In underwater environment the acoustical wave can transmit a long ranges away from the transmitter than the electromagnetic wave does. So far, the piezoelectric ceramic is still the best candidate as acoustical telemetry transmitters in underwater applications. The impedance matching on the interface between electro-acoustical transducer and electrical transmitter has been the most important su...

The alternating current resistance and capacity of suspensions of unfertilized and fertilized eggs of Arbacia punctulata have been measured at frequencies from 10(3) to 1.64 x 10(7) cycles per second. The unfertilized egg has a static plasma membrane capacity of 0.73 microf./cm.(2) which is practically independent of frequency. The fertilized egg has a static membrane capacity of 3.1 microf./cm...

Alternating current resistance and capacity measurements have been made from 1.08 10(3) to 2.32 10(6) cycles per second on suspensions of unfertilized, fertilized, and swollen unfertilized eggs of the echinoderm Hipponoë esculenta. A simple method has been developed for measuring the volume concentration of eggs in a suspension. The membrane of the unfertilized egg is practically non-conducting...

As the number of publicly-available datasets are likely to grow, the demand of establishing the links between these datasets is also getting higher and higher. For creating such links we need to match their schemas. Moreover, for using these datasets in meaningful ways, one often needs to match not only two, but several schemas. This matching process establishes a (potentially large) set of att...

This paper presents kinematic and dynamic analysis of a holonomic vehicle with continuously-variable transmission. Four ball wheels, independently actuated by DC motors, enable for moving the vehicle in any direction within the plane and rotating it around its center. The angle between the two beams holding the balls can be changed to alter the gear ratio and other dynamic characteristics of th...

We proposed a new expression of speech feature called orientation patterns which keeps its ability of detection higher in averaging of time domain. Because of this, we achieved to reduce number of frames in reference and input pattern in DP matching algorithm, then the calculation load were reduced. We constructed long term speech retrieval system by using this new expression. This system has R...

Electromagnetics has an important role in power and energy industry. In this paper, the concept of rectenna is introduced firstly. The history of rectenna for wireless energy harvesting and transmission is then reviewed. Finally examples are employed to illustrate some rectenna design and measurement issues such as rectenna impedance matching and its conversion efficiency. It is also shown that...

Today’s modern commercial and military communication systems are demanding better performance with regards to power, effi ciency, linearity and operating bandwidth. As such, extra considerations must be placed on designing the internal components of the systems, including the low-noise and power amplifi ers, to maximize performance. In order to reach higher effi ciencies, signifi cant research ...

Klectrie impedance plethysmography has been offered as a substitute for mechanical plethysmography and would be particularly suitable for regions in which the mechanical method cannot be applied. A comparative investigation of mechanical and impedance plethysmograms, taken simultaneously from a finger or a forearm, revealed that, while the normal pulsations were reproduced reasonably well, elec...