Simulated Annealing-Based Ant Colony Algorithm for Tugboat Scheduling Optimization

Table 7

Results with different tugboat deployment schemes.

Number of ships	Results with different tugboat deployment schemes
	Scheme 1^1	Scheme 2^2	GAP1^a	Scheme 3^3	GAP2^b
10	2845	2833	−0.42%	2808	−1.30%
15	4205	4186	−0.45%	4159	−1.09%
20	5485	5421	−1.17%	5394	−1.66%
25	6857	6807	−0.73%	6785	−1.05%
30	8381	8325	−0.67%	8299	−0.98%
Average	/	/	−0.69%	/	−1.22%

a(value of 2 − value of 1)/value of 1 × 100%; ^b(value of 3 − value of 1)/value of 1 × 100%.