Abstract
As technology and living standards improved, people gradually attach importance to the quality. Quality becomes the key of the corporation competitiveness. Process capability indices are effective means of measuring process performance. Most process capability indices have been developed under the assumption that the quality characteristics are normally distributed. However, the voltage, stickiness and lifetime of products generally may possess an non-normal distribution. People are interesting in the lifetime of products so a lifetime performance index CL was proposed and used as a means of measuring product lifetime performance. In the era of high quality, use traditional testing methods need more costs, so acceptance sampling plans are widely used by industry to do the inspection. It protects the risks of producer and customer, reduce the sample size, effectively reflect the quality and provides a decision criteria about accepting the product or not. This study considers the product lifetime with a gamma distribution and uses the uniformly minimum-variance unbiased estimator (UMVUE) of the lifetime performance index to develop resubmitted and repetitive group sampling plans. For the practical purpose, this study presents a step-by-step procedure and tabulates the plan parameters for various combinations of acceptable, rejectable quality levels, producer’s and consumer’s risks and shape parameter. Thus, practitioners can easily know the number of product required for inspection and the corresponding critical value for decision making. Furthermore, this study also uses the results to compare with the single sampling plans. Lastly, provide a practical example to illustrate how to apply this acceptance sampling plans.