cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
SU(N) gauge theories in 2+1 dimensions: glueball spectra and k-string tensions
Creators: name: Athenodorou, Andreas
name: Teper, Michael
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We calculate the low-lying glueball spectrum and various string tensions in SU(N) lattice gauge theories in 2+1 dimensions, and extrapolate the results to the continuum limit. We do so for for the range N=2 to N=16 so as to control the N-dependence with a useful precision. We observe a number of striking near-degeneracies in the various J^PC sectors of the glueball spectrum, in particular between C=+ and C=- states. We calculate the string tensions of flux tubes in a number of representations, and provide evidence that the leading correction to the N-dependence of the k-string tensions varies as 1/N rather than 1/N^2, and that the dominant binding of k fundamental flux tubes into a k-string is via pairwise interactions. We comment on the possible implications of our results for the dynamics of these gauge theories.
description: 52 pages, 14 figures
Quantifying spatial, temporal, angular and spectral structure of effective daylight in perceptually meaningful ways
Creators: name: Yu, Cehao
name: Wijntjes, Maarten
name: Eisemann, Elmar
name: Pont, Sylvia
Publisher: name: arXiv
Year: 2022
Subjects: subject: Graphics (cs.GR)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Biological Physics (physics.bio-ph)
subject: Optics (physics.optics)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: We present a method to capture the 7-dimensional light field structure, and translate it into perceptually-relevant information. Our spectral cubic illumination method quantifies objective correlates of perceptually relevant diffuse and directed light components, including their variations over time, space, in color and direction, and the environment's response to sky and sunlight. We applied it 'in the wild', capturing how light on a sunny day differs between light and shadow, and how light varies over sunny and cloudy days. We discuss the added value of our method for capturing nuanced lighting effects on scene and object appearance, such as chromatic gradients.
Myocardial Architecture and Patient Variability in Clinical Patterns of Atrial Fibrillation
Creators: name: Manani, Kishan A.
name: Christensen, Kim
name: Peters, Nicholas S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Tissues and Organs (q-bio.TO)
subject: Biological Physics (physics.bio-ph)
subject: Medical Physics (physics.med-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: Atrial fibrillation (AF) increases the risk of stroke by a factor of four to five and is the most common abnormal heart rhythm. The progression of AF with age, from short self-terminating episodes to persistence, varies between individuals and is poorly understood. An inability to understand and predict variation in AF progression has resulted in less patient-specific therapy. Likewise, it has been a challenge to relate the microstructural features of heart muscle tissue (myocardial architecture) with the emergent temporal clinical patterns of AF. We use a simple model of activation wavefront propagation on an anisotropic structure, mimicking heart muscle tissue, to show how variation in AF behaviour arises naturally from microstructural differences between individuals. We show that the stochastic nature of progressive transversal uncoupling of muscle strands (e.g., due to fibrosis or gap junctional remodelling), as occurs with age, results in variability in AF episode onset time, frequency, duration, burden and progression between individuals. This is consistent with clinical observations. The uncoupling of muscle strands can cause critical architectural patterns in the myocardium. These critical patterns anchor micro-re-entrant wavefronts and thereby trigger AF. It is the number of local critical patterns of uncoupling as opposed to global uncoupling that determines AF progression. This insight may eventually lead to patient specific therapy when it becomes possible to observe the cellular structure of a patient's heart.
description: 5 pages, 4 figures. For supplementary materials please contact Kishan A. Manani at kishan.a.manani@gmail.com
Noncommutative correction to the entropy of charged BTZ black hole
Creators: name: Jurić, Tajron
name: Požar, Filip
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Noncommutative geometry is an established potential candidate for including quantum phenomena in gravitation. We outline the formalism of Hopf algebras and its connection to the algebra of infinitesimal diffeomorphisms. Using a Drinfeld twist we deform spacetime symmetries, algebra of vector fields and differential forms leading to a formulation of noncommutative Einstein equations. We study a concrete example of charged BTZ spacetime and deformations steaming from the so called angular twist. The entropy of the noncommutative charged BTZ black hole is obtained using the brick-wall method. We used a charged scalar field as a probe and obtained its spectrum and density of states via WKB approximation. We provide the method to calculate corrections to the Bekenstein-Hawking entropy in higher orders in WKB, but we present the final result in the lowest WKB order. The result is that even in the lowest order in WKB, the entropy, in general, contains higher powers in $\hbar$, and it has logarithmic corrections, and polynomials of logarithms of the black hole area.
