simu_failTime {abcADM}R Documentation

Simulate samples of failure time using parameters θ


Simulate n observations of failure time from θ = (μ_a, σ_a, μ_b, σ_b, μ_c, σ_c, μ_n, σ_n, μ_σ0 , σ_σ0) for constant load test or ramp load test.


simu_failTime(paras, n, tau_c, t_c, verbose = FALSE)



either a vector or a matrix where each row is θ


number of samples


constant load level (can be set to infinity for ramp load test)


ending time of the constant load test in hours (can be set to infinity for ramp load test)


print information messages to console if TRUE


* The default θ is provided and can be invoked via default_param.

* When sample pieces are subject to the load profile

τ(t) = kt if t <= T_0

τ(t) = τ_c if t > T_0

where τ_c is the selected constant-load level under the ramp-loading rate k, and T_0 is the time required for the load to reach τ_c under the ramp-loading rate k.

* The constant load level is assumed to be reached at the ramp-loading rate (k). The ramp-loading rate is 388,440 psi/hour.

Utilizes routines from the BRENT C++ root-finding library.


Return a matrix of failure times. Each column contains samples from one θ. The name of the output matrix must be in the format "ID_τ_c_t_c(in years)", e.g. simuConstLoad_4500_1Y.


Brent, R. (2002). Algorithms for Minimization without Derivatives. Dover. ISBN: 0-486-41998-3.

Yang, C. H., Zidek, J. V., & Wong, S. W. (2019). Bayesian analysis of accumulated damage models in lumber reliability. Technometrics, 61(2), 233-245.


# simulate data with constant load 4500 psi and test of duration 1Y (8760 hours)
simuConstLoad_4500_1Y = simu_failTime(default_param, 30, 4500, 8760, TRUE)

# simulate data for ramp load
simuRampLoad_Inf_1Y = simu_failTime(default_param, 30, Inf, 8760)

[Package abcADM version 1.0 Index]