• Animal Systematics, Evolution and Diversity
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• v.13 no.1
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• pp.21-27
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• 1997

한국 고유종인 새코미꾸리(Cobitis rotundicaudata)의 집단간 유전적 차이에 따른 종 분화 여부를 밝히고자 4개집단을 대상으로mitochondrial DNA(mtDNA)의 RFLP분석을 실시 하였다. C. rotundicaudata mtDNA를 10개의 6-base cutting 제한요소로 처리한 다음 그 절 편 양상을 비교, 분석한 결과 4개 집단 공히 mtDNA의 전체 genome 크기는 약 16.5$\pm$ 0.5Kbp였으며 공통절편수(F)에서 한강 2개 집단(가평, 진부)과 동해안 마읍천 짐단간의 F값 은 0.911로 매우 가까웠으나 낙동강의 산청집단은 타 3개 집단과 F=0.375로 차이가 있었다. 또한 염기치환율(p)에 있어서도 한강 2개 집단 및 마읍천 집단간은 평균 p=0.005로 매우 유 사하였으나, 산청 집단은 타 집단들과 염기치환율에 있어 p=0.059로 종수준의 뚜렷한 차이 를 나타내어서 이들은 각각 별종으로 사료된다.

• The Journal of Korean Association of Computer Education
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• v.9 no.5
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• pp.1-11
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• 2006

This study aims at identifying what effect ARCS model based instruction and cognitive style have on learning motivation and achievement in computer education. In order to accomplish this goal. 70 high school students were randomly allocated into the experiment group and the control group. And each group was divided into field-independent group and field-dependent group. The results were as follows. First, post test of learning motivation among four groups showed that mean differences were statistical significant. Especially 'ARCS model based instruction-field independent group got higher score than 'traditional instruction field dependent' group. Second, post test of learning achievement showed no significant mean difference among four group. The result of the pre and post test difference analysis showed that the change scores of means were significantly different.

• Journal of Korean Society of Forest Science
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• v.44 no.1
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• pp.1-25
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• 1979

Six natural populations of Pinus densiflora S. et Z. as shown in the location map (Flg 1) were studied during 1978. The numerial pouplation codes, 13 to 18. The results of populations 1 to 12 were reported in previous papers. Following the study methods described before, 20 trees were sampled from each population and morpological characteristics such as stem forms, branching habit needle and wood properties investigated. The results are summerized as follows; 1. The mean stand ages were ranged from 36 to 97 of years. The growth performances of trees of population 14. 15 and 18 was similar, but 13, 16, and 17 seemed to be inferior more or less. 2. The ratios of clear bole length were 0.70 in population 18 as the highest but 0.28 for population 16 as the lowest. 3. The population 17 was considered to be a stand of the coarser branching habit having the crown index (The maximum crown diameter/the crown height) 158 though the branching angles were almost horizontal. 4. The differences were observed in the clear bole length ratios and crown-indices between population as shown In Fig. 3 and 4. 5. As to the serration density, number of stomata row and resin duct; the significant differences exist between individual trees within population and also between populations. 6. Population 18 shown resin duct index 0.119 as the maximum. 7. The patterns of diameter growth, based on the width of 10-year-ring segment unit(for example, the 1st segment denotes the with between pith center and 10th year ring and the 2nd one is from 11th to 20th ring and so on.), were alike among populations as shown in Fig 9. 8. Significant differences between population in mean summer wood percentage as well as in wood specific gravity was observed. The values of wood specific gravity were increased with the increase of ages in population 14, 18 however vice versa in population 13, 15, and 17. 9. The fiber length was mereased with the increased of age but no differences between populations as shown in Fig. 12.

• Journal of Convergence for Information Technology
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• v.7 no.6
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• pp.253-258
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• 2017

The purpose of this study is to measure the difference of corporate social responsibility(hereinafter referred to as "CSR") effects on SME's depending on the level of business risk perception. For this aim, we divided the analysis target SEM's into two groups according to the level of business risk perception and examine whether there is any difference in CSR effects through t-test and the test of the structural model invariance across the groups. As a results, the difference of CSR activities between the two groups occurred in the communication and strategy. In terms of CSR effects, there was a gap in the financial performance.

• Korean Journal of Childcare and Education
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• v.9 no.1
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• pp.201-220
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• 2013

This study focused on science activities that need collaborative inquiry process and evaluate the effects of small group's science cooperative learning according to personality types on young children's science activities. The subjects are 30 five-year-old kindergarteners. They have been divided equally into three groups, extroversion(E), interversion(I), and heterogeneous group of EI mixed group depending on EI indicators through K-ABC cognitive ability tests and MMTIC personality types targeting. Both of groups have 10 members each. For data analysis, scientific attitude was analyzed with ANCOVA, scientific knowledge development was done with frequency analysis. As a result, first there was a difference in scientific knowledge development between the homogeneous group and heterogeneity group in small group's cooperative learning. Through the results of a Scheffe post-hoc test, there was a significant difference between E and I homogeneous groups but there was no difference between I homogeneous group and the heterogeneity group, and between E homogeneous group and the heterogeneity group, I homogeneous group had the most effective group composition in scientific attitude improvement.

• Korean Journal of Culture and Social Issue
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• v.15 no.4
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• pp.469-486
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• 2009

This research aims to examine the differences in the christians' self-conscious feelings - shame and guilt-feeling etc. - according to their religious propensity. For this 711 christians were participated. First, we explored the relationship among demographic variables, religious propensity and self-conscious feelings, and then tested the differences in the self-conscious feelings according to 4 religious propensity - pro-religious, intrinsic-religious, extrinsic-religious and non-religious - groups. The result showed that intrinsic religious group is significantly higher in the guilt-feeling than extrinsic religious group, but there were no difference in shame. In conclusion, christian's intrinsic-religious, propensity seemed to relate to mature religious attitudes, but christian's extrinsic-religious propensity to immature attitudes. Finally the implications and limitations of the study, as well as suggestions for the further study were discussed.

