Experimental Evaluation for the Microvibration Performance of a Segmented PC Method Based High Technology Industrial Facility Using 1/2 Scale Test Models

Table 4

Comparison of natural frequency and response magnitude by the impact test on FAB floor.

Mode	Frequency (Hz)			Response (um/Ns)
	Nonsegmented; Model	Segmented; Model	Ratio; (%)	Nonsegmented; Model	Segmented; Model	Ratio; (%)
1st	16.2	15.2	94.0	13.1	7.1	54.2
2nd	25.8	24.3	93.9	6.1	3.4	55.8
3rd	33.3	30.4	91.5	5.2	4.1	78.9