Umberto Biccari, Víctor Hernández-Santamaría, Judith Vancostenoble. Existence and cost of boundary controls for a degenerate/singular parabolic equation (2020).
Abstract. In this paper, we consider the following degenerate/singular parabolic equation
where are two real parameters.
We prove the boundary null controllability by means of a control acting either at or at the point of degeneracy and singularity . Besides we give sharp estimates of the cost of controllability in both cases in terms of the parameters and . The proofs are based on the classical moment method by Fattorini and Russell and on recent results on biorthogonal sequences.