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People like to communicate with others who have similar opinions in daily life. “Open” individuals are willing to accept peers’ opinions, whereas “conservative” individuals are more closed to others’ opinions. Based on this reality, an opinion dynamic model is proposed with a time-varying trust threshold related to the node degree, which refers to the number of individuals that can be communicated directly. Similar opinions within the trust thresholds at the beginning will eventually form a consensus opinion. Individuals who have common neighbors converge to consensus faster than ones who have no common neighbors. The network size impacts the convergent speed of the opinion cluster and the trust threshold cluster. Individuals in small groups are more stressed than in large ones when they try to insist their opinions. A group with half of the individuals categorized as doubting and the other half categorized as trusting exhibits consistent confidence but experiences difficulty in reaching a consensus: “harmony but difference” may be a criterion for unifying a group.

The traditional surface control method is developed in this paper which is based on the state observer on line and this method is applied in saturated water-steam temperature system. Certain first-order low-pass filters are introduced into the designing process to avoid the occurrence of high-order derivatives of elements in the system which makes it easy to implement in practical applications. The stabilization of this control method is verified. Simulation results show that the dynamic surface control method still ensures an accurate result, even if the loads change in a great and parameters of the controlled plant change significantly.

In this paper, the relations of the scale-free network topology and the moving consensus of multi-agent systems are studied. A synchronization-preferential BA (SPBA) network with the combinatorial preferential attachment is presented for the prestissimo consensus. The effects of the SPBA network on the algebraic connectivity of the topology graph are compared with the standard BA network. The robustness gain to delay is analyzed for variable network topologies with the same size. The characteristics of dramatic increase for the algebraic connectivity and slightly increase for the robustness gain to delay are unfolded in SPBA network. By comparing the convergence time of the different network structures, the consensuses are studied for multiagent systems with and without communication delays.

In this paper, the relations of the network topology and the moving consensus of multi-agent systems are studied. A consensus-prestissimo scale-free network model with the static preferential-consensus attachment is presented on the rewired link of the regular network. The effects of the static preferential-consensus BA network on the algebraic connectivity of the topology graph are compared with the regular network. The robustness gain to delay is analyzed for variable network topology with the same scale. The time to reach the consensus is studied for the dynamic network with and without communication delays. By applying the computer simulations, it is validated that the speed of the convergence of multi-agent systems can be greatly improved in the preferential-consensus BA network model with different configuration.

This paper focuses on the problem of robust decentralized Hinfinity control design for nonlinear interconnected systems with uncertainty. It presents, respectively, a state feedback control design and an output feedback control design, which will stabilize the plant and guarantee an Hinfinity-norm bound constraint on disturbance attenuation for all admissible uncertainties. The interconnection between the robust decentralized Hinfinity control problem and the nonlinear decentralized Hinfinity control for systems without uncertainty is established. Based on this interconnection, the solvable conditions of robust decentralized Hinfinity control is proposed in terms of Hamilton-Jacobi inequality.

This note focuses on linear large scale systems which are subject to both time-varying norm-bounded parameter uncertainty and exogenous disturbance, andaddresses the following robust H ∞ control problem: presenting a necessary and sufficient condition for the existence of a stabilizing decentralized static output feedback controller that makes the closed-loop systems to be quadratically stable and achieves a prescribed level of disturbance attenuation for all admissible parameter uncertainties.

This paper studies the problem of designing robust H ∞ controllers for networked control systems with time delay, packet dropout and time-varying sampling period, which may receive control input during a sampling period. The problem of controller design for aforesaid NCSs is converted into a multi-objective optimization problem in terms of LMIs, and some methods can be used to deal with the multi-objective optimization problem. The simulation results have illustrated the effectiveness of the proposed H ∞ controller design.

Complex networks have established themselves as being particularly suitable and flexible for representing and modeling several complex natural and human-made systems. Inspired by studies on airline and shipping networks, we propose a transport network model that includes geographical attributes along with topological and weight properties. In this model we introduce the theory of cost in micro-economics, regard distance between vertices as a function of cost. In general, a long-range connection cost higher and happen to appear rarely based on this, in our model the topological growth and weight dynamics are both determined by geographical distance cost and capacity of dealing with traffic load in a given vertex. Then we analyze some attributes of this model, the results suggest that the interplay between weight dynamics and spatial constraints is a key ingredient in order to understand the underlying driving factor of real-world weighted networks.

This paper studies the linearization of a similar large-scale nonlinear control system using differential geometry methods. The large-scale nonlinear control system consists of N n-dimensional subsystems which have similar characteristic and relation. It is shown that the large-scale nonlinear control system is linearizable at the neighbour of one point if and only if each subsystem has m output functions and the sum of the corresponding characteristic index is equal to the dimension of the subspace n. and the index matrix has rank m.

A class of end-to-end rate-based TCP-like congestion control algorithms with communication delays is studied. A critical value of the delay to ensure the stability of Internet is presented by analyzing the characteristic equation of the congestion control algorithm. By applying the center manifold theorem and the normal form theory, the dynamics of the algorithm is discussed around the critical delay value. Finally, a numerical simulation is used to verify the theoretical results. These conclusions show the effect of communication delay on the quality of service (QoS) of Internet.

In this paper, the problem of structural control is introduced. The problem is discussed concretely for linear systems with quadratic cost functions, and methods to design the optimal control structure and /spl epsi/-optimal control structure are obtained.