§3 可靠度及可靠度函数一、可靠性的数量特征 1.失效率函数 1) 失效率函数的定义前面我们已经谈到了任意时刻t的累积失效概率F(t): F(t)=integral from n=0 tot f(t)dt≈n(t)/N (N—总数;n(t)—失效数) 现在再介绍可靠性的另一个重要的数量特征——失效率,也叫瞬时失效率。它与累积失效概率在意义上是完全不同的。失效率是产品工作到t时刻后,而在随后的⊿t的单位时间内(⊿t→0)发生故障(或 § 3 Reliability and Reliability Functions I. Quantitative Characteristics of Reliability 1. Failure Rate Function 1) Definition of Failure Rate Function Earlier we have talked about the cumulative failure probability F (t) at any time t: F (t) = Now we introduce another important quantitative feature of reliability - the failure rate, also called the failure rate Instantaneous failure rate. It is completely different in meaning from the cumulative probability of failure. The failure rate is the time after the product has been operating until time t (⊿t → 0) (or 单t → 0) during the subsequent unit time ⊿t (or