Weight Optimization Of Comprehensive Evaluation Index For Urban Network Operation State

How to accurately grasp the traffic operation state of road network in order to develop efficient traffic management control scheme and reasonable travel scheme is the key to improve the operation efficiency of road network,and the evaluation of traffic operation state of urban road network is of great significance.The weights of evaluation indexes set by the current evaluation model of road network operation state are often fixed values,which only conform to the traffic operation conditions under the initial conditions.With the change of time,the initial index weights can not adapt to the changes of road network traffic conditions.Therefore,this paper proposes a dynamic evaluation method of urban road network based on index weight optimization.The main contents of this paper include the following aspect:Firstly,this paper summarizes the current research progress of urban road network operation state evaluation index,weighting method,evaluation method and index weight optimization method at home and abroad.By comparison,the advantages of the dynamic evaluation method of urban road network based on index weight optimization are obtained,which lays the foundation for the follow-up research of this paper.Secondly,the model framework of urban road network dynamic evaluation method based on index weight optimization is determined.Because the evaluation method of road network in this paper is based on the evaluation of point,line and surface,the traffic state evaluation indexes are selected at intersections and road sections respectively,and each evaluation index is standardized to a value between 0-100 according to the standardized formula provided.It is determined that the evaluation method used in this paper is the weighted scoring method.In the optimization period,the objective is to minimize the difference between the evaluation results and the experts’ evaluation results.The weights of each index are greater than 0 and less than 1,and the sum of all indexes is 1.Then,the model is solved by genetic algorithm and particle swarm optimization algorithm,and the optimized index weights are brought into the road network evaluation model to get the optimized urban road network Road network operation status score.Finally,in Lianyungang urban area,two suitable road networks are selected as the research objects of this paper,which are road network a and road network b respectively.The dynamic evaluation method of urban road network based on index weight optimization proposed in this paper is verified by an example.VISSIM software is used to simulate the urban road network,obtain the traffic parameters of each optimization period,and calculate the evaluation index.Taking the road network expert scoring value as the benchmark value,the weights of the evaluation indexes optimized based on genetic algorithm and particle swarm optimization algorithm are determined respectively,and the evaluation results of the road network operation state after the index optimization are calculated.The results show that the evaluation results of road network operation state after weight optimization are real-time and more in line with the actual situation.In view of the lack of real-time performance of the current evaluation method of urban road network operation status,this paper proposes a dynamic evaluation method of road network based on index weight optimization,which improves the adaptability of the evaluation model to the traffic operation status,and has a very important significance to grasp the road network operation status timely and accurately.