本文提出了城市道路网络的动态可分配性概念，以衡量对特定城市道路网络实施动态分配研究的有效性。并将这个概念用于面向动态交通分配的城市道路网络子区划分，考虑了道路网络的动态变化特性，不仅在空间上，也在时间上对道路网络进行了分区研究。该研究可为动态交通分配的建模研究提供合理的背景和对象。

In this paper, a new concept of assignmentability is proposed. The concept is used to assess the efficacy of the dynamic traffic assignment on road networks and also used to be the principle of network time-space division of dynamic traffic assignment. The characteristics of traffic flows are researched not only on space but also on time. At last, the course of dynamic time-space division of traffic network is given. The study provides a rational object for dynamic traffic assignment modeling.