On the quenching of solutions of the wave equation with a nonlinear boundary condition.
On the regularity of boundary traces for the wave equation
On the set of solutions of some nonconvex nonclosed hyperbolic differential inclusions
We consider a class of nonconvex and nonclosed hyperbolic differential inclusions and we prove the arcwise connectedness of the solution set.
On the singularities of 3-D Protter's problem for the wave equation.
On the solvability of a Darboux type non-characteristic spatial problem for the wave equation.
On the solvability of a multidimensional version of the Goursat problem for a second order hyperbolic equation with characteristic degeneration.
On the solvability of a spatial problem of Darboux type for the wave equation.
On the solvability of parabolic and hyperbolic problems with a boundary integral condition.
On the solvability of the multidimensional version of the first Darboux problem for a model second-order degenerating hyperbolic equation.
On the stability of the coupling of 3D and 1D fluid-structure interaction models for blood flow simulations
We consider the coupling between three-dimensional (3D) and one-dimensional (1D) fluid-structure interaction (FSI) models describing blood flow inside compliant vessels. The 1D model is a hyperbolic system of partial differential equations. The 3D model consists of the Navier-Stokes equations for incompressible Newtonian fluids coupled with a model for the vessel wall dynamics. A non standard formulation for the Navier-Stokes equations is adopted to have suitable boundary conditions for the...
On the uniqueness of solutions and the convergence of successive approximations in the Darboux problem for certain differential equations of the type
On the wave equations with memory in noncylindrical domains.
On the well-posedness and regularity of the wave equation with variable coefficients
An open-loop system of a multidimensional wave equation with variable coefficients, partial boundary Dirichlet control and collocated observation is considered. It is shown that the system is well-posed in the sense of D. Salamon and regular in the sense of G. Weiss. The Riemannian geometry method is used in the proof of regularity and the feedthrough operator is explicitly computed.
Optimal control systems by time-dependent coefficients using CAS wavelets.
Optimal LQ-feedback control for a class of first-order hyperbolic distributed parameter systems
The Linear-Quadratic (LQ) optimal control problem is studied for a class of first-order hyperbolic partial differential equation models by using a nonlinear infinite-dimensional (distributed parameter) Hilbert state-space description. First the dynamical properties of the linearized model around some equilibrium profile are studied. Next the LQ-feedback operator is computed by using the corresponding operator Riccati algebraic equation whose solution is obtained via a related matrix Riccati differential...
Oscillation of solutions for systems of hyperbolic equations of neutral type.
Oscillations of higher order differential equations of neutral type
In this paper, sufficient conditions have been obtained for oscillation of solutions of a class of th order linear neutral delay-differential equations. Some of these results have been used to study oscillatory behaviour of solutions of a class of boundary value problems for neutral hyperbolic partial differential equations.
Otto Vejvoda passed away
Output feedback stabilization of a one-dimensional wave equation with an arbitrary time delay in boundary observation
The stabilization with time delay in observation or control represents difficult mathematical challenges in the control of distributed parameter systems. It is well-known that the stability of closed-loop system achieved by some stabilizing output feedback laws may be destroyed by whatever small time delay there exists in observation. In this paper, we are concerned with a particularly interesting case: Boundary output feedback stabilization of a one-dimensional wave equation system for which the...
Output feedback stabilization of a one-dimensional wave equation with an arbitrary time delay in boundary observation∗
The stabilization with time delay in observation or control represents difficult mathematical challenges in the control of distributed parameter systems. It is well-known that the stability of closed-loop system achieved by some stabilizing output feedback laws may be destroyed by whatever small time delay there exists in observation. In this paper, we are concerned with a particularly interesting case: Boundary output feedback stabilization of a...