High Performance Start Node Of Edge Ordering For Intrastructure Networks Of BDD Analysis

Nowadays the science and technology change with each passing day and the human development progress are making big strides.At the same time,the production and living actions are increasing the rhythm with the progress of science and technology.With the promotion of global productivity,human communication activities and the systemic engineering are rapidly running in the form of individual network,so the reliability analysis of a variety of networks has important significance for the current human life.Binary decision diagram (BDD) technology is the method that most widely used for network reliability currently.The analysis method of operation process is first to sort the edge variables in the network, then generate the equivalent BDD, finally to the calculation of reliability of BDD.When using the BDD analysis method to calculate the network reliability,the scale of the equivalent BDD has great influence on the process of calculation work efficiency.With bigger scale of BDD the efficiency of calculation is lower,timeliness worse.Using the equivalent BDD withe small scale to calculate the network reliability is very important.We also need to select a start node in generating the equivalent BDD,and the scales of BDD that generated by different edge ordering start nodes could have a huge difference.The smaller scale of the BDD,the better performance of the edge ordering start node.Therefore,the problem of how to select the small scale of BDD to calculate the network reliability is equivalent to how to find the edge ordering start nodes that with high performance to generate the BDD with small scale.In the current network reliability analysis method of BDD,improve the efficiency of the analysis method is very important.This paper has made some research of the high performance edge ordering start nodes that relate to the computational efficiency, the concrete work of this paper mainly include:(1) In different engineering networks,as well as different subsets of K nodes,to sort all the nodes in the network as edge ordering start nodes.Studying about the distribution characteristics of the high performance edge ordering start nodes.Under the condition of different subsets of K node,the high performance edge ordering start nodes always remain the same. Conclusion 1:the high performance edge ordering start node has strong stability.Tagging these nodes in the network partition.the nodes are all fall in one partition.Conclusion 2:the high performance edge ordering start nodes are convergent.(2) Proposed the method of selecting the high performance edge ordering start nodes in the engineering network.First operation is get the network partitions based on the node betweenness,the dividing point and selection rules are specified.Then selected different nodes with compare their performances to determine which network partition contain the high performance edge ordering start nodes.The appropriate betweenness threshold value must be chooses to find the dividing nodes.With many groups of experiment about different engineering networks.the results show that this method is operable and instructive.(3)The way of different ordering strategies traverse all the nodes in the engineering network are different.The BDD scales of the same edge ordering start node may have huge difference.Compared the distribution and stability of high performance edge ordering nodes with different ordering strategies.Summarized the results,the high performance edge ordering start node also has strong stability and the convergent with BFS strategy.Provided certain reference for other available strategies in network reliability analysis.In summary,this paper studied the edge ordering start node in engineering network to find the small size of BDD and improve the computational efficiency of engineering network reliability analysis.We find the distribution and characteristic of the high performance edge ordering start nodes.And on the basis of the study shows the method of selecting the high performance edge ordering start node in engineering netwok.Finally compared the the distribution and characteristic of the high performance edge ordering start nodes between Snooker and BFS strategies,provided certain reference for other available strategies edge ordering research.