측정오차를 고려한 Xbar-S 관리도의 경제적 설계

Abstract

For statistical process control, the process data are collected by the measurement system. But, the measurement system may have instrument system may have instrument error or/and operator error. In the measured values of products, the total observed variance consists of process variance and variance due to error of measurement system. In this paper, we design more practical Xbar-S control chart considering estimated measurement error. The effects of measurement error on the expected total cost and design parameters are investigated.