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
Fault Tree Analysis (FTA) uses which types of logic gates to model combinations of events that lead to system failure?
Answer: AND and OR gates
FTA uses AND gates (all inputs must occur) and OR gates (any input causes output) to model failure logic.
In Fault Tree Analysis, system failure probability is calculated using which mathematical framework?
Answer: Boolean algebra combined with probability theory
FTA applies Boolean logic to identify failure combinations and probability theory to quantify their likelihood.
A minimum cut set in Fault Tree Analysis is defined as:
Answer: The smallest set of basic events whose simultaneous occurrence causes the top event
A minimum cut set identifies the fewest component failures needed to cause the top (system) failure event.
In a k-out-of-n reliability system, the system succeeds when:
Answer: At least k of the n components are functioning
A k-out-of-n system functions if at least k of the total n components are operational.
The chi-square (χ²) distribution is commonly used in reliability engineering to:
Answer: Estimate MTBF confidence intervals from time-terminated test data
Chi-square tables are used with time-terminated and failure-terminated tests to compute one-sided or two-sided MTBF confidence bounds.
System availability (A) is correctly calculated as:
Answer: MTBF divided by (MTBF plus MTTR)
Availability = MTBF / (MTBF + MTTR), representing the proportion of time a system is operational versus being repaired.