• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.33.3-34
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• 2015

We present the spectroscopic study of the globular clusters (GCs) in the massive elliptical galaxy M86 in the Virgo galaxy cluster. Using the spectra obtained from the Multi-Object Spectroscopy (MOS) mode of Faint Object Camera and Spectrograph (FOCAS) on the Subaru Telescope, we measure the radial velocities for 56 GCs in M86. The mean velocity of the GCs is derived to be $<v_p>=-335{\pm}41km/s$, which is different from the velocity of the M86 nucleus ($<v_{gal}>=-224{\pm}5km/s$) within ${\sim}2.5{\sigma}$. The mean velocity ($<v_p>=-342{\pm}60km/s$) of 33 blue GCs in M86 is similar to that ($<v_p>=-314{\pm}71km/s$) of 23 red GCs. We also derive the mean velocities of the GC systems in other 16 nearby early-type galaxies (ETGs) from the radial velocity data in the literature. The mean value of the differences between the mean velocity of the GC systems in each galaxy and the nucleus velocity of their host galaxies, is almost zero except the M86 GC system. But the scatter of the differences in the blue GC system is larger than that in the red GC system. We will discuss these results in the context of GC formation in ETGs.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.3
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• pp.345-352
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• 2000

The purpose of this study was to classify lower body types of elementary school girls. The subjects for anthropometric study were 368 girls aged from 10 to 11. Factor analysis, cluster analysis, discriminant analysis, and analysis of variance were performed for statistical analysis of the data. Four lower body construction factors were extracted by the factor analysis of antropometric measurements. The factors extracted were lower body fatness factor, lower body height factor, lower body length from the waist to the crotch factor, and lower body configuration factor. On the basis of the cluster analysis, three different lower body types were categorized. Type 1 was short and small sized type and 42.4% of subjects belonged under this type. Type 2 was tall and fat type and 22.3% of subjects belonged under this type. Type 3 was the most similar to the average type having the largest waist-hip drop value and 35.3% of subjects belonged under this type. Discriminant analysis showed 7 discriminant factors that can classify the children's lower body type were Rohrer's index, height, fibulae length, waist girth, ilio cristale girth, trochanter girth, and weight.

• Korean Journal of Human Ecology
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• v.22 no.6
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• pp.659-672
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• 2013

Nowadays, sports and outdoor market has been popular and expanding since the implementation of the five-day workweek and change of lifestyle. Outdoor clothing considered exclusive property of the middle-aged individuals in the past. Recently there is a drift towards having outdoor looking at the age of 10-20. The purpose of this study was to analyze the features of purchasing behaviors and demographics by each groups targeting middle school and high school students. The study was conducted with questionnaires towards people who live in the city of Busan and who have experiences of buying outdoor clothing. Data analysis was conducted via SPSS 18.0 with factor analysis, cluster analysis, ANOVA, cross tabulation, frequency analysis and Duncan's multiple range test. The results showed that there were five factors sought for outdoor wear benefits: Individuality/Fashion, Brand, Attractive appearance, Economic value, Comfort/Functional. Cluster analysis showed that there were four groups of outdoor wear benefits sought. Overall, the four groups were different in regard to purchasing behaviors and demographics. Based upon the results mentioned above, this study summarizes the key features of each group and can provide applicable suggestion for conducting strategic marketing activities.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.574-575
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• 2018

The generation of redundant data according to the spatial-temporal correlation in a wireless sensor network that reduces the network lifetime by consuming unnecessary energy. In this paper, data collection experiment through the particulate matter sensor is carried out to confirm the spatial-temporal data redundancy and we propose permitted limit setting method for data transmission to solve this problem. In the proposed method, the data transmission permitted limit is set by using the integrated average value in the cluster. The set permitted limit reduces the redundant data of the member node and it is shows that redundant data reduction is possible even in a variable environment of collected data by resetting the permitted limit in the cluster head.

• Journal of Environmental Science International
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• v.16 no.1
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• pp.103-119
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• 2007

We have analysed the observed surface and vertical meteorological data to get atmospheric information over the Busan metropolitan area. For this, we have selected 10 days in all season such as spring, summer I(Jangma season), summer II(hot season), autumn and winter. The result which have performed cluster analysis using atmospheric data represented that these days are included to most frequently appeared synoptic cluster. We have simulated wind field around Busan metropolitan area which is assigned as $1km^2$ using RAMS. The calculated air temperature and the wind speed was similar to the observed the that, and the trends of daily variation showed good agreement. RMSE and IOA also showed reliable value. These results indicated the RAMS is able to simulate and predict detailed atmospheric phenomenon.