description: 19 pages, typos corrected
Mesoscale shock structure in particulate composites
Creators: name: Ravindran, Suraj
name: Gandhi, Vatsa
name: Lawlor, Barry
name: Ravichandran, Guruswami
Publisher: name: arXiv
Year: 2022
Subjects: subject: Applied Physics (physics.app-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Multiscale experiments in heterogeneous materials and the knowledge of their physics under shock compression are limited. This study examines the multiscale shock response of particulate composites comprised of soda-lime glass particles in a PMMA matrix using full-field high-speed digital image correlation (DIC) for the first time. Normal plate impact experiments, and complementary numerical simulations, are conducted at stresses ranging from $1.1-3.1$ GPa to elucidate the mesoscale mechanisms responsible for the distinct shock structure observed in particulate composites. The particle velocity from the macroscopic measurement at continuum scale shows a relatively smooth velocity profile, with shock thickness decreasing with an increase in shock stress, and the composite exhibits strain rate scaling as the second power of the shock stress. In contrast, the mesoscopic response was highly heterogeneous, which led to a rough shock front and the formation of a train of weak shocks traveling at different velocities. Additionally, the normal shock was seen to diffuse the momentum in the transverse direction, affecting the shock rise and the rounding-off observed at the continuum scale measurements. The numerical simulations indicate that the reflections at the interfaces, wave scattering, and interference of these reflected waves are the primary mechanisms for the observed rough shock fronts.
Client/server computing for retail management systems
Creators: name: Chandrasekaran, Sujatha.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Analysis and design of transition radiation in layered uniaxial crystals using Tandem neural networks
Creators: name: Gao, Xiaoke
name: Zhao, Xiaoyu
name: Huang, Ruoyu
name: Ma, Siyuan
name: Ma, Xikui
name: Dong, Tianyu
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: With the flourishing development of nanophotonics, Cherenkov radiation pattern can be designed to achieve superior performance in particle detection by fine-tuning the properties of metamaterials such as photonic crystals (PCs) surrounding the swift particle. However, the radiation pattern can be sensitive to the geometry and material properties of PCs, such as periodicity, unit thickness, and dielectric fraction, making direct analysis and inverse design difficult. In this article, we propose a systematic method to analyze and design PC-based transition radiation, which is assisted by deep learning neural networks. By matching boundary conditions at the interfaces, Cherenkov-like radiation of multilayered structures can be resolved analytically using the cascading scattering matrix method, despite the optical axes not being aligned with the swift electron trajectory. Once well trained, forward deep learning neural networks can be utilized to predict the radiation pattern without further direct electromagnetic simulations; moreover, Tandem neural networks have been proposed to inversely design the geometry and/or material properties for desired Cherenkov radiation pattern. Our proposal demonstrates a promising strategy for dealing with layered-medium-based Cherenkov radiation detectors, and it can be extended for other emerging metamaterials, such as photonic time crystals.
Profiles of early childhood developmental skills and their relation to early childhood experiences of risk
Creators: name: Palmer, Alyssa
name: Distefano, Rebecca
name: Powell, Tralucia
name: Kalstabakken, Amanda
name: Masten, Ann
name: Banegas, Jasmine
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: Social and Behavioral Sciences
subject: Developmental Psychology
subject: Clinical Psychology
subject: Psychology
subject: FOS: Psychology
subject: Medicine and Health Sciences
subject: Early Childhood Screening
subject: Developmental Profiles
subject: Cognitive Skills
subject: Homelessness
subject: Executive Functioning
subject: Child Protective Services
subject: Early Childhood
subject: Low Income

description: The current study aims to take a person-centered approach to understand cumulative profiles that account for child-specific indicators of socioemotional, cognitive, motor, and academic skills. We will then evaluate how early childhood experiences of low income, Child Protective Service involvement, and the experience of homelessness predict to profiles of child skills.
A comparison of methods for the detection of gravitational waves from unknown neutron stars
Creators: name: Walsh, Sinead
name: Pitkin, Matthew
name: Oliver, Miquel
name: D'Antonio, Sabrina
name: Dergachev, Vladimir
name: Krolak, Andrzej
name: Astone, Pia
name: Bejger, Michal
name: Di Giovanni, Matteo
name: Dorosh, Orest
name: Frasca, Sergio
name: Leaci, Paola
name: Mastrogiovanni, Simone
name: Miller, Andrew
name: Palomba, Cristiano
name: Papa, Maria Alessandra
name: Piccinni, Ornella J.
