cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
High order well-balanced asymptotic preserving finite difference WENO schemes for the shallow water equations in all Froude numbers
Creators: name: Huang, Guanlan
name: Xing, Yulong
name: Xiong, Tao
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: In this paper, high order semi-implicit well-balanced and asymptotic preserving finite difference WENO schemes are proposed for the shallow water equations with a non-flat bottom topography. We consider the Froude number ranging from O(1) to 0, which in the zero Froude limit becomes the "lake equations" for balanced flow without gravity waves. We apply a well-balanced finite difference WENO reconstruction, coupled with a stiffly accurate implicit-explicit (IMEX) Runge-Kutta time discretization. The resulting semi-implicit scheme can be shown to be well-balanced, asymptotic preserving (AP) and asymptotically accurate (AA) at the same time. Both one- and two-dimensional numerical results are provided to demonstrate the high order accuracy, AP property and good performance of the proposed methods in capturing small perturbations of steady state solutions.
Numerical simulation of hydraulic fracturing: a hybrid FEM based algorithm
Creators: name: Wrobel, Michal
name: Papanastasiou, Panos
name: Peck, Daniel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mathematical Physics (math-ph)
subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: In this paper a problem of numerical simulation of hydraulic fractures is considered. An efficient algorithm of solution is proposed for the plain strain model of hydraulic fracturing. The algorithm utilizes a FEM based subroutine to compute deformation of the fractured material. The flow of generalized Newtonian fluid in the fracture is modelled in the framework of lubrication theory. In this way, the architecture of the computational scheme is relatively simple and enables one to deal with advanced cases of the fractured material properties and configurations as well as various rheological models of fluid. In particular, the problems of poroelasticity, plasticity and spatially varying properties of the fractured material can be analyzed. The accuracy and efficiency of the proposed algorithm are verified against analytical benchmark solutions. The algorithm capabilities are demonstrated using the example of the hydraulic fracture propagating in complex geological settings.
Deep Learning for Real-Time Aerodynamic Evaluations of Arbitrary Vehicle Shapes
Creators: name: Jacob, Sam Jacob
name: Mrosek, Markus
name: Othmer, Carsten
name: Köstler, Harald
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: FOS: Computer and information sciences

description: The aerodynamic optimization process of cars requires multiple iterations between aerodynamicists and stylists. Response Surface Modeling and Reduced-Order Modeling are commonly used to eliminate the overhead due to Computational Fluid Dynamics, leading to faster iterations. However, a primary drawback of these models is that they can work only on the parametrized geometric features they were trained with. This study evaluates if deep learning models can predict the drag coefficient for an arbitrary input geometry without explicit parameterization. We use two similar data sets based on the publicly available DrivAer geometry for training. We use a modified U-Net architecture that uses Signed Distance Fields to represent the input geometries. Our models outperform the existing models by at least 11% in prediction accuracy for the drag coefficient. We achieved this improvement by combining multiple data sets that were created using different parameterizations, which is not possible with the methods currently used. We have also shown that it is possible to predict velocity fields and drag coefficient concurrently and that simple data augmentation methods can improve the results. In addition, we have performed an occlusion sensitivity study on our models to understand what information is used to make predictions. From the occlusion sensitivity study, we showed that the models were able to identify the geometric features and have discovered that the model has learned to exploit the global information present in the SDF. In contrast to the currently operational method, where design changes are restricted to the initially defined parameters, this study brings surrogate models one step closer to the long-term goal of having a model that can be used for approximate aerodynamic evaluation of unseen, arbitrary vehicle shapes, thereby providing complete design freedom to the vehicle stylists.
Thermal Hall response: violation of gravitational analogues and Einstein relations
Creators: name: Park, Jinhong
name: Golan, Omri
name: Vinkler-Aviv, Yuval
name: Rosch, Achim
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The response of solids to temperature gradients is often described in terms of a gravitational analogue: the effect of a space-dependent temperature is modeled using a space dependent metric. We investigate the validity of this approach in describing the bulk response of quantum Hall states and other gapped chiral topological states. To this end, we consider the prototypical Haldane model in two different cases of (i) a space-dependent electrostatic potential and gravitational potential and (ii) a space-dependent temperature and chemical potential imprinted by a weak coupling to non-interacting electron baths and phonons. We find that the thermal analogue is \textit{invalid}; while a space dependent gravitational potential induces transverse energy currents proportional to the third derivative of the gravitational potential, the response to an analogous temperature profile vanishes in limit of weak coupling to the thermal bath. Similarly, the Einstein relation, the analogy between the electrostatic potential and the internal chemical potential, is not valid in such a setup.
description: In the latest version, we have added the part to include phonon baths for internal equilibration and a more realistic way to imprint a temperature profile onto the system. 17 pages (5 pages for the main text and 12 pages for the supplementary material), 8 figures (4+4)
Piecewise Interaction Picture Density Matrix Quantum Monte Carlo
Creators: name: Van Benschoten, William
name: Shepherd, James J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: The density matrix quantum Monte Carlo (DMQMC) set of methods stochastically samples the exact $N$-body density matrix for interacting electrons at finite temperature. We introduce a simple modification to the interaction picture DMQMC method (IP-DMQMC) which overcomes the limitation of only sampling one inverse temperature point at a time, instead allowing for the sampling of a temperature range within a single calculation thereby reducing the computational cost. At the target inverse temperature, instead of ending the simulation, we incorporate a change of picture away from the interaction picture. The resulting equations of motion have piecewise functions and use the interaction picture in the first phase of a simulation, followed by the application of the Bloch equation once the target inverse temperature is reached. We find that the performance of this method is similar to or better than the DMQMC and IP-DMQMC algorithms in a variety of molecular test systems.
Artifact of Gin LLM ASE extention
Creators: name: anon.
Publisher: name: Zenodo
Year: 2024

