9月7日 日本东京大学丁维维博士学术报告

发布时间:2017-09-05浏览次数:83


报 告 人:丁维维 博士(日本东京大学)

报告题目:Spreading in space-time periodic media governed by a monostable equation with free boundaries

报告时间:2017年9月7日(周四)下午2:30-4:30

报告地点:静远楼204学术报告厅

报告人简介:

    丁维维,男,1987年8月出生,现为日本东京大学JSPS博士后研究员。 2005-2009,于苏州大学完成本科学习,2009-2015,获得中国科学技术大学博士学位,期间赴法国马赛大学联合培养两年,并获得博士学位。2015-2017,在澳大利亚新英格兰大学从事博士后研究工作。研究方向为几类非线性抛物方程的动力学性质。

报告摘要:

    This work is aimed at classifying the long-time behavior of the solution to a free boundary problem with monostable reaction term in space-time periodic media. Such a modelmay be used to describe the spreading of a new or invasive species with the free boundary representing the expanding front. In Part 1 of this work, we establish a theory on theexistence and uniqueness of solutions to this free boundary problem with continuous initial functions, as well as comparisonresults, and spreading-vanishing dichotomy. In Part 2, we develop the methods of Weinberger to prove the existence of asymptotic spreading speed when spreading happens,without knowing a priori the existence of the corresponding semi-wave solutions of the free boundary problem. This is a different approach from earlier works on the free boundary model, where the spreading speed is determined by firstly showing the existence of a corresponding semi-wave.