April 2019 arXiv papers — page 112
Showing 11,101–11,200 of 12,989 papers
P. Vemareddy
Using time-sequence vector magnetic field observation from \textit{Helioseismic and Magnetic Imager}, we examined the connection of non-neutralized currents and the observed activity in 20 solar active-regions (ARs). The net current in a given magnetic polarity is algebraic sum of direct-current (DC) and return-current (RC) and the ratio $|DC/RC|$ is a measu
Luca Razzoli, Luca Ghirardi, Ilaria Siloi, Paolo Bordone
We put forward the idea of lattice quantum magnetometry, i.e. quantum sensing of magnetic fields by a charged (spinless) particle placed on a finite two-dimensional lattice. In particular, we focus on the detection of a locally static transverse magnetic field, either homogeneous or inhomogeneous, by performing ground state measurements. The system turns out
Eric Mitchell, Stefan Keselj, Sergiy Popovych, Davit Buniatyan
We propose a method of aligning a source image to a target image, where the transform is specified by a dense vector field. The two images are encoded as feature hierarchies by siamese convolutional nets. Then a hierarchy of aligner modules computes the transform in a coarse-to-fine recursion. Each module receives as input the transform that was computed by
Denis D. Sheka, Oleksandr V. Pylypovskyi, Pedro Landeros, Yuri Gaididei
Here, we present a micromagnetic theory of curvilinear ferromagnets, which allows discovering novel fundamental physical effects which were amiss. In spite of the firm confidence for more than 70 years, we demonstrate that there is an intimate coupling between volume and surface magnetostatic charges. Evenmore, the physics of curvilinear systems requires exi
Robert J. Hargreaves, Iouli E. Gordon, Laurence S. Rothman, Sergey A. Tashkun
This work describes the update of NO along with the incorporation of NO$_{2}$ and N$_{2}$O to the HITEMP database. Where appropriate, the HITRAN line lists for the same molecules have also been updated. This work brings the current number of molecules provided by HITEMP to seven. The initial line lists originating from \textit{ab initio} and semi-empirical m
Abdulelah Abuabat, Peter Brusilovsky
The purpose of this research is to study the possibility of identifying students, statistically, by analyzing their behavior in different consecutive activities. In this project, there are three different sorts of activities: animated example, basic example, and parameterized exercises. We extracted the behavior of each student from the log activities of the
Raphael Gontijo Lopes, David Ha, Douglas Eck, Jonathon Shlens
Dramatic advances in generative models have resulted in near photographic quality for artificially rendered faces, animals and other objects in the natural world. In spite of such advances, a higher level understanding of vision and imagery does not arise from exhaustively modeling an object, but instead identifying higher-level attributes that best summariz
Pourab Roy, Jason P. Fine, Michael R. Kosorok
In prevalent cohort studies where subjects are recruited at a cross-section, the time to an event may be subject to length-biased sampling, with the observed data being either the forward recurrence time, or the backward recurrence time, or their sum. In the regression setting, it has been shown that the accelerated failure time model for the underlying even
Xiao Fang, Li Luo, Qi-Man Shao
Correcting for skewness can result in more accurate tail probability approximations in the central limit theorem for sums of independent random variables. In this paper, we extend the theory to sums of local statistics of independent random variables and apply the result to $k$-runs, U-statistics, and subgraph counts in the Erdös-Rényi random graph. To prove
Shengfei Geng
Let $\mathbb{X}$ be a weighted projective line of tubular type and $\operatorname{coh}\mathbb{X}$ the category of coherent sheaves on $\mathbb{X}$. The main purpose of this note is to show that the subgraph of the tilting graph consisting of all basic tilting bundles in $\operatorname{coh}\mathbb{X}$ is connected. This yields an alternative proof for the con
Awni Hannun, Ann Lee, Qiantong Xu, Ronan Collobert
We propose a fully convolutional sequence-to-sequence encoder architecture with a simple and efficient decoder. Our model improves WER on LibriSpeech while being an order of magnitude more efficient than a strong RNN baseline. Key to our approach is a time-depth separable convolution block which dramatically reduces the number of parameters in the model whil
Martin Fitzi, Stefan Wenger
The Plateau-Douglas problem asks to find an area minimizing surface of fixed or bounded genus spanning a given finite collection of Jordan curves in Euclidean space. In the present paper we solve this problem in the setting of proper metric spaces admitting a local quadratic isoperimetric inequality for curves. We moreover obtain continuity up to the boundar
Tongtong Yuan, Weihong Deng, Jian Tang, Yinan Tang
Deep metric learning, which learns discriminative features to process image clustering and retrieval tasks, has attracted extensive attention in recent years. A number of deep metric learning methods, which ensure that similar examples are mapped close to each other and dissimilar examples are mapped farther apart, have been proposed to construct effective s
Olalla A. Castro-Alvaredo, Cecilia De Fazio, Benjamin Doyon, István M. Szécsényi
