SIUDIES ON THE STATISTICAL MODEL OF THE COCOON CONSTRUCTION PROCESS AND SHAPE CHANGE OF SILKWORM'S BODY

按照我们的研究计划，在不同品种的家蚕上进行了一些试验。然后利用自行开发的家蚕行为分析三维计算机图形系统（3DASBS）对实验数据进行分析。此外，我们还尝试用随机模型来描述家蚕的行为。获得了以下结果。(1)吐丝区的尺寸变化：将吐丝孔的位置拟合成椭球体，首次用数值方法显示了结茧过程中吐丝区的尺寸变化。(2)拉伸行为：由于在产生具有显著收缩部分的茧的物种中更经常观察到拉伸行为，我们认为这种行为是茧中心出现收缩部分的一个因素。(3)家蚕身体的形状变化：布克斯坦的形状变量用于几个物种之间的比较。此外，利用Kullback信息量对不同种间的距离进行了估计。(4)蚕体形状的概率分布：将形状分布近似视为正态分布，并考虑了形状参数的估计方法。(5)球面上的统计模型为Fisher或肯特分布，分析了球面上的方向性。

Some experiments were conducted on various species of silkworms following our research plan. Then experimental data were analyzed by using our 3DASBS (Three-dimensional Computer Graphics System for Analysis of the Behavior of Silkworm). Furthermore, we tried to represent silkworm behavior by stochastic model. Following results are obtained.(1) Size change of the spinning region : Fitting an ellipsoid to the positions of the orifice of spinneret, we could show for the first time numerically the size change of the spinning region in the cocoon construction process.(2) Stretching behavior : Since stretching behavior was more often observed in the species producing a cocoon with a remarkable constricted part, we thought this behavior was one factor for the appearance of a constricted part in the center of a cocoon.(3) Shape change of a silkworm's body : Bookstein's shape variables were used for the comparison among several species. In addition, the distances between different species were evaluated by Kullback's information.(4) Probability distribution of the shape of a silkworm's body : Shape distribution was approximately regarded as a normal distribution and estimation method was considered for the shape parameters.(5) Statistical model of the direction of the spinneret : Fisher or Kent distribution was used as the statistical model on the sphere and the directional properties of the spinneret were analyzed.