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With the high digitization, informatization, and networking of practical complex systems, the security and reliability issue of systems control in the cyber-physical environment is becoming more and more critical, especially under the background of rampant network attacks nowadays. The security control for time-varying delay systems based on random switching moving defense method in a cyber-physical environment is studied in this paper. First, the security control model of one class of time-varying delay dynamic systems considering the actuator and controller attack problem is presented; second, controller design based on switching strategy for moving defense is studied; and then the security control scheme for time-varying delay systems based on random switching moving defense is presented for dealing with cyber attacks from malicious adversaries. Finally, multiple simulation results are presented to show the effectiveness of the proposed scheme.

This paper is concerned with the problem of extended dissipativity-based state estimation for uncertain discrete-time Markov jump neural networks with finite piecewise homogeneous Markov chain and mixed time delays. The aim of this paper is to present a Markov switching estimator design method, which ensures that the resulting error system is extended stochastically dissipative. A triple-summable term is introduced in the constructed Lyapunov function and the reciprocally convex approach is utilized to bound the forward difference of the triple-summable term. The extended dissipativity criterion is derived in form of linear matrix inequalities. Numerical simulations are conducted to demonstrate the effectiveness of the proposed method.

This paper presents a state of charge (SOC) estimation method based on fractional order sliding mode observer (SMO) for lithium-ion batteries. A fractional order RC equivalent circuit model (FORCECM) is firstly constructed to describe the charging and discharging dynamic characteristics of the battery. Then, based on the differential equations of the FORCECM, fractional order SMOs for SOC, polarization voltage and terminal voltage estimation are designed. After that, convergence of the proposed observers is analyzed by Lyapunov’s stability theory method. The framework of the designed observer system is simple and easy to implement. The SMOs can overcome the uncertainties of parameters, modeling and measurement errors, and present good robustness. Simulation results show that the presented estimation method is effective, and the designed observers have good performance.

This paper investigates the problem of finite-time boundedness filtering for discrete-time Markovian jump system subject partly unknown transition probabilities. By using the multiple Lyapunov function approach, a novel sufficient condition for finite-time bounded of H∞ filtering is derived and the system trajectory stays within a prescribed bound during a specified time interval. Finally, an example is provided to illustrate the usefulness and effectiveness of the proposed method.

In this paper, a stochastic predator-prey system with Holling II functional response is studied. First, we show that there is a unique positive solution to the system for any given positive initial value. Then, stochastically bounded of the positive solution to the stochastic system is derived. Moreover, sufficient conditions for global asymptotic stability are also established. In the end, some simulation figures are carried out to support the analytical findings., {"references":["","A. Lotka, Elements of Physical Biology, Baltimore, USA: Williams\nand Wilkins, 1925.","V. Volterra, Variazioni e fluttuazioni del numero dindividui in specie\ndanimali conviventi, Mem. Acad. Lincei, 1926, 2, 31-113.","Y. Li and H. Gao, Existence, uniqueness and global asymptotic stability\nof positive solutions of a predator-prey system with Holling II functional\nresponse with random perturbation, Nonlinear Anal, 2008, 68, 1694-\n1705.","M. Liu and K. Wang, Global stability of a nonlinear stochastic predatorprey\nsystem with Beddington-DeAngelis functional response, Commun.\nNonlinear Sci. Numer. Simulat, 2011, 16, 1114-1121.","C. Ji, D. Q. Jiang and X. Li, Qualitative analysis of a stochastic ratiodependent\npredator-prey system, Journal of Computational and Applied\nMathematics, 2011, 235, 1326-1341.","J. Lv and K. Wang, Asymptotic properties of a stochastic predator-prey\nsystem with Holling II functional response, Commun Nonlinear Sci\nNumer Simulat, 2011, 16, 4037-4048.","D. Q. Jiang, N. Shi and X. Li, Global stability and stochastic permanence\nof a non-autonomous logistic equation with random perturbation, J.\nMath. Anal. Appl, 2008, 340, 588-597.","C. Ji, D. Q. Jiang and N. Jiang, Analysis of a predator-prey model\nwith modified Leslie-Gower and Holling-type II schemes with stochastic\nperturbation, J Math Anal Appl, 2009, 359, 482-498.","X. Mao, Stochastic differential equations and applications, Chichester,\nEngland: Horwood Publishing, 1997.\n[10] Q. Luo and X. Mao, Stochastic population dynamics under regime\nswitching, J Math Anal Appl, 2007, 334, 69-84.\n[11] X. Li and X. Mao, Population dynamical behavior of non-autonomous\nLotka-Volterra competitive system with random perturbation, Discrete\nContin Dyn Syst, 2009, 24, 523-545.\n[12] D. Higham, An algorithmic introduction to numerical simulation of\nstochastic differential equations, SIAM Rev, 2001, 43, 525-546."]}

A fault detection algorithm for turbopump based on lifting wavelet and LMS is proposed in this paper, to deal with the health monitoring of turbopump which is of high failure rate. Lifting wavelet transform is used for signal decomposition and single-scale reconstruction. And fault feature is extracted from the weighted average energy of approximation signals and detail signals, and its sequence is filtered by LMS (Least mean square error adaptive algorithm). After calculating the ratio between the fault feature point and the mean value of its neighboring local feature points, the failure of turbopump can be identified according to the change of the ratio. This algorithm is verified by using simulation vibration acceleration signals of a certain type of turbopump to simulate the process of hot commissioning. The results indicate that the algorithm presented in this paper can effectively detect the failure of turbopump with good performance of real-time and accuracy.