Open AccessHybrid filtering to rescue stable oscillations from noise‐induced chaos in continuous cultures of budding yeast
Author(s) -
Patnaik Pratap R.
Publication year - 2006
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/j.1567-1364.2005.00009.x
Subject(s) - noise (video) , dilution , budding yeast , filter (signal processing) , biology , biological system , control theory (sociology) , chaotic , bioreactor , yeast , saccharomyces cerevisiae , physics , computer science , artificial intelligence , control (management) , biochemistry , thermodynamics , botany , image (mathematics) , computer vision
In large‐scale fermentations with oscillating microbial cultures, noise is commonly present in the feed stream(s). As this can destabilize the oscillations and even generate chaotic behavior, noise filters are employed. Here three types of filters were compared by applying them to a noise‐affected continuous culture of Saccharomyces cerevisiae with chaotic oscillations. The aim was to restore the original noise‐free stable oscillations. An extended Kalman filter was found to be the least efficient, a neural filter was better and a combined hybrid filter was the best. In addition, better filtering of noise was achieved in the dilution rate than in the oxygen mass transfer coefficient. These results suggest the use of hybrid filters with the dilution rate as the manipulated variable for bioreactor control.