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.