A Two-Stage Assembly-Type Flowshop Scheduling Problem for Minimizing Total Tardiness

Table 3

Effectiveness of the lower bounds.

	ACPUT^†		ANNG^‡		NI^#
	8	<0.01	0.01	68	542	90	90
12	0.03	0.58	1008	26498	90	90
16	0.75	111.93	13855	3326995	90	90
20	33.72	1967.48	423917	39077867	90	54

Average CPU time.
^‡Average number of nodes generated in the branch and bound procedure.
^#Number of instances (out of 90 instances) that were solved within 3600 seconds.