说明：  DIRECT是一种采样策略，主要运用于高维、黑箱等问题。此中采样策略可以很好的兼顾全局最优和局部最优，是一种比较好的采样方法
(Direct is a sampling strategy, which is mainly used in high dimension and black box problems. The sampling strategy can take into account the global optimal and local optimal, which is a better sampling method)