cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Quantum Monte Carlo Study of the Quasi-One-Dimensional Superconductivity
Creators: name: Aonuma, Tohru
name: Fuseya, Yuki
name: Ogata, Masao
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We report on the result of quantum Monte Carlo simulation of quasi-one-dimensional electron systems at 1/4-filling, considering organic superconductors such as TMTSF- and TMTTF-salts. We focus on the effect of dimensionality (interchain coupling) on superconducting fluctuation. First we consider Hubbard model which includes only on-site repulsion U. We find that the increase of interchain coupling enhances superconducting susceptibility, although it deforms the nested Fermi surface and suppresses the spin susceptibility. Next we consider an extended Hubbard model which includes nearest-neighbor repulsion V . In this case we consider the competition between different symmetries of electron pairing, d_{x^2-y^2} - and d_xy-wave symmetry, and find that the particle-particle interaction vertex for d_{x^2-y^2}-wave pairing is no longer attractive even in the region where nesting condition still holds. On the other hand, the interaction vertex for d_xy-wave pairing persists to be attractive. The obtained results for the Hubbard model show qualitative agreement with recent renormalization group study, and have the possibility of accounting for the recent experimental result of (TMTTF)2SbF6, which exhibits a wider superconducting phase than the previous studies.
description: 8 pages, 14 figures
Cusps on cosmic superstrings with junctions
Creators: name: Davis, Anne-Christine
name: Nelson, William
name: Rajamanoharan, Senthooran
name: Sakellariadou, Mairi
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The existence of cusps on non-periodic strings ending on D-branes is demonstrated and the conditions, for which such cusps are generic, are derived. The dynamics of F-, D-string and FD-string junctions are investigated. It is shown that pairs of FD-string junctions, such as would form after intercommutations of F- and D-strings, generically contain cusps. This new feature of cosmic superstrings opens up the possibility of extra channels of energy loss from a string network. The phenomenology of cusps on such cosmic superstring networks is compared to that of cusps formed on networks of their field theory analogues, the standard cosmic strings.
description: 22 pages, 5 figures
The effect of a self-instructional module on the level of questions posed by nursing instructors during post-clinical conferences
Creators: name: Craig, Jennifer
Publisher: name: University of British Columbia
Year: 2010

description: The effect of a self-instructional module on the level of questions posed by nursing instructors during post-clinical conferences. The education of many clinical nursing instructors prepared them to nurse, not to teach. When conducting post-clinical conferences, the nursing instructor is expected to help students integrate their experiences and relate them to classroom teaching and nursing theory. One of the many skills required to do this, is the posing of thought-provoking questions. The purpose of this study was to prepare, and evaluate the effectiveness of, educational materials for clinical nursing instructors in order that they may improve their questioning skills during post-clinical conferences. A self-instructional learning module was designed to teach nursing instructors how to ask questions directed toward the higher levels of cognitive processes. A question classification scheme based on Bloom's Taxonomy was developed. Learning activities included reading, identification of questions, generation of questions, and analysis of questions asked during a recording of one of the learner's post-clinical conferences. The question addressed in the experimental phase of this study was, "Can the level of questions asked by nursing instructors during post- clinical conferences be raised by the study of a specific self-instructional module?" The design of the study was a pretest - posttest control group design. The subjects were fourteen nursing instructors representing four faculties of nursing. Six instructors formed the experimental group and eight, the control group. The independent variable was the self-instructional module. The dependent variable was the percentage of high level questions asked by nursing instructors. High level questions were considered to be those that addressed the application level, or above, of Bloom's Taxonomy. Data were obtained on half-hour audiotapes of post-clinical conferences. All questions asked by both instructors and students were transcribed into written form and coded according to the classification scheme developed for this study. When the gain scores of the experimental group were compared with those of the control group, a significant difference was found. It was concluded that the self-instructional module had been effective in raising the level of questions asked. A second hypothesis to test the relation between the level of questions asked by instructors and the level of questions asked by their students, was abandoned due to an insufficient number of student questions.
Unidirectional coupling of a quantum emitter to a subwavelength grating waveguide with engineered stationary inflection point
Creators: name: Volkov, Ilya. A.
name: Savelev, Roman S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: In this work, we propose an approach for the design of a waveguide structure that allows for efficient and highly asymmetric coupling of the quantum sources with circularly polarized transition dipole moments to the guided mode of the structure. The approach is based on the mixing of the two quasi-degenerate modes of a periodic waveguide with an auxiliary single-mode waveguide leading to the formation of the dispersion with a stationary inflection point and consequently to the high coupling efficiency of this mode with a dipole source. We show that the distribution of the field polarization inside the waveguide is relatively homogeneous maintaining the circular polarization in a large area. Consequently, this leads to a high degree of tolerance of the coupling asymmetry and strength to the position of the quantum emitter. We believe, that our results will extend the variety of designs of the efficient chiral nanophotonic interfaces based on planar semiconductor nanostructures.
