基于畅通度度量的无尺度网络中关键节点的选取方法

Measure of Node Importance and the Method of Choosing Key Nodes in Scale-Free Network

现实世界中大量存在着的无尺度网络的抗蓄意攻击能力的不足,决定了从无尺度网络中选择关键节点的重要性。网络中节点的重要性程度可用将该节点从网络中删除前后,网络的连通性能的变化进行度量。文章提出了无尺度网络畅通度的概念,从3个不同的角度对无尺度网络的畅通度进行评价,构造出无尺度网络畅通度的综合度量公式,构建了无尺度网络的关键节点的选取模型,并利用分布估计算法对模型进行求解。仿真结果表明,利用分布估计算法得到的结果要好于直接选取度数最大的节点作为关键节点的方法。

The insufficient capacity of scale-free network for resisting the intentional attack is widespread in reality,and thus it is of importance to choos the key nodes from scale-free network. The importance of a node in the network was able to be measured by the change of the network connectivity when the node is removed from the network. Thus,the concept of scale-free network unimpeded degree is proposed. By evaluating unimpeded degree of scale-free network from three aspects,the formula for measuring unimpeded degree is worked out. Model is established to select the key nodes from scale-free network,and then the estimation of distribution algorithm is able to solve it perfectly.It is revealed by the simulation that the estimation of distribution algorithm is better than the method which selects the nodes with maximum degree as the key nodes directly.