Table 3.

Comparison between EM and NM frequencies at step 2.

Mode	${\mathbf{f}}_{\mathbf{E}\mathbf{M}} \left[\mathbf{Hz}\right]$	Step 2 ${\mathbf{f}}_{\mathbf{N}\mathbf{M}} \left[\mathbf{Hz}\right]$	$\mathbf{\Delta }{\mathbf{f}}_2 (\%)$
1	1.654	1.610	2.66
2	1.800	1.871	−3.94
3	4.236	4.272	−0.85
4	4.955	5.036	−1.63
5	9.767	8.504	12.93