description: Main text: 20 pages, 5 figures; Supporting information: 13 pages, 5 figures
Elastic energy of multi-component solid solutions and strain origins of phase stability in high-entropy alloys
Creators: name: Kamachali, Reza Darvishi
name: Wang, Lei
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: The elastic energy of mixing for multi-component solid solutions is derived by generalizing Eshelby's sphere-in-hole model for binary alloys. By surveying the dependence of the elastic energy on chemical composition and lattice misfit, we propose a lattice strain coefficient λ*. Applying to several high-entropy alloys and superalloys, we found that most solid solution alloys are stable when λ*<0.16, analogous to the Hume-Rothery atomic-size rule for binary alloys. We also reveal that the polydispersity index δ, frequently used for describing strain in multi-component alloys, is directly related to the elastic energy (e) with e=qδ^2, q being an elastic constant. Furthermore, the effects of (i) the number and (ii) the atomic-size distribution of constituting elements on the phase stability of high-entropy alloys were quantified. The present derivations open for richer considerations of elastic effects in high-entropy alloys, offering immediate support for quantitative assessments of their thermodynamic properties and studying related strengthening mechanisms.
description: 12 pages, 7 figures + graphical abstract, original derivations
The extremes of neutron richness
Creators: name: Marqués, F. Miguel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A neutron star is pictured as a gigantic nucleus overwhelmed by the number of neutrons, unlike real atomic nuclei, that have a similar number of neutrons and protons. Is this true? What if we could find, or create nuclei without protons? How far can we go in neutron richness? Our common sense tells us that these neutral nuclei should not exist, but if they do they would change our knowledge on neutron stars, on the properties of nuclei in general, and ultimately on the nucleon-nucleon interaction itself, the building block of matter. This huge potential impact has pushed some ambitious nuclear physicists to search for them since the 1960s. The first positive hints appeared only in the XXI century, and nowadays several collaborations are trying to corner these weird objects and give a definite answer to this crucial question. In this \edit{review} we will go through this fascinating quest, that started with humble experiments and has now reached a stage of ambitious and sophisticated projects, both in experiment and theory.
description: 21 pages, 15 figures, lecture given at the Third Pisa Summer School, "Rewriting Nuclear Physics Textbooks: one more step forward", University of Pisa (Italy), July 22-26, 2019
Graph Capsule Aggregation for Unaligned Multimodal Sequences
Creators: name: Wu, Jianfeng
name: Mai, Sijie
name: Hu, Haifeng
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: Humans express their opinions and emotions through multiple modalities which mainly consist of textual, acoustic and visual modalities. Prior works on multimodal sentiment analysis mostly apply Recurrent Neural Network (RNN) to model aligned multimodal sequences. However, it is unpractical to align multimodal sequences due to different sample rates for different modalities. Moreover, RNN is prone to the issues of gradient vanishing or exploding and it has limited capacity of learning long-range dependency which is the major obstacle to model unaligned multimodal sequences. In this paper, we introduce Graph Capsule Aggregation (GraphCAGE) to model unaligned multimodal sequences with graph-based neural model and Capsule Network. By converting sequence data into graph, the previously mentioned problems of RNN are avoided. In addition, the aggregation capability of Capsule Network and the graph-based structure enable our model to be interpretable and better solve the problem of long-range dependency. Experimental results suggest that GraphCAGE achieves state-of-the-art performance on two benchmark datasets with representations refined by Capsule Network and interpretation provided.
Photovoltaic Hall effect in two-dimensional electron gas: Kinetic theory
Creators: name: Durnev, M. V.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study theoretically transverse photoconductivity induced by circularly polarized radiation, i.e. the photovoltaic Hall effect, and linearly polarized radiation causing intraband optical transitions in two-dimensional electron gas (2DEG). We develop a microscopic theory of these effects based on analytical solution of the Boltzmann equation for arbitrary electron spectrum and scattering mechanism. We calculate the transverse photoconductivity of 2DEG with parabolic and linear dispersion for short-range and Coulomb scatterers at different temperatures. We show that the transverse electric current is significantly enhanced at frequencies comparable to the inverse energy relaxation time, whereas at higher frequencies the excitation spectrum and the direction of current depend on the scattering mechanism. We also analyse the effect of thermalization processes caused by electron-electron collisions on the photoconductivity.
description: 8 pages, 4 figures
Non-Debye relaxations: The characteristic exponent in the excess wings model
Creators: name: Górska, K.
name: Horzela, A.
name: Pogány, T. K.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The characteristic (Laplace or Lévy) exponents uniquely characterize infinitely divisible probability distributions. Although of purely mathematical origin they appear to be uniquely associated with the memory functions present in evolution equations which govern the course of such physical phenomena like non-Debye relaxations or anomalous diffusion. Commonly accepted procedure to mimic memory effects is to make basic equations time smeared, i.e., nonlocal in time. This is modeled either through the convolution of memory functions with those describing relaxation/diffusion or, alternatively, through the time smearing of time derivatives. Intuitive expectations say that such introduced time smearings should be physically equivalent. This leads to the conclusion that both kinds of so far introduced memory functions form a "twin" structure familiar to mathematicians for a long time and known as the Sonine pair. As an illustration of the proposed scheme we consider the excess wings model of non-Debye relaxations, determine its evolution equations and discuss properties of the solutions.
