May 2020 arXiv papers — page 5
Showing 401–500 of 15,175 papers
Masud Mansuripur
The Fourier transform operation is an important conceptual as well as computational tool in the arsenal of every practitioner of physical and mathematical sciences. We discuss some of its applications in optical science and engineering, with the goal of providing a broad perspective on the intimate relation between the physical and mathematical concepts that
GPU-based parallel simulations of the Gatenby-Gawlinski model with anisotropic, heterogeneous acid diffusion
physics.med-phCorrado Mascia, Donato Pera, Chiara Simeoni
We introduce a variant of the Gatenby-Gawlinski model for acid-mediated tumor invasion, accounting for anisotropic and heterogeneous diffusion of the lactic acid across the surrounding healthy tissues. Numerical simulations are performed for two-dimensional data by employing finite volume schemes on staggered Cartesian grids, and parallel implementation thro
Ioannis Arapakis, Luis A. Leiva
Tracking mouse cursor movements can be used to predict user attention on heterogeneous page layouts like SERPs. So far, previous work has relied heavily on handcrafted features, which is a time-consuming approach that often requires domain expertise. We investigate different representations of mouse cursor movements, including time series, heatmaps, and traj
New Analytic Solutions for Galaxy Evolution II: Wind Recycling, Galactic Fountains and Late-Type Galaxies
astro-ph.GAA. Lapi, L. Pantoni, L. Boco, L. Danese
We generalize the analytic solutions presented in Pantoni et al. (2019) by including a simple yet effective description of wind recycling and galactic fountains, with the aim of self-consistently investigating the spatially-averaged time evolution of the gas, stellar, metal, and dust content in disc-dominated late-type galaxies (LTGs). Our analytic solutions
Z. Yousaf
The aim of this paper is to explore the complexity factor (CF) for those self-gravitating relativistic spheres whose evolution proceeds non-dynamically. We are adopting the definition of CF mentioned in \cite{PhysRevD.97.044010}, modifying it to the static spherically symmetric case, within the framework of a modified gravity theory (the Palatini $f(R)$ theo
Debraj Chandra, Pratulananda Das, Subhankar Das
This article is a continuation of the study of bornological open covers and related selection principles in metric spaces done in (Chandra et al. 2020) using the idea of strong uniform convergence (Beer and Levi, 2009) on bornology. Here we explore further ramifications, presenting characterizations of various selection principles related to certain classes
Yujie Hu, Fahui Wang
Excess or wasteful commuting is measured as the proportion of actual commute that is over minimum (optimal) commute when assuming that people could freely swap their homes and jobs in a city. Studies usually rely on survey data to define actual commute, and measure the optimal commute at an aggregate zonal level by linear programming (LP). Travel time from a
Maxim Dvornikov
Spin oscillations of neutrinos, gravitationally scattered off a black hole (BH), are studied. The cases of nonrotating and rotating BHs are analyzed. We derive the analytic expressions for the transition and survival probabilities of spin oscillations when neutrinos interact with these gravitational backgrounds. The obtained transition probabilities depend o
Emmanuel Jordy Menvouta, Sven Serneels, Tim Verdonck
The direpack package aims to establish a set of modern statistical dimension reduction techniques into the Python universe as a single, consistent package. The dimension reduction methods included resort into three categories: projection pursuit based dimension reduction, sufficient dimension reduction, and robust M estimators for dimension reduction. As a c
Aina Niemetz, Mathias Preiner
In this paper, we present Bitwuzla, our Satisfiability Modulo Theories (SMT) solver for the theories of bit-vectors, floating-points, arrays and uninterpreted functions and their combinations. We discuss selected features and provide details of its configuration and participation in the 2020 edition of the annual SMT competition.
