关于E-凸函数和E-凸规划的错误结论

最近Youness在文[1]建立了一类E-凸函数和一类E-凸规划,并分析和给出了他们的主要性质。本文通过6个反例说明文[1]关于E-凸函数和E-凸规划的大部分结论是错误的。     

广义分式规划中的鞍点存在性定理

利用向量值广义凸函数等概念,讨论了一类不可微广义分布式规划的Lagrange函数,在适当条件下,证明了广义分式规划中的鞍点存在性定理。     

(p,r)-不变凸函数规划问题的鞍点定理

本文首先介绍了一个广义Lagrange向量函数L(x,u),并利用一类新的广义 凸函数:(p,r)——不变凸函数讨论了多目标分式规划问题的鞍点最优性条件．     

具有(F,α,ε)-G凸的分式半无限规划问题的ε-最优性

首次引入了（F,α,ε）-G凸函数,（F,α,ε）-G拟凸函数和（F,α,ε）-G伪凸函数等概念,对已有的凸函数进行了推广,研究了涉及这类函数的一类分式半无限规划的ε-最优性条件,得到了一些有意义的结果．这些结果不仅是现有某些结果的推广,而且为诸如资源分配,投资组合等问题的研究提供了依据,也为理论上研究分式规划提供了参考．     

一种新广义凸多目标分式规划的最优性充分条件

提出了（F,α,ρ,θ）-b-凸函数的概念,它是一类新的广义凸函数,并给出了这类广义凸函数的性质.在此基础上,讨论了目标函数和约束函数均为（F,α,ρ,θ）-b-凸函数的多目标分式规划,利用广义K-T条件,得到了这类多目标规划有效解和弱有效解的几个充分条件,推广了已有文献的相关结果.     

关于凸函数的双参数平均不等式

本文利用二重积分证明了凸函数的双参数平均不等式,并给出了它的几个推论从而推广和加强了文[3]的定理。     

非线性分式规划对偶模型的比较

分式规划的对偶理论,有许多研究成果。特别是对线性分式规划,建立了各种各样的对偶模型。文章[1]对这些对偶模型之间的内在联系,进行了综合比较。文章[2]、[3]、[4]对如下一类非线性分式规划(P)的对偶理论进行了详细的讨论,并且分别建立了(P)的两种不同形式的对偶模型。     

显凸函数的一些性质

最近,薛声家教授在文[1]中提出了一种新的凸性概念——显凸函数。它是比严格凸函数弱且又不同于凸函数的一类新凸性。文[1]对它已作了初步讨论。本文继续的工作,给出显凸函数的一些性质。定义称f是凸集S(?)R~n上的显凸函数,若对任意x,y∈S,f(x)≠f(y),有首先,给出显凸函数的一个特征性质,它类似于凸函数的一个已知性质。     

巧求一类分式函数的最小值

文[1]给出了条件为x+y=1(或x+y+z=1)的分式函数最值问题的“代入法”,文[2]对此进行补充,给出简单解法及最值k的确定方法,但他们的思路与解法依然曲折繁琐,文[2]刻意追求最值k更无必要,其实,只要把1=x+y(或1=x+y+z)直接代入分式函数的分子,然后对分式函数适当分拆,利用算术平均值不等式构造出“积为定值”,最值k就自然迅速直接地浮出水面了.更重要的是,此方法     

多目标分式规划的两种新对偶形式

§1.引言和引理 在[1]和[2]中,C.Singh和林锉云曾分别研究了多目标分式规划的对偶问题,本文则给出多目标分式规划的另外两种新的对偶形式。这两种对偶规划和R.Jagannathan以及C.Bector关于非线性规划的对偶理论有关。最后,我们还讨论了所研究的两种多目标分式对偶规划之间的相互关系。 考虑多目标分式规划     

Uniform universal covers of uniform spaces

We develop a generalized covering space theory for a class of uniform spaces called coverable spaces. Coverable spaces include all geodesic metric spaces, connected and locally pathwise connected compact topological spaces, in particular Peano continua, as well as more pathological spaces like the topologist's sine curve. The uniform universal cover of a coverable space is a kind of generalized cover with universal and lifting properties in the category of uniform spaces and uniformly continuous mappings. Associated with the uniform universal cover is a functorial uniform space invariant called the deck group, which is related to the classical fundamental group by a natural homomorphism. We obtain some specific results for one-dimensional spaces.     

