Research On Traffic Network Node Important Degree Measure And Its Application

The research of the important degree of traffic network nodes have very strong practical significance and application value, most previous studies focused on strengthening the protection after identifying the key node in the network so as to insure the transportation network running much more smoothly under the condition of putting the same resources into the transportation network, when major natural disasters or terrorist attacks occur, it will also help the main function of the transportation network recover rapidly when the recover start from the key nodes. This paper innovates the operational way of the theory of node important degree on the basis of the feature of actual traffic network, then expands its use to evaluate the stand or fall of the traffic network, helps to site for large engineering projects or to solve practical problems in relative areas, greatly developed its use value, and provides a new perspective and tools for experts and scholars in the field of traffic.Due to traffic network is a typical complex network, and it is a double complex network composed by the road network and the travel network, so at first, this paper introduced the relevant theories of complex networks and the research method of the node important degree, systematically elaborated the related knowledge of the road network and travel network, and dialectically analyzed the relationship between them, namely the structure of road network structure will affect the residents travel path choice, and residents’ travel will feedback influence the layout of the road network, they affect each other, promote each other and develop to a more harmonious form.Then reviewed two traditional traffic network node important degree evaluation model, and analyzed the advantages and disadvantages of them. Learnt from the two models and combined with the actual characteristics of transportation network, I try to use the system science analysis method of complex network, namely that to evaluate traffic network node important degree by the change of the total time spent in traffic network after deleting a traffic network node, and then developed a transportation network total time cost evaluation model, then the algorithm was presented and applied to the calculus of the instance.Finally, proposed the concept of the equilibrium level of the transportation network node importance degree based on the transport network node important degree theory. A good transportation network should not have too important nodes that loading excessive traffic likely to cause congestion and have very few too unimportant nodes that the transportation resources can’t adequately perform its function and cause the waste of resources, but transportation network node importance degree shows a roughly equilibrium state. Then make it as a standard, give examples to evaluate the performance of the transportation network, and provide a theoretical basis for the site selection of large engineering projects.