Purpose - The aim of this paper is to present a synthetic chart based on the non-central chi-square statistic that is operationally simpler and more effective than the joint X̄ and R chart in detecting assignable cause(s). ...

Recent theoretical studies have shown that the X̄ chart with variable sampling intervals (VSI) and the X̄ chart with variable sample size (VSS) are quicker than the traditional X̄ chart in detecting shifts in the process. ...

The usual practice in using a control chart to monitor a process is to take samples of size n from the process every h hours. This article considers the properties of the X̄ chart when the size of each sample depends on ...

We present the non-conventional design of no charts used for the surveillance of processes characterized by a very low fraction nonconforming, with a costly and/or time-consuming inspection procedure. which makes the ...

This abstract presents a case study approach based on qualitative methods and data that aimed a detailed examination of an environment, a particular subject or situation. The objective of this work is to improve the painting ...

In this article, we propose the S chart with variable charting statistic to control the covariance matrix as an alternative to the use of the bivariate |S| chart and the trivariate VMAX chart. As usual, samples are regularly ...

A model for the joint economic design of X̄ and R control charts is developed. This model assumes that the process is subject to two assignable causes. One assignable cause shifts the process mean; the other shifts the ...

The mechanical harvesting is an important stage in the production process of soybeans and, in this process; the loss of a significant number of grains is common. Despite the existence of mechanisms to monitor these losses, ...

In this article, we consider the T(2) chart with double sampling to control bivariate processes (BDS chart). During the first stage of the sampling, n(1) items of the sample are inspected and two quality characteristics ...