films have been realized on SrTiO$_3$ substrates, serving as a rich playground, their electronic structures are still unknown and yet to be resolved. Here, we have fabricated CoSb$_{1-x}$ nanoribbons with quasi-one-dimensional stripes on SrTiO$_3$(001) substrates using molecular beam epitaxy, and investigated the electronic structure by in situ angle-resolved photoemission spectroscopy. Straight Fermi surfaces without lateral dispersions are observed. CoSb$_{1-x}$/SrTiO$_3$ is slightly hole doped, where the interfacial charge transfer is opposite to that in monolayer FeSe/SrTiO$_3$. The spectral weight near Fermi level exhibits power-law-like suppression and obeys a universal temperature scaling, serving as the signature of Tomonaga-Luttinger liquid (TLL) state. The obtained TLL parameter of $\sim$0.21 shows the underlying strong correlations. Our results not only suggest CoSb$_{1-x}$ nanoribbon as a representative TLL system, but also provide clues for further investigations on the CoSb-related interface.
description: 27 pages, 3 figures
Electronic reconstruction and charge transfer in strained Sr$_2$CoIrO$_6$ double perovskite
Creators: name: Wu, Jiongyao
name: Ney, Marcel
name: Esser, Sebastian
name: Begum, Vijaya
name: Prinz, Günther
name: Lorke, Axel
name: Gegenwart, Philipp
name: Pentcheva, Rossitza
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The electronic, magnetic and optical properties of the double perovskite Sr$_2$CoIrO$_6$ (SCIO) under biaxial strain are explored in the framework of density functional theory (DFT) including a Hubbard $U$ term and spin-orbit coupling (SOC) in combination with absorption spectroscopy measurements on epitaxial thin films. While the end member SrIrO$_3$ is a semimetal with a quenched spin and orbital moment and bulk SrCoO$_3$ is a ferromagnetic (FM) metal with spin and orbital moment of 2.50 and 0.13 $μ_{B}$, respectively, the double perovskite SCIO emerges as an antiferromagnetic Mott insulator with antiparallel alignment of Co, Ir planes along the [110]-direction. Co exhibits a spin and enhanced orbital moment of $\sim 2.35-2.45$ and $0.31-$0.45 $μ_{B}$, respectively. Most remarkably, Ir acquires a significant spin and orbital moment of 1.21-1.25 and 0.13 $μ_{B}$, respectively. Analysis of the orbital occupation indicates an electronic reconstruction due to a substantial charge transfer from minority to majority spin states in Ir and from Ir to Co, signaling an Ir$^{4+δ}$, Co$^{4-δ}$ configuration. Biaxial strain, varied from -1.02% ($a_{\rm NdGaO_3}$) through 0% ($a_{\rm SrTiO_3}$) to 1.53% ($a_{\rm GdScO_3}$), influences in partcular the orbital polarization of the $t_{2g}$ states and leads to a nonmonotonic change of the band gap between 163 and 235 meV. The absorption coefficient reveals a two plateau fearure due to transitions from the valence to the lower lying narrow $t_{2g}$ and the higher lying broader $e_{g}$ bands. Inclusion of many body effects, in particular, excitonic effects by solving the Bethe-Salpeter equation (BSE), increases the band gap by $\sim0.2$ and improves the agreement with the measured spectrum concerning the position of the second peak at $\sim 2.6$ eV.
description: 11 pages, 10 figures
Gravitational intraction on quantum level and consequences thereof
Creators: name: Fisenko, S. I.
name: Fisenko, I. S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: The notion of gravitational emission as an emission of the same level with electromagnetic emission is based on the proven fact of existence of electrons stationary states in its own gravitational field, characterized by gravitational constant
description: 22 pages, 9 figures
Reasonable non--Radon--Nikodym ideals
Creators: name: Kanovei, Vladimir
name: Lyubetsky, Vassily
Publisher: name: arXiv
Year: 2008
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03E15

description: For any abelian Polish sigma-compact group H there exist a sigma-ideal Z over N and a Borel Z-approximate homomorphism f : H --> H^N which is not Z-approximable by a continuous true homomorphism g : H --> H^N.
A Digital Twin Design Methodology for Control, Simulation, and Monitoring of Fluidic Circuits
Creators: name: Gunes, Veyis
Publisher: name: arXiv
Year: 2024
Subjects: subject: Systems and Control (eess.SY)
subject: Emerging Technologies (cs.ET)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: We propose a synthesis method for the design of digital twins applicable to various systems (pneumatic, hydraulic, electrical/electronic circuits). The methodology allows representing the operation of these systems through an active digital twin, thereby enabling a more suitable and easier computer-aided design, simulation, control, and monitoring. Furthermore, our methodology enables the detection of a system's actions on its own inputs (for example, in pneumatics: backflow of gases trapped in part of a fluidic system onto its own inputs). During the simulation or monitoring phase, the approach also facilitates real-time diagnosis of the controlled system. The outputs, on the controlled physical system or its digital twin, do not depend only on the current inputs but also on the history of the inputs and the history of internal states and variables. In other words, the underlying sequential logic has a memory while an only combinational logic approach does not. These capabilities can contribute to the digital transformation of the factory of the future.
description: 9 pages, 6 figures
„Halbmedienkompetenz?“ – Überlegungen zur kritischen Dimension von Medienkompetenz
Creators: name: Damberger, Thomas
Publisher: name: Medienimpulse
Year: 2013

