A COMPLETE EXPRESSION OF THE ASYMPTOTIC SOLUTION OF DIFFERENTIAL EQUATION WITH A∩-TH ORDER TURNING POINT

A second order linear ordinary differential equation has been studied, and the complete expresson, of the formal uniformly valid asymptotic solutions to the equation near turning point is obtained by using extended Airy function.     

双参数地基上板弯曲问题的边界积分方程

本文应用广义函数的Fourrier积分变换导出了双参数地基上板弯曲问题的基本解,并将基本解展成一致收敛的级数形式.在此基础上,应用广义Rayleigh-Green公式建立了适用于任意形状、任意边界条件情形的两个边界积分方程,为边界元法在这一问题中的应用提供了理论基础.     

Positive solutions for (n−1,1) three-point boundary value problems with coefficient that changes sign

In this paper, we establish existence results for positive solutions for the (n−1,1) three-point boundary value problems consisting of the equation

     

三阶非线性时滞差分方程解的渐近性

研究了一类三阶非线性变滞量差分方程解的渐近性,给出了该类方程的非振动解当n→+∞时渐近趋于零或趋于某有限数值的几个充分条件.     

θ-Fuzzy关系方程的分解与求解

在有限论域上首先给出θ-Fuzzy关系方程的分解，然后针对NR-蕴涵θ，探讨θ-Fuzzy关系方程的求解问题，基于解矩阵给出解的存在性的几个新判据，并在解集非空时，证明θ-Fuzzy关系方程的每一个解都存在一个极大解。     

多目标规划的鞍点准则

本文给出多目标规划有效解适应鞍点准则的一个新的判别法 ,它不使用凸性的几何术语及凸分析中的概念。最后给出单目标规划的一个相应的判别法     

On periodic solutions of nonlinear integral equations modelling infectious disease on measure chain

The modelling of the spread of infectious disease is carried out for time t on a measure chain T. Our approach unifies the continuous case and the discrete case . The model is described by the integral equation

where x(t) represents the proportion of the population infected at time t, f(t,x(t)) denotes the proportion of the population newly infected per unit time, and τ is the length of time an individual remains infectious. Using the measure chain calculus, we shall develop criteria for the existence of a nontrivial and nonnegative periodic solution for the modelling equation. The criteria can be implemented numerically, for this we shall give an algorithm as well as illustrative examples.     

热爆炸临界参数的数值解法

本文提出的热爆炸临界参数的数值解法是一种变分方法.这种方法依据的是文献[1]给出的热爆炸临界参数的一个变分原理。数值计算的结果表明,这种方法是一种简便、经济而又精确度较高的方法。     

分子聚集溶液理论及其应用

本文应用经典热力学和分子热力学方法建立了分子聚集溶液理论。该理论具有通用性；它不仅适用于非电解质溶液，而且也可应用于电解质溶液。另外，溶液的分子聚集度参数与组分浓度的相关性规律还可用来描述电解质溶液的传递性质。     

具超前变元的二阶微分方程三点边值问题的正解

§ 1　 IntroductionRecently,certain three-point boundary value problems for nonlinear ordinarydifferential equations have been studied by many authors[1— 6] .However,few papers havebeen published on the same problems for nonlinear functional differential equations.In thispaper,we are concerned with the following second order differential equation with anadvanced argumentu″(t) +λa(t) f(u(h(t) ) ) =0 ,t∈ (0 ,1 ) (1 .1 )with the three-point boundary conditionsu(0 ) =0 ,αu(η) =u(1 ) ,(1 .2 )…