The double sampling (DS) chart can reduce the sample size when monitoring the process mean. In this study, Duncan's cost model was modified by adding the statistical constraints to develop the design model of DS chart for the optimization of design parameters--sample size, control limit...

A combination of double sampling X¯ chart and variable sampling intervals X¯ chart (DSVSI) can successfully reduce the detection time of small mean shift. Before a DSVSI X¯ chart is used, its design parameters should be determined. This study constructs an economic design model of DSVSI X¯...

A combination of double sampling the [image omitted]  chart and the variable sampling interval of the [image omitted]  chart (DSVSI [image omitted]  chart) increases the sensitivity in the small shift detection. A usual assumption of control charts is that the process observations are...