Secondly, we study the algorithm of the initial collision moment and collision point between balls.

其次，研究了球体与球体间的最初碰撞时刻和碰撞点算法。

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The initial collision age is younger than that of the oceanic crust disappearing on the surface, and older than that of the formation of strong deformation and dynamic metamorphism.

碰撞的初始作用时间，应该在所测年龄最新的洋壳消失以后，在强构造变形与动力变质作用发生之前。

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Initial reports from the emergency services said the first collision saw eight people hurt and five cars involved, but those figures were later updated to 11 casualties and four vehicles.

BBC: M4 south Wales: 11 hurt in four-car crash after hail