Track: Quality

Abstract

This research proposes an optimization algorithm for the economic statistical design of np chart for shift detection in fraction nonconforming. In the literature, less attention has been paid to the economic statistical design of attribute control charts compared with variable control charts although it’s usually easier and faster to handle an attribute quality characteristic rather than a variable quality characteristic.  In this model, the charting parameters of the np chart are optimized to satisfy the objective function which aims to reduce the Expected Total Cost (ETC) and in the meantime, ensure that the false alarm rate and the inspection rate do not exceed the allowable levels. The performance of the proposed optimal np chart will be compared with that of the traditional np chart under different circumstances. A sensitivity analysis will be conducted to study the effectiveness of the optimal np chart under different cost parameters and distributions of the p shift. It is found that the proposed optimal np chart outperforms the traditional np chart.