description: This is the artefact of the paper adding LLM to Gin: the extension of the original SSBSE 2023 paper with additional data.

The code, LLMs prompt and experimental infrastructure, data from the evaluation, and results are available as open source here. The code is also under the ‘llm’ branch of github.com/gintool/gin (commit fa9fc41; branched from master commit 2359f57 pending full integration with Gin).

 

We evaluated our idea on the following targets:

Project
URL
Branch

JCodec
github.com/jcodec/jcodec
master (7e52834)

JUnit4
github.com/junit-team/junit4
r4.13.2

GSON
github.com/google/gson  
gson-parent-2.10.1

commons-net
github.com/apache/commons-net
rel/commons-net-3.10.0

karate
github.com/karatelabs/karate
v1.4.1  

 

Tested on the following machines/Spec.: 17.0.9 & 3.9.6 & 0.1.27

Project, Search (LLM)  
Machine Specification
Java Version
Maven Version
Ollama Version

JCodec, RS (OpenAI, Mistral)
AMD Threadripper 3990x, 64C/128T, 128GB, Titan RTX
17.0.10
3.9.6
0.1.28 

JCodec, RS (tinydolphin)
Intel Xeon W-2245, 8C/16T, 128GB, RTX 2080 TI
17.0.8
3.9.6
0.1.27

JCodec, LS (*)
Intel Xeon 2620v3, 12C/24T, 32GB, Titan X
17.0.9
3.9.0
0.1.24

GSON, RS (OpenAI, Mistral)
AMD Threadripper 3990x, 64C/128T, 128GB, Titan RTX
17.0.10
3.9.6
0.1.28 

GSON, RS (tinydolphin)
Intel Xeon W-2245, 8C/16T, 128GB, RTX 2080 TI  
17.0.8
3.9.6
0.1.27

GSON, LS (*)  
Intel Xeon W-2245, 8C/16T, 128GB, RTX 2080 TI 
17.0.8
3.9.6
0.1.27

JUnit4, RS & LS (*)  
Intel Xeon 2620v3, 12C/24T, 32GB, Titan X  
17.0.9
3.9.0
0.1.24

commons-net, RS & LS (*)
Intel Xeon 2620v4, 16C/32T, 32GB    
17.0.9
3.9.6
0.1.27

karate, RS & LS (*)
Intel Xeon 2620v3, 12C/24T, 32GB, Titan X
17.0.9
3.9.0
0.1.24

 

In the table: we specified each machine's specifications for each experiment. The target project describes an experiment, the search type (local search (LS) or random search (RS)) and the LLM model used. An asterisk means the specification refers to all LLM models used.

 

