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4
Reliability Engineering
4.1 Performance as a Function of Time
Most systems, whether man-made or natural, degrade with time. While
time itself is not liable for the degradation, it is the relevant phenomena
that take place in time that lead these systems to degrade in functionality.
The degradation can be caused by wear and tear from regular use, operat-
ing conditions that are harsher than anticipated, and last but not the least,
design and manufacturing aws. When the degradation reaches a certain
critical level, failure occurs. A system fails when it can no longer perform
its intended function satisfactorily. The end user usually denes ...