Recently theta-adaptive neural networks (TANN) were developed for para
meter estimation for systems with nonlinear parametrization [1]. This
paper discusses the estimation problem when additional information is
available about the model structure. In particular, algorithms are pre
sented for recursive parameter estimation for systems with partial non
linear parametrization and for systems where the nonlinearities appear
in an additive manner in the regression equation. Training procedures
are developed for the neural networks which ensure the stability of t
he algorithms. It is shown how the training procedures can be modified
to ensure stability in the presence of a bounded disturbance. The com
plexity of the neural networks needed to perform the identification ta
sks is greatly reduced compared to the TANN algorithm proposed in [1].
Simulation results are presented which demonstrate the capabilities o
f the algorithms. (C) Elsevier Science Inc. 1998.