minimum visibility

The authors put forward a new method calculating service level of network in average speed of network,and profoundly discussed principles,methods,two kinds of incorrect tendencies and psychological control factors of tripers determining minimum acceptable service level of network in which city planners and administrators of city develepment are interested most.

分析了市区路网物理、运行、管理特性，提出了用网络平均速度来确定路网服务水平的一种新方法，并对交通规划师和城市发展管理者最感兴趣的城市路网最低可接受服务水平、确定原则、方法、注意问题和出行者心理控制因素进行了较深入的探讨。