A MEMS vibration-driven electret generator for energy harvesting has been developed. Parylene high-aspect-ratio flexible spring is employed to support the seismic mass with high-performance patterned electret. The seismic structure enables large in-plane oscillation amplitude of 1 mm and low resonant frequency of 37Hz. With our early prototype, we have obtained 21 Vp-p voltage output, correspon...

In the forward flight, wind loads affect helicopters and cause vibration. This paper analyzes behavior of a helicopter prototype composed by two blades when subjected to front load, similar forwarding flight condition. An Artificial Neural Network (ANN) processes experimental data in order identify pattern its dynamic behavior. The tests led Vibration analysis for different speeds. Also, indica...

this paper is concerned with the surface and small scale effects on transverse vibration of a viscoelastic single-layered graphene sheet (slgs) subjected to an in-plane magnetic field. the slgs is surrounded by an elastic medium which is simulated as visco-pasternak foundation. in order to investigate the small scale effects, the nonlocal elasticity theory is employed due to its simplicity and ...

This paper investigates the parametric stability of an axially moving web subjected to non-uniform in-plane edge excitations on two opposite, simply-supported edges. The web is modeled as a viscoelastic plate whose constitutive relation obeys the Kelvin-Voigt model, and the in-plane edge excitations are expressed as the sum of a static tension and a periodical perturbation. Due to the in-plane ...

Introduction: Diffusion tensor imaging (DTI) offers the possibility of estimating quantities that are related to the brain’s white matter (WM) microstructure, e.g. the fractional anisotropy (FA) [1].These quantities are frequently used for group comparisons (e.g. [2]). For DTI, at least seven images must be acquired [3]: one image with no diffusion sensitization (b0 image), and six diffusion-we...

Abstract—The effect of non-homogeneity on the free transverse vibration of thin rectangular plates of bilinearly varying thickness has been analyzed using generalized differential quadrature (GDQ) method. The non-homogeneity of the plate material is assumed to arise due to linear variations in Young’s modulus and density of the plate material with the in-plane coordinates x and y . Numerical re...

The averaged dynamics of various two-phase systems in a high-frequency vibration field is studied theoretically. The continuum approach is applied to describe such systems as solid particle suspensions, emulsions, bubbly fluids, when the volume concentration of the disperse phase is small and gravity is insignificant. The dynamics of the disperse system is considered by means of the method of a...

Periodic composite ultrasonic transducers offer many advantages but the periodic pillar architecture can give rise to unwanted modes of vibration which interfere with the piston like motion of the fundamental thickness mode. In this paper, viscoelastic loss is incorporated into a three-dimensional plane wave expansion model (PWE) of these transducers. A comparison with experimental and finite e...

This paper deals with the finite element approximation of the vibration modes of a laminated plate modeled by the Reissner-Mindlin equations; DL3 elements are used for the bending terms and standard piecewise linear continuous elements for the in-plane displacements. An a priori estimate of the regularity of the solution, independent of the plate thickness, is proved for the corresponding load ...