description: Der folgende Beitrag befasst sich mit der Mehrdimensionalität und der Normativität des Medienkompetenzbegriffs. Dabei wird deutlich, dass Medienkompetenz im pädagogischen Sinne gerade auf die kritische Dimension nicht verzichten kann. Diese Unverzichtbarkeit wird epistemologisch im Rückgriff auf Schopenhauer, Humboldt und Kant hergeleitet.
description: Medienimpulse, Bd. 51 Nr. 1 (2013): 1/2013 - Normen und Normierungen
Quantitative isoperimetric inequalities for classical capillarity problems
Creators: name: Pascale, Giulio
name: Pozzetta, Marco
Publisher: name: arXiv
Year: 2024
Subjects: subject: Analysis of PDEs (math.AP)
subject: Differential Geometry (math.DG)
subject: Optimization and Control (math.OC)
subject: FOS: Mathematics

description: We consider capillarity functionals which measure the perimeter of sets contained in a Euclidean half-space assigning a constant weight $λ\in (-1,1)$ to the portion of the boundary that touches the boundary of the half-space. Depending on $λ$, sets that minimize this capillarity perimeter among those with fixed volume are known to be suitable truncated balls lying on the boundary of the half-space.
 We first give a new proof based on an ABP-type technique of the sharp isoperimetric inequality for this class of capillarity problems. Next we prove two quantitative versions of the inequality: a first sharp inequality estimates the Fraenkel asymmetry of a competitor with respect to the optimal bubbles in terms of the energy deficit; a second inequality estimates a notion of asymmetry for the part of the boundary of a competitor that touches the boundary of the half-space in terms of the energy deficit.
 After a symmetrization procedure, the quantitative inequalities follow from a novel combination of a quantitative ABP method with a selection-type argument.
A persistent double nuclear structure in 3C 84
Creators: name: Oh, Junghwan
name: Hodgson, Jeffrey A.
name: Trippe, Sascha
name: Krichbaum, Thomas P.
name: Kam, Minchul
name: Paraschos, Georgios Filippos
name: Kim, Jae-Young
name: Rani, Bindu
name: Sohn, Bong Won
name: Lee, Sang-Sung
name: Lico, Rocco
name: Liuzzo, Elisabetta
name: Bremer, Michael
name: Zensus, Anton
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: 3C 84 (NGC 1275) is the radio source at the center of the Perseus Cluster and exhibits a bright radio jet. We observed the source with the Global Millimeter VLBI Array (GMVA) between 2008 and 2015, with a typical angular resolution of $\sim$50 $μ$as. The observations revealed a consistent double nuclear structure separated by $\sim$770 gravitational radii assuming a Black Hole mass of 3.2 $\times 10^{8}$ $M_{\odot}$. The region is likely too broad and bright to be the true jet base anchored in the accretion disk or Black Hole ergosphere. A cone and parabola were fit to the stacked (time averaged) image of the nuclear region. The data did not strongly prefer either fit, but combined with a jet/counter-jet ratio analysis, an upper limit on the viewing angle to the inner jet region of $\leq$35$^{\circ}$ was found. This provides evidence for a variation of the viewing angle along the jet (and therefore a bent jet) within $\sim$0.5 parsec of the jet launching region. In the case of a conical jet, the apex is located $\sim$2400 gravitational radii upstream of the bright nuclear region and up to $\sim$600 gravitational radii upstream in the parabolic case. We found a possible correlation between the brightness temperature and relative position angle of the double nuclear components, which may indicate rotation within the jet.
The Discovery of Stellar Oscillations in the K Giant $ι$ Dra
Creators: name: Zechmeister, Mathias
name: Reffert, Sabine
name: Hatzes, Artie P.
name: Endl, Michael
name: Quirrenbach, Andreas
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: $ι$ Dra (HIP 75458) is a well-known example for a K giant hosting a substellar companion since its discovery by Frink et al. (2002). We present radial velocity measurements of this star from observations taken with three different instruments spanning nearly 8 years. They show more clearly that the RV period is long-lived and coherent thus supporting the companion hypothesis. The longer time baseline now allows for a more accurate determination of the orbit with a revised period of P=511 d and an additional small linear trend, indicative of another companion in a wide orbit. Moreover we show that the star exhibits low amplitude, solar like oscillations with frequencies around 3-4 d$^{-1}$ (34.7-46.3 $μ$Hz).
description: 6 pages, 6 figures, 4 tables, accepted by A&A
Privatheit – Privatsphäre: Normative Konzepte im Wandel
Creators: name: Trültzsch-Wijnen, Sascha
name: Pscheida, Daniela
Publisher: name: Medienimpulse
Year: 2014

