Acoustic method for discriminating plankton from fish in Lake Dom Helvecio of Brazil using a time varied threshold

시간변량역치를 이용한 브라질 Dom Helvecio호수의 어류와 플랑크톤 생물의 음향적인 구분을 위한 기법

  • Received : 2012.06.11
  • Accepted : 2012.10.29
  • Published : 2012.11.30


An acoustic method for discriminating plankton from fish, in Lake Dom Helvecio of Brazil, is developed. The flow of data from this method is comprised of time varied threshold (TVT), dilation filter, bitmap and mask functions. The TVT can, of itself, precisely explain how to select an appropriate value. The final results of the echogram, which only shows plankton by masking fish signals, is used to examine the acoustic density of plankton by depth and time. The results indicate that the acoustic density of the plankton is at a depth of between 5m to 15m, its density is especially high at 10m to 15m. The results of the acoustic density of plankton by time indicate that May 7 is higher in density than May 8. Future study plans include the use of net samples, environmental datasets to identify the abundance and ecology described by the Chaoborus spp. from other species.




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