网络病毒与谣言传播问题研究，宋玉蓉.ppt

Super-spreaders in SARS One-hundred-forty-four of the 206 SARS patients diagnosed in Singapore were traced to a chain of five individuals that included four super-spreaders. The most important of these was Patient Zero, the physician from Guangdong Province in China, who brought the disease to the Metropole Hotel.  Visual illustration of the difference between an exponential and a scale-free network. Red, the five nodes with the highest number of links; green, their first neighbours. Although in the exponential network only 27% of the nodes are reached by the five most connected nodes, in the scale-free network more than 60% are reached, demonstrating the importance of the connected nodes in the scale-free network Both networks contain 130 nodes and 215 links k=3.3 The exponential network is homogeneous: The scale-free network is inhomogeneous connected. the BA scale-free networks are very robust against random removal of nodes: comparing to the ER randomgraph network, the size S of the largest sub-network in a scale-free network decreases to zero slowly and for a much larger fraction f of the removed nodes; yet its average path length grows also much slower. Fig. Robustness and fragility of ER random-graph and BA scale-free networks：[20]:(a) and (c): ER random-graph networks; (b) and (d): BA scale-free networks; squares—random removal of nodes; circles—intentional removal of nodes [20]Albert R, Jeong H, Barabasi A L 2000 Nature 406 378 Cheng S M, Karyotis V, Chen P Y, et al. Diffusion Models for Information Dissemination Dynamics in Wireless Complex Communication Networks[J]. Journal of Complex Systems, 2013, 2013 Company Logo 相互依存的网络 Buldyrev, S. V., et al. (2010). Catastrophic cascade of failures in interdependent networks. Nature 464(7291): 1025-1028. 网络观点下的病毒免疫控制策略 随机免疫 目标免疫 网络观点下的病毒免疫控制策略 熟人免疫 网络观点下的病毒免疫控制策略 你的思考？ 小结 复杂网络是二十一世纪科学研究的思想和理念，它启发我们用什么观点理解这个世界：整个世界以及组成世界的任何细部都是由网络及其变化形成的。 复杂网络也是研究复杂系统的一种技术和方法，它关注系统中个体相互作用的拓扑结构，是理解复杂系统性质和功能的基本方法。 赫拉利说：某次偶然