滑板运动和冲浪运动中的动力学模型的特性

研究了滑板运动和冲浪运动中动力学模型的特性，即在光滑四滚线上和粉植圆滚线上的滑板，在竖直平面内，同一水平线上经过一个最低点的任意两点所有光滑连接线中；物体无初速度滑动时，所需时间最短的曲线是圆滚线（最速降线）这一特性对目前国际上滑板运动和冲浪运动具有指导性的意义．

The Properties of Dynamic Model in the sliding or surfing Sports

The properties of dynamic model for the motions of slide or surf - riding have beeninvestigated. The conclusions to come from the studies display a very valuable character, i. e. whenthe slide to have initial velocity to be zero within a vertical plane moves from a point to anotherpoint to be on the same level as prepoint via a lowert point, the time for the motion of the slide toslide along a hypocycloid (brachistochrone) is the shortest(no matter what there is friction on thehypocycloid or not), which gives an instruction in the motions of slide or surf- riding all over theworld.