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Short-Term Variability Analysis of the Hf-Radar Data and Its Classification Scheme

HF-Radar 관측자료의 단주기 변동성 분석 및 정확도 분류

  • Choi, Youngjin (GeoSystem Research Corporation) ;
  • Kim, Ho-Kyun (Oceanographic Forecast Division, Korea Hydrographic and Oceanographic Agency) ;
  • Lee, Dong-Hwan (GeoSystem Research Corporation) ;
  • Song, Kyu-Min (Ocean Circulation and Climate Research Center, Korea Institute of Ocean Science & Technology) ;
  • Kim, Dae Hyun (OCEANTECH Co.)
  • 최영진 ((주)지오시스템리서치) ;
  • 김호균 (국립해양조사원 해양예보과) ;
  • 이동환 ((주)지오시스템리서치) ;
  • 송규민 (한국해양과학기술원 해양순환기후연구센터) ;
  • 김대현 (오션테크(주))
  • Received : 2016.10.11
  • Accepted : 2016.12.15
  • Published : 2016.12.31

Abstract

This study explores the signal characteristics for different averaging intervals and defines representative verticies for each observatory by criterion of percent rate and variance. The shorter averaging interval shows the higher frequency variation, though the lower percent rate. In the tidal currents, we could hardly find the differences between 60-minute and 20-minute averaging. The newly defined criterion improves reliability of HF-radar data compared with the present reference which deselects the half by percent rate.

HF-Radar관측자료의 시간평균 간격에 따른 신호특성을 살펴보고, 국립해양조사원에서 운영하고 있는 HF-Radar관측소별로 수집률과 공분산을 분석하여 자료질이 높은 대표정점을 선점(選點)하였다. HF-Radar관측의 시간평균 간격이 짧아질수록, 취득률은 낮아지나 고주파 신호특성을 관측할 수 있었다. 그러나 조류예측에서는 현행 60분 간격의 평균자료와 20분 간격의 자료에서 취득되는 조류의 차이는 거의 없었다. 수집률 기준을 높이고 공분산을 고려한 자료는 기존에 수집률 50%만을 기준으로 한 정점에 비해 관측품질이 높아졌다.

Keywords

References

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