• Journal of Korea Multimedia Society
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• v.8 no.12
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• pp.1623-1630
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• 2005

Adaptive modulation and coding (AMC), which has a number of variation levels in accordance with the fading channel variation, is a promising technique for communication systems. In this paper, we present an AMC method using the cluster in OFDM system for bandwidth efficiency and performance improvement. The AMC schemes applied into each cluster or some clusters are determined by the minimum or the average SNR value among all the sub carriers within the corresponding cluster. It is important to find the optimal information on cluster because AMC performance can be varied according to the number and position of cluster. It is shown by computer simulation that the AMC method outperforms the fixed modulation in terms of bandwidth efficiency and its performance can be determined by the position and number of clusters.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.74.2-74.2
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• 2011

We probe the tidal perturbation parameter f of Virgo cluster galaxies. The goal is to measure the strength of tidal fields around individual galaxies to get better understanding gravitational processes that can affect galaxy evolution in the cluster environment. The f-value is defined as a logarithmic ratio between the net internal gravitational force within a galaxy and the external tidal force exerted by a neighboring galaxy. Hence, it provides one way to quantify the tidal field strength of galaxies, in particular, due to galaxy neighbors. In this study, we determine f-values of the VIVA galaxies, samples of the VLA Imaging study of Virgo galaxies in Atomic gas, using the Extended Virgo Cluster Catalog (EVCC) which is the most complete Virgo cluster catalog to date. With diagnostics based on the HI gas and R-band morphologies, we discuss the impact of the tidal fields on the evolution of the VIVA sample. Also, we compare the tidal field strength to the intra cluster medium (ICM) pressure for each sample galaxy to pin down environmental processes at work.

• Journal of the Korean Society of Costume
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• v.27
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• pp.87-101
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• 1996

The purpose of this study is to grasp the re-lationship between Sasang constitution of the disposition side and clothing value in grown-up women in order to apply Sasang consti-tution theory to the marketing strategy in clothing industry. The study is based on a questionnaie about Sasang constitution and clothing value. The questionnarie was answered by 519 women. The data ere collected from September 12 to September 30, 1994 and analyzed by cluster analysis correlation analysis ANOVA and fac-tor analysis using SAS. The Findings of this study are as follows: 1. The women were classfied in to 3 clusters by cluster analysis :Sp-Yaung-In type (30.8%) Tae-Em-In type (40.7%) So-em-in(28.5%). 2. Correlations between SO-Yaug In type and each of clothing values showed all signifi-cant and specially social value showed high corelation(0.57163) 3. In Tae-Em-In type all correlations showed significant and esocial value showed the highest correlation of all correlations. 4. In So-Em-In type there was no corre-lation inpolitical value and the order of cloth-ing values showing high correlation was theor-etical social economic and religious value. 5. The aesthetic valu among and consti-tution types showed the lowest correlation of all correlation. By means of the about study results we may know that all women belong to three types think social value of the more important value than any other in clothing value. This is because grown-up women in korea prefer yet clothing of the harmonic and similar type to this of individual type.

• Journal of Korea Port Economic Association
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• v.23 no.1
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• pp.41-59
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• 2007

Recently, the fresh logistics recognizes to be created the high value-added part for logistics companies. Because the fresh logistics, which provides the system of temperature control and sanitary management, is able to be created more better high value-added products than the existed logistics system. In this research, we suggest the fresh logistics cluster for the proposal of activation in the field of food industry, which apply good activity for fresh logistics, and show the present condition and matters domestic fresh logistics market. This study did analyze the status & volume of perishable cargo which come from the imported Chinese fresh products representatively, at Incheon port and assume to build the fresh logistics cluster complex at Songdo FEZ, which is available developing and located near by Incheon port. The actual intensive study should be progressed for Korean logistics companies in order to optimize to the suitable fresh logistics system, need to set up the policy and management of statistical data concerning fresh logistics system.

