In this research, an iterative approach is employed to analyze and classify the states of univariate quality control systems. To do this, a measure (called the belief that process is incontrol) is first defined and then an equation is developed to update the belief recursively by taking new observations on the quality characteristic under consideration. Finally, the upper and the lower control ...

Among innovations and improvements occurred in the past two decades on the techniques and tools used for statistical process control (SPC), adaptive control charts have shown to substantially improve the statistical and/or economical performances. Variable sampling intervals (VSI) control charts are one of the most applied types of the adaptive control charts and have shown to be faster than tr...

a new method is developed for a fast identification of the stability situation of industrial processes. the proposed method includes two factor ratios of the control constants for the upper and lower control limits to process these constants. an indication ratio is then defined as the ratio of the maximum data range value to the difference between the maximum and average values for individual d...

BACKGROUND The Shipman Inquiry recommended mortality rate monitoring if it could be 'shown to be workable' in detecting a future mass murderer in general practice. AIM To examine the effectiveness of cumulative sum (CUSUM) charts, cross-sectional Shewhart charts, and exponentially-weighted, moving-average control charts in mortality monitoring at practice level. DESIGN OF STUDY Analysis of ...

Originally developed at Bell Laboratories by Dr Walter Shewhart [1] in 1924 specifically to help detect statistical changes in process quality, control charts have since become one of several primary tools of quality control and process improvement. Quality control charts are chronological graphs of process data that, although based in statistical theory, are easy for practitioners to use and i...

Numerous papers have been written to show which combinations of Shewhart-type quality-control charts are optimal for detecting systematic shifts in the mean response of a process, increases in the random error of a process, and linear drift effects in the mean response across the assay batch. One paper by Westgard et al. (Clin Chem 1977;23:1857-67) especially seems to have attracted the attenti...

Vibration condition monitoring is a non-devastating technique that can be performed to detect tooth cracks propagating in gear systems. This paper proposes apply new methodology using time-domain analysis, frequency-domain and statistical process control charts (SPCC) for crack detection of 10 DOF dynamic model spiral bevel system (SBGS). The mesh stiffness effect used the has been studied anal...

Statistical Process Control (SPC) is widely applied to monitor and improve highly integrated and automated manufacturing processes. Adopting proper SPC charts and corresponding detection mechanisms is crucial for a TFT-LCD manufacturing process. This study conducts an empirical study of highly complex TFT-LCD manufacturing processes to identify the most suitable SPC method. The TFT-LCD manufact...