• Journal of the Korean Mathematical Society
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• v.35 no.2
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• pp.361-370
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• 1998

A condition for a certain maximal operator to be of weak type (p, p) is studied. This operator unifies various maximal operators cited in the literatures.

• Kyungpook Mathematical Journal
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• v.43 no.4
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• pp.593-604
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• 2003

In this paper we introduce the integral type Lupas-$B{\acute{e}}zier$ operator $\tilde{B}_{n,{\alpha}}$, which is a new approximation operator of probabilistic type. We study the rate of pointwise convergence of the operators $\tilde{B}_{n,{\alpha}}$ for local bounded functions and get an asymptotically estimate by means of some methods and techniques of probability theory.

• Journal of the Korean Mathematical Society
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• v.38 no.2
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• pp.337-348
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• 2001

The unitary Lie-Trotter-Kato product formula gives in a simplest way a meaning to the Feynman path integral for the Schroding-er equation. In this note we want to survey some of recent results on the norm convergence of the selfadjoint Lie-Trotter Kato product formula for the Schrodinger operator -1/2Δ + V(x) and for the sum of two selfadjoint operators A and B. As one of the applications, a remark is mentioned about an approximation therewith to the fundamental solution for the imaginary-time Schrodinger equation.

• Bulletin of the Korean Mathematical Society
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• v.57 no.2
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• pp.383-391
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• 2020

We study the mapping property of multilinear fractional maximal operators in Lipschitz spaces. It should be pointed out that some of the techniques employed in the study of fractional integral operators do not apply to fractional maximal operators.

• Honam Mathematical Journal
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• v.29 no.1
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• pp.9-18
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• 2007

In this paper we establish the existence theorem of the operator-valued function space integral $K_{\lambda}(F)$ for $\lambda\in\mathbb{C}_{+,\lambda_0}^\sim$ where F is of the form (1.1). Our result is a generalization for Johnson and Skoug result in [8].

• Honam Mathematical Journal
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• v.26 no.4
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• pp.455-462
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• 2004

We prove that if ${\mathbb{K}}^*$ is adjoint operator on $W_2{^2}({\Omega})$, then ${\mathbb{K}}^*v(t,\;{\tau})=,\;v(x,\;y){\in}W_2{^2}({\Omega})$ ; it is also related to the decomposition of solution of Fredholm equations.

• Journal of the Korean Mathematical Society
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• v.36 no.5
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• pp.855-890
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• 1999

Necessary and sufficient conditions on the weight functions u(.) and $\upsilon$(.) are derived in order that the fractional maximal operator $M\alpha,\;0\;\leq\;\alpha\;<\;1$, is bounded from the weighted amalgam space $\ell^s(L^p(\mathbb{R},\upsilon(x)dx)$ into $\ell^r(L^q(\mathbb{R},u(x)dx)$ whenever $1\leq s\leq r<\infty\;and\;1. The boundedness problem for the fractional intergral operator $I_{\alpha},0<\alpha\leq1$, is also studied.

• Journal of applied mathematics & informatics
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• v.41 no.5
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• pp.1103-1114
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• 2023

The aim of the present paper is to obtain some mapping properties of subordinations by certain univalent functions in the open unit disk associated with a family of linear operators. Moreover, we also consider some applications for integral operators.

• Journal of the Korean Mathematical Society
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• v.33 no.4
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• pp.929-954
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• 1996

• East Asian mathematical journal
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• v.15 no.1
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• pp.91-103
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• 1999