• Journal of Korea Port Economic Association
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• v.28 no.4
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• pp.231-255
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• 2012

This study examined the communication and conflict between ship prganization and ship management team. Those are measured and analyzed about both groups, and then the relationships would be investigated objectively and synthetically. Especially, this relationships are enlightened by measuring the level and gap of the communication and group conflict between ship organization and ship management team. The effect of that conflict is analyzed on the organization commitment and job satisfaction of ship organizations. As a result, this study demonstrates the communications have a negative influence on group conflict with statistic significance, also the conflicts effect negatively on the organization commitment and job satisfaction. In the analysis of gaps about the communication and conflict between groups, the level of group conflict is lowest in the group whose gap of communication is small and both communications are activated, and the organization commitment and job satisfaction are highest in the group whose gap of group conflicts is small and both level of the conflicts are low. To conclude, the ship organization and ship management teams in the shipping company have to lessen their conflict each other and heighten the organization commitment and job satisfaction through their smooth communication.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.1008-1018
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• 2014

The purpose of this study is to investigate whether there are differences in academic self-efficacy and test anxiety between two groups(depending on gender and English achievement levels) of Korean middle school students. The subjects are 98 students who are 36 male and 62 female students. Two Questionnaires were administered to measure the learners' academic self-efficacy and test anxiety level. And the collected data were analyzed by t-test to examine the differences between two groups. The results of this study showed that there were statistically very significant differences in academic self-efficacy and test anxiety between two(male-female) groups. But there were no differences statistically in academic self-efficacy and test anxiety between two(high level-low level) groups. Further studies need to be conducted carefully considering the limitations of this study in terms of its instruments and subjects. Also the differences in other affective variables between two groups need to be studied in the future.

• Communications of Mathematical Education
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• v.11
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• pp.159-170
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• 2001

본 연구의 목적은 개방형 교수법에 의한 수업이 수학적 문제해결력과 신념 형성에 미치는 효과를 분석함으로써 수학 교수방법의 개선에 도움을 주는 데 있다. 본 연구를 통하여 얻은 연구 결과는 첫째, 개방형 수업 집단과 일반적 수업 집단간에 문제해결력에 있어서 유의미한 차이가 있었으며, 둘째, 개방형 수업 집단과 일반적 수업 집단간에 수학적 신념에 있어서도 유의미한 차이가 있었다. 본 연구의 결과를 통하여, 개방형 교수법에 의한 수업은 일반적 수업보다 문제해결력 및 수학적 신념 수준을 향상시킬 수 있는 교수법임을 시사한다.

• Journal of Korean Society of Forest Science
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• v.42 no.1
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• pp.1-38
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• 1979

The woody species of Genus Ilex which are endemic to Korea are distributed on limited area due to solely temperature factor. There is some differences according to species, however in general, the evergreen Ilex are found along southern coastal area of Korean Peninsula and near islands where the cold index does not exceed $-5^{\circ}C$. But Ilex macropoda and the variety, only deciduous ones, are grown in temperate zone of the peninsula and some islands. The list of Ilex species of Korea are as follows. Ilex cornuta Lindley et Pax., I. crenata Thunb. var. microphylla Max., I. crenata Thunb., I. rotunda Thunb., I. macropoda Miq., I. macropoda Miq. var. pseudo-macropoda Loensner, I. integra Thunb. The author surveyed the populations of Ilex species as many as possible and data of some characters such as leaf shape, spine, fruit shape, stomata density, sex ratio in natural communities, etc. are collected. Almost all the Ilex species in Korea show sporadic distribution. This means quite small sized populations isolate distantly each other eliminating the change of gene exchange in between. Particularly Ilex conuta and I. crenata show the morphological differentiation among populations as well as significant individual variation within a population. These were true with such characteristics, leaf shape, leaf dimension, leaf margin, fruit shape, spine, and stomata density. The founded are that the fruit length and the stomata density counted on the beneath surface of leaves of Ilex cornuta increased with the decrease of latitude. These are naturally closely related with the cold index values. The table shown below indicates the correlation between mean stomata density per $0.3642mm^2$ and cold index values. These relation however were not observed on Ilex crenata. The most dominated natured in relation to individual variation were outline of leaf, the number of marginal spine, the shape of leaf cross section and the degree of luster of the upper leaf surface. As shown in photos 5~7, these variations are agreed at a glance. There are reports that the development of marginal spines in some Ilex species is associated with the juvenility and topophysis. In present study, these two factors were neglected because of the intended sampling procedure. Of Ilex rotunda, population difference with the characteristics of leaf length is recognized but not for leaf width, petiole length, and fruit size. However, individual variations within a population were significantly large. In case of Ilex integra, only individual differences within population were calculated statistically for such characteristics as leaf length, leaf width, and petiole length. As to natural population, the sex ratio was 1:2 (female to male) for Ilex cornuta, and 1:1 for Ilex crenata. The tendency of more male than female in I. cornuta was agreed to other observations. Preparing the tip cutting of length 10cm, and treating with IBA, then attaching earth ball to the cut end, very successful rooting percentages were obtained. Asexual propagation has the advantages of maintaining the heterozygosity of existing varieties and overcoming the difficulties of delayed seed germination frequently encountered with Ilex species. Considering a great deal of variation in morphological traits, a good possibility of selection breeding for decorative and ornamental purposes exists. At present, these evergreen Ilex are ignored by local people as nuisance weedy shrubs. So the proper protection measures should promptly be taken.