156583.fig.0010a
(a)
156583.fig.0010b
(b)
156583.fig.0010c
(c)
Figure 10: Typical time signals of vertical sensor V4 and PSD estimates of them: upper row is for undamaged model, lower row is for 22.2% delaminated model: (a) due to swept sine excitations; (b) due to random excitations; (c) due to impact excitations.