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In this article, the Tobit Kalman filtering problem is investigated for a class of discrete time‐varying fractional‐order systems in the presence of measurement censoring and stochastic nonlinearities under the Round‐Robin protocol (RRP). The fractional‐order dynamic model is described by the Grunwald–Letnikov difference equation, and the statistical means are utilized to characterize the stochastic nonlinearities that include state‐dependent stochastic disturbances as a special case. The RRP is employed to decide the transmission sequence of sensors so as to alleviate undesirable data collisions. Under the RRP scheduling, only one sensor is permitted to transmit its measurement over the network at each time instant. In light of the renowned orthogonality projection principle, a protocol‐based fractional Tobit Kalman filter is devised with the fractional dynamics and stochastic nonlinearities elaborately addressed. In the pursuit of the filter design, a couple of new terms appear which are in relation to the RRP, fractional dynamics and stochastic nonlinearities arise, and these terms are adequately handled recursively or off‐line. Simulation results are provided to demonstrate the usefulness of the proposed method. [ABSTRACT FROM AUTHOR]

In this article, the maximum‐correntropy‐based Kalman filtering problem is investigated for a class of linear time‐varying systems in the presence of non‐Gaussian noises and randomly occurring uncertainties (ROUs). The random nature of the parameter uncertainties is characterized by a stochastic variable conforming to the Bernoulli distribution. In order to avoid unnecessary data transmission and reduce consumption of limited communication resource, the event‐triggered mechanism (ETM) is introduced in the sensor‐to‐filter channel to decide whether the data should be transmitted or not. A novel performance index is first proposed to reflect the joint effects from the non‐Gaussian noises, the ETM as well as the ROUs. Under the proposed performance index, an event‐based Kalman filter is then constructed whose gain is calculated based on the maximum correntropy criterion. Finally, the effectiveness of the proposed filtering scheme is verified via a practical target tracking example. [ABSTRACT FROM AUTHOR]

This study investigatesthe neural‐network (NN)‐based adaptive decentralised controller design issue for a class of large‐scale non‐linear non‐strict‐feedback interconnected systems with time‐varying asymmetric output constraints and dead‐zone inputs. The existences of the non‐strict‐feedback structure, time‐varying asymmetric output constraints, and dead‐zone inputs lead to the construction of the controller of each subsystem is very difficult. By applying the inherent property of Gaussian functions employed in radical basis function NNs, the non‐strict‐feedback structure is skillfully handled, and the adaptive backstepping method is used to construct the desired controllers of all subsystems. Furthermore, Lyapunov stability analysis shows that all the signals of the closed‐loop system are ultimately bounded, and each subsystem output can converge to an arbitrarily small and predefined time‐varying range with the corresponding constraint is always satisfied by employing a barrier Lyapunov function. Finally, simulation results based on a practical example prove the effectiveness of the proposed design strategy. [ABSTRACT FROM AUTHOR]

In this study, the boundedness and the input‐to‐state stabilisation problems are investigated for a kind of switched delayed differential systems with exogenous disturbances. To reduce the communication burden, an event‐triggered strategy is adopted in the feedback control loop to stabilise the addressed switched delayed differential systems. The notions of boundedness and input‐to‐state practical stability are employed to characterise the control objectives in the presence of exogenous disturbances, switching signals and event‐triggered schemes. Some upper bounds on the system states are obtained and the Zeno phenomenon is shown to be excluded under the proposed event‐triggered scheme. The gain of the feedback controller, the parameters of the event‐triggering function and the switching signals are jointly designed for the underlying delayed differential systems. At last, a numerical example is exploited to given to demonstrate the effectiveness of the authors' developed control scheme. [ABSTRACT FROM AUTHOR]

Abstract: This paper aims to investigate the exponential leader‐following consensus for nonlinear multi‐agent systems with time‐varying communication and input delays by using hybrid control. Based on the Lyapunov functional method, impulsive differential equation theory and matrix analysis, we show that all the followers can achieve leader‐following consensus with the virtual leader exponentially even if only a fraction of followers can obtain the leader's information. Two classes of exponential consensus criteria as well as the convergence rates for the controlled multi‐agent systems are presented under very relaxed interaction topology conditions, i.e., the directed interaction topology among the followers is only required to have p(p>1) disjoint strong components. Finally, two numerical examples are given to validate the proposed theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, the security-guaranteed filtering problem is studied for a class of nonlinear stochastic discrete time-delay systems with randomly occurring sensor saturations (ROSSs) and randomly occurring deception attacks (RODAs). The nonlinearities in systems satisfy the sector-bounded conditions, and the time-varying delays are unknown with given lower and upper bounds. A novel measurement output model is proposed to reflect both the ROSSs and the RODAs. A new definition is put forward on the security level with respect to the noise intensity, the energy bound of the false signals, the energy of the initial system state, and the desired security degree. We aim at designing a filter such that, in the presence of ROSSs and RODAs, the filtering error dynamics achieves the prescribed level of security. By using the stochastic analysis techniques, a sufficient condition is first derived under which the filtering error system is guaranteed to have the desired security level, and then, the filter gain is designed by solving a linear matrix inequality with nonlinear constraints. Finally, a numerical example is provided to demonstrate the feasibility of the proposed filtering scheme. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]