Inverse Square-Root Field Dependence of Conductivity in Organic Field-Effect Transistors
Creators: name: Wei, J. H.
name: Gao, Y. L.
name: Wang, X. R.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: This paper has been withdrawn by the author.
description: This paper has been withdrawn
Supplementary document for Optically Driven Ultraviolet-C Glowing from An In-Situ Trapping-Detrapping Approach - 7199954.pdf
Creators: name: Wang, Yi
name: Zhou, Pengshang
name: Lin, Hengwei
name: Du, Jiaren
Publisher: name: Optica Publishing Group
Year: 2024
Subjects: Uncategorized

description: Supplementary information.
Eccentricities, fluctuations and A-dependence of elliptic and triangular flows in heavy-ion collisions
Creators: name: Eyyubova, G. Kh.
name: Korotkikh, V. L.
name: Snigirev, A. M.
name: Zabrodin, E. E.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: A simple geometrical model with event-by-event fluctuations is suggested to study elliptical and triangular eccentricities in the initial state of relativistic heavy-ion collisions. This model describes rather well the ALICE and ATLAS data for Pb+Pb collisions at center-of-mass energy $\sqrt{s_{NN}} = 5.02$~TeV per nucleon pair, assuming that the second, $v_2$, and third, $v_3$, harmonics of the anisotropic flow are simply linearly proportional to the eccentricities $\varepsilon_2$ and $\varepsilon_3$, respectively. We show that the eccentricity $\varepsilon_3$ has a pure fluctuation origin and is substantially dependent on the size of the overlap area only, while the eccentricity $\varepsilon_2$ is mainly related to the average collision geometry. Elliptic flow, therefore, is weakly dependent on the event-by-event fluctuations everywhere except of the very central collisions 0--2%, whereas triangular flow is mostly determined by the fluctuations. The scaling dependence of the magnitude of the flow harmonics on atomic number, $v_n \propto A^{-1/3}$, is predicted for this centrality interval.
description: Further development and extension of ideas discussed in arXiv:2007.04850. Accepted for publication in J. of Physics G: Nucl. and Part. Physics
Entanglement Cost of Nonlocal Measurements
Creators: name: Bandyopadhyay, Somshubhro
name: Brassard, Gilles
name: Kimmel, Shelby
name: Wootters, William K.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: For certain joint measurements on a pair of spatially separated particles, we ask how much entanglement is needed to carry out the measurement exactly. For a class of orthogonal measurements on two qubits with partially entangled eigenstates, we present upper and lower bounds on the entanglement cost. The upper bound is based on a recent result by D. Berry [Phys. Rev. A 75, 032349 (2007)]. The lower bound, based on the entanglement production capacity of the measurement, implies that for almost all measurements in the class we consider, the entanglement required to perform the measurement is strictly greater than the average entanglement of its eigenstates. On the other hand, we show that for any complete measurement in d x d dimensions that is invariant under all local Pauli operations, the cost of the measurement is exactly equal to the average entanglement of the states associated with the outcomes.
description: 14 pages; new result in v4: cost of an arbitrary measurement invariant under local Pauli operations
Sensing In/Security: An Introduction. In: Klimburg-Witjes-Witjes, N., Poechhacker, N. & Bowker, G.C.(eds): Sensing In/Security: Sensors as Transnational Security Infrastructures. Mattering Press, Manchester.
Creators: name: Klimburg-Witjes, Nina
name: Poechhacker, Nikolaus
name: Bowker, Geoffrey C.
Publisher: name: Zenodo
Year: 2020
Subjects: Sensors, Security, Infrastructure, Sensing, Science and Technology Studies, Security Studies, Smart Cities, Drones

description: Sensing In/Security is a book project that investigates how sensors and sensing practices enact regimes of security and insecurity. It extends long standing concerns with infrastructuring and emergent modes of surveillance and securitization by investigating how digitally networked sensors shape practices of securitization. Contributions in this volume engage with the ways in which sensing devices gain political and epistemic relevance in various forms of security, from border security and migration control to drone regulation, epidemiological tracking, aerial surveillance and hacking practices. Using infrastructure and infrastructuring as a conceptual lens, these studies explore the conditions of possibility of sensing threats and in/security, rendering multiple worlds tangible and (sometimes even more importantly) intangible. Instead of solely focusing on the specific sensory devices and their consequences, this collection engages with the emergence of sensor infrastructures and networks and the shaping of such ‘macro entities’ as international organizations, states and the European Union.
