Perturbation Properties of a Class of Infinite-Dimensional Systems with Unbounded Control and Observation

摘要

The report defines a class of infinite-dimensional systems with unbounded input and output operators which are closed under state feedback, output injection and output feedback perturbations. An explicit criterion for spectral systems to belong to the class is given. As an application, it extends the finite dimensional result on the equivalence of input-output stability and exponential stability to the class. The theory is illustrated by a p.d.e. model of a beam with viscous damping.