Observability and controllability for a vibrating string with dynamical boundary control.
On a nonlinear equation of the vibrating string
A nonlinear model of the vibrating string is studied and global existence and uniqueness theorems for the solution of the Cauchy-Dirichlet problem are given. The model is then compared to the classical D'Alembert model and to a nonlinear model due to Kirchhoff.
On a variational inequality for the nonhomogeneous degenerated Kirchhoff equation with a frictional damping.
On global real analytic solutions of the degenerate Kirchhoff equation