• The Bulletin of The Korean Astronomical Society
• /
• v.38 no.2
• /
• pp.48.1-48.1
• /
• 2013

We present galaxy luminosity functions (LFs) of subgroups in the Ursa Major cluster. The membership of galaxies is determined by radial velocities which are compiled from the SDSS and NED. We found that the faint end slope (${\alpha}$) of the LF of all sample galaxies in Ursa Major is ${\alpha}=-1.13$. This is consistent with previous result, but shallower than that of the Virgo cluster. Interestingly, the subgroups in Ursa Major show different slopes in their LFs. The NGC 3992 and NGC 4111, the massive subgroups in the Ursa Major cluster, exhibit steep slopes of their LFs comparable to that of the Virgo cluster. On the other hand, less massive group (NGC 3877) shows a very shallow slope of -0.84. Based on the results, we discuss the evolution of galaxies and the assembly history of the Ursa Major cluster.

• Korean Journal of Childcare and Education
• /
• v.16 no.4
• /
• pp.31-49
• /
• 2020

Objective: The purpose of this study was to examine cluster types according to the playfulness factors of young children and to predict the character strengths of young children which have an influence on the types of children's playfulness. Methods: Playfulness and character strength tests were administered to 237 young children. The playfulness groups were classified by cluster analysis and the logistic regression analysis. It was used to find the character strengths of young children that have a effect on the types of children's playfulness. Results: First, the children's playfulness groups were divided into a high playfulness group and a low playfulness group. Second, there was a significant difference in all character strengths according to the children's playfulness cluster, and the high playfulness group was statistically significantly high in all character strengths. Third, the children's character strengths influencing the high playfulness group were vitality and positivity, self-regulation, self-esteem, and sensibility. Conclusion/Implications: Based on these results, the necessity of supporting these character strengths was discussed in order to improve the playfulness of children in the education field.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.50 no.4
• /
• pp.455-466
• /
• 2014

Seasonal variations in species composition of catches were explored using seasonal samples caught by shrimp beam trawl in the Geum river estuary in 2011. During the study period, total catches were collected 91 species as fish 47 species, crustacean 28 species, mollusca 4 species, gastropoda 5 species, shellfish 3 species and others 4 species. The dominant species were Exopalaemon carinicauda, Eriocheir leptognathus, Palaemon gravieri, Mugil cephalus, Acanthogobius hasta, Cynoglossus joyneri, Pennahia argentata and Coilia nasus. The amount of species in spring and summer was higher than in autumn. The diversity index (H') was 0.43~0.96, evenness index (EI) was 0.14~0.25, and richness index (RI) was 1.54~4.25. Using cluster analysis 91 species were divided into 4 groups. Group I appeared mainly in spring and summer. Group II appeared only in summer. Group III appeared in winter and spring, and Group IV in spring and autumn.

• Journal of the Korea Convergence Society
• /
• v.9 no.5
• /
• pp.179-189
• /
• 2018

Currently, research on smart factories is steadily being carried out in terms of implementation strategies and considerations in construction. Various studies have not been conducted on companies that introduced smart factories. This study conducted a questionnaire survey for SMEs applying the basic stage of smart factory. And the cluster analysis was conducted to examine the characteristics of the company. In addition, we conducted Decision Tree and Naive Bay to examine how the characteristics of a company are derived and compare the results. As a result of the cluster analysis, it was confirmed that the group was divided into the high satisfaction group and the low satisfaction group. The decision tree and the Naive Bay analysis showed that the higher satisfaction group has high productivity.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.18 no.3
• /
• pp.99-111
• /
• 2016

In order to use cosmetics brands SNS effectively and establish strategy, the purpose of this study is to provide consumer date. According to cosmetics consumption value groups, this study examined each cosmetics consumption value group's level of concern of three cosmetics brands SNS features, informativity, enjoyment and interactivity. For the data, questionnaire was collected by 198 women, and the data were measured by ANOVA, factor analysis, cluster analysis and Ducan test. According to cluster analysis cosmetics consumption value groups were divided into four groups, unconcern group, hedonic value pursuit group, function of brand value pursuit group, high concern group. The results of the study are as follows: First, high concern group thought highly of all cosmetics brands SNS features, including informativity, enjoyment and interactivity. In addition all consumer groups were concerned informativity rather then enjoyment and interactivity. Second, comparing with high concern group, other groups which include unconcern group, hedonic value pursuit group and function of brand value pursuit group were not concerned about cosmetics brands SNS features' enjoyment and interactivity. Except informativity, hedonic value pursuit group and unconcern group were more concerned interactivity than enjoyment. While, high concern group and function of brand value pursuit group were more concerned enjoyment than interactivity.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.28 no.7
• /
• pp.1019-1028
• /
• 2004