We employed Ollama in its CPU mode to prompt from TinyDolphin (0f9dd11f824c, 637MB) and Mistral (61e88e884507, 4.1GB). We used ChatGPT 3.5.
Superfluid Effective Field Theory for Dark Matter Direct Detection
Creators: name: Matchev, Konstantin T.
name: Smolinsky, Jordan
name: Xue, Wei
name: You, Yining
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Superconductivity (cond-mat.supr-con)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We develop an effective field theory (EFT) framework for superfluid ${}^4$He to model the interactions among quasiparticles, helium atoms and probe particles. Our effective field theory approach brings together symmetry arguments and power-counting and matches to classical fluid dynamics. We then present the decay and scattering rates for the relevant processes involving quasiparticles and helium atoms. The presented EFT framework and results can be used to understand the dynamics of thermalization in the superfluid, and can be further applied to sub-GeV dark matter direct detection with superfluid ${}^4$He.
description: 29 pages, 9 figures, minor changes, references added
Fermions on a torus knot
Creators: name: Filho, A. A. Araújo
name: Reis, J. A. A. S.
name: Ghosh, Subir
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this work, we investigate the effects of a nontrivial topology (and geometry) of a system considering \textit{interacting} and \textit{noninteracting} particle modes, which are restricted to follow a closed path over the torus surface. In order to present a prominent thermodynamical investigation of this system configuration, we carry out a detailed analysis using statistical mechanics within the grand canonical ensemble approach to deal with \textit{noninteracting} fermions. In an analytical manner, we study the following thermodynamic functions in such context: the Helmholtz free energy, the mean energy, the magnetization and the susceptibility. Further, we take into account the behavior of Fermi energy of the thermodynamic system. Finally, we briefly outline how to proceed in case of \textit{interacting} fermions.
description: 25 pages, and 13 figures
Deriving dilaton potential in improved holographic QCD from meson spectrum
Creators: name: Hashimoto, Koji
name: Ohashi, Keisuke
name: Sumimoto, Takayuki
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We derive an explicit form of the dilaton potential in improved holographic QCD (IHQCD) from the experimental data of the $ρ$ meson spectrum. For this purpose we make use of the emergent bulk geometry obtained by deep learning from the hadronic data in arXiv:2005.02636. Requiring that the geometry is a solution of an IHQCD derives the corresponding dilaton potential backwards. This determines the bulk action in a data-driven way, which enables us at the same time to ensure that the deep learning proposal is a consistent gravity. Furthermore, we find that the resulting potential satisfies the requirements normally imposed in IHQCD, and that the holographic Wilson loop for the derived model exhibits quark confinement.
description: 7pages, 5figures. v2: footnote 6 added
Quantum Oscillations between weakly coupled Bose-Einstein Condensates: Evolution in a Non-degenerate Double Well
Creators: name: Andersen, John D.
name: Raghavan, Srikanth
name: Kenkre, V. M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We discuss coherent atomic oscillations between two weakly coupled Bose-Einstein condensates that are energetically different. The weak link is notionally provided by a laser barrier in a (possibly asymmetric) multi-well trap or by Raman coupling between condensates in different hyperfine levels. The resultant boson Josephson junction dynamics is described by a double-well nonlinear Gross-Pitaevskii equation. On the basis of a new set of Jacobian elliptic function solutions, we describe the period of the oscillations as well as associated quantities and predict novel observable consequences of the interplay of the energy difference and initial phase difference between the two condensate populations.
description: 18 pages, 5 figures
Logarithmic, noise-induced dynamics in the Anderson insulator
Creators: name: Lezama, Talía L. M.
name: Lev, Yevgeny Bar
Publisher: name: arXiv
Year: 2021
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We study the dynamical behavior of the Anderson insulator in the presence of a local noise. We show that the noise induces logarithmically slow energy and entanglement growth, until the system reaches an infinite-temperature state, where both quantities saturate to extensive values. The saturation value of the entanglement entropy approaches the average entanglement entropy over all possible product states. At infinite temperature, we find that a density excitation spreads logarithmically with time, without any signs of asymptotic diffusive behavior. In addition, we provide a theoretical picture which qualitatively reproduces the phenomenology of particle transport.
description: 7 pages, 4 figures; added references and discussion of the entanglement entropy asymptotic value
Dynamics of flowing 2D skyrmions
Creators: name: Coelho, Rodrigo C. V.
name: Tasinkevych, Mykola
name: da Gama, Margarida M. Telo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Computational Physics (physics.comp-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We investigate, numerically, the effects of externally imposed material flows on the structure and temporal evolution of liquid crystal skyrmions. The dynamics of a 2D system of skyrmions is modeled using the Ericksen-Leslie theory, which is based on two coupled equations, one for material flow and the other for the director field. As the time scales of the velocity and director fields differ by several orders of magnitude for realistic values of the system parameters, we have simplified the calculations by assuming that the velocity relaxes instantaneously when compared to the relaxation of the director field. Thus, we have used a finite-differences method known as artificial compressibility with adaptive time step to solve the velocity field and a fourth-order Runge-Kutta method for the director field. We characterized the skyrmion shape or configuration as a function of the time and the average velocity of the flow field. We found that for velocities above a certain threshold, the skyrmions stretch in the direction perpendicular to the flow, by contrast to the regime of weak flows where the skyrmions stretch along the streamlines of the flow field. These two regimes are separated by an abrupt (first-order) dynamical transition, which is robust with respect to e.g., the liquid crystal elastic anisotropy. Additionally, we have found how the presence of a second skyrmion affects the evolution of the shape of the skyrmions, by comparing the evolution of pairs of skyrmions to the evolution of a single-skyrmion.
A puzzle solved after two decades: SN 2002gh among the brightest of superluminous supernovae
Creators: name: Cartier, Régis
name: Hamuy, Mario
name: Contreras, Carlos
name: Anderson, Joseph P.
name: Phillips, Mark M.
name: Morrell, Nidia
name: Stritzinger, Maximilian D.
name: Hueichapan, Emilio D.
name: Clocchiatti, Alejandro
name: Roth, Miguel
name: Thomas-Osip, Joanna
name: González, Luis E.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present optical photometry and spectroscopy of the superluminous SN 2002gh from maximum light to $+204$ days, obtained as part of the Carnegie Type II Supernova (CATS) project. SN 2002gh is among the most luminous discovered supernovae ever, yet it remained unnoticed for nearly two decades. Using Dark Energy Camera archival images we identify the potential SN host galaxy as a faint dwarf galaxy, presumably having low metallicity, and in an apparent merging process with other nearby dwarf galaxies. We show that SN 2002gh is among the brightest hydrogen-poor SLSNe with $M_{V} = -22.40 \pm 0.02$, with an estimated peak bolometric luminosity of $2.6 \pm 0.1 \times 10^{44}$ erg s$^{-1}$. We discount the decay of radioactive nickel as the main SN power mechanism, and assuming that the SN is powered by the spin down of a magnetar we obtain two alternative solutions. The first case, is characterized by significant magnetar power leakage, and $M_{\mathrm{ej}}$ between 0.6 and 3.2 $M_{\odot}$, $P_{\mathrm{spin}} = 3.2$ ms, and $B = 5 \times 10^{13}$ G. The second case does not require power leakage, resulting in a huge ejecta mass of about 30 $M_{\odot}$, a fast spin period of $P_{\mathrm{spin}} \sim 1$ ms, and $B\sim 1.6 \times 10^{14}$ G. We estimate a zero-age main-sequence mass between 14 and 25 $M_{\odot}$ for the first case and of about 135 $M_{\odot}$ for the second case. The latter case would place the SN progenitor among the most massive stars observed to explode as a SN.
description: 25 pages, 18 figures, accepted for publication in MNRAS
Data management planning in ELIXIR
Creators: name: Hooft, Rob
name: Jareborg, Niclas
name: Coppens, Frederik
name: Stockinger, Heinz
name: Pergl, Robert
name: Leskošek, Brane
Publisher: name: F1000Research
Year: 2016

