Research On The Bus Operation Evaluation And Timetable Optimization Based On Hybrid Vehicle Size Mode

As the acceleration of the urbanization in China, more and more people pour into the city, which brings great pressure to the urban transportation system. Nowadays, the serious traffic jam is becoming familiar to the people living in the megac ities in China like Beijing, Shanghai, increasing the travel cost for everyone. And what is widely reported, the air pollution is related to the jammed traffic too. The strategy of public transport priority is accepted by many researchers and government officials as the best way to solve the urban transportation problem. The general office of the State Council has emphasized the importance of the public transportation for series years. As the main part of the urban public transportation, the bus system is the key to promote the development of the public transportation. The optimization of the timetable is effective to improve the efficiency of the bus system.On the basis of the analysis of the problem existing in the bus system, the research evaluates the effic iency of the bus operation at different periods using Stochastic Frontier Analys is approach(SFA) at the first stage. Based on the evaluation results, a new timetable optimization approach adopting hybrid vehic le s ize mode is proposed and the rationality is analyzed also in the research.At the first stage, which is the effic iency evaluation of the bus at different periods, the definition of the effic iency is discussed, and frontier models is introduced, includ ing parameter models and non-parameter models. The advantages and disadvantages of SFA is interpreted, and Cobb-Douglas production function is used to estimate the frontier. The first step of efficiency evaluation is to divide the bus operation into different periods. Inputs index and outputs index at different periods are calculated, and based on the evaluation results, we can obtain some constructive advices from the evaluation, which is important for the timetable optimization in the second stage.At the stage of timetab le optimization based on the hybrid vehicle types sizes, the operation parameter is defined firstly, and the cost of the different vehic le size mode is taken into consideration. Combined with the classical timetab le models, the objective function of the mode is to minimize the total cost, including the waiting time cost, in-vehic le time cost and operating cost, and unlike the traditional timetable optimization model, the decis ion variab le is not the only the schedule interval, but also include the vehic le type size, which can be more adaptive to the fluctuation of the passengers.The main innovations of the research are as follows: the subjective of the operation evaluation is segregated into time periods, which will reflect the problem in the operation more directly; secondly, the hybrid vehic le size mode is proposed and it will be more flexib le to tackle the passenger demand fluctuation.Finally, the data of Bus Route 55 is used and the evaluation results reveal the effic iency at different periods is significantly different, which is related to the average number passengers at every vehic le. The timetable optimization model also demonstrates the hybrid vehicle type size mode is superior than the conventional vehic le type size mode and small vehicle size mode, and it is fit to the real world operation.