Approximate controllability of semilinear functional equations in Hilbert spaces
Approximate and complete controllability for semilinear functional differential systems in Hilbert spaces is studied. Sufficient conditions are established for each of these types of controllability. The results address the limitation that linear systems in infinite-dimensional spaces with compact semigroup cannot be completely controllable. The conditions are obtained by using the Schauder fixed point theorem when the semigroup is compact and the Banach fixed point theorem when the semigroup is not compact.
semilinear functional differential systems
scientific article; zbMATH DE number 1866564