Results 1 to 10 of about 37 (34)
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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Air-Coupled Ultrasonic Spiral Phased Array for High-Precision Beamforming and Imaging
IEEE Open Journal of Ultrasonics, Ferroelectrics, and Frequency Control, 2022 Sparse spiral phased arrays are advantageous for many emerging air-coupled ultrasonic applications, since grating lobes are prevented without being constrained to the half-wavelength element spacing requirement of well-known dense arrays.
Gianni Allevato +6 more
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Electronic Architecture for Air Coupled Ultrasonic Pulse-Echo Range Finding with Application to Security and Surface Profile Imaging [PDF]
Universal Journal of Electrical and Electronic Engineering, 2014 Ultrasonic range finding instruments are utilized, e.g., for measuring liquid levels and distance to parking obstacles. However, instruments designed using the conventional electronic architectures to drive the ultrasonic transmitters cannot provide an operating range beyond a few meters for a flat solid wall with normal incidence when powered by a low
Sonbul, Omar, Kalashnikov, Alexander
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Nanotechnology and Precision Engineering, 2022 This paper proposes an air-coupled piezoelectric micromachined ultrasonic transducer (PMUT) for detection and imaging of surface stains. A 508 kHz PMUT array is designed, fabricated, and characterized in terms of its electrical and acoustic properties ...
Sheng Sun +3 more
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Sensors, 2023 An ultrasonic sonar-based ranging technique is introduced for measuring full-field railroad crosstie (sleeper) deflections. Tie deflection measurements have numerous applications, such as detecting degrading ballast support conditions and evaluating ...
Diptojit Datta +3 more
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Non-contact ultrasonic inspection by Gas-Coupled Laser Acoustic Detection (GCLAD)
Scientific Reports, 2022 Gas-Coupled Laser Acoustic Detection (GCLAD) is an ultrasonic, non-contact detection technique that has been recently proven to be applicable to the inspection of mechanical components.
Michelangelo-Santo Gulino +3 more
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Ferroelectret Ultrasonic Transducers for Pulse-Echo Water Immersion
Applied Sciences, 2020 Ferroelectrets are thin and porous polymeric films with a cellular microstructure, high porosity, permanent polarization and piezoelectric response.
Julio Quirce +3 more
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Air-Coupled Piezoelectric Transducers with Active Polypropylene Foam Matching Layers
Sensors, 2013 This work presents the design, construction and characterization of air-coupled piezoelectric transducers using 1–3 connectivity piezocomposite disks with a stack of matching layers being the outer one an active quarter wavelength layer made of ...
Tomás E. Gómez Alvarez-Arenas
doaj +1 more source
Ultrasound Flow-Monitoring and Flow-Metering of Air–Oil–Water Three-Layer Pipe Flows
IEEE Access, 2017 The combined use of ultrasound pulse-echo intensity and Doppler shift frequency is examined as a means to measure strong unsteady three-phase pipe flows of a gas and two liquids.
Junpei Hitomi +3 more
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Mechanical Engineering Journal, 2016 The fundamental study on the ultrasonic characterization of non-Gaussian rough surface of a material is carried out. In this study, a theoretical relationship among ultrasonic reflection coefficient at normal incidence, root mean square roughness Rq, and
Muhammad Nur Farhan SANIMAN, Ikuo IHARA
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