Star-shaped Differentiable Functions and Star-shaped Differentials

Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defined. Formulas for star-shaped differential of a pointwise maximum and a pointwise minimum of a finite number of directionally differentiable functions, and a composite of two directionaUy differentiable functions are derived. Furthermore, the mean-value theorem for a directionaUy differentiable function is demonstrated.     

无界区间上脉冲发展微分包含解的存在性

本文讨论了无界区间上脉冲发展微分包含解的存在性.通过使用一个新的Leray-Schauder型的非线性多值二择一定理,在适当的条件下,建立了这类问题解存在的充分条件.     

广义稠密随机交集图的度分布(英文)

广义随机交集图是一类重要的随机图模型,它是E-R随机图的变种,被广泛用于复杂社会网络的研究中.本文研究了在顶点度的期望趋于无穷的情况下,广义随机交集图的度分布.我们对二项模型给出了中心极限定理,并且对一致模型给出了极限定理.     

平面向量基本定理的一个推论的应用

平面向量是高中数学的一个重要考点．特别是对平面向量基本定理的应用更是常考的内容．但是,将平面向量中的平面向量基本定理加以推广,我们还可以得到如下命题：     

解三角形的三种转化思路方法

解答一些解三角形的题目,常常需要运用正弦定理、余弦定理及三角形内角和定理等知识,将已知条件中的边的关系式转化为角的三角函数关系式或将角的三角函数关系式转化为边的关系式,下面联系具体例题讲常用的三种转化思路方法．     

分组ρ~*-混合随机场的强极限定理

利用求和法,在矩条件下,给出分组ρ*-混合随机场的强极限定理。它是经典结果的推广。     

一类带位势非线性热方程解的不存在性定理

研究与向量场有关的非线性次椭圆热方程.通过选取合适的测试函数,应用反证法证明了与之相关的初边值问题解的不存在性定理,将欧式空间及Heisenberg群上的结果推广至满足H（o）rmander有限秩条件的光滑向量场.     

Stability for impulsive functional differential equations with infinite delays

In this paper, some theorems of uniform stability and uniform asymptotic stability for impulsive functional differential equations with infinite delay are proved by using Lyapunov functionals and Razumikhin techniques. An example is also proved at the end to illustrate the application of the obtained results.     

Existence of sign-changing solutions for the p-Laplacian equation from linking type theorem

In this paper, the existence of sign-changing solutions for p-Laplacian equation is obtained via a new linking theorem.     

Weak convergence theorem for Lipschizian pseudocontraction semigroups in Banach spaces

The purpose of this paper is to study the weak convergence problems of the irnplicity iteration process for Lipschitzian pseudocontraction semigroups in general Banach spaces. The results presented in this paper extend and improve the corresponding results of Zhou [Nonlinear Anal., 68, 2977-2983 （2008）], Chen, et ah [J. Math. Anal. Appl., 314, 701 709 （2006）], Xu and Ori [Numer. Funct. Anal. Optim, 22, 767-773 （2001）] and Osilike [J. Math. Anal. Appl., 294, 73-81 （2004）]. Keywords