We consider two measures of entanglement, the logarithmic negativity and the entanglement entropy, between regions of space in excited states of many-body systems formed by a finite number of particle excitations. In parts I and II of the current series of papers, it has been shown in one-dimensional free-particle models that, in the limit of large system
Yi Jiang, Elliot Padgett, Robert Hovden, David A. Muller
Electron tomography (ET) has become a standard technique for 3D characterization of materials at the nano-scale. Traditional reconstruction algorithms such as weighted back projection suffer from disruptive artifacts with insufficient projections. Popularized by compressed sensing, sparsity-exploiting algorithms have been applied to experimental ET data and
Intensity Noise Optimization of a Mid-Infrared Frequency Comb Difference Frequency Generation Source
physics.opticsVinicius Silva de Oliveira, Axel Ruehl, Piotr Masłowski, Ingmar Hartl
We experimentally demonstrate in a difference-frequency generation mid-infrared frequency comb source the effect of temporal overlap between pump- and signal- pulse to the relative intensity noise (RIN) of the idler pulse. When scanning the temporal delay between our 130 fs long signal- and pump pulses, we observe a RIN minimum with a 3 dB width of 20 fs del
Qiang Song, Yoran Eli Pigeon, Kevin Heggarty
An approach for the optimization and synthesis of a phase-only faceted Fresnel type diffractive optical element (FDOE) generating 3D virtual images is proposed. The FDOE is a transmissive Fresnel type DOE array, which produces the perception of a customized floating 3D virtual image behind the FDOE when illuminated with a divergent monochromatic Light Emitte
Rabih Ajib, Armel pitelet, Rémi Pollès, Emmanuel Centeno
The group velocity of a plasmonic guided mode can be written as the ratio of the flux of the Poynting to the integral of the energy density along the profile of the mode. This theorem, linking the way energy propagates in metals to the properties of guided modes and Bloch modes in a multilayer, provides a unique physical insight in plasmonics. It allows to b
Hierarchical Trajectory Planning for Autonomous Driving in Low-speed Driving Scenarios Based on RRT and Optimization
cs.ROYuying Chen, Haoyang Ye, Ming Liu
Though great effort has been put into the study of path planning on urban roads and highways, few works have studied the driving strategy and trajectory planning in low-speed driving scenarios, e.g., driving on a university campus or driving through a housing or industrial estate. The study of planning in these scenarios is crucial as these environments ofte
Lam Pham
Let $G=\mathrm{SL}(2,\mathbb{Z})\ltimes\mathbb{Z}^2$ and $H=\mathrm{SL}(2,\mathbb{Z})$. We prove that the action $G\curvearrowright\mathbb{R}^2$ is uniformly non-amenable and that the quasi-regular representation of $G$ on $\ell^2(G/H)$ has a uniform spectral gap. Both results are a consequence of a uniform quantitative form of ping-pong for affine transform
Maritime Coverage Enhancement Using UAVs Coordinated with Hybrid Satellite-Terrestrial Networks
cs.ITXiangling Li, Wei Feng, Yunfei Chen, Cheng-Xiang Wang
Due to its agile maneuverability, unmanned aerial vehicles (UAVs) have shown great promise for ondemand communications. In practice, UAV-aided aerial base stations are not separate. Instead, they rely on existing satellites/terrestrial systems for spectrum sharing and efficient backhaul. In this case, how to coordinate satellites, UAVs and terrestrial system
Multivariate outlier detection based on a robust Mahalanobis distance with shrinkage estimators
stat.MEElisa Cabana, Rosa E. Lillo, Henry Laniado
A collection of robust Mahalanobis distances for multivariate outlier detection is proposed, based on the notion of shrinkage. Robust intensity and scaling factors are optimally estimated to define the shrinkage. Some properties are investigated, such as affine equivariance and breakdown value. The performance of the proposal is illustrated through the compa
Noga Alon, Colin Defant
The direct product of graphs $G_1,\ldots,G_n$ is the graph with vertex set $V(G_1)\times\cdots\times V(G_n)$ in which two vertices $(g_1,\ldots,g_n)$ and $(g_1',\ldots,g_n')$ are adjacent if and only if $g_i$ is adjacent to $g_i'$ in $G_i$ for all $i$. Building off of the recent work of Brakensiek, we prove an optimal vertex isoperimetric inequal
Andrew Aberdein
The traditional view of evidence in mathematics is that evidence is just proof and proof is just derivation. There are good reasons for thinking that this view should be rejected: it misrepresents both historical and current mathematical practice. Nonetheless, evidence, proof, and derivation are closely intertwined. This paper seeks to tease these concepts a
Rui Ma, Amal A. Alahmadi, Taisir E. H. El-Gorashi, Jaafar M. H. Elmirghani
Along with the development of Internet of Things (IoT) and the rise of fog computing, more new joint technologies have been proposed. Vehicular Ad-hoc Networks (VANET) are one of the emergent technologies that come with a very promising role, where the spare processing capabilities of vehicles can be exploited. In this paper, we propose a fog architecture to
T. Banks
We argue that the infall time to the singularity in the interior of a black hole, is always related to a classical thermalization time. This indicates that singularities are related to the equilibration of infalling objects with the microstates of the black hole, but only in the sense of classical equilibration. When the singularity is reached, the quantum s
A Gromov-Hausdorff convergence theorem of surfaces in $\mathbb{R}^n$ with small total curvature
