In some applications of quality control charts it is very important to quickly detect small or moderate shifts in the characteristic that is being monitored when process control starts. In such cases, CUSUM charts with fast initial response (FIR) perform very well. However, optimal performance...

Textual data has become increasingly common in business analytic data sets. While concept-based text mining offers a method of extracting meaningful information from text data, methods for monitoring of customer perceptions of business processes and products that are discussed in...

Extrusion is one of the fundamental production methods in the polymer processing industry and is used in the production of a large number of commodities in a diverse industrial sector. Being an energy intensive production method, process energy efficiency is one of the major concerns and the...

Thermal stability is of major importance in polymer extrusion, where product quality is dependent upon the level of melt homogeneity achieved by the extruder screw. Extrusion is an energy intensive process and optimisation of process energy usage while maintaining melt stability is necessary in...

When monitoring a variable x in statistical process control, it is necessary to monitor both the mean and variability. Recently, it is found that, if both the mean shift δμ and standard deviation shift δσ follow the uniform distribution, many control charts with different complicacy are...