Suparna Biswas, Dibyendu Shee, B. K. Guha, Saibal Ray
In the current article, we study anisotropic spherically symmetric strange star under the background of $f(R,T)$ gravity using the metric potentials of Tolman-Kuchowicz type~\cite{Tolman1939,Kuchowicz1968} as $λ(r)=\ln(1+ar^2+br^4)$ and $ν(r)=Br^2+2\ln C$ which are free from singularity, satisfy stability criteria and also well behaved. We calculate the valu
A. Saha, S. Ghose
We discuss Tsallis holographic dark energy (THDE) model in higher dimension. An interacting dark energy model is proposed with Generalized Chaplygin Gas (GCG) in the framework of Compact Kaluza-Klein gravity. It is shown that a stable configuration can be found in the present epoch which is also compatible with the observed value of the density parameter. It
Constructive description of Hardy-Sobolev spaces in strictly pseudoconvex domains with minimal smoothness
math.CVAleksandr Rotkevich
Let $Ω\subset\mathbb{C}^n$ be a strictly pseudoconvex Runge domain with $C^2$-smooth defining function, $l\in\mathbb{N},$ $p\in(1,\infty).$ We prove that the holomorphic function $f$ has derivatives of order $l$ in $H^p(Ω)$ if and only if there exists a sequence on polynomials $P_n$ of degree $n$ such that $\sum\limits_{k=1}^{\infty}2^{2lk}\left\lvert f(z)-P
Optical spectroscopy and photometry of main-belt asteroids with a high orbital inclination
astro-ph.EPAya Iwai, Yoichi Itoh, Tsuyoshi Terai, Ranjan Gupta
We carried out low-resolution optical spectroscopy of 51 main-belt asteroids, most of which have highly-inclined orbits. They are selected from D-type candidates in the SDSS-MOC 4 catalog. Using the University of Hawaii 2.2 m telescope and the Inter-University Centre for Astronomy and Astrophysics 2 m telescope in India, we determined the spectral types of 3
A. Aguilar-Arevalo, M. Aoki, M. Blecher, D. I. Britton
The rare pion decays $π^+{\rightarrow}μ^+ν_μν\barν$ and $π^+{\rightarrow}e^+ν_{e}ν\barν$ are allowed in the Standard Model but highly suppressed. These decays were searched for using data from the PIENU experiment. A first result for $Γ(π^+{\rightarrow}μ^+ν_μν\barν)/Γ(π^+{\rightarrow}μ^+ν_μ)<8.6{\times}10^{-6}$, and an improved measurement $Γ(π^+{\rightarrow
Qiunan Zhang, Ingo Deppner, Nobert Herrmann, Yi Wang
The future Facility for Anti-proton and Ion Research (FAIR), currently in construction in Darmstadt, Germany, is one of the largest research projects worldwide. The Compressed Baryonic Matter (CBM) experiment is one of the main pillars at FAIR, studying the quantum chromodynamics (QCD) phase diagram at high baryon densities with unprecedented interaction rat
Zheng Xu, Ali Shafahi, Tom Goldstein
Adversarial training has proven to be effective in hardening networks against adversarial examples. However, the gained robustness is limited by network capacity and number of training samples. Consequently, to build more robust models, it is common practice to train on widened networks with more parameters. To boost robustness, we propose a conditional norm
Foyzul Hassan, Chetan Bansal, Nachiappan Nagappan, Thomas Zimmermann
Software engineers spend a substantial amount of time using Web search to accomplish software engineering tasks. Such search tasks include finding code snippets, API documentation, seeking help with debugging, etc. While debugging a bug or crash, one of the common practices of software engineers is to search for information about the associated error or exce
Comment on: "Development of the perturbation theory using polynomial solutions" J. Math. Phys. 60, 012103 (2019)
quant-phFrancisco M. Fernández
The purpose of this comment is to present the perturbation approach proposed by Maiz J. Math. Phys. 60, 012103 (2019) in a clearer way. The results of our straightforward procedure agree with those obtained by that author except for one case in which we obtain the exact result while he obtained an approximate one. In addition to it, we show that for sufficie
Shreyashi Chakdar, P. Q Hung
Motivated by the null results of the BSM searches in the post-Higgs era of the LHC, our current approach is to look for new physics shifting from theory driven search strategies to signature driven ones. One possible direction might come from investigating the long-lived particles (LLPs) present in various theoretical scenarios through the newly formed Lifet
Boris Teabe, Peterson Yuhala, Alain Tchana, Fabien Hermenier
The utilization of paging for virtual machine (VM) memory management is the root cause of memory virtualization overhead. This paper shows that paging is not necessary in the hypervisor. In fact, memory fragmentation, which explains paging utilization, is not an issue in virtualized datacenters thanks to VM memory demand patterns. Our solution Compromis, a n
The connection between Jackson and Hausdorff derivatives in the context of generalized statistical mechanics
cond-mat.stat-mechAndre A. Marinho, G. M. Viswanathan, Francisco A. Brito, C. G. Bezerra
In literature one can find many generalizations of the usual Leibniz derivative, such as Jackson derivative, Tsallis derivative and Hausdorff derivative. In this article we present a connection between Jackson derivative and recently proposed Hausdorff derivative. On one hand, the Hausdorff derivative has been previously associated with non-extensivity in sy
Tovly Deutsch, Masoud Jasbi, Stuart Shieber
Readability assessment aims to automatically classify text by the level appropriate for learning readers. Traditional approaches to this task utilize a variety of linguistically motivated features paired with simple machine learning models. More recent methods have improved performance by discarding these features and utilizing deep learning models. However,
