Showing papers in "Journal of Sound and Vibration in 1998"

TL;DR: In this paper, a continuous cracked beam vibration theory is developed for the lateral vibration of cracked Euler-Bernoulli beams with single-edge or double-edge open cracks.

TL;DR: In this article, the authors relate the proper orthogonal modes, as applied in discrete vibration systems, to normal modes of vibration in systems with a known mass matrix in the case of undamped free vibration.

TL;DR: In this article, a method based on modal strain energy is presented for locating damage in a structure, which makes use of the change of modal energy in each structural element before and after the occurrence of damage.

TL;DR: In this paper, the authors extend the Multiple Damage Location Assurance Criterion (MDLAC) by introducing two methods of estimating the size of defects in a structure, which are illustrated using numerical data for two truss structures and validated experimentally using a three-beam test structure.

TL;DR: In this paper, a new dynamic modeling method was proposed to derive the equation of motion of a rotating cantilever beam, which can be directly used for the vibration analysis including the coupling effect, which could not be considered in the conventional modelling method.

TL;DR: Owing to the cross-sectional design of the majority of the reviewed studies, this epidemiologic evidence is not sufficient to outline a clear exposure–response relationship between WBV exposure and LBP disorders.

TL;DR: In this article, the authors examined the implications of various damping models for the interpretation of measured transfer functions, especially in the context of experimental modal analysis, and showed that in the case of a dissipation-matrix model, it is possible in principle to determine all the model parameters from measurements.

TL;DR: In this paper, Fourier series analysis and the Floquet theory are used to perform qualitative global analysis on bifurcation and stability of a rub-impact Jeffcott rotor. But the analysis is limited to two-dimensional, non-linear and periodic systems.

TL;DR: In this article, a perturbation technique for computing normal forms is presented, associated with the method of multiple scales, which can be used to systematically find a unique form for a given set of differential equations.

TL;DR: In this article, the dynamics of a non-smooth friction oscillator under self-and external excitation are investigated and the rich bifurcational behaviour predicted by numerical simulations is compared to experimental results.

TL;DR: In this paper, a ridge extraction procedure using the modulus of the wavelet transform is presented, which employs the slowly-varying, time-dependent amplitude and phase functions of the impulse response of the system.

TL;DR: In this paper, the vertical apparent mass of the seated human body was analyzed using a two-degree-of-freedom model and a single-degree of freedom model with rigid support structures.

TL;DR: In the one leg posture, coupled rotational motion of the whole upper-body about the hip joint may have contributed to the resonance observed in the apparent mass at low frequencies and the attenuation of vertical vibration transmission at high frequencies.

TL;DR: The work on vibration control of machines and structures incorporating viscoelastic materials in suitable arrangements, highlighted for situations involving vibration excitations over a broad frequency range, is highlighted in this paper.

TL;DR: In this paper, the effects of frequency and strain amplitude as well as temperature on the damping behavior of superelastic NiTi shape memory alloy wires were investigated. And the dissipated energy and the loss factor were analyzed.

TL;DR: In this paper, a friction contact model is proposed to characterize cyclic relative motions at the contact interface and hysteresis loops can be produced so as to characterize the equivalent damping and stiffness of the friction contact.

TL;DR: In this paper, a unified matrix polynomial approach (UMPA) is used to unify the presentation with respect to current algorithms such as the least-squares complex exponential (LSCE), the polyreference time domain (PTD), Ibrahim time domain, eigensystem realization algorithm (ERA), rational fraction polynomials (RFP), polyreference frequency domain (PFD), and the complex mode indication function (CMIF) methods.

TL;DR: It has been shown that compression in vibration analysis can be used not only for effective storage and transmission of the data but also for feature selection.

TL;DR: In this article, the effect of crack closure on the dynamic behavior of cantilever beams is studied and the bispectral analysis performed both on the model and the actual structure shows high sensitivity of the non-linear behaviour of the system to the presence of the fatigue crack in the structure.

TL;DR: In this article, a new spectral approach for identifying multi-degree-of-freedom non-linear systems is introduced which is based on a reverse path formulation as available in the literature for single-degree of freedom nonlinear systems.

TL;DR: In this paper, a novel electro-acoustic transducer that uses the electrostrictive response of a polymer film was proposed, where the active element is a thin silicone-rubber film, with graphite powder electrodes on each side, that forms an array of bubble-like radiating elements.

TL;DR: In this article, the authors investigated the optimization of frequency response functions as a means to diagnose damage using a minimum number of sensors, where the structural response characteristics vary with small changes in boundary conditions and the environment.

TL;DR: In this article, the authors studied parametric resonances when an elastic system is rotated around an annular disc with friction having a negative slope with velocity, and demonstrated that the effect of the in-plane system including the negative friction-velocity relationship is to introduce additional parametric resonance which are destabilised by the transverse damper, and to reduce the regions of instability of the other resonances.

TL;DR: In this paper, the effect of delayed feedback on oscillatory behavior was investigated for the classical van der Pol oscillator and it was shown how the presence of delay can change the amplitude of limit cycle oscillations, or suppress them altogether.

TL;DR: In this paper, the propagation of small disturbances in an annular duct with a mean vortical swirling flow is studied, and the disturbance velocity is split into a nearly-convected part and a nearlysonic part, obeying weakly coupled equations.

TL;DR: In this paper, the acoustic impedance of multiply perforated plates exposed to fully developed grazing gas flow in duct, both with and without a backing layer of porous material, is investigated.

TL;DR: In this paper, the vibration of a multi-span non-uniform beam subjected to a moving load is analyzed by using modified beam vibration functions as the assumed modes, which satisfy the zero deflection conditions at all the intermediate point supports as well as the boundary conditions at the two ends of the beam.

TL;DR: In this paper, a dynamic Green function approach is used to determine the response of a simply supported Bernoulli-Euler beam of finite length subject to a moving mass traversing its span.

TL;DR: In this article, the computer implementation of the new absolute nodal co-ordinate formulation and its use in the small and large deformation analysis of flexible multibody systems that consist of interconnected bodies are discussed.

TL;DR: In this article, a review of studies of the transmission of translational seat vibration to the heads of seated subjects is presented to determine the variations in transmissibility of these transmissions.