In demand for low-loss wide-band communication devices, Potassium niobate (KNbO3) is now receiving renewed interests because it has been found to exhibit high electromechanical coupling. This paper describes the optimum cuts of KNbO3 for bulk acoustic waves (BAW) and surface acoustic waves (SAW) devices, with expectation of their application in the future. In addition, our recent works on growt...

The idea of a piezoelectric transformer (PT) was first implemented by Rosen (Rosen, 1956), as shown in Fig.1. It used the coupling effect between electrical and mechanical energy of piezoelectric materials. A sinusoidal signal is used to excite mechanical vibrations by the inverse piezoelectric effect via the driver section. An output voltage can be induced in the generator part due to the dire...

OBJECTIVE In Turkey, a type of smokeless tobacco called Maras powder (MP) is widely used in the south-eastern region. Smokeless tobacco is found in preparations for chewing and for absorption by the nasal and oral mucosae. The purpose of this study was to investigate whether MP damages intra- and inter-atrial conduction delay and left atrial (LA) mechanical function as much as cigarette smoking...

High energy electron (1.0±2.55 MeV) irradiation was used to modify the phase transitional behavior of poly(vinylidene ̄uoridetri ̄uoroethylene) (P(VDF-TrFE)) copolymers in an attempt to signi®cantly improve the electromechanical properties of the copolymers. It is found that the copolymers under a proper irradiation treatment exhibit very little room temperature polarization hysteresis and very ...

Very small electromechanical coupling coefficient in micro-electromechanical systems (MEMS) or acoustic resonators is quite a concern for oscillator performance, specially at mmWave frequencies. This the manifestation of ratio motional capacitance to static resonators. work provides general solution overcome problem relatively high frequencies and presents analysis design techniques achieving e...

It is known that the heart interacts with and adapts to its venous and arterial loading conditions. Various experimental studies and modeling approaches have been developed to investigate the underlying mechanisms. This paper presents a model of the left ventricle derived based on nonlinear stress-length myocardial characteristics integrated over truncated ellipsoidal geometry, and second-order...

In this paper, phase and speed synchronization control of four eccentric rotors (ERs) driven by induction motors in a linear vibratory feeder with unknown time-varying load torques is studied. Firstly, the electromechanical coupling model of the linear vibratory feeder is established by associating induction motor's model with the dynamic model of the system, which is a typical under actuated m...

In this paper we use a simplified model of cardiac excitation-contraction coupling to study the effect of tissue deformation on the dynamics of alternans, i.e., alternations in the duration of the cardiac action potential, that occur at fast pacing rates and are known to be proarrhythmic. We show that small stretch-activated currents can produce large effects and cause a transition from in-phas...