1. Definition:
Reliability: Probability that the product functions at or after time t
Failure rate: Probability that the product does not function before time t
2. Two Typical Lifetime Distributions
1) Negative Exponential (or Exponential Decay)
Observed when a single component determines the life of the entire system
2) Normal Distribution
Observed when the average of multiple components determines the life of the entire system
3. Mean Time Between Failures (MTBF)
1）If distribution is negative exponential, then set λ= 1/MTBF
2）If distribution is Normal, then set μ= MTBF
