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At Cataract Creek, situated about 15 km north of Wollongong, NSW Australia, a small transient electromagnetic (TEM) profile anomaly over conductive cindered coal is totally obscured by 50 Hz noise measured at stations near power lines. A remote noise prediction filter (RNPF) based on simple scaling and phase correction of the remote noise to match the local noise was tested. A profile anomaly obscured by 50 Hz noise can be recovered with the application of this filter. The remote reference filter is not affected by changes of noise frequency or amplitude, since the changes are monitored by simultaneous measurements at the remote receiver and can be allowed for during the noise filtering process.
호주 NSW주, Wollongong시에서 북쪽으로 15 km에 위치한 Cataract Creek에서 측정된 시간영역 전자탐사(transient electromagnetic: TEM) 반응값들은 측점의 인접지역을 통과하는 전력선에서 야기된 50 Hz 전자기잡음에 의해 심하게 왜곡되었다. 이 연구에서는 전력선 잡음제거를 위해 원거리잡음예측필터(remote noise prediction filter: RNPF)를 시험하였으며, 이 RNPF는 원거리잡음과 근거리잡음간의 단순한 비율보정(simple scaling correction)과 위상보정(phase correction)에 기초를 두었다. 50 Hz 전자기잡음에 의해 심하게 왜곡되어 인지할 수 없었던 석탄층에 대한 TEM 이상대를 RNPF필터의 적용으로 복구하였다. RNPF필터의 장점은 전자기잡음원의 진폭이나 주파수의 시간적 변화가 필터의 성능에 어떤 영향도 미치지 않는다는 것이다.
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- Publisher :The Korean Society of Mineral and Energy Resources Engineers
- Publisher(Ko) :한국자원공학회
- Journal Title :Journal of the Korean Society for Geosystem Engineering
- Journal Title(Ko) :한국지구시스템공학회지
- Volume : 45
- No :3
- Pages :242-248
Journal of the Korean Society of Mineral and Energy Resources Engineers
