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1.
证明了如下结果:设g∶H→H,C H是非空开的g-凸集,g(C)是凸集,f是C上的上半连续函数且存在α∈(0,1),使得f(αg(x)+(1-α)g(y))m ax{f。g(x),f。g(y)},x,y∈C,则f为C上的g-拟凸函数.  相似文献   

2.
本文提出了中点拟凸函数的概念,在可测函数空间中,给出了中点拟凸函数拟凸的若干个充分条件.  相似文献   

3.
Yang et al gave some criteria of prequasi-invex functions,semistrictly prequasi-invex functions and strictly prequasi-invex functions in 2001 ,under a certain set of conditions. In this note,some of these conditions can be weakened to get the same results ,and another simplified proof for a criterion of prequasi-invex functions established under the condition of lower semicontinuity is given.  相似文献   

4.
有理插值问题存在性的一个判别准则   总被引:10,自引:4,他引:10  
1引言我们知道,多项式Lagrange插值是适定的[1,2],但有理插值函数却未必存在[8,3].并且到目前为止,也没有类似于多项式Lagrange插值的能够揭示插值结构的显式插值公式.不过有理插值已有许多算法,比如Stoer算法,Thiele倒差商算法,Salzer算法以及Wuytack算法等等,见[8,4,5,6].本文为寻求尽可能接近显式的插值公式,进而揭示有理插值问题的内在结构,得到了有理插值函数存在的一个充要条件,同时也给出了有理插值函数的一种表现形式,参见[11].本文约定,所有矩阵…  相似文献   

5.
上半连续函数的拟凸性   总被引:15,自引:0,他引:15  
在这篇文章里,证明了下述结果:设是非空开凸集,f是C上的上半连续函数且存在α∈(0,1),使得f(αx+(1-α)y≤max{f(x),f(y)},∨x》,y∈C则f为C上的拟凸函数.  相似文献   

6.
在更弱的连续假设下研究集合A_(x,y)={λ∈[0,1]|f(λE(x)+(1-λ)E(y))≤λf(E(x))+(1-λ)f(E(y))}和集合A′_(x,y)={λ∈[0,1]|f(λE(x)+(1-λ)E(y))≤max{f(E(x)),f(E(y))}}的稠密性、闭性、(弱)近似凸性,得到E-凸函数和E-拟凸函数的等价条件.  相似文献   

7.
张晓岚 《数学季刊》1997,12(3):95-100
51.PreliminaryLetXbeaset.Througho11ttl1lspaperweshalldenoteby2xthefaruilyofallsubsetsofX,by(X)thefamilyofallnoneruptyfinitesuhsetsof'X.lfXlsasul,setofavectorspace,co(X)denotestheconvexhu1lofX.IfXisatopologicalspaceandA=X,thenwedenotebyintx(A)theil1teriorofAinXandc.l.(A)theclosureofAinXrespectively.Definitionl.1LetXandYl)etoI3ologicalspacesandT:X-2"isaset-vail1edmapping.(i)Tissaidtobeuppersemicontin\1ous(resp.lowersemicontinuo1Js)atxo6X,ifforeachopensetGinYwithG=T(x,)(resI3.Gn7'(x,…  相似文献   

8.
拓扑向量空间中锥半连续性与锥拟凸映射   总被引:2,自引:0,他引:2  
对于拓扑向量空间中的几个锥拟凸映射,讨论了它们之间的若干关系,同时,对锥半连续及锥上半连续映射的锥拟凸性给出了一些结果。  相似文献   

9.
丰建文  陈士华 《数学杂志》2000,20(4):465-468
分支理论中方程x″ g(x)=0的周期映射的单调性是非常重要的,本文通过一系列积分变换得得到了方程x″ g(x)=0的周期映射的积分形公式,并利用它给出了判别周期映射单调性的一个判别准则。  相似文献   

