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In this paper we present numerical methods - finite differences and finite elements - for solution of partial differential equation of fractional order in time for one-dimensional space. This equation describes anomalous diffusion which is…

Mathematical Physics · Physics 2007-05-23 Mariusz Ciesielski , Jacek Leszczynski

We propose an interpolation expression using the difference moment (Kolmogorov transient structural function) of the second order as the average characteristic of displacements for identifying the anomalous diffusion in complex processes…

Data Analysis, Statistics and Probability · Physics 2010-08-25 Serge F. Timashev , Yuriy S. Polyakov , Pavel I. Misurkin , Sergey G. Lakeev

This paper derives the Fokker-Planck (FP) equation for a particle moving in potential by a randomly modulated dipole. The FP equation describes the anomalous diffusion observed in the companion paper [1] and breaks the conservation of the…

Mathematical Physics · Physics 2022-05-03 S. Katagiri , Y. Matsuo , Y. Matsuoka , A. Sugamoto

The rapid advancements in machine learning have made its application to anomalous diffusion analysis both essential and inevitable. This review systematically introduces the integration of machine learning techniques for enhanced analysis…

Machine Learning · Computer Science 2025-04-01 Wenjie Cai , Yi Hu , Xiang Qu , Hui Zhao , Gongyi Wang , Jing Li , Zihan Huang

We consider the propagation of galactic cosmic rays under assumption that the interstellar medium is a fractal one. An anomalous diffusion equation in terms of fractional derivatives is used to describe of cosmic ray propagation. The…

Astrophysics · Physics 2007-05-23 A. A. Lagutin , V. V. Uchaikin

The solution of a nonlinear diffusion equation is numerically investigated using the generalized Fourier transform method. This equation includes fractal dimensions and power-law dependence on the radial variable and on the diffusion…

Computational Physics · Physics 2019-11-12 Jie Yao , Cameron L. Williams , Fazle Hussain , Donald J. Kouri

Anomalous diffusion often arises in complex environments where viscoelastic or crowded conditions influence particle motion. In many biological and soft-matter systems, distinct components of the medium exhibit unique viscoelastic…

Soft Condensed Matter · Physics 2026-01-05 Chan Lim , Jae-Hyung Jeon

Anomalous-diffusion, the departure of the spreading dynamics of diffusing particles from the traditional law of Brownian-motion, is a signature feature of a large number of complex soft-matter and biological systems. Anomalous-diffusion…

When considering fractional diffusion equation as model equation in analyzing anomalous diffusion processes, some important parameters in the model, for example, the orders of the fractional derivative or the source term, are often unknown,…

Analysis of PDEs · Mathematics 2019-04-15 Zhiyuan Li , Masahiro Yamamoto

A model linking the molecular-scale dynamics of fluids confined to nano-pores to nuclear magnetic resonance (NMR) relaxation rates is proposed. The model is fit to experimental NMR dispersions for water and oil in an oil shale assuming that…

Mesoscale and Nanoscale Physics · Physics 2017-04-05 David A Faux , Peter J McDonald

We present analytical results for the biased diffusion of particles moving under a constant force in a randomly layered medium. The influence of this medium on the particle dynamics is modeled by a piecewise constant random force. The…

Statistical Mechanics · Physics 2010-02-10 S. I. Denisov , H. Kantz

The problem of anomalous diffusion in the momentum space is considered on the basis of the appropriate probability transition function (PTF). New general equation for description of the diffusion of heavy particles in the gas of the light…

Statistical Mechanics · Physics 2015-05-13 S. A. Trigger

Progress in the theory of anomalous diffusion in weakly turbulent cold magnetized plasmas is explained. Several proposed models advanced in the literature are discussed. Emphasis is put on a new proposed mechanism for anomalous diffusion…

Plasma Physics · Physics 2009-01-26 Mario J. Pinheiro

A theoretical analysis of the anomalous diffusion transport mechanism suggests a possible connection between wall current drain and magnetic flux through the orbital trajectories of charged particles in a plasma submitted to a strong…

Plasma Physics · Physics 2007-05-23 Mario J. Pinheiro

The transport equation of active motion is generalised to consider time-fractional dynamics for describing the anomalous diffusion of self-propelled particles observed in many different systems. In the present study, we consider an…

Statistical Mechanics · Physics 2023-10-27 Francisco J. Sevilla , Guillermo Chacón-Acosta , Trifce Sandev

Diffusion in nonhomogeneous media is described by a dynamical process driven by a general Levy noise and subordinated to a random time; the subordinator depends on the position. This problem is approximated by a multiplicative process…

Statistical Mechanics · Physics 2015-06-18 Tomasz Srokowski

The diffusion/relaxation behavior of polarized spins of pore filling fluid, as often probed by NMR relaxometry, is widely used to extract information on the pore-geometry. Such information is further interpreted as an indicator of the key…

Soft Condensed Matter · Physics 2016-09-13 Seungoh Ryu , Weishu Zhao , Gabriela Leu , Philip M. Singer , Hyung Joon Cho , Youngseuk Keehm

We show analytically that there is anomalous diffusion when the diffusion constant depends on the concentration as a power law with a positive exponent or a negative exponent with absolute value less than one and the initial condition is a…

Statistical Mechanics · Physics 2019-12-13 Alex Hansen , Eirik G. Flekkøy

The motion of contaminant particles through complex environments such as fractured rocks or porous sediments is often characterized by anomalous diffusion: the spread of the transported quantity is found to grow sublinearly in time due to…

Statistical Mechanics · Physics 2009-11-13 M. Marseguerra , A. Zoia

The time-asymptotic behavior of undamped, nonlinear oscillators with a random frequency is investigated analytically and numerically. We find that averaged quantities of physical interest, such as the oscillator's mechanical energy,…

Statistical Mechanics · Physics 2009-11-07 Kirone Mallick , Philippe Marcq