• Journal of the Institute of Convergence Signal Processing
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• v.12 no.2
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• pp.102-106
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• 2011

The transfer capability of HFC (Hybrid Fiber Coax) network is superior to xDSL. HFC network, however, is not suitable for transferring high quality video due to cable model interfaces. For the services of high quality IPIV or VOD, the extra exclusive downstream transfer system is required without upgrading pre-equipped cable modem and service capability. This paper is aimed to develop the extra exclusive downstream transfer system not changing existing cable modem system but providing same quality of services. This system is composed of the extra exclusive downstream IP-cable sender and modem. This sender and modem have 30 Mbps transfer capability and HDTV stream can be served in the Cable TV network using 21 Mbps HDTV transport stream.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.331-335
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• 2007

방송과 초고속인터넷 서비스를 동시에 제공할 수 있는 HFC(Hybrid Fiber Coaxial) 망은 상/하향이 비대칭 구조이며, 하향속도에 비해 상향속도가 1/10 수준이어서 상향 트래픽이 과다하게 생성될 경우 인터넷속도 지연이 발생한다. 지연에 민감한 VoIP 서비스의 품질보장 방안으로는, DOCSIS(Data Over Cable System Interface Specification) 1.1 기반의 상향 스케쥴링 기능을 이 용한 VoCM(Voice Over Cable Modem)이 있다. 그러나 별도의 VoCM을 사용해야 하며 아날로그 전화기를 사용해 IP 기반의 VoIP 단말을 사용할 수 없다는 단점이 있다. 일반 CM(Cable Modem)에 DOCSIS 1.1 Config File을 이용하여 VoIP 품질을 보장할 경우 별도의 트래픽 대역을 항상 점유해야 하는 단점이 있다. 이에, 본 논문에서는 효율적 대역폭 이용과 단말장비에 종속적이지 않은 방안을 제안하고 일반 CM을 통한 유무선 환경하에서 Dynamic QoS(Quality Of Service)를 제공할 수 있는 PCMM(Packet Cable MultiMedia) 적용 방안 및 시험결과에 대해 고찰하고자 한다.

• Proceedings of the Korean Information Science Society Conference
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• 2008.06d
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• pp.121-125
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• 2008

본 논문은 Cable Modem이 Embedded되어 양방향 서비스가 지원되는 방송수신장치인 양방향 Digital Cable수신기의 IP기반의 Network응용프로그램인 SNMP(Simple Network Management Protocol)를 이용하여 원격지에서 센서 데이터를 실시간 모니터링하고 Processing 할 수 있는 시스템 개발에 관한 것이다. 센서는 양방향 Digital Cable수신기의 하나의 장치로서 인식되며 원격지의 Management Server에 센서데이터를 전송 할 수 MIB(Management Information Base)객체로 존재하게 되며 Digital Cable 방송수신장치는 시스템에 대한 정보나 센서데이터에 관한 정보를 전송할 SNMP Agent를 보유하게 되어 케이블 네트워크에서 정보의 전달이 가능하게 된다.

• The KIPS Transactions:PartD
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• v.9D no.1
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• pp.145-152
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• 2002

Recently most of the home and small-size company use ADSL(Asymmetric Digital subscriber Line) or Cable Modem for using Internet Services. The number of Internet IP Address in current Internet IP Address System(IPv4) that is consisted of 4byte is almost empty, so generally the IP Address assigned dynamically is used. This way is just OK in general uses, but not OK in Internet Servers operation. This paper designed the gateway(Gate-D) system which is enable any system that get IP Address assigned dynamically to serve Internet Server Services(Telnet, FTP, HTTP, Mail, etc …), and made sure the worth by using Telnet Server.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.8
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• pp.1597-1603
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• 2017

The incidence of fire in underground utility tunnel is lower than other fires, but the damage caused by fire can cause social loss due to social management paralysis as well as economic loss. Hereupon, this paper presents the results of an empirical test on the construction of the underground utility tunnel condition monitoring system using the leakage coaxial cable installed in the underground utility tunnel. For this reason, a verification test was conducted by connecting a inductive coupler 200 Mbps power line communication modem with insertion loss characteristics of $-6{\pm}2dB$ to the installed the leakage coaxial cable installed in the underground utility tunnel. As a result, We confirmed sending/receiving of IP cameras up to 500 m. Therefore, it is judged that it is possible to construct a condition monitoring system for underground utility tunnel by using the leakage coaxial cables installed in the underground utility tunnels without installing additional communication lines for data transmission.