As a fundamental study on the electric method for measuring root canal length, the various factors which affect the measured impedance were investigated using a wide range of frequencies. 1) The impedance between two saliva ejectors in contact with the oral mucosa near the bilateral premolars in the lower arch generally showed low values. The difference between the maximum and minimum measured ...

Any AM antenna system consists of the antenna itself, some sort of transmission line to convey the RF energy from the transmitter to the antenna, and some sort of impedance matching network. Directional antenna systems consist of multiple radiating elements, transmission lines and matching networks. In this paper, we will examine in building-block fashion the components that make up such system...

Complex impedance and conductivity were measured for regioregular poly(3hexylthiophene) (P3HT) at alternating current (AC) voltages using a waveform technique. The waveforms were Fourier transformed from time domain to frequency domain and analyzed at fundamental and higher order harmonic frequencies. It was found that the impedance of the semi-conducting P3HT decreases with increasing electric...

A new method that is based on genetic algorithm (GA) is developed to design electrical impedance matching network for broadband piezoelectric ultrasound transducer. The new method can both optimize the topology of the matching network and perform optimization on the components at the same time. Results of classical algorithms are referenced to reduce the number of candidate topologies and great...

This paper addresses the performance evaluation of a modified square loop antenna design for UHF RFID applications that is excited through a narrow feed line connected to a square loop, an impedance matching network. The square loop dimensions are modified to reach a conjugate impedance matching. A gap is fixed between the feed-lines to link the chip. To achieve impedance matching, the structur...

This paper presents the simulation and optimization design of the electronically tunable impedance-matching networks for intelligent RF power amplifiers in a cognitive radio system. Reconfigurable elements, such as varactors and RF switches are utilized to achieve the dynamic impedance matching both in the input and output matching circuit, providing coarse and fine tuning of the target impedan...