• Journal of Digital Contents Society
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• v.12 no.3
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• pp.339-345
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• 2011

The k-means has been one of the popular, simple and faster clustering algorithms, but the right value of k is unknown. The value of k (the number of clusters) is a very important element because the result of clustering is different depending on it. In this paper, we present a novel algorithm based on an external cluster relationship criterion which is an evaluation metric of clustering result to determine the number of clusters dynamically. Experimental results show that our algorithm is superior to other methods in terms of the accuracy of the number of clusters.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.295-296
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• 2009

본 논문은 기존 PSO의 문제점으로 지적되는 Local minimum에의 고착을 해결하여 평균적인 성능을 향상시킬 수 있는 방법을 제안한다. 이를 위해 기존에는 하나의 Best Value만을 향해서 이동하는 것에서 벗어나, 각 Particle들을 Cluster로 나누고 각각의 Best Value를 중심으로 이동하며, 각 Cluster Leader들은 다른 Cluster Leader와 통신하며 순위에 따라 이동한다. 제안 방법으로 수렴속도와 Local minimum 회피에 대해 실험을 통해 비교 분석한다. 실험 결과로부터 제안 방법이 Local minimum 회피에서 성능 향상이 있음을 고찰하였다.

• Atmosphere
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• v.16 no.4
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• pp.259-267
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• 2006

In the present study, the neural network (NN) model with cluster analysis method was developed to predict storm surge in the whole Korean coastal regions with special focuses on the regional extension. The model used in this study is NN model for each cluster (CL-NN) with the cluster analysis. In order to find the optimal clustering of the stations, agglomerative method among hierarchical clustering methods was used. Various stations were clustered each other according to the centroid-linkage criterion and the cluster analysis should stop when the distances between merged groups exceed any criterion. Finally the CL-NN can be constructed for predicting storm surge in the cluster regions. To validate model results, predicted sea level value from CL-NN model was compared with that of conventional harmonic analysis (HA) and of the NN model in each region. The forecast values from NN and CL-NN models show more accuracy with observed data than that of HA. Especially the statistics analysis such as RMSE and correlation coefficient shows little differences between CL-NN and NN model results. These results show that cluster analysis and CL-NN model can be applied in the regional storm surge prediction and developed forecast system.

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.2
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• pp.7-14
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• 2016

In this paper presents a low power algorithm using a feasible cluster generation method considered glitch. The proposed algorithm is a method for reducing power consumption of a given circuit. The algorithm consists of a feasible cluster generation process and glitches removal process. So that glitches are not generated for the node to which the switching operation occurs most frequently in order to reduce the power consumption is a method for generating a feasible cluster. A feasible cluster generation process consisted of a node value set, dividing the node, the node aligned with the feasible cluster generation. A feasible cluster generation procedure is produced from the highest number of nodes in the output. When exceeding the number of OR-terms of the inputs of the selected node CLB prevents the signal path is varied by the evenly divided. If there are nodes with the same number of outputs selected by the first highest number of nodes in the input produces a feasible cluster. Glitch removal process removes glitches through the path balancing in the same manner as [5]. Experimental results were compared with the proposed algorithm [5]. Number of blocks has been increased by 5%, the power consumption was reduced by 3%.

• World Technopolis Review
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• v.4 no.3
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• pp.144-156
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• 2015

Globalization and knowledge-based economy have increased the importance of local areas as the units of global competition. Therefore, the meaning of localities has been emphasized as the core value of economic activities. In this context, innovation cluster has been recognised and emphasized as effective policy measure for innovation. Therefore, most countries have been trying to develop innovation clusters with their expectation for a rapid growth of economy. Nevertheless, there have been minimal empirical researches on innovation cluster. Therefore, for suggesting implications that activation factors of innovation cluster are to have an effect on tenant's business activities, this study conducted a literature review for the theories of regional innovation system(RIS) and innovation cluster. As a result, the activation factors of innovation cluster were classified into institutional, physicals, and social factor. The case of Gyeonggi province's innovation cluster policy was examined for an empirical analysis. Data were analyzed using ordered logistic regression. The results were as follows:First, Institutional and Infra factors had a positive influence on firms' business activities in every empirical test, so they were the most important activation factors of innovation cluster. Second, regarding the interactive effects of financial support, the interactive effects between financial support and Infra factor had a positive influence on the firms' business activities, according to the result of the empirical test.

• The Journal of the Korea Contents Association
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• v.9 no.10
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• pp.398-406
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• 2009

This study intends to provide support for tourism industry to establish marketing strategies for selling the travel products on which it should focus on more by examining the difference on selection of travel product attributes by tourism action. This research utilized cluster analysis and ANOVA. The cluster analysis identified four cluster: logical tourism, weak conspicious tourism, value tourism, conspicuous and value tourism. ANOVA analysis showed that four cluster were different in terms of tourism action such as transportation accommodation facilities, tourist attractions, shopping and meals except for travel service, entertainment.