%A P R Patnaik %O Copyright of this article belongs to Canadian Society for Chemical Engineering. %J Canadian Journal of Chemical Engineering %T Neural and hybrid neural modelling and control of fed-batch fermentation for streptokinase: Comparative evaluation under nonideal conditions. %X Fermentations involving competition between two or more kinds of cells under nonideal conditions show complex profi les that are sensitive to the extra-cellular environment. These fermentations therefore require accurate and rapid on-line data acquisition and control. However, both on-line measurements and modelling are diffi cult and expensive for large bioreactors, thus limiting the usefulness of model-based control. While neural networks offer an alternative, they require extensive training and can be diffi cult to optimize for large arrays. Hybrid networks combining a few neural networks with some mathematical equations offer a good compromise. The possibility of using a hybrid model for simulation-cum-control has been examined here for the fed-batch production of streptokinase. Under noideal conditions, hybrid neural models outperformed both mathematical models and arrays of neural networks, thus suggesting their viability for large-scale fermentation monitoring and control. Les fermentations provoquant une comp?tition entre deux ou plusieurs sortes de cellules dans des conditions non id?ales montrent des profi ls complexes qui sont sensibles ? l?environnement extra-cellulaires. Ces fermentations n?cessitent donc une acquisition et un contr?le en continu des donn?es qui soient pr?cis et rapides. Toutefois, les mesures et la mod?lisation en continu sont diffi ciles et co?teuses pour les grands bior?acteurs, ce qui limite l?utilit? du contr?le bas? sur des mod?les. Les r?seaux neuronaux sont une autre possibilit?, mais ceux-ci n?cessitent un entra?nement pouss? et peuvent ?tre diffi ciles ? optimiser pour de grands dispositifs. Les r?seaux hybrides combinant r?seaux neuronaux et ?quations math?matiques offrent un bon compromis. La possibilit? d?utiliser un mod?le hybride pour la simulation et le contr?le a ?t? examin?e dans ce travail pour la production ? alimentation discontinue de streptokinase. Dans des conditions non id?ales, les mod?les neuronaux hybrides offrent une meilleure performance que les mod?les math?matiques ou les dispositifs de r?seaux neuronaux, et il pourrait donc s?av?rer viable pour la surveillance et le contr?le de fermentation ? grande ?chelle %N 3 %K streptokinase, fed-batch fermentation, nonideal conditions, hybrid neural network. %P 599-607 %V 82 %D 2004 %I wiley %L open954