cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
title: 'It's Not Just Radio': Models of Community Broadcasting in Britain and the United States
Creators: name: Coyer, Kate
Publisher: name: Goldsmiths, University of London
Year: 2009

description: Necessary and important focus has been given to the future of digital, satellite and Internet radio as a means of increasing flows of information and culture irrespective of geographic boundaries. At the same time, radio is primarily a local experience. This research examines the phenomenon of community radio through case studies in Britain and the United States. The contested site of audio broadcasting lies beyond the national framework via new technologies and, at the same time, is rooted locally. The political impetus for this project emerges out of the current media reform movements in both countries for the expansion of low power community radio and their connection to broader concerns around media democracy and pluralism. The research seeks to explore the phenomenon of community radio and how its characteristics are challenged in practice; the extent to which there exists both continuity and difference in the development of community radio sectors in both Britain and the United States; how radio is both de-linked from geography and rooted in localities; and whether or not the medium of radio itself embodies potential as a more participatory and democratic means of communication. This research is situated in both radio studies and alternative media studies. In order to investigate these questions, the research considers content production and internal organisational stmcture among its case studies, representing different models of community radio; examines the impact of technology on radio as a local space; and considers questions of media and democracy raised by community radio projects.
Amtliche Mitteilungen der Universität Dortmund Nr. 10/92
Creators: name: (:Unkn) Unknown
Publisher: name: Universität Dortmund
Year: 1992
Subjects: subject: 080

description: Amtlicher Teil: Studienordnung für den Studiengang Geschichte an der Universität Dortmund mit dem Abschluß "Erste Staatsprüfung für das Lehramt für die Sekundarstufe I"
description: Nichtamtlicher Teil: Verlust von Dienstausweisen
description: Amtliche Mitteilungen der Universität Dortmund ; 10, 1992
Determinants of the Performance of Social Entrepreneurial Firms in Ethiopia: The case of Selam children village and Eminence Social entrepreneurship
Creators: name: Abebe, Samuel
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2018

description: Social entrepreneurship is the practice of responding through transformative, financially sustainable innovations aimed at solving social problems at the nexus of the public, private, and nonprofit sectors. The performance of social entrepreneurs in Ethiopia is the prim are not deal with their priority of impact in an objective way with their priority of impact an objective way. Besides the subjective way and disaggregated way of explaining these factors, no research is done to the highlight the role of social entrepreneurs to the social and economic development. Hence the objective of this study examines the determinate factors in social entrepreneurs in the case of Selam children village and Eminence Social entrepreneurship. On this research the regression model is conducted to analyze one dependent and five independent variables to evaluate the performance of two social Entrepreneur firms. Multiple regressions resulted from 256 target populations with the sample of 75 respondents, who are employees of the targeted organizations depicted five significant determinant factors for social entrepreneur's performance: Those are planning, Information communication tools, government promotion strategy, Leadership style & Staff competency according to their contribution towards their impact on performance of social entrepreneur. These determinants factors collectively explain the performance of social entrepreneurs by 68.4% and the assessment showed that leadership style and staff competency were not significant as compared with other variables. Besides, planning, information communication tools and government promotion strategy were statically significant to study. This study highlighted which factors need special attention from different stakeholders with regard to their impact on the significant level of the determining factors in the performance of social entrepreneurs. Key words: - Social entrepreneurs, Performance, Determinate factors, Regression model, Information communication tools, Government promotion strategy, staff competency, leadership style.
First results from a microwave cavity axion search at 24 micro-eV
Creators: name: Brubaker, B. M.
name: Zhong, L.
name: Gurevich, Y. V.
name: Cahn, S. B.
name: Lamoreaux, S. K.
name: Simanovskaia, M.
name: Root, J. R.
name: Lewis, S. M.
name: Kenany, S. Al
name: Backes, K. M.
name: Urdinaran, I.
name: Rapidis, N. M.
name: Shokair, T. M.
name: van Bibber, K. A.
name: Palken, D. A.
name: Malnou, M.
name: Kindel, W. F.
name: Anil, M. A.
name: Lehnert, K. W.
name: Carosi, G.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We report on the first results from a new microwave cavity search for dark matter axions with masses above $20~μ\text{eV}$. We exclude axion models with two-photon coupling $g_{aγγ} \gtrsim 2\times10^{-14}~\text{GeV}^{-1}$ over the range $23.55~μ\text{eV} < m_a < 24.0~μ\text{eV}$. These results represent two important achievements. First, we have reached cosmologically relevant sensitivity an order of magnitude higher in mass than any existing limits. Second, by incorporating a dilution refrigerator and Josephson parametric amplifier, we have demonstrated total noise approaching the standard quantum limit for the first time in an axion search.