name: Riles, Keith
name: Sauter, Orion
name: Sintes, Alicia M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Rapidly rotating neutron stars are promising sources of continuous gravitational wave radiation for the LIGO and Virgo interferometers. The majority of neutron stars in our galaxy have not been identified with electromagnetic observations. All-sky searches for isolated neutron stars offer the potential to detect gravitational waves from these unidentified sources. The parameter space of these blind all-sky searches, which also cover a large range of frequencies and frequency derivatives, presents a significant computational challenge. Different methods have been designed to perform these searches within acceptable computational limits. Here we describe the first benchmark in a project to compare the search methods currently available for the detection of unknown isolated neutron stars. We employ a mock data challenge to compare the ability of each search method to recover signals simulated assuming a standard signal model. We find similar performance among the short duration search methods, while the long duration search method achieves up to a factor of two higher sensitivity. We find the absence of second derivative frequency in the search parameter space does not degrade search sensivity for signals with physically plausible second derivative frequencies. We also report on the parameter estimation accuracy of each search method, and the stability of the sensitivity in frequency, frequency derivative and in the presence of detector noise.
description: 16 pages, 11 figures
AIREPAIR: A Repair Platform for Neural Networks
Creators: name: Song, Xidan
name: Sun, Youcheng
name: Mustafa, Mustafa A.
name: Cordeiro, Lucas
Publisher: name: arXiv
Year: 2022
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We present AIREPAIR, a platform for repairing neural networks. It features the integration of existing network repair tools. Based on AIREPAIR, one can run different repair methods on the same model, thus enabling the fair comparison of different repair techniques. We evaluate AIREPAIR with three state-of-the-art repair tools on popular deep-learning datasets and models. Our evaluation confirms the utility of AIREPAIR, by comparing and analyzing the results from different repair techniques. A demonstration is available at https://youtu.be/UkKw5neeWhw.
Bilinear condensate in three-dimensional large-$N_c$ QCD
Creators: name: Karthik, Nikhil
name: Narayanan, Rajamani
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We find clear numerical evidence for a bilinear condensate in three-dimensional QCD in the 't Hooft limit. We use a non-chiral random matrix model to extract the value of the condensate $Σ$ from the low-lying eigenvalues of the massless anti-Hermitian overlap Dirac operator. We estimate $Σ/λ^2 = 0.0042 \pm 0.0004$ in units of the physical 't Hooft coupling.
description: 9 pages, 4 figures
Standing Accretion Shock Instability in the Collapse of a Rotating Stellar Core
Creators: name: Walk, Laurie
name: Foglizzo, Thierry
name: Tamborra, Irene
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Hydrodynamical instabilities, such as the standing accretion-shock instability (SASI), play an essential role in the dynamics of core-collapse supernovae, with observable imprints in the neutrino and gravitational wave signals. Yet, the impact of stellar rotation on the development of SASI is poorly explored. We investigate the conditions favoring the growth of SASI in the presence of rotation through a perturbative analysis. The properties of SASI are compared in two stationary configurations, cylindrical and spherical equatorial, which mainly differ by their advection timescales from the shock to the proto-neutron star surface. Without rotation, the mode $m=1$, corresponding to a one-armed spiral SASI deformation, can be significantly more unstable in the spherical equatorial configuration. In fact, the shorter advection time in the spherical equatorial geometry allows for a larger contribution of the entropic-acoustic coupling from the region of adiabatic compression near the surface of the proto-neutron star. The angular momentum of the collapsing core favors the growth of prograde spiral modes $m=1$ and $m = 2$ in both geometries. Although the growth rate of the spiral instability is systematically faster in spherical geometry, its oscillation frequency is remarkably insensitive to the geometry. Such a contrast with non-rotating flows calls for a deeper understanding of the role of advection in the mechanism of spiral SASI. Our findings suggest that the resonant coupling of acoustic waves with their corotation radius may play a major role in the instability mechanism of collapsing cores with rotation. Elucidating this physical mechanism is essential to interpret the signal from future multi-messenger supernova observations.
description: 15 pages, including 12 figures and 2 appendices. Minor changes in the text; conclusions unchanged. Matches version accepted for publication in Phys. Rev. D
Universal quantum computer based on Carbon Nanotube Rotators
Creators: name: Ezawa, Motohiko
name: Yasunaga, Shun
name: Iizuka, Tetsuya
name: Higo, Akio
name: Mita, Yoshio
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Applied Physics (physics.app-ph)
subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: FOS: Physical sciences

description: We propose a universal quantum computer based on a chain of carbon nanotube rotators where one metallic plate is attached to each rotator. The dynamical variable is the rotational angle $ϕ$. The attached plate connected to ground electrostatically interacts with two fixed plates. Two angle positions $ϕ=0,π$ are made stable by applying a voltage difference between the attached plate and the two fixed plates. We assign $ϕ=0$ and $π$ to the qubit states $|0\rangle$ and $|1\rangle $. Then, considering a chain of rotators, we construct the arbitrary phase-shift gate, the NOT gate and the Ising gate, which constitute a set of universal quantum gates. They are executed by controlling the voltage between various plates.
