arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1502.05617math.AP
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具有体积填充的退化交叉扩散种群模型的分析

Analysis of degenerate cross-diffusion population models with volume filling

Nicola Zamponi, Ansgar Jüngel

摘要:

在有界区域中研究了一类抛物型交叉扩散方程组,该方程组描述了任意数量种群间的相互作用,具有无通量边界条件。该方程是从扩散极限下的随机行走晶格模型中推导出来的。与文献中的结果相比,新颖之处在于一般退化扩散和体积填充效应的结合。非线性扩散系数的条件被确定,从而产生一个正式的梯度流或熵结构。这种结构允许证明有界弱解的整体存在性和解的指数收敛到常数稳态。存在性证明是基于一个近似参数,熵不等式,和新的非线性奥宾狮子紧引理。利用熵估计和凸Sobolev不等式证明了系统的大时间行为。在非线性条件下,利用$H^{-1}$方法、Gastroski的$E$ -单调性技巧和Fisher信息的次可加性,证明了弱解的唯一性.

英文摘要:

A class of parabolic cross-diffusion systems modeling the interaction of an arbitrary number of population species is analyzed in a bounded domain with no-flux boundary conditions. The equations are formally derived from a random-walk lattice model in the diffusion limit. Compared to previous results in the literature, the novelty is the combination of general degenerate diffusion and volume-filling effects. Conditions on the nonlinear diffusion coefficients are identified, which yield a formal gradient-flow or entropy structure. This structure allows for the proof of global-in-time existence of bounded weak solutions and the exponential convergence of the solutions to the constant steady state. The existence proof is based on an approximation argument, the entropy inequality, and new nonlinear Aubin-Lions compactness lemmas. The proof of the large-time behavior employs the entropy estimate and convex Sobolev inequalities. Moreover, under simplifiying assumptions on the nonlinearities, the uniqueness of weak solutions is shown by using the $H^{-1}$ method, the $E$-monotonicity technique of Gajewski, and the subadditivity of the Fisher information.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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