The sonoelastographic theory of tumor detection predicts enhanced image contrast as vibration frequency increases. However, the opposite effect is observed when imaging liver lesions at frequencies (200-400 Hz) where strong viscoelastic effects dominate. Mechanical testing was performed and confirmed the viscoelasticity of liver tissue. The time dependence of the stress relaxation suggests a vi...

Active vibration control is an important problem in structures. The objective of active vibration control is to reduce the vibrations of a system by automatic modification of the system’s structural response. In this paper, the modeling and design of a fast output sampling feedback controller for a smart flexible beam system embedded with shear sensors and actuators for SISO system using Timosh...

A method based on the power series solution is proposed to solve the natural frequency of flapping vibration for the rotating inclined Euler beam with constant angular velocity. The vibration of the rotating beam is measured from the position of the corresponding steady state axial deformation. In this paper the governing equations for linear vibration of a rotating Euler beam are derived by th...

An analytical solution for nonlinear vibration of an initially stressed beam with elastic end restraints resting on a nonlinear elastic foundation is obtained. As a first step in solving nonlinear vibration equation, the linear vibration mode functions for a beam with elastic end restraints resting on a linear elastic foundation are obtained. Then, the nonlinear vibration equation is solved by ...

We report on the use of a high-speed wavelength division multiplexing (WDM) technique for multiplexing Fiber Bragg Grating (FBG) sensors applied to structural Vibration Control for the measurement of strain, permitting many sensing devices along a single optical fiber at different locations collecting samples at 5000 Hz with microstrain resolution. In this demonstration, a cantilevered flexible...

The boring operation is a very critical manufacturing process which created surface roughness, tool wear, noise and vibration related problems. A deep internal boring operation in a workpiece is a classic example of chatter-prone machining. This review focuses on study of new damping composite materials for boring tool and introduces new advance viscoelastic materials for vibration attenuation ...

The aim of this paper is firstly to address the consequences of the nonlinear interactions between higher order modes and the first order mode of a flexible cantilever beam. The tested cantilever beam exhibited numerous nonlinear phenomena that are commonly observed in many flexible structures. The experimental results have shown that active control of the nonlinear vibration in a flexible stru...

The vibration problems of uniform and nonuniform Euler-Bernoulli beams have been solved analytically or approximately [1-5] for various end conditions. In order to calculate fundamental natural frequencies and related mode shapes, well known variational techniques such as Rayleigh_Ritz and Galerkin methods have been applied in the past. Besides these techniques, some discretized numerical metho...

In this paper the vibration and the traveling wave in a coupled magneto-elastic beam system are discussed experimentally. The vibration excited by the periodical forcing at the beam system propagates to another as a wave through the coupling elastic beams. Each magneto-elastic beam shows the variety of vibrations caused by the nonlinearity of the potential well and the wave propagation with tim...

INTRODUCTION The lower ratio of dead load to live load than existing multi-girder bridges, wide girder spacing and simplified structural system of the twin-girder bridges can give rise to change of dynamic characteristics of the bridges. Wider girder spacing and changing of dynamic features will also effect on a vibration serviceability of the bridges. What is worse, according to running vehicl...