Multivariate control charts for monitoring covariance matrix: a review
AB Yeh, DKJ Lin, RN McGrath - Quality Technology & Quantitative …, 2006 - Taylor & Francis
In this paper, we review multivariate control charts designed for monitoring changes in a
covariance matrix that have been developed in the last 15 years. The focus is on control …
covariance matrix that have been developed in the last 15 years. The focus is on control …
A review of dispersion control charts for multivariate individual observations
JO Ajadi, Z Wang, IM Zwetsloot - Quality Engineering, 2021 - Taylor & Francis
A multivariate control chart is designed to monitor process parameters of multiple correlated
quality characteristics. Often data on multivariate processes are collected as individual …
quality characteristics. Often data on multivariate processes are collected as individual …
Monitoring multivariate process variability for individual observations
L Huwang, AB Yeh, CW Wu - Journal of Quality technology, 2007 - Taylor & Francis
Most of the existing control charts for monitoring multivariate process variability are based on
subgroup sizes greater than one. In many practical applications, however, only individual …
subgroup sizes greater than one. In many practical applications, however, only individual …
A multivariate control chart for simultaneously monitoring process mean and variability
Recently, monitoring the process mean and variability simultaneously for multivariate
processes by using a single control chart has drawn some attention. However, due to the …
processes by using a single control chart has drawn some attention. However, due to the …
Control charts for monitoring linear profiles with within‐profile correlation using Gaussian process models
Y Zhang, Z He, C Zhang… - Quality and Reliability …, 2014 - Wiley Online Library
Profile monitoring is the utilization of control charts for checking the stability of the quality of a
product over time when the product quality is characterized by a function at each time point …
product over time when the product quality is characterized by a function at each time point …
Nonparametric multivariate covariance chart for monitoring individual observations
Parametric and nonparametric multivariate control charts that are proven very useful in
monitoring the covariance matrix of multivariate normally or “nearly” normally distributed …
monitoring the covariance matrix of multivariate normally or “nearly” normally distributed …
A study of EWMA chart with transformed exponential data
The exponentially weighted moving average (EWMA) chart has been shown to be effective
in detecting small process shifts and predicting the process level at the next time period. In …
in detecting small process shifts and predicting the process level at the next time period. In …
A combined synthetic&X chart for monitoring the process mean
Z Wu, Y Ou, P Castagliola… - International Journal of …, 2010 - Taylor & Francis
The Shewhart X chart (or X chart) is widely used to monitor the mean of a quality
characteristic x. This chart decides the process status based on the magnitude of the sample …
characteristic x. This chart decides the process status based on the magnitude of the sample …
Enhancing the performance of CUSUM scale chart
Control charts act as the most important statistical process monitoring tool, widely used for
the purpose of identifying unusual variations in process parameters. Researchers have …
the purpose of identifying unusual variations in process parameters. Researchers have …
Monitoring the covariance matrix via penalized likelihood estimation
In many industrial multivariate quality control applications, based on the engineering and
operational understanding of how the process works, when the process variability is out of …
operational understanding of how the process works, when the process variability is out of …