description: Im Zusammenhang mit der Nutzung von Social Networks Sites wie Facebook ist von Exhibitionismus und einer Kultur der Freizügigkeit die Rede. Aber geben die NutzerInnen wirklich ihre Privatsphäre auf? Ist das öffentliche Ausbreiten privater Lebensbereiche wirklich originär neu? Welche medienhistorischen und sozialphilosophischen Traditionen finden sich? Dieser Artikel untersucht (historisch) normative Konzepte der Privatheit.
description: Medienimpulse, Bd. 51 Nr. 1 (2013): 1/2013 - Normen und Normierungen
Graphene's non-equilibrium fermions reveal Doppler-shifted magnetophonon resonances accompanied by Mach supersonic and Landau velocity effects
Creators: name: Greenaway, M. T.
name: Kumaravadivel, P.
name: Wengraf, J.
name: Ponomarenko, L. A.
name: Li, A. I. Berdyugin. J.
name: Edgar, J. H.
name: Kumar, R. Krishna
name: Geim, A. K.
name: Eaves, L.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Oscillatory magnetoresistance measurements on graphene have revealed a wealth of novel physics. These phenomena are typically studied at low currents. At high currents, electrons are driven far from equilibrium with the atomic lattice vibrations so that their kinetic energy can exceed the thermal energy of the phonons. Here, we report three non-equilibrium phenomena in monolayer graphene at high currents: (i) a "Doppler-like" shift and splitting of the frequencies of the transverse acoustic (TA) phonons emitted when the electrons undergo inter-Landau level (LL) transitions; (ii) an intra-LL Mach effect with the emission of TA phonons when the electrons approach supersonic speed, and (iii) the onset of elastic inter-LL transitions at a critical carrier drift velocity, analogous to the superfluid Landau velocity. All three quantum phenomena can be unified in a single resonance equation. They offer avenues for research on out-of-equilibrium phenomena in other two-dimensional fermion systems.
Mixed Columnar-Plaquette Crystal of correlated fermions on the 2D pyrochlore lattice at fractional filling
Creators: name: Trousselet, F.
name: Poilblanc, D.
name: Moessner, R.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study a model of strongly correlated S=1/2 fermions on the planar pyrochlore, or checkerboard, lattice, at fractional (1/8) filling. Starting with the extended Hubbard model in the limit of strong Coulomb repulsion, low-energy configurations can be mapped onto hard-core dimer configurations whose dimers carry a spin degree of freedom. An effective Hamiltonian similar to the kinetic term of a quantum dimer model on the square lattice which rotates two parallel dimers (in a spin-singlet configuration) by 90 degrees naturally emerges. We also introduce an additional term in the Hamiltonian, a generalized dimer plaquette interaction, in order to realize a closer analogy to the latter model. For a strong dimer plaquette attraction stabilizing a columnar phase, a spontaneous dimerization takes place in the direction of the columns of (spin-carrying) dimers. Using exact diagonalizations of two-dimensional periodic clusters, the analysis of the low-energy spectrum and of several types of correlation functions gives indeed evidence for a new type of lattice symmetry breaking phase, the eight-fold degenerate Mixed Columnar-Plaquette Crystal, and for a transition from this phase to a Resonating-Singlet-Pair Crystal (found in previous studies) which restores the rotational symmetry of the lattice. Similar conclusions and phase diagram are also reached from a simple variational approach.
description: 14 pages, 15 figures
On the structure of the set of bifurcation points of periodic solutions for multiparameter Hamiltonian systems
Creators: name: Radzki, Wiktor
Publisher: name: arXiv
Year: 2008
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 34C23, 34C25 (Primary) 70H05, 70H12 (Secondary)

description: This paper deals with periodic solutions of the Hamilton equation with many parameters. Theorems on global bifurcation of solutions with periods $2π/j,$ $j\in\mathbb{N},$ from a stationary point are proved. The Hessian matrix of the Hamiltonian at the stationary point can be singular. However, it is assumed that the local topological degree of the gradient of the Hamiltonian at the stationary point is nonzero. It is shown that (global) bifurcation points of solutions with given periods can be identified with zeros of appropriate continuous functions on the space of parameters. Explicit formulae for such functions are given in the case when the Hessian matrix of the Hamiltonian at the stationary point is block-diagonal. Symmetry breaking results concerning bifurcation of solutions with different minimal periods are obtained. A geometric description of the set of bifurcation points is given. Examples of constructive application of the theorems proved to analytical and numerical investigation and visualization of the set of all bifurcation points in given domain are provided. This paper is based on a part of the author's thesis [W. Radzki, ``Branching points of periodic solutions of autonomous Hamiltonian systems'' (Polish), PhD thesis, Nicolaus Copernicus University, Faculty of Mathematics and Computer Science, Toruń, 2005].
description: 35 pages, 4 figures, PDFLaTeX
Die Projekte der M2
Creators: name: Schreger, Christian
Publisher: name: Medienimpulse
Year: 2014

description: In der M2 an der VS Ortnergasse sind in den letzten 15 Jahren eine ganze Reihe erfolgreicher Projekte durchgeführt worden, die viele Auszeichnungen bis hin zum Multimedia Staatspreis-Förderpreis 2007 erhalten haben. Christian Schreger fasst die Aktivitäten der M2 in seinem Bericht zusammen.
description: Medienimpulse, Bd. 51 Nr. 1 (2013): 1/2013 - Normen und Normierungen
Dynamische Lieferzeit-Preisgestaltung in variantenreicher Produktion : Ein adaptiver Ansatz mithilfe von Reinforcement Learning
Creators: name: Stamer, Florian
Publisher: name: Shaker Verlag
Year: 2022
Subjects: Produktion
dynamische Preisgestaltung
Reinforcement Learning
Actor Critic
Simulation
variantenreiche Produktion

