  In this paper, we present a control-design method based on the energy-Casimir
method for infinite-dimensional, boundary-actuated port-Hamiltonian systems
with two-dimensional spatial domain and second-order Hamiltonian. The resulting
control law depends on distributed system states that cannot be measured, and
therefore, we additionally design an infinite-dimensional observer by
exploiting the port-Hamiltonian system representation. A Kirchhoff-Love plate
serves as an example in order to demonstrate the proposed approaches.
