Different Transfer Functions for Binary Particle Swarm Optimization with a New Encoding Scheme for Discounted {0-1} Knapsack Problem

Figure 1

Box plot of 8 instances: (a) IDKP3, (b) IDKP9, (c) UDKP3, (d) UDKP9, (e) WDKP3, (f) WDKP9, (g) SDKP3, and (h) SDKP9.

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