Peter Manohar, Jalani Williams
Caches are a fundamental component of latency-sensitive computer systems. Recent work of [ASWB20] has initiated the study of delayed hits: a phenomenon in caches that occurs when the latency between the cache and backing store is much larger than the time between new requests. We present two results for the delayed hits caching model. (1) Competitive ratio l
Vsevolod Malinovskii
Dealing with compound renewal process with generally distributed jump sizes and inter-renewal intervals, we focus on the approximation for the fixed-probability level, which is the core of inverse level crossing problem. We are developing an analytical technique presented in [15]-[17] and based on Kendall's identity; this yields (see [18]) inverse Gaussi
Sabah Al-Fedaghi, Jassim Al-Fadhli
In recent years, there has been a dramatic increase in both practical and research applications of unmanned aerial vehicles (UAVs). According to the literature, there is a need in this area to develop a more refined model of UAV system architecture, in other words, a conceptual model that defines the system s structure and behavior. The existing models mostl
Peter Butler, Jerry Lin
Plurality and approval voting are two well-known voting systems with different strengths and weaknesses. In this paper we consider a new voting system we call beta(k) which allows voters to select a single first-choice candidate and approve of any other number of candidates, where k denotes the relative weight given to a first choice; this system is essentia
Olasimbo Ayodeji Arigbabu
Human activity recognition serves an important part in building continuous behavioral monitoring systems, which are deployable for visual surveillance, patient rehabilitation, gaming, and even personally inclined smart homes. This paper demonstrates our efforts to develop a collaborative decision fusion mechanism for integrating the predicted scores from mul
Mohammadreza Tavakoli, Ali Faraji, Stefan T. Mol, Gábor Kismihók
This Work in Progress Research paper departs from the recent, turbulent changes in global societies, forcing many citizens to re-skill themselves to (re)gain employment. Learners therefore need to be equipped with skills to be autonomous and strategic about their own skill development. Subsequently, high-quality, on-line, personalized educational content and
Two symmetric four-wave mixing signals generated in a medium with anomalous refractive index
physics.opticsA. S. Alvarez, A. A. C. de Almeida, S. S. Vianna
We report experimental and theoretical results of two symmetrical signals of degenerate four-wave mixing generated in rubidium vapor. Both nonlinear signals are induced by two almost copropagating laser beams, with $\vec{k}_{a}$ and $\vec{k}_{b}$ wave-vectors, and detected simultaneously in the $2\vec{k}_{a}-\vec{k}_{b}$ and $2\vec{k}_{b}-\vec{k}_{a}$ direct
Quantum high-frequency conductivity oscillations in graphene multilayers and nodal semimetals in a tilted magnetic field
cond-mat.mes-hallJuan C. Medina Pantoja, Juan Sotelo-Campos, Igor V. Kozlov
A new type of angular oscillations of the high-frequency conductivity for conductors with a band-contact line has been predicted. The effect is caused by groups of charge carriers near the self-intersection points of the Fermi surface, where the electron energy spectrum is near-linear and can be described by anisotropic Dirac cone model. The amplitude of the
Davood Momeni Pakdehi, Philip Schädlich, T. T. Nhung Nguyen, Alexei A. Zakharov
Generally, it is supposed that the Fermi level in epitaxial graphene is controlled by two effects: p-type polarization doping induced by the bulk of the hexagonal SiC(0001) substrate and overcompensation by donor-like states related to the buffer layer. In this work, we evidence that this effect is also related to the specific underlying SiC terrace. We fabr
Plasmonic antenna coupling to hyperbolic phonon-polaritons for sensitive and fast mid-infrared photodetection with graphene
cond-mat.mes-hallSebastián Castilla, Ioannis Vangelidis, Varun-Varma Pusapati, Jordan Goldstein
Integrating and manipulating the nano-optoelectronic properties of Van der Waals heterostructures can enable unprecedented platforms for photodetection and sensing. The main challenge of infrared photodetectors is to funnel the light into a small nanoscale active area and efficiently convert it into an electrical signal. Here, we overcome all of those challe
G. J. Baxter, R. A. da Costa, S. N. Dorogovtsev, J. F. F. Mendes
We describe the critical behavior of weak multiplex percolation, a generalization of percolation to multiplex or interdependent networks. A node can determine its active or inactive status simply by referencing neighboring nodes. This is not the case for the more commonly studied generalization of percolation to multiplex networks, the mutually connected clu
Universities through the Eyes of Bibliographic Databases: A Retroactive Growth Comparison of Google Scholar, Scopus and Web of Science
cs.DLEnrique Orduna-Malea, Selenay Aytac, Clara Y. Tran
The purpose of this study is to ascertain the suitability of GS's url-based method as a valid approximation of universities' academic output measures, taking into account three aspects (retroactive growth, correlation, and coverage). To do this, a set of 100 Turkish universities were selected as a case study. The productivity in Web of Science (WoS),
Joshua Keneda, Dimitri Shlyakhtenko
We show that Bogoljubov actions of $\mathbb{R}$ on the free group factor $L(\mathbb{F}_{\infty})$ associated to sums of infinite multiplicity trivial and certain mixing representations are cocycle conjugate if and only if the underlying representations are conjugate.
