The dynamic response of an oscillating microcantilever with a gold-coated tip interacting with dissimilar functionalized silica surfaces was studied in electrolyte solutions with pH ranging from 4 to 9. Silica surfaces were chemically modified, yielding dissimilar surfaces with -Br, -NH(2), and -CH(3) functional group terminations. The relative hydrophobicity of the surfaces was characterized b...

Nowadays it is commonly considered that high damping materials which have both the good mechanical properties as structural materials and the high damping capacity for vibration damping are the most direct vibration damping solution. In metals and alloys however, exhibiting simultaneously high damping capacity and good mechanical properties has been noted to be normally incompatible because the...

In this study, the damping mechanism at the interface of the mating spur gear teeth is investigated. The dynamic behaviour of a spur gear pair is represented by a two Degree-of-Freedom (DOF) nonlinear model with the damping provided by the instantaneous tribological behaviour of the tooth contacts. The shear stress distributions along the tooth surfaces are incorporated with the dynamic model t...

this work is conducted to obtain mechanical properties of microtubule. for this aim, interaction energy in alpha-beta, beta-alpha, alpha-alpha, and beta-beta dimers was calculated using the molecular dynamic simulation. force-distance diagrams for these dimers were obtained using the relation between potential energy and force. afterwards, instead of each tubulin, one sphere with 55 kda weight ...

The effect of nanoclay on various material properties like damping and strength of typical thermoset polymers, such as epoxy and vinyl ester, was investigated. Different environmental conditions typical for high-voltage transmission pylons made of composite materials were taken into account. Resin samples were prepared with various clay weight fractions ranging from 0% to 3%. Scanning electron ...

Hunting is a flutter associated with the synchronous speed that gives rise to the gyro drifting errors and may cause objectionable time-displacement errors in video head wheel drives and other precision scanning systems. In this paper, dynamic characteristics of permanent Magnet hysteresis motors are presented and hunting is explained. New damping techniques have been developed using optimi...

The uncertainty associated with damping in structural systems is identified and discussed. A second-order perturbation technique is utilized to examine the effects of damping variability on the transient and steady-state dynamic response of structural systems. The results demonstrate that the uncertainty in damping indeed influences the system response. The effects are more pronounced for highe...

This paper presents a finite element formulation for the dynamics analysis of the steady and transient states of a nonlinear piezoelectric beam. A piezoelectric beam with damping is studied under harmonic excitation. A numerical method is used for this analysis. In the paper, the central difference formula of four order is used and compared with the central difference formula of two order in th...

FACTS devices can help the damping of power system oscillations. The objective of this paper is to design and propose a systematic approach for damping controller to validate results by comparing with lab prototype. This paper presents a control scheme, comprehensive analysis and result obtained for the dynamic control of power transmission, damping of oscillations with Unified Power Flow Contr...