We consider the quality of a process which can be characterized by a general linear profile where the random error has a contaminated normal distribution. On the basis of trimmed least squares estimation, new control charts for monitoring the coefficient parameters and/or the error variance of the profile are proposed. Simulation studies show that the proposed control charts outperform the exis...

The define–measure–analyze–improve–control (DMAIC) approach is a five-strata approach, namely DMAIC. This approach is the scientific approach for reducing the deviations and improving the capability levels of the manufacturing processes. The present work elaborates on DMAIC approach applied in reducing the process variations of the stub-end-hole boring operation of the manufacture of cra...

Use of risk adjusted control charts for monitoring patients’ surgical outcomes is now popular.These charts are developed based on considering the patient’s pre-operation risks. Change point detection is a crucial problem in statistical process control (SPC).It helpsthe managers toanalyzeroot causes of out-of-control conditions more effectively. Since the control chart signals do not necessarily...

Traditional literature on statistical quality control discusses separately multivariate control charts for independent processes and univariate control charts for autocorrelated processes. We extend univariate residual monitoring to the multivariate environment, and propose using vector autoregressive residuals (VAR) to monitor multivariate processes in the presence of serial correlation. We ma...

One of the existing problems of multi-attribute process monitoring is the occurrence of high number of false alarms (Type I error). Another problem is an increase in the probability of not detecting defects when the process is monitored by a set of independent uni-attribute control charts. In this paper, we address both of these problems and consider monitoring correlated multi-attributes proce...

Process monitoring through control charts is a quite popular practice in statistical process control. From a statistical point of view, a superior control chart is one that has an efficient design structure, but having resistance against unusual situations is of more practical importance. To have a compromise between the statistical and practical purposes, a natural desire is to have a control ...

In this study, different ranked-based sampling (RBS) schemes are used to design a sensitive control chart monitor the small or moderate shifts in process mean and named combined EWMA moving average RBS (CEM-RBS) charts. The run-length (ARL) standard deviation of (SDRL) through Monte Carlo simulation runs computed evaluate performance proposed charts comparison with existing such as MA, EWMA, EW...