• Korean Journal of Comparative Education
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• v.28 no.5
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• pp.1-19
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• 2018

The purpose of educational assessments such as the Trends in International Mathematics and Science Study (TIMSS) is to compare groups such as countries. When the unit of measurement is above the student level, group-level diagnostic assessment based on multilevel item response theory (ML-IRT) can be considered just as cognitive diagnosis models are developed from item response theory. This study suggests an ML-IRT-based group-level diagnostic assessment model by modifying an item feature model by Park and bolt (2008). The model is illustrated on the recently released TIMSS 2015 Grade 8 mathematics assessment. The results provide skill profiles for the studied countries and the nine cognitive attributes; that is, the attribute effects can be compared across the countries and also across the attributes. By controlling unexplained variance, the suggested model may provide more reliable and more informative group-level comparisons. The results are interpreted using an example. Limitations and directions for future research are also discussed.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.05a
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• pp.189-194
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• 2000

본 연구에서 면대면과 CMC상황에서 기저율과 개별정보를 통합해야하는 과제를 집단으로 결정하는 과제를 수행한 후, 집단 구성원들은 자신의 의견과 집단의 의견에 관해 다른 확신 수준을 보임을 발견하였다. 면대면 집단의 구성원이었던 사람들은 자신은 기저율과 개별정보를 둘 다 적게 사용하였지만 자신의 집단은 이 두 가지 정보를 모두 많이 사용하였다고, 지각하였으며, CMC집단의 구성원이었던 사람들은 자신과 자신의 집단이 유사한 정도로 기저율과 개별정보를 사용하였다고 지각하였다. 본 연구에서는 면대면 집단 조건에서는 집단 극화가 발생하였지만, CMC집단의 경우에는 오히려 억제되는 결과를 보였다. 이는 기존의 연구에 비추어 볼 때, 토론 시간의 부족에 기인한 것으로 고려되어지며, 추가 연구를 통해 더 많은 시간이 주어질 때 이 두 집단간에 어떠한 차이가 발생하는지 알아보고자 한다.

• The Korean Journal of Zoology
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• v.35 no.4
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• pp.497-504
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• 1992

한국특산종인 Colitis rotundicuudutu의 지리적 변이를 전국 5개 집단 132개체를 대상으로 조사하였다. 4개 집단의 계측형질로 본 다변량분석 결괴 산청집단은 타 집단과 형태적 차이가 있었다 전기영동으로 조사된 5개 집단의 평균 유전적 변이 정도는 A=1.48, P=37. IpA, HD=0. 139, 및 H6=0. 124로 변이 정도가 타 어류에 비하여 비교적 높았다. 5개 집단의 평균 유전적 근인치(S)는 0.83으로 낮았으나 산청집단을 제외한 4개 집단의 근연치는 0. 91로 매우 가까웠다. 반면 산청집단은 나머지 집단과 형태적으로나 유전적으로 유의한 차이가 나타나는 것으로 보아 산청집단의 별종 가능성이 매우 높음을 시사한다. 앞으로 보다 면밀한 연구로 산청집단의 별종 여부를 명백히 구명하여야 할 것이다.

• Journal for History of Mathematics
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• v.24 no.4
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• pp.157-180
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• 2011

This paper analyzed about gender difference in the achievement of underachievers of high school students while learning using technology. Participants were composed of 67 underachievers on first grade in high school located in a metropolitan city. That had never used a mathematics educational calculator before. Target participants were divided into two groups: experiment group that studied activity papers with a CAS calculator. And control group that studied the same activity papers using only paper-and-pencil. The content of the activity papers for the two groups was the same, but the structure differed. The two groups completed mathematics achievement tests both before and after the activity papers. The results are that find out no difference of the mathematics achievement between boys and girls in each group, and that the mathematics achievement of boys in experiment group are better than one of boys in control group, and also girls.

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.221-226
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• 2009

Six microsatellite DNA markers were used to investigate the genetic variability between wild populations and cultured stocks of olive flounder Paralichthys olivaceus. The average of observed (Ho) and expected heterozygosity (He) ranged from 0.722 to 0.959, and from 0.735 to 0.937, respectively. There was no distinguishable difference between the wild populations and cultured stocks in terms of the observed and expected heterozygosities. However, number of alleles per locus differed markedly between the two fish groups: 19.7 to 21.8 for the wild populations and 12.0 to 14.7 for the cultured stocks. This result gives important information concerning the production of seedling for the improvement of genetic diversity in this species.

• Journal of Korean Society of Forest Science
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• v.95 no.4
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• pp.435-442
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• 2006

