Research On Brittleness Management Of Complex Urban Traffic Network System

Many complex systems are interacting subsystems, when the subsystem is abstracted into a node, the interaction between the subsystems is abstracted into a node edge, then the complex system can be abstracted into a complex network. Complex networks is a complex system of highly abstract, there are a lot of complex networks in the real world, such as social networks (friendship networks, scientific collaboration networks, etc.), traffic networks (urban public transport networks, air networks, etc.), technology networks (Internet, World Wide Web, etc.), biological networks (neural networks, the food chain networks and metabolic networks), economic networks.As a typical complex network,urban traffic network system has an important impact on the reliability of the connectivity of urban transport. In real life,Urban traffic network system is not only attacked by rain, snow and other natural disasters such as wind damage, but also may be subject to malicious attacks and human impact of traffic congestion. And local transport network which will lead to failure will increase the burden on other parts. The entire transport network will be greatly damaged in this manner, and the failure will transfer to the entire network, leading to more damage, resulting in network capacity and efficiency of transport was significantly reduced. Urban public transport network is an inportant part of urban traffic network, its degree distribution are subject to power-law distribution, with the nature of small-world network, but also belong to BA scale-free network, scale-free networks. Because of the uneven distribution of degree in the BA scale-free network, the urban transit network demonstrate a robustness against random failures and a vulnerability of deliberate attacks.The thesis mainly research on brittleness of complex urban public transport network system.Firstly,we analysis the brittleness of complex urban public transport network system. As a typical BA scale-free network, the urban transit network demonstrate a vulnerability of deliberate attacks.Then indentified two evaluation which are The largest relative size of the connected subgraph and the network efficiency on the research. It can directly reflect the attack and destruction in the Unicom network reliability before and after the change through the change of the largest relative size of the connected subgraph and the network efficiency.The thesis then analysis the complex urban public transport network model.Take Qingdao City transit network for example.Through the creation of complex network model of urban public transport, we analysis of the complex characteristics of transit network in Qingdao and use of the powerful spatial analysis ArcEngine platform capability in the thesis, analysising of the the reliability of the changes of the transit network connectivity in the deliberate attack mode. At last find the key nodes of the entire transit network by comparing the overall efficiency of the network and the largest connected subgraph of the relative size of the changes.At last through the optimization and protection of these bus stops, make sure the urban public transport network healthy and orderly.