Strong and weak convergence theorems for asymptotically nonexpansive mappings

被引:150
作者
Chidume, CE [1 ]
Ofoedu, EU
Zegeye, H
机构
[1] Abdus Salam Int Ctr Theoret Phys, Trieste, Italy
[2] Nnamdi Azikiwe Univ, Dept Math, Awka, Anambra, Nigeria
关键词
asymptotically nonexpansive nonself-maps; demiclosed; modulus of convexity;
D O I
10.1016/S0022-247X(03)00061-1
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
Suppose K is a nonempty closed convex nonexpansive retract of a real uniformly convex Banach space E with P as a nonexpansive retraction. Let T: K --> E be an asymptotically nonexpansive nonself-map with sequence {k(n}ngreater than or equal to1) subset of [1, infinity), lim k(n) = 1, F(T) := {x is an element of K: Tx = x} not equal emptyset. Suppose {x(n)}(ngreater than or equal to1) is generated iteratively by x(1) is an element of K, x(n+1) = P((1 - alpha(n))x(n) + alpha(n)T(PT)(n-1) x(n)), n greater than or equal to 1, where {alpha(n)}(ngreater than or equal to1) subset of (0, 1) is such that epsilon < 1 - alpha(n) < 1 - epsilon for some epsilon > 0. It is proved that (1 - T) is demiclosed at 0. Moreover, if Sigma(ngreater than or equal to1)(k(n)(2) - 1) < infinity and T is completely continuous, strong convergence Of {x(n)} I to some x* is an element of F(T) is proved. If T is not assumed to be completely continuous but E also has a Frechet differentiable norm, then weak convergence Of {x(n)} I to some x* is an element of F(T) is obtained. (C) 2003 Elsevier Science (USA). All rights reserved.
引用
收藏
页码:364 / 374
页数:11
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