Economic Design of $ar{X}$ Control Chart Using a Surrogate Variable

Lee, Tae-Hoon; Lee, Jae-Hoon; Lee, Min-Koo; Lee, Joo-Ho

Journal of Korean Society for Quality Management > Volume 37(2); 2009 > Article

Journal of Korean Society for Quality Management 2009;37(2): 46-.

대용변수를 이용한 $ar{X}$ 관리도의 경제적 설계

이태훈¹, 이재훈², 이민구², 이주호²

¹한국원자력연구원 수소생산원자로기술개발부
²충남대학교 정보통계학과

Economic Design of $ar{X}$ Control Chart Using a Surrogate Variable

Tae-Hoon Lee¹, Jae-Hoon Lee², Min-Koo Lee², Joo-Ho Lee²

¹Nuclear Hydrogen Reactor Technology Development Division, Korea Atomic Energy Research Institute
²Department of Information & Statistics, Chungnam National University

ABSTRACT

The traditional approach to economic design of control charts is based on the assumption that a process is monitored using a performance variable. However, various types of automatic test equipments recently introduced as a part of factory automation usually measure surrogate variables instead of performance variables that are costly to measure. In this article we propose a model for economic design of a control chart which uses a surrogate variable that is highly correlated with the performance variable. The optimum values of the design parameters are determined by maximizing the total average income per cycle time. Numerical studies are performed to compare the proposed $ar{X}$ control charts with the traditional model using the examples in Panagos et al. (1985).

Key Words: X bar Control Chart;Performance Variable;Surrogate Variable;Economic Design;