Welding high-strength aluminium alloys is generally a delicate operation due to the degradation of mechanical properties in thermally affected zone (TAZ) and presence porosities molten metal. Furthermore, contain compounds that solidify before rest base alloy, therefore acting as stress concentration points lead phenomenon hot cracking. This paper investigates process applying ultrasonic vibrat...

This chapter first presents a review of existing locomotion assistance devices for the blind. These devices are merely proximeters, that measure the distance to the closest obstacles, and convey this information to their users. We introduce the measurement methods (infrared sensors, ultrasonic sensors, laser telemeters) and the user interfaces (sounds and tactile vibrations). Then, we analyse t...

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A method and mathematical models of direct inverse problems ultrasonic testing diagnostics complex metal structures for defects were developed tested. prototype a system magnetostrictive control elements the objects under study was manufactured experimentally Mathematical simulation processes using MATLAB COMSOL Multiphysics software environment carried out. The adequacy verified by results the...

Soft tissues surrounding vascular injuries are known to vibrate at audible and palpable frequencies, producing bruits and thrills. We report the results of a feasibility study where Doppler ultrasound (US) was used to quantitatively estimate the tissue vibrations after induced trauma in an animal model. A software-programmable US system was used to acquire quadrature-demodulated ensembles of re...

Arterial bleeding into a free space is known to cause local vibrations in tissue. To study the effectiveness of utilizing these tissue vibrations in localizing the site of arterial bleeding, we have developed an algorithm for ultrasonically imaging these tissue vibrations. Simulation results indicate that our algorithm can correctly detect vibrations in the presence of pulsatile wall motion, bl...