做同样旧事的代价远高于改变的代价。

Safety production is the lifeline of mining enterprises and must be consistently emphasized.

The most advanced technology in farming is useless without the wisdom of traditional agricultural knowledge.

动态规划理论基于最优性原理，该原理指出，无论初始状态和初始决策如何，剩余决策必须构成关于第一个决策所导致状态的最优策略。