Research On Non-parametric Network Entropy Computing Method For Traffic Network Equilibrium

In recent years,the increasing traffic congestion not only reduces people's travel efficiency,but also greatly increases people's travel risk.The unbalanced distribution of traffic flow is one of the most important factors leading to traffic congestion.In reality,when the traffic of some roads is too heavy while traffic of other roads is too small,the traffic flow of the whole road network can maintain normal value but the distribution of traffic flow will be greatly unbalanced,which seriously affects the overall operation efficiency of the traffic network.In the existing research,there is a lack of macro analysis of traffic network equilibrium,and network entropy has a wide range of applications as a physical quantity that describes the overall equilibrium of the system.Non-parametric network entropy is a class of network entropy,it reflects the different characteristics of the network by different definition of information functions.In order to evaluate the degree of traffic network equilibrium,this paper defines the information function based on the shortest path,and quantitatively reflects the equilibrium difference of traffic network by the value of entropy.The main research content of this paper is as follows:(1)According to the calculation formula of non-parametric network entropy,a new information function is proposed and the non-parametric network entropy based on the shortest path is defined.By calculating the entropy value of the traffic network,the spatial equilibrium of the traffic network is evaluated.(2)The traffic network is modeled and abstracted into a complex network model.The matrix eigenvalue of traffic network is calculated and clustered.The optimal clustering number is taken as a parameter of non-parametric network entropy,which establish the foundation for follow-up study.(3)Different molecular matrices are extracted from the traffic network and the molecular matrix based on the performance of the road network is defined.Entropy is used as descriptor to quantitatively calculate the spatial equilibrium of the traffic network.The sensitivity indices of different molecular matrices are compared,which reflects the discrimination ability of traffic network equilibrium.(4)Based on the real traffic network data,this paper generates a variety of complex network models and weight data for comparative analysis.The experimental results show that the non-parametric network entropy calculation method based on the shortest path in this paper can reflect the equilibrium of traffic networks.The higher the entropy value,the more equilibrium of traffic flow.Compared with other molecular matrices,the efficiency matrix has the highest discrimination power when distinguishing the equilibrium of traffic networks.