A new model updating method is presented here with emphasis on identi"cation of joint sti!nesses. A so-called reduced-order characteristic polynomial (ROCP) is "rst de"ned in terms of the measured natural frequency, the partial modal properties predicted from a #awed FEM model and the model paramete
A new model updating method for damped structural systems
โ Scribed by Jiashang Jiang; Yongxin Yuan
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 95 KB
- Volume
- 32
- Category
- Article
- ISSN
- 0170-4214
- DOI
- 10.1002/mma.1129
No coin nor oath required. For personal study only.
โฆ Synopsis
Abstract
In this paper, the following two are considered:
Problem IQEP
Given M~a~โSR^nรn^, ฮ=diag{ฮป~1~, โฆ, ฮป~p~}โC^pรp^, X=[x~1~, โฆ, x~p~]โC^nรp^, and both ฮ and X are closed under complex conjugation in the sense that \documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}$\lambda_{2j} = \bar{\lambda}_{2j-1} \in {\mathbf{C}}$\end{document}, x~2__j__~=xฬ~2__j__โ1~โC^n^ for j = 1,โฆ,l, and ฮป~k~โR, x~k~โR^n^ for k=2__l__+1,โฆ,p, find realโvalued symmetric (2__r__+1)โdiagonal matrices D and K such that โฅM~a~__X__ฮ^2^+__DX__ฮ+KXโฅ=min.
Problem II
Given realโvalued symmetric (2__r__+1)โdiagonal matrices D~a~, K~a~โR^nรn^, find
\documentclass{article}\footskip=0pc\usepackage{amssymb}\usepackage[mathscr]{euscript}\pagestyle{empty}\begin{document}$(\hat{D},\hat{K}) \in {\mathscr{S}}_{DK}$\end{document} such that \documentclass{article}\usepackage{amssymb}\usepackage[mathscr]{euscript}\footskip=0pc\pagestyle{empty}\begin{document}$|\hat{D}-D_a |^2+ | \hat{K}-K_a |^2=\rm{inf}_{(D,K) \in {\mathscr{S}}_{DK}}(|D-D_a|^2+|K-K_a|^2)$\end{document}, where ๐ฎ~DK~ is the solution set of IQEP.
By applying the Kronecker product and the stretching function of matrices, the general form of the solution of Problem IQEP is presented. The expression of the unique solution of Problem II is derived. A numerical algorithm for solving Problem II is provided. Copyright ยฉ 2009 John Wiley & Sons, Ltd.
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