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This paper investigates the problem of exponential stabilization for sampled-data Takagi–Sugeno (T–S) fuzzy control systems with packet dropouts. An input delay approach is adopted to model the sample-and-hold behavior with a time-varying delayed control input, and a switched system approach is proposed to model the data-missing phenomenon. On this basis, the sampled-data T–S fuzzy control system with packet dropouts is modeled as a switched T–S fuzzy system with time-varying delay. The objective is to design a sampled-data fuzzy controller to guarantee the exponential stability of the resulting closed-loop system. Based on a new piecewise time-dependent Lyapunov functional, a novel sufficient condition is derived for the existence of exponentially stabilizing sampled-data fuzzy controllers. All the solutions to the problem are formulated in the form of linear matrix inequalities. Finally, two simulation examples are provided to illustrate the effectiveness of the proposed methods. [ABSTRACT FROM PUBLISHER]

A method of fast computation of the mixed potential Green's functions (MPGFs) in spatial domain for cylindrically stratified media has been developed. Based on the convergence behavior of the MPGFs in spectral domain, the discrete complex image method (DCIM) and the extrapolation technique are employed to perform the inverse Fourier transform, which is different from that of planarly stratified media. In order to evaluate the summation of cylindrical eigenmode from order of negative infinity to order of positive infinity, the Green's functions in spectral domain are rearranged so that acceleration technique can be well applied to speed up the convergence of summation process. For the integral along the deformed Sommerfeld integral path with respect to kz, DCIM is used to speed up the computation. After the quasistatic components are completely subtracted from the spectral domain Green's functions, the inverse transform of the remaining parts has an approximated analytical form. The proposed method can be used to accurately and efficiently calculate the spatial domain MPGFs, which are useful for characterizing conformal patch structures mounted on cylindrically stratified media. [ABSTRACT FROM AUTHOR]