Generalized second-order characterizations of convex functions

We introduce a second-order upper Dini-directional derivative and obtain a second-order characterization for a continuously Gâteaux differentiable function to be a convex function.This research was done under the supervision of Dr. V. Jeyakumar whose helpful guidance and valuable suggestions are much appreciated. The author is thankful to the referee for providing a simplication of the original proof of Theorem 2.1.     

凸函数的支撑凸集及其集映射

本文研究了线性空间中凸函数的支撑泛函存在性以及支撑泛函的数值域,利用子空间中支撑泛函延拓的方法,构造出在线性空间任意点的支撑泛函,确定在同一支撑点上支撑泛函的数值域,从而得到支撑泛函具有唯一性的充分必要条件,最后对支撑凸集到支撑泛函集的集映射进行讨论.     

Measure of Non-Radon–Nikodym Property and Differentiability of Convex Functions on Banach Spaces

We introduce and discuss measure of non-Radon–Nikodym property to investigate differentiability of continuous convex functions on Banach spaces. Using this new concept, we establish some results about Asplund spaces and generic Fréchet differentiability of continuous convex functions on non-Asplund spaces.Mathematics Subject Classifications (2000) 46B22, 49J50, 49J53.     

The Berezin and Garding Inequalities

Let ϕ be a convex function on ℂ, let ℒ(σ) be a pseudodifferential operator with symbol σ, let Λ_σ be the set of its eigenvalues, and let m(λ) be the multiplicity of an eigenvalue λ ∈ Λ_σ. Under certain natural assumptions about properties of pseudodifferential operators, we prove that \(\sum {_{\lambda \in \Lambda _\sigma } m(\lambda )} \varphi (\lambda ) \leqslant \operatorname{Tr} L(\varphi (\sigma )) + R\), where R is an error term of the same order as the remainder term in the Garding inequality.     

一类加强不等式的推广

本文给出了 n个正数 x1 ,x2 ,… ,xn 的如下不等式 :∏nk=1( xαk+x-αk )≥ ( Aαn( x) +A-αn ( x) ) n ,每个 xk≤ xα,∏nk=1( xαk+x-αk )≤ ( Aαn( x) +A-αn ( x) ) n ,每个 xk≥ e.其中 α>0 ,xα=[4α2 +1 +2 α]12α ,常数 e=2 .71 81 82 81 8… ,An( x) =1n∑nk=1xk.     

Banach空间的p— Asplund 伴随空间

我们称一个定义在Banach空间E上的连续凸函数f具有Frechet可微性质（FDP），如果E上的每个实值凸函数g≤f均在E一个稠密的Gδ－子集上Frechet可微。本文主要证明了：对任何Banach空间E，均存在一个局部凸相容拓扑p使得1）（E，p)是Hausdorff局部凸空间；2） E上的每个范数连续具有FDP的凸函数均是p－连续的；3）每个p-连续的凸函数均具有FDP ；4）p等价某个范数拓扑当且仅不E是Asplund空间。     

求解交通均衡配流问题的新算法

给出了一个求解交通均衡配流问题的新算法,证明了新算法的收敛性,并在小型交通网络上进行了初步的数值试验.     

一类新的伪凸函数

在实践域上定义并讨论了γ－伪凸函数的性质，利用γ－次可微的定义，讨论了新型函数类的极值性质，指出通常伪凸函数是γ－伪凸的。     

New variants of the generalized level method for minimization of convex nondifferentiable functions taking infinite values

New variants of the generalized level method for minimization of convex Lipschitz functions on a compact set with a nonempty interior are proposed. These variants include the well-known generalized and classical level methods. For the new variants, an estimate of the convergence rate is found, including the variants in which the auxiliary problems are solved approximately.     

两个凸函数单调平均不等式的改进

改进了有关凹函数和凸函数的算术平均值单调性的某些已知结论.作为应用,加强了M inc-Sathre不等式和A lzer不等式.