description: Das Wertschöpfungsnetzwerk ist heute zur dominierenden Wertschöpfungsstruktur im Bereich der Produktion geworden. Für produzierende Unternehmen in solchen Netzwerken ist das Auftragsmanagement eine zentrale Aufgabe, die sich in einem Umfeld wachsender Herausforderungen befindet. Zum einen setzen kürzere Produktlebenszyklen und zunehmende Individualisierung die Unternehmen unter Druck. In diesem Zusammenhang hat die variantenreiche Produktion an Bedeutung gewonnen. Andererseits steigen die Wahrscheinlichkeit und die Auswirkungen von Störungen, insbesondere in Netzwerken, was die Leistungsfähigkeit von Produktionssystemen herausfordert. Ein vielversprechender Ansatz in diesem Zusammenhang ist die Verwendung einer dynamischen Lieferzeit-Preisgestaltung über eine kontinuierliche Preis-Lieferzeit-Funktion. Durch den Einsatz einer dynamischen Lieferzeit-Preisgestaltung könnte es möglich sein, die Nachfrage im Netz mit den Fähigkeiten des Produktionssystems in Einklang zu bringen. Die Idee ist, Nachfragespitzen zu verschieben und die Kunden entsprechend ihrer individuellen Präferenzen zu beliefern. Auf diese Weise kann der Gesamtgewinn gesteigert werden, obwohl die Kapazitäten konstant bleiben. Um die aufgestellten Hypothesen zu untersuchen, wird in dieser Arbeit eine Methodik zur dynamischen Lieferzeit-Preisgestaltung für die variantenreiche Produktion entwickelt. In einem ersten Schritt werden Leistungskennzahlen und eine Zielfunktion festgelegt. In einem zweiten Schritt wird ein Actor Critic Reinforcement-Learning-Verfahren als Grundlage für ein Lösungsmodell motiviert. Für das Training und das spätere Testen des resultierenden Lernagenten wird ein Simulationsmodell als Umgebung entwickelt und ein Verfahren zur Durchführung und Auswertung der Experimente ausgearbeitet. Der Ansatz wurde im Rahmen der BMBF-Forschungsprojekte ReKoNeT und BaSys4SupplyQ diskutiert und angewendet. Die Ergebnisse aus zwei Anwendungsfällen zeigen, dass der Ansatz in der Lage ist, bei gleicher Kapazität deutlich höhere Gewinne zu erzielen und Nachfragespitzen in gewissem Umfang zu glätten. Gleichzeitig zeigen die Ergebnisse, dass das Einsparen von Kapazitäten keine dominante Strategie zu sein scheint. Dies spiegelt die anwendungsspezifische Berücksichtigung verschiedener Ziele wie Service, Kapazitätskosten und Marge wider.
Control of state and state entanglement with a single auxiliary subsystem
Creators: name: Rossi, R.
name: de Magalhães, A. R. Bosco
name: de Faria, J. G. Peixoto
name: Nemes, M. C.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present a strategy to control the evolution of a quantum system. The novel aspect of this protocol is the use of a \emph{single auxiliary subsystem}. Two applications are given, one which allows for state preservation and another which controls the degree of entanglement of a given initial state.
Temporal Extent of Surface Potentials between Closely Spaced Metals
Creators: name: Pollack, Scott E
name: Schlamminger, Stephan
name: Gundlach, Jens
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: Variations in the electrostatic surface potential between the proof mass and electrode housing in the space-based gravitational wave mission LISA is one of the largest contributors of noise at frequencies below a few mHz. Torsion balances provide an ideal testbed for investigating these effects in conditions emulative of LISA. Our apparatus consists of a Au coated Cu plate brought near a Au coated Si plate pendulum suspended from a thin W wire. We have measured a white noise level of $30, \uVhz$ above approximately 0.1, mHz, rising at lower frequencies, for the surface potential variations between these two closely spaced metals.
Vub extraction using the Analytic Coupling model
Creators: name: Aglietti, U.
name: Di Lodovico, F.
name: Ferrera, G.
name: Ricciardi, G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We summarize the main characteristics and recent results on B->Xulnu decays of a model based on soft-gluon resummation and an analytic time-like QCD coupling.
description: To appear in proceedings of Second Workshop on Theory, Phenomenology and Experiments in Heavy Flavor Physics, Capri, Italy, 16-18 June 2008
Soliton modes, stability, and drift in optical lattices with spatially modulated nonlinearity
Creators: name: Kartashov, Yaroslav V.
name: Vysloukh, Victor A.
name: Torner, Lluis
Publisher: name: arXiv
Year: 2008
Subjects: subject: Optics (physics.optics)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We put forward new properties of lattice solitons in materials and geometries where both, the linear refractive index and the nonlinearity are spatially modulated. We show that the interplay between linear and out-of-phase nonlinear refractive index modulations results in new soliton properties, including modifications of the soliton stability and transverse mobility, as well as shape transformations that may be controlled, e.g., by varying the light intensity.
description: 12 pages, 4 figures, to appear in Optics Letters
The Kodaira Dimension of Lefschetz Fibrations
Creators: name: Dorfmeister, Josef G
name: Zhang, Weiyi
Publisher: name: arXiv
Year: 2008
Subjects: subject: Symplectic Geometry (math.SG)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: In this note, we verify that the complex Kodaira dimension $κ^h$ equals the symplectic Kodaira dimension $κ^s$ for smooth 4-manifolds with complex and symplectic structures. We also calculate the Kodaira dimension for many Lefschetz fibrations.
description: 20 pages, corrected typos and included suggestions made by the referees. To appear in Asian J. of Mathematics
A comunicação e a busca de informação no processo científico
Creators: name: , Santana
Publisher: name: Zenodo
Year: 2020
Subjects: comunicação científica
recuperação da informação
processo científico