description: The ELIXIR research infrastructure bundles not only the databases and tools of bioinformatics, but it also brings together life science data expertise. The assembled expertise can form a fantastic resource for researchers making a data management plan (DMP). Currently, this expertise is hard to discover and access. Several of the ELIXIR nodes are looking for ways to offer DMP services to their communities. The technical coordinators in these nodes are planning to build these services together with training coordinators. Current plans call for a data management planning (data stewardship planning) portal and trainings on many different data management (planning) topics.

Authors on this poster are representatives from six ELIXIR nodes that are initially participating in this work, other people from these ELIXIR nodes have contributed to the plans.
Implementation and Optimization of the PTOLEMY Transverse Drift Electromagnetic Filter
Creators: name: Apponi, A.
name: Betti, M. G.
name: Borghesi, M.
name: Boscá, A.
name: Calle, F.
name: Canci, N.
name: Cavoto, G.
name: Chang, C.
name: Chung, W.
name: Cocco, A. G.
name: Colijn, A. P.
name: D'Ambrosio, N.
name: de Groot, N.
name: Faverzani, M.
name: Ferella, A.
name: Ferri, E.
name: Ficcadenti, L.
name: Garcia-Abia, P.
name: Gomez-Tejedor, G. Garcia
name: Gariazzo, S.
name: Gatti, F.
name: Gentile, C.
name: Giachero, A.
name: Hochberg, Y.
name: Kahn, Y.
name: Kievsky, A.
name: Lisanti, M.
name: Mangano, G.
name: Marcucci, L. E.
name: Mariani, C.
name: Martínez, J.
name: Messina, M.
name: Monticone, E.
name: Nucciotti, A.
name: Orlandi, D.
name: Pandolfi, F.
name: Parlati, S.
name: Pedrós, J.
name: Heros, C. Pérez de los
name: Pisanti, O.
name: Polosa, A. D.
name: Puiu, A.
name: Rago, I.
name: Raitses, Y.
name: Rajteri, M.
name: Rossi, N.
name: Rozwadowska, K.
name: Rucandio, I.
name: Ruocco, A.
name: Santorelli, R.
name: Strid, C. F.
name: Tan, A.
name: Tully, C. G.
name: Viviani, M.
name: Zeitler, U.
name: Zhao, F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The PTOLEMY transverse drift filter is a new concept to enable precision analysis of the energy spectrum of electrons near the tritium beta-decay endpoint. This paper details the implementation and optimization methods for successful operation of the filter. We present the first demonstrator that produces the required magnetic field properties with an iron return-flux magnet. Two methods for the setting of filter electrode voltages are detailed. The challenges of low-energy electron transport in cases of low field are discussed, such as the growth of the cyclotron radius with decreasing magnetic field, which puts a ceiling on filter performance relative to fixed filter dimensions. Additionally, low pitch angle trajectories are dominated by motion parallel to the magnetic field lines and introduce non-adiabatic conditions and curvature drift. To minimize these effects and maximize electron acceptance into the filter, we present a three-potential-well design to simultaneously drain the parallel and transverse kinetic energies throughout the length of the filter. These optimizations are shown, in simulation, to achieve low-energy electron transport from a 1 T iron core (or 3 T superconducting) starting field with initial kinetic energy of 18.6 keV drained to <10 eV (<1 eV) in about 80 cm. This result for low field operation paves the way for the first demonstrator of the PTOLEMY spectrometer for measurement of electrons near the tritium endpoint to be constructed at the Gran Sasso National Laboratary (LNGS) in Italy.
description: 29 pages, 25 figures
Implementation of residual nucleus de-excitations associated with proton decays in $^{12} {\rm C}$ based on the GENIE generator and TALYS code
Creators: name: Hu, Hang
name: Guo, Wan-Lei
name: Su, Jun
name: Wang, Wei
name: Yuan, Cenxi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We implement the de-excitation processes of residual nuclei associated with proton decays in $^{12} {\rm C}$ based on the GENIE generator and TALYS code. To derive the reasonable excitation energy spectra of residual nuclei $^{11} {\rm B}$, $^{10} {\rm B}$ and $^{10} {\rm Be}$, the default GENIE nucleon decay generator is modified in terms of the Spectral Function nuclear model. Then we use the TALYS code to estimate the de-excitation processes of residual nuclei. The TALYS calculation can partly account for the experimental data.
description: 9 pages, 8 figures and 7 tables; v3: some discussions added, to appear in Physics Letters B
Ray tracing and finite element modeling of sound propagation in a compartment fire
Creators: name: Abbasi, Mustafa Z.
name: Wilson, Preston S.
name: Ezekoye, Ofodike A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: A compartment fire (a fire in a room or building) creates temperature gradients and inhomogeneous time-varying temperature, density, and flow fields. This work compared experimental measurements of the room acoustic impulse/frequency response in a room with a fire to numerically modeled responses. The fire is modeled using Fire Dynamics Simulator (FDS). Acoustic modeling was performed using the temperature field computed by FDS. COMSOL Multiphysics was used for finite element acoustic modeling and Bellhop for ray-trace acoustics modeling. The results show that the fire causes wave-fronts to arrive earlier (due to the higher sound speed) and with more variation in the delay times (due to the sound speed perturbations). The frequency response shows that the modes are shifted up in frequency and high frequency (>2500 Hz) modes are significantly attenuated. Model results are compared with data and show good agreement in observed trends.
Towards Generalization in Dialog through Inductive Biases
Creators: name: Mehri, Shikib
Publisher: name: Carnegie Mellon University
Year: 2025
Subjects: classificationCode: 4602
subject: Artificial intelligence
classificationCode: 460306
subject: Image processing

