We propose a gain-scheduled control law for input constrained systems in the presence of disturbance. The proposed control law has a structure that a high-gain control law and a low-gain control law are interpolated by a single scheduling parameter. The scheduling parameter is computed online by solving a convex optimization problem with LMI constraints. We show that, by using the proposed scheduling algorithm, both feasibility of the control algorithm and closed-loop stability are guaranteed.

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Surface Acoustic Wave (SAW) filters are a key device for mobile communication systems, and the high performance and low-loss of SAW filters has been increasing rapidly. The general design procedures for practical SAW filter are a trial-and-error approach by expert designers. The researches on the design of SAW filters using some different optimization algorithms (i.e. variable neighborhood search) have been the local search method so far. In these researches, the SAW filters are IDT type. Recently, the front-end with ladder type filter has proposed. This filter is low-loss type. The research of the ladder type SAW filter design using the optimization algorithm has not been performed. So, this paper proposed the design method of a ladder type SAW filter using simulated annealing.

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A design problem of delayed feedback controllers in the sampled-data system configuration is considered. Instead of indirect methods via the plant augmentation, we impose certain interpolation conditions on the free parameter of the stabilizing controller parametrization to embed the desired structure into the controller directly. Since the underlying stabilization problem to be solved is independent of the length of the delay, the proposed method avoids a computational burden when the ratio of the periods of the target orbit to the sampling becomes larger.

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