CRE Statistical Methods and Reliability Modeling Flashcards
6 cards from real CRE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CRE Statistical Methods and Reliability Modeling flashcards as text
Accelerated Life Testing (ALT) uses elevated stress levels primarily to accomplish which goal?
Answer: Reduce test time by inducing failures faster than normal operating conditions
ALT compresses the failure timeline so reliability predictions can be made without waiting for failures under normal conditions.
The Arrhenius model in reliability testing is used to describe the effect of which stress variable on failure rates?
Answer: Temperature
The Arrhenius model relates reaction rate (failure rate) to temperature using the activation energy equation.
For two components in parallel with reliabilities R1 and R2, the combined system reliability is calculated as:
Answer: 1 − (1 − R1)(1 − R2)
Parallel system reliability = 1 minus the probability that both components fail simultaneously.
In reliability testing, confidence intervals are used to:
Answer: Quantify uncertainty in reliability point estimates
Confidence intervals provide a range within which the true reliability parameter is expected to fall with a stated probability.
The inverse power law model is commonly applied in accelerated life testing for which type of stress?
Answer: Voltage or mechanical stress
The inverse power law relates failure rate to non-thermal stresses such as voltage, pressure, or vibration.
Monte Carlo simulation in reliability analysis is primarily used to:
Answer: Generate simulated failure times mathematically from probability distributions
Monte Carlo simulation randomly samples input distributions to model system behavior and estimate reliability metrics.