A New Control Scheme for Phase‐II Monitoring of Simple Linear Profiles in Multistage Processes

In this paper, a new control scheme is proposed for Phase-II monitoring of simple linear profiles in multistage processes. In this scheme, an approach based on the U transformation is first applied to remove the effect of the cascade property involved in multistage processes. Then, a single max-EWMA-3 control statistic is derived based on the adjusted parameter estimates for simultaneous monitoring of all the parameters of a simple linear profile in each stage. Not only is the proposed scheme able to detect both increasing and decreasing shifts but it also has the feature of identifying the out-of-control parameter responsible for the source of process shift. Using extensive simulation experiments, the performance of the proposed method is evaluated and is compared with the ones of some other available methods for both weak and strong autocorrelations. Moreover, the diagnostic performance of the proposed method is evaluated. The results show that the proposed scheme performs well and works better than the competing methods. The application of the proposed method is illustrated at the end using a numerical example. Copyright © 2016 John Wiley & Sons, Ltd.

[1]  Majid Khedmati,et al.  Phase II monitoring of general linear profiles in the presence of between‐profile autocorrelation , 2016, Qual. Reliab. Eng. Int..

[2]  Fugee Tsung,et al.  Monitoring General Linear Profiles Using Multivariate Exponentially Weighted Moving Average Schemes , 2007, Technometrics.

[3]  Connie M. Borror,et al.  Process monitoring for mean shifts for multiple stage processes , 2007 .

[4]  Zhonghua Li,et al.  An exponentially weighted moving average scheme with variable sampling intervals for monitoring linear profiles , 2010, Comput. Ind. Eng..

[5]  William H. Woodall,et al.  A review and analysis of cause-selecting control charts , 1993 .

[6]  Smiley W. Cheng,et al.  Monitoring Process Mean and Variability with One EWMA Chart , 2001 .

[7]  Longcheen Huwang,et al.  Monitoring General Linear Profiles When Random Errors Have Contaminated Normal Distributions , 2014, Qual. Reliab. Eng. Int..

[8]  Rassoul Noorossana,et al.  Simple linear profiles monitoring in the presence of within profile autocorrelation , 2009, Comput. Ind. Eng..

[9]  J. A. Robinson,et al.  Analysis of Variation Transmission in Manufacturing Processes—Part I , 1999 .

[10]  Lan Kang,et al.  On-Line Monitoring When the Process Yields a Linear Profile , 2000 .

[11]  Rassoul Noorossana,et al.  Monitoring Two Dependent Process Steps Using Special Variable Sample Sizes and Sampling Intervals Cause‐Selecting Control Charts , 2012, Quality and Reliability Engineering International.

[12]  William H. Woodall,et al.  Current research on profile monitoring , 2007 .

[13]  Fugee Tsung,et al.  Statistical monitoring of multi-stage processes based on engineering models , 2008 .

[14]  A. Amiri,et al.  Phase I monitoring of generalized linear model-based regression profiles , 2015 .

[15]  Seyed Taghi Akhavan Niaki,et al.  Designing a multivariate–multistage quality control system using artificial neural networks , 2009 .

[16]  Jianjun Shi,et al.  Quality control and improvement for multistage systems: A survey , 2009 .

[17]  D. Hawkins Multivariate quality control based on regression-adjusted variables , 1991 .

[18]  Fugee Tsung,et al.  A Change Point Approach for Phase I Analysis in Multistage Processes , 2008, Technometrics.

[19]  Fugee Tsung,et al.  Directional MEWMA Schemes for Multistage Process Monitoring and Diagnosis , 2008 .

[20]  Fugee Tsung,et al.  Statistical process control for multistage processes with binary outputs , 2013 .

[21]  Fugee Tsung,et al.  False Discovery Rate-Adjusted Charting Schemes for Multistage Process Monitoring and Fault Identification , 2009, Technometrics.

[22]  Rassoul Noorossana,et al.  Statistical Analysis of Profile Monitoring: Noorossana/Profile Monitoring , 2011 .

[23]  S. T. A. Niaki,et al.  On the Monitoring of Linear Profiles in Multistage Processes , 2014, Qual. Reliab. Eng. Int..

[24]  Seyed Taghi Akhavan Niaki,et al.  The Max EWMAMS control chart for joint monitoring of process mean and variance with individual observations , 2011, Qual. Reliab. Eng. Int..

[25]  D. Montgomery,et al.  Multivariate statistical process monitoring and diagnosis with grouped regression‐adjusted variables , 1999 .

[26]  Douglas M. Hawkins,et al.  Regression Adjustment for Variables in Multivariate Quality Control , 1993 .

[27]  Mahmoud A. Mahmoud,et al.  On the Monitoring of Linear Profiles , 2003 .

[28]  Fugee Tsung,et al.  Statistical process control for multistage manufacturing and service operations: A review and some extensions , 2008 .

[29]  Rickie J. Domangue,et al.  Some omnibus exponentially weighted moving average statistical process monitoring schemes , 1991 .

[30]  William H. Woodall,et al.  A Comparison of the Performance of Phase II Simple Linear Profile Control Charts when Parameters are Estimated , 2015, Commun. Stat. Simul. Comput..