10.
基于空间仿射变换能够保持点与直线的结合性这一性质,引入满秩坐标变换作为工具,扩展了锥面判别定理的应用范围.  相似文献   

11.
A function defined on a locally convex space is called evenly quasiconvex if its level sets are intersections of families of open half-spaces. Furthermore, if the closures of these open halfspaces do not contain the origin, then the function is called R-evenly quasiconvex. In this note, R-evenly quasiconvex functions are characterized as those evenly-quasiconvex functions that satisfy a certain simple relation with their lower semicontinuous hulls.  相似文献   

12.
Let F be a family of meromorphic functions in D,and let Ψ(≠0) be a meromorphic function in D all of whose poles are simple.Suppose that,for each f ∈F,f≠0 in D.If for each pair of functions {f,g}(?) F,f' and g' share Ψ in D,then F is normal in D.  相似文献   

13.
Semicontinuity and Quasiconvex Functions   总被引:11,自引:0,他引:11  
Criteria are derived for quasiconvex functions under lower semicontinuity and upper semicontinuity conditions. The results thus obtained generalize earlier results for convex functions. We also give new conditions under which a given function is r-convex in the sense given by Avriel.  相似文献   

14.
We introduce the notion of variational (semi-) strict quasimonotonicity for a multivalued operator T  : XX * relative to a nonempty subset A of X which is not necessarily included in the domain of T. We use this notion to characterize the subdifferentials of continuous (semi-) strictly quasiconvex functions. The proposed definition is a relaxation of the standard definition of (semi-) strict quasimonotonicity, the latter being appropriate only for operators with nonempty values. Thus, the derived results are extensions to the continuous case of the corresponding results for locally Lipschitz functions.  相似文献   

15.
Extending the approach initiated in Aussel and Hadjisavvas (SIAM J. Optim. 16:358–367, 2005) and Aussel and Ye (Optimization 55:433–457, 2006), we obtain the existence of a local minimizer of a quasiconvex function on the locally finite union of closed convex subsets of a Banach space. We apply the existence result to some difficult nonconvex optimization problems such as the disjunctive programming problem and the bilevel programming problem. Dedicated to Jean-Pierre Crouzeix on the occasion of his 65th birthday. The authors thank two anonymous referees for careful reading of the paper and helpful suggestions. The research of the second author was partially supported by NSERC/Canada.  相似文献   

16.
陈省江  许爱珠 《数学研究》2012,45(2):188-191,212
改进Heittokangas等最近获得的涉及亚纯函数与其平移函数唯一性的一个结果[J.Heit-tokangas,R.Korhonen,I.Laine,J.Rieppo and J.Zhang,Value sharing results for shifts of mero-morphic function and sufficient conditions for periodicity,J.Math.Anal.Appl.,355(2009):352-363].  相似文献   

17.
New concepts of semistrict quasimonotonicity and strict quasimonotonicity for multivalued maps are introduced. It is shown that a locally Lipschitz map is (semi)strictly quasiconvex if and only if its Clarke subdifferential is (semi)strictly quasimonotone. Finally, an existence result for the corresponding variational inequality problem is obtained.  相似文献   

18.
The global solutions of the problem of maximizing a convex function on a convex set were characterized by several authors using the Fenchel (approximate) subdifferential. When the objective function is quasiconvex it was considered the differentiable case or used the Clarke subdifferential. The aim of the present paper is to give necessary and sufficient optimality conditions using several subdifferentials adequate for quasiconvex functions. In this way we recover almost all the previous results related to such global maximization problems with simple proofs.  相似文献   

19.
化简Fuzzy逻辑函数直接方法的注记   总被引:1,自引:0,他引:1  
本文改进了[1]给出的化简Fuzzy逻辑函数的方法,首先给出广义互补项的概念,并应用它证明可删去顶的充要条件,然后给出了不满足定理条件的问题解决办法,从而得到一种既方便又能将Fuzzy逻辑函数化到最简的办法.  相似文献   

20.
1.IntroductionLetZdenotetheclassoffunctiollsoftheformf(z)=f Z7=.a.z"thatareregulaxinthepunctuxeddiskE={z:0相似文献   

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