0141-0296/$ see front matter 2012 Elsevier Ltd. A http://dx.doi.org/10.1016/j.engstruct.2012.03.013 ⇑ Corresponding author. Tel.: +351 22 508 1901; fa E-mail addresses: [email protected] (D. Ribeiro), r [email protected] (R. Delgado), [email protected] uni-weimar.de (V. Zabel). This article describes the calibration of the numerical model of a bowstring-arch railway bridge based on modal param...

Through the bright spot detection of small target image in natural scene, which is capable of appealing people's visual attention for rapid detection and identification of targets. Notable highlights model of small target image in natural scenes is prone to bring visual error with the difference between centre and surrounding of the background image, and visual saliency detection is ineffective...

This paper presents a robust watermarking scheme for 3D subdivision surfaces. Our proposal is based on a frequency domain decomposition of the subdivision control mesh and on spectral coefficients modulation. The compactness of the cover object (the coarse control mesh) has led us to optimize the trade-off between watermarking redundancy (which insures robustness) and imperceptibility by introd...

Recently, a variety of wireless structural health monitoring systems have been demonstrated as viable substitutes for traditional high-cost tethered monitoring systems. In this study, a prototype wireless sensing system is deployed on the Voigt Bridge (La Jolla, CA) and a historical theatre (Detroit, MI) to validate its performance against cabled monitoring systems. Acceleration time history re...

A new method of direction-of-arrival (DOA) estimation for multiple broadband farfield signals is presented. The technique uses a beamspace preprocessing structure based on frequency-invariant beamforming. Specifically, a set of beam-shaping filters focus the received array data in the time domain, thereby avoiding the need for frequency decomposition. Hence, the proposed method is conceptually ...

In this paper two modal identification approaches appropriate for use in a distributed computing environment are applied to a full-scale, complex structure. The natural excitation technique (NExT) is used in conjunction with a condensed eigensystem realization algorithm (ERA), and the frequency domain decomposition with peak-picking (FDD-PP) are both applied to sensor data acquired from a 57.5-...

most geologic changes have a seismic response but sometimes this is expressed only in certain spectral ranges hidden within the broadband data. spectral decomposition is one of the methods which can be utilized to help interpreting such cases. there are several time-frequency methods including: short-time fourier transform (stft), continuous wavelet transform (cwt), wigner-ville distribution (w...

Moving vehicle’s driver’s Fatigueness is of prime concern for long and safe drive. Fatigueness can be estimated by observing the facial expression. The said problem may be thought of analysis of driver’s facial expression in wavelet domain using entropy of low frequency and high frequency sub band of the facial image. Further, the video movie of the driver may be decomposed into images as frame...

In this article, we address the problem of singular value decomposition of polynomial matrices and eigenvalue decomposition of para-Hermitian matrices. Discrete Fourier transform enables us to propose a new algorithm based on uniform sampling of polynomial matrices in frequency domain. This formulation of polynomial matrix decomposition allows for controlling spectral properties of the decompos...

Frequency-transformed EEG resting data has been widely used to describe normal and abnormal brain functional states as function of the spectral power in different frequency bands. This has yielded a series of clinically relevant findings. However, by transforming the EEG into the frequency domain, the initially excellent time resolution of time-domain EEG is lost. The topographic time-frequency...