• 제목/요약/키워드: fixed-point iteration

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On the Equivalance of Some Fixed Point Iterations

  • Ozdemir, Murat;Akbulut, Sezgin
    • Kyungpook Mathematical Journal
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    • 제46권2호
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    • pp.211-217
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    • 2006
  • In this paper, we have shown that the convergence of one-step, two-step and three-step iterations is equivalent, which are known as Mann, Ishikawa and Noor iteration procedures, for a special class of Lipschitzian operators defined in a closed, convex subset of an arbitrary Banach space.

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A CYCLIC AND SIMULTANEOUS ITERATIVE ALGORITHM FOR THE MULTIPLE SPLIT COMMON FIXED POINT PROBLEM OF DEMICONTRACTIVE MAPPINGS

  • Tang, Yu-Chao;Peng, Ji-Gen;Liu, Li-Wei
    • 대한수학회보
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    • 제51권5호
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    • pp.1527-1538
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    • 2014
  • The purpose of this paper is to address the multiple split common fixed point problem. We present two different methods to approximate a solution of the problem. One is cyclic iteration method; the other is simultaneous iteration method. Under appropriate assumptions on the operators and iterative parameters, we prove both the proposed algorithms converge to the solution of the multiple split common fixed point problem. Our results generalize and improve some known results in the literatures.

Convergence analysis of fixed-point iteration with Anderson Acceleration on a simplified neutronics/thermal-hydraulics system

  • Lee, Jaejin;Joo, Han Gyu
    • Nuclear Engineering and Technology
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    • 제54권2호
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    • pp.532-545
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    • 2022
  • In-depth convergence analyses for neutronics/thermal-hydraulics (T/H) coupled calculations are performed to investigate the performance of nonlinear methods based on the Fixed-Point Iteration (FPI). A simplified neutronics-T/H coupled system consisting of a single fuel pin is derived to provide a testbed. The xenon equilibrium model is considered to investigate its impact during the nonlinear iteration. A problem set is organized to have a thousand different fuel temperature coefficients (FTC) and moderator temperature coefficients (MTC). The problem set is solved by the Jacobi and Gauss-Seidel (G-S) type FPI. The relaxation scheme and the Anderson acceleration are applied to improve the convergence rate of FPI. The performances of solution schemes are evaluated by comparing the number of iterations and the error reduction behavior. From those numerical investigations, it is demonstrated that the number of FPIs is increased as the feedback is stronger regardless of its sign. In addition, the Jacobi type FPIs generally shows a slower convergence rate than the G-S type FPI. It also turns out that the xenon equilibrium model can cause numerical instability for certain conditions. Lastly, it is figured out that the Anderson acceleration can effectively improve the convergence behaviors of FPI, compared to the conventional relaxation scheme.

AN IMPLICIT ITERATES FOR NON-LIPSCHITZIAN ASYMPTOTICALLY QUASI-NONEXPANSIVE TYPE MAPPINGS IN CAT(0) SPACES

  • Saluja, G.S.
    • East Asian mathematical journal
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    • 제28권1호
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    • pp.81-92
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    • 2012
  • The purpose of this paper is to establish strong convergence of an implicit iteration process to a common fixed point for a finite family of asymptotically quasi-nonexpansive type mappings in CAT(0) spaces. Our results improve and extend the corresponding results of Fukhar-ud-din et al. [15] and some others from the current literature.

Fixed point iterations for quasi-contractive maps in uniformly smooth banach spaces

  • Chidume, C.E.;Osilike, M.O.
    • 대한수학회보
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    • 제30권2호
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    • pp.201-212
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    • 1993
  • It is our purpose in this paper to first establish an inequality in real uniformly smooth Banach spaces with modulus of smoothness of power type q > 1 that generalizes a well known Hilbert space inequality. Using our inequality, we shall then extend the above result of Qihou [15] on the Ishikawa iteration process from Hilbert spaces to these much more general Banach spaces. Furthermore, we shall prove that the Mann iteration process converges strongly to the unique fixed point of a quasi-contractive map in this general setting. No compactness assumption on K is required in our theorems.

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The Three-step Intermixed Iteration for Two Finite Families of Nonlinear Mappings in a Hilbert Space

  • Suwannaut, Sarawut;Kangtunyakarn, Atid
    • Kyungpook Mathematical Journal
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    • 제62권1호
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    • pp.69-88
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    • 2022
  • In this work, the three-step intermixed iteration for two finite families of nonlinear mappings is introduced. We prove a strong convergence theorem for approximating a common fixed point of a strict pseudo-contraction and strictly pseudononspreading mapping in a Hilbert space. Some additional results are obtained. Finally, a numerical example in a space of real numbers is also given and illustrated.

On the iteration of holomorphic mappings in $ $

  • Kwon, Oh-Nam
    • 대한수학회논문집
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    • 제11권3호
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    • pp.681-694
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    • 1996
  • Let F be a germ of analytic transformation from $(C^2, O)$ to $C^2, O)$. Let a, b denote the eigenvalues of DF(O). O is called a semi-attrative fixed point if $$\mid$a$\mid$ = 1, 0 < $\mid$b$\mid$ < 1 = 1, 0 < $\mid$a$\mid$ < 1)$. O is called a super-attractive fixed point if a = 0, b = 0. We discuss such a mapping from the point of view of dynamical systems.

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INERTIAL PICARD NORMAL S-ITERATION PROCESS

  • Dashputre, Samir;Padmavati, Padmavati;Sakure, Kavita
    • Nonlinear Functional Analysis and Applications
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    • 제26권5호
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    • pp.995-1009
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    • 2021
  • Many iterative algorithms like that Picard, Mann, Ishikawa and S-iteration are very useful to elucidate the fixed point problems of a nonlinear operators in various topological spaces. The recent trend for elucidate the fixed point via inertial iterative algorithm, in which next iterative depends on more than one previous terms. The purpose of the paper is to establish convergence theorems of new inertial Picard normal S-iteration algorithm for nonexpansive mapping in Hilbert spaces. The comparison of convergence of InerNSP and InerPNSP is done with InerSP (introduced by Phon-on et al. [25]) and MSP (introduced by Suparatulatorn et al. [27]) via numerical example.