cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Active Restoration of Lost Audio Signals Using Machine Learning and Latent Information
Creators: name: Cheddad, Zohra Adila
name: Cheddad, Abbas
Publisher: name: arXiv
Year: 2021
Subjects: subject: Audio and Speech Processing (eess.AS)
subject: Machine Learning (cs.LG)
subject: Sound (cs.SD)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Digital audio signal reconstruction of a lost or corrupt segment using deep learning algorithms has been explored intensively in recent years. Nevertheless, prior traditional methods with linear interpolation, phase coding and tone insertion techniques are still in vogue. However, we found no research work on reconstructing audio signals with the fusion of dithering, steganography, and machine learning regressors. Therefore, this paper proposes the combination of steganography, halftoning (dithering), and state-of-the-art shallow and deep learning methods. The results (including comparing the SPAIN, Autoregressive, deep learning-based, graph-based, and other methods) are evaluated with three different metrics. The observations from the results show that the proposed solution is effective and can enhance the reconstruction of audio signals performed by the side information (e.g., Latent representation) steganography provides. Moreover, this paper proposes a novel framework for reconstruction from heavily compressed embedded audio data using halftoning (i.e., dithering) and machine learning, which we termed the HCR (halftone-based compression and reconstruction). This work may trigger interest in optimising this approach and/or transferring it to different domains (i.e., image reconstruction). Compared to existing methods, we show improvement in the inpainting performance in terms of signal-to-noise ratio (SNR), the objective difference grade (ODG) and Hansen's audio quality metric. In particular, our proposed framework outperformed the learning-based methods (D2WGAN and SG) and the traditional statistical algorithms (e.g., SPAIN, TDC, WCP).
description: 18 Pages, 2 Tables, 8 Figures
A Large-D Weyl Invariant String Model in Anti-de Sitter Space
Creators: name: Davies, Ian
name: Mansfield, Paul
Publisher: name: arXiv
Year: 2002
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Strings propagating in AdS_{D+1} are made Weyl invariant to leading order in large D by a ghost-matter coupling that preserves the Poincare symmetry of the boundary.
description: LaTeX, 5pp, no figures
E$_{7(7)}$ Exceptional Field Theory in Superspace
Creators: name: Butter, Daniel
name: Samtleben, Henning
name: Sezgin, Ergin
Publisher: name: arXiv
Year: 2018
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We formulate the locally supersymmetric E$_{7(7)}$ exceptional field theory in a $(4+56|32)$ dimensional superspace, corresponding to a 4D $N\!=\!8$ "external" superspace augmented with an "internal" 56-dimensional space. This entails the unification of external diffeomorphisms and local supersymmetry transformations into superdiffeomorphisms. The solutions to the superspace Bianchi identities lead to on-shell duality equations for the $p$-form field strengths for $p\leq 4$. The reduction to component fields provides a complete description of the on-shell supersymmetric theory. As an application of our results, we perform a generalized Scherk-Schwarz reduction and obtain the superspace formulation of maximal gauged supergravity in four dimensions parametrized by an embedding tensor.
description: 42 pages
Computing the rational torsion of an elliptic curve using Tate normal form
Creators: name: García, I.
name: Acosta, M. A. Olalla
name: Tornero, J. M.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 11G05

description: It is a classical result (apparently due to Tate) that all elliptic curves with a torsion point of order n ($4 \leq n \leq 10$, or n = 12) lie in a one-parameter family. However, this fact does not appear to have been used ever for computing the torsion of an elliptic curve. We present here a extremely down-to-earth algorithm using the existence of such a family.
description: 14 pages
The ground beneath us : managing soil at UBC for improved drainage and reduced compaction
Creators: name: Philpott, Tim
Publisher: name: The University of British Columbia
Year: 2012

description: Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report.”
Causality Constraints on Gravitational Effective Field Theories
Creators: name: de Rham, Claudia
name: Tolley, Andrew J.
name: Zhang, Jun
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider the effective field theory of gravity around black holes, and show that the coefficients of the dimension-8 operators are tightly constrained by causality considerations. Those constraints are consistent with -- but tighter than -- previously derived causality and positivity bounds and imply that the effects of one of the dimension-8 operators by itself cannot be observable while remaining consistent with causality. We then establish in which regime one can expect the generic dimension-8 and lower order operators to be potentially observable while preserving causality, providing a theoretical prior for future observations. We highlight the importance of "infrared causality" and show that the requirement of "asymptotic causality" or net (sub)luminality would fail to properly diagnose violations of causality.
