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Related papers: Fractional Diffusion based on Riemann-Liouville Fr…

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The Riemann-Liouville fractional integrals and derivatives are generalized for cases when fractional exponent $d$ are functions of space and times coordinates (i.e. $d=d({\bf r}(t),t)$).

Classical Analysis and ODEs · Mathematics 2007-05-23 L. Ya. Kobelev

In this paper, we consider forward and inverse problems for subdiffusion equations with time-dependent coefficients. The fractional derivative is taken in the sense of Riemann-Liouville. Using the classical Fourier method, the theorem of…

Analysis of PDEs · Mathematics 2023-05-02 Ravshan Ashurov , Yusuf Fayziev , Muattar Khudoykulova

In the present article, we study the diffusion equations with fractional time derivatives. The aim of this paper is to investigate the best possible regularity for the initial value/boundary value problems with non-homogeneous Dirichlet…

Analysis of PDEs · Mathematics 2015-01-08 Kenichi Fujishiro

We examine initial-boundary value problems for diffusion equations with distributed order time-fractional derivatives. We prove existence and uniqueness results for the weak solution to these systems, together with its continuous dependency…

Analysis of PDEs · Mathematics 2017-09-21 Zhiyuan Li , Yavar Kian , Eric Soccorsi

An initial-boundary value problem for a time-fractional subdiffusion equation with the Riemann-Liouville derivatives on N-dimensional torus is considered. The uniqueness and existence of the classical solution of the posed problem are…

Analysis of PDEs · Mathematics 2021-05-18 Ravshan Ashurov , Oqila Muhiddinova

Fractional variational approach has gained much attention in recent years. There are famous fractional derivatives such as Caputo derivative, Riesz derivative and Riemann-Liouville derivative. Several versions of fractional variational…

Mathematical Physics · Physics 2010-06-28 Guo-cheng Wu

In this paper, some initial-boundary-value problems for the time-fractional diffusion equation are first considered in open bounded n-dimensional domains. In particular, the maximum principle well-known for the PDEs of elliptic and…

Analysis of PDEs · Mathematics 2012-05-08 Yuri Luchko

We study invariant solutions of a certain class of time-fractional diffusion-wave equations with variable coefficients via Lie symmetry analysis. In physics, the fractional diffusion equation describes transport dynamics that are governed…

While it is known that one can consider the Cauchy problem for evolution equations with Caputo derivatives, the situation for the initial value problems for the Riemann-Liouville derivatives is less understood. In this paper we propose new…

Analysis of PDEs · Mathematics 2022-06-28 Erkinjon Karimov , Michael Ruzhansky , Niyaz Tokmagambetov

Fractional diffusion equations replace the integer-order derivatives in space and time by their fractional-order analogues. They are used in physics to model anomalous diffusion. This paper develops strong solutions of space-time fractional…

Probability · Mathematics 2016-12-19 Zhen-Qing Chen , Mark M. Meerschaert , Erkan Nane

This work contributes to the theory of nth level fractional derivative, where $n$ is a positive integer. An equivalent representation of 2nd level fractional derivative in terms of Riemann-Liouville fractional derivative is presented. We…

Analysis of PDEs · Mathematics 2025-06-17 Asim Ilyas , Salman A. Malik , Kamran Suhaib

We introduce more general concepts of Riemann-Liouville fractional integral and derivative on time scales, of a function with respect to another function. Sufficient conditions for existence and uniqueness of solution to an initial value…

Classical Analysis and ODEs · Mathematics 2018-07-24 Kheira Mekhalfi , Delfim F. M. Torres

This paper deals with the solution of unified fractional reaction-diffusion systems. The results are obtained in compact and elegant forms in terms of Mittag-Leffler functions and generalized Mittag-Leffler functions, which are suitable for…

Classical Analysis and ODEs · Mathematics 2014-09-11 R. K. Saxena , A. M. Mathai , H. J. Haubold

It is well-known that one-dimensional time fractional diffusion-wave equations with variable coefficients can be reduced to ordinary fractional differential equations and systems of linear fractional differential equations via scaling…

Classical Analysis and ODEs · Mathematics 2019-05-07 Khongorzul Dorjgotov , Hiroyuki Ochiai , Uuganbayar Zunderiya

This work studies exact solvability of a class of fractional reaction-diffusion equation with the Riemann-Liouville fractional derivatives on the half-line in terms of the similarity solutions. We derived the conditions for the equation to…

Statistical Mechanics · Physics 2024-03-12 C. -L. Ho

This paper deals with the investigation of the solution of an unified fractional reaction-diffusion equation associated with the Caputo derivative as the time-derivative and Riesz-Feller fractional derivative as the space-derivative. The…

Probability · Mathematics 2008-09-16 H. J. Haubold , A. M. Mathai , R. K. Saxena

In this paper, we study an inverse problem for identifying the initial value in a space-time fractional diffusion equation from the final time data. We show the identifiability of this inverse problem by proving the existence of its unique…

Analysis of PDEs · Mathematics 2024-12-10 Mohamed BenSalah , Salih Tatar

We consider boundary value problems with Riemann-Liouville fractional derivatives of order $s\in (1, 2)$ with non-constant diffusion and reaction coefficients. A variational formulation is derived and analyzed leading to the well-posedness…

Numerical Analysis · Mathematics 2025-09-03 Ruben Aylwin , Göksu Oruc , Karsten Urban

There has been considerable recent study in "sub-diffusion" models that replace the standard parabolic equation model by a one with a fractional derivative in the time variable. There are many ways to look at this newer approach and one…

Analysis of PDEs · Mathematics 2019-04-08 William Rundell , Zhidong Zhang

In this paper, we discuss initial-boundary value problems for linear diffusion equation with multiple time-fractional derivatives. By means of the Mittag-Leffler function and the eigenfunction expansion, we reduce the problem to an integral…

Analysis of PDEs · Mathematics 2013-11-12 Zhiyuan Li , Masahiro Yamamoto