Power Spectral Density Functions
Construction and evaluation of different Power Spectral Density (PSD) functions. Correpsonding theory and literature can be found here Semi-empirical-PSD-functions.
Index
UncertaintyQuantification.CloughPenzien
UncertaintyQuantification.EmpiricalPSD
UncertaintyQuantification.KanaiTajimi
UncertaintyQuantification.ShinozukaDeodatis
Types of PSD functions
UncertaintyQuantification.CloughPenzien Method
CloughPenzien(ω::AbstractVector{<:Real}, S_0::Real, ω_f::Real, ζ_f::Real, ω_g::Real, ζ_g::Real)
Constructs a CloughPenzien
instance representing a power spectral density function with the given parameters.
Arguments / Parameters
ω::AbstractVector{<:Real}
: A vector of angular frequencies.S_0::Real
: A scaling factor.ω_f::Real
: Frequency parameter for the first oscillator.ζ_f::Real
: Damping ratio for the first oscillator.ω_g::Real
: Frequency parameter for the second oscillator.ζ_g::Real
: Damping ratio for the second oscillator.
Returns
A discretized CloughPenzien
power spectral density function specified by given arguments (parameters).
Example
w = 0:0.1:10
S_0 = 1.0
ω_f = 2.0
ζ_f = 0.05
ω_g = 3.0
ζ_g = 0.1
cp_psd = CloughPenzien(w, S_0, ω_f, ζ_f, ω_g, ζ_g)
UncertaintyQuantification.KanaiTajimi Method
KanaiTajimi(ω::AbstractVector{<:Real}, S_0::Real, ω_0::Real, ζ::Real) -> KanaiTajimi
Constructs a KanaiTajimi
instance representing a power spectral density function with the given parameters.
Arguments
ω::AbstractVector{<:Real}
: A vector of angular frequencies.S_0::Real
: A scaling factor.ω_0::Real
: Natural frequency of the oscillator.ζ::Real
: Damping ratio of the oscillator.
Returns
A discretized KanaiTajimi
power spectral density function specified by given arguments (parameters).
Example
w = 0:0.1:10
S_0 = 1.0
ω_0 = 2.0
ζ = 0.05
kt = KanaiTajimi(w, S_0, ω_0, ζ)
UncertaintyQuantification.ShinozukaDeodatis Method
ShinozukaDeodatis(ω::AbstractVector{<:Real}, σ::Real, b::Real)
Constructs a ShinozukaDeodatis
instance representing a power spectral density function with the given parameters.
Arguments
ω::AbstractVector{<:Real}
: A vector of angular frequencies.σ::Real
: A hyperparamter related to the variance of the stochastic process.b::Real
: A parameter related to the correlation length of the stochastic process.
Returns
A discretized ShinozukaDeodatis
instance with the power spectral density function specified by given arguments (parameters).
Example
w = 0:0.1:10
σ = 1.0
b = 0.5
sd = ShinozukaDeodatis(w, σ, b)
UncertaintyQuantification.EmpiricalPSD Type
EmpiricalPSD(ω::AbstractVector{<:Real}, p::AbstractVector{<:Real}) -> EmpiricalPSD
Constructs an EmpiricalPSD
instance with the given angular frequencies and manually provided power spectral density values.
Arguments
ω::AbstractVector{<:Real}
: A vector of angular frequencies.p::AbstractVector{<:Real}
: A vector of power spectral density values corresponding to the frequencies inω
.
Returns
A discretized EmpiricalPSD
instance with manually pre-specified provided power spectral density values.
Example
w = 0:0.1:10
p_values = rand(length(w)) # Example empirical PSD values
emp_psd = EmpiricalPSD(w, p_values)