crackR (version 0.3-9)

calcInterval: Advance crackR object to the next scheduled inspection

Description

Advance in time through a single inspection interval, adjusting the particle weights and reporting failure probabilities along the way. Estimates of Single Flight Probability Of Failure (SFPOF) will be calculated at intervals specified in the parameter flt.calc.interval, along with the bootstrap estimates of quantiles of SFPOF (if bootstrap.sfpof is TRUE) and an estimate of the probability of failure for each subinterval.

Usage

calcInterval(obj, interval.flights)
"calcInterval"(obj,interval.flights)
"calcInterval"(obj,interval.flights)
"calcInterval"(obj,interval.flights)

Arguments

obj

Object of class Sing, Mult, or CD (each of which is an initialized crackR object created with crackRinit)

interval.flights

Integer, number of flights in the interval

Value

Object of class crackR, advanced in time to the next scheduled inspection and including SFPOF (and various other) results of the interval

Details

When the parameter survival.updating="fbf", the analysis proceeds through the interval flight-by-flight (which takes longer to run and is slower to converge). With survival.updating="int", an approximate analysis is performed which proceeds in INTervals of several flights-at-a-time (the number of flights for each subinterval being determined by parameter flt.calc.interval). While approximate, the "int" version will often converge on a solution more quickly, particularly if failure due to reaching the so-called "critical crack length" is likely. The SFPOF (and various other) results are output at intervals of flt.calc.interval regardless of the value of survival.updating.

References

Halbert, K. "Estimation of Probability of Failure for Damage-Tolerant Aerospace Structures" PhD Thesis, Temple University Department of Statistics, Philadelphia, PA, Apr 2014

See Also

analyze

Examples

data(cp7ext)
cp7ext$Np <- 200
cp7ext.init <- crackRinit(cp7ext)
cp7ext.next <- calcInterval(cp7ext.init, interval.flights=1000)
## crack lengths have grown
head(cp7ext.init$state)
head(cp7ext.next$state)
## SFPOF estimates for the interval are now present
cp7ext.next$results$sfpof