Semilinear parabolic equations with forcing terms are discussed, and sufficient conditions for every classical global solution of boundary value problems to be unbounded on a cylindrical domain in R. The approach used is to reduce the multi-dimensional problems to one-dimensional problems for first-order ordinary differential inequalities.

In this paper we study optimal control problems governed by semilinear parabolic equations. We obtain necessary optimality conditions in the form of an exact Pontryagin’s minimum principle for distributed and boundary controls (which can be unbounded) and bounded initial controls. These optimality conditions are obtained thanks to new regularity results for linear and nonlinear parabolic equati...

In the present paper, stability and convergence properties of linear multistep methods are investigated. The attention is focused on parabolic problems and variable stepsizes. Under weak assumptions on the method and the stepsize sequence an asymptotic stability result is shown. Further, stability bounds for linear nonautonomous parabolic problems with Hölder continuous operator are given. With...