SPECTRUM (DB) 
SPECTRUM (DB) 
SPECTRUM (DB) 
ROLLING 
3 N=51 
3.00 Nes12 3.00 512 
AR 3 RECTANGULAR 
FILTER 
1.00 Fp. teed 
2 
= 
> 
c 
b 
B 
-1.00 a -1.00 
-3.00 -3.00 
0.00 0.20 0.40 0.00 0.20 0.40 
FREQUENCY FREQUENCY 
WAVE HEIGHT OF ACTUAL SEA 
Boo N=512 Heo N=512 
ARB zx 
a RECTANGULAR 
I FILTER 
= 
> 
-1.00 = (1.00 
oO 
w 
a 
72) 
-3.00 -3.00 
0.00 0.20 0.40 0.00 0.20 0.40 
FREQUENCY FREQUENCY 
HORIZONTAL ACCELERATION OF ENGINE BED 
N=512 
N=2512 RECTANGULAR 
AR 10 FILTER 
oa 
So 
3.00 = 300 
2 
c 
i= 
oO 
w 
oa 
n 
1.00 1.00 
0.00 10.00 20.00 0.00 10.00 20.00 
FREQUENCY FREQUENCY 
(a) AR model fitting. (b) FET. method. 
SPECTRUM (DB) 
SPECTRUM (DB) 
SPECTRUM (DB) 
3.00 N=512 
LAG = 64 
HANNING 
WINDOW 
1.00 
-1.00 
-3.00 
0.00 0:20 0.40 
FREQUENCY 
1.00 
N=512 
LAG = 64 
HANNING 
WINDOW 
-1.00 
-3.00 
0.00 0.20 0.40 
FREQUENCY 
N=512 
LAG = 64 
HANNING 
3.00 WINDOW 
1.00 
-1.00 
0.00 10.00 20.00 
FREQUENCY 
(c) B—T method. 
Fig. 7.7. Comparison of the spectrum through AR—model fitting and 
conventional methods. 
(From Yamanouchi, et al.52) 
234 