description: 12 pages, 4 figures, typos corrected, constraints on the dim-6 operators updated
Binary phase separation in a collection of self-propelled particle with variable speed
Creators: name: Singh, Jay Prakash
name: Mishra, Shradha
Publisher: name: arXiv
Year: 2019
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We study the collective behavior of binary mixture of self-propelled particles. Particles moves along their heading direction with {\it variable speed} and interact through short range alignment interaction. A variable speed parameter $γ>0$ is introduced such that for $γ=0.0$ model reduces to {\it constant speed} Vicsek's model. We mix the particles with two different $γ$'s and study the steady state behavior of the mixture for different choice of $γ$'s and noise strength. One of the $γ$ is kept fixed to $1.0$ and another one is varied from small $0.0$ to larger values $8.0$. Properties of system is characterise by two types of order parameters (i) orientation order parameter, which is a measure of ordering in the system and (ii) density order parameter, which measures the phase separation is the system. For all set of $γ$'s, system shows a transition from disorder-to-ordered state on the variation of noise strength. The nature of transition and critical noise is independent of value of $γ$, which is also supported from coarse-grained hydrodynamic study. On the variation of system parameters, ($γ$'s, $η$), we find four distinct phases, (i) ordered phase separated, (ii) ordered mixed, (iii) disordered mixed and (iv) disordered phase segragated. Our study shade light on different phases of mixture of different types of active particles.
description: 18 pages,7 figurs
Soft modes in Fermi liquids at arbitrary temperatures
Creators: name: Belitz, D.
name: Kirkpatrick, T. R.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We use kinetic-theory methods to analyze Landau Fermi-liquid theory, and in particular to investigate the number and nature of soft modes in Fermi liquids, both in the hydrodynamic and the collisionless regimes. In the hydrodynamic regime we show that Fermi-liquid theory is consistent with Navier-Stokes hydrodynamics at all temperatures. The soft modes are the ones familiar from classical hydrodynamics that are controlled by the five conservation laws; namely, two first-sound modes, two shear diffusion modes, and one heat diffusion mode. These modes have a particle-like spectrum and are soft, or scale invariant, at all temperatures. In the collisionless regime we show that the entire single-particle distribution function is soft with a continuous part of the spectrum. This continuous soft mode, which is well known but often not emphasized, has important physical consequences, e.g., for certain quantum phase transitions. In addition, there are the well known soft zero-sound excitations that describe angular fluctuations of the Fermi surface; their spectra are particle-like. They are unrelated to conservation laws, acquire a mass at any nonzero temperature, and their number depends on the strength of the quasiparticle interaction. We also discuss the fates of these two families of soft modes as the temperature changes. With increasing temperature the size of the collisionless regime shrinks, the damping of the modes grows, and eventually all of the collisionless modes become overdamped. In their stead the five hydrodynamic modes appear in the hydrodynamic regime at asymptotically low frequencies. The two families of soft modes are unrelated and have very different physical origins.In charged Fermi liquids the first-sound modes in the hydrodynamic regime and the l=0 zero-sound modes in the collisionless regime get replaced by plasmons, all other modes remain soft.
description: 24pp, 3 figs
title: Braunschweigische Anzeigen : offizielles Regierungs- und Anzeigeblatt. 51. Jahr 1795
Creators: name: :None
Publisher: name: Waisenhaus-Buchdruckerei
Year: 1795
Subjects: subject: Brunsvicensien der Universitätsbibliothek Braunschweig
subject: Braunschweigische Anzeigen
subject: 902

description: Braunschweigische Anzeigen: offizielles Regierungs- und Anzeigeblatt, vol. 51. 1795
$η$ photoproduction off the deuteron and low-energy $η$-nucleon interaction
Creators: name: Nakamura, S. X.
name: Kamano, H.
name: Ishikawa, T.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We study $η$ photoproduction off the deuteron ($γd\toηpn$) at a special kinematics: $\sim 0.94$ GeV of the photon beam energy and $\sim 0^\circ$ of the scattering angle of the proton. This kinematics is ideal to extract the low-energy $η$-nucleon scattering parameters such as $a_{ηN}$ (scattering length) and $r_{ηN}$ (effective range) because the $η$-nucleon elastic scattering is significantly enhanced. We show that if a ratio $R$, the $γd\toηpn$ cross section divided by the $γp\toηp$ cross section convoluted with the proton momentum distribution in the deuteron, is measured with 5% error, ${\rm Re}[a_{ηN}]$ (${\rm Re}[r_{ηN}]$) can be determined at the precision of $\sim\pm$0.1 fm ($\sim\pm$0.5 fm), significantly narrowing down the currently estimated range of the parameters. The measurement is ongoing at the Research Center for Electron Photon Science (ELPH), Tohoku University.
description: 4 pages, 5 figures, Contribution to the Proceedings for 8th International Conference on Quarks and Nuclear Physics (QNP2018), November 13-17, 2018, Tsukuba, Japan
Self-organized Networks of Competing Boolean Agents
Creators: name: Paczuski, Maya
name: Bassler, Kevin E.
