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This paper presents a new method for accurately determining all possible steady-state operating points of a switch-mode contactless power transfer (CPT) system. The method is based on a stroboscopic mapping model and accurate calculation of its fixed points corresponding to circuit zero current switching (ZCS) conditions. Four steady-state operating points are identified for, e.g., inductor--capacitor--inductor (LCL)-type CPT system. Voltage and current waveforms and switching periods are determined. Parameter influences on ZCS periods are studied by bifurcation diagrams. Both PSpice simulation and experimental results have verified the proposed method. The results provide new opportunities for a practical CPT system to operate at different soft switching frequencies. The method is very useful for analyzing switch-mode resonant circuits and designing new power flow controllers. Index Terms--Contactless power transfer (CPT), fixed points, stroboscopic map, zero current switching (ZCS).

This note investigates the stabilization problem for a class of linear uncertain networked control systems with random communication time delays. Both sensor-to-controller and controller-to-actuator random network-induced delays are considered. Markov processes are used to model these random-network-induced delays. Based on the Lyapunov Razumikhin method a mode-dependent state feedback controller is proposed to stabilize this class of systems. The existence of such a controller is given in terms of the solvability of bilinear matrix inequalities, which are to be solved by a newly proposed algorithm. A numerical example is used to illustrate the validity of the design methodology. Index Terms--Continuous-time systems, Markov jump systems, networked control systems, network-induced delays.

A new method for the parallel hardware implementation of artificial neural networks (ANNs) using digital techniques is presented. Signals are represented using uniformly weighted single-bit streams. Techniques for generating bit streams from analog or multibit inputs are also presented. This single-bit representation offers significant advantages over multibit representations since they mitigate the fan-in and fan-out issues which are typical to distributed systems. To process these bit streams using ANNs concepts, functional elements which perform summing, scaling, and squashing have been implemented. These elements are modular and have been designed such that they can be easily interconnected. Two new architectures which act as monotonically increasing differentiable nonlinear squashing functions have also been presented. Using these functional elements, a multilayer perceptron (MLP) can be easily constructed. Two examples successfully demonstrate the use of bit streams in the implementation of ANNs. Since every functional element is individually instantiated, the implementation is genuinely parallel. The results clearly show that this bit-stream technique is viable for the hardware implementation of a variety of distributed systems and for ANNs in particular. Index Terms--Artificial neural networks (ANNs), neural network (NN) implementation.

In this note, the problem of stochastic stability for linear systems with jump parameters being semi-Markovian rather than full Markovian is further investigated. In particular, the system under consideration is described by Ito type nonlinear stochastic differential equations with phase type semi-Markovian jump parameters. Stochastic stability conditions are presented. Index Terms--Ito stochastic differential equations, semi-Markovian jump parameters, stochastic stability.

Recursive-least-square (RLS) algorithm is widely used in many areas with real-time implementation using digital signal processors. In this paper, the authors present a pure hardware implementation of a self-tuning regulator (STR) that uses a real-time RLS algorithm as the parameter estimator. The STR contains a controller design circuit and a controller circuit. Due to RLS computation-precision and dynamic-range requirements, the hardware implementation uses a floating-point format. The floating-point processing elements presented in this paper use parameterized design, where the number of exponents and mantissa bits can be changed as the data range and the accuracy of a specific application require. The strategies for overcoming the covariance matrix asymmetrical problem during the hardware computation and the covariance matrix resetting is introduced when the system is poorly exciting are presented. The design was verified with real-time experiments using a new testbed. The experiment results are presented. Index Terms--Digital signal processor (DSP), estimation algorithm, field-programmable gate array (FPGA), floating-point arithmetic, floating-point format, recursive least squares (RLS), self-tuning regulator (STR).

This paper examines the problem of robust static output feedback control of a Takagi-Sugeno fuzzy system. The proposed robust [H.sub.[infinity]] static output feedback controller guarantees the [L.sub.[infinity]] gain of the mapping from the exogenous disturbances to the regulated output to be less than or equal to a prescribed level. The existence of a robust [H.sub.[infinity]] static output feedback control is given in terms of the solvability of bilinear matrix inequalities. An iterative algorithm based on the linear matrix inequality is developed to compute robust [H.sub.[infinity]] static output feedback gains. To reduce the conservatism of the design, the structural information of membership function characteristics is incorporated. A numerical example is used to illustrate the validity of the design methodologies. Index Terms--BMIs, ILMI, Robust [H.sub.[infinity]] control, T-S fuzzy model.

The problem of designing an H infinity filter for a class of nonlinear singularly perturbed systems described by a Takagi-Sugeno (TS) fuzzy model is described. A numerical example is provided to illustrate the design.

This paper considers the problem of designing an H [infinity] fuzzy controller with pole placement constraints for a class of nonlinear singularly perturbed systems. Based on a linear matrix inequality (LMI) approach, we develop an H [infinity] fuzzy controller that guarantees 1) the [L.sup.2]-gain of the mapping from the exogenous input noise to the regulated output to be less than some prescribed value, and 2) the closed-loop poles of each local system to be within a pre-specified LMI stability region. In order to alleviate the ill-conditioned LMIs resulting from the interaction of slow and fast dynamic modes, solutions to the problem are given in terms of linear matrix inequalities which are independent of the singular perturbation, [epsilon]. The proposed approach does not involve the separation of states into slow and fast ones and it can be applied not only to standard, but also to nonstandard singularly perturbed nonlinear systems. A numerical example is provided to illustrate the design developed in this paper. Index Terms--H [infinity] fuzzy control, linear matrix inequality (LMI), singularly perturbed systems, Takagi-Sugeno (TS) fuzzy model.

This brief addresses the problem of designing a filter for a class of fuzzy dynamical systems that guarantees that: 1) the [L.sub.2] gain from an exogenous input to a filter error is less or equal to a prescribed value and 2) the filter is quadratically stable in a prespecified linear matrix inequality (LMI) stability region. Based on an LMI approach, solutions to the problem of the [H.sub.[infinity]] fuzzy filtering with quadratic D stability are derived in terms of a family of LMIs. Numerical simulation examples are presented to illustrate the theory development. Index Terms--Fuzzy system models, Lyapunov function, stabilizing controller.

This article focuses on the bumpless transfer $H_{\infty }$ anti-disturbance control problem for switching Markovian LPV systems under a hybrid switching law. A parameter-dependent multiple piecewise disturbance observer-based bumpless transfer control strategy is put forward to reject multiple disturbances and reduce switching bumps. First, a hybrid switching law making full use of determinacy and randomness is proposed to improve the bumpless transfer anti-disturbance level by introducing a fixed dwell time in random switching. Second, a generalized bumpless transfer anti-disturbance specification is given to describe the switching quality at the switching points of switching Markovian LPV systems. Third, a solvability condition is established for the bumpless transfer $H_{\infty }$ anti-disturbance control problem, and a parameter-dependent multiple piecewise disturbance observer-based bumpless transfer controller is designed. Finally, an application example has been supplied to demonstrate the availability of the developed method. [ABSTRACT FROM AUTHOR]