description: Full book (open access) will be published by Mattering Press (2021)
First estimations of Gravity Wave Potential Energy in the Martian thermosphere: An analysis using MAVEN NGIMS data
Creators: name: Manju, G
name: N, Mridula
Publisher: name: arXiv
Year: 2021
Subjects: subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: First estimations of Gravity Wave Potential Energy (GWPE) for the Martian thermosphere are reported herein using the height profile of CO2 density derived temperature fluctuations for different Martian seasons during the 33rd Martian year. Explicit diurnal evolution of GWPE (for 52o to 73o latitude bin) with a post sunset maximum is delineated for summer. The higher values of GWPE are observed during morning, compared to post mid-night (35 o to 55 o latitude bin) for summer. As the latitude increases from 16 o to 45 o, GWPE (1-4 LT bin) is found to be nearly doubled for summer. Further, GWPE estimates in autumn are 6 times higher during night compared to day (-45 o to -72 o latitude bin) and daytime ( -53 o to -72 o latitude bin) GWPE is much lower in autumn compared to spring for all longitudes. Overall, from the available data autumn (with respect to northern hemisphere) daytime periods appear better suited for aero-braking operations of Martian landing missions.
description: 15 pages
Additional file 1 of Implementation and performance of haemovigilance systems in 10 sub-saharan African countries is sub-optimal
Creators: name: Samukange, Washington T.
name: Kluempers, Verena
name: Porwal, Manvi
name: Mudyiwenyama, Linda
name: Mutoti, Khamusi
name: Aineplan, Noel
name: Gardarsdottir, Helga
name: Mantel-Teeuwisse, Aukje K.
name: Nuebling, C. Micha
Publisher: name: figshare
Year: 2021
Subjects: subject: Law
subject: FOS: Law

description: Additional file 1
Harmonically confined long-ranged interacting gas in the presence of a hard wall
Creators: name: Kethepalli, Jitendra
name: Kulkarni, Manas
name: Kundu, Anupam
name: Majumdar, Satya N.
name: Mukamel, David
name: Schehr, Gregory
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: Probability (math.PR)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In this paper, we compute exactly the average density of a harmonically confined Riesz gas of $N$ particles for large $N$ in the presence of a hard wall. In this Riesz gas, the particles repel each other via a pairwise interaction that behaves as $|x_i - x_j|^{-k}$ for $k>-2$, with $x_i$ denoting the position of the $i^{\rm th}$ particle. This density can be classified into three different regimes of $k$. For $k \geq 1$, where the interactions are effectively short-ranged, the appropriately scaled density has a finite support over $[-l_k(w),w]$ where $w$ is the scaled position of the wall. While the density vanishes at the left edge of the support, it approaches a nonzero constant at the right edge $w$. For $-1
description: 33 pages, 14 figures
Viscoelastic flow past an infinite plate with suction and constant heat flux
Creators: name: Sanyal, Abhik Kumar
name: Ray, D.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: While studying the viscoelastic flow past an infinite plate with suction and constant heat flux between fluid and plate, Raptis and Tziyanidis gave the solution of a pair of equations for velocity and temperature as functions of distance. They then gave some approximate solutions. This letter shows that the approximations are not justified and presents an exact analytical study.
description: 5 pages, 0 figures
Additional file 1 of Development and selective grain make plasticity 'take the lead' in adaptive evolution
Creators: name: Brun-Usan, Miguel
name: Rago, Alfredo
name: Thies, Christoph
name: Uller, Tobias
name: Watson, Richard A.
Publisher: name: figshare
Year: 2021
Subjects: subject: Genetics
subject: FOS: Biological sciences

description: Additional file 1. Supplementary figures.
Molecules with ALMA at Planet-forming Scales (MAPS). IX. Distribution and Properties of the Large Organic Molecules HC$_3$N, CH$_3$CN, and $c$-C$_3$H$_2$
Creators: name: Ilee, John D.
name: Walsh, Catherine
name: Booth, Alice S.
name: Aikawa, Yuri
name: Andrews, Sean M.
name: Bae, Jaehan
name: Bergin, Edwin A.
name: Bergner, Jennifer B.
name: Bosman, Arthur D.
name: Cataldi, Gianni
name: Cleeves, L. Ilsedore
name: Czekala, Ian
name: Guzmán, Viviana V.
name: Huang, Jane
name: Law, Charles J.
name: Gal, Romane Le
name: Loomis, Ryan A.
name: Ménard, François
name: Nomura, Hideko
name: Öberg, Karin I
name: Qi, Chunhua
name: Schwarz, Kamber R.