description: Palestra com o tema "A comunicação e a busca de informação no processo científico" proferida pelo Bibliotecário Anderson de Santana (https://orcid.org/0000-0002-9222-6431), Chefe Técnico do Serviço de Biblioteca do Instituto de Geociências da USP como parte das atividades da disciplina "0440102 – Metodologia Científica em Geociências" sob responsabilidade do Prof. Dr. Valdecir de Assis Janasi (http://lattes.cnpq.br/2249074352821232).
description: Apresentação em vídeo disponível em: https://youtu.be/PlrHNnVd8lc
The Magnetic Eden Model
Creators: name: Candia, Julián
name: Albano, Ezequiel V.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In the magnetic Eden model (MEM), particles have a spin and grow in contact with a thermal bath. Although Ising-like interactions affect the growth dynamics, deposited spins are frozen and not allowed to flip. This review article focuses on recent developments and future prospects, such as spontaneous switching phenomena, critical behavior associated with fractal, wetting, and order-disorder phase transitions, the equilibrium/nonequilibrium correspondence conjecture, as well as dynamical and critical features of the MEM defined on complex network substrates.
description: 22 pages, 9 figures. To appear in IJMPC
Chiral domain wall dynamics in magnetic heterostructures with bulk Dzyaloshinskii-Moriya interactions
Creators: name: Li, Mei
name: Xi, Bin
name: Lu, Jie
name: Liu, Yongjun
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: In this work, dynamics of chiral domain walls in long and narrow magnetic heterostructures based on non-centrosymmetric chiral magnets with bulk Dzyaloshinskii-Moriya interactions (DMI) and perpendicular magnetic anisotropy is systematically investigated. The driving forces can be out-of-plane magnetic fields and in-plane currents, correspondingly both steady and precessional flows are considered. Their dividing points (the Walker critical field and current density) are obtained as functions of bulk DMI strength ($D_{\mathrm{b}}$) and the ratio ($κ$) of total (crystalline plus shape) anisotropy in the hard axis over that in the easy one. When far beyond Walker breakdown, the dependence curve of wall velocity on external in-plane bias field takes parabolic shape around the compensation point where the total in-plane field disappears. The center shift is determined by $D_{\mathrm{b}}$, $κ$, and the wall's topological charge, thus can be used to measure the bulk DMI strength in chiral magnets.
description: 9 pages, 4 figures
Surface gravity in spherically symmetric collapsing stars
Creators: name: Sadeghi, A.
name: Shojai, F.
name: Bahmani, F.
Publisher: name: arXiv
Year: 2024
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Here we consider the generalized Oppenheimer-Snyder collapse of a star into a four-dimensional Einstein-Gauss-Bonnet black hole as well as a class of regular black holes labeled by the polytropic index of the stellar matter. We then analyze the nature of the horizon and the corresponding surface gravity outside and inside the star. The Hayward and Nielsen-Visser dynamical surface gravity are in agreement with the one resulting from the Killing vector of the outer static metric. However, these two definitions inside the star do not coincide with the Killing surface gravity outside the star when the star crosses the event horizon. This motivates us to study the surface gravity using Fodor's approach to have a unique surface gravity at the mentioned moment. Then the extremality condition and the first law of thermodynamics are discussed at the trapping horizon of the star.
description: 13 pages, 2 figures, accepted for publication in EPJC
Magnetocentrifugally Driven Flows from Young Stars and Disks. VI. Accretion with a Multipole Stellar Field
Creators: name: Mohanty, Subhanjoy
name: Shu, Frank H.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Previous analyses of magnetospheric accretion and outflow in classical T Tauri stars (CTTSs), within the context of both the X-wind model and other theoretical scenarios, have assumed a dipolar geometry for the stellar magnetic field if it were not perturbed by the presence of an accreting, electrically conducting disk. However, CTTS surveys reveal that accretion hot spots cover a small fraction of the stellar surface, and that the net field polarization on the stellar surface is small. Both facts imply that the magnetic field generated by the star has a complex non-dipolar structure. To address this discrepancy between theory and observations, we re-examine X-wind theory without the dipole constraint. Using simple physical arguments based on the concept of trapped flux, we show that a dipole configuration is in fact not essential. Independent of the precise geometry of the stellar magnetosphere, the requirement for a certain level of trapped flux predicts a definite relationship among various CTTS observables. Moreover, superposition of multipole stellar fields naturally yield small observed hot-spot covering fractions and small net surface polarizations. The generalized X-wind picture remains viable under these conditions, with the outflow from a small annulus near the inner disk edge little affected by the modified geometry, but with inflow highly dependent on the details of how the emergent stellar flux is linked and trapped by the inner disk regions. Our model is consistent with data, including recent spectropolarimetric measurements of the hot spot sizes and field strengths in V2129 Oph and BP Tau.
description: ApJ accepted; 47 pages (submission format), 7 figures
Learning Interpretable Concept Groups in CNNs
Creators: name: Varshneya, Saurabh
name: Ledent, Antoine
name: Vandermeulen, Robert A.
name: Lei, Yunwen
name: Enders, Matthias
name: Borth, Damian
name: Kloft, Marius
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We propose a novel training methodology -- Concept Group Learning (CGL) -- that encourages training of interpretable CNN filters by partitioning filters in each layer into concept groups, each of which is trained to learn a single visual concept. We achieve this through a novel regularization strategy that forces filters in the same group to be active in similar image regions for a given layer. We additionally use a regularizer to encourage a sparse weighting of the concept groups in each layer so that a few concept groups can have greater importance than others. We quantitatively evaluate CGL's model interpretability using standard interpretability evaluation techniques and find that our method increases interpretability scores in most cases. Qualitatively we compare the image regions that are most active under filters learned using CGL versus filters learned without CGL and find that CGL activation regions more strongly concentrate around semantically relevant features.
Bericht zur Tagung „Normativität und Normative (in) der Pädagogik“ an der Universität Wien, 01.–02.11.2012
Creators: name: Fuchs, Thorsten
Publisher: name: Medienimpulse
Year: 2015