description: 7 pages, 5 figures
Vacuum Measurements and Quantum State Reconstruction of Phonons
Creators: name: Lv, Dingshun
name: An, Shuoming
name: Um, Mark
name: Zhang, Junhua
name: Zhang, Jing -Ning
name: Kim, M. S.
name: Kim, Kihwan
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: A quantum state is fully characterized by its density matrix or equivalently by its quasiprobabilities in phase space. A scheme to identify the quasiprobabilities of a quantum state is an important tool in the recent development of quantum technologies. Based on our highly efficient vacuum measurement scheme, we measure the quasiprobability $Q$-function of the vibrational motion for a \Yb ion {\it resonantly} interacting with its internal energy states. This interaction model is known as the Jaynes-Cummings model which is one of the fundamental models in quantum electrodynamics. We apply the capability of the vacuum measurement to study the Jaynes-Cummings dynamics, where the Gaussian peak of the initial coherent state is known to bifurcate and rotate around the origin of phase space. They merge at the so-called revival time at the other side of phase space. The measured $Q$-function agrees with the theoretical prediction. Moreover, we reconstruct the Wigner function by deconvoluting the $Q$-function and observe the quantum interference in the Wigner function at half of the revival time, where the vibrational state becomes nearly disentangled from the internal energy states and forms a superposition of two composite states. The scheme can be applied to other physical setups including cavity or circuit-QED and optomechanical systems.
description: 6 pages, 4 figures
Unitary forms for holomorphic vertex operator algebras of central charge $24$
Creators: name: Lam, Ching Hung
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics
subject: 17B69

description: We prove that all holomorphic vertex operator algebras of central charge $24$ with non-trivial weight one subspaces are unitary. The main method is to use the orbifold construction of a holomorphic VOA $V$ of central charge $24$ directly from a Niemeier lattice VOA $V_N$. We show that it is possible to extend the unitary form for the lattice VOA $V_N$ to the holomorphic VOA $V$ by using the orbifold construction and some information of the automorphism group $\mathrm{Aut}(V)$.
VISUALIZING THE ACCELERATION OF RARE EARTH ELEMENTS MINING IN KACHIN, MYANMAR: A POLYSPECTRAL SPATIAL DATABASE
Creators: name: Geniesse, Joseph
Publisher: name: University of Chicago
Year: 2023

description: Rare earth elements (REEs) are at the center of the transition to renewable energy. However, this position has justified their extraction despite severe environmental consequences. Historically, China has served as the primary source of global REEs, but in the last decade Chinese mining interests have expanded into Myanmar. The China-Myanmar border has rapidly become a frontier of REEs extraction, but this growth is not well understood. To gain insight into the rate of the expansion of REEs mining in Myanmar, a convolutional neural network was trained to detect sights of extraction from satellite data of the region. The model demonstrated an exponential increase in REEs mining and the methodology outlined in this work and has the potential to strengthen understanding of extraction in inaccessible areas.
The Method in Madness: A Processual Account of a South Korean Conspiracy Theory “Community”
Creators: name: Taewon, Min
Publisher: name: University of Chicago
Year: 2022
Subjects: subject: Internet
subject: Conspiracy Theory
subject: Echo Chamber
subject: Processual Sociology
subject: Online Community
subject: South Korea

description: Why did the South Korean conspiracy theory on the 2020 general election fail to garner political influence like QAnon and anti-vaccine conspiracy theories? This paper argues that answering this question requires a processual approach to social phenomena. Appreciating a conspiracy theory “community” as a gathering of multiple entities constantly recreated in relation to others is crucial for explaining the failure of the Wuhan Gallery, a South Korean “community” that gave birth to the conspiracy theory. Even though the claims of election fraud gained traction after the landslide loss, other South Korean online “communities” criticized the conspiracy theory and engaged with the Wuhan Gallery with mockery involving rhetoric against the elderly. Wuhan Gallery responded by banning users that seemingly came from other “communities” as trolls, which hindered different readings of the conspiracy theory and its relationship with politicians. Critics of conservative YouTubers and politicians were stigmatized as trolls, making the conspiracy theory on the election fraud no different from failed conspiracy theories of the past. The result of the research implies that the conspiracy theory “community,” as well as discourse on conspiracy theory, was constantly shifting over time and that social factors play a crucial role in the rise or fall of a conspiracy theory. Furthermore, the trajectory of the conspiracy theory “community” demonstrates how users in South Korean cyberspace constantly misrecognize what is taking place by neglecting the processual character of the internet and social entities and underlines the importance of a processual approach in social sciences.
