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Abstract: Recently, cities have become larger and larger, and more and more people are living in large cities. This phenomenon has caused serious traffic congestion which is very detrimental to the development of large cities. In this context, the subway has become the most effective solution for relieving traffic congestion and subways have been constructed in many cities, so the reliability and robustness of subways should be guaranteed. In this paper, Shanghai subway network, in China, will be analyzed and investigated; the topological characteristics and functional properties can be studied in order to assess the reliability and robustness. The topological characteristics can be measured using several parameters; meanwhile the fraction of removed nodes of Shanghai subway network is discussed and compared against that for a random network, and the critical threshold of this fraction is obtained. Two novel parameters called the functionality loss and connectivity of subway lines are proposed for measuring the transport functionality and the connectivity of subway lines. Subway lines 4 and 7 are selected as examples for evaluating the connectivity of lines subjected to different attack protocols. This study indicates that the subway network is robust against random attacks but fragile for malicious attacks, and the highest betweenness node-based attacks can cause the most serious damage to subway networks among the different attack protocols. [Copyright &y& Elsevier]

Abstract: A generalized complex dynamical networks model with neutral-type coupling delay is proposed, which is an extension for the systems without time delay and with the retarded delay. By some transformation, the synchronization problem of the complex networks is transferred equally into the asymptotical stability problem of a group of uncorrelated neutral delay functional differential equations. Furthermore, the less conservative sufficient conditions for both delay-independent and delay-dependent asymptotical synchronization stability criteria are derived in the form of linear matrix inequalities based on the free weighting matrix strategy. Numerical examples are given to illustrate the theoretical results. [Copyright &y& Elsevier]

Abstract: Urban rail transit networks (URTNs) have experienced rapid development and have been receiving much attention recently. In this paper, we comprehensively analyze the topological characteristics of urban rail transit networks, and we find that the average degrees of nodes of urban rail transit networks lie in the interval [2, 2.45], most of the average shortest path lengths between pairs of nodes belong to the interval [10, 16] and the average betweenness of nodes and edges linearly increase with the increase of the number of stations. Moreover, the cumulative probability distributions of the degree and shortest path length can be fitted by exponential distribution and Gauss distribution, respectively. The network failures of the urban rail transit networks are discussed and we also discover that the highest betweenness node-based attack is the most effective method to destroy the network. [Copyright &y& Elsevier]

Abstract: This paper investigates robust and fast consensus of multi-agent systems subject to external attacks. The strategy of connecting neighbor set is proposed to recover the connectivity of the resulting interconnected network, to improve the robustness against next external attacks, and to guarantee the fast consensus of the resulting multi-agent systems. Two strategies are provided to optimize the robustness against next external attacks and the convergence speed of achieving consensus, respectively. Meanwhile it turns out that there exists a trade-off between improving the robustness against next external attacks and enhancing the convergence speed of achieving consensus. Several simulations are provided to demonstrate the effectiveness of the theoretical results. [Copyright &y& Elsevier]

Abstract: We study the effects of mobility on the evolution of cooperation among mobile players, which imitate collective motion of biological flocks and interact with neighbors within a prescribed radius . Adopting the the prisoner’s dilemma game and the snowdrift game as metaphors, we find that cooperation can be maintained and even enhanced for low velocities and small payoff parameters, when compared with the case that all agents do not move. But such enhancement of cooperation is largely determined by the value of , and for modest values of , there is an optimal value of velocity to induce the maximum cooperation level. Besides, we find that intermediate values of or initial population densities are most favorable for cooperation, when the velocity is fixed. Depending on the payoff parameters, the system can reach an absorbing state of cooperation when the snowdrift game is played. Our findings may help understanding the relations between individual mobility and cooperative behavior in social systems. [Copyright &y& Elsevier]

Abstract: We investigate an evolutionary prisoner’s dilemma game among self-driven agents, where collective motion of biological flocks is imitated through averaging directions of neighbors. Depending on the temptation to defect and the velocity at which agents move, we find that cooperation can not only be maintained in such a system but there exists an optimal size of interaction neighborhood, which can induce the maximum cooperation level. When compared with the case that all agents do not move, cooperation can even be enhanced by the mobility of individuals, provided that the velocity and the size of neighborhood are not too large. Besides, we find that the system exhibits aggregation behavior, and cooperators may coexist with defectors at equilibrium. [ABSTRACT FROM AUTHOR]