math.DGJianxin Sun, Jie Zhou
In this paper, we mainly study the compactness and local structure of immersing surfaces in $\mathbb{R}^n$ with local uniform bounded area and small total curvature $\int_{Σ\cap B_1(0)} |A|^2$. A key ingredient is a new quantity which we call isothermal radius. Using the estimate of the isothermal radius we establish a compactness theorem of such surfaces in
High-temperature deep-level transient spectroscopy system for defect studies in wide-bandgap semiconductors
cond-mat.mtrl-sciS. Majdi, M. Gabrysch, N. Suntornwipat, F. Burmeister
Full investigation of deep defect states and impurities in wide-bandgap materials by employing commercial transient capacitance spectroscopy is a challenge, demanding very high temperatures. Therefore, a high-temperature deep-level transient spectroscopy (HT-DLTS) system was developed for measurements up to 1100 K. The upper limit of the temperature range al
Mauro C. Beltrametti, Cristina Campi, Anna Maria Massone, Maria-Laura Torrente
In the framework of the Hough transform technique to detect curves in images, we provide a bound for the number of Hough transforms to be considered for a successful optimization of the accumulator function in the recognition algorithm. Such a bound is consequence of geometrical arguments. We also show the robustness of the results when applied to synthetic
Hisashi Inoue, Minyong Han, Mengli Hu, Takehito Suzuki
Realizing quantum materials in few atomic layer morphologies is a key to both observing and controlling a wide variety of exotic quantum phenomena. This includes topological electronic materials, where the tunability and dimensionality of few layer materials have enabled the detection of $Z_2$, Chern, and Majorana phases. Here, we report the development of a
Arran Fernandez, Ceren Ustaoğlu, Mehmet Ali Özarslan
The theory of fractional calculus has developed in a number of directions over the years, including: the formulation of multiple different definitions of fractional differintegration; the extension of various properties of standard calculus into the fractional scenario; the application of fractional differintegrals to assorted special functions. Recently, a
The emergence of sequence-dependent structural motifs in stretched, torsionally constrained DNA
q-bio.BMJack W Shepherd, Robert J Greenall, Matt I J Probert, Agnes Noy
The double-helical structure of DNA results from canonical base pairing and stacking interactions. However, variations from steady-state conformations result from mechanical perturbations in cells. These different topologies have physiological relevance but their dependence on sequence remains unclear. Here, we use molecular dynamics simulations to show that
Segmentation of the Prostatic Gland and the Intraprostatic Lesions on Multiparametic MRI Using Mask-RCNN
cs.CVZhenzhen Dai, Eric Carver, Chang Liu, Joon Lee
Prostate cancer (PCa) is the most common cancer in men in the United States. Multiparametic magnetic resonance imaging (mp-MRI) has been explored by many researchers to targeted prostate biopsies and radiation therapy. However, assessment on mp-MRI can be subjective, development of computer-aided diagnosis systems to automatically delineate the prostate glan
Mariano Pascale, Giovanni Miano, Roberto Tricarico, Carlo Forestiere
The plasmon hybridization theory is based on a quasi-electrostatic approximation of the Maxwell's equations. It does not take into account magnetic interactions, retardation effects, and radiation losses. Magnetic interactions play a dominant role in the scattering from dielectric nanoparticles. The retardation effects play a fundamental role in the coup
Fat Tails in Financial Return Distributions Revisited: Evidence from the Korean Stock Market
q-fin.GNCheoljun Eom, Taisei Kaizoji, Enrico Scalas
This study empirically re-examines fat tails in stock return distributions by applying statistical methods to an extensive dataset taken from the Korean stock market. The tails of the return distributions are shown to be much fatter in recent periods than in past periods and much fatter for small-capitalization stocks than for large-capitalization stocks. Af
Noise-Level Estimation from Single Color Image Using Correlations Between Textures in RGB Channels
cs.CVAkihiro Nakamura, Michihiro Kobayashi
We propose a simple method for estimating noise level from a single color image. In most image-denoising algorithms, an accurate noise-level estimate results in good denoising performance; however, it is difficult to estimate noise level from a single image because it is an ill-posed problem. We tackle this problem by using prior knowledge that textures are
Mie Andersen, Chiara Panosetti, Karsten Reuter
This review article is intended as a practical guide for newcomers to the field of kinetic Monte Carlo (KMC) simulations, and specifically to lattice KMC simulations as prevalently used for surface and interface applications. We will provide worked out examples using the kmos code, where we highlight the central approximations made in implementing a KMC mode
Impact of single and double oxygen vacancies on electronic transport in Fe/MgO/Fe magnetic tunnel junctions
cond-mat.mtrl-sciBeata Taudul, M. Bowen, M. Alouani
To study the impact of oxygen vacancies on spin-polarized transport, we have computed the electronic and transport properties of single (F centers) and paired (M centers) oxygen vacancies using density functional theory. These point defects can generate barrier heights as low as 0.4V for FeCo electrodes irrespective of the defect's spatial position withi