Predictions of the atmospheric composition of GJ 1132b
Creators: name: Schaefer, Laura
name: Wordsworth, Robin
name: Berta-Thompson, Zachory
name: Sasselov, Dimitar
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: GJ 1132 b is a nearby Earth-sized exoplanet transiting an M dwarf, and is amongst the most highly characterizable small exoplanets currently known. In this paper we study the interaction of a magma ocean with a water-rich atmosphere on GJ 1132b and determine that it must have begun with more than 5 wt% initial water in order to still retain a water-based atmosphere. We also determine the amount of O2 that can build up in the atmosphere as a result of hydrogen dissociation and loss. We find that the magma ocean absorbs at most ~10% of the O2 produced, whereas more than 90% is lost to space through hydrodynamic drag. The most common outcome for GJ 1132 b from our simulations is a tenuous atmosphere dominated by O2, although for very large initial water abundances atmospheres with several thousands of bars of O2 are possible. A substantial steam envelope would indicate either the existence of an earlier H2 envelope or low XUV flux over the system's lifetime. A steam atmosphere would also imply the continued existence of a magma ocean on GJ 1132 b. Further modeling is needed to study the evolution of CO2 or N2-rich atmospheres on GJ 1132 b.
description: 14 pages, 11 figures, accepted at ApJ
Recommending on graphs: a comprehensive review from a data perspective
Creators: name: Zhang, Lemei
name: Liu, Peng
name: Gulla, Jon Atle
Publisher: name: arXiv
Year: 2022
Subjects: subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: Recent advances in graph-based learning approaches have demonstrated their effectiveness in modelling users' preferences and items' characteristics for Recommender Systems (RSS). Most of the data in RSS can be organized into graphs where various objects (e.g., users, items, and attributes) are explicitly or implicitly connected and influence each other via various relations. Such a graph-based organization brings benefits to exploiting potential properties in graph learning (e.g., random walk and network embedding) techniques to enrich the representations of the user and item nodes, which is an essential factor for successful recommendations. In this paper, we provide a comprehensive survey of Graph Learning-based Recommender Systems (GLRSs). Specifically, we start from a data-driven perspective to systematically categorize various graphs in GLRSs and analyze their characteristics. Then, we discuss the state-of-the-art frameworks with a focus on the graph learning module and how they address practical recommendation challenges such as scalability, fairness, diversity, explainability and so on. Finally, we share some potential research directions in this rapidly growing area.
description: Accepted by UMUAI
Non-equilibrium quantum phase transition via entanglement decoherence dynamics
Creators: name: Lin, Yu-Chen
name: Yang, Pei-Yun
name: Zhang, Wei-Min
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We investigate the decoherence dynamics of continuous variable entanglement as the system-environment coupling strength varies from the weak-coupling to the strong-coupling regimes. Due to the existence of localized modes in the strong-coupling regime, the system cannot approach equilibrium with its environment, which induces a nonequilibrium quantum phase transition. We analytically solve the entanglement decoherence dynamics for an arbitrary spectral density. The nonequilibrium quantum phase transition is demonstrated as the system-environment coupling strength varies for all the Ohmic-type spectral densities. The 3-D entanglement quantum phase diagram is obtained.
description: 16 pages, 3 figures
MetaFlow: a Scalable Metadata Lookup Service for Distributed File Systems in Data Centers
Creators: name: Sun, Peng
name: Wen, Yonggang
name: Duong, Ta Nguyen Binh
name: Xie, Haiyong
Publisher: name: arXiv
Year: 2016
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: In large-scale distributed file systems, efficient meta- data operations are critical since most file operations have to interact with metadata servers first. In existing distributed hash table (DHT) based metadata management systems, the lookup service could be a performance bottleneck due to its significant CPU overhead. Our investigations showed that the lookup service could reduce system throughput by up to 70%, and increase system latency by a factor of up to 8 compared to ideal scenarios. In this paper, we present MetaFlow, a scalable metadata lookup service utilizing software-defined networking (SDN) techniques to distribute lookup workload over network components. MetaFlow tackles the lookup bottleneck problem by leveraging B-tree, which is constructed over the physical topology, to manage flow tables for SDN-enabled switches. Therefore, metadata requests can be forwarded to appropriate servers using only switches. Extensive performance evaluations in both simulations and testbed showed that MetaFlow increases system throughput by a factor of up to 3.2, and reduce system latency by a factor of up to 5 compared to DHT-based systems. We also deployed MetaFlow in a distributed file system, and demonstrated significant performance improvement.