Enrique Orduna-Malea
The main objective of this work is to analyse the contributions of Judit Bar-Ilan to the search engines studies. To do this, two complementary approaches have been carried out. First, a systematic literature review of 47 publications authored and co-authored by Judit and devoted to this topic. Second, an interdisciplinarity analysis based on the cited refere
Magnetization dynamics in proximity-coupled superconductor/ferromagnet/superconductor multilayers
cond-mat.supr-conI. A. Golovchanskiy, N. N. Abramov, V. S. Stolyarov, V. I. Chichkov
In this work, magnetization dynamics is studied in superconductor/ferromagnet/superconductor three-layered films in a wide frequency, field, and temperature ranges using the broad-band ferromagnetic resonance measurement technique. It is shown that in presence of both superconducting layers and of superconducting proximity at both superconductor/ferromagnet
Ady Mann, Pier A. Mello, Michael Revzen
We study the quantum-mechanical uncertainty relation originating from the successive measurement of two observables $\hat{A}$ and $\hat{B}$, with eigenvalues $a_n$ and $b_m$, respectively, performed on the same system. We use an extension of the von Neumann model of measurement, in which two probes interact with the same system proper at two successive times
Eftychios Protopapadakis, Anastasios Doulamis, Nikolaos Doulamis, Evangelos Maltezos
A combinatory approach of two well-known fields: deep learning and semi supervised learning is presented, to tackle the land cover identification problem. The proposed methodology demonstrates the impact on the performance of deep learning models, when SSL approaches are used as performance functions during training. Obtained results, at pixel level segmenta
Derek Xiao, Linfang Wang, Richard D. Wesel
In this paper, the Dynamic-Assignment Blahut-Arimoto (DAB) algorithm identifies finite-support probability mass functions (PMFs) with small cardinality that achieve capacity for amplitude-constrained (AC) Additive White Gaussian Noise (AWGN) Channels, or approach capacity to within less than 1% for power-constrained (PC) AWGN Channels. While a continuous Gau
Charles F. Manski, Aleksey Tetenov
As the COVID-19 pandemic progresses, researchers are reporting findings of randomized trials comparing standard care with care augmented by experimental drugs. The trials have small sample sizes, so estimates of treatment effects are imprecise. Seeing imprecision, clinicians reading research articles may find it difficult to decide when to treat patients wit
Hemant Mehta, Paul Harvey, Omer Rana, Rajkumar Buyya
Containers are becoming a popular workload deployment mechanism in modern distributed systems. However, there are limited software-based methods (hardware-based methods are expensive requiring hardware level changes) for obtaining the power consumed by containers for facilitating power-aware container scheduling, an essential activity for efficient managemen
Mohammadrezar Tavakoli, Maliheh Izadi, Abbas Heydarnoori
Community Question Answering platforms such as Stack Overflow help a wide range of users solve their challenges online. As the popularity of these communities has grown over the years, both the number of members and posts have escalated. Also, due to the diverse backgrounds, skills, expertise, and viewpoints of users, each question may obtain more than one a
Or Ordentlich, Oded Regev, Barak Weiss
We obtain new upper bounds on the minimal density of lattice coverings of Euclidean space by dilates of a convex body K. We also obtain bounds on the probability (with respect to the natural Haar-Siegel measure on the space of lattices) that a randomly chosen lattice L satisfies that L+K is all of space. As a step in the proof, we utilize and strengthen resu
G. Besse, V. de la Mota, E. Bonnet, P. Eudes
Static and dynamical aspects of nuclear systems are described through an extended time-dependent mean-field approach. The foundations of the formalism are presented, with highlights on the estimation of average values and their corresponding dispersions. In contrast to semiclassical transport models, the particular interest of this description lies on its in
Statistical Mechanical Analysis of the Electromechanical Coupling in an Electrically-Responsive Polymer Chain
cond-mat.softMatthew Grasinger, Kaushik Dayal
Polymeric materials that couple deformation and electrostatics have the potential for use in soft sensors and actuators with potential applications ranging from robotic, biomedical, energy, aerospace and automotive technologies. In contrast to the mechanics of polymers that has been studied using statistical mechanics approaches for decades, the coupled resp
Javier Bracho, Luis Montejano
The complex conjecture of Stefan Banach states that if V is a Banach space over the complex numbers where for some n, 1<n<dim(V), all of its n-dimensional subspaces are isometric, then V is a Hilbert space. Mikhail Gromov proved it for n even in 1967. Here, we prove it for n congruent to 1 mod 4.
Siddharth Arora, James W. Taylor, Ho-Yin Mak
We study the estimation of the probability distribution of individual patient waiting times in an emergency department (ED). Our feature-rich modelling allows for dynamic updating and refinement of waiting time estimates as patient- and ED-specific information (e.g., patient condition, ED congestion levels) is revealed during the waiting process. Aspects rel
Qian-Qian Yuan, Zhaopeng Guo, Zhi-Qiang Shi, Hui Zhao
Two-dimensional (2D) ferromagnetic materials have been exhibiting promising potential in applications, such as spintronics devices. To grow epitaxial magnetic films on silicon substrate, in the single-layer limit, is practically important but challenging. In this study, we realized the epitaxial growth of MnSn monolayer on Si(111) substrate, with an atomical
G. Proto, G. Aielli, E. Alunno Camelia, P. Camarri
The ATLAS RPC standard mixture, mainly based on C$_{2}$H$_{2}$F$_{4}$, has a high Global Warming Potential (GWP) and therefore the search for RPC eco friendly gases is mandatory. In this work we present the results on the detector performances in terms of efficiency, prompt and ionic charge, with different gas mixtures.
