A number of processes to which statistical control is applied are subject to various effects that cause random changes in the mean value. The removal of these fluctuations is either technologically impossible or economically disadvantageous under current conditions. The frequent occurrence of signals in the Shewhart chart due to these fluctuations is then undesirable and therefore the... https://www.thegreensjunglebeautyshops.shop/product-category/all-over-face-pencil/