• Title/Summary/Keyword: Re-transmission

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Adaptive QoS-based system design for Video On Demand Service. (Video On Demand 서비스의 QoS 적응적인 시스템 설계에 관한 연구.)

  • 정혜동;서원범;최지훈;서덕영
    • Proceedings of the IEEK Conference
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    • 2000.09a
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    • pp.979-982
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    • 2000
  • In this paper we suggest the adaptive QoS-based VOD system design, which can diagnose and reflect the variable network situation. This system is based on the changeable Forward Error Correction(FEC) coding and re-transmission to enhance system quality by using the measured real-time network value such as loss, delay and jitter.

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Oral tuberculosis - a brief review - (임상가를 위한 특집 1 - 구강 결핵 감염 - a brief review -)

  • Ryu, Mi-Heon
    • The Journal of the Korean dental association
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    • v.48 no.5
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    • pp.350-354
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    • 2010
  • Tuberculosis has re-emerged as serious infectious diseases, and oral tuberculosis, though uncommon, can be seen in both the primary and secondary tuberculosis. The aim of the present review is to describe the pathogenesis of tuberculosis and the characteristics of oral tuberculosis. The oral tuberculosis lesion may present as a diagnostic challenge for the clinician. In particular, the risk of tuberculosis transmission in dental practises is potentially increasing, the dentists and dental providers must exercise strict tuberculosis prevention.

Study on the stabilisateur of information transmission in RF-CBTC train control system using the FHSS system (FHSS방식을 채용한 RF-CBTC 열차제어시스템 정보 전송의 안정화에 관한 연구)

  • Oh, Sea-Hwa;Jin, Zhe-Huan;Lee, Key-Seo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.9 no.4
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    • pp.455-468
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    • 2014
  • This paper presents seamless hand off implementation suggesting algorithm and Measuring /testing at the tunnel environment in order to derive the ideal value of wireless data transmission in RF-CBTC train control system modeled by Shinbundang Operation System. In addition, it proposes the ideal value(-57dB) for reducing the re-transmission or frequency interference rate and demonstrates frequency optimization which enables highly reliable data communication in Train control system using wireless communications. Based on these result, Shinbundang phase 2 plan to apply to this system.

A Packet-Loss Resilient Packetization and Associated Video Coding Methods for the Internet Video Transmission (인터넷 동영상 전송을 위한 패킷손실에 강인한 패킷화 및 동영상부호화 기법)

  • Yoo Kook-yeol
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.11C
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    • pp.1068-1075
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    • 2005
  • In this paper we propose a video coding method and associated packetization and decoding methods for error resilient transmission over the Internet. The proposed method re-organizes the input image into several mutually similar subimages. For this case, if the one of the subimage is lost in the network, the lost one is recovered by the proposed error concealment method which uses the correctly received other subimages. The performance of the proposed method is confirmed by the empirical results. The proposed method is not limited to the Internet communications but is applicable to the other packet-based networks.

A Study on the Effect of Redundant Transmission and Interleaving for WLAN Internet Local Broadcasting (무선랜 인터넷 지역 방송에서 복수전송과 인터리빙 효과 연구)

  • Oh, Jongtaek
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.6
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    • pp.43-48
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    • 2012
  • In As the proliferation of wireless LAN and smart devices like smart phone, the importance of the wireless Internet local broadcasting service is increasing. In order to provide broadcasting data for the multiple devices, one-way roadcasting technology which could not support re-transmission, should be used and the receiving frame error is major problem. Furthermore unlicense devices cause interference to the receiver, burst frame error tends to be happened. In this paper, new method to overcome the burst and random frame error is proposed and the effect is analyzed.

A study on the ice and snow loading condition in Taebaek and Sabuk area in Gangwon province for the construction of KEPCO 765kV transmission lines (한전 765 kV 송전선로 건설을 위한 강원도 태백.사북지역 착빙설 하중조건 검토)

  • Park, K.H.;Kim, Y.W.;Won, B.J.
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1923-1924
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    • 1996
  • Some part of the route in KEPCO 765kV transmission line being constructed passes through a high mountain area which is 800m above the sea level (Taebaek, Sabuk area in Gangwon province). This area is the top part of Taebaek mountains corresponding to the backbone of korean peninsula and has lots of snow during the winter season because the winter seasonal wind gone up along the mountainside of Taebaek Mts. meets open air of the East sea. KEPCO has experienced 63 faults of T/L between 1968 and 1993 in this area, which is a very serious problem. Especially 154kV Hwang-Ji T/L fault in 1990, 2 was a unprecedented case which needs to be analyzed carefully to take proper measures. After reviewing ice and snow loading conditions and analyzing the fault of Hwang-Ji T/L, we're going to determine the revisement of ice and snow loading condition in this area to increase reliability of 765kV transmission line.

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WATM MAC Protocol using Adaptive Request Mini-slots (적응적 Request Mini-slots을 이용한 WATM MAC 프로토콜)

  • 문홍진;장성현
    • Journal of Korea Multimedia Society
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    • v.6 no.5
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    • pp.831-841
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    • 2003
  • In wireless ATM network, Mobile terminals must offer function and QoS such as terminal of wire ATM network. The fast notification of BS (Base Station) scheduler about ATM cells arriving in mobile terminals is a critical item of the ATM-based centrally controlled MAC protocol. But, Collision is arisen at process that several mobile terminals require data transmission by contention method through uplink and because of re-transmission by collision, throughput of decrease and transmission delay increases. In this paper, We propose the MAC protocol that decide optimized request mini-slot's number considering number of request terminal predicted as statistical and its posterior throughput. According to simulation result, could know that proposed protocol shows high performance delay and throughput.

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Direction of Policy for Wireless Power Transmission Industry to Adapt Changes of the Future (미래에 대응하기 위한 국내 무선전력전송 산업방향 정책제언)

  • Yun, Jae-hoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.26 no.8
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    • pp.699-709
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    • 2015
  • The role of wireless power transmission(WPT) on the information communication technology and the re-set location of WPT technology in the hype cycle to apply the recent trend of market and industry are presented in this paper. We describe the need of national strategy to change from the phase of industry promote to the phase of industry revitalization. The relation between the management of spectrum and electromagnetic environment is analysed in the view point of physics. We also propose the direction of policy for industry revitalization adapted the world changing circumstance.

A Study of WAP Packet using Turbo Code Scheme in Bluetooth piconet Environment (블루투스 피코넷 환경에서 터보코드 기법을 이용한 WAP 패킷의 연구)

  • Moon, Il-Young;Cho, Sung-Joon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.553-556
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    • 2005
  • It is analyzed that WAP packet transmission time to improve performance of WAP using SAR algorithm in Bluetooth channel. The order for SAR algorithm to improve the transfer capability, it is fragmented in WTP total messages that are coming down from upper layer and then the packets are sent one at time in baseband. And it is studied that transmission time for WAP over bluetooth according to DM1, DM3 or DM5 packet type using SAR algorithm in Bluetooth piconet environment. This SAR algorithm decreases WAP packet transmission time of L2CAP baseband packets by sending packet which are spanning multiple slots.

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