### Skapa referens, olika format (klipp och klistra)

**Harvard**

Johansson, A. och Abrahamsson, T. (2011) *Selecting Appropriate Analytical Mode Basis for SEREP-expansion of Experimental Modes*.

** BibTeX **

@conference{

Johansson2011,

author={Johansson, Anders T and Abrahamsson, Thomas},

title={Selecting Appropriate Analytical Mode Basis for SEREP-expansion of Experimental Modes},

booktitle={Proceedings of the 29th IMAC, A Conference on Structural Dynamics, 2011},

isbn={978-1-4419-9298-7},

abstract={Since being introduced in 1986, the System Equivalent Reduction Expansion
Process (SEREP) has been used to expand experimental eigenvector elements
to the number of degrees-of-freedom of an associated FE-model. In fact, expansion
for interpolation and extrapolation was its original purpose. Since then, studies of
SEREP and other reduction/expansion methods have been abundant. A remarkable
number of these have concentrated on the selection of master degrees of freedom
for model reduction. Few have however considered the modal basis best used when
SEREP is used for expansion.
Expanded experimental modes are expected to correlate well with their analytical
siblings. However, we argue that the degree of global correlation should only be in
parity with the local correlation between the analytical and experimental modes at
locations where measurements are made. Since SEREP is a method which basically
approximates a measured mode by a linear combination of analytical modes, perfect
agreement between the expanded experimental and analytical modes is easily
achieved, e.g. by simply using only one single mode for expansion. Of course, in
this way the expanded mode normally has very little in common with the measured
mode. On the other hand, using too many modes may result in something similar
to the well known problem of fitting a high-order polynomial to noisy data: Perfect
agreement at measurement locations is achieved at the expense of unrealistic
deviations and large curvatures between these. To make sure that the experimental
mode has been expanded in a manner faithful to the actual measurements, it is therefore
reasonable to use a correlation based criterion in the selection of the expansion
basis. Such a criterion is presented in the present paper.},

year={2011},

keywords={SEREP, model expansion, modal analysis},

}

** RefWorks **

RT Conference Proceedings

SR Print

ID 137241

A1 Johansson, Anders T

A1 Abrahamsson, Thomas

T1 Selecting Appropriate Analytical Mode Basis for SEREP-expansion of Experimental Modes

YR 2011

T2 Proceedings of the 29th IMAC, A Conference on Structural Dynamics, 2011

SN 978-1-4419-9298-7

AB Since being introduced in 1986, the System Equivalent Reduction Expansion
Process (SEREP) has been used to expand experimental eigenvector elements
to the number of degrees-of-freedom of an associated FE-model. In fact, expansion
for interpolation and extrapolation was its original purpose. Since then, studies of
SEREP and other reduction/expansion methods have been abundant. A remarkable
number of these have concentrated on the selection of master degrees of freedom
for model reduction. Few have however considered the modal basis best used when
SEREP is used for expansion.
Expanded experimental modes are expected to correlate well with their analytical
siblings. However, we argue that the degree of global correlation should only be in
parity with the local correlation between the analytical and experimental modes at
locations where measurements are made. Since SEREP is a method which basically
approximates a measured mode by a linear combination of analytical modes, perfect
agreement between the expanded experimental and analytical modes is easily
achieved, e.g. by simply using only one single mode for expansion. Of course, in
this way the expanded mode normally has very little in common with the measured
mode. On the other hand, using too many modes may result in something similar
to the well known problem of fitting a high-order polynomial to noisy data: Perfect
agreement at measurement locations is achieved at the expense of unrealistic
deviations and large curvatures between these. To make sure that the experimental
mode has been expanded in a manner faithful to the actual measurements, it is therefore
reasonable to use a correlation based criterion in the selection of the expansion
basis. Such a criterion is presented in the present paper.

LA eng

OL 30