• 제목/요약/키워드: Convex mapping

검색결과 134건 처리시간 0.024초

A PROOF OF A CONVEX-VALUED SELECTION THEOREM WITH THE CODOMAIN OF A FRECHET SPACE

  • Cho, Myung-Hyun;Kim, Jun-Hui
    • 대한수학회논문집
    • /
    • 제16권2호
    • /
    • pp.277-285
    • /
    • 2001
  • The purpose of this paper is to give a proof of a generalized convex-valued selection theorem which is given by weakening a Banach space to a completely metrizable locally convex topological vector space, i.e., a Frechet space. We also develop the properties of upper semi-continuous singlevalued mapping to those of upper semi-continuous multivalued mappings. These properties wil be applied in our further consideraations of selection theorems.

  • PDF

CONVERGENCE THEOREMS FOR ASYMPTOTICALLY NONEXPANSIVE MAPPINGS IN BANACH SPACES

  • Wu, Changqun;Xu, Sumei
    • Journal of applied mathematics & informatics
    • /
    • 제27권3_4호
    • /
    • pp.661-672
    • /
    • 2009
  • In this paper, we introduce a modified three-step iteration scheme with errors for asymptotically nonexpansive mappings in the framework of uniformly convex Banach spaces. Weak and strong convergence theorems are established.

  • PDF

A THREE-TERM INERTIAL DERIVATIVE-FREE PROJECTION METHOD FOR CONVEX CONSTRAINED MONOTONE EQUATIONS

  • Noinakorn, Supansa;Ibrahim, Abdukarim Hassan;Abubakar, Auwal Bala;Pakkaranang, Nuttapol
    • Nonlinear Functional Analysis and Applications
    • /
    • 제26권4호
    • /
    • pp.839-853
    • /
    • 2021
  • Let 𝕽n be an Euclidean space and g : 𝕽n → 𝕽n be a monotone and continuous mapping. Suppose the convex constrained nonlinear monotone equation problem x ∈ 𝕮 s.t g(x) = 0 has a solution. In this paper, we construct an inertial-type algorithm based on the three-term derivative-free projection method (TTMDY) for convex constrained monotone nonlinear equations. Under some standard assumptions, we establish its global convergence to a solution of the convex constrained nonlinear monotone equation. Furthermore, the proposed algorithm converges much faster than the existing non-inertial algorithm (TTMDY) for convex constrained monotone equations.

REMARKS ON THE KKM STRUCTURES OF KHANH AND QUAN

  • Sehie Park
    • Nonlinear Functional Analysis and Applications
    • /
    • 제28권1호
    • /
    • pp.123-134
    • /
    • 2023
  • Since Knaster, Kuratowski, and Mazurkiewicz established their KKM theorem in 1929, it was first applied to topological vector spaces mainly by Fan and Granas. Later it was extended to convex spaces by Lassonde and to extensions of c-spaces by Horvath. In 1992, such study was called the KKM theory by ourselves. Then the theory was extended to generalized convex spaces or G-convex spaces. Motivated by such spaces, there have appeared several particular types of artificial spaces. In 2006 we introduced abstract convex spaces which contain all existing spaces appeared in the KKM theory. Later in 2014-2020, Khahn and Quan introduced "topologically based existence theorems" and the so-called KKM structure. In the present paper, we show that their structure is a particular type of already known KKM spaces.

SPH에서의 Convex Hull 알고리즘 적용연구 (A Syudy on Applications of Convex Hull Algorithm in the SPH)

  • 이진성;이영신
    • 한국군사과학기술학회지
    • /
    • 제14권2호
    • /
    • pp.313-320
    • /
    • 2011
  • SPH(Smoothed Particle Hydrodynamics) is a gridless Lagrangian technique that is useful as an alternative numerical analysis method used to analyze high deformation problems as well as astrophysical and cosmological problems. In SPH, all points within the support of the kernel are taken as neighbours. The accuracy of the SHP is highly influenced by the method for choosing neighbours from all particle points considered. Typically a linked-list method or tree search method has been used as an effective tool because of its conceptual simplicity, but these methods have some liability in anisotropy situations. In this study, convex hull algorithm is presented as an improved method to eliminate this artifact. A convex hull is the smallest convex set that contains a certain set of points or a polygon. The selected candidate neighbours set are mapped into the new space by an inverse square mapping, and extract a convex hull. The neighbours are selected from the shell of the convex hull. These algorithms are proved by Fortran programs. The programs are expected to use as a searching algorithm in the future SPH program.

NEW HYBRID ALGORITHM FOR WEAK RELATIVELY NONEXPANSIVE MAPPING AND INVERSE-STRONGLY MONOTONE MAPPING IN BANACH SPACE

  • Zhang, Xin;Su, Yongfu;Kang, Jinlong
    • Journal of applied mathematics & informatics
    • /
    • 제29권1_2호
    • /
    • pp.87-102
    • /
    • 2011
  • The purpose of this paper is to prove strong convergence theorems for finding a common element of the set of fixed points of a weak relatively nonexpansive mapping and the set of solutions of the variational inequality for an inverse-strongly-monotone mapping by a new hybrid method in a Banach space. 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 by Ying Liu[Ying Liu, Strong convergence theorem for relatively nonexpansive mapping and inverse-strongly-monotone mapping in a Banach space, Appl. Math. Mech. -Engl. Ed. 30(7)(2009), 925-932] and some others.

CONVERGENCE OF APPROXIMATING PATHS TO SOLUTIONS OF VARIATIONAL INEQUALITIES INVOLVING NON-LIPSCHITZIAN MAPPINGS

  • Jung, Jong-Soo;Sahu, Daya Ram
    • 대한수학회지
    • /
    • 제45권2호
    • /
    • pp.377-392
    • /
    • 2008
  • Let X be a real reflexive Banach space with a uniformly $G\hat{a}teaux$ differentiable norm, C a nonempty closed convex subset of X, T : C $\rightarrow$ X a continuous pseudocontractive mapping, and A : C $\rightarrow$ C a continuous strongly pseudocontractive mapping. We show the existence of a path ${x_t}$ satisfying $x_t=tAx_t+(1- t)Tx_t$, t $\in$ (0,1) and prove that ${x_t}$ converges strongly to a fixed point of T, which solves the variational inequality involving the mapping A. As an application, we give strong convergence of the path ${x_t}$ defined by $x_t=tAx_t+(1-t)(2I-T)x_t$ to a fixed point of firmly pseudocontractive mapping T.

Some Inclusion Properties of New Subclass of Starlike and Convex Functions associated with Hohlov Operator

  • Sokol, Janusz;Murugusundaramoorthy, Gangadharan;Kothandabani, Thilagavathi
    • Kyungpook Mathematical Journal
    • /
    • 제56권2호
    • /
    • pp.597-610
    • /
    • 2016
  • For a sufficiently adequate special case of the Dziok-Srivastava linear operator defined by means of the Hadamard product (or convolution) with Srivastava-Wright convolution operator, the authors investigate several mapping properties involving various subclasses of analytic and univalent functions, $G({\lambda},{\alpha})$ and $M({\lambda},{\alpha})$. Furthermore we discuss some inclusion relations for these subclasses to be in the classes of k-uniformly convex and k-starlike functions.