Modeling - A Game with Timescales

Prof. Dr. Dipl.-Ing. Heinz A. Preisig

   Zeit: Dienstag, 15. 05. 2001, 16:00
   Ort: Hörsaal V 9.31 Pfaffenwaldring 9, Universitätsbereich Stuttgart-Vaihingen

Abstract:

A few years ago, we put ourselves the task to wrap modeling of processes, as relevant to the process industry, into a set of programs. Whilst the formulation of the task was quite straightforward, the realisation turned out to be nontrivial. To my personal surprise one of the main problems lays in the inertia of the community and the belief that everybody knows on how to write process models. Colleagues would take frequently two extreme positions, on the one hand the task is seen as trivial and not delivering anything new, whilst the other party views it a too complex and multifaceted as to be captured in a programmatic system. Both parties, most, here including the "believers", would consider the preparative work too abstract and esoteric. Over the years, we have put a great deal of effort into analysing the bag of tricks, which is commonly passed on in the educational system. This analysis yielded a number of structures, which indeed act as integrating factors for many of the elements in the bag. The process of identifying such structures has not been without a good measure of simple sweat, but delivered a number of interesting connections and certainly keeps on rising questions.

In this representation, I should like to bring a few problems closer to the participants, problems all of which have a certain characteristics, namely the property of multiple timescales. The presentation is a collage of examples. Each example focuses on a particular modeling problem. Seen from a distance, the problems are quite different, at least if the integrating factor of different timescales is ignored. The presentation generates a view, which extends to a family of methods that are suitable for a programmatic approach thereby providing a deep insight in illuminated aspects of different timescales in process and the associated modeling problems.

Biographical Sketch:

Dr. Heinz A. Preisig is Professor of Systems and Control at the Eindhoven University of Technology (Netherlands), which he joined in 1995. From 1995 to 2000 he had a dual appointment with the faculties Chemical Engineering and Applied Physics. Since 2000 he is with the Electrical Engineering department. Dr. Preisig received his Dipl.-Ing. HTL/Chemist HTL degree from the Technikum Winterthur (1974), his Dipl.-Ing. in chemical engineering (1978) and his Ph.D. (1984) both from the Swiss Federal Institute of Technology (ETH), Zurich. From 1984 to 1989 he has been an assistant professor in chemical engineering at the Texas A&M University (USA). Furthermore he has been a senior lecturer at the school of Chemical Engineering and Industrial Chemistry at the University of New South Wales, Sydney, Australia and is a regular visiting professor at the National University of Singapore. Dr. Preisig's research interests include linear and nonlinear model predictive control, process identification, and modelling and control of hybrid systems. He is interested in applications to sequential control and fault diagnosis and detection. Furthermore time-scale analysis (wavelets, singular pertubation) and modelling of macroscopic systems with an emphasis on system representation (and model reduction) belong to his research interests.