Isomap-Based Three-Dimensional Operational Modal Analysis

Table 14

PCA and Isomap by LSMS with a real modal damping ratio of 0.03.

Real order	Identified order	LSMS
		PCA (MDS)			Isomap
		MAC	Frequencies	Relative error (%)	MAC	Frequencies	Relative error (%)
1	2	0.8785	1058	0.294	0.8783	1059	0.389
2	1	0.6843	1145	−0.061	0.6837	1145	−0.061
3	3	0.5639	1237	−0.210	0.5634	1237	−0.210
4	4	0.4274	1442	0.007	0.4238	1441	−0.062
5	6	0.6282	1737	−0.172	0.0014	—	—
7	5	0.6564	1872	0.016	0.6495	1874	0.123