“…We split the original design variable (thickness h) into two strategies [1,2], formally we denote h = (X, Y ) such that X, Y ∈ U h . The split of the variable h is to construct two allocation tables P and Q in {0, 1} n , where P i + Q i = 1, 1 ≤ i ≤ n and n is the size of h. Let I 12 = {1, ..., n} be a set of indices of cardinality n, I 1 a subset of I 12 of cardinality n 1 , and I 2 its complement of cardinality n 2 , that is to say…”