• Kyungpook Mathematical Journal
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• v.46 no.4
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• pp.463-476
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• 2006

It is known that there are no real hypersurfaces with parallel Ricci tensor in a nonflat complex space form ([6], [9]). In this paper we investigate real hypersurfaces in a complex projective space $P_n\mathbb{C}$ using some conditions of the Ricci tensor S which are weaker than ${\nabla}S=0$. We characterize Hopf hypersurfaces of $P_n\mathbb{C}$.

• Bulletin of the Korean Mathematical Society
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• v.36 no.2
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• pp.315-336
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• 1999

In the paper [12] we have introduced the new kind of pseudo-einstein ruled real hypersurfaces in complex space forms $M_n(c), c\neq0$, which are foliated by pseudo-Einstein leaves. The purpose of this paper is to give a geometric condition for non-proper pseudo-Einstein ruled real hypersurfaces to be totally geodesic in the sense of Kimura [8] for c> and Ahn, Lee and the present author [1] for c<0.

• Bulletin of the Korean Mathematical Society
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• v.59 no.4
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• pp.897-904
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• 2022

In this paper, we obtain an inequality involving the squared norm of the covariant differentiation of the shape operator for a real hypersurface in nonflat complex space forms. It is proved that the equality holds for non-Hopf case if and only if the hypersurface is ruled and the equality holds for Hopf case if and only if the hypersurface is of type (A).

• Communications of the Korean Mathematical Society
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• v.38 no.1
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• pp.179-193
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• 2023

In this article, we derived Chen's inequality for warped product bi-slant submanifolds in generalized complex space forms using semisymmetric metric connections and discuss the equality case of the inequality. Further, we discuss non-existence of such minimal immersion. We also provide various applications of the obtained inequalities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5673-5682
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• 2015

Purpose of this study is to examine and investigate the utilization of low-rise floor Pilotis space which is frequently selected as a major planning element in recent high-rise apartment complex and to identify the interrelationship between the placement of Pilotis space in the complex and space utilization frequency by comparing circulation related indicators of Connectivity, Control Value, Global Integration and Local Integration through Space Syntax axial analysis. Conclusions of this study are, first, Pilotis space is not used as a space to improve regional community consciousness because it is mostly used as a 'simple movement space'. Second, regarding space utilization frequency differences in Pilotis space in each apartment building, projecting entry access+pilotis addition type complex shows more significant utilization frequency than pilotis access type complex, and the vandalism phenomenon is observed more often. Third, Pilotis space utilization is related with Connectivity, Control Value, Global Integration and Local Integration which are circulation related indicators in Space Syntax, and Pilotis spaces with high indicator values over 2 tend to show higher utilization frequency and those with low indicator values over 2 tend to show low utilization frequency.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.2
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• pp.130-139
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• 1999

The survey site, the Hyundai Apartment Complex in the Bundang Model Complex, includes three housing layout types; super high-rise, high-rise and low-rise apartment buildings. The site includes artificial ground over underground parking lots. The overall objective of this study is to evaluate social and physical factors of housing environments in each types of layout. The data has been complied from residents of apartment through questionnaire. The questionnaire include elements of neighborhood, outdoor space, parking zones, and the overall complex design in each layout types. The predictors of outdoor space satisfaction in apartment housing complex are found as follows: "abundance of trees in quantity", "the role as front yards", "harmony of buildings with landscape", "the more distance between buildings" and "maintenance quality of site". Layout of super high-rise apartment site is most satisfied. Introduction of car-free deck space is favored by resident because of safty and quiet resting area. However the low quality of green and lack of shades on the artificial land are identified as problems.on the artificial land are identified as problems.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2004.11a
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• pp.55-60
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• 2004

Regarding the change of life-style, dining and kitchen space has been considered to be more important than before in many ways. At this point of time, it is very significant to understand the trend of the recently planned dining and kitchen space. Thus the purpose of this study is to analyze the dining and kitchen space in the unit of the complex buildings. It is believed that the accumulated data will be the basic information to develop more efficient and convenient dining and kitchen space in future.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.346-351
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• 2006

Community facilities in apartment complex was developed through combination with residents' needs about housing environmental amenity, marketing competition among construction companies and social trend 'Well-being' . But community facilities and fitness center which are situated in the beginning are alienated by residents because the designers plan community facilities without considering about residents' life-style and preference. In this paper, the study includes present status of fitness center and residents' preference for proper fitness center design. The result presents that fitness center users in apartment complex want a resting space which is already located in fitness center of mixed-use residential building. A resting space provides conditions that users can make up with the community each other as well as they can rest after exercise. And the fitness center users prefer wood as interior finish material of floor and wall in exercising space and resting space because they have a feeling comfortable and splendid.

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.3
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• pp.37-44
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• 2009

There is a rapid increase of child care centers due to the growth of women's social activities and a nuclear family. Child care center is an important part of community facilities for apartment housing complex. This study aims to collect the basic data required to develop the planning standards for the child care centers. This research limited the child care centers which is situated to permanent rental housing complex. Therefore, this research presents the basic design guidelines for the space composition planning of child care centers by grasping the special quality connected with the space composition of child care centers among the community facilities that is located in the permanent rental apartment housing complex.

• Kyungpook Mathematical Journal
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• v.58 no.1
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• pp.149-165
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• 2018

A. Bejancu [2] was the first who instigated the new concept in differential geometry, i.e., CR-submanifolds. On the other hand, CR-submanifolds were generalized by B. Y. Chen [7] as slant submanifolds. Further, he gave the notion of a Kaehlerian slant submanifold as a proper slant submanifold. This article has two objectives. For the first objective, we derive Simons' type formula for a minimal Kaehlerian slant submanifold in a complex space form. Then, by applying this formula, we give a complete classification of a minimal Kaehlerian slant submanifold in a complex space form and also obtain its some immediate consequences. The second objective is to prove some results about semi-parallel submanifolds.