Fuzzy conditional reliability for some continuous distributions

الملخص EN

Fuzzy set theory has become a useful tool in the mathematical modeling of problem in operation research, including reliability engineering and applied recently in various fields.

The problem of reliability with fuzziness is discussed by means of fuzzy mathematics In the world, there exists much fuzzy knowledge ; knowledge that is vague, imprecise, uncertain, ambiguous, inexact or probabilistic in natural.

Human thinking and reasoning frequently involve fuzzy information, originating from inherently inexact human concepts.

Fuzzy sets have been able provide solutions to many real world problems.

Suppose that an item has survived to time a, where T is the total time, then U = T-a is the future life random variable.

The conditional reliability function defined by : (t |a) = Pr (item survives a further time t survives to a) Fuzzy reliability is the probability of a device performing its purpose in varying degrees of success for the period of time intended under operating conditions encountered The aim of this paper find the fuzzy condition reliability of a some continuous distribution where the random variable independent and dependent.