Research On Optimization For Flow Routing Of Urban Passenger Hubs

With the rapidly develop of China's economic and the frequently of social interaction, the growth of transport demand is increased quickly. At present, China is in a period of diverse passenger transports with a quickly develop. Based on the improvement and improvement of regional integrated transport network, China has gradually built a number of city comprehensive collections of passenger hub with various transports. Contact a variety of modes of transport as a link, urban passenger transport hub to be provided safely and efficiently to passenger for take down service, and play transit and distribution function when there are a major of passengers. Thus, in the context of network operations, the actual situation of "fast in the middle and slow at both ends" put forward higher requirements on the integration of urban passenger hub operations. In summary, improving the infrastructure network, systematic studying the passenger terminal passenger flow routing design optimization techniques and methods and developing rational and efficient passenger flow routing program will help improving the organization of passenger flow, playing the distribution and transshipment function of passenger hub, and enhancing the efficiency and service quality of integrated transport system.In this paper, we study on urban passenger flow routing, focusing on the hub of passenger flow routing design and optimization of related technologies and methods. The main thesis works as follows:(1) Based on the study of grading standards of hub, the paper explain the basic classification principles, and put forward a classification and grading standard of urban passenger transport hub with evaluations (functional orientation, ability and area). On this basis, explored the relationship between the level and the flow line of hub, analysis the difficulty of flow-line design in the different levels of passenger hub; and studied the relationship between the passenger flow routing design and the layout of the facilities, then point out that architectural space layout, function zoning and traffic to attract the location of the source occurred of hub is the basic of passenger flow routing design in the hub.(2) Based on the analysis of generalized cost factors of passenger flow routing in the hub, the paper divide generalized cost into two parts (section and node). Considering the passengers'psychological perception factors of congestion and service levels, build a section generalized cost function with BPR resistance function; abstract the node as a non-size virtual point with flow, and build a node generalized cost function based on the Webster model. Parameter analysis showed that:with a geometric growth, the value of generalized cost increase when congestion and uphill slope increase. This point out that path generalized cost function not only reflects passenger travel time, but also reflects the impact of psychological factors in the path selection.(3) As the base of design and optimization, the distribution of urban traffic flow model is applied to the study of passenger flow distribution in the hub.Based on the comparative the difference of distribution between passenger flow and traffic flow, analyze that the nature of the passenger distribution is to consider single-path capacity limit of the flow distribution; then based on flow distribution, construct a optimization model of passenger flow, and determine the collection of alternative paths () using K gradually shortest path algorithm, the generalized cost minimization as the optimization goal, passenger traffic allocation by a single path, and then determine the optimal passenger flow routing design. The analysis the uncertainty of overall OD demand single-OD demand in the model shows that:the overall OD demand increases, the total cost of system showing exponential growth, the total cost of the node in the generalized cost increase form16.61%to49.54%; the more single-OD demand changes, the greater increase of total cost with the increase of unit, and the proportion of passengers' cost at the nodes in the network total cost increased significantly, then nodes became the key faction to constraint the efficiency of network and optimize of passenger flow routing.(4) Maximum entropy principle, developed from statistical physics, was applied into the design and optimization process of passenger flow routing in the hub. Under the framework of entropy method of information theory, explain the differences of different flow lines combinations in the same generalized cost, and the phenomenon of entropy in the process of flow design optimization, then introduction the measure entropy of passenger flow routing design optimization; based on the maximum entropy principle, describe the passengers flow line design as a optimization process to maximize the measure entropy. Then, build a t maximum entropy model of passenger flow routing design optimization, and gives the calculation method. Through the uncertainty analysis of OD demand and general cost estimate of the model shows that:because of the uncertainty of the information of factors in the passenger flow routing design optimization process, hub architecture with a high degree of spatial layout of the matching program will have a greater probability to be choose as the optimal design, and the degree of matching is estimated by OD demand and generalized cost.