基于信息熵的城市道路可变信息板布点方法

Location Optimization of Urban Variable Message Sign Based on Amount of Information

针对城市道路环境下可变信息板单点选址与设计问题,对交通标志视认过程进行了分析,从可变信息板视认时间与布设环境两个方面对现有布设方法进行了改进.通过引入可变信息板信息量-视认时间模型,建立了城市环境下可变信息板前置距离模型和最小字体模型.该模型可以确保驾驶员有充分的时间接受可变信息板发布的诱导信息,并在接受信息后有充分的反应距离.此外,还给出建成可变信息板的评价方法和可变信息板前置距离与字体高度的推荐值.

Variable message sign(VMS), as an infrastructure of the urban traffic guidance system, is a main platform to release guidance information. Improper installation of VMS is incapable of information releasing, which has a negative effect on the performance of the urban traffic guidance system and traffic safety. Aiming at VMS design and location problem with urban traffic environment, the process of reading traffic sign was analyzed. With the consideration of VMS reading time and city traffic environment, the VMS installation model was built for calculating the VMS frontal distance and the height of characters in VMS. The amount of information model was constructed for evaluating the complexity of VMS and its reading time. In order to ensure that the driver has enough distance to react after accepting the information from the VMS, the queue length and no change lanes zone were also considered in the VMS installation model. In addition, the evaluation method for existing VMS and the recommended frontal distance and the height of characters were given.