Semidiscrete and single step fully discrete approximations for second order hyperbolic equations
Semilinear hyperbolic functional equations
We consider second order semilinear hyperbolic functional differential equations where the lower order terms contain functional dependence on the unknown function. Existence and uniqueness of solutions for t ∈ (0,T), existence for t ∈ (0,∞) and some qualitative properties of the solutions in (0,∞) are shown.
Sharp condition for global existence and blow-up on Klein-Gordon equation.
Sharp regularity theory for second order hyperbolic equations of Neumann type
This note provides sharp regularity results for general, time-independent, second order, hyperbolic equations with non-homogeneous data of Neumann type.
Singular solutions to Protter's problem for the 3-D wave equation involving lower order terms.
Singularly perturbed hyperbolic problems on metric graphs: asymptotics of solutions
We are interested in the evolution phenomena on star-like networks composed of several branches which vary considerably in physical properties. The initial boundary value problem for singularly perturbed hyperbolic differential equation on a metric graph is studied. The hyperbolic equation becomes degenerate on a part of the graph as a small parameter goes to zero. In addition, the rates of degeneration may differ in different edges of the graph. Using the boundary layer method the complete asymptotic...
Solution of a linear model of a single-piston pump by means of methods for differential equations in Hilbert spaces
A mathematical model of a fluid flow in a single-piston pump is formulated and solved. Variation of pressure and rate of flow in suction and delivery piping respectively is described by linearized Euler equations for barotropic fluid. A new phenomenon is introduced by a boundary condition with discontinuous coefficient describing function of a valve. The system of Euler equations is converted to a second order equation in the space where is length of the pipe. The existence, unicity and stability...
Some examples of hyperbolic equations without local solvability
Some new error estimates for finite element methods for second order hyperbolic equations using the Newmark method
We consider a family of conforming finite element schemes with piecewise polynomial space of degree in space for solving the wave equation, as a model for second order hyperbolic equations. The discretization in time is performed using the Newmark method. A new a priori estimate is proved. Thanks to this new a priori estimate, it is proved that the convergence order of the error is in the discrete norms of and , where and are the mesh size of the spatial and temporal discretization, respectively....
Stabilisation pour l'équation des ondes dans un domaine extérieur.
On s'intéresse dans cet article, a la stabilisation de l'équation des ondes dans un domaine extérieur avec condition de Dirichlet...
Stability of higher-level energy norms of strong solutions to a wave equation with localized nonlinear damping and a nonlinear source term
Stability of solutions of differential-operator and operator-difference equations with respect to perturbation of operators
Stability of the Lagrange-Galerkin method with non-exact integration
Stabilization of a wave-wave system.
Stabilization of solutions of an exterior boundary value problem for some class of evolution systems
Stabilization of the wave equation with unbounded feedback of finite range.
Stabilization of wave systems with input delay in the boundary control
In the present paper, we consider a wave system that is fixed at one end and a boundary control input possessing a partial time delay of weight is applied over the other end. Using a simple boundary velocity feedback law, we show that the closed loop system generates a C0 group of linear operators. After a spectral analysis, we show that the closed loop system is a Riesz one, that is, there is a sequence of eigenvectors and generalized eigenvectors that forms a Riesz basis for the state Hilbert...
Statistical mechanics of nonlinear wave equations
Su un problema ai limiti per certe equazioni astratte del secondo ordine
Sufficient optimality conditions for multivariable control problems
We study optimal control problems for partial differential equations (focusing on the multidimensional differential equation) with control functions in the Dirichlet boundary conditions under pointwise control (and we admit state - by assuming weak hypotheses) constraints.