Multi-Item Multiperiodic Inventory Control Problem with Variable Demand and Discounts: A Particle Swarm Optimization Algorithm

Table 2

Different problems and their optimal TMF values obtained by the two algorithms.

Problem	𝑚	𝑁	𝑀1	TB	Objective values		MOPSO				MOGA
					MOPSO	MOGA	𝐶1	𝐶2	Pop	Gen	𝑃𝐶	𝑃𝑚	Pop	Gen
1	1	3	2000	30000	18510	18510	2	2.5	30	200	0.6	0.1	40	500
2	2	3	3000	85000	44622	44943	1.5	2.5	20	200	0.5	0.08	30	200
3	3	3	5000	170000	85830	86089	1.5	2	30	500	0.6	0.08	50	300
4	2	4	3500	130000	92758	93423	2	2	30	100	0.7	0.2	50	200
5	3	4	5000	240000	147480	146450	1.5	2.5	40	100	0.6	0.2	50	200
6	4	3	6000	260000	132910	133400	2.5	1.5	20	200	0.6	0.08	40	500
7	5	3	9000	370000	153840	154550	2	2.5	40	200	0.6	0.2	50	200
8	6	3	8800	360000	214620	215510	1.5	2.5	30	500	0.5	0.1	30	200
9	7	3	10500	400000	265020	266020	2	2	30	200	0.7	0.1	40	300
10	8	5	12000	470000	322850	328250	2.5	2.5	30	500	0.6	0.08	50	200
11	8	8	15000	550000	431245	442100	2	2	20	200	0.7	0.2	30	300
12	9	5	15000	530000	438790	449835	1.5	2.5	40	100	0.7	0.2	50	300
13	9	8	18000	600000	495470	513725	2	2	40	500	0.7	0.08	50	500
14	9	9	20000	630000	553276	571250	1.5	2.5	20	100	0.5	0.1	40	500
15	10	5	20000	620000	579030	593167	2.5	2.5	20	200	0.5	0.2	30	200
16	10	8	25000	700000	642870	665890	1.5	2.5	40	200	0.7	0.08	30	200
17	10	10	34000	780000	710035	731280	1.5	1.5	30	200	0.5	0.08	50	500
18	10	15	45000	900000	823210	852400	2	2.5	20	500	0.6	0.1	40	500
19	11	10	40000	850000	827659	859080	1.5	2.5	30	500	0.6	0.1	30	500
20	11	15	45000	870000	867840	897500	2.5	2	40	100	0.7	0.2	50	200
21	12	10	48000	870000	902720	948956	1.5	2.5	30	200	0.5	0.2	50	300
22	12	12	53000	900000	932760	974380	1.5	2	30	100	0.6	0.2	40	200
23	12	15	58000	950000	965470	1023950	2	2.5	20	100	0.5	0.2	30	200
24	13	10	52000	890000	973200	1043569	1.5	1.5	20	500	0.7	0.08	40	300
25	13	13	55000	930000	985439	1089210	1.5	2.5	40	500	0.6	0.1	30	300
26	13	15	62000	980000	1056810	1104325	2	2.5	40	500	0.5	0.1	40	500
27	15	8	57000	900000	1059835	1110360	2	2	20	200	0.6	0.08	50	500
28	15	10	63000	900000	1095430	1176509	2.5	2.5	30	100	0.6	0.2	30	200
29	15	12	68000	950000	1198720	1332900	2.5	1.5	30	500	0.5	0.1	40	200
30	15	15	75000	1000000	1256980	1447905	1.5	2	20	500	0.6	0.08	50	200
31	16	12	70000	940000	1298750	1473400	2	1.5	40	100	0.7	0.1	50	500
32	16	15	80000	1050000	1454328	1772349	1.5	2.5	40	500	0.7	0.2	40	200
33	17	15	87000	1100000	1543890	1809850	2	2	40	200	0.7	0.1	50	500
34	17	17	93000	1140000	1630215	1865780	2.5	2.5	30	500	0.6	0.1	40	300
35	18	10	80000	1000000	1678345	1890437	1.5	1.5	30	100	0.7	0.08	50	300
36	18	15	98000	1150000	1768950	1924670	2	2.5	20	500	0.5	0.08	40	300
37	18	18	103000	1230000	1832450	1987320	1.5	2	30	100	0.7	0.1	40	200
38	20	10	100000	1200000	1876895	1998230	2.5	2.5	20	500	0.6	0.1	50	500
39	20	15	108000	1260000	1904564	2035689	1.5	2	30	500	0.7	0.2	50	500
40	20	20	115000	1330000	1987350	2154670	1.5	1.5	30	100	0.7	0.08	30	500
Mean	—	—	—	—	897145	971541	—	—	—	—	—	—	—	—
St. Dev	—	—	—	—	581013	652778	—	—	—	—	—	—	—	—