Applied Rheology: Publications
Arsia Takeh, Sachin Shanbhag
A Computer Program to Extract the Continuous and Discrete Relaxation Spectra from Dynamic Viscoelastic Measurements

Appl. Rheol. 23:2 (2013) 24628 (10 pages)

Abstract: We describe and implement an efficient, open-source, multi-platform computer program ReSpect to infer the continuous and discrete relaxation spectra from dynamic moduli measurements obtained by small-angle oscillatory shear experiments. We employ nonlinear Tikhonov regularization and the Levenberg-Marquardt method to extract the continuous relaxation spectrum. To obtain the discrete relaxation spectrum, we introduce a novel algorithm that exploits the continuous spectrum to position the modes. It uses a simple criterion which balances accuracy and conditioning of the resulting least-squares problem to determine a parsimonious number of modes. The end result is an easy-to-use, and easy-to-extend program, which can be used from the command-line or from a graphical user interface to override some of the default algorithmic choices. © 2013 Applied Rheology.

Related Software ReSpect available for free download at mathworks.

© 2013 Applied Rheology.

DOI 10.3933/ApplRheol-23-24628

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Appl Rheol 23 (2013) issues:


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