Journal of Process Control, Vol.75, 107-119, 2019
Improved process monitoring based on global-local manifold analysis and statistical local approach for industrial process
A new kind process monitoring method which based on global-local manifold analysis is proposed in this article. Firstly, this method models the global-local manifold structure of the process in the off-line stage, and then detects the changes in the global-local manifold structure when new observation samples are used for on-line monitoring. In addition, conventional algorithms that based on global-local manifold structure may lose accuracy when monitor the process since the Gaussian assumption is not easily satisfied. In this new method, a novel score variable which approximately follows Gaussian distribution regardless of the original is derived. Besides, the incorporation of statistical local approach also reveals conspicuous detection sensitivity. We also propose a visual fault diagnosis method based on the global-local manifold structure analysis. The proposed process monitoring method is well examined through a numerical example and the TE process benchmark. (C) 2019 Elsevier Ltd. All rights reserved.