Track: Quality Control and Quality Management
Abstract
This article proposes a salient feature to enhance the detection speed of the EWMA scheme based on the power of the difference between the actual number and the target in-control number of nonconforming items. We refer to it as wEWMA scheme and show that the traditional EWMA chart is a special case of the proposed scheme. We discuss the optimal design procedure of the scheme, including the determination of its charting parameters to ensure the best overall performance. The results reveal that the developed wEWMA scheme has better overall detection effectiveness than the traditional EWMA chart. Specifically, the former outperforms the latter by 35% for the tested cases under different specifications.