说明：  功能：该程序用于仿真截断正态概率下舰艇机动加速度均值与方差的关系，输入：舰艇的最大机动加速度，输出：两幅加速度均值与方差的关系图。
(Features: The program for the simulation of truncated normal probability of ship maneuvering the relationship between the mean and variance, type: motor ships of the largest acceleration, output: 2 acceleration mean and variance diagram.)