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Related papers: Time-fractional diffusion of distributed order

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We provide explicit classical solutions and stochastic analogues for distributed-order space-time fractional diffusion equations on bounded domains with zero exterior boundary conditions. We also show that our results still hold when the…

Analysis of PDEs · Mathematics 2022-10-11 Ngartelbaye Guerngar , James McCormick

This paper establishes explicit solutions for fractional diffusion problems on bounded domains. It also gives stochastic solutions, in terms of Markov processes time-changed by an inverse stable subordinator whose index equals the order of…

Probability · Mathematics 2016-04-22 Boris Baeumer , Tomasz Luks , Mark M. Meerschaert

Continuous time random walks are non-Markovian stochastic processes, which are only partly characterized by single-time probability distributions. We derive a closed evolution equation for joint two-point probability density functions of a…

Statistical Mechanics · Physics 2009-11-13 A. Baule , R. Friedrich

This paper is concerned with the fractional evolution equation with a discrete distribution of Caputo time-derivatives such that the largest and the smallest orders, $\alpha$ and $\alpha_m$, satisfy the conditions $1<\alpha\le 2$ and…

Analysis of PDEs · Mathematics 2018-01-11 Emilia Bazhlekova , Ivan Bazhlekov

Based on the non-Markov diffusion equation taking into account the spatial fractality and modeling for the generalized coefficient of particle diffusion…

Statistical Mechanics · Physics 2024-06-19 P. Kostrobij , M. Tokarchuk , B. Markovych , I. Ryzha

We develop a fully discrete scheme for time-fractional diffusion equations by using a finite difference method in time and a finite element method in space. The fractional derivatives are used in Caputo sense. Stability and error estimates…

Analysis of PDEs · Mathematics 2019-08-05 Moulay Rchid Sidi Ammi , Ismail Jamiai , Delfim F. M. Torres

In this work, we explore both the ordinary $q$-Gaussian distribution and a new one defined here, determining both their mean and variance, and we use them to construct solutions of the $q$-deformed diffusion differential equation. This…

Statistical Mechanics · Physics 2025-09-17 Won Sang Chung , L. M. Nieto , Soroush Zare , Hassan Hassanabadi

In this paper we construct a new difference analog of the Caputo fractional derivative (called the $L2$-$1_\sigma$ formula). The basic properties of this difference operator are investigated and on its basis some difference schemes…

Numerical Analysis · Mathematics 2014-10-20 A. A. Alikhanov

This paper for the first time addresses the concepts of regional gradient observability for the Riemann-Liouville time fractional order diffusion system in an interested subregion of the whole domain without the knowledge of the initial…

Optimization and Control · Mathematics 2016-08-09 Fudong Ge , YangQuan Chen , Chunhai Kou

This paper investigates quenching solutions of an one-dimensional, two-sided Riemann-Liouville fractional order convection-diffusion problem. Fractional order spatial derivatives are discretized using weighted averaging approximations in…

Analysis of PDEs · Mathematics 2025-03-06 Rumin Dong , Lin Zhu , Qin Sheng , Bingxin Zhao

Super-diffusion, characterized by a spreading rate $t^{1/\alpha}$ of the probability density function $p(x,t) = t^{-1/\alpha} p \left( t^{-1/\alpha} x , 1 \right)$, where $t$ is time, may be modeled by space-fractional diffusion equations…

Statistical Mechanics · Physics 2019-02-20 James F. Kelly , Mark M. Meerschaert

We study solution techniques for an evolution equation involving second order derivative in time and the spectral fractional powers, of order $s \in (0,1)$, of symmetric, coercive, linear, elliptic, second-order operators in bounded domains…

Numerical Analysis · Mathematics 2018-06-18 Lehel Banjai , Enrique Otarola

We consider a class of numerical approximations to the Caputo fractional derivative. Our assumptions permit the use of nonuniform time steps, such as is appropriate for accurately resolving the behavior of a solution whose derivatives are…

Numerical Analysis · Mathematics 2020-12-23 Hong-lin Liao , William McLean , Jiwei Zhang

We present and analyze a space-time Petrov-Galerkin finite element method for a time-fractional diffusion equation involving a Riemann-Liouville fractional derivative of order $\alpha\in(0,1)$ in time and zero initial data. We derive a…

Numerical Analysis · Mathematics 2017-07-26 Beiping Duan , Bangti Jin , Raytcho Lazarov , Joseph Pasciak , Zhi Zhou

This paper deals with the distributed order time-fractional diffusion equations with non-homogeneous Dirichlet (Nuemann) boundary condition. We first prove the wellposedness of the weak solution to the initial boundary value problem for the…

Analysis of PDEs · Mathematics 2018-08-13 Zhiyuan Li , Kenichi Fujishiro , Gongsheng Li

We consider an evolution equation with the regularized fractional derivative of an order $\alpha \in (0,1)$ with respect to the time variable, and a uniformly elliptic operator with variable coefficients acting in the spatial variables.…

Analysis of PDEs · Mathematics 2012-06-26 Samuil D. Eidelman , Anatoly N. Kochubei

This paper is devoted to an in deep investigation of the first fundamental solution to the linear multi-dimensional space-time-fractional diffusion-wave equation. This equation is obtained from the diffusion equation by replacing the first…

Analysis of PDEs · Mathematics 2021-03-12 Yuri Luchko

We present a general framework for the rigorous numerical analysis of time-fractional nonlinear parabolic partial differential equations, with a fractional derivative of order $\alpha\in(0,1)$ in time. The framework relies on three…

Numerical Analysis · Mathematics 2017-12-05 Bangti Jin , Buyang Li , Zhi Zhou

We study solution techniques for parabolic equations with fractional diffusion and Caputo fractional time derivative, the latter being discretized and analyzed in a general Hilbert space setting. The spatial fractional diffusion is realized…

Numerical Analysis · Mathematics 2015-03-05 Ricardo H. Nochetto , Enrique Otarola , Abner J. Salgado

In this paper, we develop a numerical algorithm for an inverse problem on determining fractional orders of time derivatives simultaneously in a coupled subdiffusion system. Following the theoretical uniqueness, we reformulate the order…

Numerical Analysis · Mathematics 2025-08-19 Yikan Liu