description: 5 pages, 3 figures, accepted for publication in PRL. v2: added changes made during the review process
Constraining Chameleon screening using galaxy cluster dynamics
Creators: name: Boumechta, Yacer
name: Haridasu, Balakrishna S.
name: Pizzuti, Lorenzo
name: Butt, Minahil Adil
name: Baccigalupi, Carlo
name: Lapi, Andrea
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We constrain the Chameleon \textit{screening} mechanism in galaxy clusters, essentially obtaining limits on the coupling strength $β$ and the asymptotic value of the field $ϕ_{\infty}$. For this purpose, we utilized a collection of the 9 relaxed galaxy clusters within the X-COP compilation in the redshift range of $z \le 0.1$. We implement the formalism assuming an NFW mass profile for the dark matter density and study the degeneracy present between the mass $\M$ and the chameleon coupling with a high degree of improvement in the constraints for excluded parameter space. We recast our constrain to an upper limit on the scalaron field in \fofr sub-class of models of $|f_{R0}|\le 9.2\times 10^{-6}$, using all the nine clusters and $|f_{R0}|\le 1.2\times 10^{-5}$ using only 5 clusters with WL priors taken into account, at a $95\%$ confidence level. These bounds are consistent with existing limits in the literature and tighter than the constraints obtained with the same method by previous studies.
description: Comments are welcome
The effect of the adiabatic assumption on asteroseismic scaling relations for luminous red giants
Creators: name: Zinn, Joel C.
name: Pinsonneault, Marc H.
name: Bildsten, Lars
name: Stello, Dennis
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Although stellar radii from asteroseismic scaling relations agree at the percent level with independent estimates for main sequence and most first-ascent red giant branch stars, the scaling relations over-predict radii at the tens of percent level for the most luminous stars ($R \gtrsim 30 R_{\odot}$). These evolved stars have significantly superadiabatic envelopes, and the extent of these regions increase with increasing radius. However, adiabaticity is assumed in the theoretical derivation of the scaling relations as well as in corrections to the large frequency separation. Here, we show that a part of the scaling relation radius inflation may arise from this assumption of adiabaticity. With a new reduction of Kepler asteroseismic data, we find that scaling relation radii and Gaia radii agree to within at least $2\%$ for stars with $R \lesssim 30 R_{\odot}$, when treated under the adiabatic assumption. The accuracy of scaling relation radii for stars with $50 R_{\odot} \lesssim R \lesssim 100 R_{\odot}$, however, is not better than $10\%-15\%$ using adiabatic large frequency separation corrections. We find that up to one third of this disagreement for stars with $R \approx 100 R_{\odot}$ could be caused by the adiabatic assumption, and that this adiabatic error increases with radius to reach $10\%$ at the tip of the red giant branch. We demonstrate that, unlike the solar case, the superadiabatic gradient remains large very deep in luminous stars. A large fraction of the acoustic cavity is also in the optically thin atmosphere. The observed discrepancies may therefore reflect the simplified treatment of convection and atmospheres.
description: Published in MNRAS
Amtliche Mitteilungen der Universität Dortmund Nr. 13/92
Creators: name: (:Unkn) Unknown
Publisher: name: Universität Dortmund
Year: 1992
Subjects: subject: 080

description: Amtlicher Teil: Benutzungsordnung für die Sportstätten (Innen- und Außenanlagen) der Universität Dortmund vom 16. September 1992
description: Amtliche Mitteilungen der Universität Dortmund ; 13, 1992
Planetary Defense Using Python: Measuring Deflection of the Didymos Binary Asteroid System by the NASA DART Mission
Creators: name: Nath, Arushi
Publisher: name: Zenodo
Year: 2023

description: The pace of discovery of near-earth asteroids outpaces current abilities to analyze them. Knowledge of an asteroid's physical properties is essential to deflect them. I developed open-source algorithms that combine images from robotic telescopes, open-data, and math to determine asteroids' size, rotation, and strength. I took observations of the Didymos binary asteroid, and my algorithm determined it to be 820m wide, with a 2.26-hour rotation period and rubble-pile strength. I measured a 35-minute decrease in the mutual orbital period after impact by the 2022 NASA DART Mission. External sources validated the findings. Every citizen scientist is now a planetary defender.
