Problem of non-normality in statistical quality control: a case study in a surface mine
نویسنده
چکیده
Quality of ore varies in the complete spectrum of mining operations. Depending upon the quality control practices at mines, grade variation may follow a systematic pattern or an erratic fluctuation. The different statistical quality control techniques, especially control charts, are used for continuous monitoring of grade variation. The main purpose of the application of control charts is to identify the root causes of quality variation based on which corrective actions are taken to remove irregular grade fluctuation. Some studies on the application of control charts were conducted in the mineral industry for improving the quality of ore (Khuntia et al., 1991; Samanta, et al., 1998). These studies explored the application of the Shewhart X —
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