• Title/Summary/Keyword: Communications media

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The regional information index in major cities of korea (지역정보화 정책 수립을 위한 지역정보화지수 작성에 관한 연구)

  • 지경용
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.2
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    • pp.381-391
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    • 1997
  • This study aims at designing and calculating of the information index for efficient implementation of the regional information policy. The content and scope of this study are designing the struture of information index, measuring the informatization level in major cities of Korea and inducing rough idea for better performing of Korea information policy. Thereby we calculated tables ofinformation indexon seventy-eight cities in Korea from 1985 to 1994 and also basic strategy for better policy implementation. And we found that every citities share the benefit almost equal in the use of old media but not in that of new media. It can be expected that the bovernment will make a good use to get procedural validity in the course of designing some information policy based upon quantitative data.

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RECONSTRUCT10N AND NAVIGATION OF CYLINDRICAL OBJECTS FROM MEDICAL IMAGES

  • Park, Yoo-Joo;Kim, Myoung-Hee;Min, Kyung-Ha
    • Proceedings of the Korea Society for Simulation Conference
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    • 2001.10a
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    • pp.223-230
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    • 2001
  • This paper proposes a new contour detection method and adaptive reconstruction scheme for the cylindrical organs, such as blood vessels or arteries. Furthermore, we present java-based navigation controller which has been built to examine the inside of cylindrical objects. Tn the preprocessing procedure, a few preprocessing image filters are applied in order to remove unwanted artifacts from the medical images and to estimate threshold values for the object of interest. We define a context-free grammar, which is proper fur properties of contours of cylindrical objects. In the next procedure, we extract contours using advanced radial gradient method and represent contours as context-free grammar derivation trees. We build polygons between two contours efficiently by traversing the derivations trees of the contours. We fly through the reconstructed virtual models using java-based navigation controller and VRML viewer.

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A Study on the Performance Analysis and Comparision of Channel Access Protocols in LAN (LAN에서 채널 접속프로토콜의 성능해석 및 비교에 관한 연구)

  • 김평육;김정선;이대영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.11 no.6
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    • pp.402-410
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    • 1986
  • The Media Access Control(MAC) Technologies in IEEE 802 Local Area Network(LAN) reference model include CSMA/CD, Token Ring and Token Bus methodes. The channel throughput of LAN can be affected by some parameters such as channel length, transmission rate and packet size, and station numbers. In this paper, the effect of these parameters to channel throughput are analyzed by normalized parameters. And the token ring and token bus method are analyzed by using the normalized parameter, and relatinonship bwtween channel thorughput and parameters is discussed. Finally, results are compared.

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A study on random access protocol based on reservation access for WDM passive star coupler network (WDM passive star coupler 망에서 예약 방식에 기반한 임의 접근 프로토콜에 관한 연구)

  • 백선욱;최양희;김종상
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.4
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    • pp.893-910
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    • 1996
  • Recently, there ary many researches on local area multichannel network as WDM technology developes. An ideal media access protocol in a multichannel network is one that shows short access delay under low load and high throughput under heavy load. This paper proposed a new media access protocol for WDM passive star coupler network. The proposed one is a random access rpotocol based on reservation. Access delay is short under low load by using random access method, and high throughput is achieved under heavy load by usin greservation access. Analytic model for the performance analysis of the proposed protocol is developed and performance of the proposed protocol is compared with the previous ones. The effect on the performance of the number of the nodes and channels, and the number of transceivers in each node are analyzed.

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Minimum Energy Cooperative Path Routing in All-Wireless Networks: NP-Completeness and Heuristic Algorithms

  • Li, Fulu;Wu, Kui;Lippman, Andrew
    • Journal of Communications and Networks
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    • v.10 no.2
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    • pp.204-212
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    • 2008
  • We study the routing problem in all-wireless networks based on cooperative transmissions. We model the minimum-energy cooperative path (MECP) problem and prove that this problem is NP-complete. We hence design an approximation algorithm called cooperative shortest path (CSP) algorithm that uses Dijkstra's algorithm as the basic building block and utilizes cooperative transmissions in the relaxation procedure. Compared with traditional non-cooperative shortest path algorithms, the CSP algorithm can achieve a higher energy saving and better balanced energy consumption among network nodes, especially when the network is in large scale. The nice features lead to a unique, scalable routing scheme that changes the high network density from the curse of congestion to the blessing of cooperative transmissions.

