Routing Optimisation of Urban Medical Waste Recycling Network considering Differentiated Collection Strategy and Time Windows

Table 5

Comparison between CPLEX solver and PSO algorithm on medium-scale instances.

Instance		CPLEX		PSO
Group	ID
ISG4	1	29	>7200	28	51.62	−3.45%
	2	29	>7200	29	51.64	0.00%
	3	28	>7200	27	56.50	−3.57%
	4	27	>7200	27	52.08	0.00%
	5	29	>7200	28	51.93	−3.45%
ISG5	1	45	>7200	44	132.59	−2.22%
	2	48	>7200	47	129.94	−2.08%
	3	49	>7200	49	130.73	0.00%
	4	48	>7200	46	132.41	−4.17%
	5	51	>7200	49	130.98	−3.92%
ISG6	1	62	>7200	60	212.95	−3.23%
	2	69	>7200	68	213.59	−1.45%
	3	68	>7200	65	211.06	−4.41%
	4	66	>7200	66	213.97	0.00%
	5	64	>7200	62	215.46	−3.13%
Average	—	—	—	—	132.50	−2.34%

Notes: (1) represents the feasible solution obtained by CPLEX in 7200 seconds. denotes the global best solution obtained by PSO algorithm. (2) and are the computation time of CPLEX and PSO algorithm in seconds, respectively. (3) .