Bus Line Departure Frequency Optimization In The Overlapping Interval Considering Operators

In recent years,with the continuous improvement of urbanization level,the car ownership has gradually exceeded the capacity of urban traffic,resulting in serious traffic congestion.However,due to the advantages of public transport,such as large passenger capacity,less occupation of road resources,light environmental pollution and improving the travel efficiency of residents,it has become the consensus of all countries in the world to give priority to the development of public transport.With the rapid development of public transport in the city,some corresponding problems have emerged,including serious overlapping of sections,unreasonable allocation of line vehicles and so on.In order to solve the above problems,based on the analysis of the characteristics of overlapping sections,this paper constructs a optimization model of bus departure frequency for single operator and a optimization model of bus departure frequency for multi operators according to the number of operators in the overlapping interval.Combined with the passenger flow data of multiple bus lines in Changchun,the effectiveness of the model is verified by the experimental results.The main contents of this paper are as follows:(1)Firstly,the paper analyzes the factors that affect the bus dispatching,including the characteristics of bus line passenger flow,bus enterprise vehicle configuration and technical level,weather,etc.,and then analyzes the bus operation characteristics with overlapping sections,including bus opetation characteristics of single operator and bus operation characteristics of multi operators.These characteristics lay the foundation for the following model.(2)This paper summarizes the optimization problem of bus departure frequency for single operator and establishes the corresponding optimization model of bus departure frequency for single operator.The objective function of the model is to minimize the total travel time of passengers,and the variable is frequency of each line.At the same time,the genetic algorithm for solving the model is introduced.(3)This paper describes the optimization problem of bus departure frequency for multi operators,that is,these lines have overlapping intervals,but different bus companies are responsible for operation.In this case,the bus companies compete with each other.In this paper,the corresponding bi-level programming model is constructed.The upper level model is responsible for the route allocation,the objective function is to minimize the total travel time of passengers,and the objective function of the lower level model is to maximize the profit of each company.The variable is the departure frequency of operating lines,and the corresponding solving steps are designed.(4)This paper carried out corresponding case analysis on the two models previously constructed.The selected bus lines are in Changchun City bus,and the line overlap meets the research requirements of this paper.The experimental results show that the optimization model of bus departure frequency for single operator can reduce the total travel time of passengers by 3.27%.The optimization model of bus departure frequency for multi operators can reduce the total travel time of passengers by 4.89%,and the total waiting time of passengers is reduced by 21.86%.It also showed that the model constructed in this paper can improve the operation efficiency of public transport system,and has great significance for improving the current situation of public transport operation.At the same time,it had certain reference significance for bus line scheduling with overlapping intervals.