name: Corral, Alvaro
Publisher: name: arXiv
Year: 1999
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: A model of Boolean agents competing in a market is presented where each agent bases his action on information obtained from a small group of other agents. The agents play a competitive game that rewards those in the minority. After a long time interval, the poorest player's strategy is changed randomly, and the process is repeated. Eventually the network evolves to a stationary but intermittent state where random mutation of the worst strategy can change the behavior of the entire network, often causing a switch in the dynamics between attractors of vastly different lengths.
description: 4 pages, 3 included figures. Some text revision and one new figure added. To appear in PRL
Excitation of a Kaluza-Klein mode by parametric resonance
Creators: name: Mukohyama, Shinji
Publisher: name: arXiv
Year: 1997
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In this paper we investigate a parametric resonance phenomenon of a Kaluza-Klein mode in a $D$-dimensional generalized Kaluza-Klein theory. As the origin of the parametric resonance we consider a small oscillation of a scale of the compactification around a today's value of it. To make our arguments definite and for simplicity we consider two classes of models of the compactification: those by $S_{d}$ ($d=D-4$) and those by $S_{d_{1}}\times S_{d_{2}}$ ($d_1\ge d_2$, $d_{1}+d_{2}=D-4$). For these models we show that parametric resonance can occur for the Kaluza-Klein mode. After that, we give formulas of a creation rate and a number of created quanta of the Kaluza-Klein mode due to the parametric resonance, taking into account the first and the second resonance band. By using the formulas we calculate those quantities for each model of the compactification. Finally we give conditions for the parametric resonance to be efficient and discuss cosmological implications.
description: 36 pages, Latex file, Accepted for publication in Physical Review D
title: Braunschweigische Anzeigen : offizielles Regierungs- und Anzeigeblatt. 58. Jahr 1802
Creators: name: :None
Publisher: name: Waisenhaus-Buchdruckerei
Year: 1802
Subjects: subject: Brunsvicensien der Universitätsbibliothek Braunschweig
subject: Braunschweigische Anzeigen
subject: 902

description: Braunschweigische Anzeigen: offizielles Regierungs- und Anzeigeblatt, vol. 58. 1802
Determining temperature and Rabi frequency regarding trapped ions in Doppler cooling: An analytic investigation
Creators: name: Yan, Lei-Lei
name: Su, Shi-Lei
name: Feng, Mang
Publisher: name: arXiv
Year: 2019
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Doppler cooling with lasers is essential to ions' trapping and also a preliminary step towards achievement of ultracold ions. Due to lack of effective tools, experimentally monitoring the ions' temperature and the laser-ion coupling is difficult in Doppler cooling. Here we analytically explore the Doppler cooling process of trapped ions, exemplified by $^{40}$Ca$^{+}$, by solving the friction coefficient in the Doppler cooling with respect to a thermal bath, particularly, to a bath with large heating rate. We show four regions for cooling and heating induced by the three-level electromagnetically induced transparency and propose a practical method for measuring the Rabi frequency by the Doppler cooling window. In addition, the final temperature of the laser-cooled ions can be obtained analytically in the case of a weak thermal bath, whereas for the strong thermal bath this requires numerical treatment due to involvement of the Doppler shift and large Lamb-Dicke parameter. Our analytic results would help for understanding many experimental observations, such as configuration phase transition, phonon laser and thermodynamics regarding hot trapped ions.
description: 10 Figures
Spontaneous Symmetry Breaking in Noncommutative Field Theory
Creators: name: Girotti, H. O.
name: Gomes, M.
name: Petrov, A. Yu.
name: Rivelles, V. O.
name: da Silva, A. J.
Publisher: name: arXiv
Year: 2002
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The spontaneous symmetry breaking of rotational O(N) symmetry in noncommutative field theory is investigated in a 2+1 dimensional model of scalar fields coupled through a combination of quartic and sextuple self-interactions. There are five possible orderings of the fields in the sextuple interaction and two for the quartic interaction. At one loop, we prove that for some choices of these orderings there is the absence of IR/UV mixing and the appearance of massless excitations. A supersymmetric extension of the model is also studied. Supersymmetry puts additional constraints on the couplings but for any given N there is a Moyal ordering of the superfields for which the requirement for the existence of Goldstone bosons is satisfied. For some ordering and when N goes to infinity we find evidence that the model is renormalizable to all orders in perturbation theory. We also consider a generic chiral model in 3+1 dimensions whose superpotential is invariant under local gauge transformations. We find that for any value of N there is no one loop correction to the pion mass and that, at two loops, there are no pion mass corrections for slowly varying superfields so that Goldstone theorem holds true. We also find a new purely noncommutative coupling which gives contributions starting at order N-2 loops.
description: 17 pages, 6 figues, revtex, (V2) acknowledgment added, (v3) minor changes
Lensing by gravitational waves in scalar-tensor gravity: Einstein frame analysis
Creators: name: Faraoni, Valerio
name: Gunzig, Edgard
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The amplification of a light beam due to intervening gravitational waves is studied. The previous Jordan frame result according to which the amplification is many orders of magnitude larger in scalar-tensor gravity than in general relativity does not hold in the Einstein conformal frame. Lensing by gravitational waves is discussed in relation to the ongoing and proposed VLBI observations aimed at detecting the scintillation effect.
description: 12 pages, LaTeX, to appear in Astronomy & Astrophysics
Evaluating peak demand management alternatives for the University of British Columbia
Creators: name: Rampley, Greg
Publisher: name: The University of British Columbia
Year: 2012

description: Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report."
