• Communications of the Korean Mathematical Society
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• v.24 no.4
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• pp.501-508
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• 2009

This paper presents a new representation algorithm which computes the representation for elements of a free group generated by two linear fractional transformations and also the justification of the algorithm in order to show how it operates correctly and efficiently according to inputs.

• Communications of the Korean Mathematical Society
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• v.11 no.3
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• pp.547-555
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• 1996

In this paper, we shall study the generalized covering group which plays a role for Schur multiplier. We discuss the lifting property over covering group and product of covering groups.

• Human Ecology Research
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• v.57 no.1
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• pp.41-50
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• 2019

This study investigated the significant difference in the influences of pregnant couples' attachment representation for parents of origin on their psychological symptoms according to groups. One hundred and eighty two pregnant couples answered the questionnaire. Data were analyzed by means of frequency, percentages, t-test. Pearson's correlation using SPSS ver. 21.0 and multiple group structural equation modeling using AMOS ver. 20.0. The findings are as follows. First, there were significant differences in attachment representations according to parents of origin and psychological symptoms between pregnant women and spouses. Second, there were negative influences of attachment representations to parents of origin on psychological symptoms for both the pregnant women group and their spouses group, respectively. Last, the negative effects of attachment representation for parents of origin on their psychological symptoms according to groups were significantly different; consequently, the impact on the spouses group was stronger than the pregnant women group. The results imply that policies to help pregnant couples reduce psychological symptoms should be provided. In addition, the unexpected result on the weaker impact of pregnant women's attachment representation for parents of origin on their psychological symptoms suggests it is better to consider other factors simultaneously (such as a romantic attachment to spouses) that might provide a moderating role. The study results are meaningful because it is the first to apply a statistically advanced method to analyze pregnant women and spouses in relation to parents of origin on their psychological symptoms.

• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.500-508
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• 2012

The purpose of this study was to investigate the impact of multimodal representation-based lesson on embeddedness of multimodal representation in high school students' writing. The participants in this study were two groups of second-year science-track students (74 students) at an academic high school in a metropolitan city. One group (41 students) was assigned to the experimental group, the other group (33 students) was assigned to the comparative group. Data analysis showed that the students of the experimental group were better at utilizing and embedding multimodal representations. Thus, the conclusion was drawn that multimodal representation-based lesson had an effect on high school students' embeddedness of multimodal representation.

• Journal of the Chungcheong Mathematical Society
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• v.16 no.2
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• pp.59-73
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• 2003

Throughout this paper, we denote that R is a near-ring and G an R-group. We initiate the study of R-substructures of G, representations of R on G, monogenic R-groups, faithful R-groups and faithful D.G. representations of near-rings. Next, we investigate some properties of monogenic near-ring groups, faithful monogenic near-ring groups, monogenic and faithful D.G. representations in near-rings.

• School Mathematics
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• v.5 no.3
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• pp.361-384
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• 2003

The purpose of this study was to investigate students' problem solving process based on the model of IDEAL if they learn to solve word problems of simultaneous linear equations through structure-representation instruction. The problem solving model of IDEAL is followed by stages; identifying problems(I), defining problems(D), exploring alternative approaches(E), acting on a plan(A). 160 second-grade students of middle schools participated in a study was classified into those of (a) a control group receiving no explicit instruction of structure-representation in word problem solving, and (b) a group receiving structure-representation instruction followed by IDEAL. As a result of this study, a structure-representation instruction improved word-problem solving performance and the students taught by the structure-representation approach discriminate more sharply equivalent problem, isomorphic problem and similar problem than the students of a control group. Also, students of the group instructed by structure-representation approach have less errors in understanding contexts and using data, in transferring mathematical symbol from internal learning relation of word problem and in setting up an equation than the students of a control group. Especially, this study shows that the model of direct transformation and the model of structure-schema in students' problem solving process of I and D stages.

• Korean Journal of Child Studies
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• v.32 no.4
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• pp.63-81
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• 2011

The purpose of this study was to examine the first generation Korean-American mothers' attachment representation as well as the attachment representation of their second generation Korean-American college students. The subjects consisted of 25 first generation Korean-American mothers and 27 second generation college students residing in Los Angeles. The Adult Attachment Interview (George, Kaplan, & Main, 1985) was used for assessing attachment representation patterns. The results of this study were as follows. First, 36% of the subject mothers were classified as secure, 64% were insecurely attached and there was no unresolved/disorganized pattern in the insecure group. Second, 33% of the subject students were classified as secure. 67% were insecure on the AAI, and there was 4% unresolved/disorganized patterns in the insecure group. Third, a difference of 76% was found between the correspondence between the first generation Korean-American mothers' attachment representation pattern and the attachment representation of the second generation Korean-American college students.

• Kyungpook Mathematical Journal
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• v.49 no.1
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• pp.7-14
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• 2009

In this short note, we consider a family of linear representations of the braid group and the fundamental group of a punctured torus bundle over the circle. We construct an irreducible (special) unitary representation of the fundamental group of a closed 3-manifold obtained by the Dehn filling.

• Journal of the Korean Mathematical Society
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• v.34 no.3
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• pp.673-693
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• 1997

In this work, the irreducible complex representations of degree 4 of $B_4$, the braid group on 4 strings, are classified. There are 4 families of representations: A two-parameter family of representations for which the image of $P_4$, the pure braid group on 4 strings, is abelian; two families of representations which are the composition of an irreducible representation of $B_3$, the braid group on 3 strings, with a certain special homomorphism $\pi : B_4 \longrightarrow B_3$; a family of representations which are the tensor product of 2 irreducible two-dimensional representations of $B_4$.

• Korean Journal of Child Studies
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• v.26 no.6
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• pp.247-266
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• 2005

Subjects of this study were 621 children selected from 5th and 6th grades of elementary schools in Pusan. Factors associated with parents and peers varied by type of peer maladjustment(aggressive type and withdrawn type, compared with a control group). Particularly, the level of factors associated with peers varied from the control group by peer maladjusted types(aggressive types and, withdrawn types). Causal relationships of parents' rejection, victimization, negative representation by parents and by peers on child？s maladjustment varied by behavior types. Negative representation of peers had a direct effect only on withdrawal. On the other hand, negative representation of peers had no effect on aggression. Victimization had a first total effect on both withdrawal and aggression.