Modeling of bioprocesses for engineering applications is a very difficult a
nd time consuming task, due to their complex nonlinear dynamic behavior. In
the last years several propositions for hybrid models, and especially seri
al approaches, were published and discussed, in order to combine analytical
prior knowledge with the learning capabilities of Artificial Neural Networ
ks (ANN). These approaches often require synchronous and equi-distant sampl
ed training data. However, in practice concentrations are mostly off-line m
easured, rare, and asynchronous. In this paper a new training method especi
ally suited for very few asynchronously sampled data is presented and appli
ed for modeling animal cell cultures. The achieved model is able to predict
the concentrations of the reaction components inside a stirred tank biorea
ctor.