A henselian preparation theorem
Creators: name: Moret-Bailly, Laurent
Publisher: name: arXiv
Year: 2021
Subjects: subject: Commutative Algebra (math.AC)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 13J15, 13B40, 13P15

description: We prove an analogue of the Weierstrass preparation theorem for henselian pairs, generalizing the local case recently proved by Bouthier and {\v C}esnavi{\v c}ius. As an application, we construct a henselian analogue of the resultant of p-adic series defined by Berger.
description: 10 pages. Final version, dedicated to Moshe Jarden
Interaction of surface acoustic waves with electronic excitations in graphene
Creators: name: Hernández-Mínguez, A.
name: Liou, Y. -T.
name: Santos, P. V.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Applied Physics (physics.app-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: This article reviews the main theoretical and experimental advances regarding the interaction between surface acoustic waves (SAWs) and electronic excitations in graphene. The coupling of the graphene electron gas to the SAW piezoelectric field can modify the propagation properties of the SAW, and even amplify the intensity of SAWs traveling along the graphene layer. Conversely, the periodic electric and strain fields of the SAW can be used to modify the graphene Dirac cone and to couple light into graphene plasmons. Finally, SAWs can generate acousto-electric currents in graphene. These increase linearly with the SAW frequency and power but, in contrast to conventional currents, they depend non-monotonously on the graphene electric conductivity. Most of these functionalities have been reported in graphene transferred to the surface of strong piezoelectric insulators. The recent observation of acousto-electric currents in epitaxial graphene on SiC opens the way to the large-scale fabrication of graphene-based acousto-electric devices patterned directly on a semi-insulating wafer.
Fate of False Vacuum in Non-perturbative Regimes
Creators: name: Frasca, Marco
name: Ghoshal, Anish
name: Okada, Nobuchika
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We use some exact results in the scalar field theory to revise the analysis by Coleman and Callan about the false vacuum decay and propose a simple non-perturbative formalism. We introduce exact Green's function which incorporates non-perturbative corrections in the strong coupling regimes of the theory. The solution of the scalar field theory involves Jacobi elliptical function and has been used to calculate the effective potential for any arbitrary coupling values. We demonstrate the use of this formalism in a simple $λϕ^4$ theory and show that the effective potential exhibits a false minimum at the origin. We then calculate the false vacuum decay rate and suggest simple analytic formulas which may be useful for the analysis for the first order phase transition beyond the perturbative regime. In our methodology, we show that the standard results obtained in perturbation theory are reproduced by taking the coupling values very small.
description: 12 pages, 3 figures. Version accepted for publication in Journal of Physics G
Computer simulation of shear flow in simple fluids
Creators: name: Hood, Lindsay Malcolm
Publisher: name: The Australian National University
Year: 1989
Subjects: subject: Fluids
subject: Shear flow Mathematical models
subject: Molecular dynamics

description: Computer simulation of shear flow in fluids has become an important technique in our understanding of the non-linear behaviour of fluids subjected to an external field. An important method for studying fluids from the atomic or molecular level is Molecular Dynamics. Conventional molecular dynamics simulations of shear flow have been performed at constant shear rate and constant pressure. In this thesis we describe how to perform simulations at constant shear stress or constant pressure, which are the usual experimental conditions. The theory used in deriving the constant stress equations is quite general and can be applied for fields other than shear flow, allowing one to simulate at constant thermodynamic force or flux. The constant pressure simulations show clearly the difference between shear thinning and shear dilatancy, a point that has caused confusion in the rheological literature. Efficient computational methods are important as some simulations can take hundreds of hours of computer time. The arrival of a vector processor at the A.N.U. has necessitated the experimentation with algorithms, with substantial performance gains over a standard code. These increases in performance have allowed us to complete a thorough study of shear flow at constant pressure for the soft sphere system, which complements a large body of data at constant density from other workers. Also a thorough study of shear flow in two dimensions has been completed. The two dimensional system shows a large dependence on system size, and we have been able to show the transition from small system behaviour to large system behaviour.