Tracking High-speed Moving Object Using Infrared Stereo Camera and Regression Analysis Using Artificial Neural Network (적외선 스테레오 카메라를 이용한 고속 이동체 추적과 인공신경망을 이용한 회귀분석)

  • Kim, Chanran;Lee, Jaehoon;Lee, Sang Hwa;Park, Jong-Il
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2017.11a
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    • pp.164-165
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    • 2017
  • 본 논문에서는 고속의 이동체를 추적하기 위하여 적외선 스테레오 카메라 시스템을 이용하였다. 열원을 감지할 수 있는 적외선 카메라를 이용해 고온의 추진체를 찾는다, 그리고 고속 이동체의 3 차원 위치를 계산하기 위해 스테레오 카메라 시스템을 사용하여 카메라와 고속 이동체 사이의 거리를 계산하였다. 마지막으로 인공신경망을 이용한 회귀분석으로 고속 이동체의 궤적을 추정하였다. 제안한 시스템이 동작하는 것을 실험 결과를 통해 보인다.

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Multidemia Communications System on the Ingernet

  • Kim, Hyun-Joon;Lee, Huen-Joo
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1998.06b
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    • pp.85-91
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    • 1998
  • Many of the newest network suers are gaining their fist network experience as users of the Internet. Because of the universal nature of this exciting new experience, millions of new users are driving the demand for increasingly multimedia oriented applications, especially in communication area. Since the communication via the Internet can use various media forms including audio, video and graphics, it can e very efficient communication system on the Internet, which allows Internet users to communicate, collaborate, and associate with others. Webber provides various communication services, like ACS(Audio Conference System), VCS(Video Conference System) and Virtual Space, in an integrated environment. Webber consists of Service-PUBs(Processing Unit Plug-in), which process each service, and Framework, which manages these PUPs. PUP is so highly independent of each other that it's easy to add, maintain, delete services and also optimally configure the system to user's terminal performance or network status.

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The Study of the Automation Systems using Satellite Communications (위성통신을 이용한 자동화 감시 시스템 구축 연구)

  • Kim, Myong-Soo;Hyun, Duck-Hwa;Cho, Seon-Ku;Kim, Choong-Hwan
    • Proceedings of the KIEE Conference
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    • 2002.07d
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    • pp.2540-2542
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    • 2002
  • In recent years, it is a worldwide trend that many power utilities focus their attention to employ up-to-date communication technology to the automation of their power plants and distribution systems. Automation Systems in Korea was installed using twisted pair cable(TPC), power line carrier(PLC), coaxial cable(CA), wireless network(wireless data, TRS and PCS). Among the communication media only Satellite Communication guarantees the reliable communication in case of emergency such as a flood, a heavy snow and an earthquake. It can integrate two-way satellite systems to existent nationwide SCADA controlling points of electric power transmission & distribution system that enables real time remote monitoring and controlling automatically. This paper presents some of design efforts for the satellite communication network as the media of Automation Systems.

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A Comparative Study on Usage Motivation and Satisfactions of Enterprise Micro-blog between Korea and China (기업 마이크로블로그 이용 동기 및 만족의 한중 비교연구)

  • Jun, Byoung Ho;Kim, Jung;Kang, Byung Goo
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.1
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    • pp.177-188
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    • 2013
  • As the number of smart phone users increases, many organizations begin to adopt social media rapidly to diversify communication channels with customers. Specifically, micro-blog, which supports instant and two-way communications between users and between organizations and users, has been adopted by many organizations as an efficient way not only to identify new customers but also to retain existing customers. The purpose of this study is to investigate the usage motivation and satisfaction of enterprise twitter based on use and gratifications perspectives comparing with Korea and China. Based on prior studies on use and gratifications of internet-related media, information seeking, pleasure/entertainment, relationship, communication, and incentives were identified as usage motivations of enterprise Micro-blog. This study contributes to provide the base of activation strategies and practical implications for micro-blog as a marketing tool.

IEEE 802.21 Media Independent Handover 기술 및 표준화 동향

  • Ji, Jeong-Hun;Kim, Eun-A;Park, Chang-Min
    • Information and Communications Magazine
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    • v.26 no.2
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    • pp.31-37
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    • 2009
  • 이기종 네트워크간 수직 핸드오버(Vertical Handover)를 이용하여 심리스 이동성을 제공하기 위한 IEEE 802.21 MIH (Media Independent Handover) 기술이 최종 표준 발간을 목전에 두고 있다. 이기종 네트워크간 핸드오버 시 끊김없는 고품질의 통신 서비스를 서비스 이용자에게 제공하기 위해서는 하부의 물리 및 MAC 계층과 상위의 이동성 프로토콜 상호간에 효과적인 정보가 적절한 시점에 전달되어야 한다. 본 고에서는 급속히 팽창하고 있는 이기종 네크워크간의 수직 핸드오버 서비스 시장 현황을 살펴보고, 이들 시장 상황에 효과적으로 적용할 수 있는 IEEE802.21 MIH 표준의 주요 핵심 기술 및 최근 표준화 이슈에 대하여 정리한다.