• Journal of Digital Convergence
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• v.11 no.12
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• pp.453-458
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• 2013

In a wireless LAN environment, security is the most important. Security of 802.11 standard has many vulnerabilities of the network attack. IEEE has created mechanisms to security for this vulnerability. But the vulnerabilities is characteristic of broadcast in the air in wireless LAN, it is more disclosure then other network environments. In a wireless LAN environment, it can be accessed to the wireless LAN after authentication. Authentication process is one of most important because of the first security step. However, in the authentication process is not mentioned in the method of reducing the disclosure maximum fundamental. Therefore, in this research, the vulnerability of 802.11 are presented and how to do de-authentication in 802.11.

• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.4
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• pp.111-122
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• 1999

In this paper, we consider a queueing network model. where the population constraint within each subnetwork is controlled by a semaphore queue. The total number of customers that may be present in the subnetwork can not exceed a given value. Each node has a constant service time and the arrival process to the queueing network is an arbitrary distribution. A major characteristics of this model is that the lower layer flow is halted by the state of higher layer. We present some properties that the inter-change of nodes does not make any difference to customer's waiting time in the queueing network under a certain condition. The queueing network can be transformed into a simplified queueing network. A dramatic simplification of the queueing network is shown. It is interesting to see how the simplification developed for sliding window flow control, can be applied to multi-layered queueing network.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.62-69
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• 2012

This thesis proposes a new social network simulator, which can be used for the social network analysis (SNA). It is composed of three modules; initialization, network evolution, and output generation. For the network evolution module, we suggest a modified JGN (MJGN) based on JGN, the network evolution model developed by Jin, Girvan, and Newman. Arena, one of the most popular simulation tools, was used to model the agent based social network simulator. Lastly, some test results were presented to show the value of the proposed simulator when one performs SNA at the longitudinal point of view.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.6
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• pp.1189-1194
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• 2005

An Ad-hoc network which do not use wired and base station system is composed the group of mobile and wireless nodes. That is various type of restriction. The biggest restriction is depend on the confined energy of battery. The network is devide more than two, if one of nodes consumed all energy that node can no longer participate to network. In recent years, the many number of studies research not only energy saving but also the networks lifetime extension which is to solve this problem. In this paper, we examine a AODV routing protocol which is modified to improve networks lifetime in mobile ad-hoc network. The one of improvement for AODV protocol is maximize the networks lifetime as apply Energy Mean Value algorithm which considerate node energy. We show the effectiveness for modified AODV(New-AODV) compared with AODV using NS-2(Network Simulator 2) the various performance metrics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.595-602
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• 2020

This study analyzes the plan to increase the social value of the KRC (Korea Rural Community Corporation). For this aim, this study examines the current status of participation in the KRC business and the social value, targeting the farmers among the external stakeholders and derived the main characteristics and important projects of the KRC using network analysis. As a result of network analysis, the rural water management business was found to be the most important business in most regions (Rural Water Development Business 0.805, Agricultural and Fishery Production Base Maintenance Business 0.758, Farmland Banking Business 0.762, Regional Development Business 0.643). On the other hand, in the case of Jeju, the agricultural production base improvement business and the regional development project were found to be the most important projects of KRC due to the unique characteristics of the region. The results of this kind of analysis differ in the importance between KRC business by region, and it is necessary to carefully review the local conditions in order to enhance social value through KRC business in the future. However, since the value of degree centrality between each business is different for each region, efforts to increase the value of KRC's social value, while accounting for local conditions, are needed.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.11
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• pp.159-166
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• 1996

In this paper, the method for improving the speed of convergence and learning rate of back propagation algorithms is proposed which update the learning rate parameter and momentum term for each weight by generated error, changely the output layer of neural network generates a high value in the case that output value is far from the desired values, and genrates a low value in the opposite case this method decreases the iteration number and is able to learning effectively. The effectiveness of proposed method is verified through the simulation of X-OR and 3-parity problem.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06a
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• pp.13-16
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• 2011

최근 들어 네트워크1로 연결된 체계들을 효율적으로 운영하여 최대의 효과를 달성하기 많은 연구들이 수행되고 있다. 하지만 지휘통제체계 네트워크 구조 분석에 관한 연구는 상대적으로 미흡한 실정이다. 따라서 본 연구에서는 지휘통제체계 중 육군의 SPIDER체계를 대상으로 소설 네트워크 분석 (Social Network analysis)기법을 이용하여 중앙성분석과 시각화(Visualization)를 통해 핵심노드를 식별하는 arms value 알고리즘을 제안하고 분석 결과를 기반으로 TICN체계 전력화시 기초 연구자료로 활용하고자 한다.

• Journal of Information Technology Services
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• v.11 no.3
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• pp.287-304
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• 2012

Cloud computing, which means a new way of deploying information technology(IT) in organizations as a service and charging per use, has a deep impact on organizations' IT accessibility, agility and efficiency of its usage. More than that, the emergence of cloud computing surpasses a mere technological innovation, making business model innovation possible. We call this innovation realized by could computing a cloud business model. This study develops a comprehensive framework of business model, first, and then defines and analyzes the cloud business model through this framework. This study also examines the case of M-Pesa mobile payment as a cloud business model in which a new value creation and profit realization schemes have been realized and industry value network has changed. Finally, this study discusses the business implications from this new business model.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.838-840
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• 2002

Presently, Analytic Network Process which evaluates man's intention and offers decision-making support is capturing the spotlight. It originates in the ability of Analytic Network Process to treat various decision-making support system. However, no detailed reference is available when dealing with the group case. This paper examines the technique, which can also cope with the group decision-making support system, and describes the validity of the technique. A characteristic feature of the proposed technique is that it can detect a group's intention in a given section, and it decomposes the sectional supermatrix into a small supermatrix and a large one. A general supermatrix treats the convergence value by taking the limiting process method of the power of an evaluation value. On the other hand, when a supermatrix has nonnegative value, it can easily be solved by the eigenvector method. The decomposition of the supermatrix has been considered in this work.

• The Journal of Society for e-Business Studies
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• v.3 no.1
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• pp.155-173
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• 1998

In this paper we present the development of internet banking and its impact on financial market. The internet banking has been introduced since 1990s, from which customers could obtain most financial services over internet, and will replace with the traditional banks. According to a survey, most of bankers agree that internet will play an important role in banking industry. The internet banking has an enormous impact on the transfer system and banking industry. The transfer system is divided into two-large-value transfer system and small-value transfer system, depending on the size of its transfer amount. The internet banking will enhance the transfer system, especially small-value transfer system. It will reduce the time lag between transaction of service and its payment. However, a congestion or a blockage in a part of network might stop the financial service all over the network, which is called "computer risk". As internet banking develops, banks have incentives to reduce their branches and have to compete with information-business companies which can offer financial EDI.