Search Results - subject:"statistical process control."

Identifying the Out of Control Variable in a Multivariate Control Chart

Maravelakis, Petros - 2006

The identification of the out of control variable, or variables, after a multivariate control chart signals, is an appealing subject for many researchers in the last years. In this paper we propose a new method for approaching this problem based on principal components analysis. Theoretical...

Persistent link: https://www.econbiz.de/10012779055

An Examination of the Robustness to Non Normality of the Ewma Control Charts for the Dispersion

Maravelakis, Petros - 2006

The EWMA control chart is used to detect small shifts in a process. It has been shown that, for certain values of the smoothing parameter, the EWMA chart for the mean is robust to non normality. In this article, we examine the case of non normality in the EWMA charts for the dispersion. It is...

Persistent link: https://www.econbiz.de/10012780188

Multivariate Statistical Process Control Charts and the Problem of Interpretation : A Short Overview and Some Applications in Industry

Bersimis, Sotiris - 2006

developing sections of statistical process control. Nowadays, in industry, there are many situations in which the simultaneous … which several related variables are of interest are collectively known as Multivariate Statistical Process Control (MSPC … multivariate statistical process control via control charting. In the second part we present the most useful procedures for …

Persistent link: https://www.econbiz.de/10012780593

Control Charts for the Lognormal Distribution

Maravelakis, Petros; Panaretos, John; Psarakis, Stelios - 2006

Control Charts are the main tools of Statistical Process Control. They are used for deciding whether a process is …

Persistent link: https://www.econbiz.de/10014054272

Effect of Estimation on the Univariate Control Charts for Process Dispersion

Maravelakis, Petros; Panaretos, John; Psarakis, Stelios - 2006

Control charts are extensively used in many real world applications. Since process parameters are rarely known common practice is to estimate them. Then, the control limits are modified and become actually random variables. In this paper, we deal with the univariate control charts for dispersion...

Persistent link: https://www.econbiz.de/10014054283

The causes of never events in hospitals

Gitlow, Howard; “Amy” Zuo, Qun; Ullmann, Steven G.; … - In: International Journal of Lean Six Sigma 4 (2013) 3, pp. 338-344

Purpose – The purpose of this paper is to posit that it is possible to identify contributing factors for “never events,” preventable adverse events in the healthcare setting, and to develop “best practices” to prevent them. Design/methodology/approach – This paper focuses on three...

Persistent link: https://www.econbiz.de/10014782635

A case of implementing SPC in a pulp mill

Rantamäki, Jukka; Tiainen, Eeva‐Liisa; Kässi, Tuomo - In: International Journal of Lean Six Sigma 4 (2013) 3, pp. 321-337

paper is to contribute to the body of knowledge on applying statistical process control (SPC) methods in a pulp mill …

Persistent link: https://www.econbiz.de/10014782700

Scaled critical factor index for optimal resource allocation in service and lean construction

Belay, Alemu Moges; Takala, Josu; Toshev, Rayko; … - In: International Journal of Sustainable Economy 5 (2013) 3, pp. 286-306

and the response rate was 48%. Different statistical process control charts were incorporated in the analysis to avoid …

Persistent link: https://www.econbiz.de/10011130047

A CUSUM scheme for event monitoring

Qu, Liang; Wu, Zhang; Khoo, Michael B.C.; Castagliola, … - In: International Journal of Production Economics 145 (2013) 1, pp. 268-280

This article presents a single CUSUM scheme (called the GCUSUM chart) for simultaneously monitoring the time interval T and magnitude X of an event. For example, a traffic accident may be considered as an event, and the total loss in dollars in each case is the event magnitude. Since the GCUSUM...

Persistent link: https://www.econbiz.de/10010869111

Joint optimization of X¯ control chart and preventive maintenance policies: A discrete-time Markov chain approach

Xiang, Yisha - In: European Journal of Operational Research 229 (2013) 2, pp. 382-390

Statistical process control and maintenance planning have long been treated as two separate problems. The …. Information obtained in the course of statistical process control signals the need for possible maintenance actions, and thus … deterioration and improve product quality in conjunction with statistical process control. This paper presents an integrated model …

Persistent link: https://www.econbiz.de/10011052789