• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.633-636
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• 2011

The paper deals with the performance of contention-based medium access control (MAC) protocols for underwater sensor networks. We extensively analyze the number of received-packets and the end-to-end delay of ALOHA, CSMA, CSMA-RTS-CTS and CSMA-RTS-CTS-ACK protocols using a Qualnet underwater network simulator which accommodates diverse underwater acoustic channel environments. Using simulation results, we support an engineering table to determine an adequate contention-based MAC protocol for underwater sensor networks.

• International Commerce and Information Review
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• v.13 no.4
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• pp.101-124
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• 2011

This paper is framed for analyzing what the most significant factors are in Turkey, where the Korean investing enterprises should overcome and accomodate to the various barriers of management, especially in terms of network construction. The main purpose of this research is to test empirically some connections of between the managing strategy of network competitiveness by Korean enterprises and the management performances of Korean ones in Turkey while this is composed of two stages. First, the study model is planned by discussing relevant theories, previous studies and the current investment circumstances in local Turkey. Second, the survey of Korean enterprises participated in investment activities in there is practiced by gathering questionnaires. The strategic method of structural equation modeling is implemented to testing some hypotheses. Summing up partially, to maximize profits growth, Korean enterprises have been making application of the internal worker controlling as the means of network competitive advantages.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.2
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• pp.156-164
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• 2019

In this paper, we propose an efficient dynamic slot re-assignment scheme for swarming drone networks in which networks members merged and split frequently. The leader drone of each network recognizes the slot allocation information of neighbor networks by periodic information exchange among between the drones. Using the information, the leader drone makes a decision how to reallocate the slots between members in case of network merge. The non-competitive method in the proposed scheme can re-assign the slots without any slot collision and shows always superior performance than competitive scheme. The competitive method in the proposed scheme reduces the number of slots that should be re-assigned in case of network merge. The experimental performance analysis shows that the proposed scheme performs better or at least equal to the performance of the competitive scheme in a swarming drone network.

• Electronics and Telecommunications Trends
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• v.30 no.6
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• pp.68-78
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• 2015

우리의 일상생활 속에서 일어나는 수많은 일이 네트워크를 배제하고는 설명할 수 없을 정도로 삶과 밀접한 관계를 가지고 있다. 그러나 이러한 네트워크의 근간이 되는 국내 네트워크 장비 산업의 현실은 그리 낙관적이지 않다. 대표적인 이유로 핵심 소프트웨어인 네트워크 운영체제의 부재를 꼽는다. 이는 소프트웨어 개발 인력 부재, 투자 부족, 산업 경쟁력 약화, 매출 축소 등이 악순환의 고리로 연결되기 때문이다. 따라서 본고에서는 네트워크 산업 생태계의 회복과 이를 통한 네트워크 산업의 재도약을 위한 핵심 분야인 네트워크 운영체제의 기술동향을 살펴보고자 한다. 먼저 국내외 통신산업의 변화와 네트워크 운영체제 개발동향 및 네트워크 운영체제의 요구사항을 확인하고, 최근 주목받고 있는 개방형 네트워크 장비 개발동향를 소개한다. 그리고 국내외 네트워크 장비 시장에서 경쟁력을 확보하려는 방안으로 추진하고 있는 한국형 네트워크 운영체제(openN2OS)의 개발현황을 살펴본다.

• Journal of KIISE:Information Networking
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• v.34 no.6
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• pp.423-434
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• 2007

Vehicular ad-hoc network (VANET), a kind of mobile ad-hoc network (MANET), is a key technology for building intelligent transportation system (ITS). VANET is automatically and temporarily established through vehicle-to-vehicle communication without network infrastructure. It has the characteristics that frequent changes of network topology and node density are occurred and messages are disseminated through several relay nodes in the network. Due to frequent change of network topology and node density, however, VANET requires an effective relay node selection scheme to disseminate messages through the multi-hop broadcast. In this paper, we propose a contention window based multi-hop broadcast scheme for VANET. Each node has an optimized contention window and competes with each other for a relay node. The experimental results show that the proposed scheme has a better performance than the distance-based deterministic broadcast scheme in terms of message propagation delay and network traffic.

• Journal of the Korean Geographical Society
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• v.33 no.2
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• pp.309-324
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• 1998

본 연구는 급속한 기술변화와 경쟁심화에 의해 생산체계의 분화가 촉진되고 있는 컴퓨터산업을 사례로 기업간 네트워크의 형성실상과 요인을 분석하였다. 네트워크는 거래원리와 기업간 관계의 측면에서 정의되었으며 하청과 협력네트워크로 구분하였다. 설문조사 결과에 의하면, 하청네트워크는 약 75%, 협력네트워크는 약 85%의 기업이 참여하고 있어 어떤 형태로든 상당수의 기업이 네트워크를 형성하고 있다. 협력네트워크는 물론 하청네트워크도 거래기업간 보완성과 전문성에 의해 지속적인 거래관계로 형성되고 있다. 이것은 기업간 네트워크가 다층화된 생산체계에서 외부기업의 자원을 이용하여 경쟁력을 강화하는 기업전략임을 의미한다. 따라서 기업간 네트워크는 세계화-지방화 시대의 경제공간구조의 변화를 살펴볼 수 있는 중요한 지표가 될 수 있다.

• Journal of Korea Fair Competition Federation
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• no.54
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• pp.27-33
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• 2000

• Digital Contents
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• no.7 s.98
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• pp.30-37
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• 2001

서비스업자들은 선택의 기로에 놓여있다. 잘못된 선택이 그들을 파국으로 치닫게 만들지도 모른다. 많은 네트워크 전문가들은 지난 몇년간에 걸쳐 네트워크 분야는 많은 성장을 한 것은 사실이나 앞으로 다가오게 될 네트워크를 생각한다면 현재의 네트워크는 그 경쟁력을 상실하게 될 것이란 견해가 지배적이다. 이 말은 생존과 생존 이상의 성공을 원하는 서비스업자라면 자신의 경쟁력을 한껏 높여줄 기술을 제대로 선택해야 된다는 뜻이기도 하다. 현재 많은 기술들이 개발자와 사용자에게 있어 관심의 대상으로 떠오르고 있다.

• Journal of the Korean Academic Society of Industrial Cluster
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• v.1 no.1
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• pp.16-28
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• 2007

This paper analyzes the effects of networking and competition on individual companies' R&D investment, focusing on pharmaceuticals, PCB (Printed Circuit Board), and auto parts sectors. Data were obtained through a survey on firms operating in Seoul, Incheon, and Gyung-gi metropolitan area. The estimation results suggest the networking with other actors in the clusters tends to increase R&D investments of individual firm's. But competition in a cluster tend to reduce individual firm's R&D investment. These results suggest the public policy promoting networking in a cluster could induce private firms' R&D investments and, therefore, should be maintained.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1B
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• pp.24-33
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• 2009

This paper considers network competition where the subscribers experience network congestion when they use the network and the network providers determine the network price and capacity. This paper discusses the impact of the network competition on social welfare. Network provider determines the price and capacity considering this characteristics of this sensitivity to network congestion where the subscriber has different preference about the congestion. This paper shows that network provider who wants to serve the intolerable customers (who is very sensitive to the congestion) offers higher price and capacity. However, this provider prepares lower capacity than socially optimal capacity. This is because the network provider seeks to earn more profits from additional subscriber while it is desirable to invest the capacity to give the entire subscribers a non-congestion network in the view of social welfare.