• Communications for Statistical Applications and Methods
• /
• v.16 no.6
• /
• pp.937-943
• /
• 2009

A network with variable link capacities is considered to be in a functioning state if it can transmit a maximum flow which is greater than or equal to a specified amount of flow. The links are independent and either function or fail with known probability. No flow can be transmitted through a failed link. In this paper, we consider the measures of importance of a link in such networks. We define the structural importance and reliability importance, with respect to capacity, of a link when the required amount of flow is given. We also present the performance importance with respect to capacity. Numerical examples are presented as well for illustrative purpose.

• Annual Conference of KIPS
• /
• 2015.04a
• /
• pp.668-671
• /
• 2015

이 논문은 대한민국의 주식시장에 상장한 기업의 지배구조 분석을 위해 대주주가 어떠한 형태로 주식을 보유하고 있는지에 대한 네트워크 분석이다. 분석대상은 주식시장에 상장한 기업과 그 기업의 주식의 대주주 데이터를 모두 수집하였다. 이를 기업과 대주주 행위자 간에 주식을 보유하고 있는 네트워크를 분석하여 그 보유형태의 의미를 파악하였다. 분석결과 네트워크 형태는 크게 '전체분석, 산업분석, 군집분석, 상장기업분석, 대주주분석, 계열사 분석' 여섯 가지이다. 네트워크 분석결과 주식시장은 전형적인 척도 없는 네트워크 형태를 나타내었으며 반면 그룹간의 계열사 네트워크는 전형적인 계층구조로써 좁은 세상 네트워크의 사례를 나타내었다. 따라서 투자 성향이 갖거나 대주주 간의 이해관계가 있거나 투자상품들이 포트폴리오로 조합원 경우 대주주 간의 네트워크가 밀집된 것을 확인할 수 있었다.

• Annual Conference of KIPS
• /
• 2006.05a
• /
• pp.357-360
• /
• 2006

본 논문에서는 베이지안 네트워크 학습 방법을 이용한 비교적 적은 양의 샘플 데이터에서 현실적인 네트워크 모델 추론을 위한 효율적인 스코어링 척도를 찾는 것을 목표로 하였다. UPSM, CUPSM, DPSM, BDe(Bayesian Dirichlet) 등을 각각 적용시켜본 결과를 통해 어떤 방법이 가장 적은 샘플의 데이터, 특히 생물학적 데이터에적합한지 알아보았다.

• The Journal of the Korea Contents Association
• /
• v.22 no.6
• /
• pp.24-34
• /
• 2022

Viewing religion as contents, we analyzed the network structure by creating networks on 13 world religions. The whole network was constructed by combining 13 religions, and it showed the characteristics of a scale-free network as a general social network. The world religion network had a very small value of clustering coefficient, unlike the general social network. This seems to be the result of the diversity of terms that describe religion. The core network was constructed by applying K-core algorithm used to create the core network to the whole network. When k-3 was applied, it was too complicated but when k-4 was applied, it was too simple to obtain meaningful results. It indicates that it difficult to apply the K-core algorithm to a network containing a low clustering coefficient. Therefore, core networks were constructed according to the number of key words centered on the hub node to analyze the characteristics of world religions. In addition, meaningful information was derived by constructing the world's five major religious networks and East Asian religious networks. In this study, various information was obtained by analyzing world religions as contents. It was also presented a method of creating and analyzing a core network based on key words for networks with a low clustering coefficient.

• Journal of KIISE:Computer Systems and Theory
• /
• v.34 no.5_6
• /
• pp.202-213
• /
• 2007

A network is an important model widely used in natural and social science as well as engineering. To analyze these networks easily it is necessary that we should layout the features of networks visually. These Graph-Layout researches have been performed recently according to the development of the computer technology. Among them, the Scale-free Network that stands out in these days is widely used in analyzing and understanding the complicated situations in various fields. The Scale-free Network is featured in two points. The first, the number of link(Degree) shows the Power-function distribution. The second, the network has the hub that has multiple links. Consequently, it is important for us to represent the hub visually in Scale-free Network but the existing Graph-layout algorithms only represent clusters for the present. Therefor in this thesis we suggest Graph-layout algorithm that effectively presents the Scale-free network. The Hubity(hub+ity) repulsive force between hubs in suggested algorithm in this thesis is in inverse proportion to the distance, and if the degree of hubs increases in a times the Hubity repulsive force between hubs is ${\alpha}^{\gamma}$ times (${\gamma}$??is a connection line index). Also, if the algorithm has the counter that controls the force in proportion to the total node number and the total link number, The Hubity repulsive force is independent of the scale of a network. The proposed algorithm is compared with Graph-layout algorithm through an experiment. The experimental process is as follows: First of all, make out the hub that exists in the network or not. Check out the connection line index to recognize the existence of hub, and then if the value of connection line index is between 2 and 3, then conclude the Scale-free network that has a hub. And then use the suggested algorithm. In result, We validated that the proposed Graph-layout algorithm showed the Scale-free network more effectively than the existing cluster-centered algorithms[Noack, etc.].

