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UEC Int’l Mini-Conference No.54                                                               25








               Improving Adaptation in Evolutionary Dynamic Multi-Objective

                              Optimization via Sparse Solution Selection


                                  Tasin Mobin MOHTADI       ∗1  and Hiroyuki SATO  2

                                  1 UEC Exchange Study Program (JUSST Program)
                        2 Department of Computer and Network Engineering, The University of
                                       Electro-Communications, Tokyo, Japan






                                                       Abstract

                   This paper presents a comprehensive enhancement of the Dynamic Non-dominated Sorting Genetic
                Algorithm II (DNSGA-II) for improved Hypervolume (HV) performance in dynamic multi-objective
                optimization. We introduce a novel framework featuring adaptive mutation control and diversity-
                sensitive reinitialization mechanisms specifically designed to address HV degradation during environ-
                mental transitions. Five distinct adaptive variants were developed and rigorously evaluated on FDA
                1-FDA 5 benchmark problems across multiple change frequency scenarios (τ t = {10, 25, 50} gener-
                ations). Experimental results demonstrate consistent HV improvements up to 18.7% over standard
                DNSGA-II, with the hybrid adaptive mutation-reinitialization approach achieving superior perfor-
                mance across all test cases. The proposed method features three key innovations: 1) Real-time HV
                monitoring for adaptive parameter control, 2) Diversity-guided reinitialization intensity modulation,
                and 3) A counter-based change response mechanism. Statistical validation confirms significant im-
                provements in both HV quality (p < 0.01) and stability metrics, particularly during rapid environmen-
                tal changes. The approach effectively balances exploration-exploitation trade-offs while maintaining
                solution diversity across evolving Pareto fronts.

            Keywords: dynamic optimization, hypervolume, DNSGA-II, adaptive mutation, reinitialization
            strategy, evolutionary computation


            1    Introduction                                 tion quality in the new environment.

                                                                Traditional   multi-objective   algorithms
            1.1   Problem Context and Challenges
                                                              like NSGA-II [1] and its dynamic variants
            Conventional methods for dynamic multi-           (DNSGA-II) encounter significant difficulties
            objective optimization retain solutions after en-  in maintaining solution quality during environ-
            vironmental changes by preserving a randomly      mental transitions. Three primary limitations
                                                              persist: First, substantial hypervolume degra-
            selected subset comprising 1 − ζ of the popula-
            tion. This stochastic approach risks introduc-    dation occurs during change periods, reflecting
            ing selection bias, as the retained solutions may  compromised Pareto front quality.   Second,
            inadequately represent critical regions of the    these algorithms exhibit delayed response
            Pareto front or lack necessary diversity. Con-    characteristics, resulting in slow convergence
                                                              following environmental shifts. Third, diversity
            sequently, the optimization efficiency for the
            changed problem is compromised due to subop-      collapse during stable periods leads to pre-
            timal transfer of historical information, poten-  mature convergence.   These limitations stem
            tially delaying convergence and degrading solu-   primarily from static re-initialization strate-
                                                              gies that fail to adapt to changing problem
               ∗ Supported by JASSO Scholarship.              landscapes.
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