A Modified Statistical Design Model of Double Sampling X Control Chart

The double sampling (DS) control chart can efficaciously reduce sample sizes and increase performance of process monitoring. Hsu (Int. j. prod. res., vol. 42, no. 5, pp. 1043-1047) mentioned that the statistical design model of DS X control chart could merely minimize sample sizes during in-control process monitoring but fail to decrease sample sizes during detection of process shifts. In this study, with minimization of sample sizes for both in-control process and out-of-control process, a multi-objective programming method and genetic algorithm are proposed for statistical designs of DS X control chart. In comparison with both statistical design models, it is quite obvious that our model can effectively lower sample sizes of two process situations.