Piezoelectric Transducer and its Applications (III)

Horn-Type Piezoelectric Ultrasonic Transducer: Modelling and Applications

1-3 Piezoelectric Composites for High Power Ultrasonic Transducer Applications

In this paper, we demonstrated that 1-3 PZT/polymer composites, fabricated using PZT-4 ceramic and a polymer possessing a high glass transition temperature and low loss, can be used as high power ultrasonic transducer materials for high intensity focused ultrasound (HIFU) applications. The mechanical quality factor of the 1-3 composite with 64% ceramic volume fraction is over 200. The dielectri...

Aluminum Nitride Piezoelectric Micromachined Ultrasound Transducer Arrays

Air-coupled piezoelectric micromachined ultrasound transducer arrays, operating at ~190 kHz, have been fabricated utilizing an aluminum nitride piezoelectric layer. Improved fabrication processes have reduced the frequency variation seen in our previous work with single transducers resulting in arrays of transducers with resonant frequencies (fn) that match within the fractional half-power band...

A Low-Power CMOS Piezoelectric Transducer Based Energy Harvesting Circuit for Wearable Sensors for Medical Applications

Piezoelectric vibration based energy harvesting systems have been widely utilized and researched as powering modules for various types of sensor systems due to their ease of integration and relatively high energy density compared to RF, thermal, and electrostatic based energy harvesting systems. In this paper, a low-power CMOS full-bridge rectifier is presented as a potential solution for an ef...

Benford Distribution and its Applications

‎This papers considers the Benford distribution as one the interesting rules of probability theory‎. ‎This rule shows that‎, ‎despite of usual underestanding about the uniform distribution of digites‎ ‎for lieing on different positions in numbers‎, ‎digits are distributed according to an non uniform distributions for numbers araising from many natural phonemena‎. ‎Benford distribution proposes ...