• Title/Summary/Keyword: normed linear space.

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LINEAR MAPPINGS, QUADRATIC MAPPINGS AND CUBIC MAPPINGS IN NORMED SPACES

  • Park, Chun-Gil;Wee, Hee-Jung
    • The Pure and Applied Mathematics
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    • v.10 no.3
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    • pp.185-192
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    • 2003
  • It is shown that every almost linear mapping $h{\;}:{\;}X{\;}{\rightarrow}{\;}Y$ of a complex normed space X to a complex normed space Y is a linen. mapping when h(rx) = rh(x) (r > 0,$r\;{\neq}\;1$$x{\;}{\in}{\;}X$, that every almost quadratic mapping $h{\;}:{\;}X{\;}{\rightarrow}{\;}Y$ of a complex normed space X to a complex normed space Y is a quadratic mapping when $h(rx){\;}={\;}r^2h(x){\;}(r{\;}>{\;}0,r\;{\neq}\;1)$ holds for all $x{\;}{\in}{\;}X$, and that every almost cubic mapping $h{\;}:{\;}X{\;}{\rightarrow}{\;}Y$ of a complex normed space X to a complex normed space Y is a cubic mapping when $h(rx){\;}={\;}r^3h(x){\;}(r{\;}>{\;}0,r\;{\neq}\;1)$ holds for all $x{\;}{\in}{\;}X$.

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Best simulaneous approximations in a normed linear space

  • Park, Sung-Ho
    • Bulletin of the Korean Mathematical Society
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    • v.33 no.3
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    • pp.367-376
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    • 1996
  • We characterize best simultaneous approximations from a finite-dimensional subspace of a normed linear space. In the characterization we reveal usefulness of a minimax theorem presented in [2,4].

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REFLEXIVITY OF NORMED ALMOST LINEAR SPACES

  • Lee, Sang-Han
    • Communications of the Korean Mathematical Society
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    • v.10 no.4
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    • pp.855-866
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    • 1995
  • We prove that if a nals X is reflexive, then $X = W_X + V_X$. We prove also that if an als X has a finite basis, then $X = W_X + V_X$ if and only if X is reflexive.

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SOME PROPERTIES OF THE SPACE OF FUZZY BOUNDED LINEAR OPERATORS

  • Hwang, In Ah;Rhie, Gil Seob
    • Journal of the Chungcheong Mathematical Society
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    • v.21 no.3
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    • pp.347-354
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    • 2008
  • In this paper, we will show that ($CF(X,K),{\chi}_{{\parallel}{\mid}{\cdot}{\parallel}{\mid}}$) is a fuzzy Banach space using that the dual space $X^*$ of a normed linear space X is a crisp Banach space. And for a normed linear space Y instead of a scalar field K, we obtain ($CF(X,Y),{\rho}^*$) is a fuzzy Banach space under the some conditions.

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SOME PROPERTIES OF QUOTIENT FUZZY NORMED LINEAR SPACES

  • Hwang, In Ah;Rhie, Gil Seob;Sung, Yeoul Ouk
    • Journal of the Chungcheong Mathematical Society
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    • v.10 no.1
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    • pp.9-15
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    • 1997
  • The main goal of this paper is to investigate some properties of a quotient fuzzy seminorm ${\rho}_q$ induced by a fuzzy seminorm ${\rho}={\chi}_{B_{{\parallel}{\cdot}{\parallel}}}$ on a normed linear space X.

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THE RIESZ THEOREM IN FUZZY n-NORMED LINEAR SPACES

  • Kavikumar, J.;Jun, Young-Bae;Khamis, Azme
    • Journal of applied mathematics & informatics
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    • v.27 no.3_4
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    • pp.541-555
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    • 2009
  • The primary purpose of this paper is to prove the fuzzy version of Riesz theorem in n-normed linear space as a generalization of linear n-normed space. Also we study some properties of fuzzy n-norm and introduce a concept of fuzzy anti n-norm.

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A WEAK COMMON FIXED POINT THEOREM IN NORMED ALMOST LINEAR SPACES

  • Lee, Sang-Han
    • Journal of applied mathematics & informatics
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    • v.4 no.2
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    • pp.573-581
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    • 1997
  • In this paper we prove a weak common fixed point theo-rem in a normed almost linear space which is different from the result of S. P. Singh and B.A. Meade [9]. However for a Banach X our theorem is equal to the result of S. P. Singh and B. A. Meade.

BARRELLEDNESS OF SOME SPACES OF VECTOR MEASURES AND BOUNDED LINEAR OPERATORS

  • FERRANDO, JUAN CARLOS
    • Bulletin of the Korean Mathematical Society
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    • v.52 no.5
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    • pp.1579-1586
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    • 2015
  • In this paper we investigate the barrellednes of some spaces of X-valued measures, X being a barrelled normed space, and provide examples of non barrelled spaces of bounded linear operators from a Banach space X into a barrelled normed space Y, equipped with the uniform convergence topology.