• Journal of the Korean Society for Railway
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• v.20 no.3
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• pp.413-422
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• 2017

In this study we investigate the importance of the subway station using network centrality measures. For centrality measures, we have used betweenness centrality, closeness centrality, and degree centrality. A new measure called weighted betweenness centrality is proposed, that combines both traditional betweenness centrality and passenger flow between stations. Through correlation analysis and power-law analysis of passenger flow on the Seoul metropolitan subway network, we have shown that weighted betweenness centrality is a meaningful and practical measure. We have also shown that passenger flow between any two stations follows a highly skewed power-law distribution.

• Journal of Internet Computing and Services
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• v.16 no.5
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• pp.39-47
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• 2015

The centrality is calculated to describe the importance of a node in a graph and ranking is given according to the centrality for each node. There are many centrality measures and we use degree centrality, closeness centrality, eigenvector centrality, and betweenness centrality. In this paper, we analyze the effect of an additional edge of a graph on centrality and ranking through experimental computations. It is found that the effect of an additional edge on centrality and ranking of the nodes in the graph is different according to the graph structure using PCA. The results can be used for define the graph characteristics.

• Journal of the Korean Society for information Management
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• v.30 no.4
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• pp.241-264
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• 2013

This study compared and analyzed weighted network centrality measures supported by Opsahl's tnet and Lee's WNET, which are free softwares for weighted network analysis. Three node centrality measures including weighted degree, weighted closeness, and weighted betweenness are supported by tnet, and four node centrality measures including nearest neighbor centrality, mean association, mean profile association, triangle betweenness centrality are supported by WNET. An experimental analysis carried out on artificial network data showed tnet's high sensitiveness on linear transformations of link weights, however, WNET's centrality measures were insensitive to linear transformations. Seven centrality measures from both tools, tnet and WNET, were calculated on six real network datasets. The results showed the characteristics of weighted network centrality measures of tnet and WNET, and the relationships between them were also discussed.

• Journal of the Korean Society for information Management
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• v.31 no.3
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• pp.153-179
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• 2014

This study explores the characteristics of centrality measures for analyzing researchers' impact and structural positions in research collaboration networks. We investigate four binary network centrality measures (degree centrality, closeness centrality, betweenness centrality, and PageRank), and seven existing weighted network centrality measures (triangle betweenness centrality, mean association, weighted PageRank, collaboration h-index, collaboration hs-index, complex degree centrality, and c-index) for research collaboration networks. And we propose SSR, which is a new weighted centrality measure for collaboration networks. Using research collaboration data from three different research domains including architecture, library and information science, and marketing, the above twelve centrality measures are calculated and compared each other. Results indicate that the weighted network centrality measures are needed to consider collaboration strength as well as collaboration range in research collaboration networks. We also recommend that when considering both collaboration strength and range, it is appropriate to apply triangle betweenness centrality and SSR to investigate global centrality and local centrality in collaboration networks.

• Journal of the Korean Society for Library and Information Science
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• v.40 no.3
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• pp.191-214
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• 2006

Recently, some bibliometric researchers tried to use the centrality analysis methods and the centrality measures which are standard tools in social network analysis. However the traditional centrality measures originated from social network analysis could not deal with weighted networks such as co-citation networks. In this study. new centrality measures for analyzing bibliometric networks with link weights are suggested and applied to three real network data, including an author co-citation network, a co-word network, and a website co-link network. The results of centrality analyses in these three cases can be regarded as Promising the usefulness of suggested centrality measures, especially in analyzing the Position and influence of each node in a bibliometric network.

• Korean Journal of Social Welfare Studies
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• v.41 no.4
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• pp.313-343
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• 2010

The aim of this study is to examine the factors influencing network centrality on women's welfare organizations, and to investigate how the level of network centrality influence the effectiveness of the organization. To achieve this goal, this study conducted a survey on women's welfare organizations in Seoul from March to June, 2009. Network analysis method was used to get each organization's network centrality value. Also, through the Structural Equation Modelling, organizational characteristics predicting network centrality and effect of network centrality on organizational effectiveness. The main results are as follows. First, the significant affecting factors were different between three types of centralities with regards to the type of organization, recognition of resource dependency, attitude of top manager, and established year. Second, the common factors affecting three network centralities were the number of informal ties, accepting feminism as the main organizational philosophy, and the number of qualified staffs. Third, only closeness centrality positively predicted the level of organizational effectiveness among three types of centralities. The faster the organization reaches to other organizations in a network, the organizational effectiveness becomes higher, which means high closeness centrality is more important factor than high degree centrality or high betweenness centrality to increase organizational effectiveness. This result shows social welfare organization should consider changing inter-organizational network strategy from quantity-focused to quality-focused.

• Journal of the Korean Society for information Management
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• v.32 no.2
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• pp.7-23
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• 2015

While there are several measures for node centralities, such as betweenness and degree, few centrality measures for local centralities in weighted networks have been suggested. This study developed a generalized centrality measure for calculating local centralities in weighted networks. Neighbor centrality, which was suggested in this study, is the generalization of the degree centrality for binary networks and the nearest neighbor centrality for weighted networks with the parameter ${\alpha}$. The characteristics of suggested measure and the proper value of parameter ${\alpha}$ are investigated with 6 real network datasets and the results are reported.

• Journal of Korea Port Economic Association
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• v.38 no.4
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• pp.25-43
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• 2022

Unlike the past, efforts must be made to interpret physical distribution from a network perspective as the service area expands spatially. In addition, logistics networks are undergoing rapid changes due to various changes in the environment. Therefore, the purpose of this study is to analyze the changes in the structure of maritime cargo and the centrality of ports using social network analysis. Using the trade data of domestic maritime at five-year intervals, we investigated changes in the network structure and identified the main factors that affect the centrality of domestic ports. Ports with the highest centrality, which is seen as a port that plays the role of an intermediary, emerged in the order of Busan and Ulsan. This study predicts patterns of domestic cargo trade over the next 20 years based on changes in port centrality and understanding of maritime cargo network, and can be used as reference materials for risk preparation.

• Journal of Korean Library and Information Science Society
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• v.44 no.3
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• pp.405-428
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• 2013

This study tried to explore the relation between research networks(coauthor network, author co-citation network, author bibliographic coupling network) and research performance of Records and Archives Management study in Korea. For the analysis, three basic types of network centrality and three indicators of research performance are used. The summary of this study is as follows: Firstly, there are relations between three centralities and three indicators of research performance in the coauthor network. Secondly, there are relations between betweenness centrality and research performance in the author co-citation/author bibliographic coupling networks. Thirdly, there are relations between three centralities in the each research network. Fourthly, there are not high relations between all centralities of the three research networks.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.05a
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• pp.314-315
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• 2018

본 연구는 사회연결망 분석을 활용하여 2012년부터 2016년까지 부산항을 기항하는 컨테이너 정기선 항로 패턴 분석을 통해 세계 주요항만과의 중심성을 파악하여 부산항과 연결되어 있는 항만 네트워크의 구조적인 특성을 파악하였다. 부산항 컨테이너 정기선 항로 네트워크상에 연결정도 중심성, 근접중심성, 매개중심성이 높은 항만은 싱가포르항으로 분석되었으며, 실제 연도별 부산항 주요 국가 항만별 처리 물동량 순위와 부산항 컨테이너 정기선 항로 네트워크 중심성 분석 결과 간 순위 비교는 서로 상이한 것으로 나타났다.