description: Generalization is imperative in dialog research. Data-driven models have been shown to be capable of performing specific tasks in constrained contexts, given ample data. However, the complexity of human communication necessitates that models of dialog be capable of generalizing beyond the limitations of any finite corpus. Models of dialog must be able to generalize to unseen and unforeseen phenomena. This thesis studies four classes of generalization: (1) generalization to new inputs, (2) generalization to new problems, (3) generalization to new outputs and (4) generalization to new dialog tasks. Inductive biases are studied in order to facilitate these four classes of generalization. An inductive bias is motivated by prior knowledge (e.g., domain knowledge, knowledge of the desired generalizations) and aims to influence the abstractions learned by a model in order to induce generalization. Four categories of inductive biases are studied: (1) through self-supervised learning, (2) inductive biases in the model architecture, (3) inductive biases in the problem formulation and (4) the task specification as an inductive bias. This thesis consists of four chapters, each corresponding to one class of inductive bias. Chapter 3 studies self-supervised learning as an inductive bias and validates the use of the self-supervised training data and the self-supervised objectives as a mechanism for facilitating generalization to new inputs, new problems and new outputs. Chapter 4 incorporates inductive biases into the model architecture thereby prescribing a specific procedure by which the model infers the output from a given input. Through inductive biases in the model architecture, models are shown to generalize to new inputs/domains and to new outputs. Chapter 5 studies inductive biases in the problem formulation, wherein a problem is reformulated to better align with the capabilities of a pre-trained model. Both dialog evaluation and slot filling are reformulated to the task of response generation, which facilitates zero-shot generalization to new inputs and new outputs. Chapter 6 explores the most challenging class of generalization in dialog: generalization to new tasks. To transfer to unseen tasks (e.g., restaurant reservations) in a zero-shot setting, the task specification is used as an inductive bias. The task specification is a minimal expression of the task-specific properties that must be learned by a data-driven model. This thesis studies several mechanisms for using the task specification as an inductive bias: as an input, during the creation of synthetic data and as part of the model architecture. Leveraging the task specification as an inductive bias results in significant performance gains in zero-shot generalization to unseen tasks.
Learning JPEG Compression Artifacts for Image Manipulation Detection and Localization
Creators: name: Kwon, Myung-Joon
name: Nam, Seung-Hun
name: Yu, In-Jae
name: Lee, Heung-Kyu
name: Kim, Changick
Publisher: name: arXiv
Year: 2021
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: Multimedia (cs.MM)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Detecting and localizing image manipulation are necessary to counter malicious use of image editing techniques. Accordingly, it is essential to distinguish between authentic and tampered regions by analyzing intrinsic statistics in an image. We focus on JPEG compression artifacts left during image acquisition and editing. We propose a convolutional neural network (CNN) that uses discrete cosine transform (DCT) coefficients, where compression artifacts remain, to localize image manipulation. Standard CNNs cannot learn the distribution of DCT coefficients because the convolution throws away the spatial coordinates, which are essential for DCT coefficients. We illustrate how to design and train a neural network that can learn the distribution of DCT coefficients. Furthermore, we introduce Compression Artifact Tracing Network (CAT-Net) that jointly uses image acquisition artifacts and compression artifacts. It significantly outperforms traditional and deep neural network-based methods in detecting and localizing tampered regions.
description: The version of record of this article, published in the International Journal of Computer Vision (IJCV), is available online at Publisher's website: https://link.springer.com/article/10.1007/s11263-022-01617-5 ; Code is available at: https://github.com/mjkwon2021/CAT-Net
Fast generation of Cat states in Kerr nonlinear resonators via optimal adiabatic control
Creators: name: Xue, Jiao-Jiao
name: Yu, Ke-Hui
name: Liu, Wen-Xiao
name: Wang, Xin
name: Li, Hong-Rong
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Macroscopic cat states have been widely studied to illustrate fundamental principles of quantum physics as well as their application in quantum information processing. In this paper, we propose a quantum speedup method for adiabatic creation of cat states in a Kerr nonlinear resonator via gradient-descent optimal adiabatic control. By simultaneously adiabatic tuning the the cavity detuning and driving field strength, the width of minimum energy gap between the target trajectory and non-adiabatic trajectory can be widen, which allows us to speed up the evolution along the adiabatic path. Compared with the previous proposal of preparing the cat state by only controlling two-photon pumping strength in a Kerr nonlinear resonator, our method can prepare the target state with much shorter time, as well as a high fidelity and a large non-classical volume. It is worth noting that the cat state prepared by our method is also robust against single-photon loss very well. Moreover, when our proposal has a large initial detuning, it will creates a large-size cat state successfully. This proposal of preparing cat states can be implemented in superconducting quantum circuits, which provides a quantum state resource for quantum information encoding and fault-tolerant quantum computing.
Distance-based online bioinformatics training in Africa: the H3ABioNet experience
Creators: name: Gurwitz, Kim
name: Aron, Shaun
name: Sumir Panji
name: Maslamoney, Suresh
name: Fernandes, Pedro
name: Judge, David P
name: Mulder, Nicola
Publisher: name: F1000Research
Year: 2016

