in this paper a new form of the homptopy perturbation method is used for solving oscillator differential equation, which yields the maclaurin series of the exact solution. nonlinear vibration problems and differential equation oscillations have crucial importance in all areas of science and engineering. these equations equip a significant mathematical model for dynamical systems. the accuracy o...

Whole body vibration (WBV) has been suggested as an alternative form of exercise producing adaptive responses similar to that of resistance training. Very limited information is available on the effects of different vibration parameters on anabolic hormones. In this study, we compared the acute effects of different WBV amplitudes on serum testosterone (T) and insulin growth factor-1 (IGF-1). Ni...

A pilot study investigating the influence of vibration during press ups on myoelectrical activity of both dynamic and stabiliser muscles. Nine male participants (21.1 ± 3.4 years, 1.68 ± 0.03 m, 72.3 ± 9.5 kg), performed press ups under 3 conditions: without vibration, low amplitude and frequency vibration (30L; 1.2 mm, 30 Hz) high amplitude and frequency vibration (40H; 1.9 mm, 40 Hz). Press u...

An explicit solution for the vibration of a carbon chain inside carbon nanotubes (CNTs) was obtained using continuum modeling of the van der Waals (vdW) interactions between them. The effect of the initial tensile force and the amplitude of the carbon chain as well as the radii of the CNTs on the vibration frequency were analyzed in detail, respectively. Our analytical results show that the vib...

This paper presents the design and characterization of micro-fabricated 0.5 MHz silicon-based ultrasonic nozzles. Each nozzle is made of a piezoelectric drive section and a silicon-resonator consisting of five Fourier horns, each with half wavelength design and twice amplitude magnification. Results of impedance analysis and measurement of longitudinal vibration confirmed the simulation results...

Equal channel angular pressing (ECAP) is one of the most prominent procedures for achieving ultra-fine grain (UFG) structures among the various severe plastic deformation (SPD) techniques. In this study, the effect of ultrasonic vibration on deformation behavior of commercial pure aluminum in the ECAP process is analyzed successfully using three dimensional (3D) by finite element methods (FEMs)...

The aim of this work is the application of the phase variation in vibration signal for fault detection on rotating machines. The vibration signal from the machine is modulated in amplitude and phase around a carrier frequency. The modulating signal in phase is determined after the Hilbert transform and is used, with the Fast Fourier Transform, to extract the harmonics spectrum in phase. This me...

Nanoimprinting is a simple and efficient way to generate nanopatterns over a large area by pressing a master mould to penetrate into the surface of a substrate. It is known that interfacial friction force is a main factor responsible for pattern defects in nanoimprints. Here, nanoimprinting of metals by carbon nanotube arrays under a high-frequency vibration perturbation were studied via molecu...

Many people experience vibration effects on whole-body throughout their lives frequently. Vibrating energy absorbed is exposed all-body caused with vibration hazard in the vertically on body and biodynamic responses from body in speed 2.37 to 5.14 m/s could captivate with car seat on user body, so the vibration energy transferred to a seated people body. In this paper, the human body is modeled...