• Title/Summary/Keyword: 레이더반사기

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A Study on the Lights and Shapes for the Small Fishing Vessel and the Vessels Towing and Being Towed (소형어선 및 예인선단의 등화 및 형상물에 관한 고찰)

  • Chong, Dae-Yul
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.4
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    • pp.421-427
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    • 2015
  • This study aims at reviewing first the cases of marine accidents of small fishing vessels and vessels towing and being towed and, the problems concerning such lights and shapes that could be misunderstood for those in concerned Rules, or that could impair their distinctive characteristics or obstruct to keep a proper look-out. And then I wish to make a suggestion of the necessity of amending the National Laws which stipulate the rules for the ship's lights and shapes as follows; Firstly, by amending the "Standard of Construction and Equipment for the Less Than 10 Gross Tonnage of Small Fishing Vessels" small fishing vessel must be equipped with the lights and shapes that are the same as those of "vessel engaged in fishing" prescribed by Rule 26 of the "COLREG 1972" and Rule 84 of the "Maritime Safety Law Act". Secondly, "Standard of Fishing Vessels Equipment" which stipulate the rules concerning the exception of the running lights and radar reflector for the small fishing vessels must be amended to meet the requirement of Rule 20 of the "Maritime Safety Act". Thirdly, the definition of "Length of the tow" which prescribed by Rule 2 of the "Maritime Safety Act" must be amended to meet the Rule 24 of the "COLREG 1972". And also I wish to adhere to the importance of displaying the adequate vessel lights and shapes by every mariner for preventing marine accidents.

Analysis of the Radiation Patterns of Satellite SAR System with Active-Transponder (능동전파반사기를 이용한 위성 SAR 시스템 방사 패턴 분석)

  • Hwang, Ji-Hwan;Kweon, Soon-Koo;Oh, Yisok
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.10
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    • pp.1204-1211
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    • 2012
  • Measurement and analysis results of the extracted radiation-patterns from the field-experiments which were conducted to acquire the generic technology for calibration and validation of the satellite SAR system(Synthetic Aperture Radar) are presented in this study. Prototype of active transponder is adjustable within maximum 63.1 dBsm of RCS (Radar Cross Section) and includes the receiving-function with external receiver. To increase an accuracy of these field experiments, we repetitively measured satellite SAR systems of the same operating mode(i.e., COSMO-SkyMed No. 2 & 3, hh-pol., strip-map himage mode, 3 m resolution). Then, the reliability of experimental results was cross-checked through analysis of the RCS of active transponder on SAR image. The property of azimuth radiation patterns of satellite SAR system extracted from them has $0.352^{\circ}$ of HPBW(half-power beamwidth), $0.691^{\circ}$ of FNBW(first-null beamwidth), and 11.17 dB of PSLR(peak to side lobe ratio), respectively.