X charts with variable sampling intervals
Technometrics
Multiobjective economic design of an X control chart
Computers and Industrial Engineering
A new approach to robust economic design of control charts
Applied Soft Computing
Economic design of variable sampling intervals T2 control charts using genetic algorithms
Expert Systems with Applications: An International Journal
Adaptive R charts with variable parameters
Computational Statistics & Data Analysis
Optimal design of the double sampling X chart with estimated parameters based on median run length
Computers and Industrial Engineering
Hi-index | 12.05 |
Double sampling X@? control chart (DS) which is a Shewhart-type chart can reduce sample size and detect small process shift fast. In process monitoring of real industry, observations may be interdependent and correlated, and an original DS design will occur high cost for the wrong determination of the process state. In this study, an economic design model of DS is developed based on Yang and Hancock's assumption of correlation and Lorenzen and Vance's cost model to determine sample size, sampling interval, and coefficients of control limits and warring limits. The genetic algorithms (GAs) are applied to solve this economic design model of DS for the determination of the optimal parameters. A real example of IC packaging process is given to illustrate the model application. Sensitivity analysis shows the influence of different model parameters on the DS chart designs.