name: Teague, Richard
name: Tsukagoshi, Takashi
name: Wilner, David J.
name: Yamato, Yoshihide
name: Zhang, Ke
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The precursors to larger, biologically-relevant molecules are detected throughout interstellar space, but determining the presence and properties of these molecules during planet formation requires observations of protoplanetary disks at high angular resolution and sensitivity. Here we present 0.3" observations of HC$_3$N, CH$_3$CN, and $c$-C$_3$H$_2$ in five protoplanetary disks observed as part of the Molecules with ALMA at Planet-forming Scales (MAPS) Large Program. We robustly detect all molecules in four of the disks (GM Aur, AS 209, HD 163296 and MWC 480) with tentative detections of $c$-C$_3$H$_2$ and CH$_3$CN in IM Lup. We observe a range of morphologies -- central peaks, single or double rings -- with no clear correlation in morphology between molecule nor disk. Emission is generally compact and on scales comparable with the millimetre dust continuum. We perform both disk-integrated and radially-resolved rotational diagram analysis to derive column densities and rotational temperatures. The latter reveals 5-10 times more column density in the inner 50-100 au of the disks when compared with the disk-integrated analysis. We demonstrate that CH$_3$CN originates from lower relative heights in the disks when compared with HC$_3$N, in some cases directly tracing the disk midplane. Finally, we find good agreement between the ratio of small to large nitriles in the outer disks and comets. Our results indicate that the protoplanetary disks studied here are host to significant reservoirs of large organic molecules, and that this planet- and comet-building material can be chemically similar to that in our own Solar System. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement Series.
description: 24 pages, 11 figures, 5 tables. Accepted for publication in ApJSS. Updated to cross-reference other MAPS publications
HAWK: Rapid Android Malware Detection through Heterogeneous Graph Attention Networks
Creators: name: Hei, Yiming
name: Yang, Renyu
name: Peng, Hao
name: Wang, Lihong
name: Xu, Xiaolin
name: Liu, Jianwei
name: Liu, Hong
name: Xu, Jie
name: Sun, Lichao
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Android is undergoing unprecedented malicious threats daily, but the existing methods for malware detection often fail to cope with evolving camouflage in malware. To address this issue, we present HAWK, a new malware detection framework for evolutionary Android applications. We model Android entities and behavioural relationships as a heterogeneous information network (HIN), exploiting its rich semantic metastructures for specifying implicit higher-order relationships. An incremental learning model is created to handle the applications that manifest dynamically, without the need for re-constructing the whole HIN and the subsequent embedding model. The model can pinpoint rapidly the proximity between a new application and existing in-sample applications and aggregate their numerical embeddings under various semantics. Our experiments examine more than 80,860 malicious and 100,375 benign applications developed over a period of seven years, showing that HAWK achieves the highest detection accuracy against baselines and takes only 3.5ms on average to detect an out-of-sample application, with the accelerated training time of 50x faster than the existing approach.
description: The work has been accepted by TNNLS
SearchGCN: Powering Embedding Retrieval by Graph Convolution Networks for E-Commerce Search
Creators: name: Xia, Xinlin
name: Wang, Shang
name: Zhang, Han
name: Wang, Songlin
name: Xu, Sulong
name: Xiao, Yun
name: Long, Bo
name: Yang, Wen-Yun
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences
subject: H.3.3

description: Graph convolution networks (GCN), which recently becomes new state-of-the-art method for graph node classification, recommendation and other applications, has not been successfully applied to industrial-scale search engine yet. In this proposal, we introduce our approach, namely SearchGCN, for embedding-based candidate retrieval in one of the largest e-commerce search engine in the world. Empirical studies demonstrate that SearchGCN learns better embedding representations than existing methods, especially for long tail queries and items. Thus, SearchGCN has been deployed into JD.com's search production since July 2020.
description: 2 pages, 1 figure; accepted by SIGIR2021 industry track
Ab initio studies of structures and properties of small potassium clusters
Creators: name: Banerjee, Arup
name: Ghanty, Tapan K.
name: Chakrabarti, Aparna
Publisher: name: arXiv
Year: 2008
Subjects: subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: We have studied the structure and properties of potassium clusters containing even number of atoms ranging from 2 to 20 at the ab initio level. The geometry optimization calculations are performed using all-electron density functional theory with gradient corrected exchange-correlation functional. Using these optimized geometries we investigate the evolution of binding energy, ionization potential, and static polarizability with the increasing size of the clusters. The polarizabilities are calculated by employing Moller-Plesset perturbation theory and time dependent density functional theory. The polarizabilities of dimer and tetramer are also calculated by employing large basis set coupled cluster theory with single and double excitations and perturbative triple excitations. The time dependent density functional theory calculations of polarizabilities are carried out with two different exchange-correlation potentials: (i) an asymptotically correct model potential and (ii) within the local density approximation. A systematic comparison with the other available theoretical and experimental data for various properties of small potassium clusters mentioned above has been performed. These comparisons reveal that both the binding energy and the ionization potential obtained with gradient corrected potential match quite well with the already published data. Similarly, the polarizabilities obtained with Moller-Plesset perturbation theory and with model potential are quite close to each other and also close to experimental data.
