Single-Machine Scheduling with Fixed Periodic Preventive Maintenance to Minimise the Total Weighted Completion Times

Table 14

Results of heuristic algorithms compared to the lower bounds.

n	WSPTBF			WSPTFF			WSPTFB + LIS
	Min	Max	Ave	Min	Max	Ave	Min	Max	Ave
20	0.52	55.97	22.90	0.52	40.49	16.09	0.46	34.97	12.20
25	2.95	66.47	24.50	1.58	49.59	16.74	1.35	37.30	13.73
30	4.21	63.59	24.85	3.07	46.05	17.42	2.59	39.96	14.60
35	5.36	57.79	26.52	3.37	45.97	17.86	2.81	36.98	15.22
40	6.56	67.72	27.11	3.50	46.63	17.97	3.17	43.00	15.24
45	6.03	67.24	27.82	3.51	44.29	18.27	3.37	41.48	15.60
50	6.51	73.43	28.24	3.53	44.65	18.88	3.14	42.55	15.79
60	7.17	60.10	27.77	4.34	44.69	18.42	3.77	40.72	15.61
70	7.70	65.09	28.11	4.91	43.94	18.19	4.04	38.99	15.52
80	7.18	63.82	28.83	4.55	42.33	18.55	3.62	37.89	15.71
90	8.75	65.95	28.51	4.28	43.15	18.46	3.92	40.74	15.62
100	9.95	61.84	29.31	4.49	42.36	18.51	3.93	39.12	15.67
200	9.16	65.63	29.86	4.75	42.01	18.31	4.00	40.52	15.66
300	8.99	63.83	29.91	4.70	41.40	17.92	4.12	40.26	15.40
400	9.87	64.63	30.48	4.64	41.08	18.04	4.15	39.03	15.43
500	10.85	64.19	30.90	4.80	40.10	18.07	4.23	38.91	15.57
1000	11.44	65.04	31.06	4.72	40.21	17.79	4.24	38.03	15.25