Mixed Control Charts Using EWMA Statistics

In this paper, two mixed control charts are designed for process monitoring when the quality characteristic of interest follows a normal distribution. The mixed control chart starts with monitoring the number of non-conforming items but switches to monitoring using exponentially weighted moving average (EWMA) statistic or hybrid EWMA statistic when the decision is indeterminate with the attribute data. The average run lengths are calculated to evaluate the performance of the proposed control charts according to the mean shift. The performance of both control charts is compared with each other and with the existing control chart. Simulation study is given to demonstrate the efficiency of the proposed control charts.

[1]  Chi-Hyuck Jun,et al.  Dispersion chart for some popular distributions under repetitive sampling , 2016 .

[2]  Abdul Haq,et al.  A New Hybrid Exponentially Weighted Moving Average Control Chart for Monitoring Process Mean , 2013, Qual. Reliab. Eng. Int..

[3]  Zhang Wu,et al.  An NP Control Chart Using Double Inspections , 2007 .

[4]  Wu Zhang,et al.  Optimal np Control Charts with Variable Sample Sizes or Variable Sampling Intervals , 2002 .

[5]  H. D.,et al.  An improved double sampling s chart , 2003 .

[6]  Emmanuel Yashchin,et al.  Weighted Cumulative Sum Technique , 1989 .

[7]  Muhammad Azam,et al.  A mixed control chart to monitor the process , 2015 .

[8]  Dongdong Xiang,et al.  Mixed Variables-Attributes Test Plans for Single and Double Acceptance Sampling under Exponential Distribution , 2011 .

[9]  S. W. Roberts.  Control chart tests based on geometric moving averages , 2000 .

[10]  Thong Ngee Goh,et al.  A two-stage decision procedure for monitoring processes with low fraction nonconforming , 2003, Eur. J. Oper. Res..

[11]  Eugenio K. Epprecht,et al.  Adaptive Control Charts for Attributes , 2003 .

[12]  Zhang Wu,et al.  Optimal np control chart with curtailment , 2006, Eur. J. Oper. Res..

[13]  Fred Spiring,et al.  Introduction to Statistical Quality Control , 2007, Technometrics.

[14]  Elisabeth J. Umble,et al.  Cumulative Sum Charts and Charting for Quality Improvement , 2001, Technometrics.

[15]  Muhammad Azam,et al.  Designing of a hybrid exponentially weighted moving average control chart using repetitive sampling , 2015 .

[16]  Zhang Wu,et al.  An attribute chart for monitoring the process mean and variance , 2014 .

[17]  Wei Jiang,et al.  Adaptive CUSUM procedures with EWMA-based shift estimators , 2008 .

[18]  Muhammad Riaz,et al.  Enhancing the performance of EWMA charts , 2011, Qual. Reliab. Eng. Int..

[19]  Trevor A Spedding,et al.  A Synthetic Control Chart for Detecting Fraction Nonconforming Increases , 2001 .

[20]  Muhammad Azam,et al.  A control chart for an exponential distribution using multiple dependent state sampling , 2015 .

[21]  M. A. Rahim,et al.  Economic statistical design of X control charts for systems with gamma(λ, 2) in-control times , 2002 .

[22]  Bin Chen,et al.  A new exponentially weighted moving average control chart for monitoring the coefficient of variation , 2014, Comput. Ind. Eng..

[23]  G. Barrie Wetherill,et al.  Statistical Process Control , 1991 .

[24]  Maysa S. de Magalhães,et al.  Double-sampling control charts for attributes , 2011 .

[25]  Muhammad Azam,et al.  A new exponentially weighted moving average sign chart using repetitive sampling , 2014 .

[26]  Giovanna Capizzi,et al.  An Adaptive Exponentially Weighted Moving Average Control Chart , 2003, Technometrics.

[27]  Mohammad Hossein Fazel Zarandi,et al.  A hybrid fuzzy adaptive sampling - Run rules for Shewhart control charts , 2008, Inf. Sci..

[28]  Joanne M. Sulek,et al.  Measuring performance in multi-stage service operations: An application of cause selecting control charts , 2006 .

[29]  Saddam Akber Abbasi,et al.  On Proper Choice of Variability Control Chart for Normal and Non‐normal Processes , 2012, Qual. Reliab. Eng. Int..

[30]  Babar Zaman,et al.  Mixed CUSUM-EWMA chart for monitoring process dispersion , 2016 .

[31]  Michael B. C. Khoo,et al.  An np control chart for monitoring the mean of a variable based on an attribute inspection , 2009 .

[32]  Eugenio K. Epprecht,et al.  ADAPTIVE SAMPLE SIZE CONTROL CHARTS FOR ATTRIBUTES , 2001 .

[33]  Ronald J. M. M. Does,et al.  A Robust Standard Deviation Control Chart , 2012, Technometrics.