description: 33 pages including 10 figures
The oriented swap process
Creators: name: Angel, Omer
name: Holroyd, Alexander
name: Romik, Dan
Publisher: name: arXiv
Year: 2008
Subjects: subject: Probability (math.PR)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 82C22, 60K35, 60C05 (Primary)

description: Particles labelled $1,...,n$ are initially arranged in increasing order. Subsequently, each pair of neighboring particles that is currently in increasing order swaps according to a Poisson process of rate 1. We analyze the asymptotic behavior of this process as $n\to\infty$. We prove that the space--time trajectories of individual particles converge (when suitably scaled) to a certain family of random curves with two points of non-differentiability, and that the permutation matrix at a given time converges to a certain deterministic measure with absolutely continuous and singular parts. The absorbing state (where all particles are in decreasing order) is reached at time $(2+o(1))n$. The finishing times of individual particles converge to deterministic limits, with fluctuations asymptotically governed by the Tracy--Widom distribution.
description: Published in at http://dx.doi.org/10.1214/09-AOP456 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org)
A Scalable Correlator Architecture Based on Modular FPGA Hardware, Reuseable Gateware, and Data Packetization
Creators: name: Parsons, Aaron
name: Backer, Donald
name: Chen, Henry
name: Droz, Pierre
name: Filiba, Terry
name: Manley, Jason
name: MacMahon, David
name: McMahon, Peter
name: Parsa, Arash
name: Siemion, Andrew
name: Werthimer, Dan
name: Wright, Melvyn
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: A new generation of radio telescopes is achieving unprecedented levels of sensitivity and resolution, as well as increased agility and field-of-view, by employing high-performance digital signal processing hardware to phase and correlate large numbers of antennas. The computational demands of these imaging systems scale in proportion to BMN^2, where B is the signal bandwidth, M is the number of independent beams, and N is the number of antennas. The specifications of many new arrays lead to demands in excess of tens of PetaOps per second. To meet this challenge, we have developed a general purpose correlator architecture using standard 10-Gbit Ethernet switches to pass data between flexible hardware modules containing Field Programmable Gate Array (FPGA) chips. These chips are programmed using open-source signal processing libraries we have developed to be flexible, scalable, and chip-independent. This work reduces the time and cost of implementing a wide range of signal processing systems, with correlators foremost among them,and facilitates upgrading to new generations of processing technology. We present several correlator deployments, including a 16-antenna, 200-MHz bandwidth, 4-bit, full Stokes parameter application deployed on the Precision Array for Probing the Epoch of Reionization.
description: Accepted to Publications of the Astronomy Society of the Pacific. 31 pages. v2: corrected typo, v3: corrected Fig. 13
Search for long-lived particles decaying into electron or photon pairs with the D0 detector
Creators: name: D0 Collaboration
name: Abazov, V.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In this Letter we report on a search for long-lived particles that decay into final states with two electrons or photons. Such long-lived particles arise in a variety of theoretical models, like hidden valleys and supersymmetry with gauge-mediated breaking. By precisely reconstructing the direction of the electromagnetic shower we are able to probe much longer lifetimes than previously explored. We see no evidence of the existence of such long-lived particles and interpret this search as a quasi model-independent limit on their production cross section, as well as a limit on a long-lived fourth generation quark.
description: submitted to PRL
Partitions of trees and ACA'
Creators: name: Anderson, Bernard A.
name: Hirst, Jeffry L.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03D99

description: We show that a version of Ramsey's theorem for trees for arbitrary exponents is equivalent to the subsystem ACA' of reverse mathematics.
description: Final version for publication. Very minor changes. 5 pages
Zero-point vacancies in quantum solids
Creators: name: Rossi, M.
name: Vitali, E.
name: Galli, D. E.
name: Reatto, L.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: A Jastrow wave function (JWF) and a shadow wave function (SWF) describe a quantum solid with Bose--Einstein condensate; i.e. a supersolid. It is known that both JWF and SWF describe a quantum solid with also a finite equilibrium concentration of vacancies x_v. We outline a route for estimating x_v by exploiting the existing formal equivalence between the absolute square of the ground state wave function and the Boltzmann weight of a classical solid. We compute x_v for the quantum solids described by JWF and SWF employing very accurate numerical techniques. For JWF we find a very small value for the zero point vacancy concentration, x_v=(1.4\pm0.1) x 10^-6. For SWF, which presently gives the best variational description of solid 4He, we find the significantly larger value x_v=(1.4\pm0.1) x 10^-3 at a density close to melting. We also study two and three vacancies. We find that there is a strong short range attraction but the vacancies do not form a bound state.