Enhanced pyroelectric and piezoelectric properties of PZT with aligned porosity for energy harvesting applications
Creators: name: Zhang, Yan
name: Xie, Mengying
name: Roscow, James
name: Bao, Yinxiang
name: Zhou, Kechao
name: Zhang, Dou
name: Bowen, Chris R.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: This paper demonstrates the significant benefits of exploiting highly aligned porosity in piezoelectric and pyroelectric materials for improved energy harvesting performance. Porous lead zirconate (PZT) ceramics with aligned pore channels and varying fractions of porosity were manufactured in a water-based suspension using freeze casting. The aligned porous PZT ceramics were characterized in detail for both piezoelectric and pyroelectric properties and their energy harvesting performance figures of merit were assessed parallel and perpendicular to the freezing direction. As a result of the introduction of porosity into the ceramic microstrucutre, high piezoelectric and pyroelectric harvesting figures of merits were achieved for porous freeze-cast PZT compared to dense PZT due to the reduced permittivity and volume specific heat capacity. Experimental results were compared to parallel and series analytical models with good agreement and the PZT with porosity aligned parallel to the freezing direction exhibited the highest piezoelectric and pyroelectric harvesting response; this was a result of the enhanced interconnectivity of the ferroelectric material along the poling direction and reduced fraction of unpoled material that leads to a higher polarization. A complete thermal energy harvesting system, composed of an parallel-aligned PZT harvester element and an AC/DC converter successfully demonstrated by charging a storage capacitor. The maximum energy density generated by the 60 vol.% porous parallel-connected PZT when subjected to thermal oscillations was 1653 μJ/cm3 respectively, which was 374% higher than that of the dense PZT with an energy density of 446 μJ/cm3. The results are of benefit for the design and manufacture of high performance porous pyroelectric and piezoelectric materials in devices for energy harvesting and sensor applications.
Circular Kinks on the Surface of Granular Material Rotated in a Tilted Spinning Bucket
Creators: name: Yoon, Sangsoo
name: Eom, Byeong-ho
name: Lee, Jysoo
name: Yu, Insuk
Publisher: name: arXiv
Year: 1999
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We find that circular kinks form on the surface of granular material when the axis of rotation is tilted more than the angle of internal friction of the material. Radius of the kinks is measured as a function of the spinning speed and the tilting angle. Stability consideration of the surface results in an explanation that the kink is a boundary between the inner unstable and outer stable regions. A simple cellular automata model also displays kinks at the stability boundary.
Penrose limit of a non-supersymmetric RG fixed point
Creators: name: Casero, Roberto
Publisher: name: arXiv
Year: 2002
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We extend the BMN duality between IIB superstring theory on a pp-wave background and a sector of N=4 super Yang-Mills theory to the non-supersymmetric and unstable background built by Romans as a compactification on a U(1) bundle over CP2 with 3-form and 5-form field strength fluxes. We obtain a stable theory with the fewest number of supercharges (e.g. 16) allowed by this kind of solutions and make conjectures on the dual gauge theory.
description: 30 pages, latex; v2 typos corrected; v3 typos corrected, Nuclear Physics B version
Additional file 1: of Association of pathway mutation with survival after recurrence in colorectal cancer patients treated with adjuvant fluoropyrimidine and oxaliplatin chemotherapy
Creators: name: Lee, Dae-Won
name: Sae-Won Han
name: Yongjun Cha
name: Bae, Jeong
name: Hwang-Phill Kim
name: Jaemyun Lyu
name: Hyojun Han
name: Hyoki Kim
name: Jang, Hoon
name: Duhee Bang
name: Won, Jae-Kyung
name: Seung-Yong Jeong
name: Park, Kyu
name: Gyeong Kang
name: Tae-You Kim
Publisher: name: figshare
Year: 2019
Subjects: subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Genetics
subject: Evolutionary Biology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Immunology
subject: FOS: Clinical medicine
subject: 69999 Biological Sciences not elsewhere classified
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Cancer
subject: 110309 Infectious Diseases
subject: FOS: Health sciences

description: Table S1. Mutation rate of 40 genes included in the study. Table S2. Mutation rate of critical pathways according to histology. Table S3. Survival after recurrence according to each gene mutation. (Genes with mutation rate over 5%). Table S4. Detailed profile of TGF-Î˛ pathway mutation. (DOCX 60 kb)
Logistic elliptic equation with a nonlinear boundary condition arising from coastal fishery harvesting
Creators: name: Umezu, Kenichiro
Publisher: name: arXiv
Year: 2022
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: Let $01$ is subcritical, we prove that in the case of $λ_Ω>1$, there exist at least two positive solutions for $λ>0$ sufficiently small but no positive solutions for $λ>0$ large enough. In the case of $λ_Ω<1$, there exists at least one positive solution for every $λ>0$. Here, $λ_Ω>0$ is the smallest eigenvalue of $-Δ$ under the Dirichlet boundary condition. An interpretation of our main results from an ecological viewpoint is presented.
description: to appear in Nonlinear Analysis: Real World Applications
Bounds on rare decays of $η$ and $η^\prime$ mesons from the neutron EDM
Creators: name: Zhevlakov, Alexey S.
name: Gorchtein, Mikhail
name: Blin, Astrid N. Hiller
name: Gutsche, Thomas
name: Lyubovitskij, Valery E.
