• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.12
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• pp.1801-1810
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• 2016

The OpenDaylight controller has been receiving significant attention as one of the enabling open source framework for SDN, and this paper analyzes the architecture and procedure of OpenDaylight based controller cluster. The OpenDaylight controller cluster uses shard based distributed datastore and Raft algorithm to maintain consistency among controllers inside a cluster. The performance evaluation analyzes the leader re-election time as well as latencies of CRUD and Routed RPC according to cluster size, shard role, and sharding strategy, and we discuss the optimal operation strategy for OpenDaylight controller cluster.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.5
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• pp.547-558
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• 2004

The purposes of this study were to classify shopper types based on clothing shopping orientations and to identify the differences in store selection criteria and demographic characteristics by shopper types. The questionnaire was administered to female and male undergraduate and graduate students living in Seoul. Of 330 returned questionnaires, 319 were used in the statistical analysis which were factor analysis, cluster analysis, $\chi$$^2$-test, and One-way ANOVA. The results of this study were as follows: 1) Clothing shopping orientations had six factors: recreational shopping, name conscious shopping, economic shopping, fashion oriented shopping, convenience shopping. and individualistic shopping. Cluster analysis identified that clothing shopping orientations had four groups: recreational cluster, individualistic cluster, demanding shopper cluster, and convenient brand conscious shopper cluster. 2) Clothing shopping orientations were significantly different in relation to the demographic characteristics such as gender, major field of study, expenditure on clothing, pocket money, and family income level. 3) Store selection criteria had five factors: service quality, physical store environment, sales personnel, shopping convenience, and other attractions. 4) There were significant differences in physical store environment, shopping convenience, and other attractions according to the shopper clusters.

• Journal of the Korean Geographical Society
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• v.44 no.5
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• pp.634-646
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• 2009

This paper critically examines cluster dynamics and development in a multi-scalar approach, criticizing both the argument overemphasizing local networks and endogenous development for regional development and the contention highlighting global networks and the role of global players. We argue that state policies, exogenous and direct, play a significant part in cluster dynamics and development especially in the case of Korea where the state government's strong policies have led to rapid industrialization. We analyze multi-scalar factors, especially the government policies at a national level, in the development paths of the three cases including Ulsan automobile cluster, Daedeok research cluster, and Dongdaemun fashion cluster.

• Development and Reproduction
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• v.18 no.2
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• pp.89-98
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• 2014

The twenty-one individuals of Meretrix lusoria were secured from Gunsan, Shinan and Yeonggwang on the coast of the Yellow Sea and the southern sea in the Korean Peninsula, respectively. Amplification of a single COI fragment (720 bp) was imagined, and no apparent size differences were observed in amplified fragments between Meretrix lusoria and M. petechialis individuals. The size of the DNA fragments also varied excitedly, from 200 to 1,600 bp. The oligonucleotides primer BION-08 produced the least loci (a total of 17), with an average of 2.43 in the Gunsan population, in comparison to the other primers used. Remarkably, the primer BION-13 detected 42 shared loci by the three populations, major and/or minor fragments of sizes 200 bp and 400 bp, respectively, which were identical in all samples. The dendrogram gained by the seven oligonucleotides primers highlight three genetic clusters: cluster 1 (GUNSAN 01 ~ GUNSAN 07), cluster 2 (SHINAN 08 ~ SHINAN 14) and cluster 3 (YEONGGWANG 15 ~ YEONGGWANG 21). The longest genetic distance among the twenty-one Meretrix lusoria individuals that displayed significant molecular differences was between individuals GUNSAN no. 01 and SHINAN no. 14 (genetic distance = 0.574). Comparatively, individuals of SHINAN population were fairly closely related to that of YEONGGWANG population. In this study, PCR analysis has discovered significant genetic distances between two white clam population pairs (P<0.05).

• The Korean Journal of Community Living Science
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• v.24 no.4
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• pp.553-565
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• 2013

The purpose of this study is to segment urban farming patterns and analyse the preference on urban farming by applying two-step cluster analysis, chi-square analysis and ANOVA. The data was collected by face-to-face surveys on 9 urban farms which were chosen by location and operator. Respondents were asked to describe their urban farming pattern, preference on urban farming and socio-demographic characteristics. Three different clusters were derived from two-step cluster analysis based on operator, transportation, number of visits per month, travel time, area and motive. They were 'hobby-oriented farming', 'producing-oriented farming', and 'multipurpose farming'. The results of chi-square analysis showed that there were significant differences among these three segmented groups in terms of age, with or without children aged under 14, household income per month and housing type. In other words, there is quite a possibility that urbanites have different urban farming patterns according to their socio-demographic profiles. Also, there were significant differences on the preference on urban farming by cluster. According to the results, planning directions of urban farming were presented.

• Korea Journal of Hospital Management
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• v.9 no.1
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• pp.95-114
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• 2004

The purpose of this study was to identify the relationship between organizational culture based on the competing values approach, human resource management practices and organizational performance at a hospital. Participants were 138 employee in a general hospital. Data were collected during May, 2003 using four structured instruments. The data were analyzed using Chi-square test, One-way ANOVA, $scheff{\acute{e}}$ test and Cluster analysis. Three clusters were derived from cluster analysis. The first cluster consisted of cultures which were mixed developmental, consensual, hierarchial and rational culture equivalently. The second cluster consisted of the weak cultures, which was lower score than other clusters. The third cluster consisted of strong comprehensive cultures, which had higher score than other clusters. In the three clusters, hierarchial and rational culture were superior. The difference between human resource management practices and organizational commitment in organizational performance according to organizational culture clusters was found to be statistically significant. The cluster which had strong comprehensive cultures, in contrast to other clusters, more significantly affects on human resource management practices and organizational commitment. However, the strength of organizational culture does not have a significant effect on customer oriented service performance in organizational performance. These results showed that types of organizational culture were significantly related to human resource management practices and organizational commitment, and understanding the existing culture is essential to develop the organization of hospitals.