• The Journal of the Korea Contents Association
• /
• v.12 no.4
• /
• pp.476-484
• /
• 2012

Family member network of kings in Chosun dynasty shows scale free network properties as if most social networks do. One of distinct topological properties of the network is relatively high diameter that reflects dataset composed of the one generation continuously falling to next one. When k-core algorithm as a useful tool for obtaining a core network from the complex family member network was employed, it is possible to obtain hidden and valuable information from a complex network. Unfortunately, it is found that k-core algorithm is not useful tool for applying narrow and deep structural network. The family member network is composed of kings, queens, princes, and princesses. It is possible to separate sub-family members and to construct sub-family member networks such as queen-centered, prince-centered, and princess-centered networks. Sub-family member networks provide an useful and hidden information. These results provide new insight that is analyzed by network-based approaches for the family member of the kings in the Chosun dynasty.

• The Journal of the Korea Contents Association
• /
• v.15 no.5
• /
• pp.582-591
• /
• 2015

Late-Koryeo people networks were constructed from four different history books that were written by various historic aspects in the period from king Kongmin to the final king of the Koryeo, Kongyang. All networks constructed in this study show scale free network properties as if most social networks do. Tajo-sillok preface is one of subjectively written history book that described personal history of the Lee Seong-gye and his ancestors. It is confirmed that the book is one of the most biased-written history books through network study. Jeong Do-jeon known as a Chosun dynasty projector is not greatly contributed for founding of a Chosun dynasty in network study and various historical documents as well. In this network study, we provide objective historical information in the historical situations of the late-Koryeo and during establishment procedure of Chosun dynasty. Hub nodes in network is denoted highly linked nodes, called degree. Stress centrality is a unit to measure positional importancy in the network. If we employ two factors, degree and stress centrality to determine hub node, it represents high connectivity and importancy as well. As comparing values of the degree and stress centrality, we elucidate more objective historical facts from late-Koryeo situations in this study. If we further develop and employ a new algorithm that is considered both degree and stress centrality, it is a very useful tool for determining hub node.

• Korean Journal of Construction Engineering and Management
• /
• v.10 no.4
• /
• pp.151-164
• /
• 2009

Strategic alliances developed as formalized inter-organizational relationships are core vehicles to share information, resources and knowledge. The structural characteristics of strategic network constructed by strategic alliances have been important agenda in strategic management discipline. This paper has two folds in analysing the strategic network formulated by project level alliances in Korean construction industry. First, we investigate the strategic network using the tools and methods of social network analysis, such as centrality, cohesion, structural equivalence, and power law. Second, the performance of firms within networks are analysed longitudinally with panel data analysis. We have found that the strategic networks in this industry has scale-free characteristics, where the degree distribution fits the power law, and the vertically equivalent structure is clear. We also present that the performance of firms are continuously affected by the degree centrality of firms in this network for the last 10 years.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.607-608
• /
• 2013

무선 애드훅 네트워크에서는 무선링크의 성능을 표현하는 다양한 품질 척도가 있다. 그것은 노드가 움직임이 없는 상태에서 주변 무선 상태를 반영한다. 하지만 해상 환경에서는 선박의 이동성 뿐만 아니라 바람과 파고에 의해 선박이 움직이는 특성이 있다. 따라서 선박에 위치한 안테나의 흔들림을 유발하여 신호의 수신을 불안정하게 만든다. 본 논문은 선체운동에 따른 무선 링크 성능을 분석한다. 이를 위해 자이로 센서를 이용하여 서로 다른 해상 환경에서 선체운동을 측정 및 분석하고, 하드웨어 및 소프트웨어에 의한 무선 링크 안정화 방안을 제시한다.

• Annual Conference of KIPS
• /
• 2009.11a
• /
• pp.449-450
• /
• 2009

사용자의 인터넷 소비성향을 파악하고 그에 적응적인 인프라 리소스를 제공하는 일은 네트워크 설계/관리자나 인터넷 서비스 공급자(ISP)들에게는 주요 관심사이다. 이러한 분석은 한정된 네트워크 자원을 보다 적절한 지점에 효율적인 방식으로 투자하도록 도와준다. 본 논문은 각종 인터넷 서비스를 활용하는 사용자들의 서비스(각종 인터넷 어플리케이션) 소비성향을 네트워크 트래픽 관찰만으로 파악할 수 있는 성향분류 척도를 제안한다. 아울러 베이지안 분류기를 사용하여 제안 척도를 활용한 사용자 성향 분류 방법을 함께 제시한다.