A variant of NSGA-II for solving priority based optimization problems

Many real life problems require optimization of more than one objective functions, these problems are known as multi-objective optimization problems. Although many algorithms are available in literature to solve these types of problems [2, 3, 4, 5, 21] but they treat every objective function equally. Sometimes, on the basis of problem to be optimized, different objective functions can be assigned different priority. In this way, we can reduce the burden of searching in all objective directions, those having higher priority will contribute in search space, those having low priority will be selected by local search from the assigned search space. For dealing such type of problems a modified version of NSGA-II is presented in the paper. This modified algorithm is used to solve a multi-objective problem, which is related to rotary furnace that is used in small-scale foundry.