TU Tau B: The Peculiar 'Eclipse' of a possible proto-Barium Giant
Creators: name: Gray, Richard O.
name: Corbally, Christopher J.
name: Briley, Michael M.
name: McKay, Adam
name: Sims, Forrest
name: Boyd, David
name: Boussin, Christophe
name: McGahee, Courtney E.
name: Buchheim, Robert
name: Walker, Gary
name: Iadevaia, David
name: Fernandez, David Cejudo
name: Lemay, Damien
name: Martin, Jack
name: Grubb, Jim
name: Stiewing, Albert
name: Daglen, Joseph
name: Shank, Keith
name: Andrews, Sydney
name: Barnhardt, Nick
name: Clark, Rebekah
name: Corman, Hunter
name: Gomes, Sabina
name: Jonnalagadda, Agastya
name: McDaries, Theo
name: Mills, Ava
name: Newsom, Will
name: Slate, Andrew
name: Watts, Michael
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: TU Tau (= HD 38218 = HIP 27135) is a binary system consisting of a C-N carbon star primary and an A-type secondary. We report on new photometry and spectroscopy which tracked the recent disappearance of the A-star secondary. The dimming of the A-star was gradual and irregular, with one or more brief brightenings, implying the presence of nonhomogeneities in the carbon star outflow. We also present evidence that the A-star is actively accreting s-process enriched material from the carbon star and suggest that it will therefore eventually evolve into a Barium giant. This is an important system as well because the A-type star can serve as a probe of the outer atmosphere of the carbon star.
description: 9 pages, 9 figures, 4 tables, a number of amateur observatories made significant contributions to this research. Paper accepted for publication in The Astronomical Journal
Uncoupling System and Environment Simulation Cells for Fast-Scaling Modeling of Complex Continuum Embeddings
Creators: name: Medrano, Gabriel
name: Bainglass, Edan
name: Andreussi, Oliviero
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Continuum solvation models are becoming increasingly relevant in condensed matter simulations, allowing to characterize materials interfaces in the presence of wet electrified environments at a reduced computational cost with respect to all atomistic simulations. However, some challenges with the implementation of these models in plane-wave simulation packages still persists, especially when the goal is to simulate complex and heterogeneous environments. Among these challenges is the computational cost associated with large heterogeneous environments, which in plane-wave simulations has a direct effect on the basis-set size and, as a result, on the cost of the electronic structure calculation. Moreover, the use of periodic simulation cells are not well-suited for modeling systems embedded in semi-infinite media, which is often the case in continuum solvation models. To address these challenges, we present the implementation of a double-cell formalism, in which the simulation cell used for the continuum environment is uncoupled from the one used for the electronic-structure simulation of the quantum-mechanical system. This allows for a larger simulation cell to be used for the environment, without significantly increasing computational time. In this work, we show how the double-cell formalism can be used as an effective PBC correction scheme for non-periodic and partially periodic systems. The accuracy of the double-cell formalism is tested using representative examples with different dimensionalities, both in vacuum and in a continuum dielectric environment. Fast convergence and good speedups are observed for all the simulation setups, provided the quantum-mechanical simulation cell is chosen to completely fit the electronic density of the system.
Arctic curves of the $6$V model with partial DWBC and double Aztec rectangles
Creators: name: de Kemmeter, Jean-François
name: Debin, Bryan
name: Ruelle, Philippe
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: Combinatorics (math.CO)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Previous numerical studies have shown that in the disordered and anti-ferroelectric phases the six-vertex ($6$V) model with partial domain wall boundary conditions (DWBC) exhibits an arctic curve whose exact shape is unknown. The model is defined on a $s\times n$ square lattice ($s\leq n$). In this paper, we derive the analytic expression of the arctic curve, for $a=b=1$ and $c=\sqrt{2}$ ($Δ=0$), while keeping the ratio $s/n \,\in [0,1]$ as a free parameter. The computation relies on the tangent method. We also consider domino tilings of double Aztec rectangles and show via the tangent method that, for particular parameters, the arctic curve is identical to that of the $6$V model with partial DWBC. Our results are confirmed by extensive numerical simulations.
