What Really Caused the ROKS Cheonan Warship Sinking?

Table 1

Comparison of the natural frequency of the simplified model structure ( kg/m²) with the resonant frequency of the realistic model structure ( kg/m²) for the mode and the mode vibrations.  m. () for and () for are the normalized eigenvectors.

(, )	Simplified model	Realistic model
	Natural frequency (Hz) ()	Resonant frequency (Hz)
(0, 1)	8.5 (0.999, 0.022)	8.6
(0, 2)	17.1 (0.999, 0.046)	17.4
(0, 3)	25.5 (0.997, 0.046)	25.7
(0, 4)	34.0 (0.994, 0.105)	35.5
()
(1, 1)	0.9 (0.104, 0.705, 0.702)	1.4
(1, 2)	3.3 (0.175, 0.701, 0.691)	3.5
(1, 3)	6.6 (0.210, 0.698, 0.684)	6.3
(1, 4)	10.4 (0.219, 0.696, 0.684)	9.3
(1, 5)	14.3 (0.212, 0.693, 0.689)	12.4
(1, 6)	18.2 (0.197, 0.686, 0.700)	14.7