• Title/Summary/Keyword: Nonexpansive mappings

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CONVERGENCE THEOREMS FOR TWO FAMILIES OF WEAK RELATIVELY NONEXPANSIVE MAPPINGS AND A FAMILY OF EQUILIBRIUM PROBLEMS

  • Zhang, Xin;Su, Yongfu
    • Communications of the Korean Mathematical Society
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    • v.25 no.4
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    • pp.583-607
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    • 2010
  • The purpose of this paper is to prove strong convergence theorems for common fixed points of two families of weak relatively nonexpansive mappings and a family of equilibrium problems by a new monotone hybrid method in Banach spaces. Because the hybrid method presented in this paper is monotone, so that the method of the proof is different from the original one. We shall give an example which is weak relatively nonexpansive mapping but not relatively nonexpansive mapping in Banach space $l^2$. Our results improve and extend the corresponding results announced in [W. Takahashi and K. Zembayashi, Strong convergence theorem by a new hybrid method for equilibrium problems and relatively nonexpansive mappings, Fixed Point Theory Appl. (2008), Article ID 528476, 11 pages; doi:10.1155/2008/528476] and [Y. Su, Z. Wang, and H. Xu, Strong convergence theorems for a common fixed point of two hemi-relatively nonexpansive mappings, Nonlinear Anal. 71 (2009), no. 11, 5616?5628] and some other papers.

APPROXIMATING COMMON FIXED POINTS OF A SEQUENCE OF ASYMPTOTICALLY QUASI-f-g-NONEXPANSIVE MAPPINGS IN CONVEX NORMED VECTOR SPACES

  • Lee, Byung-Soo
    • The Pure and Applied Mathematics
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    • v.20 no.1
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    • pp.51-57
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    • 2013
  • In this paper, we introduce asymptotically quasi-$f-g$-nonexpansive mappings in convex normed vector spaces and consider approximating common fixed points of a sequence of asymptotically quasi-$f-g$-nonexpansive mappings in convex normed vector spaces.

BROWDER'S TYPE STRONG CONVERGENCE THEOREM FOR S-NONEXPANSIVE MAPPINGS

  • Kim, Jong-Kyu;Sahu, Daya Ram;Anwar, Sajid
    • Bulletin of the Korean Mathematical Society
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    • v.47 no.3
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    • pp.503-511
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    • 2010
  • We prove a common fixed point theorem for S-contraction mappings without continuity. Using this result we obtain an approximating curve for S-nonexpansive mappings in a Banach space and prove Browder's type strong convergence theorem for this approximating curve. The demiclosedness principle for S-nonexpansive mappings is also established.

WEAK CONVERGENCE THEOREMS FOR EQUILIBRIUM PROBLEMS AND NONEXPANSIVE MAPPINGS AND NONSPREADING MAPPINGS IN HILBERT SPACES

  • Jiang, Li;Su, Yongfu
    • Communications of the Korean Mathematical Society
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    • v.27 no.3
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    • pp.505-512
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    • 2012
  • In this paper, we introduce an iterative scheme for finding a common element of the set of fixed points of a nonexpansive mappings and nonspreading mappings and the set of solution of an equilibrium problem on the setting of real Hilbert spaces.

Strong Convergence Theorems for Asymptotically Nonexpansive Mappings by Hybrid Methods

  • Qin, Xiaolong;Su, Yongfu;Shang, Meijuan
    • Kyungpook Mathematical Journal
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    • v.48 no.1
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    • pp.133-142
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    • 2008
  • In this paper, we prove two strong convergence theorems for asymptotically nonexpansive mappings in Hibert spaces by hybrid methods. Our results extend and improve the recent ones announced by Nakajo, Takahashi [K. Nakajo, W. Takahashi, Strong convergence theorems for nonexpansive mappings and nonexpansive semigroups, J. Math. Anal. Appl. 279 (2003) 372-379], Kim, Xu [T. H. Kim, H. K. Xu, Strong convergence of modified mann iterations for asymptotically nonexpansive mappings and semigroups, Nonlinear Anal. 64 (2006) 1140-1152], Martinez-Yanes, Xu [C. Martinez-Yanes, H. K. Xu, Strong convergence of the CQ method for fixed point iteration processes, Nonlinear Anal. 64 (2006) 2400-2411] and some others.

