A Hybrid Genetic Algorithm for Satellite Image Downlink Scheduling Problem

Table 2

The results of HGA under two circumstances, removing the delay rule from SGA (no delay) and removing the deletion rule from SGA (no deletion) (the utility difference between the normal HGA and HGA under the corresponding circumstance is denoted as ; the utility obtained by normal HGA is denoted as ; the instances that gets higher when the deletion rule is removed are marked in bold).

Instance	HGA (no delay)					HGA (no deletion)
			(%)		(%)			(%)		(%)
50-1	10939	43	12.75	3767	25.62	14469	47	14.34	237	1.61
50-2	12196	48	17.71	3530	22.45	15678	49	17.85	48	0.31
50-3	11138	45	15.69	3827	25.57	14128	48	16.20	837	5.59
50-4	10528	43	16.52	4083	27.94	14039	47	18.27	572	3.91
50-5	11949	44	16.80	3387	22.09	15262	47	17.59	74	0.48
100-1	29225	89	30.86	4176	12.50	33267	94	32.84	134	0.40
100-2	29805	91	29.49	3316	10.01	32433	93	29.71	688	2.08
100-3	28287	89	32.45	3101	9.88	30465	92	33.68	923	2.94
100-4	29668	92	32.19	3769	11.27	32310	96	33.50	1127	3.37
100-5	28700	91	30.32	3852	11.83	31916	94	31.55	636	1.95
150-1	45131	127	44.76	2933	6.10	48080	135	47.97	−16	−0.03
150-2	44829	131	47.14	2174	4.63	46411	135	48.83	592	1.26
150-3	43910	128	46.76	2943	6.28	46420	134	48.35	433	0.92
150-4	45578	130	45.15	2961	6.10	48132	136	47.52	407	0.84
150-5	44136	130	47.34	3576	7.49	47352	138	49.78	360	0.75
200-1	58228	170	54.71	2375	3.92	60410	170	55.18	193	0.32
200-2	58943	167	57.35	2566	4.17	60892	169	57.74	617	1.00
200-3	59487	169	59.51	2344	3.79	60887	169	58.76	944	1.53
200-4	61330	172	56.73	2414	3.79	63483	174	57.13	261	0.41
200-5	60220	171	52.96	2480	3.96	62845	172	53.38	−145	−0.23
250-1	67979	189	67.97	2463	3.50	70035	192	68.71	407	0.58
250-2	70223	198	65.45	1675	2.33	71467	201	66.56	431	0.60
250-3	70394	200	65.47	2302	3.17	72530	200	65.73	166	0.23
250-4	70937	195	66.24	1178	1.63	72157	199	68.15	−42	−0.06
250-5	71184	196	64.36	1954	2.67	72872	201	65.71	266	0.36
300-1	78439	221	71.13	805	1.02	79553	220	70.69	−309	−0.39
300-2	78622	218	69.94	2602	3.20	80956	221	70.29	268	0.33
300-3	78131	219	70.97	922	1.17	79172	219	72.06	−119	−0.15
300-4	79219	220	69.24	1521	1.88	79948	217	68.11	792	0.98
300-5	78127	217	69.46	2547	3.16	79496	219	68.80	1178	1.46