The well-known thermo-elastic effect of laser irradiation can be exploited to produce strong localized stresses when an expanded, long pulse, low-intensity laser beam is used to irradiate the specimen. These stresses will produce a parametric modulation of the received ultrasonic signals, that is somewhat similar to the acousto-elastic effect often used in nonlinear ultrasonic studies. It is sh...

The effects of applied tensile stresses on the temperature dependence of 10 MHz ultrasonic longitudinal velocity have been studied in three types of commercial aluminum alloys, 6064-T4, 2024-T351, and 3003-T251. In all measurements, it is found that the velocity decreases linearly with temperature, and the slope of the linear relationshi'p changes considerably as a function of applied tensile s...

In fluctuating airflow, continuous air velocity recording is the most reliable method of air velocity measurement. It allows for fast recognition of changes and the calculation of long-term averages. Also, it enables the mine operator to identify when the airflow has decreased to a point requiring action. Using ultrasonic anemometers provides an accurate option for continuous air velocity monit...

objectives: scaling and root planing (srp) is one of the most commonly used procedures during periodontal treatment. the aim of this study was to evaluate the root surface roughness after srp with erbium: yttrium aluminum garnet (er:yag) laser compared to ultrasonic and hand instruments.   materials and methods: in this experimental study, 56 extracted sound single-rooted teeth with moderate le...

In this article, experimentally determined values of sound velocity in LPG in a temperature range (–23...+55) °C are presented. The measurements were taken using two industrial LPG samples in a standard five liter pressurized gas tank. The propagation time of a ultrasonic signal with the frequency of 0.7 MHz was measured. To increase the accuracy of measurement, a pulse-phase method was applied...

The overall objective of this work was to demonstrate feasibility of adaptive nonlinear signal processing techniques applied to characterization of ultrasonic nondestructive testing (UNDT) waveforms for accurate inferences of flat -bottom hole sizes. The classified waveforms were ultrasonic pulse echoes obtained from two different sets of 7075-T6 aluminum area-amplitude test blocks and three di...

In the construction industry, non–destructive testing (NDT) methods are often used in field to inspect compressive strength of concrete. NDT do not cause damage existing structure and relatively economical. Two popular rebound hammer (RH) test ultrasonic pulse velocity (UPV) test. One major drawback RH UPV is that concrete estimations very accurate when comparing them results obtained from dest...

The subject of the paper is simulation and measurements of an ultrasonic field in an isotropic homogeneous medium with attenuation. The complex problem of simultaneous influence of wave diffraction, attenuation, and velocity dispersion occurs. Only few publications can be mentioned on this subject. For example in [1] is presented an investigation of the complex problem of ultrasound field distr...

According to the shortcomings of the existing ultrasonic wind velocity measurement device, for instance, complexity of circuit and difficulty of signal processing, a new ultrasonic wind velocity measurement is put forward based on phase discrimination and a new sensor configuration as well. Thus, a system model is built. Firstly, an equilateral triangle should be constituted by an ultrasonic em...