description: in IEEE Transactions on Big Data 2016
Low coherence interferometric detection of the spectral dependence of the retro-reflection coefficient of an anti-reflective coated interface
Creators: name: Lequime, Michel
name: Khan, Imran
name: Zerrad, Myriam
name: Amra, Claude
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The measurement of very low reflection coefficients of anti-reflective coated interfaces has become a key issue for the realization of precision instruments such as the giant interferometers used for the detection of gravitational waves. We propose in this paper a method, based on low coherence interferometry and balanced detection, which not only allows to obtain the spectral dependence of this reflection coefficient in amplitude and phase, with a sensitivity of the order of 0.1 ppm and a spectral resolution of 0.2 nm, but also to eliminate any spurious influence related to the possible presence of uncoated interfaces. This method also implements a data processing similar to that used in Fourier transform spectrometry. After establishing the formulas that control the accuracy and the signal-to-noise ratio of this method, we present the results that provide a complete demonstration of its successful operation in various experimental conditions.
description: 27 pages, 15 figures
Polarization-mediated Debye-screening of surface potential fluctuations in dual-channel AlN/GaN high electron mobility transistors
Creators: name: Deen, David A.
name: Miller, Ross
name: Osinsky, Andrei
name: Downey, Brian P.
name: Storm, David F.
name: Meyer, David J.
name: Katzer, D. Scott
name: Nepal, Neeraj
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: A dual-channel AlN/GaN/AlN/GaN high electron mobility transistor (HEMT) architecture is proposed, simulated, and demonstrated that suppresses gate lag due to surface-originated trapped charge. Dual two-dimensional electron gas (2DEG) channels are utilized such that the top 2DEG serves as an equipotential that screens potential fluctuations resulting from surface trapped charge. The bottom channel serves as the transistor's modulated channel. Two device modeling approaches have been performed as a means to guide the device design and to elucidate the relationship between the design and performance metrics. The modeling efforts include a self-consistent Poisson-Schrodinger solution for electrostatic simulation as well as hydrodynamic three-dimensional device modeling for three-dimensional electrostatics, steady-state, and transient simulations. Experimental results validated the HEMT design whereby homo-epitaxial growth on free-standing GaN substrates and fabrication of same-wafer dual-channel and recessed-gate AlN/GaN HEMTs have been demonstrated. Notable pulsed-gate performance has been achieved by the fabricated HEMTs through a gate lag ratio of 0.86 with minimal drain current collapse while maintaining high levels of dc and rf performance.
description: 30 pages (pre-print), 13 figures. arXiv admin note: text overlap with arXiv:1508.07794
External Compton Scattering in Blazar Jets and the Location of the Gamma-Ray Emitting Region
Creators: name: Finke, Justin D.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: I study the location of the $γ$-ray emission in blazar jets by creating a Compton-scattering approximation valid for all anisotropic radiation fields in the Thomson through Klein-Nishina regimes, which is highly accurate and can speed up numerical calculations by up to a factor $\sim10$. I apply this approximation to synchrotron self-Compton, and external Compton-scattering of photons from the accretion disk, broad-line region (BLR), and dust torus. I use a stratified BLR model and include detailed Compton-scattering calculations of a spherical and flattened BLR. I create two dust torus models, one where the torus is an annulus, and one where it is an extended disk. I present detailed calculations of the photoabsorption optical depth using my detailed BLR and dust torus models, including the full angle dependence. I apply these calculations to the emission from a relativistically moving blob traveling through these radiation fields. The ratio of $γ$-ray to optical flux produces a predictable pattern that could help locate the $γ$-ray emission region. I show that the bright flare from 3C 454.3 in 2010 November detected by the Fermi Large Area Telescope is unlikely to originate from a single blob inside the BLR since it moves outside the BLR in a time shorter than the flare duration, although emission by multiple blobs inside the BLR is possible; and $γ$-rays are unlikely to originate from outside the BLR from scattering of photons from an extended dust torus, since then the cooling timescale would be too long to explain the observed short variability.