description: Africa is not unique in its need for basic bioinformatics training for individuals from a molecular biology background. However, unique logistical challenges in Africa, most notably access to bioinformatics expertise and internet stability, must be addressed in order to meet this need on the continent. H3ABioNet (www.h3abionet.org), the Pan African Bioinformatics Network for H3Africa, has therefore developed an innovative, free Introduction to bioinformatics course taking these challenges into account. A distance-based learning model has been selected for this 3 month course (July-September 2016) to increase access to expert African and European Bioinformatics trainers covering several bioinformatics topics, including: databases and resources; genomics; Linux; sequence alignment; and phylogenetics.

Classrooms with a total of >350 participants are hosted at 20 institutions, across 11 African countries, in order to provide local administrative and academic support. Classroom selection was based on certain infrastructure criteria, including: computer resources; Internet access; and availability of local teaching assistants. Although lectures are delivered live to remote sites via an online platform, to ensure that classroom success does not rely on stable Internet, classrooms can watch pre-recorded and pre-downloaded lecture videos, as well as work through practical assignments on the lecture content, during biweekly contact sessions. Lecture recordings are available on the course website http://training.h3abionet.org/IBT_2016/. While trainers are available via video conferencing to take questions during contact sessions, online ‘question and discussion’ forums, hosted on the course management platform, are also available. This distance based model, developed for a resource limited setting, could easily be adapted to other settings.
On Larger $H_0$ Values in the CMB Dipole Direction
Creators: name: Luongo, Orlando
name: Muccino, Marco
name: Colgáin, Eoin Ó
name: Sheikh-Jabbari, M. M.
name: Yin, Lu
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: On the assumption that quasars (QSO) and gamma-ray bursts (GRB) represent \textit{standardisable candles}, we provide evidence that the Hubble constant $H_0$ adopts larger values in hemispheres aligned with the CMB dipole direction. If substantiated, this trend signals a departure from FLRW cosmology. In particular, QSOs show a definite trend, whereas our findings in GRBs are consistent with an isotropic Universe, but we show in a sample of GRBs calibrated with Type Ia supernovae (SN) that this conclusion may change as one focuses on GRBs more closely (mis)aligned with the CMB dipole direction. The statistical significance in QSOs alone is $\gtrsim 2 σ$ and when combined with similar trends in strong lensing, Type Ia SN and calibrated GRBs, this increases to $\sim 3 σ$. Our findings are consistent with reported discrepancies in the cosmic dipole and anisotropies in galaxy cluster scaling relations. The reported variations in $H_0$ across the sky suggest that Hubble tension may be a symptom of a deeper cosmological malaise.
description: v1 align with the CMB dipole at sites.google.com/apctp.org/cosmoprinciple; v2 simulations and references added, presentation improved; v3 the anisotropic Universe marches on at PRD
SNP based literature and data retrieval
Creators: name: Veldsman, Werner P.
name: Christoffels, Alan
Publisher: name: F1000Research
Year: 2016

