• Communications of the Korean Mathematical Society
• /
• v.30 no.3
• /
• pp.277-282
• /
• 2015

We obtain some conditions for disconnectedness of a topological space in terms of maximal and minimal open sets, and some similar results in terms of maximal and minimal closed sets along with interrelations between them. In particular, we show that if a space has a set which is both maximal and minimal open, then either this set is the only nontrivial open set in the space or the space is disconnected. We also obtain a result concerning a minimal open set on a subspace.

• Honam Mathematical Journal
• /
• v.29 no.1
• /
• pp.41-54
• /
• 2007

In this paper, we introduce the notion of $g{\cdot}{\gamma}$-closed sets and study its basic properties. Also we introduce the notion of ${\gamma}-T_*$ spaces and investigate relationships among these spaces and ${\gamma}-T_i$ spaces (i = 0,1/2,1) due to Ogata [5].

• 제어로봇시스템학회:학술대회논문집
• /
• 1994.10a
• /
• pp.289-292
• /
• 1994

In this paper, the equations of motion are constructed systematically for multibody systems containing closed kinematic loops. For the displacement analysis of the closed loops, we introduce a new mixed coordinates by adding to the reference coordinates, relative coordinates corresponding to the degrees of freedom of the system. The mixed coordinates makes easy derive the explicit closed form solution. The explicit functional relationship expressed in closed form is of great advantages in system dimension reduction and no need of an iterative scheme for the displacement analysis. This forms of equation are built up in the general purpose computer program for the kinematic and dynamic analysis of multiboty systems.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.6 no.3
• /
• pp.255-263
• /
• 2006

In this paper, we introduce the concepts of ${\gamma}$-fuzzy feebly open and ${\gamma}$-fuzzy feebly closed sets in Sostak's fuzzy topological spaces and by using them, we explain the notions of ${\gamma}$-fuzzy F-closed spaces. Also, we give some characterization of ${\gamma}$-fuzzy F-closedness in terms of fuzzy filterbasis and ${\gamma}$-fuzzy feebly-${\theta}$-cluster points.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2002.11a
• /
• pp.109-112
• /
• 2002

So far, the closed-form Green's functions have been derived almost for th open microstrip structures. In the present study, closed-form Green's functions for a top-covered microstrip structure are derived. And an effect of top-cover is discussed in comparison with open structure.

• Journal of applied mathematics & informatics
• /
• v.38 no.5_6
• /
• pp.463-468
• /
• 2020

The purpose of this article is to study the concepts of fuzzy mean open and fuzzy mean closed sets in fuzzy topological spaces. Further, in what way they are similar to those of other. Also we discuss some properties of fuzzy mean open and fuzzy mean closed with fuzzy paraopen and fuzzy paraclosed sets in fuzzy topology.

• Korean Journal of Mathematics
• /
• v.25 no.3
• /
• pp.437-453
• /
• 2017

A new class of sets, called generalized (${\Lambda}$, b)-closed sets, has been introduced and studied. Also, several properties of generalized (${\Lambda}$, b)-closed sets are investigated. Some characterizations of ${\Lambda}_b$-regular spaces and ${\Lambda}_b$-normal spaces are discussed.

• Communications of the Korean Mathematical Society
• /
• v.25 no.4
• /
• pp.623-628
• /
• 2010

Nakaoka and Oda ([1] and [2]) introduced the notion of maximal open sets and minimal closed sets in topological spaces. In this paper, we introduce new classes of sets called maximal $\theta$-open sets, minimal $\theta$-closed sets, $\theta$-semi maximal open and $\theta$-semi minimal closed and investigate some of their fundamental properties.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2002.05a
• /
• pp.62-65
• /
• 2002

A dieless forming system which consists of hydraulic punch elements and elastomer/fluid pads, was developed for sheet metal forming. 2-D curved surface forming was carried out using open-loop, closed-loop, and repeated forming method. Closed-loop exhibited higher decision than open-loop forming. Repeated forming also showed reduced spring back and possibility of high precision.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.11 no.3
• /
• pp.280-285
• /
• 2001

We introduce the new concepts of some fuzzy continuous and closed mappings and study their properties. Also we investigate the properties of fuzzy mildly normal spaces.