A Study On Methods To Enhance The Reliability Of Urban Transit Service

The priority development of public transportation has been a common view of the whole society with the background of intense supplying of land using, the pressure of congestion management and emission reduction. Urban transit service is a kind of public service with quality attributes to judge in which service reliability is an important one. Enhancing the service reliability can help to attract more passenger to travel in public transport which is environmental friendly. This paper explores the meaning and evaluation index of service reliability. Methods are proposed to enhance the service reliability through analyzing the inner and external influence factors.Considering the passenger demand fluctuation and the vehicle running time randomness, as well as the relationship between the transit service frequency and the transit service reliability, a model for determining optimal bus route service frequency is developed. In this model, the expectation of passengers waiting for buses and the efficiency of running vehicles are aimed to achieve combined optimization. Monte-Carlo method is used to simulate the service process of urban bus route and the optimal service frequency of this example route is calculated given the route parameters. The numerical example shows that this model can be used to determine the departure gap of a bus route.To enhancing the service reliability of fixed vehicle supply, this paper propose a new method of coordinating buses which abandons the idea of a schedule and even any a priori target headway. Under our scheme headways are dynamically self-equalizing and the natural headway of the system tends to emerge spontaneously. It is examined using Markov process theory and simulation in Matlab.