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On the counting of maxima (short contribution). Carl Trygve Stansberg MARINTEK/CeSOS , Trondheim, Norway. CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling, Trondheim, Norway, 24th March 2006. Consider a simplified quadratic model for slow-drift responses.
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On the counting of maxima(short contribution) Carl Trygve Stansberg MARINTEK/CeSOS , Trondheim, Norway CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006
Consider a simplified quadratic model for slow-drift responses y(t) = df HR(f) e j 2f tdf0 N*(f-f0/2) N(f+f0/2) (i.e. a linearly filtered wave energy envelope) HR(f) = {1/(C √[422 + (1-2)2])} e-j arctg[2/(1-)] (linear oscillator) (re: Stansberg (2000) – OMAE) CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006
CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006
CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006
Number of slow-drift maxima in a given record N = Tduration / T:T = ?T = Tz T2? May be OK for narrow-banded waves. Not necessarily OK for slow-drift maximaAlternative:N = Tduration / where = correlation length of time signal, based on spectral bandwidth of response signal, e.g.: CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006
CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006
CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006
”Hidden maxima” Reasonable agreement Correlated maxima CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006
Number of slow-drift maxima in a given record N = Tduration / T:T = ?T = Tz T2? May be OK for narrow-banded waves. Not necessarily OK for slow-drift maximaAlternative:N = Tduration / where = correlation length of time signal, based on spectral bandwidth of response signal, e.g.: CeSOS Workshop on Research Challenges in Probabilistic Load and Response Modelling,Trondheim, Norway, 24th March 2006