• Bulletin of the Korean Mathematical Society
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• v.59 no.5
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• pp.1237-1246
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• 2022

In this paper, we introduce the concept of N-pure ideal as a generalization of pure ideal. Using this concept, a new and interesting type of rings is presented, we call it a mid ring. Also, we provide new characterizations for von Neumann regular and zero-dimensional rings. Moreover, some results about mp-ring are given. Finally, a characterization for mid rings is provided. Then it is shown that the class of mid rings is strictly between the class of reduced mp-rings (p.f. rings) and the class of mp-rings.

• Communications of the Korean Mathematical Society
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• v.23 no.4
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• pp.487-497
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• 2008

Buchsbaum and Eisenbud showed that every Gorenstein ideal of grade 3 is generated by the submaximal order pfaffians of an alternating matrix. In this paper, we describe a method for constructing a class of type 3, grade 3, perfect ideals which are not Gorenstein. We also prove that they are algebraically linked to an even type grade 3 almost complete intersection.

• Korean Institute of Interior Design Journal
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• no.3
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• pp.85-90
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• 1994

The purpose of this study was to present design direction of a unit plan in elderly housing. In order to perform the above purpose, this study was organized into two sections. First, literature review to understand the relationship between late adulthood development and housing environment, unit plan of elderly housing and design needs. Second, questionnaire and field survey research to seek a design direction of unit plan. Statistics were frequency, percentage, mean and crosstabulated analysis. The major findings were summerized as follows ; 1) The size of ideal single room was 20.4$m^2$-28.5$m^2$, and the minimum size for the couple was 28.5$m^2$. 2) The entrance of each room must not be faced each other, in case of the corridor type building like YooDang village. 3) Spare heater which can be turned on anytime was requested in bathroom especially for wintertime or whenever elderly need more heat. 4) The minimum size of closet was 1.5m per single room and the ideal size of it is over 1.8m. 5) The platform ondol type bed was ideal type bed was ideal for Korean elderly.

• Journal of Families and Better Life
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• v.33 no.1
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• pp.87-97
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• 2015

This study aims to examine how home child care allowance influences a mother's choice of child care type. To accomplish this goal, we surveyed 432 mothers who had at least one child under 5 years old. The data were analyzed by frequencies, percentages, means and binomial logistic regressions. The results showed that unemployed mothers and mothers with younger children had a high tendency to choose home child care allowance instead of child care subsidy. Second, mother's employment status, age of first child and an interactive term of mother's employment status and home child care receipt influenced a concordance between an ideal and actual child care type. Unemployed mothers and mothers with younger children were more likely to experience a concordance between their ideal and actual types of child care. By investigating how home child care allowance affects the right of choice in child care type, this study provides empirical information to policy makers and researchers and contributes to develop cash-benefit policies for families with young children.

• Journal of applied mathematics & informatics
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• v.41 no.2
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• pp.413-437
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• 2023

In this paper, we introduce the concepts of (inf, sup)-hesitant fuzzy subsemigroups and (inf, sup)-hesitant fuzzy (generalized) bi-ideals of semigroups, and investigate their properties. The concepts are established in terms of sets, fuzzy sets, negative fuzzy sets, interval-valued fuzzy sets, Pythagorean fuzzy sets, hesitant fuzzy sets, and bipolar fuzzy sets. Moreover, some characterizations of bi-ideals, fuzzy bi-ideals, anti-fuzzy bi-ideals, negative fuzzy bi-ideals, Pythagorean fuzzy bi-ideals, and bipolar fuzzy bi-ideals of semigroups are given in terms of the (inf, sup)-type of hesitant fuzzy sets. Also, we characterize a semigroup which is completely regular, a group and a semilattice of groups by (inf, sup)-hesitant fuzzy bi-ideals.

• Communications of the Korean Mathematical Society
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• v.10 no.3
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• pp.653-659
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• 1995

We prove that two essentially normal elements of a type $II_{\infty}$ factor von Neumann algebra are unitarily equivalent up to the compact ideal if and only if they have the identical essential spectrum and the same index data. Also we calculate the spectrum and essential spectrum of a non-unitary isometry of von Neumann algebra.

