TY - JOUR
T1 - Monitoring nonlinear profile data using support vector regression method
AU - Li, Chung I.
AU - Pan, Jeh Nan
AU - Liao, Chun Han
N1 - Funding Information:
We are grateful to the two anonymous reviewers for their helpful comments. The second author would like to gratefully acknowledge financial support (MOST 106‐2410‐H‐ 006‐007) from the Ministry of Science and Technology of Taiwan, ROC.
Funding Information:
Ministry of Science and Technology of Taiwan, ROC, Grant/Award Number: MOST 106-2410-H-006-007
Publisher Copyright:
© 2018 John Wiley & Sons, Ltd.
PY - 2019/2/1
Y1 - 2019/2/1
N2 - In today's manufacturing industries, if the quality characteristic of a product or a process is assumed to be represented by a functional relationship between the response variable and one or more explanatory variables, then the data generated from such a relationship are called profile data. Generally speaking, the functional relationship of the profile data rarely occurs in linear form, and the real data usually do not follow normal distribution. Thus, in this paper, the functional relationship of profile data is described via a nonparametric regression model and a nonparametric exponentially weighted moving average (EWMA) control chart is developed for detecting the process shifts for nonlinear profile data in the Phase II monitoring. We first fit the nonlinear profile data via a support vector regression model and use the fitted values to calculate the five metrics. Then, the nonparametric EWMA control chart with the five metrics can be constructed accordingly. Moreover, a simulation study is conducted to evaluate the detecting performance of the new control chart under various process shifts using the out-of-control average run length. Finally, a realistic nonlinear profile example is used to demonstrate the usefulness of our proposed nonparametric EWMA control chart and its monitoring schemes. It is expected that the proposed nonparametric EWMA control chart can enhance the monitoring efficiency for nonlinear profile data in the phase II study.
AB - In today's manufacturing industries, if the quality characteristic of a product or a process is assumed to be represented by a functional relationship between the response variable and one or more explanatory variables, then the data generated from such a relationship are called profile data. Generally speaking, the functional relationship of the profile data rarely occurs in linear form, and the real data usually do not follow normal distribution. Thus, in this paper, the functional relationship of profile data is described via a nonparametric regression model and a nonparametric exponentially weighted moving average (EWMA) control chart is developed for detecting the process shifts for nonlinear profile data in the Phase II monitoring. We first fit the nonlinear profile data via a support vector regression model and use the fitted values to calculate the five metrics. Then, the nonparametric EWMA control chart with the five metrics can be constructed accordingly. Moreover, a simulation study is conducted to evaluate the detecting performance of the new control chart under various process shifts using the out-of-control average run length. Finally, a realistic nonlinear profile example is used to demonstrate the usefulness of our proposed nonparametric EWMA control chart and its monitoring schemes. It is expected that the proposed nonparametric EWMA control chart can enhance the monitoring efficiency for nonlinear profile data in the phase II study.
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U2 - 10.1002/qre.2385
DO - 10.1002/qre.2385
M3 - Article
AN - SCOPUS:85053674126
SN - 0748-8017
VL - 35
SP - 127
EP - 135
JO - Quality and Reliability Engineering International
JF - Quality and Reliability Engineering International
IS - 1
ER -