一类具有多项式型边界记忆项的非线性热方程解的整体存在与爆破

本文研究一类具有多项式型边界记忆项的非线性热方程的解的长时间行为,首先建立比较原理并证明经典解的局部存在性;接下来利用比较原理和Green函数研究解的整体存在和爆破;最后讨论边界爆破并给出爆破速率估计.     

具非局部源退化抛物型方程组的一致爆破模式

考虑带有齐次Dirichlet边界条件且具有非局部源项的退化抛物型方程组正解的爆破性质. 在适当条件下, 建立了该问题解的局部存在性并证明解在有限时刻爆破, 此外,还导出了解的两个分量同时爆破的必要条件, 并得到了该问题解的一致爆破模式.     

具有阻尼项的非线性KG方程的柯西问题

首先,介绍位势井及位势井族,并由定义证明其性质;其次,证明整体解的不变性;最后得到了整体解的存在定理,并得到了有限时间内解的爆破.     

一类反应扩散方程的爆破时间下界估计

该文讨论了一类反应项为非线性非局部热源且热汇具有时间系数的反应扩散方程,分别在Dirichlet、Neumann或Robin边界条件下,在有界区域中的爆破行为.若解可能在有限时间发生爆破,通过构造合适的辅助函数,对时间系数给出适当的条件,利用Sobolev、H?lder不等式及Payne和Schaefer积分不等式等技巧,得出了解的爆破时间下界的估计.     

三维可压缩Euler方程球对称解的生命区间

对于可压缩的三维Ｅｕｌｅｒ方程，当其初值为振幅ε的小扰动且具有球对称性质时，我们研究了经典解的生命区间．并证明无论初值的扰动多么小，经典解都在有限时间内爆破．     

具广义非线性源的波动方程的高能爆破

研究一类具广义非线性源的非线性波动方程的初边值问题在高初始能级状态下解的有限时间爆破.利用经典的凹函数方法找到了导致该问题具任意正初始能级的解有限时间爆破的初值.     

一类拟线性抛物方程解的Blow—up

本文讨论了拟线性抛物方程具有第三类非线性边界条件的解的爆破性质,证明了解在有限时刻T_0爆破。     

二维等熵可压欧拉方程古典解的存在性(英文)

研究二维等熵可压缩欧拉方程的古典解存在性.利用迭代技巧,得到解的局部存在性及唯一性,并且还证明了解在有限时间内爆破,即可压缩欧拉方程不存在全局古典解.     

关于带梯度的波动方程解的blow—up性质

本文讨论了一个带有梯度的非线性波动方程解的爆破性质,证明了解在有限时间内爆破,推广了文[1]的结果.     

高维非线性拋物型方程在非线性边界通量作用下的爆破现象北大核心CSCD

本文研究了具有非线性边界通量高维非线性抛物型方程.通过建立一个辅助函数,利用微分不等式技术,确定了一类定义在ΩR^(N)(N≥3)上的一个有界非线性抛物型方程非负经典解爆破时间的下界,并得到了全局解的存在条件.     

Blow-Up of the solution of the initial boundary-value problem for the generalized Boussinesq equation with nonlinear boundary condition

The initial boundary-value problem for a nonlinear equation of pseudoparabolic type with nonlinear Neumann boundary condition is considered. We prove a local theorem on the existence of solutions. Using the method of energy inequalities, we obtain sufficient conditions for the blow-up of solutions in a finite time interval and establish upper and lower bounds for the blow-up time.     

Blow-up and lifespan of solutions to a nonlocal parabolic equation at arbitrary initial energy level

We consider a nonlocal parabolic equation. By exploiting the boundary condition and the variational structure of the equation, we prove finite time blow-up of the solution for initial data at arbitrary energy level. We also obtain the lifespan of the blow-up solution. The results generalize the former studies on this equation.     

Blow-up phenomena for a semilinear heat equation with nonlinear boundary condition, II

This paper deals with the blow-up of the solution to a semilinear second-order parabolic equation with nonlinear boundary conditions. It is shown that under certain conditions on the nonlinearities and data, blow-up will occur at some finite time and when blow-up does occur upper and lower bounds for the blow-up time are obtained.     

A semilinear equation with generalized Wentzell boundary condition

In this paper we consider a semilinear equation with a generalized Wentzell boundary condition. We prove the local well-posedness of the problem and derive the conditions of the global existence of the solution and the conditions for finite time blow-up. We also derive an estimate for the blow-up time.     

Blow－Up and Mass Concentration of Solutions to the Cauchy Problem for Nonlinear Schrodinger Equations

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Dynamic properties for nonlinear viscoelastic Kirchhoff-type equation with acoustic control boundary conditions II

In this paper, we consider the nonlinear viscoelastic Kirchhoff-type equation with initial conditions and acoustic boundary conditions. Under suitable conditions on the initial data, the relaxation function $h(\cdot)$ and $M(\cdot)$, we prove that the solution blows up in finite time and give the upper bound of the blow-up time $T^*$.     

A semilinear parabolic system with generalized Wentzell boundary condition

In this paper, we consider a weak coupled semilinear parabolic system with general Wentzell boundary condition. We prove the well-posedness of the problem and derive different conditions in terms of the powers of the nonlinear terms under which the global solution exists and finite time blow-up occurs.     

On the nonextendable solution and blow-up of the solution of the one-dimensional equation of ion-sound waves in a plasma

The initial boundary-value problem for the equation of ion-sound waves in a plasma is studied. A theorem on the nonextendable solution is proved. Sufficient conditions for the blow-up of the solution in finite time and the upper bound for the blow-up time are obtained using the method of test functions.     

一个反应—扩散方程组解的整体存在与有限时刻爆破

研究一类带有非局部边界条件的抛物型方程组解的整体存在与有限刻爆破.主要通过构造上、下解,利用比较原理得到定理的证明.     

Blow-up sets for linear diffusion equations in one dimension

We consider the heat equation in the half-line with Dirichlet boundary data which blow up in finite time. Though the blow-up set may be any interval [0,a], a ? [0,￥]a\in[0,\infty] depending on the Dirichlet data, we prove that the effective blow-up set, that is, the set of points x 3 0x\ge0 where the solution behaves like u(0,t), consists always only of the origin. As an application of our results we consider a system of two heat equations with a nontrivial nonlinear flux coupling at the boundary. We show that by prescribing the non-linearities the two components may have different blow-up sets. However, the effective blow-up sets do not depend on the coupling and coincide with the origin for both components.