Publisher: name: arXiv
Year: 2018
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We provide model-independent bounds on the rates of rare decays $η(η^\prime) \to ππ$ based on experimental limits on the neutron electric dipole moment (nEDM). Starting from phenomenological $η(η^\prime) ππ$ couplings, the nEDM arises at two loop level. The leading-order relativistic ChPT calculation with the minimal photon coupling to charged pions and a proton inside the loops leads to a finite, counter term-free result. This is an improvement upon previous estimates which used approximations in evaluating the two loop contribution and were plagued by divergences. While constraints on the $η(η^\prime) ππ$ couplings in our phenomenological approach are somewhat milder than in the picture with the QCD $θ$-term, our calculation means that whatever the origin of these couplings, The decays $η(η') \to 2 π$ will remain unobservable in the near future.
description: 8 hages, 3 figures
Three Essays on the Economics of Contracts in Labor and Corporate Debt Market
Creators: Yuan, Ding
Publisher: name: Columbia University
Year: 2018
Subjects: Economics
Labor economics
Corporate debt
Wages--Economic aspects

description: Chapter 1 studies wage contracts and their roles in workers’ employment and wage dynamics, as well as the implications on income inequality. I develop an on-the-job search model that allows for different types of wage contracts. Using indirect inference method, I am able to estimate the structural model and evaluate the impact of different productivity elements, including firm productivity, returns to routine task and individual effort. The model is able to capture key measures on worker’s labor market mobility, wage growth and distribution. It also allows me to evaluate the implications of productivity change on income inequality through counterfactual analysis. I show that these productivity elements have different implications on income inequality, and the use of performance based wage contract is an important channel for income polarization at the top percentiles.
      Chapter 2 studies the effect of overtime pay on workers’ working schedule and income. How overtime pay regulations affect the labor market is a controversial yet relatively under- studied topic. In this paper, I study the effect of the revision to statutory overtime pay in 2004 on worker’s income and hours of work. Using monthly panel data on workers’ working hours and income that covers the period of rule change, I find evidence that for workers who gained statutory overtime pay coverage under the new rule, hours and income increased. I also find spillover effects on overtime pay premium and overtime schedule for workers who are not directly affected by the rule change. My results suggest that the standard competitive model does not capture well the labor market for overtime work, and government regulations could reduce labor market frictions.
      Chapter 3 studies debt covenant violations and their effects on corporate innovation. Exploiting the state of debt contract covenant violation and the institutional feature that creditors obtain increased control right of the firm, the paper examines the effect of increased creditor governance well before the state of bankruptcy on corporate innovation. Consistent with the view that increased creditor monitoring has disciplining effect on the managers, I find no significant change in the R&D spending, significant but model decrease in the total patent counts two years forward as well as significant and large positive impact on the citation counts of the patents. The results demonstrate that increased creditor governance is overall beneficial to firm innovation.
Additional file 1 of Uncovering a novel biosynthetic gene cluster for sordarin through genome mining in the fungus Talaromyces adpressus
Creators: name: Xu, Qianqian
name: Ren, Xiaomeng
name: Hu, Linzhen
name: Xu, Qiaoxin
name: Zhang, Xiaodong
name: Deng, Mengyi
name: Ye, Ying
name: Zhang, Yonghui
name: Lu, Yuanyuan
name: Qiao, Yuben
Publisher: name: figshare
Year: 2025
Subjects: subject: Biochemistry
subject: Microbiology
subject: FOS: Biological sciences
subject: Cell Biology
subject: Genetics
subject: Pharmacology
subject: Chemical Sciences not elsewhere classified
subject: Biological Sciences not elsewhere classified
subject: Cancer
subject: Hematology
subject: Infectious Diseases
subject: FOS: Health sciences

description: Supplementary Material 1
Fluctuating Quantum Kinetic Theory
Creators: name: Kirkpatrick, T. R.
name: Belitz, D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We consider a quantum Langevin kinetic equation for a system of fermions. We first derive the Langevin force noise correlation functions in Landau's Fermi-liquid kinetic theory from general considerations. We then use the resulting equation to calculate the equilibrium dynamic structure factor in the collisionless regime at low temperatures. The result is in agreement with the conventional many-body result. We then use the theory to derive both the fluctuating Navier-Stokes equations for a quantum fluid and the fluctuating hydrodynamic equations for fermions in the presence of quenched disorder. We also discuss the modifications needed for the fluctuating hydrodynamic equations to describe an electron fluid with long-ranged interactions, and we prove an H-theorem for the nonlinear Landau kinetic equation.