Connectedness in Metric Frames

A new metric diameter for a locally connected metric frame is constructed which is finer than the original one. Amongst other results, this construction allows a proof that the category of uniformly locally connected metric frames and uniform frame maps is reflective in the category of locally connected metric frames and uniform frame maps. Mathematics Subject Classification (2000) 54A05.     

Quasi-asymptotic contractions,set-valued dynamic systems,uniqueness of endpoints and generalized pseudodistances in uniform spaces

For set-valued dynamic systems in uniform spaces we introduce the concept of quasi-asymptotic contractions with respect to some generalized pseudodistances, describe a method which we use to establish general conditions guaranteeing the existence and uniqueness of endpoints (stationary points) of these contractions and exhibit conditions such that for each starting point each generalized sequence of iterations (in particular, each dynamic process) converges and the limit is an endpoint. The definition, result, ideas and techniques are new for set-valued dynamic systems in uniform, locally convex and metric spaces and even for single-valued maps.     

Solutions of system of generalized vector quasi-equilibrium problems in locally G-convex uniform spaces

In this paper we establish a collectively fixed point theorem and an equilibrium existence theorem for generalized games in product locally G-convex uniform spaces. As applications, some new existence theorems of solutions for the system of generalized vector quasi-equilibrium problems are derived in product locally G-convex uniform spaces. These theorems are new and generalize some known results in the literature.     

Endpoint theory for set-valued nonlinear asymptotic contractions with respect to generalized pseudodistances in uniform spaces

In uniform spaces, inspired by ideas of Banach, Tarafdar and Yuan, we introduce the concepts of generalized pseudodistances and generalized gauge maps, for set-valued dynamic systems we define various nonlinear asymptotic contractions and contractions with respect to these pseudodistances and gauges, provide conditions on the iterates of these set-valued dynamic systems and present a method which is useful for establishing conditions guaranteeing the existence and uniqueness of endpoints (stationary points) of these set-valued dynamic systems and conditions that each generalized sequence of iterations (in particular, each dynamic process) converges and the limit of a generalized sequence of iterations is an endpoint. The definitions, the results and the method are new for set-valued dynamic systems in uniform, locally convex and metric spaces and even for single-valued maps. The paper includes a number of various examples which show a fundamental difference between our results and those existing in the literature.     

Optimality conditions and duality on approximate solutions in vector optimization with arcwise connectivity

In this paper a new class of generalized vector-valued arcwise connected functions, termed sub-arcwise connected functions, is introduced. The properties of sub-arcwise connected functions are derived. The approximate quasi efficient solutions of vector optimization problems are studied, and the necessary and sufficient optimality conditions are obtained under the assumption of arcwise connectivity. An approximate Mond-Weir type dual problem is formulated and the duality theorems are established.     

一类非光滑多目标半无限规划的最优性条件

利用K-方向导数,给出了一类存在性更为广泛的广义凸函数.即广义一致K-（F,α,ρ,d）-I型凸函数,进而讨论了涉及这些新广义凸性的一类多目标半无限规划的最优性条件。     

Uniformly locally connected uniform <Emphasis Type="Italic">σ</Emphasis>-frames

We introduce and study the concept of a uniformly locally connected uniform σ-frame. The uniformly locally connected reflection of a locally connected uniform σ-frame is constructed.      

Local Connectedness Made Uniform

The uniformly locally connected reflection for a locally connected uniform frame is constructed. Applications of this construction to the theory of locally connected completely regular frames are given. One such application is that if a completely regular frame is locally connected and pseudocompact then every compactification of it is locally connected.     

The uniqueness of endpoints for set-valued dynamical systems of contractions of Meir–Keeler type in uniform spaces

In this paper, the concept of the set-valued dynamical systems of contractions of Meir–Keeler type in uniform spaces is introduced and conditions guaranteeing the existence and uniqueness of endpoints of these contractions and the convergence to these endpoints of all generalized sequences of iterations of these contractions are established. The definition and the result presented here are new for set-valued dynamical systems in uniform, locally convex and metric spaces and even for single-valued maps. Examples show a fundamental difference between our result and the well-known ones.