description: Welchen Status hat Normativität in der Pädagogik? Ist Normativität möglich und notwendig; welche Leistung kommt ihr allgemein im Gegenstandsfeld der Pädagogik und in den verschiedenen pädagogischen Diskussionszusammenhängen eigentlich zu? Diese zwar keineswegs neuen, aber nach wie vor akuten und an Brisanz in den letzten Jahren eher noch gewonnenen Generalfragen waren Thema der wissenschaftlichen Tagung, die am 01. und 02. November 2012 am Institut für Bildungswissenschaft der Universität Wien stattfand.
description: Medienimpulse, Bd. 51 Nr. 1 (2013): 1/2013 - Normen und Normierungen
Model-independent inference of quantum interaction from statistics
Creators: name: Sarkar, Shubhayan
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Any physical theory aims to establish the relationship between physical systems in terms of the interaction between these systems. However, any known approach in the literature to infer this interaction is dependent on the particular modelling of the physical systems involved. Here, we propose an alternative approach where one does not need to model the systems involved but only assume that these systems behave according to quantum theory. We first propose a setup to infer a particular entangling quantum interaction between two systems from the statistics. For our purpose, we utilise the framework of Bell inequalities. We then extend this setup where an arbitrary number of quantum systems interact via some entangling interaction.
description: 6+11 pages. Comments are welcome:)
DRAGON: Monte Carlo generator of particle production from a fragmented fireball in ultrarelativistic nuclear collisions
Creators: name: Tomasik, Boris
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: A Monte Carlo generator of the final state of hadrons emitted from an ultrarelativistic nuclear collision is introduced. An important feature of the generator is a possible fragmentation of the fireball and emission of the hadrons from fragments. Phase space distribution of the fragments is based on the blast wave model extended to azimuthally non-symmetric fireballs. Parameters of the model can be tuned and this allows to generate final states from various kinds of fireballs. A facultative output in the OSCAR1999A format allows for a comprehensive analysis of phase-space distributions and/or use as an input for an afterburner.
description: name of the model changed from QuaG to DRAGON in the new version, otherwise only cosmetic changes, uses elsart.cls, the software package described here can be downloaded from http://www.fpv.umb.sk/~tomasik/soft.html
Aktivistische Brieftauben
Creators: name: Sützl, Wolfgang
Publisher: name: Medienimpulse
Year: 2014

description: Im biopolitischen Medienaktivismus sind eine Vielzahl von Interventionen gegen die Dispositive der Foucaultschen Biomacht entstanden. Wolfgang Sützl untersucht Widerstandsformen, die biopolitische Strategien gleichzeitig unterwandern und einsetzen. Im Rekurs auf Walter Benjamins Theorie des Autors als Produzent hebt Sützl die Möglichkeit hervor, diese auf die digitale Kultur- und Technikproduktion zu beziehen. Auch ist damit eine postfordistische Theorie des biopolitischen Kognitariats verbunden, auf dessen lebendige Ressourcen die Biomacht zugreift, um Wissen („Human Capital“) als Mehrwert abzusaugen. Im Widerstand dazu können aber aktivistische Tauben und Tulpen eingesetzt werden um subversive Kräfte in Gang zu setzen.
description: Medienimpulse, Bd. 50 Nr. 2 (2012): 2/2012 - Biomacht, Biopolitik, Biomedien
Zur Tiefengrammatik des "Lebendigen"
Creators: name: Mueller, Martin
Publisher: name: Medienimpulse
Year: 2014

description: Martin Müller untersucht eingehend die Rolle der technischen und medialen Dimensionen der Lebenswissenschaften und führt so anhand von Eugene Thackers Begriff der Biomedien vor Augen, dass auch Dinge und Materialitäten handlungstheoretisch gefasst werden können. Dabei werden Technologien wie etwa Online-Gendatenbanken, Gen-Synthesizer, DNA-Computer, molekulare Speicher und Proteinchips diskutiert. Biomedien erscheinen dabei als Medienkonstellationen, in denen sich das „Leben selbst“ auf andere, vielleicht neue Weise zu vermitteln und zu zeigen vermag. Biomedien, so hält der Artikel fest, stellen überaus wichtige Grenzgänger zwischen Lebens- und Informationswissenschaften dar.
description: Medienimpulse, Bd. 50 Nr. 2 (2012): 2/2012 - Biomacht, Biopolitik, Biomedien
Characterising Improvements in Photometric Redshift Probability Density Functions with Galaxy Morphology
Creators: name: Soo, John Y. H.
name: Joachimi, Benjamin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: In this work, we studied the impact of galaxy morphology on photometric redshift (photo-$z$) probability density functions (PDFs). By including galaxy morphological parameters like the radius, axis-ratio, surface brightness and the Sérsic index in addition to the $ugriz$ broadbands as input parameters, we used the machine learning photo-$z$ algorithm ANNz2 to train and test on galaxies from the Canada-France-Hawaii Telescope Stripe-82 (CS82) Survey. Metrics like the continuous ranked probability score (CRPS), probability integral transform (PIT), Bayesian odds parameter, and even the width and height of the PDFs were evaluated, and the results were compared when different number of input parameters were used during the training process. We find improvements in the CRPS and width of the PDFs when galaxy morphology has been added to the training, and the improvement is larger especially when the number of broadband magnitudes are lacking.
description: 4 pages, 1 figure, published in the Proceedings of the 14th Asia-Pacific Physics Conference (APPC) held in Kuching, Malaysia on 17-22 November 2019
Policey, Biopolitik und Liberalismus. Vom Zugriff der Macht auf das Leben (Bios)
Creators: name: Neurath, Wolfgang
Publisher: name: Medienimpulse
Year: 2014

