2018/09/28 by Egidi, Michela
#Analysis of PDEs (math.AP) #FOS: Mathematics
paper · doi:10.48550/arxiv.1809.10942
We consider an infinite strip ΩL=(0,2πL)d-1×ℝ, d≥ 2, L>0, and study the control problem of the heat equation on ΩL with Dirichlet or Neumann boundary conditions, and control set ω⊂ΩL. We provide a sufficient and necessary condition for null-controllability in any positive time T>0, which is a geometric condition on the control set ω. This is referred to as "thickness with respect to ΩL" and implies that the set ω cannot be concentrated in a particular region of ΩL. We compare the thickness condition with a previously known necessity condition for null-controllability and give a control cost estimate which only shows dependence on the geometric parameters of ω and the time T.