Constrained

Again, the solution is to reduce the complexity of the problem from the multi-objectivity to a mono-objective one. It is possible to combine the two previous methods, that is to minimize a linear weighted function plus a sum of penalty function; the only critical point is to ensure the same order of magnitude of each term of the sum, such that there is not a dictatorship of one term of the sum. The third chance to solve an unconstrained problem (or a constrained, but with some care) is to use the method of the compromise solution: