The integrated model of the Kolmogorov-Smirnov distribution-free statistic approach to process control and maintenance

This research is aimed to find the optimal values of four variables (n, h, L, k) that minimize the cost of integrated system approach to process control from considering the basis of the EWMA control chart integrated model (Charongrattanasakul and Pongpullponsak, 2009, 2011) and Kolmogorov-Smirnov (KS) control chart Khrueasom and Pongpullponsak (2014). The proposed mathematical model is used to analyze the cost of the integrated model before the genetic algorithms (GA) approach is carried out in order to calculate the optimal values of four variables (n, h, L, k) that minimize the hourly cost. Subsequently, they are subjects to the nonparametric linear regression test in order to confirm the optimal values of four variables. A comparison between four policies of integrated model KS and other models indicates that the integrated KS model has a better economic behavior when it is distribution-free. Finally, the performance or average run length (ARL) obtained from the KS model is greater than that of the general model.