Minye Wu, Haibin Ling, Ning Bi, Shenghua Gao
Recent progresses in visual tracking have greatly improved the tracking performance. However, challenges such as occlusion and view change remain obstacles in real world deployment. A natural solution to these challenges is to use multiple cameras with multiview inputs, though existing systems are mostly limited to specific targets (e.g. human), static camer
J. A. Carrillo, K. Grunert, H. Holden
We analyze stability of conservative solutions of the Cauchy problem on the line for the Camassa--Holm (CH) equation. Generically, the solutions of the CH equation develop singularities with steep gradients while preserving continuity of the solution itself. In order to obtain uniqueness, one is required to augment the equation itself by a measure that repre
Chen Wang
In this paper, we confirm some congruences conjectured by V.J.W. Guo and M.J. Schlosser recently. For example, we show that for primes $p>3$, $$ \sum_{k=0}^{p-1}(2pk-2k-1)\frac{\left(\frac{-1}{p-1}\right)_k^{2p-2}}{(k!)^{2p-2}}\equiv0\pmod{p^5}. $$
Arnaud Dapogny, Kévin Bailly, Matthieu Cord
Face Alignment is an active computer vision domain, that consists in localizing a number of facial landmarks that vary across datasets. State-of-the-art face alignment methods either consist in end-to-end regression, or in refining the shape in a cascaded manner, starting from an initial guess. In this paper, we introduce DeCaFA, an end-to-end deep convoluti
Mosbah Difallah, Alexander Szameit, Marco Ornigotti
We present a method, based on Feynman path integrals, to describe the propagation and properties of the quantised electromagnetic field in an arbitrary, nonlinear medium. We provide a general theory, valid for any order of optical nonlinearity, and we then specialise the the case of second order nonlinear processes. In particular, we show, that second-order
Lisa Beinborn, Samira Abnar, Rochelle Choenni
Language-brain encoding experiments evaluate the ability of language models to predict brain responses elicited by language stimuli. The evaluation scenarios for this task have not yet been standardized which makes it difficult to compare and interpret results. We perform a series of evaluation experiments with a consistent encoding setup and compute the res
Jozef Kratica, Vladimir Filipovic, Dragan Matic, Aleksandar Kartelj
Due to their importance in practice, dominating set problems in graphs have been greatly studied in past and different formulations of these problems are presented in literature. This paper's focus is on two problems: weakly convex dominating set problem (WCVXDSP) and convex dominating set problem (CVXDSP). It introduces two integer linear programming (I
Time Entanglement between a Photon and a Spin Wave in a Multimode Solid-state Quantum Memory
quant-phKutlu Kutluer, Emanuele Distante, Bernardo Casabone, Stefano Duranti
The generation and distribution of entanglement are key resources in quantum repeater schemes. Temporally multiplexed systems offer time-bin encoding of quantum information which provides robustness against decoherence in fibers, crucial in long distance communication. Here we demonstrate the direct generation of entanglement in time between a photon and a c
Christopher Walker, Efstratios Mitridis, Thomas Kreiner, Hadi Eghlidi
Surface fogging is a common phenomenon that can have significant and detrimental effects on surface transparency and visibility. It affects the performance in a wide range of applications including windows, windshields, electronic displays, cameras, mirrors, and eyewear. A host of ongoing research is aimed at combating this problem by understanding and devel
Angela D. V. Di Virgilio, Nicolò Beverini, Giorgio Carelli, Donatella Ciampini
Inertial sensors stimulate very large interest, not only for their application but also for fundamental physics tests. Ring laser gyros, which measure angular rotation rate, are certainly among the most sensitive inertial sensors, with excellent dynamic range and bandwidth. Large area ring laser gyros are routinely able to measure fractions of prad/s, with h
S. Hamidreza Kasaei, Nima Shafii, Luis Seabra Lopes, Ana Maria Tome
Service robots are expected to autonomously and efficiently work in human-centric environments. For this type of robots, object perception and manipulation are challenging tasks due to need for accurate and real-time response. This paper presents an interactive open-ended learning approach to recognize multiple objects and their grasp affordances concurrentl
Armelle Brun, Geoffray Bonnin, Sylvain Castagnos, Azim Roussanaly
This paper presents the METAL project, an ongoing French open Learning Analytics (LA) project for secondary school, that aims at improving the quality of the learning process. The originality of METAL is that it relies on research through exploratory activities and focuses on all the aspects of a Learning Analytics implementation. This large-scale project in
Discontinuous Galerkin Isogeometric Analysis for Elliptic Problems with Discontinuous Coefficients on Surfaces
math.NAStephen Edward Moore
This paper is concerned with using discontinuous Galerkin isogeometric analysis (dGIGA) as a numerical treatment of Diffusion problems on orientable surfaces $Ω\subset \mathbb{R}^3$. The computational domain or surface considered consist of several non-overlapping sub-domains or patches which are coupled via an interior penalty scheme. In Langer and Moore U.
