Paper Info
Title
Functional Control Charts and Health Monitoring of Steam Sterilizers.
Abstract
In this paper, motivated by a multiple profile monitoring problem, we introduce general functional exponentially weighted moving average (EWMA) control charts. When functional data to be monitored are smooth enough to be representable by a finite dimensional basis, a particular version of these functional EWMAs is shown to be a multivariate EWMA applied to basis coefficients. Hence, it is called f-EWMA for monitoring single profiles and f-MEWMA for multiple profiles. The use of f-MEWMAis illustrated in connection to health monitoring of a steam sterilizer during its life cycle. Indeed, each sterilization run gives several profiles related to machine health, and degradation of the steam sterilizer during its life cycle modifies profile curvature in an unpredictableway. Hence, a control chart capable to monitor multiple sterilization profiles during the sterilizer life cycle is needed. The f-EWMAthresholds or control limits have been computed usingMonte Carlo simulations. Moreover, the f-EWMA performance has been assessed using experimental data generated in laboratory according to anomalies considered relevant to the sterilizer maintenance program. Consequently, the average run length for these anomalies has been computed applying Monte Carlo simulation to experimental results. Copyright (C) 2016 JohnWiley & Sons, Ltd.
Year
DOI
Venue
2016
10.1002/qre.2035
QUALITY AND RELIABILITY ENGINEERING INTERNATIONAL
Keywords
Field
DocType
statistical surveillance,profile monitoring,statistical process control,curvature changes,medical equipment monitoring
Control limits,Monte Carlo method,Curvature,Experimental data,Multivariate statistics,EWMA chart,Control chart,Statistical process control,Engineering,Statistics
Journal
Volume
Issue
ISSN
32
6
0748-8017
Citations 
PageRank 
References 
1
0.36
6
Authors
3
Name
Order
Citations
PageRank
Alessandro Fassò1102.88
Maurizio Toccu262.70
Marino Magno310.36