• Korean journal of food and cookery science
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• v.23 no.3 s.99
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• pp.327-336
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• 2007

Life-style factors often include social relationships as well as consumption, entertainment and dress patterns. They also typically reflect an individual's attitudes, values and worldview. Life-style types have become and an important factor for segmenting customer markets ever since significant relationships between life-style and customers' behavior was proven. This study examined the relationships between the life-styles of young customers' and the important attributes of foodservice encounters. Factors analysis with VARIMAX and K-means cluster analysis were conducted to group the subjects by life-style. According to the factors analysis, four underlying dimensions were identified and labeled: (1) 'actively fashioned', (2) 'luxury picky', (3) 'healthy toward', and (4) 'utilitarian leisure'. Based on the factor scores derived from the factors analysis, the K-means cluster analysis classified three groups as statistically significant using ANOVA(p<0.05). The overall mean score for the 3rd cluster 'trendy-active picky' was higher than the other two clusters, and represented very picky attitudes about foodservice attributes. The 3rd cluster also seemed to apply higher standards to all of the foodservice attributes. By order of importance, the most important attributes of the 2nd cluster 'pursue-utilitarian leisure' were food serving time, automation systems, server's hygienes, employee kindness, time in line, and menu variety. In spite of low concerns for the life-style attributes, the first cluster 'passively indifferent' recognized menu variety, food sanitation, food serving time, server's hygiene, menu price, air circulation, and room temperature as important. These results suggest that young diners in Korea could be classified by their diverse life-styles that are represented as trendy, utilitarian, and indifferent and will hopefully contribute to the foodservice industry's ability to segment customer characteristics by different life-styles in Korea.

• Journal of Korean Elementary Science Education
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• v.25 no.spc5
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• pp.495-506
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• 2007

This study investigated the differences in learning activity preferences according to different thinking styles between gifted and average students. A cluster analysis procedure was performed to classify students on the basis of thinking styles. Two clusters of different thinking styles were deduced: the gifted group with a high level thinking style (cluster 1), and the average group with a low level thinking style (cluster 2). The gifted group (cluster 1) preferred projects, simulations, discussions and game activities to other types of loaming activities. Gifted students and average students also were clustered into each three unique subgroups with respect to levels and patterns in thinking styles, and these subgroups also showed different learning preferences. The clusters of gifted students included the self-regulated learning type (cluster a), cooperative-learning type (cluster b), and the passive-learning type (cluster c). The clusters of average students included the independent learning type (cluster i), no-preference learning type(cluster ii), and the no-motivation & teacher-directed learning type (cluster iii). Theses clusters indicated significant differences not only in thinking styles but also in terms of preferences regarding learning activities. Theses findings are discussed in terms of their educational implications.

• Plant Resources
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• v.6 no.3
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• pp.178-182
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• 2003

This study was conducted to investigate the relationship between yearly variations of climatic elements and yearly variations of productivity in perilla. In addition, correlation coefficients among yield and yield components were estimated. The data of yield and yield components were investigated for 10 years from 1991 to 2000. The meteorological data gathered at the Yeosu Weather Station for the same period were used to find out the relationships between climatic elements and productivity. Yearly variation of the amount of precipitation in September was large with coefficients of variation(c. v.) of 11.1%, but the coefficient of variance(c. v.) in July and August were relative small with 1.8, 2.1%, respectively. Number of cluster per hill and weight of 1,000 grains were greatly with c. v. of 76.1, 79.3%, respectively, but the coefficients of variance(c. v.) of plant height and seed yield were more less with 9.58, 10.60%, respectively. Correlation coefficients between precipitation of September and seed yield were positively significant correlation at the level of 5.1%, respectively, but the duration of sunshine in September and seed yield were negatively significant at the level of 5.1%, respectively. Correlation coefficients of these, the plant height, number of branches per plant, cluster length, number of cluster per hill, weight of 1,000 grains and seed yield were positively significant at the level of 5.1% respectively.

• Journal of Engineering Education Research
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• v.22 no.5
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• pp.20-28
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• 2019

This study examined the relationships among grit, life goal, and conscientiousness of engineering students. In this study, students' goals were categorized into either achievement-oriented goals or life-oriented goals for analysis. A cluster analysis was conducted using students' grit and life goals to analyze their psychological characteristics focusing on conscientiousness A sample of 123 engineering college students participated in this study. Results of correlation analysis showed positive correlations among grit, life goals, and conscientiousness. Results of cluster analysis suggested that student could be categorized into three different groups: Low-grit and high-goals (Group 1), high-grit and high-goals (Group 2), and low-grit and low-goals (Group 3). Among those three groups significant group differences were found in several sub-scales of conscientiousness. Group 1 and 3 showed significant differences in industriousness from Group 2. Group 1 showed significant differences in perfectionism from Group 2 and 3. Based on the findings of this study, theoretical and practical implications were discussed.