• 제목/요약/키워드: almost closed

검색결과 200건 처리시간 0.027초

S-closed 공간(空間)과 RC 수렴(收斂)에 관하여 (A Note on S-closed Space and RC-convergence.)

  • 한천호
    • 산업기술연구
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    • 제5권
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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.

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ON δgs-CLOSED SETS AND ALMOST WEAKLY HAUSDORFF SPACES

  • Park, Jin-Han;Song, Dae-Seob;Lee, Bu-Young
    • 호남수학학술지
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    • 제29권4호
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    • pp.597-615
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    • 2007
  • The aim of this paper is to introduce the class of ${\delta}gs$-closed sets and obtain characterizations of almost weakly Hausdorff spaces due to Dontchev and Ganster. We also introduce the notion of ${\delta}gs$-continuity and investigate the relationships between it and other types of continuity.

ALMOST INVERTIBILITY MODULO CLOSED IDEALS

  • Kim, Yong-Tae;Lee, Woo-Young;Lee, Hae-Jin
    • 대한수학회보
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    • 제28권2호
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    • pp.185-190
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    • 1991
  • The concept of "almost invertibility modulo closed ideals" in L(X, Y) was introduced, implicitly, by Robin Harte [1, Theorem 3.9.5]. The aims of this note are to make the formal definition of "almost left and right invertible modulo closed ideals" operators and show that they form open sets.they form open sets.

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SOME EXAMPLES OF ALMOST GCD-DOMAINS

  • Chang, Gyu Whan
    • 충청수학회지
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    • 제24권3호
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    • pp.601-607
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    • 2011
  • Let D be an integral domain, X be an indeterminate over D, and D[X] be the polynomial ring over D. We show that D is an almost weakly factorial PvMD if and only if D + XDS[X] is an integrally closed almost GCD-domain for each (saturated) multiplicative subset S of D, if and only if $D+XD_1[X]$ is an integrally closed almost GCD-domain for any t-linked overring $D_1$ of D, if and only if $D_1+XD_2[X]$ is an integrally closed almost GCD-domain for all t-linked overrings $D_1{\subseteq}D_2$ of D.

A NOTE ON SCALAR CURVATURE FUNCTIONS OF ALMOST-KÄHLER METRICS

  • Kim, Jongsu
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제20권3호
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    • pp.199-206
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    • 2013
  • We present a 4-dimensional nil-manifold as the first example of a closed non-K$\ddot{a}$hlerian symplectic manifold with the following property: a function is the scalar curvature of some almost K$\ddot{a}$hler metric iff it is negative somewhere. This is motivated by the Kazdan-Warner's work on classifying smooth closed manifolds according to the possible scalar curvature functions.

NEW CARDINAL FUNCTIONS RELATED TO ALMOST CLOSED SETS

  • Cho, Myung Hyun;Moon, Mi Ae;Kim, Junhui
    • 호남수학학술지
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    • 제35권3호
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    • pp.541-550
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    • 2013
  • In this paper, we strengthen the properties of approximation by points (AP) and weak approximation by points (WAP) considered by A. Pultr and A. Tozzi in 1993 to define ${\kappa}$-AP and ${\kappa}$-WAP for an infinite cardinal ${\kappa}$. We also strengthen the properties of radial and pseudoradial to define ${\kappa}$-radial and ${\kappa}$-pseudoradial for an infinite cardinal ${\kappa}$. These allow us to consider new cardinal functions related to almost closed sets; AP-number, WAP-number, radial number, and pseudoradial number. We study their properties and show the relationships between them. We also provide some examples around ${\kappa}$-AP and ${\kappa}$-WAP which are closely connected with ${\kappa}$-radial and ${\kappa}$-pseudoradial.

ON FUZZY BITOPOLOGICAL SPACES IN ŠOSTAK'S SENSE (II)

  • Ramadan, Ahmed Abd El-Kader;Abbas, Salah El-Deen;El-Latif, Ahmed Aref Abd
    • 대한수학회논문집
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    • 제25권3호
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    • pp.457-475
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    • 2010
  • In this paper, we have use a fuzzy bitopological space (X, $\tau_1$, $\tau_2$) to create a family $\tau_{ij}^s$ which is a supra fuzzy topology on X. Also, we introduce and study the concepts of r-($\tau_i$, $\tau_j$)-generalized fuzzy regular closed, r-($\tau_i$, $\tau_j$)-generalized fuzzy strongly semi-closed and r-($\tau_i$, $\tau_j$)-generalized fuzzy regular strongly semi-closed sets in fuzzy bitopological space in the sense of $\check{S}$ostak. Also, these classes of fuzzy subsets are applied for constructing several type of fuzzy closed mapping and some type of fuzzy separation axioms called fuzzy binormal, fuzzy mildly binormal and fuzzy almost pairwise normal.