In some manufacturing settings, such as during process start-up and in the case of short production runs, process parameters are unknown, and phase I samples cannot be gathered to accurately estimate control limits for prospective monitoring. Self starting charts can be applied to these low-volume applications. The proposed procedures, which weight current observations according to the information contained in the fault signature, are able to outperform the previously suggested self-starting charts, which neglect the dynamic pattern of the mean change. (42 refs.)
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