description: Wolfgang Neurath beleuchtet die Debatten zur Biopolitik aus historischer Perspektive und zeigt auf, wie das Foucaultsche Konzept der gouvernementalité von der Policey des 18. Jahrhunderts bis hin zum aktuellen (Neo)liberalismus seine Macht keineswegs verloren hat. Dabei weist Neurath nach, dass die Gesundheitspolitik historisch gesehen zu einem eigenen Bereich der Politik wurde, der die Sorge um das Wohl der Bevölkerung als ökonomisches, sicherheitstechnisches und vor allem zivilisatorisches Interventionsfeld des Lebens begreift. In der Verlängerung des Lebens und im damit verbundenen Zugriff auf den bios nimmt die innere Konfiguration der Policey Machttechnologien vorweg, die dann im Zeitalter des (Neo)liberalismus ausgebaut und intensiviert werden.
description: Medienimpulse, Bd. 50 Nr. 2 (2012): 2/2012 - Biomacht, Biopolitik, Biomedien
Classical and generalized solutions of an alarm-taxis model
Creators: name: Fuest, Mario
name: Lankeit, Johannes
Publisher: name: arXiv
Year: 2024
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35K20, 92D40, 35Q92, 35A01, 35D99

description: In bounded, spatially two-dimensional domains, the system \begin{equation*}
 \left\lbrace\begin{alignedat}{3}
 u_t &= d_1 Δu && &&+ u(λ_1 - μ_1 u - a_1 v - a_2 w), \\
 v_t &= d_2 Δv &&- ξ\nabla \cdot (v \nabla u) &&+ v(λ_2 - μ_2 v + b_1 u - a_3 w),\\
 w_t &= d_3 Δw &&- χ\nabla \cdot (w \nabla (uv)) &&+ w(λ_3 - μ_3 w + b_2 u + b_3 v),
 \end{alignedat}\right. \end{equation*} complemented with initial and homogeneous Neumann boundary conditions, models the interaction between prey (with density $u$), predator (with density $v$) and superpredator (with density $w$), which preys on both other populations. Apart from random motion and prey-tactical behavior of the primary predator, the key aspect of this system is that the secondary predator reacts to alarm calls of the prey, issued by the latter whenever attacked by the primary predator.
 We first show in the pure alarm-taxis model, i.e. if $ξ= 0$, that global classical solutions exist.
 For the full model (with $ξ> 0$), the taxis terms and the presence of the term $-a_2 uw$ in the first equation apparently hinder certain bootstrap procedures, meaning that the available regularity information is rather limited. Nonetheless, we are able to obtain global generalized solutions. An important technical challenge is to guarantee strong convergence of (weighted) gradients of the first two solution components in order to conclude that approximate solutions converge to a generalized solution of the limit problem.
description: 18 pages
Schriftkultur und Wirtschaftsleben im spätantiken Ephesos. Neue Ostraka und Inschriften auf Gebrauchskeramik
Creators: name: Sänger, Patrick
Publisher: name: Zenodo
Year: 2021
Subjects: Ephesos (Spätantike)
Ostraka
Gebrauchskeramik
Open-Access-Online-Corpus

description: Im Zuge von Grabungen in den Ruinen des spätantiken Ephesos (5.–7. Jh. n. Chr.) wurden zwischen 2011 und 2015 ca. 60 neu gefundene Tonscherben mit Ritzinschriften entdeckt und freigelegt. Da sie von wesentlicher Bedeutung für das Verständnis der Schriftkultur und des Wirtschaftslebens im spätantiken Ephesos sind, wird neben einer monographischen Druckedition auch ein Open-Access-Online-Corpus erstellt, das u.a. die neu gefundenen Ostraka und Inschriften auf Gebrauchskeramik allgemein zugänglich macht.
Mind the app! Zur pädagogischen Vielseitigkeit von Web 2.0-Tools im Unterricht
Creators: name: Strasser, Thomas
Publisher: name: Medienimpulse
Year: 2014

