关于Sikkema─Bernstein算子的推广     

陈进 《江西教育学院学报》1994,(6)

本文引入算子Ｌｎ（ｆ；ｘ）并研究其收敛性及逼近阶。  相似文献   

Viscosity approximation methods with weakly contractive mappings for nonexpansive mappings     

WANG Ya-qin 《浙江大学学报(A卷英文版)》2007,8(10)

Let K be a closed convex subset of a real reflexive Banach space E, T:K→K be a nonexpansive mapping, and f:K→K be a fixed weakly contractive (may not be contractive) mapping. Then for any t∈(0, 1), let xt∈K be the unique fixed point of the weak contraction x tf(x) (1?t)Tx. If T has a fixed point and E admits a weakly sequentially continuous duality mapping from E to E*, then it is shown that {xt} converges to a fixed point of T as t→0. The results presented here improve and generalize the cor- responding results in (Xu, 2004).  相似文献   

周期函数的平均逼近与一致逼近的对偶关系     

文胜友 《韩山师范学院学报》1997,18(2):5-9

在周期卷积函数类的平均逼近与一致逼近中，对偶关系起着很重要的作用，本文给出了对偶关系成立的各种充分及必要条件。  相似文献   

基于非对称相似关系的粗集改进模型     

刘高峰  王淑玉 《唐山学院学报》2007,20(2):3-4

改进了基于非对称相似关系的粗集的上、下近似的定义,并从理论上证明了新定义的上、下近似比原来的更合理,并进一步用一个算例来验证。  相似文献   

Simultaneous perturbation stochastic approximation algorithm combined with neural network and fuzzy simulation     

宁玉富唐万生  郭长友 《天津大学学报(英文版)》2008,14(1):43-49

In order to solve three kinds of fuzzy programm model, fuzzy chance-constrained programming mode ng models, i.e. fuzzy expected value and fuzzy dependent-chance programming model, a simultaneous perturbation stochastic approximation algorithm is proposed by integrating neural network with fuzzy simulation. At first, fuzzy simulation is used to generate a set of input-output data. Then a neural network is trained according to the set. Finally, the trained neural network is embedded in simultaneous perturbation stochastic approximation algorithm. Simultaneous perturbation stochastic approximation algorithm is used to search the optimal solution. Two numerical examples are presented to illustrate the effectiveness of the proposed algorithm.  相似文献   

Hilbert空间内单调的李普希茨算子的一种逼近方法     

韩云旨 《保定师专学报》2000,13(2):8-10

证明了Chiduime定理对于Ishikawa迭代也成立。  相似文献   

一类修正的Bernstein算子的点态逼近估计     

连博勇  陈玲菊 《闽江学院学报》2013,34(2):13-15

利用经典的Bojanic-Cheng分解方法,结合分析技术,研究了修正的Bernstein算子对一类绝对连续函数的逼近,得到比较精确的收敛阶和渐近展开式.  相似文献   

Hermite插值算子在加权Lp范数下的导数逼近     

王鑫  崔然 《保定师专学报》2011,(3):19-23

讨论以第二类Chebyshev多项式的零点为插值结点组的Hermite插值算子在加权Lp范数下的导数逼近问题的一种特殊情况,得到利用最佳逼近的精确阶估计.  相似文献   

Converse result on Szász-type operators     

宋占杰 《天津大学学报(英文版)》2010,16(2):135-137

Szasz-type operators can be constructed by a Poisson process. The purpose of this paper is to derive the converse result in connection with Szasz-type operators by Steckin-Marchaud-type inequalities and new Ditzian modulus of continuity. The degree of approximation on deterministic signals is also given.  相似文献   

线性约束下广义中心对称矩阵扩充及其最佳逼近     

张华珍 《荆门职业技术学院学报》2010,25(5):39-43

文章讨论子矩阵约束下‖AX-Z‖2＋‖YHA-WH‖2=min的广义中心对称解及其最佳逼近,给出了解存在的充要条件及通解的表达式,并且给出了解集合中与给定矩阵的最佳逼近。  相似文献