• Title/Summary/Keyword: Swimbladderless

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Acoustical backscattering characteristic depending on the changes in the body of sandfish (Arctoscopus japonicus) (도루묵의 체내 변화에 따른 음향산란특성)

  • YOON, Eun-A;LEE, Kyounghoon;HWANG, Kangseok;LEE, Hyungbeen;HAN, Inwoo;HWANG, Doo-Jin
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.52 no.1
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    • pp.36-41
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    • 2016
  • Changes in target strength (TS) values of sandfish when sandfish was alive and dead were investigated using ex-situ at 120 kHz. TS values measured by tilt angles with -50~+50 degrees showed ranges from -71.0 to -53.3 dB for live sandfish, -63.1~-46.3 dB for thawed sandfish, and -70.0~-50.4 dB after 24 hours from thawed, respectively. It was shown that while TS values were similar between the case of live and the case of after 24 hours from thawed, mean TS values were higher by approximately 5 dB in the case of immediate thawed sandfish. It was also seen that TS values were similar between the case of thawed sandfish and the case of after 21 hours from live. The results showed that TS values of live sandfish were different from those of frozen sandfish. It implies that when estimating TS of frozen fish, the influx of bubbles and changes of body should be considered.