The urban traffic trunk is regarded as a large system , and the subsystems are the intersections in the trunk . then we desipi a two - level coordinated fuzzy control method and use ann to implement the fuzzification , fuzzy inference and defuzzification . the arithmetic homs the strongly self - adapt , self - learning and fault - tolerant function 3 )把城市交通干线作为一个大系统，子系统为干线上的各个交叉口，在此基础上，设计了一种城市交通干线的两级模糊协调控制算法，并用bp神经网络实现控制器的模糊化、模糊推理和清晰化三个部分，系统具有较强的自适应、自学习和容错性。
