A STUDY OF COMBINED CUSUM-SHEWHART (???) CONTROL CHARTS

The cumulative sum (CUSUM) control chart is known to be sensitive to slight changes in the process quality characteristics. The design of this control chart is based on a series of cumulative sums of the statistic derived from the data. To monitor both changes of the mean and variance simultaneously and comprehensively, we propose a combined CUSUM-Shewhart ??? control chart based on a single statistic for normally distributed characteristics. It has been demonstrated that the proposed combined chart detects the out-of-control state with smaller average run length (ARL) as compared to other charts like CUSUM ??? , omnibus EWMA, and the standard ??? control chart

کلیدواژه ها:

CUSUM control chart ، Shewhart control chart ، ??? control chart ، CUSUM-Shewhart ??? scheme