Research On The Coordination Of Urban Public Transit Compound Sysytem

In the cities especially metropolises that have activated the rail transit network,the metro lines and the existed bus lines converge,forming an enormous urban public transit compound system.As an important part of urban traffic system,the coordination between the whole exterior city system and urban subway-bus compound network,and between its two interior sub-systems,is becoming the critical issue to promote the rapid development of our cities at this stage.Therefore,according to the exterior and interior connotation,the coordination between urban public transit compound system and some factors,such as the configuration & economy of the city,the urban private car system and the subway & bus sub-systems,is discussed.The four parts of content in this paper are mainly contained as follow:Firstly, the coordination of the rail transit system and bus system with the formation and layout of the whole city is analyzed.Based on three effects as the integration scale effect involving population,land,economy and environment four macro scale factors,the basic morphology effect involving job-housing balance,trip characteristic,network shape analysis and the development trend effect which indicates the after effects on urban staged development caused by the construction of track traffic,the multi-effect measuring method for reasonable scale of urban track traffic network is proposed according to the unique staged conditionality of economy.Then the integration effect evaluation model of rail transit passenger volume based on PSGA(Genetic Algorithm Based on Predatory Search Strategy)and WLS-SVM(Weighted Least Squares Support Vector Machines) is built to forecast the potential passenger volume from each traffic zone.And an optimal routing algorithm for centroids of traffic zones is proposed to search for the optimal urban rail transit conceptual network layout with the maximum passenger volume.Meanwhile,the optimization and adjustment model for achieving the coordination between bus network and the urban system is also improved.Secondly, the coordination of urban public transit compound system with the private car system is discussed.A Nested-logit model which focused on the combined selection problem about commuters' mode choice behavior and departure-time along the corridor is established.And mutual effect mechanism between varied commuter groups and evolution law of commute travel evolutionary game under differential policy guide are studied.Simultaneously,considering the synergic competition of artery traffic which involves private car&routine bus system at peak hours,a service decision model based on the Travelers' choice preference and trip modes utility is proposed to achieve the Travelers'maximal profits.Thirdly, based on complex network theory,an empirical study of the topology characteristics of Chengdu urban subway-bus compound network which involves both subway network and bus transit network is presented with establishing undirected and unweighted networks in Space L&Space P.And the static invulnerability of the compound network under under different attack modes is also tested.Furthermore,taking into account the measures of governmental intervention,the synergic competition strategic decision model evaluating the individual benefits of public transit operators and the improved multi-objective programming model for bus network optimization and adjustment considering the urban rail transit lines are also proposed.Finally, the propagation of network overload and/or congestion,and the cascading failure process under subway emergency is measured with Chengdu urban subway-bus compound network, through the simulation algorithm in the light of the limitation of network capacity.Then incident emergency response project of bus emergency response after urban rail transit emergency interruption is proposed on the basis of the simulation analysis when the existed bus network can't relieve the passengers affected by the sudden interruption effectively.Moreover,the operation schemes of the bus emergency response to the emergent passenger transportation under the condition of the relatively limited sufficient capacity is analyzed.