The traditional sampling test method is fit for cases that the number of sample is greater than thirty, it is an approximate calculation method. An unbiased estimation statistics is proposed for the sampling test of maximum maintenance time. Based on χ2 distribution function and normal distribution function, a sampling test method of maximum maintenance time is presented, which the number of sample is allowed less than thirty. The problem of the sampling test of maximum maintenance time is resolved by the method, which the maintenance time is lognormal distributed.
展开▼