The purpose of this study was to compare the body measurements of cyclists and non-cyclists and to classify cyclists＇ body types to offer basic information for the bicycle apparel manufacturer in Korea. The anthropometric data was collected including both direct and indirect measurements of 81 cyclists (40 female, 41 male) aged from 19 to 24. Anthropometric measurements were analyzed using percentiles, T-test, factor and cluster analysis. The results were as follows; Comparison of anthropomeoic data between cyclist and non-cyclist was to clarify that cyclists have bigger size than non-cyclists; especially the thigh circumference shows big differences. As the result of factor analysis, 5 factors, which explain 74% of variance, were extracted from all items for male and female cyclists. The results of cluster analysis classified body types into 3 groups. Cluster 1 among three female cyclist groups has biggest torso and had an erect back. Cluster 2 has small size among three female group and drooping shoulders. Cluster 3 has the bended forward shoulders and shows the protrusion back. In case of male cyclists, cluster 1 has thin body type owing to big height measurements and small girth measurements. Cluster 2 among three male groups has the biggest torso and thigh circumference. Cluster 3 has big forward angle of shoulders and shows the protrusion of the back as female cyclist.

• The Research Journal of the Costume Culture
• /
• v.9 no.2
• /
• pp.319-332
• /
• 2001

This study attempts to measure body sizes and somatotypes of 844 female middle and high students girls in their growth period and to investigate characteristics of each of the measured somatotypes. The data used for this study were 50 items of body sizes obtained from anthropometric measurements. The purposes of the study are as follows: 1. to analyze physical characteristics according to age. 2. to extract factors of somatotypes using factor analyses. 3. to classify somatotypes according to physical characteristics using cluster analyses. The study results were as follows: 1. TH anthropometric measurements indicated that three existed collective patterns of somatotypes across Group I(12∼13 years old), Group II(14∼15 years old), and Group III(16∼18 years old). 2. Through factor analyses, 6 factors were yielded from each age group. The cumulative proportions of these factors were 77% for Group I, 75% for Group II, and 72% for Group III. Factor I indicates a horizontal size factor and Factor 2 indicates a vertical size factor. 3. Group I and Group II ere classified into 5 types and Group III was classified as 3 types. In Group I, middle height and a little slim types were most prevalent(28%). In Group II, low height and very slim types were most prevalent(28.9%). Finally, In Group III, low height and slim types were most prevalent(4.6%)

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.49 no.4
• /
• pp.295-299
• /
• 2004

The prices of domestic green tea products are relatively expensive and price differences within products of the same levels of quality are various. Also, there is no basic criteria on evaluation of green tea quality. To group 43 commercial green tea products into several parts by the principal component and cluster analyses, this work was done by use of 8 chemical constituents which were analyzed by NIR system. The principal component and cluster analyses revealed 8 groups. The first group included 16 products that had lower free amino acid and theanine contents. The second group included 5 products having higher free amino acid and theanine contents, but lower ash contents. The third group included 13 products showing medium values of 8 constituents. The IV group included 4 products having higher contents of moisture, free amino acids, and theanine. The V group included 1 product showing higher moisture but lower catechins contents. The VI group included 2 products that had higher moisture and catechins contents, but lower free amino acid and theanine contents. The VII group had higher moisture and catechins contents. The VIII group had higher ash and vitamin C contents. The free amino acid contents which were the most important in flavor evaluation of green tea quality did highly positively correlate with the contents of total nitrogen $(0.956^{**}),\;theanine\;(0.981^{**}),\;and\;caffeine\;(0.793^{**})$, but negatively with the contents of ash $(-0.884^{**})$. The catechins used as for functional ingredients did correlate with contents of caffeine(+) and vitamin C(-), respectively.

• The Research Journal of the Costume Culture
• /
• v.7 no.1
• /
• pp.38-51
• /
• 1999

For a ideal construction of shoes, the exact analysis for shape and size of foot is necessary. This study was performed to classify and analyze the foot types of young males and females. For this, methods of cluster analysis, correspondence analysis and value of proportion were used. The subjects were 414 college students and 36 items, weight(1 item), height(8 items), length(6 items), breadth(6 items), girth(7 items), depth(3 items), slope(5 items) on foot were measured. The fundamental results of the study were as follow ; Difference in foot shape between men\`s and women\`s feet was not found below ankle girth. Based on cluster analysis the shapes of foot were classified into five groups, small but relatively slim group, small but relatively barrel group, middle group, large but relatively slim group and large but relatively barrel group. The types of foot had the distinguished dominant characteristics according to sex, weight and height. The results of this study show that there must be the suitable design of shoes for each foot type.

• Convergence Security Journal
• /
• v.7 no.2
• /
• pp.107-118
• /
• 2007

Distributed wireless sensor network in various environment have characteristic that is surveillance of environment-element and offering usefully military information but there is shortcoming that have some secure risks. Therefore secure service must be required for this sensor network safety. More safe and effective techniques of node administration are required for safe communication between each node. This paper proposes effective cluster-header and clustering techniques in suitable administration techniques of group-key on sensor network. In this paper, first each node transmit residual electric power and authentication message to BS (Base-Station). BS reflects "Validity Authentication Rate" and residual electric power. And it selects node that is more than these regularity values by cluster header. After BS broadcasts information about cluster header in safety and it transmits making a list of information about cluster member node to cluster header. Also, Every rounds it reflects and accumulates "Validity Authentication Rate" of former round. Finally, BS can select more secure cluster header.