Kasey Wagoner, Richard Soden
A typical introductory treatment of electromagnetism culminates with the investigation of Maxwell's equations, showing the beautiful connection between the concepts covered in the many prior weeks. The lab described here is an experimental counterpart, providing a way to measure the connection between electricity, magnetism, and the speed of light. This
Buşra Karadeniz, Hussein Mourtada, Camille Plénat, Meral Tosun
We consider the question whether one can construct an embedded resolution of singularities of a singular variety $X\subset \textbf{A}^n$ from the data of the irreducible components of the spaces of jets (of $X$) centered at the singular locus of $X.$ We show that the answer is no in general and that it is yes for some birational models of rational triple sur
Wireless Power Transfer Under Kullback-Leibler Distribution Uncertainty: A Mathematical Framework
cs.ITIoannis Krikidis
In this letter, we study the performance of a wireless power transfer system under energy harvesting distribution uncertainty. The uncertainty captures practical nonidealities of the rectification process and is modelled as the maximum Kullback-Leibler distance of the actual distribution from a nominal distribution. The case where symmetrized divergence is c
Ander Wilson, Jessica Tryner, Christian L'Orange, John Volckens
In many applications there is interest in estimating the relation between a predictor and an outcome when the relation is known to be monotone or otherwise constrained due to the physical processes involved. We consider one such application--inferring time-resolved aerosol concentration from a low-cost differential pressure sensor. The objective is to estima
Ashish Kumar, Manoj K. Harbola
Most of the density-to-potential inversion methods developed over the years follow a general algorithm $ v_{xc}^{i+1}(\textbf{r}) = v_{xc}^{i}(\textbf{r}) + Δv_{xc}(\textbf{r})$, where $Δv_{xc}(\textbf{r}) = \frac{δS[ρ]}{δρ(\textbf{r})} \Big |_{ ρ_i(\textbf{r})} - \frac{δS[ρ]}{δρ(\textbf{r})}\Big|_{ ρ_0(\textbf{r})}$ and $S[ρ]$ is an appropriately chosen den
Mukremin Kilic, P. Bergeron, Alekzander Kosakowski, Warren R. Brown
We present follow-up spectroscopy of 711 white dwarfs within 100 pc, and present a detailed model atmosphere analysis of the 100 pc white dwarf sample in the SDSS footprint. Our spectroscopic follow-up is complete for 83% of the white dwarfs hotter than 6000 K, where the atmospheric composition can be constrained reliably. We identify 1508 DA white dwarfs wi
Francisco Castillo-Zunino, Pinar Keskinocak
The multiple knapsack problem with grouped items aims to maximize rewards by assigning groups of items among multiple knapsacks, considering knapsack capacities. Either all items in a group are assigned or none at all. We propose algorithms which guarantee that rewards are not less than the optimal solution, with a bound on exceeded knapsack capacities. To o
On Arnold-Villasenor Conjectures for Characterizing Exponential Distribution Based on Sample of Size Three
math.PRGeorge Yanev
Arnold and Villasenor (2013) obtain a series of characterizations of the exponential distribution based on random samples of size two. These results were already applied in constructing goodness-of-fit tests. Extending the techniques from Arnold and Villasenor (2013), we prove some of the conjectures for samples of size three. An example with simulated data
Federico Re
We push ahead the idea developed in [24], that some fraction of the dark matter and the dark energy can be explained as a relativistic effect. The inhomogeneity matter generates gravitational distortions, which are general relativistically retarded. These combine in a magnification effect since the past matter density, which generated the distortion we feel
Basins of attraction and critical curves for Newton-type methods in a phase equilibrium problem
math.NAGustavo Mendes Platt, Fran Sérgio Lobato, Gustavo Barbosa Libotte, Francisco Duarte Moura Neto
Many engineering problems are described by systems of nonlinear equations, which may exhibit multiple solutions, in a challenging situation for root-finding algorithms. The existence of several solutions may give rise to complex basins of attraction for the solutions in the algorithms, with severe influence in their convergence behavior. In this work, we exp
Sleiman Safaoui, Lars Lindemann, Dimos V Dimarogonas, Iman Shames
We present a general framework for risk semantics on Signal Temporal Logic (STL) specifications for stochastic dynamical systems using axiomatic risk theory. We show that under our recursive risk semantics, risk constraints on STL formulas can be expressed in terms of risk constraints on atomic predicates. We then show how this allows a (stochastic) STL risk
