• Bulletin of the Korean Mathematical Society
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• v.30 no.1
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• pp.99-107
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• 1993

A vector space K with scalar product <.,.> is called a Krein space if it can be decomposed as a northogonal sum of a Hilbert space and an anti-space of a Hilbert space. The space K induces a Hilbert space $K_{J}$ in the inner product <.,.> $K_{J}$=<.,.>K, where $J^{2}$=I. the eigenspaces of J are denoted by $K^{+}$$_{J}$, which is a Hilbert space and $K^{-}$$_{J}$, which is an anti-space of a Hilbert space. Then the Krein space K is the orthogonal sum of $K^{+}$$_{J}$ and $K^{-}$$_{J}$. Such a decomposition of K is called a fundamental decomposition. In general, fundamental decompositions are not unique. The norm of the Hilbert space depends on the choice of a fundamental decomposion, but such norms are equivalent. The topology generated by these norms is called the strong or Mackey topology of K. It is used to define all topological notions on the Krein space K with respect to this topology. The Pontryagin index of a Krein space is the dimension of the antispace of a Hilbert space in any such decomposition. the dimension does not depend on the choice of orthogonal decomposition. A Krein space is called a Pontryagin space if it has finite Pontryagin index.dex.yagin index.dex.

• Journal of the Korean Home Economics Association
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• v.39 no.5
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• pp.123-135
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• 2001

The purpose of this paper is to examine bedroom-need norms and the relationship between normative deficits for bedroom sharing and housing space satisfaction of adolescent. Three cases were mainly considered to apply for adolescents to share a bedroom: maximum age and number limits of a child sharing a parents'bedroom, maximum age of an old child sharing a bedroom with its siblings of the opposite sex, and maximum age of an old child sharing a bedroom with its siblings of the same sex. The data were collected 400 eighth grade students in the three different size of regions, June-July, 1999 and 379 cases were finally analyzed. The result showed that the normative deficits for bedroom sharing was a statistically signiticant factor to explain housing space satisfaction of adolescents even though the condition of bedroom sharing was the most influencial variable. This reset supports the family housing adjustment behavior model of Morris and Winter.

• East Asian mathematical journal
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• v.24 no.3
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• pp.223-232
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• 2008

The purpose of this paper is to prove common fixed point theorem for multivalued mappings satisfying some conditions in intuitionistic fuzzy metric space in the sense of Alaca et al.

• Honam Mathematical Journal
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• v.41 no.3
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• pp.619-629
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• 2019

On the setting of the pluriharmonic Dirichlet space, we describe the essential norm of an operator which is a finite sum of products of several Toeplitz operators.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2005.05a
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• pp.253-254
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• 2005

Space Composition should be understood an aesthetic cognition about the basis of space in different points of view. It establishes the prescribed environment of space through the hypothesis of given geometrical object. Therefore, it makes understand the cause of space composition and conceive the consistency of various elements, orders, norms and forms of space composition, Through this study, the students may build up scenarios-form the beginning to the climax of space -, directions and full stories about the space.

• Journal of Aerospace System Engineering
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• v.16 no.2
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• pp.33-38
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• 2022

In recent years, the space sector has been changing rapidly. The militarization of outer space is openly underway. On the other hand, space commercialization by private capital called "Newspace" is emerging in the U.S. Additionally, the Artemis project, a manned space moon exploration project, is being resumed 50 years after the end of the Apollo program. Eventually, the commercial use of space resources is actively being discussed. Due to the rapidly developing space technologies, the U.N. Space Treaty, enacted in 1967, has established the norms and principles of space activities. However, it may be nearing the end of its life. To confront the challenges of a new space era, Korea must engage in various legal and policy studies to meet these changes.

• Journal of the Korean Mathematical Society
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• v.50 no.1
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• pp.137-159
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• 2013

It is studied the linear combinations of composition operators on the Banach space of bounded harmonic functions on the open unit disk. We determine the essential norm of them.

• Journal of the Korean Mathematical Society
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• v.42 no.5
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• pp.975-1002
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• 2005

On the setting of the upper half-space H of the Eu­clidean n-space, we show the boundedness of weighted Bergman projection for 1 < p < $\infty$ and nonorthogonal projections for 1 $\leq$ p < $\infty$ . Using these results, we show that Bergman norm is equiva­ lent to the normal derivative norms on weighted harmonic Bergman spaces. Finally, we find the dual of b$\_{$^{1}$.

• Bulletin of the Korean Mathematical Society
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• v.44 no.2
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• pp.309-313
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• 2007

By applying ideas from [M. S. Moslehian, et al., Norms of operators in $X_{\lambda}$ spaces, Appl. Math. Lett. (2007), doi:10.1016/j.aml.2006. 11.009], we investigate the norm of the cubic operator on the function space $X_{\lambda}$.

• East Asian mathematical journal
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• v.21 no.1
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• pp.41-48
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• 2005

In this paper we first introduce a space of homogeneous type X, and then consider a kind of generalized upper half-space $X{\times}(0,\;\infty)$. We are mainly considered with inequalities for the $L^p$ norms of area functions associated with approach regions in $X{\times}(0,\;\infty)$.