• Honam Mathematical Journal
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• v.35 no.2
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• pp.109-117
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• 2013

In the present paper, we utilize the notion of converse commuting mappings due to L$\ddot{u}$ [On common fixed points for converse commuting self-maps on a metric spaces, Acta. Anal. Funct. Appl. 4(3) (2002), 226-228] and prove a common fixed point theorem in Menger space using an implicit relation. We also give an illustrative example to support our main result.

• Honam Mathematical Journal
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• v.34 no.1
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• pp.77-84
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• 2012

In this paper, we define the weakly commuting mapping and prove the fixed point theorem for weakly commuting mappings under some conditions on intuitionistic fuzzy metric spaces.

• The Korean Journal of Community Living Science
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• v.15 no.4
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• pp.137-148
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• 2004

Due to the changes of modern society, alternative types of nuclear family so called as commuting family have appeared. Also, with the increase of women's economic participation and their needs of self-actualization, dual-career commuting family have increased. The purpose of this study was to investigate whether there is any difference between the traditional commuting family and dual-career commuting family in terms of family relation, types of child-care and social support. Also, this study qualitatively analysed parenting-guilty of the mothers of commuting family. One eight seven mothers of three to eight year-old participated the survey. The main results were as follows : (1) In case of traditional commuting family, children cohabit with the mother and usually fathers move between two houses. But among the dual-career commuting family, there are some children who cohabit with the father and some mothers who move. Dual-career commuting family relied on the more types of child-care than traditional commuting family. (2) While traditional commuting family get more support for child-rearing from the husband's family of origin than dual-career commuting family, wife's family of origin provide more support to the dual-career commuting family. The more support the husband's family of origin provide, the more stress both types of commuting family experience. However, there was no significant relationship between the support from the wife's family of origin or friends and the stress of the mothers of both types of commuting family. (3) Mothers of two types of commuting families were different regarding the motives of parenting-guilty Difficulty of caring the children for their job as well as father-absentness makes mothers of dual-career commuting family feel parenting-guilty more.

• Journal of Convergence for Information Technology
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• v.7 no.3
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• pp.65-71
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• 2017

The quantum logic was introduced by G. Birkhoff and 1. von Neumann in order to study projections of a Hilbert space for a formulation of quantum mechanics, and Husimi proposed orthomodular law and orthomodular lattices to complement the quantum logic. Abott introduced orthoimplication algebras and its properties to investigate an implication of orthomodular lattice. The commuting relation is an important property on orthomodular lattice which is related with the distributive law and the modular law, etc. In this paper, we define a binary operation on orthoimplication algebra and the greatest lower bound by using this operation and research some properties of this operation. Also we define a homomorphism and characterize the commuting relation of orthoimplication algebra by the homomorphism.

• Bulletin of the Korean Mathematical Society
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• v.51 no.1
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• pp.207-211
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• 2014

The aim of this paper is to prove the next result. Let n > 1 be an integer and let R be a n!-torsion free semiprime ring. Suppose that f : R ${\rightarrow}$ R is an additive mapping satisfying the relation [f(x), $x^n$] = 0 for all $x{\in}R$. Then f is commuting on R.

• Journal of applied mathematics & informatics
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• v.30 no.1_2
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• pp.265-278
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• 2012

In this work we have considered several common fixed point results in metric spaces for weak compatible mappings. By applications of these results we establish some fixed point theorems in fuzzy metric spaces.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.2 s.36
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• pp.77-88
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• 2006

Overpopulation has been one of the most serious problem of the Seoul Metropolitan Area (SMA), which consists of the City of Seoul, Incheon, and the whole of Gyeonggi Province. People have been still moving into SMA, especially being concentrated into the fringe of Seoul. This study examines the inner city decline phenomenon of SMA which can be easily found in large cities over the world, based on the demographic data of these area. In addition, this study monitors the imbalance in growing of SMA by analyzing RMI (Rank Mobility Index), and the inverse relation between the self sufficiency of the adjacent area and the commuting rate to Seoul by analyzing commuting data. Even though the total population has been unchanged, the internal change of population was substantial. The growth of Seoul Metro region was placed near the city of Seoul, especially commuter data reassured the population concentrations. The results will be useful in urban planning and growth management.

• Journal of the Korean Home Economics Association
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• v.29 no.3
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• pp.113-130
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• 1991

The objectives of study were 1) to investigate the motives for moving to the current residence, 2) to analyze residential satisfaction after moving in relation to household characteristics and the motives for moving, and 3) to test relationships among household characteristics, residential satisfaction before moving, motives for moving, and residential satisfaction after moving. Residential satisfaction was evaluated in relation to housing, neighborhood, and socio-psychological environments. Methdo-logy included literature and questionnaire survey. Questionnaires were administered to 269 homemakers living in an apartment complex in seoul. Data were analyzed with the use of SPSSS PC+ computer package. The motives for moving were classified in five types: tenureship improvement, improvement of the physical condition of housing, improvement of neighborhood environment, commuting improvement, and constraints. There were significant differences in the types of motives for moving by socio-economic status, types of houses lived in previously, change in type of tenures, and the duration of residence before moving. There were significant differences in residential satisfaction after moving among types of houses lived in previously, change in type of tenures, and the types of the motives for moving. There were significant relationships among residential satisfaction variables. They were the socio-economic status, change in type of tenures, residential satisfaction before moving.

• Journal of Korean Society of Transportation
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• v.31 no.3
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• pp.74-85
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• 2013

We analyze the efficiency of congestion pricings and transit subsidies in the spatial micro-economic model based on a general equilibrium environment. In this setting, we decompose the total welfare change into component factors and identify the reason of the change in the efficiency caused by policy instruments; these component factors are divided into indirect factors and direct factors including of origin-destination and mode choices. We set up the model as adding mode choice to the standard format in the fashion of Anas and Kim (1996) and extend the methodology proposed by Yu and Rhee (2011) and Rhee (2012) for deriving theoretical and analytical solution. Most of welfare gain comes from the modal shift from car to bus. The relative efficiency of subsidies in relation to the first-best pricing is lower than it of congestion pricings although the change in bus share by subsidies is similar to it by congestion pricing. Subsidies give rise to more modal shift from a car to a bus for long-distance commuting than it caused by congestion pricings. As the increase of bus share for long-distance commuting leads to the increase of cross-commuters passing through CBD, the welfare gain by subsidies is lower than it by congestion pricings.

• Journal of the Korean Geographical Society
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• v.42 no.3 s.120
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• pp.421-433
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• 2007

The Metropolitan Areas have experienced the phenomenon that some of their peripheral parts emerged as a core business area because of the relocation of residential and economic activities from the central area. An important phenomenon in the spatial transformation of metropolitan area is the weakening of centrality in the center and the increasing strength of centrality in the periphery. This paper examined the changing patterns of spatial interaction in the Seoul Metropolitan area through an analysis on outflow trips. Outflow trip by Seoul decreased in nearby regions and increased in remote regions, however as times goes by, the spatial patterns of the largest outflow trip destination were diversified and the rate of outflow trip to Seoul has decreased in the periphery regions. This research reveals that the most remarkable changes of spatial interactions occurred nearby regions of Seoul and also the changes of outflow trip by Seoul was also distinct. In relation to this, the results arising from the similarity analysis by the variance of trip clearly show the changing spatial patterns of interaction in Yongin, Seoul, Suwon and Hwaseong.