Stefan Ehbauer, Aleksandr Grishkov, Dmitry Logachev
We consider Anderson t-motives $M$ of dimension 2 and rank 4 defined by some simple explicit equations parameterized by $2\times2$ matrices. We use methods of explicit calculation of $h^1(M)$ -- the dimension of their cohomology group $H^1(M)$ ( = the dimension of the lattice of their dual t-motive $M'$) developed in our earlier paper. We calculate $h^1(
Livia Corsi, Riccardo Montalto, Michela Procesi
We prove the existence of almost-periodic solutions for quasi-linear perturbations of the Airy equation. This is the first result about the existence of this type of solutions for a quasi-linear PDE. The solutions turn out to be analytic in time and space. To prove our result we use a Craig-Wayne approach combined with a KAM reducibility scheme and pseudo-di
Richard T Hammond
Dipole fields are common in electromagnetism and may be viewed as the result of a positive and negative charge (or pole) which are close together. A dipole field in gravity is not expected to exist because negative mass has never been observed. However, an exact solution to the gravitational field equations with torsion is presented that does correspond to a
Gustavo Mendes Platt, Gustavo Barbosa Libotte, Francisco Duarte Moura Neto, Douglas Alves Goulart
In this work we propose a geometric view of the azeotropy problem, using some simplified models. We demonstrate that the occurrence of azeotropes in binary mixtures can be viewed-geometrically-as the intersection of curves in the plane (for some models, these curves are parabolas). Furthermore, the idea of functions from the plane to the plane is used to hel
Mark S. Ashbaugh, Derek Kielty
We prove sharp lower bounds on the spectral gap of 1-dimensional Schrödinger operators with Robin boundary conditions for each value of the Robin parameter. In particular, our lower bounds apply to single-well potentials with a centered transition point. This result extends work of Cheng et al. and Horváth in the Neumann and Dirichlet endpoint cases to the i
Eleftherios Kastis, Stephen Power
The parabolic algebra A_p is the weakly closed algebra on L^2(R) generated by the unitary semigroup of right translations and the unitary semigroup of multiplication by the analytic exponential functions e^{iλx}, λ\geq 0. This algebra is reflexive with an invariant subspace lattice, Lat A_p, which is naturally homeomorphic to the unit disc (Katavolos and Pow
Linearity and rate capability measurements of RPC with semi-insulating crystalline electrodes operating in avalanche mode
physics.ins-detA. Rocchi, R. Cardarelli, B. Liberti, G. Aielli
The intrinsic rate capability and the ageing properties of the Resistive Plate Chambers are closely related to the electrodes material and to the front-end electronics threshold. The development of a low noise pre-amplifier led us to improve the intrinsic rate capability of High Pressure Laminate (bakelite) up to $\sim10\;kHz/cm^2$, nevertheless the effectiv
Yue Zhang, David Defazio, Arti Ramesh
In recent years, considerable progress has been made on improving the interpretability of machine learning models. This is essential, as complex deep learning models with millions of parameters produce state of the art results, but it can be nearly impossible to explain their predictions. While various explainability techniques have achieved impressive resul
Jianqiang Wan, Yang Liu, Donglai Wei, Xiang Bai
Image segmentation is a fundamental vision task and a crucial step for many applications. In this paper, we propose a fast image segmentation method based on a novel super boundary-to-pixel direction (super-BPD) and a customized segmentation algorithm with super-BPD. Precisely, we define BPD on each pixel as a two-dimensional unit vector pointing from its ne
A geometric construction of integrable Hamiltonian hierarchies associated with the classical affine W-algebras
math.QAShigenori Nakatsuka
A class of classical affine W-algebras are shown to be isomorphic as differential algebras to the coordinate rings of double coset spaces of certain prounipotent proalgebraic groups. As an application, integrable Hamiltonian hierarchies associated with them are constructed geometrically, generalizing the corresponding result of Feigin-Frenkel and Enriquez-Fr
An Alternative Perspective on Copositive and Convex Relaxations of Nonconvex Quadratic Programs
math.OCE. Alper Yildirim
We study convex relaxations of nonconvex quadratic programs. We identify a family of so-called feasibility preserving convex relaxations, which includes the well-known copositive and doubly nonnegative relaxations, with the property that the convex relaxation is feasible if and only if the nonconvex quadratic program is feasible. We observe that each convex