description: 17pp
An Automatic Interaction Detection Hybrid Model for Bankcard Response Classification
Creators: name: Wang, Yan
name: Ni, Xuelei Sherry
name: Stone, Brian
Publisher: name: arXiv
Year: 2019
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: In this paper, we propose a hybrid bankcard response model, which integrates decision tree based chi-square automatic interaction detection (CHAID) into logistic regression. In the first stage of the hybrid model, CHAID analysis is used to detect the possibly potential variable interactions. Then in the second stage, these potential interactions are served as the additional input variables in logistic regression. The motivation of the proposed hybrid model is that adding variable interactions may improve the performance of logistic regression. To demonstrate the effectiveness of the proposed hybrid model, it is evaluated on a real credit customer response data set. As the results reveal, by identifying potential interactions among independent variables, the proposed hybrid approach outperforms the logistic regression without searching for interactions in terms of classification accuracy, the area under the receiver operating characteristic curve (ROC), and Kolmogorov-Smirnov (KS) statistics. Furthermore, CHAID analysis for interaction detection is much more computationally efficient than the stepwise search mentioned above and some identified interactions are shown to have statistically significant predictive power on the target variable. Last but not least, the customer profile created based on the CHAID tree provides a reasonable interpretation of the interactions, which is the required by regulations of the credit industry. Hence, this study provides an alternative for handling bankcard classification tasks.
title: Complex reflection coefficients applied to steep sloping structures
Creators: name: Büsching, Fritz
Publisher: name: Elektronisch veröffentlicht: 26.04.2016
Year: 2012
Subjects: subject: 620

description: Basierend auf Laboruntersuchungen werden spezifische Phenomene des Wellenbrechens an relativ steilen Böschungen auf variierende Phasenunterschiede zwischen einfallenden und reflektierten Wellen zurückgeführt. Ein komplexer Reflexionskoeffizient umfasst als Betrag das Wellenhöhenverhältnis und als Phase die Phasenverschiebung zwischen einfallender und reflektierter Welle.
Local-Global Context Aware Transformer for Language-Guided Video Segmentation
Creators: name: Liang, Chen
name: Wang, Wenguan
name: Zhou, Tianfei
name: Miao, Jiaxu
name: Luo, Yawei
name: Yang, Yi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: We explore the task of language-guided video segmentation (LVS). Previous algorithms mostly adopt 3D CNNs to learn video representation, struggling to capture long-term context and easily suffering from visual-linguistic misalignment. In light of this, we present Locater (local-global context aware Transformer), which augments the Transformer architecture with a finite memory so as to query the entire video with the language expression in an efficient manner. The memory is designed to involve two components -- one for persistently preserving global video content, and one for dynamically gathering local temporal context and segmentation history. Based on the memorized local-global context and the particular content of each frame, Locater holistically and flexibly comprehends the expression as an adaptive query vector for each frame. The vector is used to query the corresponding frame for mask generation. The memory also allows Locater to process videos with linear time complexity and constant size memory, while Transformer-style self-attention computation scales quadratically with sequence length. To thoroughly examine the visual grounding capability of LVS models, we contribute a new LVS dataset, A2D-S+, which is built upon A2D-S dataset but poses increased challenges in disambiguating among similar objects. Experiments on three LVS datasets and our A2D-S+ show that Locater outperforms previous state-of-the-arts. Further, we won the 1st place in the Referring Video Object Segmentation Track of the 3rd Large-scale Video Object Segmentation Challenge, where Locater served as the foundation for the winning solution. Our code and dataset are available at: https://github.com/leonnnop/Locater
description: Accepted by TPAMI. Code, data: https://github.com/leonnnop/Locater
Conductance channels of a platform molecule on Au(111) probed with shot noise
Creators: name: Mohr, Michael
name: Jasper-Toennies, Torben
name: Frederiksen, Thomas
name: Garcia-Lekue, Aran
name: Ulrich, Sandra
name: Herges, Rainer
name: Berndt, Richard
Publisher: name: arXiv
Year: 2019
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The shot noise of the current $I$ through junctions to single trioxatriangulenium cations (TOTA$^+$) on Au(111) is measured with a low temperature scanning tunneling microscope using Au tips. The noise is significantly reduced compared to the Poisson noise power of $2eI$ and varies linearly with the junction conductance. The data are consistent with electron transmission through a single spin-degenerate transport channel and show that TOTA$^+$ in a Au contact does not acquire an unpaired electron. Ab initio calculations reproduce the observations and show that the current involves the lowest unoccupied orbital of the molecule and tip states close to the Fermi level.
