The existence of positive solution for singular boundary value problems of first order differential equation on unbounded domains

By constructing a special cone and using cone compression and expansion fixed point theorem, this paper presents some existence results of positive solutions of singular boundary value problem on unbounded domains for a class of first order differential equation. As applications of the main results, two examples are given at the end of this paper. Supported by the National Natural Science Foundation of China (No. 10671167) and the Natural Science Foundation of Liaocheng University (31805).     

BIFURCATIONS OF TRAVELLING WAVE SOLUTIONS FOR THE GENERALIZED DODD-BULLOUGH-MIKHAILOV EQUATION

In this paper, the generalized Dodd-Bullough-Mikhailov equation is studied. The existence of periodic wave and unbounded wave solutions is proved by using the method of bifurcation theory of dynamical systems. Under different parametric conditions, various sufficient conditions to guarantee the existence of the above solutions are given.Some exact explicit parametric representations of the above travelling solutions are obtained.     

A global compact result for a semilinear elliptic problem with Hardy potential and critical nonlinearities on R~N

In this paper, we are concerned with the following class of elliptic problems:where 2 = 2N/(N-2) is the critical Sobolev exponent, 2 q 2 , 0≤μ μˉ=(N-2)2_4 , a(x), k(x) ∈ C(RN ). Through a compactness analysis of the functional corresponding to the problems , we obtain the existence of positive solutions for this problem under certain assumptions on a(x) and k(x).     

无穷区间上一阶奇异微分方程正解的存在性和不可比较性

By constructing a special cone and applying the fixed point theorem of cone compression and expansion, this paper investigates the existence of positive solutions for a class of first order singular boundary value problem （BVP, for short） on unbounded domains. Moreover, an incomparable result about two positive solutions for the BVP is also obtained and an example is given to illustrate the application of the main results.     

(2+1)-维广义Benney-Luke方程的精确行波解

用平面动力系统方法研究(2+1)-维广义Benney-Luke方程的精确行波解,获得了该方程的扭波解,不可数无穷多光滑周期波解和某些无界行波解的精确的参数表达式,以及上述解存在的参数条件．     

非Fourier温度场分布的奇摄动解

应用非Fourier热传导定律构建了单层材料中温度场模型,即一类在无界域上带小参数的奇摄动双曲方程,通过奇摄动展开方法,得到了该问题的渐近解.首先应用奇摄动方法得到了该问题的外解和边界层矫正项,通过对内解和外解的最大模估计和关于时间导数的最大模估计以及线性抛物方程理论,得到了内外解的存在唯一性,从而得到了解的形式渐近展开式.通过余项估计,给出了渐近解的L²估计,得到了渐近解的一致有效性,从而得到了无界域上温度场的分布.通过奇摄动分析,给出了非Fourier 温度场与Fourier 温度场的关系,描述了非Fourier温度场的具体形态.     

Periodic Solutions of Nonlinear Wave Equations with Dissipative Boundary Conditions

Applying Nash-Moser's implicit function theorem, the author proves the existence of periodic solution to nonlinear wave equation u_{tt} - u_{xx} + εg(t, x, u, u_t, u_x, u_{tt}, u_{tx}, u_{xx}) = 0 with a dissipative boundary condition, provided ε is sufficiently small.     

广义特殊Tzitzeica-Dodd-Bullough类型方程的行波解

本文研究了广义特殊Tzitzeica-Dodd-Bullough类型方程,利用动力系统分支理论方法,证明该方程存在周期行波解,无界行波解和破切波解,并求出了一些用参数表示的显示精确行波解.     

A NON-OVERLAPPING DOMAIN DECOMPOSITION ALGORITHM BASED ON THE NATURAL BOUNDARY REDUCTION FOR WAVE EQUATIONS IN AN UNBOUNDED DOMAIN

In this paper, a new domain decomposition method based on the natural boundary reduction, which solves wave problems over an unbounded domain, is suggestted. An circular artificial boundary is introduced. The original unbounded domain is divided into two subdomains, an internal bounded region and external unbounded region outside the artificial boundary. A Dirichlet-Neumann(D-N) alternating iteration algorithm is constructed. We prove that the algorithm is equavilent to preconditional Richardson iteration method. Numerical studies are performed by finite element method. The numerical results show that the convergence rate of the discrete D-N iteration is independent of the finite element mesh size.     

Compact attractor for weakly damped driven Korteweg-de Vries equations on the real line

We investigate the long-time behaviour of solutions to the Korteweg-de Vries equation with a zero order dissipation and an additional forcing term, when the space variable varies over , and prove that it is described by a maximal compact attractor in H ²().     

带有无界时滞的积分微分方程的正解

我们得到一类带有无界时滞的积分微分方程存在正解的必要充分条件.     

Pullback attractors for the non-autonomous Benjamin-Bona-Mahony equation in unbounded domains

The existence of a pullback attractor is proven for the non-autonomous Benjamin-Bona-Mahony equation in unbounded domains.The asymptotic compactness of the solution operator is obtained by the uniform estimates on the tails of solutions.     

Logistic型方程周期解和概周期解的存在性

In this paper, we study the Logistic type equation x= a（t）x -b（t）x^2＋ e（t）. Under the assumptions that e（t） is small enough and a（t）, b（t） are contained in some positive intervals, we prove that this equation has a positive bounded solution which is stable. Moreover, this solution is a periodic solution if a（t）, b（t） and e（t） are periodic functions, and this solution is an almost periodic solution if a（t）, b（t） and e（t） are almost periodic functions.     

耗散MKdV方程的指数吸引子

讨论了无界区域R~1上的MKdV方程,运用带权空间构造一类紧算子和算子分解的方法,得到该方程在H~2（R~1）上指数吸引子的存在性.     

时间测度上一些种群动力学方程的周期解

在时间测度上研究一些具有时滞的种群动力学系统,利用Mawhin重合度理论建立了这一类抽象型系统的正周期解存在的充分性条件,从而使这些种群动力学模型的连续和离散时间情形,即微分方程和差分方程得到了统一研究.将所得到的结论可以应用到很多具体的生物数学模型上.     

Positive unbounded solutions of second order quasilinear ordinary differential equations and their application to elliptic problems

In this paper we consider positive unbounded solutions of second order quasilinear ordinary differential equations. Our objective is to determine the asymptotic forms of unbounded solutions. An application to exterior Dirichlet problems is also given.