An Enhanced Auxiliary Information‐Based EWMA‐t Chart for Monitoring the Process Mean

Applied Sciences

Shin‐Li Lu¹  Jen‐Hsiang Chen² 

[1] Department of Industrial Management and Enterprise Information, Aletheia University, New Taipei City 251, Taiwan;Department of Information Management, Shih Chien University Kaohsiung Campus, Kaohsiung City 845, Taiwan;

关键词: average run length;    auxiliary information;    ewma‐t chart;    gwma‐t chart;    statistical process control;   

DOI  :  10.3390/app10072252

来源: DOAJ

【 摘 要 】

The exponentially weighted moving average t chart using auxiliary information (AIB-EWMA-t chart) is an effective approach for monitoring small process mean shifts when the process standard deviation is unstable or poorly estimated. To further enhance the sensitivity of the AIB-EWMA-t chart, in this study, we propose an AIB generally weighted moving average (GWMA) t chart (AIB-GWMA-t chart) to monitor the process mean. The existing EWMA-t, GWMA-t, and AIB-EWMA-t charts are special cases of the AIB-GWMA-t chart. Numerical simulation studies indicate that the AIB-GWMA-t chart performs uniformly and substantially better than the EWMA-t and GWMA-t charts in terms of average run length. Moreover, the AIB-GWMA-t chart with large design and adjustment parameters also outperforms the AIB-EWMA-t chart when the correlation coefficients are within a certain range. An illustrative example is provided to highlight the efficiency of the proposed AIB-GWMA-t chart in detecting small process mean shifts.

【 授权许可】

Unknown