description: 19 pages, submitted to J. Low Temp. Phys
Essays on geography and diseases
Creators: name: Esposito, Elena <1983>
Publisher: name: Alma Mater Studiorum - Università di Bologna
Year: 2014
Subjects: SECS-P/01 Economia politica

description: This dissertation explores how diseases contributed to shape historical institutions and how health and diseases are still affecting modern comparative development. The overarching goal of this investigation is to identify the channels linking geographic suitability to diseases and the emergence of historical and modern insitutions, while tackling the endogenenity problems that traditionally undermine this literature. I attempt to do so by taking advantage of the vast amount of newly available historical data and of the richness of data accessible through the geographic information system (GIS). 

The first chapter of my thesis, 'Side Effects of Immunities: The African Slave Trade', proposes and test a novel explanation for the origins of slavery in the tropical regions of the Americas. I argue that Africans were especially attractive for employment in tropical areas because they were immune to many of the diseases that were ravaging those regions. In particular, Africans' resistance to malaria increased the profitability of slaves coming from the most malarial parts of Africa.  In the second chapter of my thesis, 'Caste Systems and Technology in Pre-Modern Societies', I advance and test the hypothesis that caste systems, generally viewed as a hindrance to social mobility and development, had been comparatively advantageous at an early stage of economic development. In the third chapter, 'Malaria as Determinant of Modern Ethnolinguistic Diversity', I conjecture that in highly malarious areas the necessity to adapt and develop immunities specific to the local disease environment historically reduced mobility and increased isolation, thus leading to the formation of a higher number of different ethnolinguistic groups. In the final chapter, 'Malaria Risk and Civil Violence: A Disaggregated Analysis for Africa', I explore the relationship between malaria and violent conflicts. Using georeferenced data for Africa, the article shows that violent events are more frequent in areas where malaria risk is higher.
Gaussian Moments as Physically Inspired Molecular Descriptors for Accurate and Scalable Machine Learning Potentials
Creators: name: Zaverkin, Viktor
name: Kästner, Johannes
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Machine Learning (stat.ML)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Machine learning techniques allow a direct mapping of atomic positions and nuclear charges to the potential energy surface with almost ab-initio accuracy and the computational efficiency of empirical potentials. In this work we propose a machine learning method for constructing high-dimensional potential energy surfaces based on feed-forward neural networks. As input to the neural network we propose an extendable invariant local molecular descriptor constructed from geometric moments. Their formulation via pairwise distance vectors and tensor contractions allows a very efficient implementation on graphical processing units (GPUs). The atomic species is encoded in the molecular descriptor, which allows the restriction to one neural network for the training of all atomic species in the data set. We demonstrate that the accuracy of the developed approach in representing both chemical and configurational spaces is comparable to the one of several established machine learning models. Due to its high accuracy and efficiency, the proposed machine-learned potentials can be used for any further tasks, for example the optimization of molecular geometries, the calculation of rate constants or molecular dynamics.
Industrial education in the elementary school curriculum
Creators: name: Hickling, Kenneth Joseph
Publisher: name: University of British Columbia
Year: 2010

description: The main purpose of this study was the design of a curriculum which placed an emphasis on problem solving through the practical approach of woodworking. In more philosophical terms, it can be described as an attempt to unite thinking with doing. In order to accomplish this aim a necessary part of the study became the examination of the curriculum development process in theoretical terms, followed by the implementation of this process in the design of the proposed curriculum and finally the evaluation of the proposed curriculum in formative terms. In reviewing the literature support was found for a structured or organised framework for curriculum development. This concept of curriculum development was adapted for this study. Problem solving was given a major emphasis in the proposed curriculum, with skill development considered important, though secondary to problem solving. Creativity and design were regarded as contributing elements to the problem solving component, and projects were planned in such a way that the child would be given the opportunity for creative input and involved in the design of the project; thus problem solving became an integral part of the project. For the purpose of formative evaluation, projects from the proposed curriculum and a 1960 Grade 7 Woodworking program, were judged in respect to their problem solving and skill development components. The results of the evaluation clearly illustrated the difference in emphasis of the two programs. The 1960 program scored highly in skill development and received a low score for problem solving from independent judges. The proposed curriculum was given an above average score for skill development and a high score for problem solving. In conclusion it was noted that: (1) Experience played a major part in the classroom teacher's approach to curriculum development, and that this would have important implications with regard to beginning teachers. (2) The project evaluation format, with some refinements, could be utilized in other areas of Industrial Education. (3) The proposed curriculum with its emphasis on "thinking" could be of benefit in programs for gifted children. It was also recommended that the proposed curriculum be implemented in an elementary school in order that the process of summative evaluation may be accomplished.
