---
res:
  bibo_abstract:
  - In this contribution, we address the estimation of the frequency-dependent elastic
    parameters of polymers in the ultrasound range, which is formulated as an inverse
    problem. This inverse problem is implemented as a nonlinear regression-type optimization
    problem, in which the simulation signals are fitted to the measurement signals.
    These signals consist of displacement responses in waveguides, focusing on hollow
    cylindrical geometries to enhance the simulation efficiency. To accelerate the
    optimization and reduce the number of model evaluations and wait times, we propose
    two novel methods. First, we introduce an adaptation of the Levenberg–Marquardt
    method derived from a geometrical interpretation of the least-squares optimization
    problem. Second, we introduce an improved objective function based on the autocorrelated
    envelopes of the measurement and simulation signals. Given that this study primarily
    relies on simulation data to quantify optimization convergence, we aggregate the
    expected ranges of realistic material parameters and derive their distributions
    to ensure the reproducibility of optimizations with proper measurements. We demonstrate
    the effectiveness of our objective function modification and step adaptation for
    various materials with isotropic material symmetry by comparing them with the
    Broyden–Fletcher–Goldfarb–Shanno method. In all cases, our method reduces the
    total number of model evaluations, thereby shortening the time to identify the
    material parameters.@eng
  bibo_authorlist:
  - foaf_Person:
      foaf_givenName: Dominik
      foaf_name: Itner, Dominik
      foaf_surname: Itner
  - foaf_Person:
      foaf_givenName: Dmitrij
      foaf_name: Dreiling, Dmitrij
      foaf_surname: Dreiling
      foaf_workInfoHomepage: http://www.librecat.org/personId=32616
  - foaf_Person:
      foaf_givenName: Hauke
      foaf_name: Gravenkamp, Hauke
      foaf_surname: Gravenkamp
  - foaf_Person:
      foaf_givenName: Bernd
      foaf_name: Henning, Bernd
      foaf_surname: Henning
      foaf_workInfoHomepage: http://www.librecat.org/personId=213
  - foaf_Person:
      foaf_givenName: Carolin
      foaf_name: Birk, Carolin
      foaf_surname: Birk
  bibo_doi: https://doi.org/10.1016/j.ymssp.2026.113904
  bibo_volume: 247
  dct_date: 2026^xs_gYear
  dct_isPartOf:
  - http://id.crossref.org/issn/0888-3270
  dct_language: eng
  dct_subject:
  - Material parameter estimation
  - Waveguide
  - Nonlinear optimization
  - Inverse problem
  - Least squares
  dct_title: A modified Levenberg–Marquardt method for estimating the elastic material
    parameters of polymer waveguides using residuals between autocorrelated frequency
    responses@
...