description: Accepted by ApJ. 22 pages, 19 Figures, 5 Tables
MPEC 2023-S45 : 2023 SD
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 SD

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Generalised agent for solving higher board states of tic tac toe using Reinforcement Learning
Creators: name: Kalra, Bhavuk
Publisher: name: arXiv
Year: 2022
Subjects: subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Tic Tac Toe is amongst the most well-known games. It has already been shown that it is a biased game, giving more chances to win for the first player leaving only a draw or a loss as possibilities for the opponent, assuming both the players play optimally. Thus on average majority of the games played result in a draw. The majority of the latest research on how to solve a tic tac toe board state employs strategies such as Genetic Algorithms, Neural Networks, Co-Evolution, and Evolutionary Programming. But these approaches deal with a trivial board state of 3X3 and very little research has been done for a generalized algorithm to solve 4X4,5X5,6X6 and many higher states. Even though an algorithm exists which is Min-Max but it takes a lot of time in coming up with an ideal move due to its recursive nature of implementation. A Sample has been created on this link \url{https://bk-tic-tac-toe.herokuapp.com/} to prove this fact. This is the main problem that this study is aimed at solving i.e providing a generalized algorithm(Approximate method, Learning-Based) for higher board states of tic tac toe to make precise moves in a short period. Also, the code changes needed to accommodate higher board states will be nominal. The idea is to pose the tic tac toe game as a well-posed learning problem. The study and its results are promising, giving a high win to draw ratio with each epoch of training. This study could also be encouraging for other researchers to apply the same algorithm to other similar board games like Minesweeper, Chess, and GO for finding efficient strategies and comparing the results.
description: 29 pages, 20 figures, 2022 Seventh International Conference on Parallel, Distributed and Grid Computing(PDGC)
MPEC 2023-S46 : 2023 SE
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 SE

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Conformal $(p,q)$ supergeometries in two dimensions
Creators: name: Kuzenko, Sergei M.
name: Raptakis, Emmanouil S. N.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We propose a superspace formulation for conformal $(p,q)$ supergravity in two dimensions as a gauge theory of the superconformal group $\mathsf{OSp}_0 (p|2; {\mathbb R} ) \times \mathsf{OSp}_0 (q|2; {\mathbb R} )$ with a flat connection. Upon degauging of certain local symmetries, this conformal superspace is shown to reduce to a conformally flat $\mathsf{SO}(p) \times \mathsf{SO}(q)$ superspace with the following properties: (i) its structure group is a direct product of the Lorentz group and $\mathsf{SO}(p) \times \mathsf{SO}(q)$; and (ii) the residual local scale symmetry is realised by super-Weyl transformations with an unconstrained real parameter. As an application of the formalism, we describe ${\cal N}$-extended AdS superspace as a maximally symmetric supergeometry in the $p=q \equiv \cal N$ case. If at least one of the parameters $p$ or $q$ is even, alternative superconformal groups and, thus, conformal superspaces exist. In particular, if $p = 2n$, a possible choice of the superconformal group is $\mathsf{SU}(1,1|n) \times \mathsf{OSp}_0 (q|2; {\mathbb R} )$, for $n \neq 2$, and $\mathsf{PSU}(1,1|2) \times \mathsf{OSp}_0 (q|2; {\mathbb R} )$, when $n=2$. In general, a conformal superspace formulation is associated with a supergroup $ G = G_L \times G_R$, where the simple supergroups $G_L$ and $G_R$ can be any of the extended superconformal groups, which were classified by Günaydin, Sierra and Townsend. Degauging the corresponding conformal superspace leads to a conformally flat $H_L \times H_R$ superspace, where $H_L $ ($H_R$) is the $R$-symmetry subgroup of $G_L$ ($G_R$). Additionally, for the $p,q \leq 2$ cases we propose composite primary multiplets which generate the Gauss-Bonnet invariant and supersymmetric extensions of the Fradkin-Tseytlin term.
description: 42 pages; V2: 49 pages, references, comments and a new appendix added
The Effect of Tides on the Population of PN from Interacting Binaries
Creators: name: Madappatt, Niyas
name: De Marco, Orsola
name: Villaver, Eva
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We have used the tidal equations of Zahn to determine the maximum orbital distance at which companions are brought into Roche lobe contact with their giant primary, when the primary expands during the giant phases. This is a key step when determining the rates of interaction between giants and their companions. Our stellar structure calculations are presented as maximum radii reached during the red and asymptotic giant branch (RGB and AGB, respectively) stages of evolution for masses between 0.8 and 4.0 Mo (Z=0.001 - 0.04) and compared with other models to gauge the uncertainty on radii deriving from details of these calculations. We find overall tidal capture distances that are typically 1-4 times the maximum radial extent of the giant star, where companions are in the mass range from 1 Jupiter mass to a mass slightly smaller than the mass of the primary. We find that only companions at initial orbital separations between ~320 and ~630 Ro will be typically captured into a Roche lobe-filling interaction or a common envelope on the AGB. Comparing these limits with the period distribution for binaries that will make PN, we deduce that in the standard scenario where all ~1-8 Mo stars make a PN, at most 2.5 per cent of all PN should have a post-common envelope central star binary, at odds with the observational lower limit of 15-20 per cent. The observed over-abundance of post-interaction central stars of PN cannot be easily explained considering the uncertainties. We examine a range of explanations for this discrepancy.
