• Title/Summary/Keyword: function algebra

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ULTRASEPARABILITY OF CERTAIN FUNCTION ALGEBRAS

  • Hwang, Sun-Wook
    • Communications of the Korean Mathematical Society
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    • v.9 no.2
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    • pp.299-302
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    • 1994
  • Throughout this paper, let X be a compact Hausdorff space, and let C(X) (resp. $C_{R}$ /(X)) be the complex (resp. real) Banach algebra of all continuous complex-valued (resp. real-valued) functions on X with the pointwise operations and the supremum norm x. A Banach function algebra on X is a Banach algebra lying in C(X) which separates the points of X and contains the constants. A Banach function algebra on X equipped with the supremum norm is called a uniform algebra on X, that is, a uniformly closed subalgebra of C(X) which separates the points of X and contains the constants.(omitted)

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ON UNIFORMLY ULTRASEPARATING FAMILY OF FUNCTION ALGEBRAS

  • Hwang, Sunwook
    • Bulletin of the Korean Mathematical Society
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    • v.30 no.1
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    • pp.125-134
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    • 1993
  • Let X be a compact Hausdorff space, and let C(X) (resp. $C_{R}$(X)) be the complex (resp. real) Banach algebra of all continuous complex-valued(resp. real-valued) functions on X with the pointwise operations and the supremum norm x. A Banach function algebra on X is a Banach algebra lying in C(X) which separates the points of X and contains the constants. A Banach function algebra on X equipped with the supremum norm is called a uniform algebra on X, that is, a uniformly closed subalgebra of C(X) which separates the points of X and contains the constants.s.

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PROJECTIVE LIMIT OF A SEQUENCE OF BANACH FUNCTION ALGEBRAS AS A FRECHET FUNCTION ALGEBRA

  • Sady. F.
    • Bulletin of the Korean Mathematical Society
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    • v.39 no.2
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    • pp.259-267
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    • 2002
  • Let X be a hemicompact space with ($K_{n}$) as an admissible exhaustion, and for each n $\in$ N, $A_{n}$ a Banach function algebra on $K_{n}$ with respect to $\parallel.\parallel_n$ such that $A_{n+1}\midK_{n}$$\subsetA_n$ and${\parallel}f{\mid}K_n{\parallel}_n{\leq}{\parallel}f{\parallel}_{n+1}$ for all f$\in$$A_{n+1}$, We consider the subalgebra A = { f $\in$ C(X) : $\forall_n\;{\epsilon}\;\mathbb{N}$ of C(X) as a frechet function algebra and give a result related to its spectrum when each $A_{n}$ is natural. We also show that if X is moreover noncompact, then any closed subalgebra of A cannot be topologized as a regular Frechet Q-algebra. As an application, the Lipschitzalgebra of infinitely differentiable functions is considered.d.

A VERTEX PROPERTY OF REAL FUNCTION ALGEBRAS

  • Hwang, Sun-Wook
    • The Pure and Applied Mathematics
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    • v.5 no.1
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    • pp.65-72
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    • 1998
  • We investigate a chain of properties of real function algebras along the analogous proofs of the complex cases such as the fact that any real function algebra which is both maximal and essential is pervasive. And some properties of real function algebras with a vertex property will be discussed.

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ON THE FAILURE OF GORENSTEINESS FOR THE SEQUENCE (1, 125, 95, 77, 70, 77, 95, 125, 1)

  • Ahn, Jeaman
    • Journal of the Chungcheong Mathematical Society
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    • v.28 no.4
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    • pp.537-543
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    • 2015
  • In [9], the authors determine an infinite class of non-unimodal Gorenstein sequence, which includes the example $$\bar{h}_1\text{ = (1, 125, 95, 77, 71, 77, 95, 125, 1)}$$. They raise a question whether there is a Gorenstein algebra with Hilbert function $$\bar{h}_2\text{= (1, 125, 95, 77, 70, 77, 95, 125, 1)}$$, which has remained an open question. In this paper, we prove that there is no Gorenstein algebra with Hilbert function $\bar{h}_2$.

MIRROR d-ALGEBRAS

  • So, Keum Sook;Kim, Young Hee
    • Journal of applied mathematics & informatics
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    • v.31 no.3_4
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    • pp.559-564
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    • 2013
  • In this paper we investigate necessary conditions for the mirror algebra $(M(X),{\bigoplus},(0,0))$ to be a $d$-algebra (having the condition (D5), resp.) when (X, *, 0) is a d-algebra (having the condition (D5), resp.). Moreover, we obtain the necessary conditions for M(X) of a $d^*$-algebra X to be a $d^*$-algebra.

IDEMPOTENT ELEMENTS IN THE LOTKA-VOLTERRA ALGEBRA

  • Yoon, Suk-Im
    • Communications of the Korean Mathematical Society
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    • v.10 no.1
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    • pp.123-131
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    • 1995
  • The notion of our non-associative algebra is obtained from the Lotka-Volterra system of differential equation describing competitiion between animals or vegetals species and also in the kinetic theory of gasses. For the structure of an algebra, the existence of idempotents is of particular interest. But also from the biological aspect the existence of such elements is of interest because the equilibria of a population which can be described by an algebra correspond to idempotents of this algebra. Thus we present some properties of the general natures for a Lotka-Volterra algebra associated to a weight function and idempotents elements.

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HARMONIC OPERATORS IN $L^p(V N(G))$

  • Lee, Hun Hee
    • Journal of the Chungcheong Mathematical Society
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    • v.25 no.2
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    • pp.319-329
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    • 2012
  • For a norm 1 function ${\sigma}$ in the Fourier-Stieltjes algebra of a locally compact group we define the space of ${\sigma}$-harmonic operators in the non-commutative $L^p$-space associated to the group von Neumann algebra of G. We will investigate some properties of the space and will obtain a precise description of it.

Certain Models of the Lie Algebra 𝒦5 and Their Connection with Special Functions

  • Yadav, Sarasvati;Rani, Geeta
    • Kyungpook Mathematical Journal
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    • v.58 no.4
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    • pp.615-625
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    • 2018
  • In this paper, we discuss the connection between the 5-dimensional complex Lie algebra ${\mathcal{K}} _5$ and Special functions. We construct certain two variable models of the irreducible representations of ${\mathcal{K}}_5$. We also use an Euler type integral transformation to obtain the new transformed models, in which the basis function appears as $_2F_1$. Further, we utilize these models to get some generating functions and recurrence relations.

APPROXIMATE IDENTITY OF CONVOLUTION BANACH ALGEBRAS

  • Han, Hyuk
    • Journal of the Chungcheong Mathematical Society
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    • v.33 no.4
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    • pp.497-504
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    • 2020
  • A weight ω on the positive half real line [0, ∞) is a positive continuous function such that ω(s + t) ≤ ω(s)ω(t), for all s, t ∈ [0, ∞), and ω(0) = 1. The weighted convolution Banach algebra L1(ω) is the algebra of all equivalence classes of Lebesgue measurable functions f such that ‖f‖ = ∫0∞|f(t)|ω(t)dt < ∞, under pointwise addition, scalar multiplication of functions, and the convolution product (f ⁎ g)(t) = ∫0t f(t - s)g(s)ds. We give a sufficient condition on a weight function ω(t) in order that L1(ω) has a bounded approximate identity.