Optimization Model for Multi-Vehicle-Type Structure in Urban Bus Systems

Nowadays, bus lines commonly share terminals, especially in urban areas, because an independent operation of each line would cause a large waste of resources. In addition, if lines share terminal all lines can be monitored by unified management, while the vehicles of different sizes can complement each other. Although the dispatcher generally sets up fixed departure intervals for bus lines, there are differences between bus lines in terms of operating time distribution and line volume. Thus, a new optimization model for multi-vehicle-type structure in urban bus system is proposed in this paper. The optimization was conducted according to two main characteristics of bus systems, bus company expense and bus service quality. The optimization model was designed based on minimal possible expense and maximal possible quality. At the same time, we proposed a Markov method based on alternative relations to solve the model. The proposed model was verified by real urban bus system. Moreover, the simulations in MATLAB software environment have proven a high efficiency and applicability of the proposed method.