• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.5
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• pp.373-386
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• 2024

The aim of this study is to establish a system for the early detection of high-density harmful marine organisms. Considering its accuracy and processing speed, YOLOv8m (You Only Look Once version 8 medium) is selected as a suitable model for real-time underwater image-based object detection. Applying the detection algorithm allows one to detect numerous fish and the occasional occurrence of jellyfish. The average precision, recall rate, and mAP (mean Average Precision) of the trained model are 0.931, 0.881, and 0.948 for the validation data, respectively. Also, the mAP for each class is 0.97 for fish, 0.97 for jellyfish and 0.91 for salpa, all of which exceed 0.9 (90%) for classes demonstrating the excellent performance of the model. A scientific sonar system is used to address the object-detection range and validate the detection results. Additionally, integrating and grid averaging the echo strength allows the detection results to be smoothed in space and time. Mean-volume back-scattering strength values are obtained to reflect the detection variability within the analysis domain. Furthermore, an underwater image-based object (marine lives) detection algorithm, an image-correction technique based on the underwater environmental conditions (including nights), and quantified detection results based on a scientific sonar system are presented, which demonstrate the utility of the detection system in various applications.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.10a
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• pp.9-18
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• 2003

현재까지 어종식별에 이용되어진 방법으로는 크게 4가지로 나눌수 있다. 1) 주파수특성법: 광대역 혹은 복수주파수에 의한 어군의 음향산란의 주파수특성의 차이를 이용하는 방법(Madureira et at., 1993; Simmonds et at., 1996),2) 분포특징법 :어군형태와 분포특성에 근거한 방법 (LeFeuvre et at., 2000), 3) 신호특징법: 어군에코의 포락선등의 신호의 특징에 근거한 방법Rose and Leggett, 1988; Scalabrin et at., 1996), 4) 음향결과법: SV, TS, 에코트레스해석에 의한 유영속도 등 과학어탐에 의해서 얻어진 정보를 이용한 방법이 있다 (Richards et al., 1991). (중략)