description: 42 pages, 18 figures
The Evaluation of Customer Satisfaction of Anbassa City Bus Service Enterprise
Creators: name: Tsegaye, Aschalew
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2015

description: Public enterprises are organizations established and owned by government to provide different services to the public. Most of the time these enterprises give their services to the public by collecting some amount of money which is less than the market price of the goods or services provided by them and sometimes with subsidy. Their customers are important stakeholders in organizations and their satisfaction is a priority to management. Most of these enterprises apply different types of reforms to improve their service provision capacity and customers' satisfaction. Currently Anbassa City Bus Service Enterprise (ACBSE) implemented BPR to improve its service quality and maximizing customers' satisfaction. This study was conducted to assess the service delivery performance and customers' satisfaction in the aftermath of implementing BPR. To achieve the objectives of this study, data was collected through questionnaire from a sample of 192 customers and employees of the Enterprise. These respondents were selected using simple random sampling method. Additional data was collected through interview from the General Manager and Public Transport Core Process Owner of the Enterprise. The data collected using the questionnaire were analyzed using statistical tools such as mean and frequency analysis. Service delivery of the Enterprise was evaluated by using service quality dimensions designed by Parasuraman et.al. (1988). The results of this evaluation indicate that, almost in all dimensions of service quality the Enterprise service provision rated as poor and customers are not satisfied except some factors within the dimensions. Generally, the finding of this study indicates that customers were not satisfied by overall service provision of the Enterprise and the service quality declined even if the Enterprise implemented BPR to improve its services. Based on the findings of the study, the researcher forwards some recommendations like maintaining effective complaint handling, supporting the service delivery by IT, empowering employees to serve their customers in proper way, and others which help to improve the Enterprise service delivery performance
Vibrationally resolved UV/Vis spectroscopy with time-dependent density functional based tight binding
Creators: name: Rüger, Robert
name: Niehaus, Thomas
name: van Lenthe, Erik
name: Heine, Thomas
name: Visscher, Lucas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: We report a time-dependent density functional based tight-binding (TD-DFTB) scheme for the calculation of UV/Vis spectra, explicitly taking into account the excitation of nuclear vibrations via the adiabatic Hessian Franck-Condon (AH|FC) method with a harmonic approximation for the nuclear wavefunction. The theory of vibrationally resolved UV/Vis spectroscopy is first summarized from the viewpoint of TD-DFTB. The method is benchmarked against time-dependent density functional theory (TD-DFT) calculations for strongly dipole allowed excitations in various aromatic and polar molecules. Using the recent 3ob:freq parameter set of Elstner's group, very good agreement with TD-DFT calculations using local functionals was achieved.
description: 14 pages, 19 figures
title: Nuclear magnetic resonance and dielectric spectroscopy of a simple supercooled liquid
title: 2-methyl tetrahydrofuran
titleType: AlternativeTitle
Creators: name: Böhmer, Roland
name: Qi, F.
name: El Goresy, T.
name: Döß, A.
name: Diezemann, G.
name: Hinze, G.
name: Sillescu, H.
name: Blochowicz, T.
name: Gainaru, C.
name: Rössler, E.
name: Zimmermann, H.
Publisher: name: American Institute of Physics
Year: 2003
Subjects: subject: 530

description: The small-molecule glass former methyl tetrahydrofuran (MTHF) was investigated using dielectric spectroscopy, spin-lattice relaxometry, multidimensional stimulated-echo nuclear magnetic resonance techniques, and field gradient diffusometry. We show experimentally that MTHF nicely fits into the pattern of related small-molecule glass-forming liquids, including the existence of a high-frequency contribution to the dielectric loss, the appearance of a pronounced translational enhancement, the dominance of small average rotational jump angles, and the existence of short-lived dynamical heterogeneity.
Can Gravitational Instantons Really Constrain Axion Inflation?
Creators: name: Hebecker, Arthur
name: Mangat, Patrick
name: Theisen, Stefan
name: Witkowski, Lukas T.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Axions play a central role in inflationary model building and other cosmological applications. This is mainly due to their flat potential, which is protected by a global shift symmetry. However, quantum gravity is known to break global symmetries, the crucial effect in the present context being gravitational instantons or Giddings-Strominger wormholes. We attempt to quantify, as model-independently as possible, how large a scalar potential is induced by this general quantum gravity effect. We pay particular attention to the crucial issue which solutions can or cannot be trusted in the presence of a moduli-stabilisation and a Kaluza-Klein scale. An important conclusion is that, due to specific numerical prefactors, the effect is surprisingly small even in UV-completions with the highest possible scale offered by string theory. As we go along, we discuss in detail Euclidean wormholes, cored and extremal instantons, and how the latter arise from 5d Reissner-Nordstrom black holes. We attempt to dispel possible doubts that wormholes contribute to the scalar potential by an explicit calculation. We analyse the role of stabilised dilaton-like moduli. Finally, we argue that Euclidean wormholes may be the objects satisfying the Weak Gravity Conjecture extended to instantons.
description: 66 pages, 10 figures. More details, especially concerning instanton summation, added
title: Government spending and unemployment in the OECD
title: Evidence from an annual panel VAR
titleType: AlternativeTitle
Creators: name: Juessen, Falko
name: Linnemann, Ludger
Publisher: name: Technische Universität Dortmund
Year: 2012
Subjects: subject: fiscal policy effects
subject: panel vector autoregressions
subject: sign restrictions
subject: simulation
subject: unemployment
subject: 310
subject: 330
subject: 620

description: We use a panel VAR to assess the dynamic effects of government spending on unemployment rates in OECD countries. We first present Monte Carlo evidence that the Hahn and Kuersteiner (2002) estimator produces almost unbiased estimates of impulse responses in an annual macro panel VAR. In the application, we find that positive shocks to government spending identified either through a Cholesky decomposition or by sign restrictions tend to lower the unemployment rate in the short run, though signifi cance depends on identification assumptions.
