Extinction and blow-up phenomena in a non-linear gender structured population model

In this article we consider a gender structured model in population dynamics. We assume that the fertility rate depends upon the weighted population of males instead of total population of males. The proportion of males in the population is determined by fixed environmental or social conditions. Here we prove an existence and uniqueness result for a non-trivial steady state. If the initial age distribution is uniformly below the non-trivial steady state then we show that the total population goes extinct in infinite time. On the other hand, if we take the initial age distribution to be uniformly above the steady state then the total population blows up exponentially with time.     

一类非线性耗色散方程解的Blow—up

本文研究一类四阶非线性耗、色散波动方程的补边值问题,在一定条件下,得到了方程解的blow up性质。     

Global Existence and Blow-up for Semilinear Wave Equations with Variable Coefficients

The authors consider the critical exponent problem for the variable coefficients wave equation with a space dependent potential and source term. For sufficiently small data with compact support, if the power of nonlinearity is larger than the expected exponent, it is proved that there exists a global solution. Furthermore, the precise decay estimates for the energy, L₂ and L^p+1 norms of solutions are also established. In addition, the blow-up of the solutions is proved for arbitrary initial data with compact support when the power of nonlinearity is less than some constant.     

一反应扩散方程组存在解的条件

讨论了下述反应扩散方程组的初边值问题其中ｐ，ｑ＞１，我们得到了问题（Ｐ）存在局部和整体解的必要条件，并证得当初值适当大时，解在有限时刻发生Ｂｌｏｗｕｐ现象。     

Global well‐posedness and blow‐up criterion for the periodic quasi‐geostrophic equations in Lei‐Lin‐Gevrey spaces

In this paper we consider a periodic 2‐dimensional quasi‐geostrophic equations with subcritical dissipation. We show the global existence and uniqueness of the solution for small initial data in the Lei‐Lin‐Gevrey spaces . Moreover, we establish an exponential type explosion in finite time of this solution.     

一类四阶非线性波动方程的初边值问题

本文研究一类描述非线性粘弹性杆中纵波振动的非线性波动方程的初边值问题,用Ｇａｌｅｒｋｉｎ方法证明了其整体强解的存在性,唯一性,最后讨论了解的渐近性质及在一定条件下整体解的不存在性。