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In this paper, we propose a parallel-in-time algorithm for approximately solving parabolic equations. In particular, we apply the $k$-step backward differentiation formula, and then develop an iterative solver by using the waveform…

Numerical Analysis · Mathematics 2021-06-04 Shuonan Wu , Zhi Zhou

In this paper, we consider the asymptotic behavior of solutions to the wave equation with space-dependent damping in an exterior domain. We prove that when the damping is effective, the solution is approximated by that of the corresponding…

Analysis of PDEs · Mathematics 2016-10-11 Motohiro Sobajima , Yuta Wakasugi

The distribution function of relaxation times in disordered dielectrics has been calculated in the random field theory framework. For this purpose, we first consider the dynamics of single two-orientable impurity electric dipole in a random…

Materials Science · Physics 2007-05-23 V. A. Stephanovich , M. D. Glinchuk , B. Hilczer , L. Jastrabik

The reaction-diffusion equation is one of the cornerstones equations in applied science and engineering. In the present study, a deep neural network has been trained in order to predict the solution of the equation with different…

Machine Learning · Computer Science 2019-12-12 Amin Karimi Monsefi , Rana Bakhtiyarzade

We study the systematic numerical approximation of a class of Allen-Cahn type problems modeling the motion of phase interfaces. The common feature of these models is an underlying gradient flow structure which gives rise to a decay of an…

Numerical Analysis · Mathematics 2017-03-09 Anke Böttcher , Herbert Egger

The dynamics of the electrons for a molecule in solution is coupled to the dynamics of its polarizable environment, i.e., the solvent. To theoretically investigate such electronic dynamics, we have recently developed equations of motion…

Chemical Physics · Physics 2017-02-16 Silvio Pipolo , Stefano Corni , Roberto Cammi

This paper is concerned with the connection between the properties of dielectric relaxation and ac (alternating-current) conduction in disordered dielectrics. The discussion is divided between the classical linear-response theory and a…

Disordered Systems and Neural Networks · Physics 2009-11-13 Alexander V. Milovanov , Jens Juul Rasmussen , Kristoffer Rypdal

Enabling control over a spontaneous dynamic process is a very complicated task in practice because of its statistical nature, and electro-optic (E-O) relaxation dynamic in a nematic liquid crystal (NLC) system is not an exception.…

Optics · Physics 2019-01-23 Suman Kalyan Manna , Laurent Dupont , Guoqiang Li

We consider a decision maker who must choose an action in order to maximize a reward function that depends also on an unknown parameter {\Theta}. The decision maker can delay taking the action in order to experiment and gather additional…

Machine Learning · Statistics 2021-06-22 Victor F. Araman , Rene Caldentey

This paper is concerned with the numerical solution of porous-media flow and transport problems , i. e. heterogeneous, advection-diffusion problems. Its aim is to investigate numerical schemes for these problems in which different time…

Numerical Analysis · Mathematics 2016-05-20 Thi-Thao-Phuong Hoang , Caroline Japhet , Michel Kern , Jean E. Roberts

We present an investigation into diffusion models for molecular generation, with the aim of better understanding how their predictions compare to the results of physics-based calculations. The investigation into these models is driven by…

We consider an initial-boundary value problem for $\partial_tu-\partial_t^{-\alpha}\nabla^2u=f(t)$, that is, for a fractional diffusion ($-1<\alpha<0$) or wave ($0<\alpha<1$) equation. A numerical solution is found by applying a…

Numerical Analysis · Mathematics 2016-02-02 Kassem Mustapha , William McLean

Approximations of the Dirac delta distribution are commonly used to create sequences of smooth functions approximating nonsmooth (generalized) functions, via convolution. In this work, we show a priori rates of convergence of this…

Numerical Analysis · Mathematics 2021-11-18 Luca Heltai , Wenyu Lei

Different relaxation approximations to partial differential equations, including conservation laws, Hamilton-Jacobi equations, convection-diffusion problems, gas dynamics problems, have been recently proposed. The present paper focuses onto…

Numerical Analysis · Mathematics 2007-05-23 Fausto Cavalli , Matteo Semplice

We investigate numerical behaviour of a convection diffusion equation with random coefficients by approximating statistical moments of the solution. Stochastic Galerkin approach, turning the original stochastic problem to a system of…

Numerical Analysis · Mathematics 2021-10-19 Pelin Çiloğlu , Hamdullah Yücel

We discuss the relaxation kinetics of a one-dimensional dimer adsorption model as recently proposed for the binding of biological dimers like kinesin on microtubules. The non-equilibrium dynamics shows several regimes: irreversible…

Soft Condensed Matter · Physics 2007-05-23 Andrej Vilfan , Erwin Frey , Franz Schwabl

The energy relaxation in the spin-polarized disordered electron systems is studied in the diffusive regime. We derived the quantum kinetic equation in which the kernel of electron-electron collision integral explicitly depends on the…

Mesoscale and Nanoscale Physics · Physics 2009-04-05 N. M. Chtchelkatchev , I. S. Burmistrov

In this paper, a recently developed numerical technique [{\em Tuncer E and Guba{\'n}ski S M, IEEE Trans Diel El Insul {\bf 8}(3)(2001) 310-320}] is applied to poly(propylene glycol) complex dielectric data to extract more information about…

Soft Condensed Matter · Physics 2007-05-23 Enis Tuncer , Marizio Furlani , Bengt-Erik Mellander

A physical-mathematical approach to anomalous diffusion may be based on generalized diffusion equations (containing derivatives of fractional order in space or/and time) and related random walk models. The fundamental solution (for the…

Statistical Mechanics · Physics 2007-09-25 Rudolf Gorenflo , Francesco Mainardi , Daniele Moretti , Gianni Pagnini , Paolo Paradisi

Problems with localized nonhomogeneous material properties present well-known challenges for numerical simulations. In particular, such problems may feature large differences in length scales, causing difficulties with meshing and…

Numerical Analysis · Mathematics 2021-11-23 Alex Viguerie , Silvia Bertoluzza , Alessandro Veneziani , Ferdinando Auricchio