description: Discussion Paper / SFB 823 ; 08/2012
Measuring the speed of light with ultra-compact radio quasars
Creators: name: Cao, Shuo
name: Biesiada, Marek
name: Jackson, John
name: Zheng, Xiaogang
name: Zhao, Yuhang
name: Zhu, Zong-Hong
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In this paper, based on a 2.29 GHz VLBI all-sky survey of 613 milliarcsecond ultra-compact radio sources with $0.0035
description: 22 pages, 7 figures, accepted for publication in JCAP
Quantum mechanics is compatible with counterfactual definiteness
Creators: name: Kujala, Janne V.
name: Dzhafarov, Ehtibar N.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences
subject: 81P13, 81Q99, 60A99

description: Counterfactual definiteness (CFD) means that if some property is measured in some context, then the outcome of the measurement would have been the same had this property been measured in a different context. A context includes all other measurements made together with the one in question, and the spatiotemporal relations among them. The proviso for CFD is non-disturbance: any physical influence of the contexts on the property being measured is excluded by the laws of nature, so that no one measuring this property has a way of ascertaining its context. It is usually claimed that in quantum mechanics CFD does not hold, because if one assigns the same value to a property in all contexts it is measured in, one runs into a logical contradiction, or at least contravenes quantum theory and experimental evidence. We show that this claim is not substantiated if one takes into account that only one of the possible contexts can be a factual context, all other contexts being counterfactual. With this in mind, any system of random variables can be viewed as satisfying CFD. The concept of CFD is closely related to but distinct from that of noncontextuality, and it is the latter property that may or may not hold for a system, in particular being contravened by some quantum systems
Evidence for simultaneous jets and disk winds in luminous low-mass X-ray binaries
Creators: name: Homan, Jeroen
name: Neilsen, Joseph
name: Allen, Jessamyn L.
name: Chakrabarty, Deepto
name: Fender, Rob
name: Fridriksson, Joel K.
name: Remillard, Ronald A.
name: Schulz, Norbert
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Recent work on jets and disk winds in low-mass X-ray binaries (LMXBs) suggests that they are to a large extent mutually exclusive, with jets observed in spectrally hard states and disk winds observed in spectrally soft states. In this paper we use existing literature on jets and disk winds in the luminous neutron star (NS) LMXB GX 13+1, in combination with archival Rossi X-ray Timing Explorer data, to show that this source is likely able to produce jets and disk winds simultaneously. We find that jets and disk winds occur in the same location on the source's track in its X-ray color-color diagram. A further study of literature on other luminous LMXBs reveals that this behavior is more common, with indications for simultaneous jets and disk winds in the black hole LMXBs V404 Cyg and GRS 1915+105 and the NS LMXBs Sco X-1 and Cir X-1. For the three sources for which we have the necessary spectral information, we find that the simultaneous jets/winds all occur in their spectrally hardest states. Our findings indicate that in LMXBs with luminosities above a few tens of percent of the Eddington luminosity, jets and disk winds are not mutually exclusive, and that the presence of disk winds does not necessarily result in jet suppression.
description: Updated to match published version (2016, ApJ, 830, L5)
Thermodynamic inference in partially accessible Markov networks: A unifying perspective from transition-based waiting time distributions
Creators: name: van der Meer, Jann
name: Ertel, Benjamin
name: Seifert, Udo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The inference of thermodynamic quantities from the description of an only partially accessible physical system is a central challenge in stochastic thermodynamics. A common approach is coarse-graining, which maps the dynamics of such a system to a reduced effective one. While coarse-graining states of the system into compound ones is a well studied concept, recent evidence hints at a complementary description by considering observable transitions and waiting times. In this work, we consider waiting time distributions between two consecutive transitions of a partially observable Markov network. We formulate an entropy estimator using their ratios to quantify irreversibility. Depending on the complexity of the underlying network, we formulate criteria to infer whether the entropy estimator recovers the full physical entropy production or whether it just provides a lower bound that improves on established results. This conceptual approach, which is based on the irreversibility of underlying cycles, additionally enables us to derive estimators for the topology of the network, i.e., the presence of a hidden cycle, its number of states and its driving affinity. Adopting an equivalent semi-Markov description, our results can be condensed into a fluctuation theorem for the corresponding semi-Markov process. This mathematical perspective provides a unifying framework for the entropy estimators considered here and established earlier ones. The crucial role of the correct version of time-reversal helps to clarify a recent debate on the meaning of formal versus physical irreversibility. Extensive numerical calculations based on a direct evaluation of waiting-time distributions illustrate our exact results and provide an estimate on the quality of the bounds for affinities of hidden cycles.
