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Related papers: Fractional Gray-Scott Model: Well-posedness, Discr…

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In the Gray-Scott reaction-diffusion system one reactant is constantly fed in the system, another reactant is reproduced by consuming the supplied reactant and also converted to an inert product. The rate of feeding one reactant in the…

Pattern Formation and Solitons · Physics 2016-10-31 Andrew Adamatzky

A second-order accurate in time, positivity-preserving, and unconditionally energy stable operator splitting numerical scheme is proposed and analyzed for the system of reaction-diffusion equations with detailed balance. The scheme is…

Numerical Analysis · Mathematics 2021-09-08 Chun Liu , Cheng Wang , Yiwei Wang

The present work provides a critical assessment of numerical solutions of the space-fractional diffusion-advection equation, which is of high significance for applications in various natural sciences. In view of the fact that, in contrast…

Statistical Mechanics · Physics 2014-10-27 Robin Stern , Frederic Effenberger , Horst Fichtner , Tobias Schaefer

This paper presents an efficient and concise double fast algorithm to solve high dimensional time-space fractional diffusion problems with spectral fractional Laplacian. We first establish semi-discrete scheme of time-space fractional…

Numerical Analysis · Mathematics 2024-04-16 Yi Yang , Jin Huang

A non-stationary spatial Gaussian random field (GRF) is described as the solution of an inhomogeneous stochastic partial differential equation (SPDE), where the covariance structure of the GRF is controlled by the coefficients in the SPDE.…

Methodology · Statistics 2016-08-11 Geir-Arne Fuglstad , Daniel Simpson , Finn Lindgren , Håvard Rue

This article devotes to developing robust but simple correction techniques and efficient algorithms for a class of second-order time stepping methods, namely the shifted fractional trapezoidal rule (SFTR), for subdiffusion problems to…

Numerical Analysis · Mathematics 2020-10-26 Baoli Yin , Yang Liu , Hong Li , Zhimin Zhang

Recent advances in generative modeling with diffusion processes (DPs) enabled breakthroughs in image synthesis. Despite impressive image quality, these models have various prompt compliance problems, including low recall in generating…

Computer Vision and Pattern Recognition · Computer Science 2024-10-30 Deepak Sridhar , Abhishek Peri , Rohith Rachala , Nuno Vasconcelos

In this paper Gaussian models of retarded and accelerated anomalous diffusion are considered. Stochastic differential equations of fractional order driven by single or multiple fractional Gaussian noise terms are introduced to describe…

Statistical Mechanics · Physics 2014-05-08 Chai Hok Eab , S. C. Lim

In 1986, Dixon and McKee developed a discrete fractional Gr\"{o}nwall inequality [Z. Angew. Math. Mech., 66 (1986), pp. 535--544], which can be seen as a generalization of the classical discrete Gr\"{o}nwall inequality. However, this…

Numerical Analysis · Mathematics 2021-04-08 Hui Zhang , Fanhai Zeng , Xiaoyun Jiang , George Em Karniadakis

Diffusion models have recently attained significant interest within the community owing to their strong performance as generative models. Furthermore, its application to inverse problems have demonstrated state-of-the-art performance.…

Image and Video Processing · Electrical Eng. & Systems 2022-03-22 Hyungjin Chung , Byeongsu Sim , Jong Chul Ye

Fractional Gaussian noise models the time series with long-range dependence; when the Hurst index $H>1/2$, it has positive correlation reflecting a persistent autocorrelation structure. This paper studies the numerical method for solving…

Numerical Analysis · Mathematics 2020-07-29 Daxin Nie , Jing Sun , Weihua Deng

We present new numerical schemes to integrate stochastic partial differential equations which describe the spatio-temporal dynamics of reaction-diffusion (RD) problems under the effect of internal fluctuations. The schemes conserve the…

Statistical Mechanics · Physics 2009-11-10 Esteban Moro

A time-stepping L1 scheme for subdiffusion equation with a Riemann--Liouville time-fractional derivative is developed and analyzed. This is the first paper to show that the L1 scheme for the model problem under consideration is second-order…

Numerical Analysis · Mathematics 2019-09-17 Kassem Mustapha

In this paper, we present GGSD, a novel graph generative model based on 1) the spectral decomposition of the graph Laplacian matrix and 2) a diffusion process. Specifically, we propose to use a denoising model to sample eigenvectors and…

Machine Learning · Computer Science 2025-03-05 Giorgia Minello , Alessandro Bicciato , Luca Rossi , Andrea Torsello , Luca Cosmo

Typical generative diffusion models rely on a Gaussian diffusion process for training the backward transformations, which can then be used to generate samples from Gaussian noise. However, real world data often takes place in discrete-state…

Machine Learning · Computer Science 2023-05-19 Javier E Santos , Zachary R. Fox , Nicholas Lubbers , Yen Ting Lin

A key objective in spatial statistics is to simulate from the distribution of a spatial process at a selection of unobserved locations conditional on observations (i.e., a predictive distribution) to enable spatial prediction and…

Methodology · Statistics 2025-11-17 Julia Walchessen , Andrew Zammit-Mangion , Raphaël Huser , Mikael Kuusela

In this contribution, a wave equation with a time-dependent variable-order fractional damping term and a nonlinear source is considered. Avoiding the circumstances of expressing the nonlinear variable-order fractional wave equations via…

Numerical Analysis · Mathematics 2023-07-17 Karel Van Bockstal , Mahmoud A. Zaky , Ahmed S. Hendy

In this work, we analyze a Crank-Nicolson type time stepping scheme for the subdiffusion equation, which involves a Caputo fractional derivative of order $\alpha\in (0,1)$ in time. It hybridizes the backward Euler convolution quadrature…

Numerical Analysis · Mathematics 2017-02-28 Bangti Jin , Buyang Li , Zhi Zhou

In this paper, we focus on designing a well-conditioned Glarkin spectral methods for solving a two-sided fractional diffusion equations with drift, in which the fractional operators are defined neither in Riemann-Liouville nor Caputo sense,…

Numerical Analysis · Mathematics 2019-09-13 Lijing Zhao , Xudong Wang

Implantation of neuroprosthetic electrodes induces a stereotypical state of neuroinflammation, which is thought to be detrimental for the neurons surrounding the electrode. Mechanisms of this type of neuroinflammation are still not…

Tissues and Organs · Quantitative Biology 2015-12-15 Dimiter Prodanov , Jean Delbeke