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排序方式: 共有311条查询结果,搜索用时 17 毫秒
301.
302.
In this paper,a reaction-diffusion system is proposed to investigate avian-human influenza.Two free boundaries are introduced to describe the spreading frontiers of the avian influenza.The basic reproduction numbers rF0(t)and RF0(t)are defined for the bird with the avian influenza and for the human with the mutant avian influenza of the free boundary problem,respectively.Properties of these two time-dependent basic reproduction numbers are obtained.Sufficient conditions both for spreading and for vanishing of the avian influenza are given.It is shown that if rF0(0)<1 and the initial number of the infected birds is small,the avian influenza vanishes in the bird world.Furthermore,if rF0(0)<1 and RF0(0)<1,the avian influenza vanishes in the bird and human worlds.In the case that rF0(0)<1 and RF0(0)>1,spreading of the mutant avian influenza in the human world is possible.It is also shown that if rF0(t0)>1 for any t0>0,the avian influenza spreads in the bird world. 相似文献
303.
Dmitriy Leykekhman. 《Mathematics of Computation》2008,77(261):21-39
Consider the problem with homogeneous Neumann boundary condition in a bounded smooth domain in . The whole range is treated. The Galerkin finite element method is used on a globally quasi-uniform mesh of size ; the mesh is fixed and independent of .
A precise analysis of how the error at each point depends on and is presented. As an application, first order error estimates in , which are uniform with respect to , are given.
304.
在齐次Neumann边界条件下研究一类Degn-Harrison反应扩散系统.首先讨论常微分系统正平衡点的稳定性和Hopf分支,其次研究扩散系统,给出扩散系数对正平衡点稳定性的影响,建立系统的Turing不稳定性,同时在扩散系数满足一定条件时给出Hopf分支的存在性. 相似文献
305.
In this paper, we investigate the long time behavior of non-Fickian delay reaction-diffusion equations. These kinds of Volterra integro-differential equations are derived by combining a time memory term in the flux and a delay parameter in the reaction term. Energy estimates, dissipativity, asymptotic stability, and contractivity of the problems are obtained. Moreover, we prove that the numerical method discussed in the present paper has the ability to preserve stability and contractivity of the underlying systems. Some confirmations of these are illustrated by using the numerical method on two biological models. 相似文献
306.
一类反应扩散方程解的熄灭现象 总被引:4,自引:0,他引:4
利用能量估计方法讨论了下述反应扩散方程的初边值问题解的渐近性态,分别给出解熄灭的充分条件和必要条件。这里λ>0,γ>0,β>0为常数,Ω?RN为有界域。文末给出说明文中方法处理高阶方程的例子。 相似文献
307.
Traveling Wave Fronts of Reaction-Diffusion Systems with Delay 总被引:18,自引:0,他引:18
This paper deals with the existence of traveling wave front solutions of reaction-diffusion systems with delay. A monotone
iteration scheme is established for the corresponding wave system. If the reaction term satisfies the so-called quasimonotonicity
condition, it is shown that the iteration converges to a solution of the wave system, provided that the initial function for
the iteration is chosen to be an upper solution and is from the profile set. For systems with certain nonquasimonotone reaction
terms, a convergence result is also obtained by further restricting the initial functions of the iteration and using a non-standard
ordering of the profile set. Applications are made to the delayed Fishery–KPP equation with a nonmonotone delayed reaction
term and to the delayed system of the Belousov–Zhabotinskii reaction model.
An erratum to this article is available at . 相似文献
308.
In this letter, a class of reaction-diffusion equations, which arise
in chemical reaction or ecology and other fields of physics, are investigated.
A more general analytical solution of the equation is obtained by using the
first integral method. 相似文献
309.
In this paper, the target wave patterns of a reaction-diffusion process were discovered by numerical simulation of an immobilized
enzyme mathematical model. The substrate concentration periodically diffuses from initial state to all around, and the product
concentration also periodically increases with target wave patterns, and finally they reach the equilibrium states. 相似文献
310.
In this paper, we prove the existence of critical Fujita exponents for a class of nonlocal reaction diffusion systems. And it is proved that the critical Fujita exponents belong to the blow up case. 相似文献