Magneto-optical and EPR transitions in Raman heterodyne spectroscopy
Creators: name: Suter, Dieter
name: Schweika-Kresimon, Marc O.
name: Gutschank, Jörg
Publisher: name: The American Physical Society
Year: 2002
Subjects: subject: 530

description: Laser and microwave fields can be mixed in paramagnetic samples in a coherent Raman process. The radiation scattered in the forward direction contains frequency components at the sum and difference frequency. We consider the details of this scattering process in a static magnetic field, where two types of signals appear: magnetic-resonance transitions give rise to signals at fixed magnetic fields, independent of the laser frequency. Another set of resonances is determined by the optical transition frequencies. These resonances are particularly prominent in samples with narrow optical absorption lines. We derive a comprehensive theory that describes both contributions and compare it with experimental data from the R lines of ruby.
Emergent unitarity, all-loop cuts and integrations from the ABJM amplituhedron
Creators: name: He, Song
name: Kuo, Chia-Kai
name: Li, Zhenjie
name: Zhang, Yao-Qi
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We elaborate on aspects of a new positive geometry proposed recently, which was conjectured to be the four-point amplituhedron for ABJM theory. We study generalized unitarity cuts from the geometry, and in particular we prove that (1) the four-point integrand satisfies perturbative unitarity (or optical theorem) to all loops, which follows directly from the geometry, and (2) vanishing cuts involving odd-point amplitudes follow from the ``bipartite" nature of the associated ``negative geometries", which justifies their appearance in ABJM theory. We also take a first step in integrating the forms of these negative geometries and obtain an infrared-finite quantity up to two loops, from which we extract the cusp anomalous dimension at leading order.
description: 21 pages, many figures,minor changes
Fixed Line Telephone Service Failure and Recovery: A case study in Ethiopian Telecommunication Corporation
Creators: name: Biratu, Tamrat
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2010

description: This case study is about fixed line service failure and recovery performance of Ethiopian Telecommunications Corporation. The relevant data were collected through both secondary and primary sources. The data was analyzed using qualitatively and simple statistical tools like percentages, averages, frequency and totals. Cause and effect diagram was used in identifying the major causes of service failure and delay in service recovery. Aging of cables, poor quality of apparatus, theft, damages due to construction of roads and buildings, installation of water pipelines and electric lines by respective organization were found the major causes of fixed line service failure. The average failure rate for all zone offices during the last five years were 67.2% out of average 399413 connected lines. In relation to delay in service recovery, the major causes were work overload and lengthy process to complete legal process. Based on these, it is recommended that ETC should take proactive measures in relation to old network maintenance and should work closely with other organizations like Addis Ababa police, Ethiopian Electric Power Corporation, Ethiopian water and Sewerage authority, Road authority, and Ethiopian quality and standard authority.
M2-Branes And The (2,0) Superalgebra
Creators: name: Lambert, Neil
name: Sacco, Damiano
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We present a generalization of the six-dimensional (2,0) system of arXiv:1007.2982 to include a constant abelian 3-form. For vanishing 3-form this system is known to provide a variety descriptions of parallel M5-branes. For a particular choice of 3-form the system is shown to reduce to that of two M2-branes. Thus this generalised (2,0) system provides a unified description of two parallel M2-branes or M5-branes.
description: A reference was added and some minor changes
Emergence of chaotic hysteresis in a second-order non-autonomous chaotic circuit
Creators: name: Sivaganesh, G.
name: Srinivasan, K.
name: Fozin, T. Fonzin
name: Pradeep, R. Gladwin
Publisher: name: arXiv
Year: 2023
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: The observation of hysteresis in the dynamics of a third-order autonomous chaotic system namely, the {\it{Chua's}} circuit has been reported recently \cite{Gomes2023}. In the present work, we make a detailed study on the emergence of dynamical hysteresis in a simple second-order non-autonomous chaotic system namely, the {\it{Murali-Lakshmanan-Chua }} (MLC) circuit. The experimental realization of chaotic hysteresis is further validated by numerical simulation and analytical solutions. The presence of chaotic hysteresis in a second-order non-autonomous electronic circuit is reported for the first time. Multistable regions are observed in the dynamics of MLC with constant bias.
description: 27 Pages, 10 figures
Vacancy Relaxation in Cuprous Oxide (Cu$_{2-x}$O$_{1-y}$)
Creators: name: Frazer, Laszlo
name: Chang, Kelvin B.
name: Schaller, Richard D.
name: Poepplemeier, Kenneth R.