AN ITERATIVE ALGORITHM FOR ASYMPTOTICALLY NONEXPANSIVE MAPPINGS

  • Yao, Yonghong;Liou, Yeong-Cheng;Kang, Shin-Min
    • Journal of applied mathematics & informatics
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    • v.28 no.1_2
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    • pp.75-86
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    • 2010
  • An iterative algorithm was been studied which can be viewed as an extension of the previously known algorithms for asymptotically nonexpansive mappings. Subsequently, we study the convergence problem of the proposed iterative algorithm for asymptotically nonexpansive mappings under some mild conditions in Banach spaces.

APPROXIMATIONS OF THE ITERATIVE SEQUENCES FOR ASYMPTOTICALLY NONEXPANSIVE MAPPINGS IN BANACH SPACES

  • Chang, Shih-Sen;Cho, Yeol-Je;Zhou, Haiyun
    • East Asian mathematical journal
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    • v.24 no.1
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    • pp.125-137
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    • 2008
  • In this paper, we first introduce some iterative sequences of Halpern type for asymptotically nonexpansive mappings and nonexpansive mappings in Banach spaces and then we discuss strong convergence for the iterative processes. The results presented in this paper extend, supplement and improve the correspoding main results of Reich [11], Shimizu and Takahashi [13], Shioji and Takahashi [15], [16] and Wittmann [18].

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COMMON FIXED POINT OF GENERALIZED ASYMPTOTIC POINTWISE (QUASI-) NONEXPANSIVE MAPPINGS IN HYPERBOLIC SPACES

  • Saleh, Khairul;Fukhar-ud-din, Hafiz
    • Korean Journal of Mathematics
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    • v.28 no.4
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    • pp.915-929
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    • 2020
  • We prove a fixed point theorem for generalized asymptotic pointwise nonexpansive mapping in the setting of a hyperbolic space. A one-step iterative scheme approximating common fixed point of two generalized asymptotic pointwise (quasi-) nonexpansive mappings in this setting is provided. We obtain ∆-convergence and strong convergence theorems of the iterative scheme for two generalized asymptotic pointwise nonexpansive mappings in the same setting. Our results generalize and extend some related results in the literature.

Remarks on Fixed Point Theorems of Non-Lipschitzian Self-mappings

  • Kim, Tae-Hwa;Jeon, Byung-Ik
    • Kyungpook Mathematical Journal
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    • v.45 no.3
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    • pp.433-443
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    • 2005
  • In 1994, Lim-Xu asked whether the Maluta's constant D(X) < 1 implies the fixed point property for asymptotically nonexpansive mappings and gave a partial solution for this question under an additional assumption for T, i.e., weakly asymptotic regularity of T. In this paper, we shall prove that the result due to Lim-Xu is also satisfied for more general non-Lipschitzian mappings in reflexive Banach spaces with weak uniform normal structure. Some applications of this result are also added.

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COMMON FIXED POINTS OF TWO NONEXPANSIVE MAPPINGS BY A MODIFIED FASTER ITERATION SCHEME

  • Khan, Safeer Hussain;Kim, Jong-Kyu
    • Bulletin of the Korean Mathematical Society
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    • v.47 no.5
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    • pp.973-985
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    • 2010
  • We introduce an iteration scheme for approximating common fixed points of two mappings. On one hand, it extends a scheme due to Agarwal et al. [2] to the case of two mappings while on the other hand, it is faster than both the Ishikawa type scheme and the one studied by Yao and Chen [18] for the purpose in some sense. Using this scheme, we prove some weak and strong convergence results for approximating common fixed points of two nonexpansive self mappings. We also outline the proofs of these results to the case of nonexpansive nonself mappings.