description: 5 pages, 5 figures
Feng Zikai : a biographical and critical study, 1898-1975
Creators: name: Barmé, Geremie
Publisher: name: The Australian National University
Year: 1989
Subjects: subject: Feng, Zikai, 1898-1975

description: This is a study of the life and work of Feng Zikai (1898-1975). While Yu Dafu, a contemporary of Feng's, in the mid-1930s evaluated his essay style as being suffused with a "clear elegance and mystery which at its most subtle is far superior even to his painting", 1 and despite having produced a steady stream of essays up to 1949, Feng Zikai has come to be thought of predominantly as an artist, and due to his particular style of painting, the manhua, as a cartoonist. It is a categorisation th.at was further formalized in Mainland China after 1949 when he was redefined by the requirements of the State as a children's cartoonist, and this is how he was seen until even quite recently. Up to the early 1980s his work was either overlooked in Mainland China, or seen through the distorting glass of Marxist-Leninist literary historians.2 In Taiwan, on the other hand, because Feng chose to remain on the Mainland after 1949, he was shunned.
The Stellar Contents of Intermediate Mass Disk Galaxies in the Virgo Cluster. I. GMOS Spectra
Creators: name: Davidge, T. J.
Publisher: name: arXiv
Year: 2018
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The stellar contents of six intermediate mass early-type disk galaxies in the Virgo cluster are examined using deep long slit spectra. The isophotal and photometric properties of the galaxies at near- and mid-infrared wavelengths are also examined. Characteristic ages and metallicities are found by making comparisons with the strengths of lines measured from model spectra. The light from the central regions of these galaxies at visible/red wavelengths is not dominated by old populations. Rather, the central regions of four galaxies (NGC 4305, NGC 4306, NGC 4497, and NGC 4620) are dominated by populations with ages ~ 1.5 - 3 Gyr. Centrally-concentrated line emission is found in two of the galaxies (NGC 4491 and NGC 4584), and the relative strengths of Halpha and [SII]6746 are consistent with this emission originating in star-forming regions. The disks of these galaxies are dominated by populations that are at least 1 Gyr older than those near the centers, indicating that the quenching of star formation progressed from large radii inwards, and did not occur over a short timescale.
description: To appear in the Astronomical Journal
Role of the scalar field in gravitational lensing
Creators: name: Virbhadra, K. S.
name: Narasimha, D.
name: Chitre, S. M.
Publisher: name: arXiv
Year: 1998
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A static and circularly symmetric lens characterized by mass and scalar charge parameters is constructed. For the small values of the scalar charge to the mass ratio, the gravitational lensing is qualitatively similar to the case of the Schwarzschild lens; however, for large values of this ratio the lensing characteristics are significantly different. The main features are the existence of two or nil Einstein ring(s) and a radial critical curve, formation of two or four images and possibility of detecting three images near the lens for sources located at relatively large angular positions. Such a novel lens may also be treated as a naked singularity lens.
description: 11 pages using A&A LaTex, 3 figures included, misprints corrected, changes in section five, two references added Journal- ref : Astronomy & Astrophysics, 337(1) 1 (1998)
Acquiring elastic properties of thin composite structure from vibrational testing data
Creators: name: Aksenov, Vitalii
name: Vasyukov, Aleksey
name: Beklemysheva, Katerina
Publisher: name: arXiv
Year: 2022
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: The problem of acquiring elastic properties of a composite material from the data of the vibrational testing is considered. The specimen is considered to abide by the linear elasticity laws and subject to viscoelastic damping. The BVP for transverse movement of such a specimen under harmonic load is formulated and solved with finite-element method. The problem of acquiring the elastic parameters is then formulated as a nonlinear least square optimization problem. The usage of the automatic differentiation technique for stable and efficient computation of the gradient and hessian allows to use well-studied first and second order optimization methods, namely Newton and BFGS. The results of the numerical experiments on simulated data are analyzed in order to provide insights for the experiment planning.
Downlink Channel Covariance Matrix Reconstruction for FDD Massive MIMO Systems with Limited Feedback
Creators: name: Li, Kai
name: Li, Ying
name: Cheng, Lei
name: Shi, Qingjiang
name: Luo, Zhi-Quan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The downlink channel covariance matrix (CCM) acquisition is the key step for the practical performance of massive multiple-input and multiple-output (MIMO) systems, including beamforming, channel tracking, and user scheduling. However, this task is challenging in the popular frequency division duplex massive MIMO systems with Type I codebook due to the limited channel information feedback. In this paper, we propose a novel formulation that leverages the structure of the codebook and feedback values for an accurate estimation of the downlink CCM. Then, we design a cutting plane algorithm to consecutively shrink the feasible set containing the downlink CCM, enabled by the careful design of pilot weighting matrices. Theoretical analysis shows that as the number of communication rounds increases, the proposed cutting plane algorithm can recover the ground-truth CCM. Numerical results are presented to demonstrate the superior performance of the proposed algorithm over the existing benchmark in CCM reconstruction.