The Research Of The Network Communication And Immune Mechanism Based On Friend Relationship

In recent years,the spread of infectious diseases brings harm for all animals,and it also makes people face serious health problem.From early measles,smallpox to SARS,H1N1 flu,H7N9,HIV/AIDS,mad cow disease and Ebola,etc.How to prevent the occurrence of these infectious diseases and control their prevalence,become one of the most urgent problems to be solved.Therefore,understanding the characteristics of transmission of infectious diseases,simulating the process on the basis of the spread of infectious disease,further,and designing effective immunization strategy are important purpose of the research.These also have very important practical significance.With the appearance of the complex network,its theory associates with communication science to study the transmission behavior of infectious diseases,and designs different immunization strategies.These have become an important direction of research on the spread of infectious diseases.Now,more and more scholars commit to studying infectious diseases,constructing many network models close to the real world,establishing different transmission models for different infectious diseases,and designing corresponding immunization strategies.Although the achievement is remarkable,there are still many problems to be studied.Based on current situation and related achievements of the characteristics of infectious diseases and immunization mechanism,the dissertation analyzes transmission behaviors in two typical networks and calculates the corresponding epidemic threshold.In addition,the simulation experiments are carried out.The main work of the dissertation is as follows:(1)The SIRS propagation model is improved on two classical networks,and the most common friend first immunization is proposed.The direct and the indirect neighbor nodes are immune in different proportions,but the indirect neighbor node with the most common friends is first immune.Meanwhile,the propagation situations of three different immunization schemes — random immunization,high-risk immunization and the most common friend first immunization are studied.Moreover,the theoretical analysis and simulated results indicate that the immune effect of the most common friend first immunization is better than random immunization,but is slightly worse than high-risk immunization.However,high-risk immunization still has some limitations.For example,it is difficult to accurately define who is a directneighbor in the life.Therefore,Aiming at the traditional immunization strategies' shortcomings,the most common friend first immunization is effective,and it is nicely consistent with the actual situation.(2)Based on dynamic network,SIRS spreading model is improved.This dynamic network based on the Barabasi–Albert(BA)scale-free network model is constructed,keeping the same total number of edges and adding or deleting edges according to the specific principles.These operations reflect the change of node activity.According to the characteristics of network changing,an immunization based on node activity is proposed.The propagation situations of random immunization,immunization based on node activity and high-risk immunization are simulated.The influence of some parameters on the density of infected individuals is also analyzed in detail.When the number of immune is the same,the results show that the effect of immunization based on node activity is the best.Therefore,immunization based on node activity is effective,and it is more feasible in dynamic network.