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I. Gankevich and A. Degtyarev
Table 1 Values of Weibull shape parameter for different wave characteristics
Characteristic
Weibull shape (k)
Wave height
2
Wave length
2.3
Crest length
2.3
Wave period
3
Wave slope
2.5
Three-dimensionality
2.5
Verification was performed for standing and propagating waves. The corresponding ACFs and quantile-quantile plots of wave characteristics distributions are shown
in Figs. 1, 2 and 3.
Graph tails in Fig. 1 deviate from original distribution for individual wave characteristics, because every wave have to be extracted from the resulting wavy surface to
measure its length, period and height. There is no algorithm that guarantees correct
extraction of all waves, because they may overlap each other. Weibull distribution
right tail represents infrequently occurring waves, so it deviates more than left tail.
Degree of correspondence for standing waves (Fig. 2) is lower for height and
length, is roughly the same for surface elevation and is higher for wave period distribution tails. Lower correspondence degree for length and height may be attributed to
the fact that Weibull distributions were obtained empirically for ocean waves which
are typically propagating, and distributions may be different for standings waves.
Higher correspondence degree for wave periods is attributed to the fact that wave
Fig. 1 Quantile-quantile
plots for propagating waves
x
-2 -1 0
1
2
-2 -1
2
1
2
3
1
2
3
2
4
6
8
2
8
2
4
6
8
0
1
4
6
2
4
6
8
x
elevation
height Y
x
length Y
x
period