In Operational Modal Analysis, the modal parameters (natural frequencies, damping ratios and mode shapes), obtained from Stochastic Subspace Identification of structures, are subject to statistical uncertainty from ambient vibration measurements. It is hence neccessary to evaluate the confidence intervals of these obtained results. This paper will propose an algorithm that can efficiently estim...

An ambient modal framework for inertia estimation using synchrophasor data is proposed in this letter. Specifically, an analytical formulation developed the of based on frequency and damping ratio modes extracted from data. advantage that it can rely synchronized under non-disturbed conditions online tracking inertia. Ultimately, numerical simulation studies physical experiments demonstrate fea...

Ambient vibration test is one of the most applicable and reliable methods among vibration tests due to recently fast evolvement of measurement, sensor technologies and data processing, and economical benefit as well. Modal identification methods of the ambient vibration structures are output-only identification techniques which have commonly been branched into either the frequency domain or the...

In some qualification such as damage detection, a more detailed representation including mass, stiffness, and damping property matrices plays a more pivotal role than an equivalent state-space model. In practice, estimating the modal parameters of the dominant modes in the signal records is superior to directly identifying the mass, stiffness, and damping matrices. In this paper, a novel techni...

Cylindrical shells are used in a variety of applications. In some of these applications it is necessary to limit the vibrations of lightly-damped shells by applying a damping treatment that does not significantly increase the weight. This paper explores the use of partial coating of a cylindrical shell with a constrained viscoelastic layer for obtaining optimal damping. The placement of damping...

We present a four-body semileptonic charm decay D → Kπμν analysis in the range of 0.65 GeV/c < mKπ < 1.5 GeV/c . We observe a low mass scalar contribution of 5.30 ± 0.74 0.99 − 0.96% with respect to the total D →Kπμν decay, compatible with the phase shift found by the LASS elastic scattering experiment. For the K(892) resonance, we obtain a mass of 895.41 ± 0.32 − 0.43 MeV/c , a width of 47.79 ...

Modal control and spatial filtering technologies for vibration and/or structural acoustics radiation mitigation may be implemented through the use of distributed modal piezoelectric transducers with properly shaped electrodes which, in order to increase the robustness and stability of the controlled structural system, turn undesirable mode’s contributions unobservable and uncontrollable over th...

Abstract—One good analysis method in seismic response analysis is direct time integration, which widely adopts Rayleigh damping. An approach is presented for selection of Rayleigh damping coefficients to be used in seismic analyses to produce a response that is consistent with Modal damping response. In the presented approach, the expression of the error of peak response, acquired through compl...

The development of a modal model, from either frequency response measurements or from a finite element model, is useful for simulation and design studies. One of these studies is structural dynamics modification. This is a mathematical process which uses modal data (frequency, damping and mode shapes) to determine the effects of changes in the system characteristics due to physical structural c...

Analysis of an aeroelastic bridge system consisting of the fundamental vertical and torsional modes of vibration offers an expeditious assessment of bridge flutter performance. It also produces valuable insight into the multimode coupled bridge response to strong winds. This paper presents closed-form formulations for estimating the modal frequencies, damping ratios, and coupled motions of the ...