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Related papers: Homogenization for Space-Time-Dependent KPP Reacti…

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This paper concerns the nonautonomous reaction-diffusion equation \[ u_t=u_{xx}+ug(t,x-ct,u), \quad t>0,x\in\mathbb{R}, \] where $c\in\mathbb{R}$ is the shifting speed, and the time periodic nonlinearity $ug(t,\xi,u)$ is asymptotically of…

Analysis of PDEs · Mathematics 2020-05-05 Jian Fang , Rui Peng , Xiao-Qiang Zhao

The present paper is devoted to the study of transition fronts in nonlocal reaction-diffusion equations with time heterogeneous nonlinearity of ignition type. It is proven that such an equation admits space monotone transition fronts with…

Analysis of PDEs · Mathematics 2015-07-10 Wenxian Shen , Zhongwei Shen

This paper is devoted to the analysis of the large-time behavior of solutions of one-dimensional Fisher-KPP reaction-diffusion equations. The initial conditions are assumed to be globally front-like and to decay at infinity towards the…

Analysis of PDEs · Mathematics 2009-06-18 Francois Hamel , Lionel Roques

We study in this paper the periodic homogenization problem related to a strongly nonlinear reaction-diffusion equation. Owing to the large reaction term, the homogenized equation has a rather quite different form which puts together both…

Analysis of PDEs · Mathematics 2012-05-01 Nils Svanstedt , Jean Louis Woukeng

We consider Fisher-KPP-type reaction-diffusion equations with spatially inhomogeneous reaction rates. We show that a sufficiently strong localized inhomogeneity may prevent existence of transition-front-type global in time solutions while…

Analysis of PDEs · Mathematics 2015-05-20 James Nolen , Jean-Michel Roquejoffre , Lenya Ryzhik , Andrej Zlatos

We consider a space-inhomogeneous Kolmogorov-Petrovskii-Piskunov (KPP) equation with a nonlocal diffusion and an almost-periodic nonlinearity. By employing and adapting the theory of homogenization, we show that solutions of this equation…

Analysis of PDEs · Mathematics 2016-01-19 Yan Zhang

In this paper, we study the propagation speeds of reaction-diffusion-advection (RDA) fronts in time-periodic cellular and chaotic flows with Kolmogorov-Petrovsky-Piskunov (KPP) nonlinearity. We first apply the variational principle to…

Numerical Analysis · Mathematics 2021-05-18 Junlong Lyu , Zhongjian Wang , Jack Xin , Zhiwen Zhang

We consider in this paper a reaction-diffusion system in presence of a flow and under a KPP hypothesis. While the case of a single-equation has been extensively studied since the pioneering Kolmogorov-Petrovski-Piskunov paper, the study of…

Analysis of PDEs · Mathematics 2015-05-18 Thomas Giletti

We investigate in this paper propagation phenomena for the heterogeneous reaction-diffusion equation $\partial_t u -\Delta u = f(t,u)$, $x\in R^N$, $t\in\R$, where f=f(t,u) is a KPP monostable nonlinearity which depends in a general way on…

Analysis of PDEs · Mathematics 2011-05-03 Grégoire Nadin , Luca Rossi

In this series of papers, we investigate the spreading and vanishing dynamics of time almost periodic diffusive KPP equations with free boundaries. Such equations are used to characterize the spreading of a new species in time almost…

Dynamical Systems · Mathematics 2015-07-08 Fang Li , Xing Liang , Wenxian Shen

We prove the existence of Kolmogorov-Petrovsky-Piskunov (KPP) type traveling fronts in space-time periodic and mean zero incompressible advection, and establish a variational (minimization) formula for the minimal speeds. We approach the…

Analysis of PDEs · Mathematics 2007-05-23 James Nolen , Matthew Rudd , Jack Xin

This paper is devoted to propagation phenomena for a reaction-diffusion-advection equation in a one-dimensional heterogeneous environment, where heterogeneity is reflected by the nonlinearity term -- being KPP type on $(-\infty, -L]$ and…

Analysis of PDEs · Mathematics 2024-10-04 Xing Liang , Lei Zhang , Mingmin Zhang

In this series of papers, we investigate the spreading and vanishing dynamics of time almost periodic diffusive KPP equations with free boundaries. Such equations are used to characterize the spreading of a new species in time almost…

Analysis of PDEs · Mathematics 2015-07-08 Fang Li , Xing Liang , Wenxian Shen

Homogenization of a stochastic nonlinear reaction-diffusion equation with a large non- linear term is considered. Under a general Besicovitch almost periodicity assumption on the coefficients of the equation we prove that the sequence of…

Probability · Mathematics 2014-08-12 Paul André Razafimandimby , Mamadou Sango , Jean Louis Woukeng

Reaction-advection-diffusion equations, in periodic settings and with general type nonlinearities, admit a threshold known as the minimal speed of propagation. The minimal speed does not have an accessible formula when the nonlinearity is…

Analysis of PDEs · Mathematics 2020-01-17 Mohammad El Smaily , Chunhua Ou

We are interested in the time asymptotic location of the level sets of solutions to Fisher-KPP reaction-diffusion equations with fractional diffusion in periodic media. We show that the speed of propagation is exponential in time, with a…

Analysis of PDEs · Mathematics 2012-09-24 Xavier Cabre , Anne-Charline Coulon , Jean-Michel Roquejoffre

This paper is concerned with the spatio-temporal dynamics of nonnegative bounded entire solutions of some reaction-diffusion equations in R N in any space dimension N. The solutions are assumed to be localized in the past. Under certain…

Analysis of PDEs · Mathematics 2020-05-18 F. Hamel , H Ninomiya

We consider here a model of accelerating fronts, introduced in [2], consisting of one equation with nonlocal diffusion on a line, coupled via the boundary condition with a reaction-diffusion equation of the Fisher-KPP type in the upper…

Analysis of PDEs · Mathematics 2019-11-11 Anne-Charline Chalmin , Jean-Michel Roquejoffre

We use a new method in the study of Fisher-KPP reaction-diffusion equations to prove existence of transition fronts for inhomogeneous KPP-type non-linearities in one spatial dimension. We also obtain new estimates on entire solutions of…

Analysis of PDEs · Mathematics 2011-03-17 Andrej Zlatos

We study the qualitative homogenization of second order viscous Hamilton-Jacobi equations in space-time stationary ergodic random environments. Assuming that the Hamiltonian is convex and superquadratic in the momentum variable (gradient)…

Analysis of PDEs · Mathematics 2017-02-07 Wenjia Jing , Panagiotis E. Souganidis , Hung V. Tran