Economic Design of Moving Average Control Chart for Continued and Ceased Production Process

Abstract

In this article following the approach of Lorenzen and Vance, an economic design of moving average control chart is developed for ceased as well for continued production during control actions. The performance of the control charts is compared for the two production modes by means of the loss cost per time unit. The ceased production mode yields about 30% saving in the loss cost when compared to that of the continued production. The example given provides some insight to the sensitivity of the model. Brought to you by | University of Georgia Libraries Authenticated Download Date | 5/26/15 6:48 PM[14] Yu, F.J. and Chen, Y.S. (2005): Economic design of moving average control charts.

Economic design of moving average control chart for non-normally distributed data: a comparative study

“…If we put δ 1 = δ 2 = 1, the cost function represents loss cost function for continuous process, whereas if we put δ 1 = δ 2 = 0, it represents loss cost function for ceased process. If we put δ 1 = 1, δ 2 = 0, the function represents loss cost function for (1-0) semi-ceased process, where the process is continued during the search of an assignable cause and ceased during repair of the cause, if occurred (Patil and Rattihalli, 2009). The cost function developed is a complicated function of three design parameters (n, h, k), hence to get desired values of parameters and the expected loss, we use algorithmic procedure instead of direct derivative method.…”

“…To illustrate the comparison between the normal and non-normal process as well between continued and ceased process, here we consider the example by Koo and Case (1990), which is used by Patil and Rattihalli (2009) with some modifications and also by Yu and Chen (2005). Following are the values of input parameters selected.…”

“…These designs are also based on normal quality characteristics and most of them are for the continuous process. Patil and Rattihalli (2009) have proposed the economic design for continuous as well as ceased MA process control chart. In this paper, considering non-normal input quality characteristics, we have developed the combined loss cost function for MA control chart under continuous, ceased and semi-ceased process model using unified approach by Lorenzen and Vance (1986).…”

Economic design of moving average control chart for non-normal data using variable sampling intervals

“…If we put δ 1 = δ 2 = 1, the cost function represents loss cost function for continuous process and if we put δ 1 = δ 2 = 0, it represents loss cost function for ceased process. If we use δ 1 = 1, δ 2 = 0, the function represents loss cost function for (1-0) semi-ceased process, where the process is continued during the search of an assignable cause and ceased during repair of the cause, if occurred (Patil and Rattihalli [17]). …”

“…Chen and Yang [7] have obtained economic design for moving average control charts under continuous flow process. Patil and Rattihalli [17] have developed economic design of MA control chart which works simultaneously for both continued and ceased processes.…”