“…In the context of partial differential equations (PDEs), problems of this type are often referred to as PDE-constrained optimization problems and have been studied extensively over the last decades (see [37,85] for introductions to the field). Optimal control problems for FDEs have previously been studied in literature such as [2,3,54,55,65,74]. However, they were mostly considering one-dimensional spatial domains, since the direct treatment of higher dimensions was too expensive.…”