一类多时滞微分方程初值问题解的存在唯一性

研究了一类多时滞微分方程初值问题解的存在唯一性,用Picard方法证明了这类初值问题解的存在唯一性结论,它是常微分方程基本理论中著名的Picard存在唯一性定理的推广.     

一类分数阶中立型延迟微分方程的渐近稳定性

本文讨论了一类分数阶线性中立型延迟微分方程初值问题的解渐近稳定的充分必要条件.另外,本文还设计了数值求解这类分数阶中立型延迟微分方程初值问题的Hermite三次样条配置方法,并获得了局部截断误差结果.数值结果也验证了本文的理论结果.     

Langmuir扰动方程和Zakharov方程:光滑性与近似

考虑了一类带参数H,用于描述Langmuir扰动的方程.研究了当参数H趋于0时,这一类扰动方程的渐近行为.通过建立一个弱收敛结果和一个强收敛结果,得到了这类扰动方程初值问题的解(EH,nH)收敛到Zakharov方程初值问题的解(E,n)的结论.     

一类高阶多维非线性Schrodinger方程组的有限元分析

的初值问题和周期初值问题,得到了解的存在唯一性。本文讨论这类方程组的周期初值问题的有限元解法,对其半离散Galerkin有限元和全离散格式讨论了收敛阶,最后用Brower不动定理证明了全离散后所得到的非线性方程组的可解性。     

高阶非线性抛物型偏微分方程组的初值问题

本文讨论一般自治型高阶非线性抛物型偏微分方程组初值问题整体解的存在性，得到了这类问题对小初值存在整体经典解的充分条件。     

多步Runge-Kutta方法的保单调性

一类重要的常微分方程源自用线方法求解非线性双曲型 偏微分方程,这类常微分方程的解具有单调性, 因此要求数值方法能保持原系统的这种性质.本文研究多步Runge-Kutta方法求解常微分方程初值问题的保单调性.分别获得了多步Runge-Kutta方法是条件单调和无条件单调的充分条件.       

一类二阶线性周期边值问题解的存在唯一性的构造性证明

本文利用初值问题方法给出了一类二阶线性周期边值问题解的存在唯一性的构造性证明,并利用数值延拓方法,给出了计算实例。因此提供了一种大范围求解这类方程周期解的方法。     

凸幂凝聚算子的不动点定理及其对抽象半线性发展方程的应用

从应用问题的需要出发,给出了一类新的算子-凸幂凝聚算子的定义,推广了凝聚算子的概念,并证明了这类新算子的不动点定理,从而推广了著名的Schauder不动点定理和Sadovskii不动点定理.作为应用,获得了Banach空间中一类具有非紧半群的半线性发展方程初值问题整体mild解和正mild解的存在性.     

Banach空间中混合型积分-微分方程解的存在性

将微分方程初值问题转化为等价的积分方程,近来此方法被应用于讨论非线性微分方程初值问题解的存在性.利用凸幂凝聚算子的不动点定理,研究了Banach空间中混合型非线性二阶积分-微分方程的初值问题解的存在性.     

一类广义层流方程初值问题的整体适定性

讨论了刻画层流问题中比重相近的层间相互作用的数学模型的初值问题.通过引进一类函数空间并证明该初值问题的解在所述空间上的一系列先验估计,得到了该初值问题在初值属于Hs(R)(s≥1)时的整体适定性.     

Continuity of Solutions of a Class of Fractional Equations

In practice many problems related to space/time fractional equations depend on fractional parameters. But these fractional parameters are not known a priori in modelling problems. Hence continuity of the solutions with respect to these parameters is important for modelling purposes. In this paper we will study the continuity of the solutions of a class of equations including the Abel equations of the first and second kind, and time fractional diffusion type equations. We consider continuity with respect to the fractional parameters as well as the initial value.     

在部分区域上的奇摄动反应扩散方程初始边值问题解的渐近性态

讨论一类在部分区域上的奇摄动反应扩散方程初始边值问题,利用算子理论,得到了相应问题解的渐近性态。     

Fixed point theorems for a class of nonlinear operators in Banach spaces and applications

In this paper, we study a class of nonlinear operator equations with more extensive conditions in ordered Banach spaces. By using the cone theory and Banach contraction mapping principle, the existence and uniqueness of solutions for such equations are investigated without demanding the existence of upper and lower solutions and compactness and continuity conditions. The results in this paper are applied to a class of abstract semilinear evolution equations with noncompact semigroup in Banach spaces and the initial value problems for nonlinear second-order integro-differential equations of mixed type in Banach spaces. The results obtained here improve and generalize many known results.     

非局部反应扩散方程奇摄动问题

本文研究了一类具有非局部初始条件的奇摄动反应扩散问题．在适当的条件下，利用比较定理讨论了问题解的渐近性态．     

具有非局部边界条件的奇摄动反应扩散问题

本文研究了一类具有非局部边界条件的奇摄动反应扩散初始边值问题．在适当的条件下，利用比较定理讨论了问题解的渐近性态．     

Global solutions of initial value problems for nonlinear second-order impulsive integro-differential equations of mixed type in Banach spaces

In this paper, we develop a theorem for the existence of global solutions of an initial value problems for a class of second-order impulsive integro-differential equations of mixed type in a real Banach space. The results obtained are the generalizations and improvements of various recent results. As an application of the theorem, the existence of global solutions of two mixed boundary value problems for two classes of fourth-order impulsive differential equations are established.     

On the exact solutions for initial value problems of second-order differential equations

In this paper, the solutions of initial value problems for a class of second-order linear differential equations are obtained in the exact form by writing the equations in the general operator form and finding an inverse differential operator for this general operator form.     

Well-posedness of initial value problems for singular parabolic equations

We study well-posedness of initial value problems for a class of singular quasilinear parabolic equations in one space dimension. Simple conditions for well-posedness in the space of bounded nonnegative solutions are given, which involve boundedness of solutions of some related linear stationary problems. By a suitable change of unknown, the above results can be applied to classical initial-boundary value problems for parabolic equations with singular coefficients, as the heat equation with inverse square potential.     

ASYMPTOTIC BEHAVIOR OF SOLUTION FOR A CLASS OF REACTION DIFFUSION EQUATIONS

A class of initial boundary value problems for the reaction diffusion equations are considered. The asymptotic behavior of solution for the problem is obtained using the theory of differential inequality.     

On Warner's algorithm for the solution of boundary-value problems for ordinary differential equations

The paper discusses the solution of boundary-value problems for ordinary differential equations by Warner's algorithm. This shooting algorithm requires that only the original system of differential equations is solved once in each iteration, while the initial conditions for a new iteration are evaluated from a matrix equation. Numerical analysis performed shows that the algorithm converges even for very bad starting values of the unknown initial conditions and that the number of iterations is small and weakly dependent on the starting point. Based on this algorithm, a general subroutine can be realized for the solution of a large class of boundary-value problems.