Neural Multi-Objective Combinatorial Optimization with Diversity Enhancement (Appendix) A Reference point and hypervolume ratio

In the inference process, the submodel is used to solve the corresponding subproblem. The input dimensions of the node features vary with different problems. A masking mechanism is adopted in each decoding step to ensure the solution feasibility. For MOTSP, the visited nodes are masked. NHDE-M usually spends relatively more inference time than MDRL with the same number of weights.