• The Journal of Information Systems
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• v.26 no.4
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• pp.227-246
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• 2017

Purpose: As the importance of software has been emphasized recently, the size of the software market is continuously expanding. The development of the software market is being adversely affected by software piracy. In this study, we try to classify countries around the world based on the macro environmental factors, which influence software piracy. We also try to identify the differences in software piracy for each classified type. Design/methodology/approach: The data-driven approach is used in this study. From the BSA, the World Bank, and the OECD, we collect data from 1990 to 2015 for 127 environmental variables of 225 countries. Cronbach's ${\alpha}$ analysis, item-to-total correlation analysis, and exploratory factor analysis derive 15 constructs from the data. We apply two-step approach to cluster analysis. The number of clusters is determined to be 5 by hierarchical cluster analysis at the first step, and the countries are classified by the K-means clustering at the second step. We conduct ANOVA and MANOVA in order to verify the differences of the environmental factors and software piracy among derived clusters. Findings: The five clusters are identified as underdeveloped countries, developing countries, developed countries, world powers, and developing country with large market. There are statistically significant differences in the environmental factors among the clusters. In addition, there are statistically significant differences in software piracy rate, pirated value, and legal software sales among the clusters.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.6
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• pp.111-116
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• 2009

LEACH is a important hierarchical protocol in wireless sensor network. In LEACH, the head is randomly selected for balanced energy consume. In LEACH-C, the node that has more energy than the average value is selected for the network life cycle. However, the round continues, the improved protocol is needed because the energy and network are changed. In this paper, LEACH, LEACH-C is not considered the energy consumed in the round because of wasted energy and reduce the time for presenting a new round time was set. And proposed the new algorithm using the energy threshold for the cluster head selection and the round time. In simulation, we show the improved performance compared to existing protocols.

• Clean Technology
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• v.22 no.1
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• pp.62-72
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• 2016

These days, it seems to be a core time to build proactive prevention systems for small and medium sized enterprises due to the reinforced safety in the production process and the strong environmental regulations (ES) both at home and abroad. On the other hand, a network of experts that combines the industrial environment and production safety as well as even the knowledge services companies are not quite enough to prepare to support them. In this study, through a survey of experts the current statue of the convergence of industrial environment and production safety were reviewed, and the structure of knowledge ES cluster was proposed to overcome this current state. Detailed strategies such as the development and distribution of ES convergence methodology, ES efficiency analysis and an ES roundtable.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.2960-2976
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• 2018

The limited storage and computing capacity hinder the development of cognitive radio ad hoc networks (CRAHNs). To solve the problem, a new paradigm of cloud-based CRAHN has been proposed, in which a CRAHN will make use of the computation and storage resources of the cloud. This paper envisions an integrated CRAHN-cloud network architecture. In this architecture, some cognitive radio users (CUs) who satisfy the required metrics could perform as mobile gateway candidates to connect other ordinary CUs with the cloud. These mobile gateway candidates are dynamically clustered according to different related metrics. Cluster head and time-to-live value are determined in each cluster. In this paper, the gateway advertisement and discovery issues are first addressed to propose a hybrid gateway discovery mechanism. After that, a QoS-based gateway selection algorithm is proposed for each CU to select the optimal gateway. Simulations are carried out to evaluate the performance of the overall scheme, which incorporates the proposed clustering and gateway selection algorithms. The results show that the proposed scheme can achieve about 11% higher average throughput, 10% lower end-to-end delay, and 8% lower packet drop fractions compared with the existing scheme.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.3
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• pp.35-51
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• 2014

A phytosociological vegetation survey was conducted in July to September 2011 in order to examine the vegetation community structure in Mt. Ohseo area. It was aimed to provide basic data for the effective vegetation conservation by analyzing the importance, species diversity and community similarity of the forest community in Mt. Ohseo for each layer, followed by the classification of the actual forest vegetation. According to the cluster analysis, the community type of Mt. Ohseo was classified into a total of 4 vegetation communities: Pinus densiflora community, Cornus controversa-Quercus serrata community, Miscanthus sinensis community, and Quercus mongolica community; the vegetation type 4 showed the lowest species diversity index of 0.5236, and vegetation type-2 showed the highest species diversity index of 0.6606. The community similarity between Quercus mongolica community and Pinus densiflora community showed the highest 0.679, and the community similarity between Quercus serrata community and Pinus densiflora community and between Quercus serrata community and Quercus mongolica community showed the levels of 0.5, respectively.