• Journal of the Korean Mathematical Society
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• v.56 no.1
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• pp.67-80
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• 2019

For positive integers a, b, c, and an integer n, the number of integer solutions $(x,y,z){\in}{\mathbb{Z}}^3$ of $a{\frac{x(x-1)}{2}}+b{\frac{y(y-1)}{2}}+c{\frac{z(z-1)}{2}}=n$ is denoted by t(a, b, c; n). In this article, we prove some relations between t(a, b, c; n) and the numbers of representations of integers by some ternary quadratic forms. In particular, we prove various conjectures given by Z. H. Sun in [6].

• Child Studies in Asia-Pacific Contexts
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• v.1 no.1
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• pp.25-38
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• 2011

The purpose of this study is to examine the attachment representations of Korean immigrant mothers in America. The subjects were 25 first-generation Korean immigrant mothers who reside in Los Angeles. The Adult Attachment Interview (George, Kaplan, & Main, 1985) was used for assessing their attachment representations. As a result, 36% of the mothers were classified as secure-autonomous (F), 52% as insecure-dismissing (Ds), and 12% as insecure-preoccupied (E). It was concluded that there were lower rates of the secure type among Korean immigrant mothers who had immigrated to the U.S. during the 70's and 80's and higher rates of the dismissing type compared to mothers in South Korea.

• Bulletin of the Korean Mathematical Society
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• v.45 no.1
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• pp.33-37
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• 2008

Let G be a compact abelian Lie group, and M an odd-dimensional closed smooth G-manifold. If the fixed point set $M^G\neq\emptyset$ and dim $M^G=0$, then G has a subgroup H with $G/H{\cong}\mathbb{Z}_2$, the cyclic group of order 2. The tangential representation $\tau_x$(M) of G at $x{\in}M^G$ is also regarded as a representation of H by restricted action. We show that the number of fixed points is even, and that the tangential representations at fixed points are pairwise isomorphic as representations of H.

• Korean Journal of Child Studies
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• v.32 no.5
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• pp.29-47
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• 2011

The purpose of this study was to examine the effects of spousal attachment, spousal caregiving, and parental caregiving behaviors on children's parental representations. One hundred and fifteen preschoolers (72 boys and 43 girls, aged between 4-5 years old) and their fathers and mothers participated in this study. The instruments used were the MacArthur Story-Stem Battery (Bretherton, Oppenheim, Buchsbaum, Emde, and the MacArthur Narrative Group, 1990), the Experiences in Close Relationships Scales (Brennan, Clark, & Shaver, 1998), the Caregiving Questionnaire (Kunce & Shaver, 1994), and the Parental Acceptance-Rejection Questionnaire (Rohner, 1991). The data were analyzed using descriptive statistics and structural equation modeling analysis. In conclusion, parents' spousal attachment, spousal caregiving, and parental caregiving behaviors have influenced on children's parental representations.

• Journal of Korean Elementary Science Education
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• v.39 no.2
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• pp.204-218
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• 2020

This study aims to investigate the representation patterns used by elementary teachers and their meaning-making process in electromagnetic experiments. In particular, we analyzed the representations depending on three levels of their abstractness: enactive representation (action based), iconic representation (image based) and symbolic representation (language based). For this, four experiment activities of two teachers were analyzed and the results are as follows. First, as an overall pattern of representation, an experiment subject is presented as the form of symbolic representation and the related concepts, experimental materials and methods are embodied through iconic representation. Then, through enactive representation, the actual experiments are implemented. The experimental results are primarily recorded through iconic representations and abstracted into symbolic representations to draw conclusions. The different levels of representations complement each other to expand their meanings, however, sometimes they also make inconsistent meanings among different levels. Based on these results, educational implications were discussed in terms of supporting and improving electromagnetic experiment activities.

• Korean Journal of Child Studies
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• v.26 no.6
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• pp.89-110
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• 2005

Subjects were 66 3- to 4-year-old-Children of unemployed mothers from upper middle class families. Attachment behaviors were measured with the Preschool Strange Situation(Cassidy and Marvin, 1992) and classified as secure, avoidant, dependent, or disorganized. Narrative representations of mothers by Children were obtained by video taped interviews using the MacArthur Story-Stem Battery and coded by the MacArthur Narrative Working Group(1997) system. Data were analyzed with descriptive statistics and t test. Results were that children in the secure group showed more positive representations of their mothers, more prosocial story themes, had higher scores in theme coherence and showed more positive emotional expression than those in the insecure group. The attachment behaviors of the 4 groups(A, B, C, D) were closely correlated with the attachment representations shown in MSSB.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.282-285
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• 2000

Three representations are known to implement the discrete wavelet transform (DWT) ; i.e., direct, lifting and matrix forms. In these representations, direct and lifting forms are well known so far. This paper derives the matrix form of the DWT from the direct form. Then, we implement these three representations on a programmable digital signal processor (in the following, DSP processor) and compare them in terms of the number of calculations and instruction cycles. As a result, we confirm that the lifting form has the lowest number of calculations and cycles, and the matrix form has an effective decrease in the number of cycles than other representations on the DSP processor.

• Korean Journal of Child Studies
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• v.21 no.4
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• pp.143-158
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• 2000

This study examined whether children's peer representations are associated with peer acceptance and whether attributions and goals are related to representations about behavioral responses in ambiguous provocation and conflict situations. The subjects were 119 5th-grade children responded to 4 hypothetical situations. Results indicated that children's positive representations about peer conduct in ambiguous provocations were related to their higher level of peer acceptance, and positive representations about a friend in conflict situations were associated with their perceived positive qualities of friendship. Children's positive attribution and relational goal orientation were associated with relational behavioral responses. Gender differences were found for some goals and behavioral responses, with girls displaying a more relational goal and behavioral response orientation than boys.

• ETRI Journal
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• v.29 no.5
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• pp.619-632
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• 2007

Side channel attacks are a very serious menace to embedded devices with cryptographic applications. To counteract such attacks many randomization techniques have been proposed. One efficient technique in elliptic curve cryptosystems randomizes addition chains with binary signed digit (BSD) representations of the secret key. However, when such countermeasures have been used alone, most of them have been broken by various simple power analysis attacks. In this paper, we consider combinations which can enhance the security of countermeasures using BSD representations by adding additional countermeasures. First, we propose several ways the improved countermeasures based on BSD representations can be attacked. In an actual statistical power analysis attack, the number of samples plays an important role. Therefore, we estimate the number of samples needed in the proposed attack.

• Korean Journal of Child Studies
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• v.26 no.4
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• pp.125-143
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• 2005

This study focused on the importance of the attachment/caregiving system at a dyadic level, and examined relationships between maternal representations of caregiving, maternal caregiving behavior, and child attachment. Seventy-five middle-class mothers and their preschool children(ages 3-4) participated in the study. Results indicated a strong correspondence between maternal representations of caregiving and maternal caregiving behavior at the secure/insecure and ordered/disordered level. The correspondence between maternal representations of caregiving and their preschooler's attachment, and between maternal caregiving behavior and their preschooler's attachment at the secure/insecure level were also strong. The correspondence between maternal representations of caregiving and their preschooler's attachment was mediated by maternal caregiving behavior.