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26                                                                UEC Int’l Mini-Conference No.54







                                                              Third, we perform comprehensive variant anal-
                                                              ysis by rigorously benchmarking five adaptive
                                                              configurations across multiple problem domains.
                                                              Fourth, we establish novel hypervolume-centric
                                                              evaluation metrics specifically designed to as-
                                                              sess stability and recovery performance in dy-
                                                              namic environments.   Collectively, these con-
                                                              tributions address critical limitations in exist-
                                                              ing approaches while providing new mechanisms
                                                              for maintaining solution quality during environ-
                                                              mental transitions.


            Figure 1: Comparative HV degradation pat-
            terns during environmental changes in FDA 2       3    Proposed Methodology
            (τ t = 10). Standard DNSGA-II (green) shows
            significant drops during transitions, while the   3.1   Algorithmic Framework
            proposed adaptive method A (blue) and B(red)
            maintains stability.                              The proposed enhancement to DNSGA-II in-
                                                              corporates three synergistic components: First,
                                                              a hypervolume monitoring system continuously
            1.2   Hypervolume as Performance In-              evaluates solution quality throughout environ-
                  dicator                                     mental transitions. Second, an adaptive mu-
                                                              tation controller dynamically modulates muta-
            Hypervolume (HV) has emerged as the gold
            standard metric for multi-objective optimiza-     tion operators based on landscape characteris-
            tion, simultaneously capturing convergence to     tics. Third, a diversity-driven reinitialization
                                                              mechanism activates when diversity metrics fall
            the Pareto front and solution diversity [2].
            In dynamic environments, HV stability during      below critical thresholds, ensuring sustained ex-
            transitions becomes critical. The HV metric is    ploratory capability.
            defined as:
                                                            3.2   Adaptive Mutation Control
                            [
              HV (P) = Λ      [y 1 , r 1 ] × · · · × [y m , r m ] 
                                                              Mutation probability p m dynamically adjusts
                            y∈P                               based on HV trends:
                                                      (1)
            where Λ denotes the Lebesgue measure, P is the                  HV  (t)  − HV  (t−k)
            solution set, y are objective vectors, and r is a       ∆ (t)  =                 × 100%    (2)
                                                                      HV        HV  (t−k)
            reference point.
                                                              where k is a look back window (typically 2-5
            2    Contributions                                generations).
                                                                The adaptation mechanism:
            This work presents four significant advances in
                                                                       
                                                                                    (t)
            dynamic multi-objective optimization.  First,              min p  max , p m + δ p  ∆ (t)  < −θ
                                                                              m                HV
            we develop an adaptive mutation framework           (t+1)             (t)        (t)
                                                               p m   =   max p  min , p m − δ p  ∆  ≥ ϕ
            that dynamically adjusts the mutation rate p m                     m               HV
                                                                       
                                                                        (t)
            in real-time through continuous monitoring of                p m × e −λ           otherwise
            hyper-volume dynamics. Second, we introduce a                                              (3)
            diversity-sensitive reinitialization strategy that  with θ = 5% (degradation threshold), ϕ = 2%
            modulates the solution retention ratio ζ based    (improvement threshold), δ p = 0.05, λ = 0.01,
            on quantitative population distribution metrics.  p min  = 0.01, p max  = 0.3.
                                                                           m
                                                               m
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