description: 19 pages, 16 figures, accepted by Monthly Notices of the Royal Astronomical Society
The roles of advisors in Chinese volunteer tourism sending organisations: Professional, supporter, influencer
Creators: name: Chen, Guoyang
name: Smith, Karen
name: Schott, Christian
Publisher: name: Open Access Te Herenga Waka-Victoria University of Wellington
Year: 2023
Subjects: subject: 159999 Commerce, Management, Tourism and Services not elsewhere classified
subject: FOS: Economics and business

description: Volunteer tourism has received much attention from academics, but volunteer tourism staff are under-researched, as is the Chinese volunteer tourism context. This doctorial study aims to understand the roles of Chinese volunteer tourism advisors and the factors which influence their role identities. Semi-structured interviews with advisors identified three over-arching roles. First, the advisor as a professional, including clerk, advisor, coordinator, project leader, project developer and customer service roles. Second, the advisor as supporter, encompassing roles as firefighter, gatekeeper, mentor and friend. Third, the advisor as influencer, including key opinion leader, promotor,learner, entrepreneur and the Chinese concept of Gong yi zhe (public-spirited people). The research will contribute to the knowledge of volunteer tourism staff and roles in tourism and Chinese contexts.
MPEC 2023-S47 : 2023 SF
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 SF

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Short fans and the 5/6 bound for line graphs
Creators: name: Cranston, Daniel W.
name: Rabern, Landon
Publisher: name: arXiv
Year: 2016
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C15

description: In 2011, the second author conjectured that every line graph $G$ satisfies $χ(G)\le \max\{ω(G),\frac{5Δ(G)+8}{6}\}$. This conjecture is best possible, as shown by replacing each edge in a 5-cycle by $k$ parallel edges, and taking the line graph. In this paper we prove the conjecture. We also develop more general techniques and results that will likely be of independent interest, due to their use in attacking the Goldberg--Seymour conjecture.
description: 28 pages, 5 figures
Computational modelling of passive transport of functionalized nanoparticles
Creators: name: Moreno-Chaparro, Daniela
name: Moreno, Nicolas
name: Balboa-Usabiaga, Florencio
name: Ellero, Marco
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Functionalized nanoparticles (NPs) are complex objects present in a variety of systems ranging from synthetic grafted nanoparticles to viruses. The morphology and number of the decorating groups can vary widely between systems. Thus, the modelling of functionalized NPs typically considers simplified spherical objects as a first-order approximation. At the nanoscale label, complex hydrodynamic interactions are expected to emerge as the morphological features of the particles change, and they can be further amplified when the NPs are confined or near walls. Direct estimation of these variations can be inferred via diffusion coefficients of the NPs. However, the evaluation of the coefficients requires an improved representation of the NPs morphology to reproduce important features hidden by simplified spherical models. Here, we characterize the passive transport of free and confined functionalized nanoparticles using the Rigid Multi-Blob (RMB) method. The main advantage of RMB is its versatility to approximate the mobility of complex structures at the nanoscale with significant accuracy and reduced computational cost. In particular, we investigate the effect of functional groups distribution, size and morphology over nanoparticle translational and rotational diffusion. We identify that the presence of functional groups significantly affects the rotational diffusion of the nanoparticles, moreover, the morphology of the groups and number induce characteristic mobility reduction compared to non-functionalized nanoparticles. Confined NPs also evidenced important alterations in their diffusivity, with distinctive signatures in the off-diagonal contributions of the rotational diffusion. These results can be exploited in various applications, including biomedical, polymer nanocomposite fabrication, drug delivery, and imaging
Anatomy of open-boundary bulk in multiband non-Hermitian systems
Creators: name: Fu, Yongxu
name: Zhang, Yi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Although the non-Bloch band theory is a milestone in elaborating bulk energy bands of non-Hermitian systems under the open-boundary condition (OBC), vital issues related to multivalued functions of non-Hermitian energy bands remain unsolved. In this paper, we anatomize the bulk properties of one-dimensional multiband non-Hermitian systems under OBC. We put forward the energy-band branches (EBBs) to settle the multivalued functions of non-Hermitian energy bands, which become gapped or gapless corresponding to disconnected or connected EBBs in the complex energy plane, where the branch points and branch cuts play a crucial role. We clarify the precise significance of the non-Hermitian skin effect, which illustrates the asymptotic behavior of EBB eigenstates (bulk eigenstates) in the deep bulk and compensates previous non-Bloch band theory. We also obtain a general expression of open-boundary Green's functions based on such EBBs and generalized Brillouin zones, useful for studies on non-Hermitian dynamical evolution.
description: 18 pages, 8 figures