Development of a Precipitation Gauge Using Ultrasonic Measuring Technique

The thermal pulse decay technique for measuring ultrasonic absorption coefficients

The classic method for measuring absorption coefficients ofmaterials requires adetermination of the temperature rise within a medium during ultrasonic irradiation. Serious errors may result from a viscous heating effect around the required thermocouple probe, and from heat lost by conduction to surrounding, cooler egions. A thermal pulse-decay technique is proposed and evaluated which allows fo...

Infrared Technique for Measuring Ultrasonic Absorption in Polycrystalline Metals

the effect of using visual aids on the development of speech act of disagreement among iranian intermediate efl learners

abstract the present study tried to investigate the effect of visual aids (films) on the development of the speech act of disagreement among iranian efl intermediate learners. to this end, the researcher selected 40 homogeneous intermediate learners based on their scores on oxford placement test. .the subjects then divided into control group and experimental group. both classes were tested by ...

Direct measurement of ultrasonic dispersion using a broadband transmission technique

A broadband, through-transmission technique is described that measures directly the change in phase velocity with frequency without first measuring the absolute phase velocity at different frequencies. The method only requires the measurement of the specimen’s thickness and recording of two pulses: one without and one with the specimen inserted between the transmitting and receiving transducers...

Ultrasonic Attenuation Measurement Using Backsgattering Technique

Ultrasonic backscattering measurements by means of spatial averaging technique were carried out in steel to determine the ultrasonic attenuation coefficient. The attenuation coefficients were evaluated from the exponential decay of the backscattering signal. The results were compared with those obtained by evaluating the amplitude decay of the main pulse. Good agreement is observed provided the...