ティラピアの魚群行動モデルにおける前方推進機構の検討

Abstract

This paper describes the function of propulsive mechanism of tilapia Tilapia mossambica and improves the residual function in the fish behavior model. In the fish behavior model, the propulsive mechanism is the first component external force for the motion, which consists of the propulsive force and the drag force. The swimming velocity of tilapia increases approximately inversely proportional to its acceleration. Therefore the propulsive mechanism of tilapia can be expressed as a linear equation of velocity, i. e., Fi1=ai-vfivi, where ai, vfi and vi denote the propulsive parameter, drag parameter and the velocity. Although the quick whiteness tests of the residual was passed, the distribution of the residual was sometimes different from the normal distribution. The residual function assumed to be expressed as the equation of the two combined normal distributions. The swimming trajectory of fish in the simulation by the model including the new concept was consistent with that in observation.