Population Stream-Driven Scalable Evolutionary Many-Objective Optimization

Abstract

Solving multi-objective optimization problems with scalable decision variables and objectives is an ongoing challenging task. This study proposes a new evolutionary framework that a series of continuously generated subpopulations are used to approximate the entire Pareto-optimal front. These dynamic subpopulations are abstracted as a population stream. In this framework, one subpopulation is only responsible for searching for a Pareto-optimal solution. Diversity is emphasized among converged solutions coming from different subpopulations, striving to alleviate the conflict between diversity and convergence. To improve the convergence of the newly generated subpopulations, the polynomial fitting method is performed on the obtained solutions to model the relationships among decision variables, which are then used to assist in the generation of new subpopulations. Moreover, an adaptive granularity grid-based environmental selection strategy is proposed to maintain a set of well-diversifying converged solutions. Lastly, extensive experiments are conducted to demonstrate the proposal's superiority by comparing it with 19 representative algorithms in 45 test instances with 3-15 objectives and 300-1500 decision variables.