Figure 4: Offline optimisation of the two fed-batch operation processes with the three extra practical constraints. Lines are hybrid model prediction results, points are computational experimental verification. (a), (c), and (e): control actions of this fed-batch process are predicted by the hybrid model. (b), (d), and (f): control actions of this fed-batch process are predicted by the original kinetic model (theoretical maximum lutein production), and the hybrid model is used to predict the process behaviour.