Results 1 to 10 of about 4,623,161 (291)
Air-Coupled and Resonant Pulse-Echo Ultrasonic Technique [PDF]
Sensors, 2019 An ultrasonic, resonant, pulse-echo, and air-coupled nondestructive testing (NDT) technique is presented. It is intended for components, with regular geometries where it is possible to excite resonant modes, made of materials that have a high acoustic ...
Tomás Gómez Álvarez-Arenas +1 more
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Deep-Subwavelength-Optimized Holey-Structured Metamaterial Lens for Nonlinear Air-Coupled Ultrasonic Imaging [PDF]
Sensors, 2021 Ultrasound non-destructive testing (NDT) is a common technique used for defect detection in different materials, from aluminium to carbon-fiber-reinforced polymers (CFRPs).
Marco Boccaccio +4 more
doaj +2 more sources
Air-Coupled Photoacoustic Detection of Airborne Particulates [PDF]
International Journal of Thermophysics, 2023 <p>In this study, we present a novel method to detect airborne particulates using air-coupled photoacoustics, with a goal toward detecting viral content in respiratory droplets. The peak photoacoustic frequency emitted from micrometer-sized particulates is over 1000 MHz, but at this frequency, the signals are highly attenuated in air ...
Strohm, Eric M. +4 more
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Air-Coupled Ultrasonic Inspection of Foods: A Review
IEEE Open Journal of Ultrasonics, Ferroelectrics, and Frequency ControlIn the context of the ongoing digital revolution, the food industry grapples with significant challenges concerning quality control, safety, production efficiency, and economic viability.
Anabella Giacomozzi +3 more
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IEEE Open Journal of Ultrasonics, Ferroelectrics, and Frequency Control, 2022 Data-over-sound is an emerging technology for digital communication which uses frequencies at the upper bounds of human hearing, usually between 15 kHz to 25 kHz.
Harshvardhan Gupta +3 more
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Sea ice thickness from air-coupled flexural waves [PDF]
The Cryosphere, 2021 Air-coupled flexural waves (ACFWs) appear as wave trains of constant frequency that arrive in advance of the direct air wave from an impulsive source travelling over a floating ice sheet. The frequency of these waves varies with the flexural stiffness of
R. Romeyn +4 more
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Theory of Air-Coupled Flexural Waves [PDF]
Journal of Applied Physics, 1951 The theory of air-coupled flexural waves in a floating ice sheet is derived for the case of an impulsive point source situated either in the air or in the water. It is found that new branches are introduced to the dispersion curve of flexural waves as a result of coupling to compressional waves in the atmosphere. Experimental data are briefly reviewed.
Press, Frank, Ewing, Maurice
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Phased array probes for air-coupled ultrasonic testing based on cellular polymer
Research and Review Journal of Nondestructive Testing, 2023 Air-coupled ultrasonic testing is an established alternative to conventional ultrasonic methods for testing of light-weight components in aerospace and automotive industry.
Mate Gaal +6 more
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Air-Coupled Ultrasonic Ferroelectret Receiver with Additional DC Voltage
Proceedings, 2017 Highly sensitive air-coupled ultrasonic sensors are essential for various applications such as testing of composite materials. One of the major challenges for the development of air-coupled ultrasonic sensors is the impedance matching to air.
Mate Gaal +3 more
doaj +1 more source
Application of Micro-Electro-Mechanical Sensors Contactless NDT of Concrete Structures
Sensors, 2015 The utility of micro-electro-mechanical sensors (MEMS) for application in air-coupled (contactless or noncontact) sensing to concrete nondestructive testing (NDT) is studied in this paper.
Suyun Ham, John S. Popovics
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