Research On The Model Of Weighted Public Transport Network And Its Applications

There are more and more traffic jams in urban cities nowadays, and developing public transport is the most effective method to solve the problem. Public transport system contains quite a few bus stations and complex bus lines networks, and the contacts among bus stations and bus lines are rather complicated, so it is a typical complex system. In recent years complex networks theory is a hot research field and it is a new angle of view and a new method to study complex systems. The research on the public transport network model and its applications in the method of network science is helpful to observe and understand public transport system broadly, integrally and systematically, and meaningful to the problem finding and solving of present public transport system.The research on the modeling of public transport system in the method of complex networks and empirical analysis based on the model is numerous. However, most of them focused on the static public transport topology network to build unweighted network model, while public transport system composes of road systems, bus lines networks and management systems, so it is spatiotemporally complex. The importance and efficiency of nodes or edges show differently if the passenger flow distribution, the extent of traffic congestion on roads or the geographical distances are different, though in the case of same network topology. There has been some researches on the weighted public transport, yet the definitions of weight value are simple and their physical significances are not clear. To solve the problem, this paper took many factors that have impacts on public transport system into consideration, redefined the weight value, and built the model of weighted public transport network. Then the calculation method of network efficiency, node importance and optimization of public transport network was proposed based on the model of weighted public transport network. Main works and contributions of this paper are as follows:(1) A more precise and comprehensive model of weighted public transport network was built. Firstly this paper built a model of public transport network by its topology in the space L. then Public Transport Efficiency Weighting method(PTEW) was proposed, which redefined the weight value according the definition of public transport efficiency, with considering of bus passenger flow volume and travel time. Modified BPR function is introduced to calculate travel time reflecting traffic congestion. The final model of weighted public transport network model can comprehensively reflect the impact of geographical distance, bus passenger flow distribution and traffic congestion.(2) Based on the model of weighted public transport network, the calculation method of network efficiency was proposed. Based on the calculation of network efficiency, the calculation method of node importance was proposed in the method of node deletion, with consideration of geographical distance, bus passenger flow distribution and traffic congestion. And the experiment results in methods mentioned above were closer to reality.(3) Aiming to achieve maximum network efficiency of public transport network, the optimization scheme based on the model of weighted public transport network was proposed. This scheme can realize the goal of maximum network efficiency and optimal network structure, with geographical distance, bus passenger flow distribution and traffic congestion taken into account.