description: This poster illustrates a software system, called SniPhunter, that combines a VCF file parsing feature with search engine functionality. The search engine focuses on returning relevant biomedical literature for query constructs that contain reference single nucleotide polymorphism identifiers (refSNPs). Keywords assigned to articles by their authors can also be used to launch queries, however, results are always within the context of refSNPs.

The need for this type of service was identified from an observation that ontological integration of search engines has not yet advanced to the state where they provide optimum results when a user is interested in retrieving academic literature relevant to a refSNP of interest. The indexed literature within the underlying database of SNiPhunter was derived from the Pubmed Central open access initiative. The database itself can be defined as a NoSQL database that relies on the NodeJS interpreter to serve data via a web application and application programming interface. Extraction of data from the Pubmed Central corpus was carried out using Python scripts.

Results to queries launched via the SNiPhunter search engine are ordered according to the amount of times a refSNP has occurred within an article, which allows the user to make a quantitative estimate as to the relevance of the article. In addition, the article's correspondence email address is included in the results to facilitate communication between scientists. Other information such as publishing dates and digital object identifiers, that are typically included in the results of established search engines, are also returned to the user.
Collection efficiency of optical photons generated from microwave excitations of a Bose-Einstein condensate
Creators: name: Kurkó, Árpád
name: Domokos, Péter
name: Petrosyan, David
name: Vukics, András
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Stimulated Raman scattering of atoms with $Λ$-configuration of levels is a promising tool for transducing microwave photons to optical photons. We consider an atomic Bose-Einstein condensate whose large phase-space density highly amplifies the coupling to the microwave field. Due momentum transfer to the condensate, stimulated photon scattering can occur outside of the phase-matched direction, which can be used to separate the converted photons from the strong Raman readout pulse. Conversely, in the phase-matched direction, superradiant scattering due to bosonic enhancement leads to increased efficiency of the microwave to optical conversion. We determine the optimal conditions for the emitted optical photons to be collected into the guided modes of optical fibers.
Using in-plane anisotropy to engineer Janus monolayers of rhenium dichalcogenides
Creators: name: Zibouche, Nourdine
name: Gunasekera, Surani M.
name: Wolverson, Daniel
name: Mucha-Kruczynski, Marcin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The new class of Janus two-dimensional (2D) transition-metal dichalcogenides with two different interfaces are currently gaining increasing attention due to their distinct properties different from the typical 2D materials. Here, we show that in-plane anisotropy of a 2D atomic crystal, like ReS$_{2}$ or ReSe$_{2}$, allows formation of a large number of inequivalent Janus monolayers. We use first-principles calculations to investigate the structural stability of 29 distinct ReX$_{2-x}$Y$_{x}$ ($\mathrm{X,Y \in \{S,Se\}}$) structures, which can be obtained by selective exchange of exposed chalcogens in a ReX$_{2}$ monolayer. We also examine the electronic properties and work function of the most stable Janus monolayers and show that the large number of inequivalent structures provides a way to engineer spin-orbit splitting of the electronic bands. We find that the breaking of inversion symmetry leads to sizable spin splittings and spontaneous diople moments than are larger than those in other Janus dichalcogenides. Moreover, our caluclations suggest that the work function of the Janus monolayers can be tuned by varying the content of the substituting chalcogen. Our work demonstrates that in-plane anisotropy provides additional flexibility in sub-layer engineering of 2D atomic crystals.
So Cloze yet so Far: N400 Amplitude is Better Predicted by Distributional Information than Human Predictability Judgements
Creators: name: Michaelov, James A.
name: Coulson, Seana
name: Bergen, Benjamin K.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: Information Theory (cs.IT)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: More predictable words are easier to process - they are read faster and elicit smaller neural signals associated with processing difficulty, most notably, the N400 component of the event-related brain potential. Thus, it has been argued that prediction of upcoming words is a key component of language comprehension, and that studying the amplitude of the N400 is a valuable way to investigate the predictions we make. In this study, we investigate whether the linguistic predictions of computational language models or humans better reflect the way in which natural language stimuli modulate the amplitude of the N400. One important difference in the linguistic predictions of humans versus computational language models is that while language models base their predictions exclusively on the preceding linguistic context, humans may rely on other factors. We find that the predictions of three top-of-the-line contemporary language models - GPT-3, RoBERTa, and ALBERT - match the N400 more closely than human predictions. This suggests that the predictive processes underlying the N400 may be more sensitive to the surface-level statistics of language than previously thought.
