Displaying 121 – 140 of 231

Showing per page

Local center manifold for parabolic equations with infinite delay

Hana Petzeltová (1994)

Mathematica Bohemica

The existence and attractivity of a local center manifold for fully nonlinear parabolic equation with infinite delay is proved with help of a solutions semigroup constructed on the space of initial conditions. The result is applied to the stability problem for a parabolic integrodifferential equation.

Local Lipschitz continuity of solutions of non-linear elliptic differential-functional equations

Pierre Bousquet (2007)

ESAIM: Control, Optimisation and Calculus of Variations

The object of this paper is to prove existence and regularity results for non-linear elliptic differential-functional equations of the form div a ( u ) + F [ u ] ( x ) = 0 , over the functions u W 1 , 1 ( Ω ) that assume given boundary values ϕ on ∂Ω. The vector field a : n n satisfies an ellipticity condition and for a fixed x, F[u](x) denotes a non-linear functional of u. In considering the same problem, Hartman and Stampacchia [Acta Math.115 (1966) 271–310] have obtained existence results in the space of uniformly Lipschitz continuous functions...

Monotone iteration for infinite systems of parabolic equations with functional dependence

Anna Pudełko (2007)

Annales Polonici Mathematici

We consider the initial value problem for an infinite system of differential-functional equations of parabolic type. General operators of parabolic type of second order with variable coefficients are considered and the system is weakly coupled. The solutions are obtained by the monotone iterative method. We prove theorems on weak partial differential-functional inequalities as well the existence and uniqueness theorems in the class of continuous bounded functions and in the class of functions satisfying...

Motion planning for a class of boundary controlled linear hyperbolic PDE’s involving finite distributed delays

Frank Woittennek, Joachim Rudolph (2003)

ESAIM: Control, Optimisation and Calculus of Variations

Motion planning and boundary control for a class of linear PDEs with constant coefficients is presented. With the proposed method transitions from rest to rest can be achieved in a prescribed finite time. When parameterizing the system by a flat output, the system trajectories can be calculated from the flat output trajectory by evaluating definite convolution integrals. The compact kernels of the integrals can be calculated using infinite series. Explicit formulae are derived employing Mikusiński’s...

Motion planning for a class of boundary controlled linear hyperbolic PDE's involving finite distributed delays

Frank Woittennek, Joachim Rudolph (2010)

ESAIM: Control, Optimisation and Calculus of Variations

Motion planning and boundary control for a class of linear PDEs with constant coefficients is presented. With the proposed method transitions from rest to rest can be achieved in a prescribed finite time. When parameterizing the system by a flat output, the system trajectories can be calculated from the flat output trajectory by evaluating definite convolution integrals. The compact kernels of the integrals can be calculated using infinite series. Explicit formulae are derived employing ...

Numerical approximations of parabolic differential functional equations with the initial boundary conditions of the Neumann type

Roman Ciarski (2004)

Annales Polonici Mathematici

The aim of this paper is to present a numerical approximation for quasilinear parabolic differential functional equations with initial boundary conditions of the Neumann type. The convergence result is proved for a difference scheme with the property that the difference operators approximating mixed derivatives depend on the local properties of the coefficients of the differential equation. A numerical example is given.

Observations on W 1 , p estimates for divergence elliptic equations with VMO coefficients

P. Auscher, M. Qafsaoui (2002)

Bollettino dell'Unione Matematica Italiana

In this paper, we make some observations on the work of Di Fazio concerning W 1 , p estimates, 1 < p < , for solutions of elliptic equations div A u = div f , on a domain Ω with Dirichlet data 0 whenever A V M O Ω and f L p Ω . We weaken the assumptions allowing real and complex non-symmetric operators and C 1 boundary. We also consider the corresponding inhomogeneous Neumann problem for which we prove the similar result. The main tool is an appropriate representation for the Green (and Neumann) function on the upper half space. We propose...

Currently displaying 121 – 140 of 231