This article deals with effects of thermal stresses on stability and frequency response of a fully clamped circular microplate, which acts as the diaphragm of a capacitive MEMS microphone. Static and dynamic pull-in phenomena limit the stable regions of a capacitive MEMS microphone. The results show that the non-dimensional static pull-in voltage of the studied case is about 5.23 (38.6 V). On t...

This paper aims to investigate the pull-in phenomenon of functionally graded (FG) capacitive nanocantilevers subjected to an electrostatic force and thermal moment due to an applied voltage and thermal shock considering intermolecular force within the framework of nonlocal elasticity theory to account for the small scale effect. The FG nano-beam is made of mixture of metal and ceramic which the...

This paper deals with the effect of the intrinsic material length-scale parameter on the stability and natural frequency of a rectangular micro-plate for two different cases; fully clamped and fully simply supported. A variational formulation based on Hamilton’s principle and the modified couple stress theory is used to obtain the nonlinear governing equation of a micro-plate incorporating the ...

Jump and pull-in instability are common nonlinear dynamic behaviors leading to the loss of performance reliability structural safety electrostatic micro gyroscopes. To achieve a better understanding these initial-sensitive phenomena, dynamics gyroscope system considering nonlinearities stiffness forces explored from global perspective. Static analyses performed estimate threshold detecting volt...

In this research, a functionally graded microbeam bonded with piezoelectric layers is analyzed under electric force. Static and dynamic instability due to the electric actuation is studied because of its importance in micro electro mechanical systems, especially in micro switches. In order to prevent pull-in instability, two piezoelectric layers are used as sensor and actuator. A current amplif...

in this paper, the stability of a functionally graded magneto-electro-elastic (fg-mee) micro-beam under actuation of electrostatic pressure is studied. for this purpose euler-bernoulli beam theory and constitutive relations for magneto-electro-elastic (mee) materials have been used. we have supposed that material properties vary exponentially along the thickness direction of the micro-beam. gov...

[Purpose] Our objective was to evaluate the residual dynamic and static functionality in the sitting position of hemiplegic stroke patients who require help to pull their lower garments up and down during toileting. [Subjects and Methods] The subjects were 11 hemiplegic patients. We gathered data on the patients' motor paralysis, sensory capacity, lower extremity muscle strength, trunk control,...

This work studied the static magnetic pull of a modular spoke-type permanent magnet motor (MSTPMM) with no rotor eccentricity during motor’s final assembly process and its dynamic different operating states. A new scheme was proposed to significantly reduce motor. The methods required unbalanced radial whole stator, which is caused by partial stator module operation, were also studied. Firstly,...

The release of nonaqueous phase liquids (NAPLs) to the subsurface environment can create long-term sources of ground water contamination as the NAPL slowly dissolves into ground water (Mercer and Cohen 1990; Cohen and Mercer 1993). Effective remediation of subsurface NAPL contamination requires that NAPL be accurately located and saturations quantified. This is particularly important for dense ...