• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.691-693
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• 2015

Radio sources are very weak, as they can travel through large distances. Radio sources also have photons with low energies compared to others electromagnetic waves (EM). Microwave photons have a little more energy than radio waves, infrared photons have still more, then visible, ultraviolet, X-rays, and the most energetic electromagnetic wave is gamma-rays. Radio astronomy studies are restricted due to radio frequency interference (RFI) produced by people. If this disturbance is not minimized, it poses critical problems for astrophysical studies. The purpose of this paper is to profile RFI maps in Peninsular Malaysia with a minimum mapping technique for RFI interference. Decision-making processes using GIS (Geographical Information System) for the selection requires gathering information for a variety of parameters. These factors affecting the selection process are also taken into account. In this study, various factors or parameters are involved, such as the availability of telecommunications transmission (including radio and television), rainfall, water lines and human activity. This mapping step must be followed by RFI site testing in order to identify areas of low RFI. This study will benefit radio astronomy research, especially regarding the RFI profile.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.11
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• pp.3780-3797
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• 2022

The estimation of radio map (RM) is a fundamental and critical task for the network planning and optimization performance of mobile communication. In this paper, a RM estimation method is proposed based on a deep dual learning structure. This method can simultaneously and accurately reconstruct the urban building map (UBM) and estimate the RM of the whole cell by only part of the measured reference signal receiving power (RSRP). Our proposed method implements UBM reconstruction task and RM estimation task by constructing a dual U-Net-based structure, which is named RadioCycle. RadioCycle jointly trains two symmetric generators of the dual structure. Further, to solve the problem of interference negative transfer in generators trained jointly for two different tasks, RadioCycle introduces a dynamic weighted averaging method to dynamically balance the learning rate of these two generators in the joint training. Eventually, the experiments demonstrate that on the UBM reconstruction task, RadioCycle achieves an F1 score of 0.950, and on the RM estimation task, RadioCycle achieves a root mean square error of 0.069. Therefore, RadioCycle can estimate both the RM and the UBM in a cell with measured RSRP for only 20% of the whole cell.

• Broadcasting and Media Magazine
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• v.21 no.3
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• pp.61-83
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• 2016

현재 유럽과 미국을 중심으로 하이브리드 라디오 서비스 도입을 위한 표준 및 기술 개발이 진행 중에 있다. 하이브리드 라디오는 기존 라디오 방송망과 통신망을 결합하여 스트리밍 서비스 및 고품질 부가 데이터 서비스를 제공할 수 있는 특징을 가진다. 본 고에서는 RadioEPG에서 개발을 진행 중인 RadioDNS lookup, RadioVIS, RadioEPG, RadioTAG, RadioWEB 표준 및 기술 개발 동향을 소개하고자 한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2017.11a
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• pp.185-186
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• 2017

본 논문에서는 최근 논의되고 있는 하이브리드 라디오 방송 기술을 자동차에서 상용화 하기 위해서 개발된 Xperi 사의 DTS Connected Radio 기술을 개략적으로 소개한다. DTS Connected Radio 는 방송망으로 수신된 아날로그 혹은 디지털 라디오와 IP 망을 이용하여 받은 방송 프로그램 정보 및 현재 방송되고 있는 음악에 대한 정보 등의 추가적인 정보를 차량에서 같이 제공하는 서비스를 말한다.

• The Bulletin of The Korean Astronomical Society
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• v.24 no.1
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• pp.50-50
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• 1999

• Bulletin of the Korean Space Science Society
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• 2007.10a
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• pp.57.2-57.2
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• 2007

• The Bulletin of The Korean Astronomical Society
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• v.23
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• pp.44-44
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• 1998

• The Bulletin of The Korean Astronomical Society
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• v.23
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• pp.58-58
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• 1998

• The Bulletin of The Korean Astronomical Society
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• v.16
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• pp.12.3-13
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• 1991

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1568-1569
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• 2005

This paper presents a method to optimize train radio communication network for train control(CBTC) or multimedia services. To determine the optimized distance between wayside radio stations in a radio communication network constructed along railway, radio frequency allocation and hand-over capability is studied in terms of radio communication cell coverage and roaming feasibility.