• Korean Journal of Social Welfare
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• v.64 no.2
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• pp.31-54
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• 2012

Along with increasing mothers' employment, work-family reconciliation has been recognised as a key policy agenda in contemporary welfare states. Although various policy instruments have been introduced and expanded in recent years, the problem of time allocation within couples still remains as a fundamental issue, which has been largely underresearched at a micro perspective. In this context, this study aims to identify dominant types of work-family time allocation within married couple, and to apply these types to the Korean case using the fuzzy-set ideal type analysis. Further, a series of multiple regression analyses will be implemented to find factors affecting each ideal type of work-family time allocation. The 1999 and 2009 Korea Time Use Survey datasets will be adopted for the analyses. Married couples are selected as samples only when men work 40 hours or more per week and they have at least one pre-school child. Empirical analyses cover three parts. First of all, four ideal types on work-family time allocation are classified by intersecting two core variables - the ratio of men's (paid) working and family (caring time plus domestic work) time to total working and family time. In this research, the four types will be labelled the traditional male breadwinner model (TM, high working and low family time), the dual burden model (DB, shared working but low family time), the family-friendly male breadwinner model (FM, high working but shared family time), and the adaptive partnership model (AP, shared working and shared family time). By comparing the composition of the four ideal types in 1999 and 2009, it will examine the trend of work-family time allocation in Korea. In addition, multiple regressions will be useful for investigating which characteristics contribute to the different degree of each fuzzy ideal score in the four models. Finally, policy implications and further research agenda will be discussed.

• Bulletin of the Korean Mathematical Society
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• v.35 no.2
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• pp.259-268
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• 1998

We give several characterizations of a TV-PVMD and we show that the localization R[X;S]$_{N_{\upsilon}}$ of a semigroup ring R[X;S] is a TV-PVMD if and only if R is a TV-PVMD where $N_{\upsilon}\;=\;\{f\;{\in}\;R[X]{\mid}(A_f)_{\upsilon} = R\}$ and S is a torsion free cancellative semigroup with zero.

• Honam Mathematical Journal
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• v.36 no.3
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• pp.605-622
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• 2014

We provide a minimal free resolution for a class of Gorenstein ideal of grade 4 which is the sum of an almost complete intersection J of grade 3 and a perfect ideal I of grade 3 with type 2 and ${\lambda}(I)$ > 0 geometrically linked by a regular sequence, where I is generated by odd elements.

• Journal of the Korean Society of Costume
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• v.63 no.4
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• pp.118-131
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• 2013

The purpose of this study is to take a look at the fashion frame of Korean women in their twenties and thirties to sort the actual fashion image and the ideal fashion image according to the fashion frame of Korean women in their twenties and thirties, and also to find out the standards and features that divide such a classification. For this study, we used the Q method, which is valued as an effective way to assess subjectivity. This helps to objectively classify the perception the fashion images of and the response to them as well. The analyzed materials were divided into two actual fashion frames and two ideal fashion frames, and classified them into 12 fashion image types in total, that is, six actual fashion images and six ideal fashion images, and we named each type of the fashion images and analyzed the features of each fashion image type through the in-depth Q workshop in which 14 professionals participated. The results of this study are as follows: First, the actual fashion frames of Korean women in their twenties and thirties was largely divided into 'Fashion Gold Girl', the fashion frame of mainstream and 'Indi-idol', the fashion frame of subcultures, and this was further divided into six fashion image types: 'Basic Casual', 'Vintage Performer', 'Easy Chic', 'Ladies' Look', 'City Office Girl' and 'Club Mania'. Second, the ideal fashion frame of Korean women in their twenties and thirties was divided into 'Urban Refinement', the fashion frame of the mainstream and 'Mismatched Style', the fashion frame of subcultures. It was also divided into six fashion image types: Power Fashion', 'Fashion Conservative', 'Semi-culture', 'Fashion Otaku', 'Sweet Darling' and 'Fashion Panic'. Third, The characteristics of the fashion images' colors are recognizable according to the type of fashion images.