广义平衡问题和渐近严格伪压缩映象的粘滞-投影方法

利用Meir-Keeler压缩映象,定义了一个关于广义平衡问题和渐近严格伪压缩映象的粘滞-投影方法,在Hilbert空间中建立逼近广义平衡问题的解和渐近严格伪压缩映象不动点的强收敛定理,并在收敛性分析中去掉了部分迭代控制条件和映象的渐近正则性等.     

严格渐近伪压缩映象隐迭代序列的收敛性

含有非扩张型映射的非线性算子方程的隐式迭代法,从2001年由H.K.Xu和R.G.Ori引入以来,已有许多学者进行了研究,得出了一些有意义的成果.最近M.O.Osilike对Browder-Petyshyn意义下的严格伪压缩映象的隐迭代过程,也做出了部分研究成果,但对严格渐近伪压缩映象未曾涉及.本文将主要研究Browder-Petyshyn意义下的严格渐近伪压缩映象的隐迭代过程.并讨论它们的收敛性问题.     

关于伪单调平衡问题和不动点问题的粘滞-次梯度方法

本文介绍了一个新的逼近伪单调平衡问题的解和广义渐近λ-严格伪压缩映象不动点的粘滞-次梯度方法,在Hilbert空间中建立了关于伪单调平衡问题和一簇广义渐近λ-严格伪压缩映象公共不动点的强收敛定理,并在收敛性分析中去掉了映象的一致Lipschitz连续性条件.     

赋范线性空间中渐近伪压缩映象的不动点迭代逼近

研究了赋范线性空间中渐近非扩张映象和渐近伪压缩映象不动点的迭代逼近问题,所得结果改进和推广了已有的一些结果.     

无限族严格渐近伪压缩映象隐迭代程序的强收敛定理

在Banach空间框架下,对无限族的严格渐近伪压缩映象和无限族的非扩张映象引入了一类新的隐迭代程序,并在适当的条件下,证明了该迭代程序强收敛于这两族映象的公共不动点.结果是新的,它推广和改进了一些人的最新结果.     

Banach空间中非线性Φ-伪压缩映象不动点的迭代逼近

本文研究了非线性拟西Φ-伪压缩映象与Φ-伪压缩映象的不动点的迭代逼近问题.研究结果表明:在任意实的Banac h空间E中,拟Φ-伪压缩映象与Φ-伪压缩映象T(T不必连续)的具误差的Ishikawa与Mann迭代序列强收敛于T的唯一不动点.所得结果不但改进和推广了最近一些文献的相关结果,而且也改进了定理的证明方法.     

Banach空间中非线性$\Phi$-伪压缩映象不动点的迭代逼近

本文研究了非线性拟$\Phi$-伪压缩映象与$\Phi$-伪压缩映象的不动点的迭代逼近问题.研究结果表明: 在任意实的Banach空间$E$中,拟$\Phi$-伪压缩映象与$\Phi$-伪压缩映象$T$~($T$不必连续)的具误差的Ishikawa与Mann迭代序列强收敛于$T$的唯一不动点.所得结果不但改进和推广了最近一些文献的相关结果,而且也改进了定理的证明方法.     

Banach空间中严格渐近伪压缩映象的收敛性问题

在一致凸的Banach空间中，采用新的证明方法研究了严格渐近伪压缩映象和渐近非膨胀映象带误差的修正的Mann和Ishikawa迭代程序的收敛性问题，不要求定义域、值域有界，且迭代系数更简单．     

无限族渐近k-严格伪压缩映象的强收敛定理

在H ilbert空间框架下,给出了迭代逼近无限族渐近k-严格伪压缩映象的公共不动点的杂交投影算法,并证明了一个强收敛定理.此结果改进和推广了原有的相关结果.     

渐近伪压缩型映象不动点的迭代逼近

在赋范空间中引入有限族渐近伪压缩型映象,在较弱条件下,在赋范空间中建立了有限族渐近伪压缩型映象不动点的带误差的迭代算法的一个强收敛定理.也给出几个例子说明结果的有效性与广泛性,从而改进和推广了Rafiq和其他人的结果.     

Three kinds of hybrid algorithms and their numerical realizations for a finite family of quasi-asymptotically pseudocontractive mappings

Numerical Algorithms - The purpose of this article is to propose three new hybrid projection methods for a finite family of quasi-asymptotically pseudocontractive mappings. The strong convergence...     

