Table 7. Buckling analysis result of the rib

BL(mm)	Eigen value	M.S.	BL(mm)	Eigen value	M.S.
-830	3.239	2.24	-5,974	1.812	0.81
-1,330	3.070	2.07	-6,475	3.880	2.88
-1,830	3.367	2.37	-6,972	1.356	0.36
-2,330	3.403	2.40	-7,468	1.637	0.64
-2,830	3.296	2.30	-7,965	2.639	1.64
-3,330	3.528	2.53	-8,461	3.002	2.00
-3,830	2.944	1.94	-8,958	3.570	2.57
-4,000	2.026	1.03	-9,458	HIGH	HIGH
-4,000	2.026	1.03	-9,955	HIGH	HIGH
-4,485	1.686	0.69	-10,453	HIGH	HIGH
-4,981	1.193	0.19	-11,046	HIGH	HIGH
-5,477	2.470	1.47