کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
559498 | 1451887 | 2012 | 12 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: A model for quantifying uncertainty in the estimation of noise-contaminated measurements of transmissibility A model for quantifying uncertainty in the estimation of noise-contaminated measurements of transmissibility](/preview/png/559498.png)
System identification in the frequency domain is a very important process in many aspects of engineering. Among many forms of frequency domain system identification such as frequency response function analysis and modal decomposition, transmissibility (output-to-output relationship) estimation has been regarded as one of the most practical tools for its clear physical interpretation, its compatibility with output-only data, and its sensitivity to local changes of structural parameters. Due to operational and environmental variability in any real system, quantization and estimation error, and extraneous measurement noise, the computation of transmissibility may contain a significant level of uncertainty and variability, and these sources propagate to degrade system identification quality and in some cases to system mischaracterization. In this paper, the uncertainty of the magnitude of a transmissibility estimator via output auto-power density spectra is quantified, an exact probability density function for the estimates is derived analytically via a Chi-square bivariate approach, and it is validated with Monte Carlo simulation. Validation shows very consistent results between the observed histogram and predicted distribution for different estimation and noise conditions.
► We model sources of uncertainty for a transmissibility amplitude estimator.
► The model includes both measurement error and extraneous noise.
► The model was validated on a vibrating beam structure.
► Uncertainty is exactly quantified and predicted even for low signal-to-noise situations.
Journal: Mechanical Systems and Signal Processing - Volume 28, April 2012, Pages 470–481