Process trends formal representation

The extraction, though, of the so-called pivotal features from operating data, encounters the same impediments that we discussed earlier on the subject of process trends representation (1) localization in time of operating features and (2) the multiscale content of operating trends. It is clear, therefore, that any systematic and sound methodology for the identification of patterns between process data and operating conditions can be built only on formal and sound descriptions of process trends. 

Cheung, J. T.-Y., Representation and extraction of trends from process data. Sc.D. Thesis, Massachusetts Institute of Technology, Dept. Chem. Eng., Cambridge, MA (1992). Cheung, J. T.-Y., and Stephanopoulos, G., Representation of process trends. Part I. A formal representation framework. Comput. Chem. Eng. 14, 495-510 (1990). 

JTY Cheung and G. Stephanopoulos. Representation of process trends, Part I. A formal representation framework. Comp. Chem. Engg., 14 495-510, 1990. 

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