Title
On developing an exponentially weighted moving average chart under progressive setup: An efficient approach to manufacturing processes
Abstract
The exponentially weighted moving average (EWMA) control chart is a memory chart that is widely used in process monitoring to spot small and persistent disturbances in the process parameter(s). This chart requires normality of the quality characteristic(s) of interest and a smaller choice of smoothing parameter. Any deviations from these conditions affect its performance in terms of efficiency and robustness. For the said two concerns, this study develops a new mixed EWMA chart under progressive setup (mixed EWMA-progressive mean [MEP] chart). The proposed MEP chart combines the advantages of robustness (under nonnormal scenarios) and high sensitivity to small and persistent shifts in the process mean. The performance of the proposed MEP control chart is evaluated in terms of average run length and some other characteristics of run length distribution. The assessment of the proposed chart is made under standard normal, student'st, gamma, Laplace, logistic, exponential, contaminated normal and lognormal distributions. The performance of the proposed MEP chart is also compared with some existing competitors including the classical EWMA, the classical cumulative sum (CUSUM), the homogenously weighted moving average, the mixed EWMA-CUSUM, the mixed CUSUM-EWMA and the double EWMA charts. The analysis reveals that the proposal of this study offers a superior design structure relative to its competing counterparts. An application from substrates manufacturing process (in which flow width of the resist is the key quality characteristic) is also provided in the study.
Year
DOI
Venue
2020
10.1002/qre.2716
QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL
Keywords
DocType
Volume
control chart,EWMA,location parameter,nonnormality,progressive mean,robustness,run length
Journal
36.0
Issue
ISSN
Citations 
7.0
0748-8017
0
PageRank 
References 
Authors
0.34
0
5
Name
Order
Citations
PageRank
Zameer Abbas101.69
hafiz zafar nazir2185.78
Noureen Akhtar302.70
Muhammad Mohsin Riaz447586.44
Muhammad Abid54610.69