in the current study the effect of casimir force and squeezed film damping on the pull-in instability and dynamic behavior of electrostatically actuated nano and micro electromechanical systems is investigated separately. linear elastic membrane theory is used to model the static and dynamic behavior of system for strip, annular and disk geometries. squeezed film damping effect is modeled using...

In the current study, the effects of Casimir force and squeeze film damping on pull-in instability and dynamic behavior of electrostatically actuated nano and micro electromechanical systems are investigated separately. Linear elastic membrane theory is used to model the static and dynamic behavior of the system for strip, annular and disk geometries. Squeeze film damping is modeled using nonli...

Considering the strategic importance of coastal areas from various aspects, their protection against waves is a coast management necessity. Since long ago, strong coastal structures have protected coasts, but since they disturb the coastal ecosystem balance, effort has been made to use them less or make them more compatible with the coast. This research is specifically aimed to estimate the eff...

This paper is concerned with efficient integration of bilinear H∞ control and adaptive inverse control to attain vibration isolation of structure installed with a semi-active MR damper in which its damping force is controllable by input voltage. The structure with MR damper is expressed by a bilinear dynamic equation. The role of the bilinear H∞ controller is to provide the desired damping forc...

The present study focusses on the damping force control of shear mode magnetorheological (MR) damper for seismic mitigations. Therefore, the semi-active MR damper which can control the vibration is analyzed both experimentally and numerically. Carbonyl iron is used as the magnetic particle and Castrol Magnetec oil as carrier fluid throughout the study. MR damper is designed and fabricated, and ...

It is shown that among the various damping mechanisms that are generally encountered in a mechanical structure, only the “viscous component” actually accounts for energy loss. The remaining portion of the damping force is due to non-linearities, which do not dissipate energy. Consequently, a linear model of a vibratory mechanical system involves only viscous damping, although the damping factor...

This paper discusses the damping measurements on cables with real-time controlled MR dampers that were performed on a laboratory scale single strand cable and on cables of the Sutong Bridge, China. The control approach aims at producing amplitude and frequency independent cable damping which is confirmed by the tests. The experimentally obtained cable damping in comparison to the theoretical va...

The theory of damping is discussed in Newton's Principia and has been tested in objects as diverse as the Foucault pendulum, the mirrors in gravitational-wave detectors and submicrometre mechanical resonators. In general, the damping observed in these systems can be described by a linear damping force. Advances in nanofabrication mean that it is now possible to explore damping in systems with o...

Pre-stress techniques tend to increase cross-sectional capacity and optimize design. Such features have made these techniques rather popular. Over time, these structures tend to fail, and the reduction of pre-stress force over the lifetime of the structure is said to be one of the most significant destructive factors in these structures. This decrease in force occurs due to various reasons. In ...