• 베이커리
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• no.7 s.408
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• pp.126-129
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• 2002

• 베이커리
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• no.7 s.408
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• pp.133-135
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• 2002

• Journal of Broadcast Engineering
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• v.10 no.3
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• pp.372-382
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• 2005

DS/CDM-QPSK (ITU-R Recommendation BO.1130-4 Annex 6, 'Digital System E'), which has been adoptedas a standard of Korean Satellite DMB (Digital Multimedia Broadcasting) system, is a satellite-based multimedia broadcasting service which transmits the multi-channel and high quality contents to the terrestrial users through a satellite or gap-fillers. The broadcast from a satellite is directly received in the plain terrain which are within line-of-sight, but in cities where the broadcast cannot be received directly due to the shadow of buildings, an attempt is being made to install 'Gap-Fillers' to improve the reception in those areas. The gap-fillers, however, may induce interference to service of adjacent band, when their output power is substantially higher compared to the received signal power of signal from a satellite of the adjacent service. In this paper, a link budget analysis is performed, and the optimal EIRP of a gap-filler to maximize the gap-filler coverage, while preventing adjacent band interference is derived.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.1
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• pp.121-127
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• 2017

In the land mobile satellite (LMS) communication, a hybrid satellite-terrestrial relay networks (HSTRNs) using a maximal ratio combining (MRC) scheme are widely used to enhance the quality of signal from a satellite. In this paper, we derive equations for the TCP throughput and the spectral efficiency in the HSTRN and analyze results of the performance evaluation for TCP in various environments. In the simulation results, it is shown that increasing the number of terrestrial relays can enhance the TCP throughput and spectral efficiency thanks to the MRC scheme. However, the usage of the static number of terrestrial relays considering no channel states would cause the overhead. Furthermore, it has a limitation to enhance the network performance by only MRC scheme in HSTRN because the TCP performance is sensitive to the packet los rate. Therefore, we discuss the possible solutions that can additionally enhance the network performance and reduce the overhead.

• Journal of Broadcast Engineering
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• v.7 no.1
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• pp.10-20
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• 2002

In order to fill the gaps in DTV coverage, KBS Technical Research Institute has researched on DTV on-channel repeating systems as well as DTV translators. The on-channel repeater can reuse frequency resources for expanding service coverage. but it has also many restricts in applications for ATSC DTV system. Thiss Paper compares two kinds of DTV on-channel repealer systems and also presents field test results of both systems. From these results, we Infer their characteristics and summarize the conditions and possibilities of the application for our broadcasting networks.

• The Hankook-Saengyark Bo
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• no.220
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• pp.6-6
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• 1997

• 방재와보험
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• s.141
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• pp.2-3
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• 2011

• 방재와보험
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• s.142
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• pp.2-3
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• 2011

• 월간낙농육우
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• v.36 no.11
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• pp.122-132
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• 2016

2015년 감사원에서 지방교육청 감사 이후 교육부에 학교우유급식 공급업체 선정시 입찰을 실시할 것을 권고하면서 올해부터 학교우유급식 최저가 입찰제가 본격 확대됐다. 최저가 입찰제 시행 1년에 이른 지금, 유업체간 출혈경쟁으로 납품을 포기하는 사례가 발생하고, 터무니없이 낮은 가격은 급식우유의 품질을 의심하게 만들었으며, 도농간 우유급식 공급가격 격차가 발생, 칼슘 섭취 사각지대에 놓인 학생들이 오히려 많아지게 됐다. 본회 낙농정책연구소에서는 홍문표 국회의원, 김성원 국회의원과 함께 지난 10월 26일 국회의원회관 대회의실에서 토론회 "위기의 학교우유급식 '최저가 입찰제' 이대로 좋은가"를 개최하여 최저가 입찰제에서 야기된 부작용과 해결방안을 찾아보는 자리를 마련했다. 열띤 국회 토론회 현장을 지상중계한다.

• Bulletin of Food Technology
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• v.3 no.2
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• pp.95-105
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• 1990