Bruno Nachtergaele, Simone Warzel, Amanda Young
We identify the the ground-state of a truncated version of Haldane's pseudo-potential Hamiltonian in a thin cylinder geometry as being composed of exponentially many fragmented matrix product states. These states are constructed by lattice tilings and their properties are discussed. We also report on a proof of a spectral gap, which implies the incompres
Radiative Correction to the Casimir Energy for Lorentz-violating Scalar Field in d+1 Dimensions
hep-thM. A. Valuyan
The renormalization program in every renormalized theory should be run consistently with the type of boundary condition imposed on quantum fields. To maintain this consistency, the counterterms usually appear in the position-dependent form. In the present study, using such counterterms, we calculated the radiative correction to the Casimir energy for massive
Henry N. Chapman, Saša Bajt
Thick diffractive optical elements offer a promising way to achieve focusing or imaging at a resolution approaching 1 nm for X-ray wavelengths shorter than about 0.1 nm. Efficient focusing requires that these are fabricated with structures that vary in period and orientation so that rays obey Bragg's law over the entire lens aperture and give rise to con
Xiaole Su, Hongwei Sun, Yusheng Wang
In this paper, we introduce quasi-convex subsets in Alxandrov spaces with lower curvature bound, which include not only all closed convex subsets without boundary but also all extremal subsets. Moreover, we explore several essential properties of such kind of subsets including a generalized Liberman theorem. It turns out that the quasi-convex subset is a nic
Luigi Barletti, Claudia Negulescu
We present a formal derivation of a drift-diffusion model for stationary electron transport in graphene, in presence of sharp potential profiles, such as barriers and steps. Assuming the electric potential to have steep variations within a strip of vanishing width on a macroscopic scale, such strip is viewed as a quantum interface that couples the classical
J. P. Mendonça, F. A. B. F. de Moura, M. L. Lyra, G. M. A. Almeida
We study the dynamics of entanglement in a 1D coupled-cavity array, each cavity containing a two-level atom, via the Jaynes-Cummings-Hubbard (JCH) Hamiltonian in the single-excitation sector. The model features a rich variety of dynamical regimes that can be harnessed for entanglement control. The protocol is based on setting an excited atom above the ground
Lucas de Oliveira Contiero, Carlos Hoppen, Hanno Lefmann, Knut Odermann
The Fano plane is the unique linear 3-uniform hypergraph on seven vertices and seven hyperedges. It was recently proved that, for all $n \geq 8$, the balanced complete bipartite 3-uniform hypergraph on $n$ vertices, denoted by $B_n$, is the 3-uniform hypergraph on $n$ vertices with the largest number of hyperedges that does not contain a copy of the Fano pla
Stefano Fioravanti
We investigate finitary functions from $\mathbb{Z}_{pq}$ to $\mathbb{Z}_{pq}$ for two distinct prime numbers $p$ and $q$. We show that the lattice of all clones on the set $\mathbb{Z}_{pq}$ which contain the addition of $\mathbb{Z}_{pq}$ is finite. We provide an upper bound for the cardinality of this lattice through an injective function to the direct produ
Identification of an Epidemiological Model to Simulate the COVID-19 Epidemic using Robust Multi-objective Optimization and Stochastic Fractal Search
q-bio.PEGustavo Barbosa Libotte, Fran Sérgio Lobato, Gustavo Mendes Platt
Traditionally, the identification of parameters in the formulation and solution of inverse problems considers that models, variables and mathematical parameters are free of uncertainties. This aspect simplifies the estimation process, but does not consider the influence of relatively small changes in the design variables in terms of the objective function. I
Xingchu Zhang, Weilong She
In this letter, the wavelet transform is used to decompose the classical linearly polarized plane light wave into a series of discrete Morlet wavelets. It is found that the energy of the light wave can be discrete, associated with its discrete wavelet structure.It is also found that the changeable energy of a basic plane light wave packet or wave train of wa
Meena Sahai, Bhagwat Sharan
In this article, we show that if $KG$ is Lie nilpotent group algebra of a group $G$ over a field $K$ of characteristic $p>0$, then $t_{L}(KG)=k$ if and only if $t^{L}(KG)=k$, for $k\in\{5p-3, 6p-4\}$, where $t_{L}(KG)$ and $t^{L}(KG)$ are the lower and the upper Lie nilpotency indices of $KG$, respectively.
