求解对数切比雪夫逼近问题的原对偶内点算法

文章对对数切比雪夫逼近问题在半正定规划框架下给出了最优性条件 ,并在此基础上构建了原对偶内点算法 ,最后给出了二阶收敛性     

STRONG APPROXIMATION FOR PERTURBED EMPIRICAL PROCESSES

ＳＴＲＯＮＧＡＰＰＲＯＸＩＭＡＴＩＯＮＦＯＲＰＥＲＴＵＲＢＥＤＥＭＰＩＲＩＣＡＬＰＲＯＣＥＳＳＥＳ￥ＺＨＯＵＹｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＰｒｏｂａｂｉｌｉｔｙａｎｄＳｔａｔｉｓｔｉｃｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７...     

THERMODYNAMIC PROPERTIES OF LADDER-LIKE HEISENBERG SYSTEM

By combining the cumulant expansion method with the double-chain approximation , we study thermodynamic properties of ladder-like He isenberg system. We find the interaction between interchains has different effect in high and low temperature.     

度量空间中的联合最佳逼近

本在度量空间中讨论了联合最佳逼近性，得到了闭球的凸性与凸集的联合最佳逼近性的关系。     

一类S.N.Bernstein型插值过程的最佳一致逼近

进一步研究了第三型S.N.Bernstein插值过程，用一种全新的方法构造了一个算子An(f;r,x)，它对于有任意阶连续导数的f(x)∈C[-1,1]^1,(0≤l≤r-1)都一致收敛，并且得到了算子An(f;r,x)的最佳收敛阶。     

广义Abel平均在实H~p(R~n)(0

张严 《北京师范大学学报(自然科学版)》1988,(2)

ERROR ESTIMATION OF THE APPROXIMATION ALGORITHM FOR THE WINDY POSTMAN PROBLEM

If we restrict the postman to traversing each edge at most twice in the windypostman problem (WPP), we will get a new problem: 2WPP. An approximation algorithmhas been posed by M. Guan for the WPP. In the present paper, we improve the estimatederror given by M. Guan and show that we can estimate the error for the 2WPP by findinga minimum cost circulation. We also pose a new sufficient condition for the equivalencebetween WPP and 2WPP, which can be checked in polynomial time steps.     

最佳逼近常数的上界估计

本文改进了函数构造论中著名的Джексона定理的结果。