STATISTICAL PROPERTIES OF

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28th ACONVEGNO NAZIONALE IDRAULICA E COSTRUZIONI
IDRAULICHEUniversity of Potenza ITALY -
september 16-19, 2002
STATISTICAL PROPERTIES OF NON-LINEAR
WIND-GENERATED WAVES Francesco Fedele 1 Felice
Arena 2
1 University of Vermont, Burlington Vermont
USA 2 University Mediterranea Reggio Calabria
ITALY
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LINEAR STOCHASTIC ANALYSIS
NON-LINEAR STOCHASTIC ANALYSIS
COMPARISON WITH EXPERIMENTAL DATA
CONCLUSIONS
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STOCHASTIC LINEAR ANALYSIS FOR NARROW-BAND SPECTRA
Theory of sea-state (Borgman) Random Gaussian
process stationary ergodic symmetry
crest-trough
Probability of exceedance wave height
(Longuet-Higgins 1952)
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Asymptotic STOCHASTIC LINEAR ANALYSIS
Asymptotic expressions of Boccotti valid for any
shape of spectrum
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NON-LINEAR EFFECTS
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A STOCHASTIC FAMILY FOR NARROW-BAND NON-LINEAR
WAVE PROCESSES
Second order wave processes in open
field Froude-Krylov forces on structures, etc.
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Pdf non-symmetric
Probability of exceedance
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Probability density function
Probabilities of exceedance trough crest
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Froude-Krylov forces on a submerged cylinder
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THE PRESSURE DISTRIBUTION ON THE WALL
Vertical wall
Undisturbed wave field
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THE WAVE FORCE MOMENT ON THE WALL
bottom depth at the wall 1.45m, with kd values
between 1.23 and 1.65.
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FINITE-BAND NON-LINEAR WAVE PROCESSES
General second order solution
Condition of an initial crest
Quasi-determism theory
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CONCLUSIONS
A STOCHASTIC FAMILY OF NON-LINEAR NARROW-BAND
PROCESSES HAS BEEN PROPOSED FOR THE SECOND ORDER
WAVE MECHANICS
MANY PROCESSES IN THE MECHANICS OF SEA WAVES
BELONG TO THE FAMILY
AGREEMENT WITH EXPERIMENTAL DATA
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THE WAVE FORCE MOMENT ON THE WALL