The oil and gas industry has a growing demand for electrically driven trains operated at variable speeds. Variable frequency electrical drives enable increased operational flexibility and energy efficiency. This is of great importance in applications requiring high power, such as gas compression. Load commutated inverters (LCIs) are one of the most widespread technologies for driving large gas ...

Structural instability caused by self exciting aerodynamic forces (flutter) can be used as an effective input source for small scale energy harvesters. The self exciting aerodynamic force exerted on a T-shape cantilever causes periodic vibration, which can be converted into electric power through an electromagnetic transducer. Due to the complexities inherent in the fluid-structure interaction ...

Structural instability caused by self exciting aerodynamic forces (flutter) can be used as an effective input source for small scale energy harvesters. The self exciting aerodynamic force exerted on a T-shape cantilever causes periodic vibration, which can be converted into electric power through an electromagnetic transducer. Due to the complexities inherent in the fluid-structure interaction ...

The nonlinear vibration analysis of a directly excited cantilever beam modeled as an inextensible viscoelastic Euler–Bernoulli beam has been studied by the authors and is reported in the literature. The viscoelastic damping was modeled as Kelvin–Voigt damping, and the nonlinearities arisen from the inextensibility assumption. This paper extends our theoretical developments presented in the prev...

Semi-active control systems are becoming more popular because they offer both the reliability of passive systems and the versatility of active control systems without imposing heavy power demands. In particular, it has been found that magnetorheological (MR) fluids can be designed to be very effective vibration control actuators, which use MR fluids to produce controllable damping force. The ob...

The seismoscope is a simple instrument designed originally to give a largely qualitative indication of the strong ground motions produced by an earthquake. It consists of a smoked watch glass attached to a two-degree-of-freedom pendulum with a period of 1⁄4 sec and damping about 10 per cent of critical; a pen records the pendulum motions on the watch glass. One point on the displacement spectru...

The structural health monitoring system (SHMS) provides an effective tool to conduct full-scale measurements on existing bridges for essential research on bridge wind engineering. In July 2008, Typhoon Fung-Wong lashed China and hit Sutong cable-stayed bridge (SCB) in China. During typhoon period, full-scale measurements were conducted to record the wind data and the structural vibration respon...

ABSTRACT. S-transformation is proposed to evaluate the quality of completed turning operations. The calculated time-frequency-amplitude plot of an accelerometer or cutting force signal indicates the vibration level at different frequencies and helps the operator to identify the problems. Time-frequency-damping index plots were obtained by using the s-transformation. Variance of damping index in...