Sandro Sozzo
Despite the impressive success of quantum structures to model long-standing human judgement and decision puzzles, the {\it quantum cognition research programme} still faces challenges about its explanatory power. Indeed, quantum models introduce new parameters, which may fit empirical data without necessarily explaining them. Also, one wonders whether more g
Anomalous high-magnetic field electronic state of the nematic superconductors FeSe$_{1-x}$S$_x$
cond-mat.supr-conM. Bristow, P. Reiss, A. A. Haghighirad, Z. Zajicek
Understanding superconductivity requires detailed knowledge of the normal electronic state from which it emerges. A nematic electronic state that breaks the rotational symmetry of the lattice can potentially promote unique scattering relevant for superconductivity. Here, we investigate the normal transport of superconducting FeSe$_{1-x}$S$_x$ across a nemati
Stephen Donkin, Samuel Martin
Let $G$ be the special linear group of degree $2$ over an algebraically closed field $K$. Let $E$ be the natural module and $S^rE$ the $r$th symmetric power. We consider here, for $r,s\geq 0$, the tensor product of $S^rE$ and the dual of $S^sE$. In characteristic zero this tensor product decomposes according to the Clebsch-Gordan formula. We consider here th
Cheng Deng, Zhao Li, Xinbo Gao, Dacheng Tao
As JPEG is the most widely used image format, the importance of tampering detection for JPEG images in blind forensics is self-evident. In this area, extracting effective statistical characteristics from a JPEG image for classification remains a challenge. Effective features are designed manually in traditional methods, suggesting that extensive labor-consum
Shao-Feng Ge, Hitoshi Murayama
A natural realization of CPT violation in neutrino oscillation can arise due to the coupling to a light scalar or vector dark matter (DM). The dark non-standard interaction (NSI) is associated with the $γ_0$ matrix in neutrino's effective propagator and hence corrects the neutrino Hamiltonian as dark matter potential, in the same way as the ordinary matt
Aymeric Delteil, Chun Tat Ngai, Thomas Fink, Ataç İmamoğlu
The second-order correlation function of light $g^{(2)}(τ)$ constitutes a pivotal tool to quantify the quantum behavior of an emitter and in turn its potential for quantum information applications. The experimentally accessible time resolution of $g^{(2)}(τ)$ is usually limited by the jitter of available single photon detectors. Here, we present a versatile
Superconductivity-driven magnetization modulation in YBa2Cu3O7-δ /SrTiO3/La0.67Sr0.33MnO3 heterostructures
cond-mat.supr-conSurendra Singh, Harsh Bhatt, Yogesh Kumar, C. L. Prajapat
Using spin polarized neutron reflectivity experiments, we demonstrate an unusual proximity behaviour when the superconductor (SC) and the ferromagnet (FM) are coupled through an insulator (I) in YBa2Cu3O7-δ (SC)/SrTiO3 (I)/La0.67Sr0.33MnO3 (FM) heterostructures. We have observed an unexpected magnetic modulation at the interface region of the FM below the su
Jean-Baptiste Thomazo, Javier Contreras Pastenes, Christopher Pipe, Benjamin Le Révérend
An experimental biomimetic tongue-palate system has been developed to probe human in-mouth texture perception. Model tongues are made from soft elastomers patterned with fibrillar structures analogue to human filiform papillae. The palate is represented by a rigid flat plate parallel to the plane of the tongue. To probe the behavior under physiological flow
Noninvasive linear fluorescence imaging through scattering media via wavefront shaping
physics.opticsAnat Daniel, Dan Oron, Yaron Silberberg
We demonstrate focusing and imaging through a scattering medium noninvasively by using wavefront shaping. Our concept is based on utilizing the spatial fluorescence contrast which naturally exists in the hidden target object. By scanning the angle of incidence of the illuminating laser beam and maximizing the variation of the detected fluorescence signal fro
Q. B. Chen, N. Kaiser, Ulf-G. Meißner, J. Meng
The behavior of the collective rotor in the chiral motion of triaxially deformed nuclei is investigated using the particle rotor model by transforming the wave functions from the $K$-representation to the $R$-representation. After examining the energy spectra of the doublet bands and their energy differences as functions of the triaxial deformation, the angu
Robust and accurate computational estimation of the polarizability tensors of macromolecules
physics.chem-phMuhamed Amin, Hebatallah Samy, Jochen Küpper
Alignment of molecules through electric fields minimizes the averaging over orientations, e. g., in single particle imaging experiments. The response of molecules to external ac electric fields is governed by their polarizability tensor, which is usually calculated using quantum-chemistry methods. These methods are not feasible for large molecules. Here, we
