Development of a Generalized Quick-Switch Sampling System Incorporating Process Loss Considerations

This study focuses on variable quick-switch sampling systems, which have gained increasing attention due to their effectiveness in evaluating lot quality and reducing inspection costs through the use of process capability indices. However, existing VQSS systems generally rely on fixed-switch mechanisms that allow either acceptance-criterion switching or sample-size tightening, while neglecting their combined effect. To overcome this limitation, this paper proposes a generalized variable quick-switch sampling system that integrates a flexible rule-switch mechanism with the process loss index. The proposed system adopts Markov chain theory to characterize inspection-state transitions and derives the operating characteristic function to quantify its discriminatory power. In addition, nonlinear optimization models are developed to determine optimal parameters by minimizing the average sample number subject to specified acceptable and rejectable quality levels and producer’s and consumer’s risk constraints. Numerical results demonstrate that the proposed system outperforms existing VQSS schemes in detecting quality deterioration while maintaining superior cost efficiency, particularly for high-quality submissions. An industrial case study from the pharmaceutical sector further validates the feasibility and practical advantages of the proposed approach.