고등어 낚시어장에서 150Hz~200Hz의 순음과 단속순음을 수중스피커로 수중에 방성하였을 때 고등어 어군의 반응과 어선의 보조기관의 수중소음을 측정\ulcorner분석한 결과를 요약하면 다음과 같다. 1. 보조기관만을 운전하였을 때 수중소음의 중심주파수와 음압레벨은 수심 20m에서 각각 500Hz, 146.8dB이었다. 2. 주파수 150Hz와 200Hz의 순음의 음압레벨은 수심 30m, 70m, 120m에서 각각 141.0dB와 146.6dB, 120.0dB와 126.6dB, 114.3dB와 120.5dB이였다. 3. 수중음을 방성해서 5분 전후에 고등어 어군이 유집반응을 보였다. 4. 주파수 150Hz와 200Hz의 순음보다는 단속순음이 좋은 유집반응을 나타냈다

A field experiment was carried out of confirm the effect of underwater sound on the luring of fish school of chub mackerel in the coast of Idousyo Island. Underwater sound that was made use of luring of fish school was pure sound and interval pure sound which the frequencies of the sound were 150Hz and 200Hz, respectively. The results of the observation of hooking and recording paper of fish finder indicate that the effect of emitting sound at 20m in the depth of water was remarkable for the luring of fish school of chub mackerel. The vertical pure sound pressure level at 150Hz and 200Hz of the water layer that was lured the fish school of chub mackerel were 140.1dB and 146.dB at 30m, 121.0dB and 126.6dB at 70m and 141.9dB and 120.5dB at 120m in the depth of water, respectively.

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