Finally, Fig. (bottom) shows that post-repair algorithms suggest more infeasible points than Sobol sampling. The performance of post-repair algorithms strongly depends on the choice of the repair function, especially in the case of a constrained PF. If the repair operator projects infeasible points nonuniformly on the constraint boundary, or if it projects multiple infeasible points on the same place of the constraint boundary, as here in the case of AgNP synthesis, then the optimization will be biased.