investigations on vibration behaviors of railway track systems were attempted in this research. this was made by conducting a comprehensive field investigation into the free vibration of track systems and response of tracks to train moving loads. in-situ modal analysis was used in a railway track field as an efficient method of investigating dynamic properties of railway track systems. natural ...

The vibration of an elastic beam experiencing vortex-induced vibration is numerically analyzed through a wake-oscillator model using the finite differences method. The influence of the excited mode, the initial velocity, the shedding pulsation and the mass ratio on the energy transfer among modes and the vibration amplitude is determined. Multiple frequencies are detected, and the power spectra...

One of the major problems in experimental vibration analysis is to determine location of transducers. It is important to place the transducers on locations with largest vibration amplitude and to avoid locations with zero-movement (nodal lines). These locations are best seen from vibration mode shapes. Finite element analysis (FEA) provides numerical values for natural frequencies, which are so...

Introduction: Due to the non-developed mechanization situation, chainsaw is a widely used tool in Iranian forests. This tool can trigger unwelcome disorders (e.g., white finger syndrome) due to the transmitted vibrations from its handle to the body members. Characterizing these vibrations can result in minimizing the intensity of these disorders. This study aims to investigate the effect of dif...

different methods for detecting broken bars in induction motors can be found in literature. many of these methods are based on evaluating special frequency magnitudes in machine signals spectrums. current, power, flux, etc are among these signals. frequencies related to broken rotor fault depend on slip. in industrial environment due to some phenomena - such as load oscillation, other faults an...

An analysis has been presented of the effect of elastic foundation and uniform in-plane peripheral loading on the natural frequencies and mode shapes of circular plates of varying thickness exhibiting bi-directional functionally graded characteristics, on the basis of first order shear deformation theory. The material properties of the plate are varying following a power-law in both the radial ...

In this work,The free nonlinear vibrations of nanotubes using the Euler-Bernoulli beam theory along with the von Kármán geometric nonlinearity in presence of surface effects has been investigated. Natural frequencies of a simply-supported nanotube in terms of the Jacobi elliptic functions are obtained by using the free vibration modes of the corresponding linear problem. The numerical results d...

Key elastic properties of full-sized wood composite panels (WCPs) must be accurately determined not only for safety, but also serviceability demands. In this study, the modal parameters of full-sized WCPs supported on four nodes were analyzed for determining the modulus of elasticity (E) in both major and minor axes, as well as the in-plane shear modulus of panels by using a vibration testing m...

Fabrication, characterization and application of micro-/nano-rods/wires are among the hottest topics in materials science and applied physics. Micro-/nano-rod-based structures and devices are developed for a wide-ranging use in various fields of micro-/nanoscience (e.g. biology, electronics, medicine, optics, optoelectronics, photonics and sensors). It is well known that the structure and prope...