원문정보
초록
영어
When the linear correlation of the quality variables are considerably high, multivariate control charts may be a more effective way than univariate charts which operate quality variables and process parameters individually. Performances and efficiencies of the multivariate control charts under multivariate normal process has been considered. Some numerical results are presented under small scale of the shifts in the process to see the improvement of the efficiency of EWMA chart and CUSUM chart, which use past quality information, comparing to Shewart chart, which do not use quality information. We can know that the decision of the optimum value of the smoothing constant in EWMA structure or the reference value in CUSUM structure are very important whether we adopt combine-accumulate technique or accumulatecombine technique under the given condition of process.
목차
1. Introduction
2. Accumulate-Combine and Combine-Accumulate Techniques
2.1. Combine-Accumulate Technique
2.2. Accumulate-Combine Technique
3. Variable Sampling Intervals Structure
4. Comparison and Efficiencies of the Considered Charts
References