关于一类向量极值问题弱有效解的充分必要条件

本文研究带集合约束的向量极值问题。运用局部凸Hausdorff拓扑向量空间中广义次似凸映射的择一定理和其他一些结论，得到了关于集合约束向量极值问题弱有效解的几个充分必要条件．     

Some limit theorems for regenerative queues

We consider a single server queue with the interarrival times and the service times forming a regenerative sequence. This traffic class includes the standard models: iid, periodic, Markov modulated (e.g., BMAP model of Lucantoni [18]) and their superpositions. This class also includes the recently proposed traffic models in high speed networks, exhibiting long range dependence. Under minimal conditions we obtain the rates of convergence to stationary distributions, finiteness of stationary moments, various functional limit theorems and the continuity of stationary distributions and moments. We use the continuity results to obtain approximations for stationary distributions and moments of an MMPP/GI/1 queue where the modulating chain has a countable state space. We extend all our results to feed-forward networks where the external arrivals to each queue can be regenerative. In the end we show that the output process of a leaky bucket is regenerative if the input process is and hence our results extend to a queue with arrivals controlled by a leaky bucket. This revised version was published online in June 2006 with corrections to the Cover Date.     

A NOTE ON COMPARISON THEOREM OF TWO-STAGE ITERATIVE METHOD FOR HERMITIAN POSITIVE DEFINITE LINEAR SYSTEMS

We discuss two-stage iterative methods for the solution of linear system Ax = b, and give a new proof of the comparison theorems of two-stage iterative method for an Hermitian positive definite matrix. Meanwhile, we put forward two new versions of well known comparison theorem and apply them to some examples.     

Some Intersection Theorems and Minimax Inequalities

This paper proves some intersection theorems. The proofs are new in the sense that they do not require the finite intersection property. As an application, some of the Fan minimax inequalities are proved.     

Regularity Conditions for the Linear Separation of Sets

In this paper, we study the linear separation between a set and a convex cone. We introduce the concepts of regularity and total regularity of the separation with respect to a face of the cone and we give theorems characterizing them.     

高阶非线性中立型方程正解的渐近性及存在性

本文利用非线性分析中半序方法和增算子不动点定理，对高阶非线性中立型方程正解的渐近性进行了详细分类，并且给出了各种类型正解存在的充要条件和具体例子．     

Approximating spectral invariants of Harper operators on graphs II

We study Harper operators and the closely related discrete magnetic Laplacians (DML) on a graph with a free action of a discrete group, as defined by Sunada. The spectral density function of the DML is defined using the von Neumann trace associated with the free action of a discrete group on a graph. The main result in this paper states that when the group is amenable, the spectral density function is equal to the integrated density of states of the DML that is defined using either Dirichlet or Neumann boundary conditions. This establishes the main conjecture in a paper by Mathai and Yates. The result is generalized to other self adjoint operators with finite propagation speed.

     

New Saddle Point Theorem Beyond Topological Vector Spaces

The purpose of this note is to prove a new topological saddle-point theorem, which in turn includes classical saddle-point theorems such as the Sion minimax theorem and others in topological vector spaces as special cases.     

具有可积伸张同胚的边界扩张

研究了具有可积伸张的同胚，证明了在一定条件下这类同胚可以连续扩张到边界．     

非自治非光滑系统的Matrosov稳定性定理

本文在一般Filippov解意义下研究了一类非自治非光滑切换系统的Matrosov稳定性定理,并作为推论,修正了相关文献中关于非光滑系统稳定性的一个结果,最后给出了在一类带有不连续摩擦项的力学系统的跟踪问题中的应用．