Solution Strategies for a Multiport Container Ship Stowage Problem

Table 2

Algorithm performance of the constructive algorithms from Avriel et al. [3] and from Ding and Chou [4] and their randomized versions on both sets grouped by number of ports (N). Column # shows the number of instances tested in each group, and column # Z shows the total number of solutions found with 0 reshuffles. The average number of reshuffles and average time in seconds are expressed in columns Res. and CPU.

		Avriel et al.						Ding and Chou
		Deterministic, SH			Randomized			Deterministic			Randomized
N	#	# Z	Res.	CPU	# Z	Res.	CPU	# Z	Res.	CPU	# Z	Res.	CPU
Set I
4	95	95	0.0	0.0	95	0.0	0.0	86	0.2	0.1	95	0.0	0.8
6	95	94	0.0	0.0	94	0.0	0.1	69	0.6	0.1	93	0.1	5.0
8	95	86	0.3	0.0	87	0.3	0.5	63	0.7	0.1	91	0.1	5.1
10	95	73	1.5	0.0	74	1.3	4.4	16	2.1	0.1	82	0.2	33.2
12	95	55	2.6	0.0	58	2.3	8.7	22	3.0	0.1	71	0.5	48.7
14	95	35	5.8	0.0	39	4.0	18.7	4	5.2	0.1	58	1.0	89.8
16	95	13	10.1	0.0	19	6.6	39.8	2	5.9	0.1	41	1.7	123.0
18	95	9	16.5	0.0	14	11.1	74.2	1	7.7	0.1	35	2.1	136.9
20	95	5	29.4	0.0	8	18.0	115.5	0	11.2	0.1	8	4.9	190.5
22	95	0	45.5	0.1	2	30.9	208.5	1	12.7	0.1	16	6.1	172.1
Total	950	465	11.2	0.0	490	7.4	47.0	264	4.9	0.1	590	1.7	80.5
Set II
4	120	116	0.1	0.0	116	0.1	0.0	104	0.2	0.0	110	0.1	0.0
6	120	47	2.4	0.0	54	1.7	0.0	33	2.3	0.0	58	1.4	0.0
8	120	13	5.6	0.0	23	3.1	0.1	9	5.9	0.0	22	3.5	0.1
10	120	1	11.1	0.0	9	6.4	0.1	0	11.1	0.0	1	7.7	0.2
12	120	0	18.3	0.0	0	10.4	0.2	0	15.7	0.0	0	10.6	0.2
14	120	0	25.3	0.0	1	15.9	0.3	0	21.1	0.0	0	15.2	0.3
16	120	0	32.1	0.0	0	20.0	0.4	0	27.8	0.0	0	20.0	0.4
Total	840	177	13.5	0.0	203	8.2	0.2	146	12.0	0.0	191	8.3	0.2