Tham khảo tài liệu 'assessing product reliability_2', kỹ thuật - công nghệ, điện - điện tử phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | . Reliability or survival function ENGINEERING STATISTICS HANDBOOK hW tools raids search BACK NExf 8. Assessing Product Reliability . Introduction . What are the basic terms and models used for reliability evaluation . Reliability or survival function Survival is the complementary event to failure The reliability of the system is the product of the reliability functions of the components The Reliability FunctionR t also known as the Survival Function S t is defined by R t S t the probability a unit survives beyond time t. Since a unit either fails or survives and one of these two mutually exclusive alternatives must occur we have R t 1 - F t F t 1 - R t Calculations using R t often occur when building up from single components to subsystems with many components. For example if one microprocessor comes from a population with reliability function Rm t and two of them are used for the CPU in a system then the system CPU has a reliability function given by Rcpu t Rm2 t since both must survive in order for the system to survive. This building up to the system from the individual components will be discussed in detail when we look at the Bottom-Up method. The general rule is to calculate the reliability of a system of independent components multiply the reliability functions of all the components together. NIST SEMATECH HOME TOOLS it AIDS SEARCH BACK NEXT http div898 handbook apr section1 5 1 2006 10 41 24 AM . Failure or hazard rate ENGINEERING STATISTICS HANDBOOK hW tools raids lỉEÂtCH BACK Nixf 8. Assessing Product Reliability . Introduction . What are the basic terms and models used for reliability evaluation . Failure or hazard rate The failure rate is the rate at which the population survivors at any given instant are falling over the cliff The failure rate is defined for non repairable populations as the instantaneous rate of failure for the survivors to time t during the next instant of time.