Wei Xiao, Christos G. Cassandras, Calin Belta
We address the problem of optimally controlling Connected and Automated Vehicles (CAVs) arriving from two multi-lane roads and merging at multiple points where the objective is to jointly minimize the travel time and energy consumption of each CAV subject to speed-dependent safety constraints, as well as speed and acceleration constraints. This problem was s
Shi Tingsheng, Ian K. Duncan, Yen-Ning Chang, Michael T. Gastner
Cartograms are maps in which the areas of regions (e.g., countries or provinces) are proportional to a thematic mapping variable (e.g., population or gross domestic product). A cartogram is called contiguous if it keeps geographically adjacent regions connected. Over the past few years, several web tools have been developed for the creation of contiguous car
HyungSeon Oh
Wind energy has been integrated into the power system with the hope that it improves the energy efficiency and decreases greenhouse gas emission. However, several studies over the world imply that the result was in the opposite way that was hoped mainly because of the negative correlation between wind availability and load. Under the situation, coal power pl
Dennis J. N. J. Soemers, Éric Piette, Matthew Stephenson, Cameron Browne
Expert Iteration (ExIt) is an effective framework for learning game-playing policies from self-play. ExIt involves training a policy to mimic the search behaviour of a tree search algorithm - such as Monte-Carlo tree search - and using the trained policy to guide it. The policy and the tree search can then iteratively improve each other, through experience g
Neofytos Rodosthenous, Hongzhong Zhang
We consider risk averse investors with different levels of anxiety about asset price drawdowns. The latter is defined as the distance of the current price away from its best performance since inception. These drawdowns can increase either continuously or by jumps, and will contribute towards the investor's overall impatience when breaching the investor&#
Changchuan Yin
The ongoing global pandemic of infection disease COVID-19 caused by the 2019 novel coronavirus (SARS-COV-2, formerly 2019-nCoV) presents critical threats to public health and the economy since it was identified in China, December 2019. The genome of SARS-CoV-2 had been sequenced and structurally annotated, yet little is known of the intrinsic organization an
Rebecca Mitchell, Roger Maull, Simon Pearson, Steve Brewer
The resilience of the food supply chain is a matter of critical importance, both for national security and broader societal well bring. COVID19 has presented a test to the current system, as well as means by which to explore whether the UK's food supply chain will be resilient to future disruptions. In the face of a growing need to ensure that food suppl
Automated Delineation of Hospital Service Areas and Hospital Referral Regions by Modularity Optimization
stat.APYujie Hu, Fahui Wang, Imam Xierali
Objective. To develop an automated, data-driven, and scale-flexible method to delineate HSAs and HRRs that are up-to-date, representative of all patients, and have the optimal localization of hospital visits. Data Sources. The 2011 State Inpatient Database (SID) in Florida from the Healthcare Cost and Utilization Project (HCUP). Study Design. A network optim
Morphological and spectral study of 4FGL J1115.1-6118 in the region of the young massive stellar cluster NGC 3603
astro-ph.HEL. Saha, A. Domínguez, L. Tibaldo, S. Marchesi
We report a detailed study of an unidentified gamma-ray source located in the region of the compact stellar cluster NGC 3603. This is a star-forming region (SFR) powered by a massive cluster of OB stars. A dedicated analysis of about 10 years of data from 10 GeV - 1 TeV, provided by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope,
Positron Emission Tomography (PET) image enhancement using a gradient vector orientation based nonlinear diffusion filter (GVOF) for accurate quantitation of radioactivity concentration
eess.IVMahbubunnabi Tamal
To accurately quantify in vivo radiotracer uptake using Positron Emission Tomography (PET) is a challenging task due to low signal-to-noise ratio (SNR) and poor spatial resolution of PET camera along with the finite image sampling constraint. Furthermore, inter lesion variations of the SNR and contrast along with the variations in size of the lesion make the
A Spatio-Temporal Kernel Density Estimation Framework for Predictive Crime Hotspot Mapping and Evaluation
stat.APYujie Hu, Fahui Wang, Cecile Guin, Haojie Zhu
Predictive hotspot mapping plays a critical role in hotspot policing. Existing methods such as the popular kernel density estimation (KDE) do not consider the temporal dimension of crime. Building upon recent works in related fields, this article proposes a spatio-temporal framework for predictive hotspot mapping and evaluation. Comparing to existing work in
Georgios P. Balomenos, Yujie Hu, Jamie E. Padgett, Kyle Shelton
The mobility of residents and their access to essential services can be highly affected by transportation network closures that occur during and after coastal hazard events. Few studies have used geographic information systems coupled with infrastructure vulnerability models to explore how spatial accessibility to goods and services shifts after a hurricane.
Camila Dias dos Reis Barros, Janaina Cardozo Rocha, Ivan Napoleão Bastos, José Antônio da Cunha Ponciano Gomes
Micromovements that occur in the joint between dental prostheses and implants can lead to wear-induced degradation. This process can be enhanced by corrosion in the oral environment influenced by the presence of solutions containing fluoride. Moreover, the eventual galvanic interactions between NiCr and Ti alloys can accelerate the wear-corrosion process. In
Yujie Hu, Joni Downs
Place-based accessibility measures, such as the gravity-based model, are widely applied to study the spatial accessibility of workers to job opportunities in cities. However, gravity-based measures often suffer from three main limitations: (1) they are sensitive to the spatial configuration and scale of the units of analysis, which are not specifically desig
Hyung Park, Eva Petkova, Thaddeus Tarpey, R. Todd Ogden
Sparse additive modeling is a class of effective methods for performing high-dimensional nonparametric regression. This paper develops a sparse additive model focused on estimation of treatment effect-modification with simultaneous treatment effect-modifier selection. We propose a version of the sparse additive model uniquely constrained to estimate the inte
Hyung Park, Eva Petkova, Thaddeus Tarpey, R. Todd Ogden
Dimension reduction lies at the heart of many statistical methods. In regression, dimension reduction has been linked to the notion of sufficiency whereby the relation of the response to a set of predictors is explained by a lower dimensional subspace in the predictor space. In this paper, we consider the notion of a dimension reduction in regression on subs