• Honam Mathematical Journal
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• v.37 no.3
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• pp.287-297
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• 2015

In this paper, we investigate $T_1$ Boolean subalgebras of the Boolean algebra consisting all regular closed sets in a space and their Wallman covers. In particular, we will give sufficient and necessary conditions of spaces X satisfying ${\beta}E_{cc}(X)=E_{cc}({\beta}X)$.

• Bulletin of the Korean Mathematical Society
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• v.50 no.2
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• pp.667-674
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• 2013

Considering a special double-cover Q of the symmetric group of degree 3, we show that a proper non-regular approximate symmetry occurs from its quasigroup homogeneous space. The weak compatibility of any two elements of Q is completely characterized in any such quasigroup homogeneous space of degree 4.

• Bulletin of the Korean Mathematical Society
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• v.31 no.2
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• pp.187-192
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• 1994

The author extended the small properties of topological semilattices to that of regular semigroups [3]. In this paper, it could be shown that a semigroup S is almost regular if and only if over bar RL = over bar R.cap.L for every right ideal R and every left ideal L of S. Moreover, it has shown that the Bohr compactification of an almost regular semigroup is regular. Throughout, a semigroup will mean a topological semigroup which is a Hausdorff space together with a continuous associative multiplication. For a semigroup S, we denote E(S) by the set of all idempotents of S. An element x of a semigroup S is called regular if and only if x .mem. xSx. A semigroup S is termed regular if every element of S is regular. If x .mem. S is regular, then there exists an element y .mem S such that x xyx and y = yxy (y is called an inverse of x) If y is an inverse of x, then xy and yx are both idempotents but are not always equal. A semigroup S is termed recurrent( or almost pointwise periodic) at x .mem. S if and only if for any open set U about x, there is an integer p > 1 such that x$^{p}$ .mem.U.S is said to be recurrent (or almost periodic) if and only if S is recurrent at every x .mem. S. It is known that if x .mem. S is recurrent and .GAMMA.(x)=over bar {x,x$^{2}$,..,} is compact, then .GAMMA.(x) is a subgroup of S and hence x is a regular element of S.

• Journal of the Korean Institute of Educational Facilities
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• v.11 no.1
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• pp.25-37
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• 2004

This study is derived from a problem for the blind, how to recognize the space and how to find their way. Unlike ordinary people, the disabled people are closely related with special constructor environment using the other sense. Especially, to find his/her location, each person depends on the wayfinding ability as acquiring specific and various information,(e.g. recognizing figure by tactile sense, space size by auditory sense, direction by light from a window and regular noise, and existence of switch in a specific place.) Those senses help the person's wayfinding to his/her destination. The procedure of wayfinding are location, position, orientation, navigation, and movement. Consequently, construction for the people above mentioned can offer a design-guideline considering following factors, building arrangement considering regular noise, refurbishment, plan configuration of floor and wall-skin changed, circulation stream that maintains right angle by the regular noise in the building, enforcement location character by the inflow of the light into a crossing.

• Communications of the Korean Mathematical Society
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• v.20 no.3
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• pp.521-529
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• 2005

We prove that the dimension of the space of positive (bounded, respectively) solutions for the Schrodinger operator whose potential q is nonnegative on a graph with q-regular ends is equal to the number of ends (q-nonparabolic ends, respectively).

• Bulletin of the Korean Mathematical Society
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• v.37 no.3
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• pp.601-618
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• 2000

Let (and $g^*$) be the space of regular test (and generalized, resp.) white noise functions. The integral kernel operators acting on and transformation groups of operators on are studied, and then every integral kernel operator acting on can be extended to continuous linear operator on $g^*$. The existence and uniqueness of solutions of Cauchy problems associated with certain integral kernel operators with intial data in $g^*$ are investigated.

• Journal of Industrial Technology
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• v.5
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• pp.47-49
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• 1985

Semi-open을 기초로 하여 만들어진 S-closed 공간의 일반적인 성질을 살펴보고 S-closed 공간과 (maximum) filterbase와의 관계를 조사하였다. 이를 바탕으로 regular closed된 cover C, regular open set인 족(族) C, rc-accumulation, (maximum) filterbase에서의 관계(關係)를 살펴 보았다. Mapping theory에서 almost-open almost-continuous map f가 almost continuous되는 것을 보였다.

• Journal of applied mathematics & informatics
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• v.16 no.1_2
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• pp.621-632
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• 2004

Multiresoluton analysis(MRA) of space of square integrable functions defined on whole entire line has been well-known. But for many applications, MRA on bounded interval was required and studied. In this paper we give a MRA for $L^2$(0, 1) by means of periodic wavelets based on regular MRA for $L^2$(R) and give the convergence of partial sums.

• Journal of the Chungcheong Mathematical Society
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• v.34 no.1
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• pp.85-92
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• 2021

In present paper, inspired by the recently paper [1], we give the mixed pressure-velocity regular criteria in view of Lorentz spaces for weak solutions to 3D micropolar equations in a half space. Precisely, if (0.1) ${\frac{P}{(e^{-{\mid}x{\mid}^2}+{\mid}u{\mid})^{\theta}}{\in}L^p(0,T;L^{q,{\infty}}({\mathbb{R}}^3_+))$, p, q < ∞, and (0.2) ${\frac{2}{p}}+{\frac{3}{q}}=2-{\theta}$, 0 ≤ θ ≤ 1, then (u, w) is regular on (0, T].

• Kyungpook Mathematical Journal
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• v.60 no.1
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• pp.117-125
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• 2020

In this paper, we first introduce new classes of Lipschitz algebras of infinitely differentiable functions which are extensions of the standard Lipschitz algebras of infinitely differentiable functions. Then we determine the maximal ideal space of these extended algebras. Finally, we show that if X and K are uniformly regular subsets in the complex plane, then R(X, K) is natural.