name: Ketterson, John B.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Phonons are produced when an excited vacancy in cuprous oxide (Cu$_2$O) relaxes. Time resolved luminescence was used to find the excited copper vacancy (acceptor) and oxygen vacancy (donor) trap levels and lifetimes. It was also used to determine the typical energy and number of phonons in the phonon pulses emitted by vacancies. The vacancy properties of cuprous oxide are controlled by several synthesis parameters and by the temperature. We directly demonstrate the absorption of light by oxygen vacancies with transient absorption. Copper and oxygen vacancies behave differently, in part because the two kinds of traps capture carriers from different states. For example, the copper vacancy luminescence lifetime is around 25 times greater at low temperature. However, both kinds of vacancy luminescence are consistent with a Poissonian multiple phonon emission model.
description: Corrected author metadata
Transmitting multiple high-frequency waves across length scales using the concurrent atomistic-continuum method
Creators: name: Davis, Alexander S.
name: Agrawal, Vinamra
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Coupled atomistic-continuum methods can describe large domains and model dynamic material behavior for a much lower computational cost than traditional atomistic techniques. However, these multiscale frameworks suffer from wave reflections at the atomistic-continuum interfaces due to the numerical discrepancy between the fine-scaled and coarse-scaled models. Such reflections are non-physical and may lead to unfavorable outcomes such as artificial heating in the atomistic region. In this work, we develop a technique to allow the full spectrum of phonons to be incorporated into the coarse-scaled regions of a periodic concurrent atomistic-continuum (CAC) framework. This scheme tracks phonons generated at various time steps and thus allows multiple high-frequency wave packets to travel between the atomistic and continuum regions. Simulations performed with this method demonstrate the ability of the technique to preserve the coherency of waves with a range of wavevectors as they propagate through the domain. This work has applications for systems with defined boundary conditions and may be extended to more complex problems involving waves randomly nucleated from an impact within a multiscale framework.
BeeTLe: A Framework for Linear B-Cell Epitope Prediction and Classification
Creators: name: Yuan, Xiao
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantitative Methods (q-bio.QM)
subject: Machine Learning (cs.LG)
subject: FOS: Biological sciences
subject: FOS: Computer and information sciences

description: The process of identifying and characterizing B-cell epitopes, which are the portions of antigens recognized by antibodies, is important for our understanding of the immune system, and for many applications including vaccine development, therapeutics, and diagnostics. Computational epitope prediction is challenging yet rewarding as it significantly reduces the time and cost of laboratory work. Most of the existing tools do not have satisfactory performance and only discriminate epitopes from non-epitopes. This paper presents a new deep learning-based multi-task framework for linear B-cell epitope prediction as well as antibody type-specific epitope classification. Specifically, a sequenced-based neural network model using recurrent layers and Transformer blocks is developed. We propose an amino acid encoding method based on eigen decomposition to help the model learn the representations of epitopes. We introduce modifications to standard cross-entropy loss functions by extending a logit adjustment technique to cope with the class imbalance. Experimental results on data curated from the largest public epitope database demonstrate the validity of the proposed methods and the superior performance compared to competing ones.
description: 18 pages, 3 figures, accepted at ECML PKDD 2023
Height-conserving quantum dimer models
Creators: name: Yan, Zheng
name: Meng, Zi Yang
name: Huse, David A.
name: Chan, Amos
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We propose a height-conserving quantum dimer model (hQDM) such that the lattice sum of its associated height field is conserved, and that it admits a Rokhsar-Kivelson (RK) point. The hQDM with minimal interaction range on the square lattice exhibits Hilbert space fragmentation and maps exactly to the XXZ spin model on the square lattice in certain Krylov subspaces. We obtain the ground-state phase diagram of hQDM via quantum Monte Carlo simulations, and demonstrate that a large portion of it is within the Krylov subspaces which admit the exact mapping to the XXZ model, with dimer ordered phases corresponding to easy-axis and easy-plane spin orders. At the RK point, the apparent dynamical exponents obtained from the single mode approximation and the height correlation function show drastically different behavior across the Krylov subspaces, exemplifying Hilbert space fragmentation and emergent glassy phenomena.
description: 5+14 pages, 4+10 figures
Topological Gapless Phases in Non-Symmorphic Antiferromagnets
Creators: name: Brzezicki, Wojciech
name: Cuoco, Mario
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Topologically protected fermionic quasiparticles occur in metals with band degeneracy as a consequence of band structure topology. Here we unveil topological semimetal and metal phases in a variety of non-symmorphic collinear antiferromagnets with glide reflection symmetry, a combination of mirror and half-lattice translation. We find gapless phases with Dirac points having multiple symmetry-protection as well as electronic structures with triple and quadruple band-crossing points. Glide semimetal is shown to be converted into a topological phase with non-trivial $\mathbb{Z}_2$ topological charges at the Dirac points due to inversion and time-inversion symmetry combination. More striking is the emergence of a hidden non-unitary relation between the states in the glide sectors that provide a general mechanism to get multiple band touching points. The split Fermi points uncover a $\mathbb{Z}_2$ protection that drives the changeover of the multiple-degenerate gapless phase into a topological metal built from their connection through distinct Fermi lines. Besides a new perspective of ordered states in complex materials, our findings indicate that novel topological gapless phases and edge states may occur in a wide class of magnetic systems.
