Air-coupled ultrasonic inspection using leaky Lamb waves offers attractive possibilities for non-contact testing of plate materials and structures. A common method uses an air-coupled pitch-catch configuration, which comprises a transmitter and a receiver positioned at oblique angles to a thin plate. It is well known that the angle of incidence of the ultrasonic bulk wave in the air can be used...

although in recent two decades, the concept of dielectric barrier discharges (dbds) have been developed in ozone production well, air pollution control, plasma screens and control of chemical, and biological and medical processes, employment of this concept for high voltage applications to improve insulation performance as an alternative to the pressurized gas-insulated systems (gis) utilizing ...

This paper utilizes the wavelet packet transform to study the effects of decreasing the number of slots per pole per phase on the harmonic behavior of the working flux density in the air gap. A surface mounted PM motor is used as an example. The original design contains 6 PM poles and 36 stator slots with three phase winding embedded. The rotor is redesigned to have 4, 8, and 12 poles mounted o...

OBJECTIVE To determine whether middle ear cholesteatoma is associated with, sensorineural hearing loss, and whether patient age, cholesteatoma growth pattern, or, air bone gap size contribute to inner ear impairment. STUDY DESIGN Cross-sectional comparative. SETTING A tertiary hospital. PATIENTS The subjects were 115 patients with middle ear cholesteatoma in one ear, and normal video-otos...

A 37-year-old female was admittedwith bilateral hearing loss since her childhood. On examination of the case with no other complaint, the EACs were short and closed conically. There was a conductive type of hearing loss at 50 dB in the right ear (air bone gap 40 dB) , and at 47 dB (air bone gap 37dB) in the left ear on the pure tone audiogram. On temporal bone CT, bilateral the EACs were observ...

The dispersed particles of magnetorheological fluid form stable chain-like clusters under the magnetic field, and show an effect of controllable flowability and shape. Based on this characteristic, using migration magnetic acted on the magnetorheological fluid, the object directional migration can be realized, and then the magnetorheological fluid forms levitation at the same time, which has li...

An important step in the verification of the reliability of portal films as in vivo dosemeters is the evaluation of the agreement between exit dose profiles and optical density profiles measured on the portal film. To test the possibilities of a conventional portal film system in 60Co beams suitable for head and neck irradiation, we verified the agreement between relative exit doses (measured b...

An optical instrument for measuring the thickness of a thin gap or transparent lm is presented. It will be used to calibrate the adaptive secondary mirror under development for the Steward Observatory 6.5 m Multiple Mirror Telescope. Capacitive sensors in the mirror assembly measure dynamically the thickness of the nominally 50 m air gap between the deformable mirror and a glass reference body....

Waveguiding phenomena are investigated in an inverted opal photonic crystal made of interpenetrating air spheres, coated with amorphous Ge. Here we focus on the complete gap between the 8th and the 9th band, since a projected band analysis reveals that it is difficult to use the large lower incomplete gap for guiding purposes. Two kinds of line defects are analyzed within this photonic structur...

Abstract: In this research, we attempt to envisage the mirror application using semiconductor photonic crystal with the help of photonic bandgap analysis. The photonic bandgap of photonic crystal structure is simulated using plane wave expansion method, where photonic crystal is realized by 2D triangular photonic crystal structure with gallium arsenide as background material having periodic air...