An Improved Particle Swarm Optimization for Selective Single Machine Scheduling with Sequence Dependent Setup Costs and Downstream Demands

Table 3

Comparison results for the effectiveness of adaptive strategy in VNS.

		PSOrandomVNS		PSOadaptiveVNS
		Gap (%)	CPU (s)	Gap (%)	CPU (s)
3	50	0.00	17.21	0.00	12.74
	80	0.06	83.67	0.06	71.35
	100	0.54	150.00	0.46	150.00
	120	0.52	180.00	0.41	180.00
	150	1.43	225.00	1.34	225.00
	200	2.85	300.00	2.69	300.00
5	50	0.00	38.92	0.00	22.06
	80	0.17	200.00	0.17	200.00
	100	0.69	250.00	0.62	250.00
	120	1.24	300.00	1.15	300.00
	150	1.71	375.00	1.66	375.00
	200	3.58	500.00	3.34	500.00
7	50	0.02	29.05	0.02	24.86
	80	0.86	280.00	0.86	280.00
	100	1.39	350.00	1.34	350.00
	120	1.37	420.00	1.31	420.00
	150	2.14	525.00	1.97	525.00
	200	4.42	700.00	4.18	700.00