In production processes, there are two types of
variations that affect production quality - - variations
produced by chance causes and variations produced by
assignable causes. One of the main instruments in quality
control used to control quality by distinguishing between
variations produced by chance causes and a real process...
Control charts are designed to monitor population parameters. Selection of a
control chart sampling plan involves determination of the frequency of samples, size
of each sample, and critical values to determine when the system is sending an out-of-control signal. Since the main use of control charts is in industry, a...
When the nonconformities are independent, a multivariate control chart for nonconformities called a demerit control chart using a distribution approximation technique called an Edgeworth Expansion, is proposed. For a demerit control chart, an exact control limit can be obtained in special cases, but not in general. A proposed demerit control...