Monitoring the coefficient of variation: A literature review

Z Jalilibal, A Amiri, P Castagliola, MBC Khoo - Computers & Industrial …, 2021 - Elsevier
There are some situations when the process mean fluctuates from time to time but is still
considered as in-control and the process standard deviation is a linear function of the …

EWMA monitoring schemes for MCV in short production runs with an application to the steel sleeve manufacturing process

XL Hu, JN Zhang, S Zhang, AA Tang… - Computers & Industrial …, 2023 - Elsevier
In industries, multi-variety and small batch processes are extremely common due to the fact
that the production process is moving towards flexible manufacturing to meet the increasing …

One-sided variable sampling interval EWMA control charts for monitoring the multivariate coefficient of variation in the presence of measurement errors

QT Nguyen, V Giner-Bosch, KD Tran… - … International Journal of …, 2021 - Springer
Online monitoring of the multivariate coefficient of variation (MCV) can be of interest in many
real situations in which the dispersion of a multivariate process is meant to remain constant …

Economic design of residuals MEWMA control chart with variable sampling intervals and sample size

L Xue, Q Wang, C Li, L An - Communications in Statistics …, 2023 - Taylor & Francis
In order to improve the monitoring efficiency of the multivariable autocorrelation process and
reduce the cost of process control, an economic design method of residual Multivariate …

Efficient control charts for monitoring process CV using auxiliary information

SA Abbasi - IEEE Access, 2020 - ieeexplore.ieee.org
Coefficient of variation (CV) control charts are a suitable choice for the monitoring of
variation in cases when the process standard deviation is proportional to the process mean …

Variable sampling interval EWMA chart for multivariate coefficient of variation

HN Ayyoub, MBC Khoo, S Saha… - … in Statistics-Theory and …, 2022 - Taylor & Francis
A control chart for monitoring the multivariate coefficient of variation (MCV) is used when the
focus is on monitoring the ratio of relative multivariate variability to the mean of a multivariate …

Multivariate coefficient of variation charts with measurement errors

HN Ayyoub, MBC Khoo, S Saha… - Computers & Industrial …, 2020 - Elsevier
The effects of measurement errors on the performances of multivariate charts have not been
extensively investigated compared with univariate charts. More specifically, control charts for …

Efficient monitoring of coefficient of variation with an application to chemical reactor process

T Mahmood, SA Abbasi - Quality and Reliability Engineering …, 2021 - Wiley Online Library
Control chart is a useful tool to monitor the performance of the industrial or production
processes. Control charts are mostly adopted to detect unfavorable variations in process …

Side‐sensitive modified group runs charts with and without measurement errors for monitoring the coefficient of variation

S Saha, MBC Khoo, P Castagliola… - Quality and Reliability …, 2021 - Wiley Online Library
The coefficient of variation (CV) is used in process monitoring when the process mean and
standard deviation are proportional to each other. In this work, a side‐sensitive modified …

A side‐sensitive synthetic coefficient of variation chart

WC Yeong, PY Lee, SL Lim, KW Khaw… - Quality and Reliability …, 2021 - Wiley Online Library
Control charts for monitoring the coefficient of variation (γ) are useful for processes with an
inconsistent mean (μ) and a standard deviation (σ) which changes with μ, by monitoring the …