严格伪压缩映像族隐格式迭代逼近不动点几何结果

对非线性算子迭代序列逼近不动点过程的几何结构进行研究,在提出并证明了一个H ilbert空间中收敛序列的钝角原理基础上,应用这个钝角原理研究了严格伪压缩映像族的隐格式迭代序列逼近公共不动点的几何结构.并证明了相应的钝角原理.这个钝角原理表述了严格伪压缩映像族的隐格式迭代序列逼近公共不动点时与公共不动点集形成了钝角关系.这个钝角关系是使用相应内积序列的上极限表示的.事实上这个钝角结果的表述形式也是一个几何变分不等式,迭代序列的极限点即是这个几何变分不等式的解.一方面这个钝角结果表述了严格伪压缩映像族公共不动点隐格式逼近的几何过程,另一方面,这个钝角结果自然是隐格式迭代序列逼近严格伪压缩映像族公共不动点的必要条件.     

Weak and strong convergence theorems of an implicit iteration for a countable family of continuous pseudocontractive mappings

To approximate a common fixed point of a countable family of continuous pseudocontractive mappings, we introduce an implicit iteration sequence. A necessary and sufficient condition for the convergence of a sequence of such iterates for countably many continuous pseudocontractive mappings is given. We also prove the convergence theorems of an implicit iteration sequence for a countable family of strictly pseudocontractive mappings.     

Some results on generalized equilibrium problems involving strictly pseudocontractive mappings

In this paper,we consider an iterative sequence for generalized equilibrium problems and strictly pseudocontractive mappings.We show that the iterative sequence converges strongly to a common element of the solution set of generalized equilibrium problems and of the fixed point set of strictly pseudocontractive mappings.     

The new composite implicit iterative process with errors for common fixed points of a finite family of strictly pseudocontractive mappings

Convergence theorems for approximation of common fixed points of strictly pseudocontractive mappings of Browder-Petryshyn type are proved in Banach spaces using a new composite implicit iteration scheme with errors. The results presented in this paper generalize and improve the corresponding results of M.O. Osilike [M.O. Osilike, Implicit iteration process for common fixed points of a finite family of strictly pseudocontractive maps, J. Math. Anal. Appl. 294 (2004) 73-81].     

Convergence theorems for implicit iteration process for a finite family of continuous pseudocontractive mappings

In this paper, a necessary and sufficient conditions for the strong convergence to a common fixed point of a finite family of continuous pseudocontractive mappings are proved in an arbitrary real Banach space using an implicit iteration scheme recently introduced by Xu and Ori [H.K. Xu, R.G. Ori, An implicit iteration process for nonexpansive mappings, Numer. Fuct. Anal. Optim. 22 (2001) 767-773] in condition αn∈(0,1], and also strong and weak convergence theorem of a finite family of strictly pseudocontractive mappings of Browder-Petryshyn type is obtained. The results presented extend and improve the corresponding results of M.O. Osilike [M.O. Osilike, Implicit iteration process for common fixed points of a finite family of strictly pseudocontractive maps, J. Math. Anal. Appl. 294 (2004) 73-81].     

迭代序列逼近非线性映像不动点集的一个几何结构

设E是Hilbert空间,T：D(T)→R(T)是E中具非空不动点集F(T)的非线性映像,许多非线性映像的多种形式的迭代序列{X_n}可逼近映像T的不动点p0∈F(T),并且逼近过程{X_n}与不动点集F(T)有密切的几何关系,其中一种几何关系可描述为钝角原理,其准确表述为lim sup_n→+∞〈p—p0,■〉■0,■p∈F(T)．或令θ_n(p)=arccos〈■〉,■p∈F(T)．钝角原理可表述为liminf_n→+∞θ_n(p)■π/2．在相应条件下,具有这种几何关系的非线性映像包括非扩张映像、渐近非扩张映像、Lipschitz映像、增生映像、伪压缩映像、渐近伪压缩映像、严格伪压缩映像、强伪压缩映像等大量非线性映像．钝角原理一方面可揭示非线性映像不动点逼近过程的几何结构,也是迭代逼近非线性映像不动点的必要条件．     

Strong convergence of iterative methods by strictly pseudocontractive mappings in Banach spaces

In this paper we deal with fixed point computational problems by strongly convergent methods involving strictly pseudocontractive mappings in smooth Banach spaces. First, we prove that the S-iteration process recently introduced by Sahu in [14] converges strongly to a unique fixed point of a mapping T, where T is κ-strongly pseudocontractive mapping from a nonempty, closed and convex subset C of a smooth Banach space into itself. It is also shown that the hybrid steepest descent method converges strongly to a unique solution of a variational inequality problem with respect to a finite family of λ_i-strictly pseudocontractive mappings from C into itself. Our results extend and improve some very recent theorems in fixed point theory and variational inequality problems. Particularly, the results presented here extend some theorems of Reich (1980) [1] and Yamada (2001) [15] to a general class of λ-strictly pseudocontractive mappings in uniformly smooth Banach spaces.