Importance of vdW and long-range exchange interactions to DFT-predicted docking energies between plumbagin and cyclodextrins
cond-mat.mtrl-sciTom Ichibha, Ornin Srihakulung, Guo Chao, Adie Tri Hanindriyo
We calculated the docking energies between plumbagin and cyclodextrins, using density functional theory (DFT) with several functionals and some semi-empirical methods. Our DFT results revealed that GD3 dispersion force correction significantly improves the reliability of prediction. Also sufficient amount of long-range exchange is important to make it reliab
Luis Barba, Alexander Pilz, Patrick Schnider
Assume you have a pizza consisting of four ingredients (e.g., bread, tomatoes, cheese and olives) that you want to share with your friend. You want to do this fairly, meaning that you and your friend should get the same amount of each ingredient. How many times do you need to cut the pizza so that this is possible? We will show that two straight cuts always
Mikhail R. Gadelha, Felipe R. Monteiro, Enrico Steffinlongo, Lucas C. Cordeiro
We describe and evaluate a novel k-induction proof rule called bidirectional k-induction (bkind), which substantially improves the k-induction bug-finding capabilities. Particularly, bkind exploits the counterexamples generated by the over-approximation step to derive new properties and feed them back to the bounded model checking procedure. We also combine
Md Rushdie Ibne Islam, Ankur Bansal, Chong Peng
This paper presents numerical simulations of metal machining processes with Eulerian and Total Lagrangian Smoothed Particle Hydrodynamics (SPH). Being a mesh-free method, SPH can conveniently handle large deformation and material separation. However, the Eulerian SPH (ESPH) in which the kernel functions are computed based on the current particle positions su
Benjamin K. Smeltzer, Eirik Æsøy, Simen Å. Ellingsen
We report experimental observations of two canonical surface wave patterns --- ship waves and ring waves --- skewed by sub-surface shear, thus confirming effects predicted by recent theory. Observed ring waves on a still surface with sub-surface shear current are strikingly asymmetric, an effect of strongly anisotropic wave dispersion. Ship waves for motion
Pressure Shifts in High-Precision Hydrogen Spectroscopy: II. Impact Approximation and Monte-Carlo Simulations
physics.atom-phA. Matveev, N. Kolachevsky, C. M. Adhikari, U. D. Jentschura
We investigate collisional shifts of spectral lines involving excited hydrogenic states, where van der Waals coefficients have recently been shown to have large numerical values when expressed in atomic units. Particular emphasis is laid on the recent hydrogen 2S-4P experiment (and an ongoing 2S-6P experiment) in Garching, but numerical input data are provid
John Mitros, Brian Mac Namee
The ubiquity of machine learning based predictive models in modern society naturally leads people to ask how trustworthy those models are? In predictive modeling, it is quite common to induce a trade-off between accuracy and interpretability. For instance, doctors would like to know how effective some treatment will be for a patient or why the model suggeste
Thomas A. Mellan, Andrew I. Duff, Blazej Grabowski, Michael W. Finnis
We propose an approach to calculate the anharmonic part of the volumetric-strain and temperature dependent free energy of a crystal. The method strikes an effective balance between accuracy and computational efficiency, showing a $\times10$ speed-up on comparable free energy approaches at the level of density functional theory, with average errors less than
Non-Hermitian Weyl Semimetals: Non-Hermitian Skin Effect and non-Bloch Bulk-Boundary Correspondence
cond-mat.mes-hallXiaosen Yang, Yang Cao, Yunjia Zhai
We investigate novel features of three dimensional non-Hermitian Weyl semimetals, paying special attention to its unconventional bulk-boundary correspondence. We use the non-Bloch Chern numbers as the tool to obtain the topological phase diagram, which is also confirmed by the energy spectra from our numerical results. It is shown that, in sharp contrast to
Chi-Yee Cheung
The proof of the No-Go Theorem of unconditionally secure quantum bit commitment depends on the assumption that Alice knows every detail of the protocol, including the probability distributions associated with all the random variables generated by Bob. We argue that this condition may not be universally satisfied. In fact it can be shown that when Bob is allo
\textit{Ab initio} study of Bi-based half Heusler alloys as potential thermoelectric prospects
cond-mat.mtrl-sciSapna Singh, Mohd Zeeshan, Jeroen van den Brink, Hem C. Kandpal