description: 21 pages, 5 figures
Long Distance GNSS-Denied Visual Inertial Navigation for Autonomous Fixed Wing Unmanned Air Vehicles: SO(3) Manifold Filter based on Virtual Vision Sensor
Creators: name: Gallo, Eduardo
name: Barrientos, Antonio
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: This article proposes a visual inertial navigation algorithm intended to diminish the horizontal position drift experienced by autonomous fixed wing UAVs (Unmanned Air Vehicles) in the absence of GNSS (Global Navigation Satellite System) signals. In addition to accelerometers, gyroscopes, and magnetometers, the proposed navigation filter relies on the accurate incremental displacement outputs generated by a VO (Visual Odometry) system, denoted here as a Virtual Vision Sensor or VVS, which relies on images of the Earth surface taken by an onboard camera and is itself assisted by the filter inertial estimations. Although not a full replacement for a GNSS receiver since its position observations are relative instead of absolute, the proposed system enables major reductions in the GNSS-Denied attitude and position estimation errors. In order to minimize the accumulation of errors in the absence of absolute observations, the filter is implemented in the manifold of rigid body rotations or SO (3). Stochastic high fidelity simulations of two representative scenarios involving the loss of GNSS signals are employed to evaluate the results. The authors release the C++ implementation of both the visual inertial navigation filter and the high fidelity simulation as open-source software.
description: 27 pages, 14 figures. arXiv admin note: substantial text overlap with arXiv:2205.13242
Street Vending and Local Authorities in Addis Ababa City: Challenges and the Way Forward
Creators: name: Alebachew, Amsale
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2017

description: The study was aimed to analyze the factor that challenges the street vendors as well the Addis Ababa city authorities face to manage street vendors and keep the city in order. 140 street vendors were chosen from five selected sub cities. Since no registered street vendors, the sample size of the selected street vendors from the sub cities were taken based on proportionate of legal registered traders In This study, four major challenging factors faced by street venders during the operation of their task were identified to be financial constraints, problems of work environment, problems of social security and environmental problem. Interestingly, according to this study, street vendors create an enabling environment to improve one's livelihoods and to support the family. In addition, they were found to offer low priced commodities for the poorer segment of the society. Nevertheless, street vending was also found to create traffic congestions and hinder free movement of the pedestrians. Besides they were attributed to weaken city's economy because vendors do not pay trading tax. But, there are still conflict between authorities and vendors over licensing, taxation and encroachment of public places and pavements. In spite of its crucial role for providing employment and livelihoods to both urban and rural poor, its economic importance was rarely recognized either in national poverty reduction strategies or in city governance initiatives. Therefore, appropriately addressing the practical reality of the work process and the role of vendors in the urban economy, and effectively protect vendors' basic rights to livelihood and property. providing free-space, regulating the street vendors by issuing license, providing training and credit, developing small-scale agro-industries in rural areas, including permanent markets and working places in the master plan of a city were recommended. Key Words: Street vendors, City Authorities, Challenging factors
Dynamic Frame Interpolation in Wavelet Domain
Creators: name: Kong, Lingtong
name: Jiang, Boyuan
name: Luo, Donghao
name: Chu, Wenqing
name: Tai, Ying
name: Wang, Chengjie
name: Yang, Jie
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Video frame interpolation is an important low-level vision task, which can increase frame rate for more fluent visual experience. Existing methods have achieved great success by employing advanced motion models and synthesis networks. However, the spatial redundancy when synthesizing the target frame has not been fully explored, that can result in lots of inefficient computation. On the other hand, the computation compression degree in frame interpolation is highly dependent on both texture distribution and scene motion, which demands to understand the spatial-temporal information of each input frame pair for a better compression degree selection. In this work, we propose a novel two-stage frame interpolation framework termed WaveletVFI to address above problems. It first estimates intermediate optical flow with a lightweight motion perception network, and then a wavelet synthesis network uses flow aligned context features to predict multi-scale wavelet coefficients with sparse convolution for efficient target frame reconstruction, where the sparse valid masks that control computation in each scale are determined by a crucial threshold ratio. Instead of setting a fixed value like previous methods, we find that embedding a classifier in the motion perception network to learn a dynamic threshold for each sample can achieve more computation reduction with almost no loss of accuracy. On the common high resolution and animation frame interpolation benchmarks, proposed WaveletVFI can reduce computation up to 40% while maintaining similar accuracy, making it perform more efficiently against other state-of-the-arts. Code is available at https://github.com/ltkong218/WaveletVFI.
description: Accepted by IEEE TIP