Rheologica Acta

, Volume 32, Issue 1, pp 65–73 | Cite as

A nonlinear regularization method for the calculation of relaxation spectra

  • J. Honerkamp
  • J. Weese
Original Contributions


It is well known that the relaxation spectrum characterizing the linear viscoelastic properties of a polymer melt or solution is not directly accessible by an experiment. Therefore, it must be calculated from data for a material function. With Tikhonov regularization the relaxation spectrum in the terminal and plateau region can be calculated from data for a material function in the corresponding region. Serious difficulties arise however, if the spectrum should be determined in a larger range. These difficulties are caused by the considerably different contributions at short and long relaxation times. We show that these difficulties can be avoided by a nonlinear regularization method.

Key words

Relaxation spectrum Tikhonov regularization nonlinear regularization 


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Copyright information

© Steinkopff-Verlag 1993

Authors and Affiliations

  • J. Honerkamp
    • 1
    • 2
  • J. Weese
    • 1
  1. 1.University of FreiburgGermany
  2. 2.Fakultät für PhysikUniversität FreiburgFreiburg i. Br.Germany

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