# 11月28日 兰州大学王智诚教授学术报告

王智诚，男，甘肃庄浪人，兰州大学数学与统计学院教授，博士生导师。1994年本科毕业于西北师范大学，2007年在兰州大学获理学博士学位。在Trans. AMS、Arch. RationalMech. Anal.、SIAM J. Math. Anal.、SIAM J. Appl. Math.、JMPA、Calc. Var. PDE、JDE、JDDE、Nonlinearity等杂志发表SCI论文90多篇。2010年入选教育部新世纪优秀人才支持计划，2011和2019年分别获得甘肃省自然科学二等奖，2016年入选甘肃省飞天学者特聘教授，主持完成两项国家自然科学基金面上项目以及教育部博士点基金等多项省部级项目，正在主持一项甘肃省基础研究创新群体项目、一项国家自然科学基金面上项目并参加一项国家自然科学基金重点项目。目前担任两个SCI杂志International J.  Bifurc. Chaos 和Mathematical Biosciences and Engineering (MBE) 的编委（Associate editor）。

In this talk we consider the nonnegative bounded solutions for reaction-advection-diffusion equationsof the form $u_{t}-\Delta u+\alpha(t,y)u_{x}=f(t,y,u)$ in cylinders, where $f$is a bistable or multistable nonlinearity which is $T$-periodic in $t$. Weprove that under certain conditions, there are at most three types of solutionsfor any one-parameter family of initial data:  that spread to $1$ forlarge parameters, vanish to $0$ for small parameters, and  exhibitexceptional behaviors for intermediate parameters. We usually refer to the lastas the  threshold solutions. It is worth noting that we also give  asufficient condition for solutions to  spread to $1$  by proving akind of stability of  a pair of diverging traveling fronts.  Furthermore,under the additional conditions, by using super- and sub-solutions, Harnack'sinequality and the method of moving hyperplane, we show that any point in the$\omega$-limit set of the threshold solutions is symmetric with respect to $x$, and exponentially decays to $0$ as $|x|\to\infty$.