Dissipation inequalities in nonlinear H/sub infinity /-control

Some results on the problem of disturbance attenuation via measurement feedback, with internal stability, for an affine nonlinear system are summarized and extended. It is shown how some of the simplifying hypotheses considered in earlier analyses of this problem can be weakened. The solution of the problem is shown to be related to the existence of solutions of a pair of Hamilton-Jacobi inequalities in n independent variables, associated with state-feedback and output-injection design.<
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