A Markov Chain Approximation for ATS Modeling for the Variable Sampling Interval CCC Control Charts
نویسندگان
چکیده
The cumulative conformance count (CCC) charts are widespread in process monitoring of high-yield manufacturing. Recently, it is found the use of variable sampling interval (VSI) scheme could further enhance the efficiency of the standard CCC charts. The average time to signal (ATS) a shift in defect rate has become traditional measure of efficiency of a chart with the VSI scheme. Determining the ATS is frequently a difficult and tedious task. A simple method based on a finite Markov Chain approach for modeling the ATS is developed. In addition, numerical results are given. Keywords—Cumulative conformance count, variable sampling interval, Markov Chain, average time to signal, control chart.
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