关于运输问题最优解的进一步讨论

首先给出了运输问题最优解的相关概念,将最优解扩展到广义范畴,提出狭义多重最优解和广义多重最优解的概念及其区别.然后给出了惟一最优解、多重最优解、广义有限多重最优解、广义无限多重最优解的判定定理及其证明过程.最后推导出了狭义有限多重最优解个数下限和广义有限多重最优解个数上限的计算公式,并举例验证了结论的正确性.     

Banach空间超线性算子方程的多解定理及其应用

本文利用两对平行上下解,讨论了一类超线性算子方程的多解的存在性,得到了六解定理和七解定理.文中所得结果本质地改进了著名的Amann三解定理.作为应用,考虑了二阶微分方程组,得到了新的结论.     

两个非线性发展方程精确解析解的研究

对齐次平衡法进行了改进并将其应用于两个非线性发展方程中,通过一些新的假设,获得了若干精确解析解,这些解包含王和张的结论及其它新类型的解析解,如果理分式解和周期解,这种方法也可以应用于求解更多的非线性偏微分方程。     

关于两个线性方程组同解条件的再思考

首先给出了两个线性方程组Ax=c及Bx=d的解与解之间的关系,通过对两个方程组有公共解的条件的研究,从而给出了两个方程组有同解的充分必要条件.根据所得结论,最后给出了两个线性方程组是否有同解的判别方法以及同解的求解方法.     

关于修正迭代解与钱氏摄动解的关系

本文给出了修正迭代解高阶解的解析特征关系式,从而使解析电算法的计算量得以减少.随后通过论证,得到修正迭代解与钱氏解的关系和这两种方法的收敛域相同的结论.     

广义Davey-Stewartson方程组的整体解及自相似解

本文研究Dalvey-Stewartson方程组的整体解与自相似解的存在性.首先,运用Ba- nach不动点定理得到一个关于解整体存在性的一般性定理,然后把一类特殊的初始值用到该存在性结果上去从而得到自相似解存在的结论.     

时滞合作扩散系统的波前解

本文建立了两种群时滞合作系统波前解的存在性定理，扩展了单种群生物模型的结论．     

矩阵方程AXB=D解的研究

给出了矩阵方程AXB=D相容的又一充要条件,同时讨论它的极小范数解、最小二乘解和极小范数最小二乘解,推广了文献[1]和[3]的结论.     

一类高维Riccati方程的解

研究了一类具有指数型二分性的高维Riccati方程存在有界解、周期解的充分条件,得到一些结论。     

约束半环诱导的赋值代数的轮廓解及其算法

本文研究了约束半环所诱导的赋值代数的轮廓解及其算法的问题.利用约束半环的性质,以及基于记忆约束半环赋值的方法,获得了约束半环所诱导的赋值代数的轮廓解的概念,性质以及算法的相关结论,推广了文献[2]关于全序幂等半环诱导的赋值代数的轮廓解的结果.     

双函数法及一类非线性发展方程的精确行波解

给出一种求解非线性发展方程精确行波解的新方法：双函数法。使用此方法，获得了一类非线性发展方程的许多精确行波解，其中包括孤波解和周期解，推广了文献用其它方法取得的结果，同时还获得了许多新的弧波解和周期解，借助于Mathemat-ica，此方法能部分地在计算机上实现。     

一类非线性演化方程新的显式行波解

借助Mathematica软件和吴方法,采用双曲函数法,获得了一类非线性演化方程u_tt+au_xx+bu+cu2+du3=0的多组行波解,其中包括周期解与孤子解.这种方法也适用于其他非线性方程或方程组.     

Exact explicit traveling wave solutions for two nonlinear Schrödinger type equations

The traveling wave solutions of the generalized nonlinear derivative Schrödinger equation and the high-order dispersive nonlinear Schrödinger equation are studied by using the approach of dynamical systems and the theory of bifurcations. With the aid of Maple, all bifurcations and phase portraits in the parametric space are obtained. All possible explicit parametric representations of the bounded traveling wave solutions (solitary wave solutions, kink and anti-kink wave solutions and periodic wave solutions) are given.     

非线性演化方程显式精确解的新算法

本文给出了一种求解非线性演化方程的新算法 .将这种算法运用于变形浅水波方程 ,获得了八组显式精确解 ,其中包括新的孤波解和周期解 .借助于 Mathematica软件 ,这种算法能够在 Computer上实现 .     

Dynamical understanding of loop soliton solution for several nonlinear wave equations

It has been found that some nonlinear wave equations have one-loop soliton solutions. What is the dynamical behavior of the so-called one-loop soliton solution? To answer this question, the travelling wave solutions for four nonlinear wave equations are discussed. Exact explicit parametric representations of some special travelling wave solutions are given. The results of this paper show that a loop solution consists of three different breaking travelling wave solutions. It is not one real loop soliton travelling wave solution.     

Direct search for exact solutions to the nonlinear Schrödinger equation

A five-dimensional symmetry algebra consisting of Lie point symmetries is firstly computed for the nonlinear Schrödinger equation, which, together with a reflection invariance, generates two five-parameter solution groups. Three ansätze of transformations are secondly analyzed and used to construct exact solutions to the nonlinear Schrödinger equation. Various examples of exact solutions with constant, trigonometric function type, exponential function type and rational function amplitude are given upon careful analysis. A bifurcation phenomenon in the nonlinear Schrödinger equation is clearly exhibited during the solution process.     

Bifurcations and exact traveling wave solutions of the equivalent complex short-pulse equations

In this paper, we study the traveling wave solutions for a complex short-pulse equation of both focusing and defocusing types, which governs the propagation of ultrashort pulses in nonlinear optical fibers. It can be viewed as an analog of the nonlinear Schrodinger (NLS) equation in the ultrashort-pulse regime. The corresponding traveling wave systems of the equivalent complex short-pulse equations are two singular planar dynamical systems with four singular straight lines. By using the method of dynamical systems, bifurcation diagrams and explicit exact parametric representations of the solutions are given, including solitary wave solution, periodic wave solution, peakon solution, periodic peakon solution and compacton solution under different parameter conditions.     

Multiple periodic solutions for system of first-order differential equation

Sufficient conditions have been obtained for the existence of at least two non-negative periodic solutions to a system of first-order nonlinear functional differential equations. Applications to some ecological models are given.     

The improved Fan sub-equation method and its application to the SK equation

In this paper, many types of exact solutions of a first-order nonlinear ordinary differential equation called Fan sub-equation, is further investigated by using bifurcation method of dynamical systems. As a result, more types of exact solutions to Sawada-Kotera (SK) equation are obtained, which include more general soliton solutions, kink solutions, triangular function solutions, Jacobian elliptic function solutions with double periods and so on.