title: Uneven batch data alignment with application to the control of batch end-product quality.
abstract: Batch processes are commonly characterized by uneven trajectories due to the existence of batch-to-batch variations. The batch end-product quality is usually measured at the end of these uneven trajectories. It is necessary to align the time differences for both the measured trajectories and the batch end-product quality in order to implement statistical process monitoring and control schemes. Apart from synchronizing trajectories with variable lengths using an indicator variable or dynamic time warping, this paper proposes a novel approach to align uneven batch data by identifying short-window PCA&PLS models at first and then applying these identified models to extend shorter trajectories and predict future batch end-product quality. Furthermore, uneven batch data can also be aligned to be a specified batch length using moving window estimation. The proposed approach and its application to the control of batch end-product quality are demonstrated with a simulated example of fed-batch fermentation for penicillin production.
authors.affiliation: Control Systems Center, School of Electrical and Electronic Engineering, The University of Manchester, Manchester, UK. Electronic address: jian.wan@hotmail.com.
authors.forename: Jian
authors.initials: J
authors.lastname: Wan
authors.affiliation: Control Systems Center, School of Electrical and Electronic Engineering, The University of Manchester, Manchester, UK. Electronic address: ognjen.marjanovic@manchester.ac.uk.
authors.forename: Ognjen
authors.initials: O
authors.lastname: Marjanovic
authors.affiliation: Control Systems Center, School of Electrical and Electronic Engineering, The University of Manchester, Manchester, UK. Electronic address: barry.lennox@manchester.ac.uk.
authors.forename: Barry
authors.initials: B
authors.lastname: Lennox
mesh_terms: D000465:Algorithms; D018533:Biomass; D019149:Bioreactors; D002626:Chemistry, Pharmaceutical / Q000295:instrumentation; D004345:Drug Industry / Q000295:instrumentation*; D005285:Fermentation; D010100:Oxygen / Q000737:chemistry; D010406:Penicillins / Q000737:chemistry; D011786:Quality Control
chemical_list: D010406:Penicillins; D010100:Oxygen
keywords: Alignment; End-product quality control; Partial least squares; Principal component analysis; Variable batch lengths