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This study investigates sliding mode control (SMC) for non-linear networked control systems (NCSs) subject to packet disordering as well as external disturbances. The main objectives of the proposed method are to predict packet disordering and to stabilise the NCSs in case of the unknown packet disordering in the future. Firstly, linearisation of non-linear systems and the technology of adopting the newest control input with a stochastic parameter are employed to model the system as a linear Markovian jumping system. Secondly, with the application of a time series prediction model, the phenomenon of disordering better under the novel measurement is portrayed. Then, robust H∞ SMC is designed by solving the linear matrix inequalities (LMIs). Finally, examples with sampled disordering packets are simulated to illustrate the effectiveness and advantages of the proposed method. [ABSTRACT FROM AUTHOR]

This paper is concerned with transmission rate and control codesign of wireless sensor networked control systems (WSNCS) with time-varying delay. Jointly designing transmission rate and control is an attractive paradigm for WSNCS, since the control performance of WSNCS is highly sensitive to resource-constrained communication networks. The main idea of devised scheme is searching an optimal event-triggered transmission condition on the premise that wireless link capacity constraint is satisfied and stability of systems is guaranteed. The main aim of devised scheme is to greatly optimize control performance of WSNCS. First, two wireless network architectures characterized by multihop and star topology are put forward. Secondly, a model of WSNCS with event-triggered transmission mechanism is constructed. It is followed by stability analysis of WSNCS to obtain the asymptotical stability condition of systems. And then a search algorithm is presented for transmission rate and control codesign. Finally, numerical examples are given to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

We propose an ecoepidemiological prey predator model, where selective harvest effort on predator population is considered. Vaccination and taxation are introduced as control instruments, which are utilized to control number of susceptible prey population and protect predator population from overexploitation, respectively. Conditions which influence nonnegativity and boundedness of solutions are studied. Global stability analysis around disease-free equilibrium is discussed based on robust Bendixson criterion, which is theoretically beneficial to studying coexistence and interaction mechanism of population within harvested ecoepidemiological system. By using Pontryagin's maximum principle, an optimal control strategy is derived to maximize the total discounted net economic revenue to society as well as protect prey population from infectious disease. Numerical simulations are carried out to show the consistency with theoretical analysis. [ABSTRACT FROM AUTHOR]

A novel fault detection technique is proposed to explicitly account for the nonlinear, dynamic, and multimodal problems existed in the practical and complex dynamic processes. Just-in-time (JIT) detection method and k-nearest neighbor (KNN) rule-based statistical process control (SPC) approach are integrated to construct a flexible and adaptive detection scheme for the control process with nonlinear, dynamic, and multimodal cases. Mahalanobis distance, representing the correlation among samples, is used to simplify and update the raw data set, which is the firstmerit in this paper. Based on it, the control limit is computed in terms of both KNNrule and SPC method, such that we can identify whether the current data is normal or not by online approach. Noted that the control limit obtained changes with updating database such that an adaptive fault detection technique that can effectively eliminate the impact of data drift and shift on the performance of detection process is obtained, which is the second merit in this paper. The efficiency of the developed method is demonstrated by the numerical examples and an industrial case. [ABSTRACT FROM AUTHOR]