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Automatic Identification of Metastable Conformations via Self-Organized Neural Networks

  • T. Galliat
  • P. Deuflhard
  • R. Roitzsch
  • F. Cordes
Part of the Lecture Notes in Computational Science and Engineering book series (LNCSE, volume 24)

Abstract

As has been shown recently, the identification of metastable chemical conformations leads to a Perron cluster eigenvalue problem for a reversible Markov operator. Naive discretization of this operator would suffer from combinatorial explosion. As a first remedy, a pre-identification of essential degrees of freedom out of the set of torsion angles had been applied up to now. The present paper suggests a different approach based on neural networks: its idea is to discretize the Markov operator via self-organizing box maps. The thus obtained box decomposition then serves as a prerequisite for the subsequent Perron cluster analysis. Moreover, this approach also permits exploitation of additional structure within embedded simulations. As it turns out, the new method is fully automatic and efficient also in the treatment of biomolecules. This is exemplified by numerical results.

Keywords

Biochemical conformations cluster analysis molecular dynamics Hybrid Monte-Carlo methods Markov operator Perron cluster analysis Self-Organizing Maps 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • T. Galliat
    • 1
  • P. Deuflhard
    • 1
    • 2
  • R. Roitzsch
    • 1
  • F. Cordes
    • 1
  1. 1.Konrad-Zuse-Zentrum für Informationstechnik BerlinBerlinGermany
  2. 2.Fachbereich Mathematik und InformatikFreie Universität BerlinBerlinGermany

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