• 제목/요약/키워드: Nonexpansive mapping

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Fixed Point Theorems for Multivalued Mappings in Banach Spaces

  • Bae, Jong Sook;Park, Myoung Sook
    • 충청수학회지
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    • 제3권1호
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    • pp.103-110
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    • 1990
  • Let K be a nonempty weakly compact convex subset of a Banach space X and T : K ${\rightarrow}$ C(X) a nonexpansive mapping satisfying $P_T(x){\cap}clI_K(x){\neq}{\emptyset}$. We first show that if I - T is semiconvex type then T has a fixed point. Also we obtain the same result without the condition that I - T is semiconvex type in a Banach space satisfying Opial's condition. Lastly we extend the result of [5] to the case, that T is an 1-set contraction mapping.

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An Iterative Method for Equilibrium and Constrained Convex Minimization Problems

  • Yazdi, Maryam;Shabani, Mohammad Mehdi;Sababe, Saeed Hashemi
    • Kyungpook Mathematical Journal
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    • 제62권1호
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    • pp.89-106
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    • 2022
  • We are concerned with finding a common solution to an equilibrium problem associated with a bifunction, and a constrained convex minimization problem. We propose an iterative fixed point algorithm and prove that the algorithm generates a sequence strongly convergent to a common solution. The common solution is identified as the unique solution of a certain variational inequality.

REMARKS ON APPROXIMATION OF FIXED POINTS OF STRICTLY PSEUDOCONTRACTIVE MAPPINGS

  • Kim, Tae-Hwa;Kim, Eun-Suk
    • 대한수학회보
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    • 제37권3호
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    • pp.461-475
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    • 2000
  • In the present paper, we first give some examples of self-mappings which are asymptoticaly nonexpansive in the intermediate, not strictly hemicontractive, but satisfy the property (H). It is then shown that the modified Mann and Ishikawa iteration processes defined by $x_{n+1}=(1-\alpha_n)x_n+\alpha_nT^nx_n\ and\ x_{n+1}=(1-\alpha_n)x_n+\alpha_nT^n[(1-\beta_n)x_n+\beta_nT^nx_n]$,respectively, converges strongly to the unique fixed point of such a self-mapping in general Banach spaces.

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COMMON FIXED POINTS UNDER LIPSCHITZ TYPE CONDITION

  • Pant, Vyomesh
    • 대한수학회보
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    • 제45권3호
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    • pp.467-475
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    • 2008
  • The aim of the present paper is three fold. Firstly, we obtain common fixed point theorems for a pair of selfmaps satisfying nonexpansive or Lipschitz type condition by using the notion of pointwise R-weak commutativity but without assuming the completeness of the space or continuity of the mappings involved (Theorem 1, Theorem 2 and Theorem 3). Secondly, we generalize the results obtained in first three theorems for four mappings by replacing the condition of noncompatibility of maps with the property (E.A) and using the R-weak commutativity of type $(A_g)$ (Theorem 4). Thirdly, in Theorem 5, we show that if the aspect of noncompatibility is taken in place of the property (E.A), the maps become discontinuous at their common fixed point. We, thus, provide one more answer to the problem posed by Rhoades [11] regarding the existence of contractive definition which is strong enough to generate fixed point but does not forces the maps to become continuous.

STRONG CONVERGENCE OF THE MODIFIED HYBRID STEEPEST-DESCENT METHODS FOR GENERAL VARIATIONAL INEQUALITIES

  • Yao, Yonghong;Noor, Muhammad Aslam
    • Journal of applied mathematics & informatics
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    • 제24권1_2호
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    • pp.179-190
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    • 2007
  • In this paper, we consider the general variational inequality GVI(F, g, C), where F and g are mappings from a Hilbert space into itself and C is the fixed point set of a nonexpansive mapping. We suggest and analyze a new modified hybrid steepest-descent method of type method $u_{n+l}=(1-{\alpha}+{\theta}_{n+1})Tu_n+{\alpha}u_n-{\theta}_{n+1g}(Tu_n)-{\lambda}_{n+1}{\mu}F(Tu_n),\;n{\geq}0$. for solving the general variational inequalities. The sequence $\{x_n}\$ is shown to converge in norm to the solutions of the general variational inequality GVI(F, g, C) under some mild conditions. Application to constrained generalized pseudo-inverse is included. Results proved in the paper can be viewed as an refinement and improvement of previously known results.

STRONG CONVERGENCE OF EXTENDED GENERAL VARIATIONAL INEQUALITIES AND NONEXPANSIVE MAPPINGS

  • Chen, Jun-Min;Zhang, Li-Juan;He, Zhen
    • East Asian mathematical journal
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    • 제26권1호
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    • pp.59-67
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    • 2010
  • In this paper, we suggest and analyze some three step iterative scheme for finding the common elements of the set of the solutions of the extended general variational inequalities involving three operators and the set of the fixed points of nonexpansive mappings. We also consider the convergence analysis of suggested iterative schemes under some mild conditions. Since the extended general variational inequalities include general variational inequalities and several other classes of variational inequalities as special cases, results obtained in this paper continue to hold for these problems. Results obtained in this paper may be viewed as a refinement and improvement of the previously known results.

A NEW MAPPING FOR FINDING A COMMON SOLUTION OF SPLIT GENERALIZED EQUILIBRIUM PROBLEM, VARIATIONAL INEQUALITY PROBLEM AND FIXED POINT PROBLEM

  • Farid, Mohammad;Kazmi, Kaleem Raza
    • Korean Journal of Mathematics
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    • 제27권2호
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    • pp.297-327
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    • 2019
  • In this paper, we introduce and study a general iterative algorithm to approximate a common solution of split generalized equilibrium problem, variational inequality problem and fixed point problem for a finite family of nonexpansive mappings in real Hilbert spaces. Further, we prove a strong convergence theorem for the sequences generated by the proposed iterative scheme. Finally, we derive some consequences from our main result. The results presented in this paper extended and unify many of the previously known results in this area.

OUTER APPROXIMATION METHOD FOR ZEROS OF SUM OF MONOTONE OPERATORS AND FIXED POINT PROBLEMS IN BANACH SPACES

  • Abass, Hammad Anuoluwapo;Mebawondu, Akindele Adebayo;Narain, Ojen Kumar;Kim, Jong Kyu
    • Nonlinear Functional Analysis and Applications
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    • 제26권3호
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    • pp.451-474
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    • 2021
  • In this paper, we investigate a hybrid algorithm for finding zeros of the sum of maximal monotone operators and Lipschitz continuous monotone operators which is also a common fixed point problem for finite family of relatively quasi-nonexpansive mappings and split feasibility problem in uniformly convex real Banach spaces which are also uniformly smooth. The iterative algorithm employed in this paper is design in such a way that it does not require prior knowledge of operator norm. We prove a strong convergence result for approximating the solutions of the aforementioned problems and give applications of our main result to minimization problem and convexly constrained linear inverse problem.