Combinational Scheduling Of Skip-stop Bus Considering Bus Emissions

There are quantities of local bus routes in urban areas and each of them serves plenty of intermediate bus stops. Moreover, most of the routes provide an all-stop service, which increases bus emissions, as well as bus travel time, in-vehicle time of long-distance passengers, and waiting time of passengers at the crowed stops. As the auxiliary scheduling of all-stop services, skip-stop services play an important role in reducing bus emissions and the travel time of buses and some passengers. Therefore, it is necessary to conduct a study on the combinational scheduling model based on the skip-stop services to develop scheduling schemes. A reasonable combinational scheduling scheme is important for the reduction of bus emissions, operational costs, and passenger costs.A great many studies on the combinational scheduling model based on skip-stop service have been conducted and most of them foucs on the optimization of passenger costs and operational costs. However, the optimization goal of bus emissions is ignored in those studies. Therefore, a combinational scheduling model based on skip-stop services is proposed to optimize passenger costs, operational costs, as well as bus emissions. In the proposed model, the variation of passenger volume is considered after the skip-stop service is provided. The forbearing stratified sequencing method and genetic algorithm are developed to solve the problem. Then, the system benefits are compared among the combinational scheduling model based on skip-stop service considering bus emissions, the combinational scheduling model besed on skip-stop services without considering bus emissions, and the scheduling model based on all-stop services considering bus emissions. Furthermore, a sensitivity analysis is conducted on different number of buses and passenger demands.First, the method to estimate bus emissions and OD distribution of passengers is proposed. The bus emissions in the all-stop service and the skip-stop service are estimated using the emission measurement method based on Vehicle Specific Power. The OD distribution of passengers in the two bus service schemes is estimated using the Binary Logit model and the Multinomial Logit model which are based on the choice behavior of passengers.Secondly, the combinational scheduling model based on the skip-stop service and the solution are developed. The optimization of total costs of passengers and transit agency and the minimization of bus emissions are regarded as the primary and secondary objectives in the proposed model, respectively. Besides, the constraints of the level of bus service and the number of buses are considered in the model. The forbearing stratified sequencing method and genetic algorithm are further developed to solve the model.Finally, the proposed model is applied for the combinational scheduling scheme design of Route 16 in Beijing. The optimal scheduling scheme which maximizes the system benefits is determined. In addition, the system benefits among the three scheduling models are compared to show the advantages of the combinational scheduling model based on the skip-stop service considering bus emissions. Furthermore, a sensitivity analysis with regard to the number of buses and passenger demands is conducted to demonstrate the stability of the proposed model.