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STFT Nonlinear Identification Tool

The tool allows for the instantaneous estimation of parameters of nonlinear systems. It relies on the Short Time Fourier Transform (STFT) time-frequency approach.

Launch Tool

This tool is distrubuted as a downloadable file. To download, please visit the 'Docs and Attachments' section, or click the button below.


Version 1.1 - published on 20 Feb 2014

Open source: license | download

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The proposed tool for the instantaneous identification of nonlinear systems relies on a time-frequency approach. The entailing formulation determines model parameters that minimize an error function between time-frequency representations of measured and simulated signals, respectively. In greater detail, the representation adopted here is the Short Time Fourier Transform (STFT). The tuning of a simple single degree of freedom oscillator endowed with a Bouc-Wen hysteretic spring is provided as application example. In order to start the algorithm:

-           Download and extract the archive

-           Enter the extracted folder

-           Run the MatLAB script “Script_TF_v1.m”.

The implementation of a generic state space model is straightforward.

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Oreste S. Bursi, Giuseppe Abbiati, Rosario Ceravolo


Bursi, O. S., Ceravolo, R., Erlicher, S., & Zanotti Fragonara, L. (2012). Identification of the hysteretic behaviour of a partial-strength steel-concrete moment-resisting frame structure subject to pseudodynamic tests. Earthquake Engineering & Structural Dynamics, 41(14), 1883–1903. doi:10.1002/eqe.2163

Cite this work

Researchers should cite this work as follows:

  • oreste s. bursi; giuseppe abbiati; Rosario Ceravolo (2013), "STFT Nonlinear Identification Tool,"

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