We investigated six heavy element bismuth-based 18-VEC half-Heusler alloys CoTiBi, CoZrBi, CoHfBi, FeVBi, FeNbBi, and FeTaBi by first principles approach, in search of better thermoelectric prospects. The motivation is driven by expected lower thermal conductivity and the recent discovery of CoZrBi-based materials. Significantly, our calculated power factor
Internal energy dissipation in Enceladus's ocean from tides and libration and the role of inertial waves
physics.geo-phJ. Rekier, A. Trinh, S. A. Triana, V. Dehant
Enceladus is characterised by a south polar hot spot associated with a large outflow of heat, the source of which remains unclear. We compute the viscous dissipation resulting from tidal and libration forcing in the moon's subsurface ocean using the linearised Navier-Stokes equation in a 3-dimensional spherical model. We conclude that libration is the do
Taofiq K. Paraïso, Innocenzo De Marco, Thomas Roger, Davide G. Marangon
Quantum key distribution (QKD) has convincingly been proven compatible with real life applications. Its wide-scale deployment in optical networks will benefit from an optical platform that allows miniature devices capable of encoding the necessarily complex signals at high rates and with low power consumption. While photonic integration is the ideal route to
First-principles investigations of orthorhombic-cubic phase transition and its effect on thermoelectric properties in cobalt-based ternary alloys
cond-mat.mtrl-sciSapna Singh, Mohd Zeeshan, Jeroen van den Brink, Hem C. Kandpal
We screened six cobalt-based 18-VEC systems CoVSi, CoNbSi, CoTaSi (Si-group) and CoVGe, CoNbGe, CoTaGe (Ge-group) by the first-principles approach, with the motivation of stabilizing these orthorhombic phases into the cubic symmetry -- favorable for thermoelectrics. Remarkably, it was found that the Ge-group is energetically more favorable in the cubic symme
M. N. Yudina, V. N. Zadorozhnyi, E. B. Yudin
The problem of calculating the frequencies of network motifs on three and four nodes in large networks is considered. Telecommunications networks, cell molecular networks are investigated. The sizes of the investigated networks are hundreds of thousands of nodes and connections. These networks are represented in the form of directed and undirected simple gra
Wei Gao, Weifan Wang, Juan L. G. Guirao
In Gao's previous work, the authors determined several graph degree conditions of a graph which admits fractional factor in particular settings. It was revealed that these degree conditions are tight if $b=f(x)=g(x)=a$ for all vertices $x$ in $G$. In this paper, we continue to discuss these degree conditions for admitting fractional factor in the setting
Yu Zeng, Ahmed Al-Quzweeni, Taisir E. H. Elgorashi, Jaafar M. H. Elmirghani
Fog radio access network (F-RAN) and virtualisation are promising technologies for 5G networks. In F-RAN, the fog and cloud computing are integrated where the conventional C-RAN functions are diverged to the edge devices of radio access networks. F-RAN is adopted to mitigate the burden of front-haul and improve the end to end (E2E) latency. On other hand, vi
David Puljiz, Katharina S. Riesterer, Björn Hein, Torsten Kröger
Having a precise and robust transformation between the robot coordinate system and the AR-device coordinate system is paramount during human-robot interaction (HRI) based on augmented reality using Head mounted displays (HMD), both for intuitive information display and for the tracking of human motions. Most current solutions in this area rely either on the
V. N. Zadorozhnyi, E. B. Yudin
The methods of non-homogeneous random graphs calibration are developed for social networks simulation. The graphs are calibrated by the degree distributions of the vertices and the edges. The mathematical foundation of the methods is formed by the theory of random graphs with the nonlinear preferential attachment rule and the theory of Erdos-Renyi random gra
Is it Possible to Disregard Obsolete Requirements? - An Initial Experiment on a Potentially New Bias in Software Effort Estimation
cs.SELucas Gren, Richard Berntsson Svensson, Michael Unterkalmsteiner
Effort estimation is a complex area in decision-making, and is influenced by a diversity of factors that could increase the estimation error. The effects on effort estimation accuracy of having obsolete requirements in specifications have not yet been studied. This study aims at filling that gap. A total of 150 students were asked to provide effort estimates
Cristian E. Gutierrez, Federico Tournier
We establish local $C^{1,α}$ estimates for one source near field refractors under structural assumptions on the target, and with no assumptions on the smoothness of the densities.
