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In this work, we present a comprehensive framework for approximating the weakly singular power-law kernel $t^{\alpha-1}$ of fractional integral and differential operators, where $\alpha \in (0,1)$ and $t \in [\delta,T]$ with…

Numerical Analysis · Mathematics 2025-08-29 Renu Chaudhary , Kai Diethelm , Afshin Farhadi , Fred A. Fuchs

A fast two-level linearized scheme with unequal time-steps is constructed and analyzed for an initial-boundary-value problem of semilinear subdiffusion equations. The two-level fast L1 formula of the Caputo derivative is derived based on…

Numerical Analysis · Mathematics 2020-12-23 Hong-lin Liao , Yonggui Yan , Jiwei Zhang

We investigate a second-order accurate time-stepping scheme for solving a time-fractional diffusion equation with a Caputo derivative of order~$\alpha \in (0,1)$. The basic idea of our scheme is based on local integration followed by linear…

Numerical Analysis · Mathematics 2024-07-10 Kassem Mustapha , William McLean , Josef Dick

In this paper, we consider a fast and second-order implicit difference method for approximation of a class of time-space fractional variable coefficients advection-diffusion equation. To begin with, we construct an implicit difference…

Numerical Analysis · Mathematics 2019-07-12 Yong-Liang Zhao , Ting-Zhu Huang , Xian-Ming Gu , Wei-Hua Luo

The solution of a Caputo time fractional diffusion equation of order $0<\alpha<1$ is expressed in terms of the solution of a corresponding integer order diffusion equation. We demonstrate a linear time mapping between these solutions that…

Computational Physics · Physics 2015-04-28 Peter W. Stokes , Bronson Philippa , Wayne Read , Ronald D. White

In this paper, the time fractional reaction-diffusion equations with the Caputo fractional derivative are solved by using the classical $L1$-formula and the finite volume element (FVE) methods on triangular grids. The existence and…

Numerical Analysis · Mathematics 2021-02-01 Zhichao Fang , Jie Zhao , Hong Li , Yang Liu

We introduce a method which provides accurate numerical solutions to fractional-in-time partial differential equations posed on $[0,T] \times \Omega$ with $\Omega \subset \mathbb{R}^d$ without the excessive memory requirements associated…

Numerical Analysis · Mathematics 2023-10-12 Timon S. Gutleb , José A. Carrillo

We present an exponentially convergent numerical method to approximate the solution of the Cauchy problem for the inhomogeneous fractional differential equation with an unbounded operator coefficient and Caputo fractional derivative in…

Numerical Analysis · Mathematics 2025-04-08 Dmytro Sytnyk , Barbara Wohlmuth

We study a fully discrete finite element method for variable-order time-fractional diffusion equations with a time-dependent variable order. Optimal convergence estimates are proved with the first-order accuracy in time (and second order…

Numerical Analysis · Mathematics 2019-05-15 Xiangcheng Zheng , Fanhai Zeng , Hong Wang

Open-vocabulary semantic segmentation (OVSS) aims to segment objects from arbitrary text categories without requiring densely annotated datasets. Although contrastive learning based models enable zero-shot segmentation, they often lose fine…

Computer Vision and Pattern Recognition · Computer Science 2026-04-30 Huy Che , Vinh-Tiep Nguyen

The scalar auxiliary variable (SAV) approach is a very popular and efficient method to simulate various phase field models. To save the computational cost, a new SAV approach is given by introducing a new variable $\theta$. The new SAV…

Numerical Analysis · Mathematics 2021-10-04 Zhengguang Liu , Xiaoli Li

We consider the initial/boundary value problem for the fractional diffusion and diffusion-wave equations involving a Caputo fractional derivative in time. We develop two "simple" fully discrete schemes based on the Galerkin finite element…

Numerical Analysis · Mathematics 2015-10-13 Bangti Jin , Raytcho Lazarov , Zhi Zhou

In this work, we explore a time-fractional diffusion equation of order $\alpha \in (0,1)$ with a stochastic diffusivity parameter. We focus on efficient estimation of the expected values (considered as an infinite dimensional integral on…

Numerical Analysis · Mathematics 2024-09-04 Josef Dick , Hecong Gao , William McLean , Kassem Mustapha

In this work, a new collocation approach using a combination of a wavelet operational matrix method and the exponential spline interpolation is proposed to solve the time-fractional convection-diffusion equation with variable coefficients.…

Numerical Analysis · Mathematics 2016-09-27 Xiaogang Zhu , Yufeng Nie

The present paper deals with the numerical solution of time-fractional advection-diffusion equations involving the Caputo derivative with source term by means of an unconditionally stable implicit finite difference method on quasi-uniform…

Numerical Analysis · Mathematics 2018-02-14 Riccardo Fazio , Alessandra Jannelli

In this work, we propose an exponentially convergent numerical method for the Caputo fractional propagator $S_\alpha(t)$ and the associated mild solution of the Cauchy problem with time-independent sectorial operator coefficient $A$ and…

Numerical Analysis · Mathematics 2025-04-08 Dmytro Sytnyk

This study presents a novel high-order numerical method designed for solving the two-dimensional time-fractional convection-diffusion (TFCD) equation. The Caputo definition is employed to characterize the time-fractional derivative. A weak…

Numerical Analysis · Mathematics 2023-08-21 Anshima Singh , Sunil Kumar

The present paper is devoted to constructing L2 type difference analog of the Caputo fractional derivative. The fundamental features of this difference operator are studied and it is used to construct difference schemes generating…

Numerical Analysis · Mathematics 2021-02-18 Anatoly A. Alikhanov , Chengming Huang

We investigate a local modification of a variable-order fractional wave equation, which describes the propagation of diffusive wave in viscoelastic media with evolving physical property. We incorporate an equivalent formulation to prove the…

Numerical Analysis · Mathematics 2025-11-11 Jinhong Jia , Chuanting Jiang , Yiqun Li , Mengmeng Liu , Wenlin Qiu

Fractional differential equations (FDEs) are an extension of the theory of fractional calculus. However, due to the difficulty in finding analytical solutions, there have not been extensive applications of FDEs until recent decades. With…

Numerical Analysis · Mathematics 2020-07-20 Nirupama Bhattacharya , Gabriel A. Silva