Abstract
Acceptance sampling plan is a practical tool in quality management field. It can provide the vendor and the buyer a decision rule for lot sentencing to meet their requirements of product quality. Several acceptance sampling plans have been developed by using different strategies, one of them is quick switching sampling system (QSS system). QSS system is one of two-plan sampling systems, which involves only normal and tightened inspections and has a rule for switching between these two types of inspection. The normal inspection can be used when the quality is found to be good and tightened inspection is used when the quality of a product deteriorated. Traditional acceptance sampling plan always focus on conforming to specification limits, but according to modern quality improvement theories or Taguchi’s quality philosophy, reduction of deviation from the target value should serve as the guiding principle rather than conforming to specification limits. And this concept can reduce the loss caused by the deviation. For this reason, this paper develops a variables QSS system based on process loss index Le. Because QSS system has three different types, we will study each of them. Moreover, the behavior of the proposed plan under various parameters is studied and the plan parameters are determined by an optimization problem. The advantages of the proposed plan are discussed compared with the existing plans using the process loss function. Finally, an application example is presented for illustration and discussion.