description: Accepted
Evidence of quadrupole and octupole deformations in $^{96}$Zr+$^{96}$Zr and $^{96}$Ru+$^{96}$Ru collisions at ultra-relativistic energies
Creators: name: Zhang, Chunjian
name: Jia, Jiangyong
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: In the hydrodynamic model description of heavy ion collisions, the elliptic flow $v_2$ and triangular flow $v_3$ are sensitive to the quadrupole deformation $β_2$ and octupole deformation $β_3$ of the colliding nuclei. The relations between $v_n$ and $β_n$ have recently been clarified and were found to follow a simple parametric form. The STAR Collaboration have just published precision $v_n$ data from isobaric $^{96}$Ru+$^{96}$Ru and $^{96}$Zr+$^{96}$Zr collisions, where they observe large differences in central collisions $v_{2,\mathrm{Ru}}>v_{2,\mathrm{Zr}}$ and $v_{3,\mathrm{Ru}}
description: 6 pages and 3 figures
Non-Hermitian skin effect in magnetic systems
Creators: name: Deng, Kuangyin
name: Flebus, Benedetta
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: Far from being limited to a trivial generalization of their Hermitian counterparts, non-Hermitian topological phases have gained widespread interest due to their unique properties. One of the most striking non-Hermitian phenomena is the skin effect, i.e., the localization of a macroscopic fraction of bulk eigenstates at a boundary, which underlies the breakdown of the bulk-edge correspondence. Here we investigate the emergence of the skin effect in magnetic insulating systems by developing a phenomenological approach to describing magnetic dissipation within a lattice model. Focusing on a spin-orbit-coupled van der Waals (vdW) ferromagnet with spin-nonconserving magnon-phonon interactions, we find that the magnetic skin effect emerges in an appropriate temperature regime. Our results suggest that the interference between Dzyaloshinskii-Moriya interaction (DMI) and nonlocal magnetic dissipation plays a key role in the accumulation of bulk states at the boundaries.
Schrödinger-Poisson Solitons: Perturbation Theory
Creators: name: Zagorac, J. Luna
name: Sands, Isabel
name: Padmanabhan, Nikhil
name: Easther, Richard
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Self-gravitating quantum matter may exist in a wide range of cosmological and astrophysical settings from the very early universe through to present-day boson stars. Such quantum matter arises in a number of different theories, including the Peccei-Quinn axion and UltraLight (ULDM) or Fuzzy (FDM) dark matter scenarios. We consider the dynamical evolution of perturbations to the spherically symmetric soliton, the ground state solution to the Schrödinger-Poisson system common to all these scenarios. We construct the eigenstates of the Schrödinger equation, holding the gravitational potential fixed to its ground state value. We see that the eigenstates qualitatively capture the properties seen in full ULDM simulations, including the soliton "breathing" mode, the random walk of the soliton center, and quadrupolar distortions of the soliton. We then show that the time-evolution of the gravitational potential and its impact on the perturbations can be well described within the framework of time-dependent perturbation theory. Applying our formalism to a synthetic ULDM halo reveals considerable mixing of eigenstates, even though the overall density profile is relatively stable. Our results provide a new analytic approach to understanding the evolution of these systems as well as possibilities for faster approximate simulations.
description: 12 pages, 11 figures; accepted to PRD The content and conclusions of Sec IV changed in the review process. Fig 9 was changed and Fig 10 added to illustrate our averaging procedure. Fig 11 changed significantly due to a tweak in the analysis pipeline. We added more discussion on the utility of our approach, more information on our numerical solver, and made small editorial changes
Towards Retrieval-based Conversational Recommendation
Creators: name: Manzoor, Ahtsham
name: Jannach, Dietmar
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: Conversational recommender systems have attracted immense attention recently. The most recent approaches rely on neural models trained on recorded dialogs between humans, implementing an end-to-end learning process. These systems are commonly designed to generate responses given the user's utterances in natural language. One main challenge is that these generated responses both have to be appropriate for the given dialog context and must be grammatically and semantically correct. An alternative to such generation-based approaches is to retrieve responses from pre-recorded dialog data and to adapt them if needed. Such retrieval-based approaches were successfully explored in the context of general conversational systems, but have received limited attention in recent years for CRS. In this work, we re-assess the potential of such approaches and design and evaluate a novel technique for response retrieval and ranking. A user study (N=90) revealed that the responses by our system were on average of higher quality than those of two recent generation-based systems. We furthermore found that the quality ranking of the two generation-based approaches is not aligned with the results from the literature, which points to open methodological questions. Overall, our research underlines that retrieval-based approaches should be considered an alternative or complement to language generation approaches.
description: 29 pages, 5 figures, 7 tables