Study On Optimization Of Single Route Bus Departure Schedule Considering Congest

At present,China’s urbanization process is still accelerating,and the contradiction between the increasing number of cars and the limited traffic capacity of roads is still prominent.As an important part of urban transportation system,urban public transportation has the advantages of large capacity,travel economy and high safety factor,and has become a priority mode of transportation development in all major cities.Urbanization process is still accelerating,and the contradiction between the increasing number of cars and the limited traffic capacity of roads is still prominent.As an important part of urban transportation system,urban public transportation has the advantages of large capacity,travel economy and high safety factor,and has become a priority mode of transportation development in all major cities.Regular bus is an irreplaceable part in the public transport system,the current public transport operators in the regular bus dispatching and departure schedule often ignore the car crowded conditions,so it’s easy to have a car of overcrowding,and lower the car’s comfort,so in this paper,considering the car crowded conditions,the single wire bus service frequency optimization model was constructed,and then use the comparative analysis of the results of example is optimized and the compilation of departure schedule,finally uses the deficit function calculating minimum size.The main research contents and results of this paper are as follows:(1)The relevant theories of departure schedule preparation were summarized.Considering the problem of bus congestion,the evaluation of bus congestion and cost quantification indexes were analyzed,and the departure frequency optimization model considering bus congestion was built,and the one-dimensional search algorithm was used to solve the problem.(2)Based on the passenger flow data of No.1 bus line in Zhuhai Scenic Area of South Sichuan in Yibin City,the optimal solution was obtained through the optimization model,and the optimization results were compared and analyzed to test the applicability of the optimization model.The results show that:(1)Compared with the present system,the optimized departure frequency of each time period is increased;(2)After optimization,the total cost of the system in each period is reduced by more than 5%,and the total cost of the system in five periods is reduced by 8.53%,which proves the effectiveness of the optimization model.(3)Considering the conditions of vehicle congestion,the total cost of the system after two periods of optimization is reduced by 1.62% and 2.14%,respectively,compared with the current system.The optimization results of the model are sensitive to the changes of two important parameters,which proves that the optimization model has good applicability.(3)Value the departure interval through "integral method" and "clock method";The average departure interval method and the smooth transition method are used to calculate the congestion cost of the adjacent period respectively to compare the two transition methods.Based on the two schemes’ departure schedules,the minimum fleet size can be calculated by deficit function under the condition of considering whether the sending vehicles are out of time.The results show that:(1)For the median value of optimal departure interval,it is better to round up;(2)When dealing with the transition problem of departure interval between two adjacent periods,the smooth transition method is more appropriate;(3)The two schemes developed after optimization of the departure schedule,are alternative schemes,taking into account the interests of both passengers and bus enterprises.