Design and construction of a variables switch-based sampling system for product acceptance determination

Abstract

This article proposes a variables switch-based sampling system, called the quick-switching sampling (QSS) system, based on one-sided capability indices for product acceptance determination when the quality characteristic of interest follows a normal distribution and has a unilateral specification limit. The QSS system is among the simplest sampling systems that involves a normal plan and a tightened plan under switching rules. The operating characteristic function of the proposed system is derived from an exact sampling distribution. The plan parameters are determined by a mathematical model that ensures the prescribed quality and risk requirements. The performance and behavior of the proposed variables QSS system are discussed and compared with those of conventional plans. For practical purposes, this article provides tables of the plan parameters under various conditions, and illustrates the method on an example taken from the integrated circuit industry.