“…In this approach, the optimality conditions for the constrained minimization problem (1) are solved simultaneously for the state, the adjoint and the design variable in a SQP-like fashion. Because the simulation is directly integrated in the optimization process, these methods are often called Simultaneous Analysis and Design (SAND), all-at-once approach, or one-shot approach [10,11,12,13,14,15,16]. It has been observed numerically -at least for steady state PDEs -that the full space methods can outperform the reduced space methods by about one order of magnitude measured in iteration counts and runtime [8,17].…”