Analysis Of Cascading Failure Behavior And Study On Structural Controllability Of Complex Networks

With the advent of the information age,the introduction of complex networks can provide theoretical basis and methods to the study on structural characteristics and dynamic behaviors of complex systems.In order to deeply understand the role of degree distribution and in particular degree heterogeneity,the structural vulnerability of interdependent systems has been investigated and the research results can help to deepen the understanding of structural complexity of complex real-world systems.Through extensive numerical simulations,the effects of Local-World on structural controllability of complex networks have been examined,which can shed some light on the structural role on network controllability of complex systems.After the detailed introduction of the realization of Fitness model,the important structure and dynamic features of scale-free networks have been analyzed with emphasis on the impact of power exponent γ on the network performance.The research results can help to explore and analyze the structural complexity and typical dynamic behaviors of scale-free networks.The main content and innovative results of this thesis are summarized as follows:1.Analysis of attack-induced cascading failure behaviors on complex interdependent networks.In order to deeply understand the role of degree distribution and in particular degree heterogeneity,we construct an interdependent system model which consists of two networks whose extent of degree heterogeneity can be controlled simultaneously by a tuning parameter.Meanwhile,a new quantity,which can better measure the performance of interdependent networks after attack,is proposed.Numerical simulation results demonstrate that degree heterogeneity can significantly increase the vulnerability of both single and interdependent networks.Moreover,it is found that interdependent links between two networks make the entire system much more fragile to attacks.Enhancing coupling strength between networks can greatly increase the fragility of both networks against targeted attacks,which is most evident under the case of max-max assortative coupling.Current results can help to deepen the understanding of structural complexity of complex real-world systems.2.Study on the structure controllability of Local-World networks.Controlling complex networks is of vital importance in science and engineering.Meanwhile,Local-World effect is an important ingredient which should be taken into consideration in the complete description of real-world complex systems.Structural controllability of a class of Local-World networks is investigated.Through extensive numerical simulations,firstly,effects of local world size M and network size N on structural controllability are examined.For Local-World networks with sparse topological configuration,compared to network size,Local-World size can induce stronger influence on controllability,however,for dense networks,controllability is greatly affected by network size and Local-World effect can be neglected.Secondly,relationships between controllability and topological properties are analyzed.3.Modelling and Analysis of scale-free network with variable power-law exponents base on Fitness model.The large-scale complex systems whose node degrees obey power-law distribution are called scale-free networks.The Fitness model is one of the typical models which is used to generate scale-free networks with variable power-law exponent γ.After introducing the detailed realization of Fitness model,the important structure and dynamic features of scalefree networks,including the degree distribution,resistance to attack ability,synchronization performance and structural controllability,are analyzed with emphasis on the impact of power exponent γ on the network performance.The research results can help to explore and analyze the structural complexity and typical dynamic behaviors of scale-free networks.