description: Der vorliegende Beitrag behandelt das Phänomen Web 2.0 im bildungstechnischen Kontext. Der Terminus Web 2.0 wird in der Fachwelt als so genanntes „buzz word“ – ein oft genanntes Schlagwort – gehandelt, das sich vor allem im Bereich der Pädagogik bzw. Didaktik in einer Transitionsphase weg vom temporären Hype, hin zu einem wertvollen Ansatz für Bildungsinstitutionen befindet. Die große Anzahl an täglich erscheinenden Web 2.0-Applikationen bedarf konkreter Ansätze, um diese Informationsflut zu filtern und zu begutachten. Nur so können letztendlich bestimmte Web 2.0-Anwendungen für den Unterricht empfohlen werden. Durch eingehende Analyse bestehender Literatur zum Thema „Web 2.0 & Bildung“ und aufgrund der langjährigen praktischen Erfahrung des Autors als (E-Learning-)Lehrer, werden Charakteristika bildungstechnischer Web 2.0-Anwendungen in einem wissenschaftstheoretischen und in einem Best-Practice-Kontext herausgearbeitet. Der empirische Teil der Arbeit versucht, die im Theorie- und im Best-Practice-Teil erläuterten Spezifika von Bildungs-Apps mittels Online-Fragebögen für deutschsprachige PädagogInnen in einen messmethodischen Zusammenhang zu bringen
description: Medienimpulse, Bd. 50 Nr. 2 (2012): 2/2012 - Biomacht, Biopolitik, Biomedien
Epilepsy Seizure Detection and Prediction using an Approximate Spiking Convolutional Transformer
Creators: name: Chen, Qinyu
name: Sun, Congyi
name: Gao, Chang
name: Liu, Shih-Chii
Publisher: name: arXiv
Year: 2024
Subjects: subject: Signal Processing (eess.SP)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: Neural and Evolutionary Computing (cs.NE)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Epilepsy is a common disease of the nervous system. Timely prediction of seizures and intervention treatment can significantly reduce the accidental injury of patients and protect the life and health of patients. This paper presents a neuromorphic Spiking Convolutional Transformer, named Spiking Conformer, to detect and predict epileptic seizure segments from scalped long-term electroencephalogram (EEG) recordings. We report evaluation results from the Spiking Conformer model using the Boston Children's Hospital-MIT (CHB-MIT) EEG dataset. By leveraging spike-based addition operations, the Spiking Conformer significantly reduces the classification computational cost compared to the non-spiking model. Additionally, we introduce an approximate spiking neuron layer to further reduce spike-triggered neuron updates by nearly 38% without sacrificing accuracy. Using raw EEG data as input, the proposed Spiking Conformer achieved an average sensitivity rate of 94.9% and a specificity rate of 99.3% for the seizure detection task, and 96.8%, 89.5% for the seizure prediction task, and needs >10x fewer operations compared to the non-spiking equivalent model.
description: To be published at the 2024 IEEE International Symposium on Circuits and Systems (ISCAS), Singapore
Effect of alloying and microstructure on formability of advanced high-strength steels processed via quenching and partitioning
Creators: name: Xia, P.
name: Vercruysse, F.
name: Celada-Casero, C.
name: Verleysen, P.
name: Petrov, R. H.
name: Sabirov, I.
name: Molina-Aldareguia, J. M.
name: Smith, A.
name: Linke, B.
name: Thiessen, R.
name: Frometa, D.
name: Parareda, S.
name: Lara, A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The article focuses on the effect of alloying and microstructure on formability of advanced high strength steels (AHSSs) processed via quenching and partitioning (Q&P). Three different Q&P steels with different combination of alloying elements and volume fraction of retained austenite are subjected to uniaxial tensile and Nakajima testing. Tensile mechanical properties are determined, and the forming limit diagrams (FLDs) are plotted. Microstructure of the tested samples is analyzed, and dramatic reduction of retained austenite fraction is detected. It is demonstrated that all steels are able to accumulate much higher amount of plastic strain when tested using Nakajima method. The observed phenomenon is related to the multiaxial stress state and strain gradients through the sheet thickness resulting in a fast transformation of retained austenite, as well as the ability of the tempered martensitic matrix to accumulate plastic strain. Surprisingly, a Q&P steel with the highest volume fraction of retained austenite and highest tensile ductility shows the lowest formability among studied grades. The latter observation is related to the highest sum of fractions of initial fresh martensite and stress/strain induced martensite promoting formation of microcracks. Their role and ability of tempered martensitic matrix to accumulate plastic deformation during forming of Q&P steels is discussed.
description: 12 figures, 6 tables
Feshbach resonances and mesoscopic phase separation near a quantum critical point in multiband FeAs-based superconductors
Creators: name: Caivano, Rocchina
name: Fratini, Michela
name: Poccia, Nicola
name: Ricci, Alessandro
name: Puri, Alessandro
name: Ren, Zhi-An
name: Dong, Xiao-Li
name: Yang, Jie
name: Lu, Wei
name: Zhao, Zhong-Xian
name: Barba, Luisa
name: Bianconi, Antonio
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: High Tc superconductivity in FeAs-based multilayers (pnictides), evading temperature decoherence effects in a quantum condensate, is assigned to a Feshbach resonance (called also shape resonance) in the exchange-like interband pairing. The resonance is switched on by tuning the chemical potential at an electronic topological transition (ETT) near a band edge, where the Fermi surface topology of one of the subbands changes from 1D to 2D topology. We show that the tuning is realized by changing i) the misfit strain between the superconducting planes and the spacers ii) the charge density and iii) the disorder. The system is at the verge of a catastrophe i.e. near a structural and magnetic phase transition associated with the stripes (analogous to the 1/8 stripe phase in cuprates) order to disorder phase transition. Fine tuning of both the chemical potential and the disorder pushes the critical temperature Ts of this phase transition to zero giving a quantum critical point. Here the quantum lattice and magnetic fluctuations promote the Feshbach resonance of the exchange-like anisotropic pairing. This superconducting phase that resists to the attacks of temperature is shown to be controlled by the interplay of the hopping energy between stripes and the quantum fluctuations. The superconducting gaps in the multiple Fermi surface spots reported by the recent ARPES experiment of D. V. Evtushinsky et al. arXiv:0809.4455 are shown to support the Feshbach scenario.
description: 31 pages, 7 figures