Piezoelectric stack actuators (PESAs) are widely used in applications requiring a fast response, high resolution, and accuracy. The self-heating of PESA during continuous drive with large amplitude at frequencies can change its voltage displacement charge characteristics. These changes lead to loss stability inaccurate positioning systems. In this paper, we confirmed that by using our proposed ...

i ABSTRACT Nowadays transducers are ubiquitous as interfaces between the increasingly digital world and the real physical world. The same holds for the power amplifiers driving them. This thesis focuses on the design and optimization of high-voltage class-D amplifiers, which are used for driving capacitive piezoelectric actuator loads in active vibration/noise control applications. The main obj...

rock chutes are natural river training structures and are efficient energy dissipaters too. from the hydraulic and environmental point of view, rock chutes have become important structures in the natural river morphology. a physical study was conducted and flow properties were measured over rough bed materials of a rock chute, which was assembled at the pitlab center of the university of pisa, ...

A flexible gusset is a device that improves the seismic resistance and energy dissipation capacity of structure. To achieve these solo vibration characteristics, designed to remain elastic, resulting in reduced The energy-absorbing attached column with bolts, thereby connecting ties putting them into operation while dissipating vibration. proposed design was theoretically studied using modeling...

In this paper, a new indicator to localize fatigue damage in fibre glass composite structure, i.e. spar cap shear web thick adhesive joint of wind turbine blade, is presented. This based on the effect damping phase mode shapes structure. When occurs, increases defective area and leads an increase local energy dissipation. non-uniformity dissipation throughout structure causes vibrate with whose...

The Millikan Library Building, a nine-story reinforced concrete shear-wall structure at the California Institute of Technology, was tested dynamically by means of two eccentric mass vibration generators located on the ninth floor. The response levels ranged up to a maximum acceleration of 0:02 g. The natural periods of vibration, the mode shapes and the energy dissipation were measured for the ...

A continuous compaction control energy model suitable for contact decoupling between the vibrating wheel and filling body surface is established through analyzing state of in detection stage calculating nonlinear vibration dissipation rate based on basic principle technology conservation. The significance parameters contained analyzed, index-dissipation measured value (DMV) evaluating quality p...

Air bubbles mixed in the hydraulic oil of power transmission systems causes deterioration dynamic characteristics system, component erosion, accelerated oil, reduced heat dissipation, and vibration noise. In this paper, a method to controlling air bubble content by swirling flow working has been proposed developed. The amount flowing out separation device can be adjusted opening closing valve o...

This study focusses on the vibration transmission and energy flow characteristics of low dimensional models dynamical systems with Coulomb friction. The Karnopp friction model smooth are employed to estimate dry force. steady-state responses system determined by harmonic balance (HB) approximations numerical continuations a time-marching method. level dissipation within assessed force transmiss...

recently the stepped spillways have been used as an appropriate solution for energy dissipation. in the present study, siahbisheh dam spillway is simulated by using computational fluid dynamic (cfd), in which the mixture method and reynolds stresses model (rsm) turbulence model is used. in the first modeling series the over all steppes slope is constant. the number of the steps is increased to ...