A total of 167 peculiar haplotypes confirmed from 28 cpSR variants that were observed in 19 populations of Japanese red pine in Korea through cpSSR marker analysis. Thirteen individuals that showed identical haplotype dispersed evenly in 10 populations, and the average number of effective haplotype within population was 13.37. Estimate of genetic diversity (He) was 0.987 on the basis of cpSSR haplotype variants that was equivalent to or higher than the estimates reported in other studies on some forest tree species. Estimation of genetic diversity (S.I.) on the basis of cpSSR variants composing each haplotype revealed the highest estimate of 1.109 for the population of Gangwon-Yeongwol and the lowest estimate of 0.411 for the population of Gyeongbuk Mungyeong with the average of 0.887. Most of observed cpSSR variants appeared to exist commonly in 19 populations (97.62%), and genetic differentiation of cpSSR variants among populations was turned out to be weak (${\Phi}_{ST}=0.024$). Relatively fast rate of mutation of cpSSR marker might be a major cause for such weak population differentiation. There was no identical haplotype shared between 39 population pairs of 173 pair-wise population pairs. Estimation of genetic distance among 19 populations on the basis of population pairs was also impossible, that might be resulted from restricted migration among 19 populations. Considering the observed distribution patterns of cpSSR variants in addition to the previous studies on I-SSR variants, informations on the present geographic location and genetic status of populations should be considered together for effective sustainable management of the genetic resources of Japanese red pine in Korea.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.11a
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• pp.419-422
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• 2007

유전자 변이가 쉽게 일어나는 바이러스 등은 변이 계통에 따라 집단을 형성하게 된다. 이러한 집단들에 대한 분석은 해당 바이러스 집단에 대한 추적, 백신 및 치료약 개발에서 필수적이다. 어떤 집단의 염기 서열의 특성을 효과적으로 표현하는 패턴을 시그너쳐라 하며, 이러한 시그너쳐는 특정 염기서열 집단의 고유한 특성을 나타내면서 다른 집단과 구별되는 정보를 포함하는 것이 바람직하다. 이 논문에서는 가능한 후보 시그너쳐들을 염기분포를 이용하여 생성해가면서, 시그너쳐 해당부위의 염기를 상대 서열집단의 공통 서열의 염기로 변환하여 집단간의 상대거리를 측정함으로써, 후보 시그너쳐에 의한 집단의 고유성질 표현능력과 집단간 차별화 능력을 고려하여 시그너쳐를 추출하는 방법을 제안한다.

• Journal of Music and Human Behavior
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• v.4 no.2
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• pp.18-40
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• 2007

The purpose of this study was to verify the influence of musical activities on social and emotional behavior of infants, through providing musical activities to the infants who were cared in a nursery and observing the interactions between peer group, or a therapist and an infant derived during them. The subject is 24 infants who are under 2 years of age(25~36months) at two nurseries located in Bundang area, and 13 infants among them are randomly assigned as study group and 11 infants as control group. Pretest and posttest about social and emotional behavior are performed, and ITSEA developed by Brggs-Gowan and Carter(2001) and amended by Shin Ji Yeon(2004) was used as an evaluation tool. Infants' changes of interaction behaviors during musical play were also analyzed quantitatively and qualitatively, and for the analysis, infant's social play behavior examination tool developed by Holloway and Reichhart-Erickson(1988) was adopted. Based on time sampling method, each item of this tool was evaluated. Each session was performed for 15 minutes, and 60 times of analysis about interactions per session was conducted at every 15 seconds. The analysis result was showed with a table and a graph, and described qualitatively about behavior changes. When compared social and emotional positive behavior average figures and negative behavior average figures between study group and control group, this study showed that the positive behavior figure of study group was increased and the negative behavior figure was decreased. While concentration and empathy among positive behaviors increased meaningfully, aggression, defiance, separation anxiety and rejection to new things among negative activities also decreased meaningfully. The conclusion of this study is as follows. First, interactions with peers or a therapist based on music and musical experience make an effect on strengthening positive behavior among social and emotional behavior and decreasing negative behavior. Second, music has influence on negative behaviors more than positive behaviors of an infant, and produces a good effect on sub behaviors of negative behaviors specially.

• Journal of Music and Human Behavior
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• v.6 no.2
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• pp.1-23
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• 2009

This study aims to identify the effect of music psychotherapy on motivation for learning in the underachieving student. The study divided nine children into two groups and placed four children in a test group and five children in a control group. After conducting a pre-test, the researcher performed music psychotherapy with the four children in the test group for about 12 weeks, twice a week, totaling 18 sessions. Quantitative data were measured in pre-and-post tests using Mann-Whitney's U-test, and the effects of the therapy were analyzed using Wilcoxon. The findings of this study were as follows. Music psychotherapy was shown to be effective for improving all types of motivation for learning in underachieving students (p < .001). This was shown by assessing improvements in the experimental group across four sub-areas of motivation for learning (p < .1), and directly measured by examining the subjects' lingual responses related to motivation for learning. These results demonstrate that music psychotherapy is effective for enhancing motivation for learning in underachieving students.

• Journal of The Korean Association For Science Education
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• v.22 no.3
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• pp.508-516
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• 2002

This study investigated the influences of group composition in cooperative computer-assisted instruction (CAI) upon students' conceptual understandings, application abilities, learning motivations, and the perceptions of involvement. Seventh graders (N=97) were selected from a co-ed middle school in Seoul, and taught about 'motion of molecules' for 5 class hours. In the two treatment groups with cooperative CAI strategy, homogeneous and heterogeneous small groups were organized by the previous science achievement. Traditional instructions were administered to the comparison group. Two-way ANCOVA results revealed that the scores of the conception test for the treatment groups were significantly higher than those for the comparison group. However, there was no difference between the homogeneous and the heterogeneous groups. The scores of the three groups did not differ significantly in the application test and the learning motivation test. However, the perceptions of involvement for the treatment groups were more positive than those for the comparison group.