Modeling the kinetic behavior of the Li-RHC system for energy-hydrogen storage : ( I ) absorption
Creators: name: Neves, A. M.
name: Puszkiel, J.
name: Capurso, G.
name: von Colbe, J. M. Bellosta
name: Milanese, C.
name: Dornheim, M.
name: Klassen, T.
name: Jepsen, J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The Lithium-Boron Reactive Hydride Composite System (Li-RHC) (2 LiH + MgB$_{2}$ / 2 LiBH$_{4}$ + MgH$_{2}$) is a high-temperature hydrogen storage material suitable for energy storage applications. Herein, a comprehensive gas-solid kinetic model for hydrogenation is developed. Based on thermodynamic measurements under absorption conditions, the system's enthalpy $Δ$H and entropy $Δ$S are determined to amount to -34 $\pm$ 2 kJ $\cdot$ mol H$_{2}^{-1}$ and -70 $\pm$ 3 J $\cdot$ K$^{-1}$ $\cdot$ mol H$_{2}^{-1}$, respectively. Based on the thermodynamic behavior assessment, the kinetic measurements' conditions are set in the range between 325 °C and 412 °C, as well as between 15 bar and 50 bar. The kinetic analysis shows that the hydrogenation rate-limiting-step is related to a one-dimensional interface-controlled reaction with a driving-force-corrected apparent activation energy of 146 $\pm$ 3 kJ $\cdot$ mol H$_{2}^{-1}$. Applying the kinetic model, the dependence of the reaction rate constant as a function of pressure and temperature is calculated, allowing the design of optimized hydrogen/energy storage vessels via finite element method (FEM) simulations.
description: Accepted Manuscript Version (with Supplementary Material) of the Preprint submitted to the International Journal of Hydrogen Energy on April 12th 2021 and Accepted on June 28th 2021
Dark Matter signals from Draco and Willman 1: Prospects for MAGIC II and CTA
Creators: name: Bringmann, Torsten
name: Doro, Michele
name: Fornasa, Mattia
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The next generation of ground-based Imaging Air Cherenkov Telescopes (IACTs) will play an important role in indirect dark matter searches. In this article, we consider two particularly promising candidate sources for dark matter annihilation signals, the nearby dwarf galaxies Draco and Willman 1, and study the prospects of detecting such a signal for the soon-operating MAGIC II telescope system as well as for the planned installation of CTA, taking special care of describing the experimental features that affect the detectional prospects. For the first time in such a study, we fully take into account the effect of internal bremsstrahlung, which has recently been shown to considerably enhance, in some cases, the gamma-ray flux at the high energies where Atmospheric Cherenkov Telescopes operate, thus leading to significantly harder annihilation spectra than traditionally considered. While the detection of the spectral features introduced by internal bremsstrahlung would constitute a smoking gun signature for dark matter annihilation, we find that for most models the overall flux still remains at a level that will be challenging to detect unless one adopts rather (though by no means overly) optimistic astrophysical assumptions about the distribution of dark matter in the dwarfs.
description: 10 pages, 4 figures, minor changes, matches the published version (JCAP)
Self-masking of spontaneous symmetry breaking in layer materials
Creators: name: Yamase, Hiroyuki
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We study d-wave Fermi surface deformations (dFSD), the so-called Pomeranchuk instability, on bilayer and infinite-layer square lattices. Since the order parameter of the dFSD has Ising symmetry, there are two stacking patterns along the c axis: (+,+) and (+,-). We find that, as long as the c axis dispersion is finite at the saddle points of the in-plane band dispersion, the (+,-) stacking is usually favored independently on the details of interlayer coupling, yielding no macroscopic anisotropy. The dFSD provides unique spontaneous symmetry breaking that is self-masked in layer materials.
description: 5 pages, 3 figures, published version
Radio Interferometric Observations of the Sun Using Commercial Dish TV Antennas
Creators: name: Gireesh, G. V. S.
name: Kathiravan, C.
name: Barve, Indrajit V.
name: Ramesh, R.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The radio astronomy group in the Indian Institute of Astrophysics (IIA) has been carrying out routine observations of radio emission from the solar corona at low frequencies (${\approx}$40-440MHz) at the Gauribidanur observatory, about 100km north of Bangalore. Since IIA has been performing regular observations of the solar photosphere and chromosphere using different optical telescopes in its Kodaikanal Solar Observatory (KSO) also, the possibilities of obtaining two-dimensional radio images of the solar chromosphere using low-cost instrumentation to supplement the optical observations are being explored. As a part of the exercise, recently the group had developed prototype instrumentation for interferometric observations of radio emission from the solar chromosphere at high frequencies (${\approx}$11.2GHz) using two commercial dish TV antennas. The hardware set-up and initial observations are presented.
description: Published in Solar Physics, 11 pages, 6 figures