E. B. Yudin
Paper proposes a model of large networks based on a random preferential attachment graph with addition of complete subgraphs (cliques). The proposed model refers to models of random graphs following the nonlinear preferential attachment rule and takes into account the possibility of «adding» entire communities of nodes to the network. In the derivation of th
Lucas Gren
Brooks' Law is often referred to in practice and states that adding manpower to a late software project makes it even later. Brooks' himself gave three explanation only related to concrete task-related issues, like introducing new members to the work being done, communication overheads, or difficulty dividing some programming tasks. Through a descrip
Comparison between isothermal collision-streaming and finite-difference lattice Boltzmann models
physics.comp-phGiuseppe Negro, Sergiu Busuioc, Victor E. Ambrus, Giuseppe Gonnella
We present here a comparison between collision-streaming and finite-difference lattice Boltzmann (LB) models. This study provides a derivation of useful formulae which help one to properly compare the simulation results obtained with both LB models. We consider three physical problems: the shock wave propagation, the damping of shear waves, and the decay of
On the connection between sliding friction and phonon lifetimes: Thermostat induced thermolubricity effects in molecular dynamics simulations
cond-mat.mtrl-sciRichard L. C. Vink
A typical nanotribology simulation setup is the semi-infinite substrate, featuring a sliding bead on top, and with the lower substrate layers thermostatted to control temperature. A challenge is dealing with phonons that backreflect from the substrate lower boundary, as these will artificially reduce the friction FR acting on the sliding bead. One proposed s
Evgeny Bobrov, Antonio Bucchiarone, Alfredo Capozucca, Nicolas Guelfi
DevOps processes comply with principles and offer practices with main objective to support efficiently the evolution of IT systems. To be efficient a DevOps process relies on a set of integrated tools. DevOps is the first required competency together with Agile Method required by the industry. DevOps processes are sharing many aspects with microservices appr
Group development and group maturity when building agile teams: A qualitative and quantitative investigation at eight large companies
cs.SELucas Gren, Richard Torkar, Robert Feldt
The agile approach to projects focuses more on close-knit teams than traditional waterfall projects, which means that aspects of group maturity become even more important. This psychological aspect is not much researched in connection to the building of an "agile team." The purpose of this study is to investigate how building agile teams is connected
Trying to Increase the Mature Use of Agile Practices by Group Development Psychology Training - An Experiment
cs.SELucas Gren, Alfredo Goldman
There has been some evidence that agility is connected to the group maturity of software development teams. This study aims at conducting group development psychology training with student teams, participating in a project course at university, and compare their group effectiveness score to their agility usage over time in a longitudinal design. Seven XP stu
Lucas Gren
There is a diversity of models explaining organizational culture and how these complex aspects can be addressed in connection to organizational change efforts. This workshop paper claims that models already exist for dealing with the cultural change that an agile transition is in the software engineering context. Instead of realizing this again through agile
Damien Sileo, Tim Van-De-Cruys, Camille Pradel, Philippe Muller
Various NLP problems -- such as the prediction of sentence similarity, entailment, and discourse relations -- are all instances of the same general task: the modeling of semantic relations between a pair of textual elements. A popular model for such problems is to embed sentences into fixed size vectors, and use composition functions (e.g. concatenation or s
Inigo Jauregi Unanue, Ehsan Zare Borzeshi, Nazanin Esmaili, Massimo Piccardi
Regularization of neural machine translation is still a significant problem, especially in low-resource settings. To mollify this problem, we propose regressing word embeddings (ReWE) as a new regularization technique in a system that is jointly trained to predict the next word in the translation (categorical value) and its word embedding (continuous value).
Agility Measurements Mismatch: A Validation Study on Three Agile Team Assessments in Software Engineering
cs.SEKonstantinos Chronis, Lucas Gren
Many tools have been created for measuring the agility of software teams, thus creating a saturation in the field. Three agile measurement tools were selected in order to validate whether they yield sim-ilar results. The surveys of the tools were given to teams in Company A (N = 30). The questions were grouped into agile practices which were checked for corr
Neeru Dubey, Shreya Ghosh, Abhinav Dhall
Automatic eye gaze estimation has interested researchers for a while now. In this paper, we propose an unsupervised learning based method for estimating the eye gaze region. To train the proposed network "Ize-Net" in self-supervised manner, we collect a large `in the wild' dataset containing 1,54,251 images from the web. For the images in the dat
Useful Statistical Methods for Human Factors Research in Software Engineering: A Discussion on Validation with Quantitative Data
cs.SELucas Gren, Alfredo Goldman
In this paper we describe the usefulness of statistical validation techniques for human factors survey research. We need to investigate a diversity of validity aspects when creating metrics in human factors research, and we argue that the statistical tests used in other fields to get support for reliability and construct validity in surveys, should also be a
Giuseppe Dibitetto, Nicolò Petri
We summarize the results and the ideas in 1707.06152, 1707.06154, 1807.07768 where new warped $\mathrm{AdS}_3$ backgrounds are derived in massive IIA string theory by uplifting exact solutions in $\mathcal N=1$, $d=7$ and $\mathcal N=(1,1)$, $d=6$ gauged supergravities. These solutions are respectively asymptotically $\mathrm{AdS}_7$ and $\mathrm{AdS}_6$ and
Active Transfer Learning Network: A Unified Deep Joint Spectral-Spatial Feature Learning Model For Hyperspectral Image Classification
cs.CVCheng Deng, Yumeng Xue, Xianglong Liu, Chao Li
Deep learning has recently attracted significant attention in the field of hyperspectral images (HSIs) classification. However, the construction of an efficient deep neural network (DNN) mostly relies on a large number of labeled samples being available. To address this problem, this paper proposes a unified deep network, combined with active transfer learni
Lucas Gren, Richard Torkar, Robert Feldt
The focus on psychology has increased within software engineering due to the project management innovation "agile development processes". The agile methods do not explicitly consider group development aspects; they simply assume what is described in group psychology as mature groups. This study was conducted with 45 employees and their twelve manager
Barak Beilin, David Burshtein
The problem of communication over binary dirty paper (DP) using nested polar codes is considered. An improved scheme, focusing on low delay, short to moderate blocklength communication is proposed. Successive cancellation list (SCL) decoding with properly defined CRC is used for channel coding, and SCL encoding without CRC is used for source coding. The perf