Results 201 to 210 of about 141,866 (259)
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IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 1998
Lamb waves are extensively involved in plate structure inspection because of their guided nature. However, their dispersive nature often limits their use in flaw detection. In this paper we show that the use of a time-reversal mirror (TRM) allows to automatically compensate for the dispersive nature of Lamb waves.
R K, Ing, M, Fink
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Lamb waves are extensively involved in plate structure inspection because of their guided nature. However, their dispersive nature often limits their use in flaw detection. In this paper we show that the use of a time-reversal mirror (TRM) allows to automatically compensate for the dispersive nature of Lamb waves.
R K, Ing, M, Fink
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IEEE Symposium on Ultrasonics, 2002
Tomographic imaging of the condition of tin materials has been performed using Lamb waves. Lamb waves were generated in thin sheets of aluminum submerged in water using an immersion transducer set at the critical angle. An identical transducer at a fixed separation detected energy radiated back into the water by the propagating Lamb wave.
D.P. Jansen, D.A. Hutchins
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Tomographic imaging of the condition of tin materials has been performed using Lamb waves. Lamb waves were generated in thin sheets of aluminum submerged in water using an immersion transducer set at the critical angle. An identical transducer at a fixed separation detected energy radiated back into the water by the propagating Lamb wave.
D.P. Jansen, D.A. Hutchins
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Ultrasonic Lamb wave diffraction tomography
Ultrasonics, 2001Ultrasonic guided waves, Lamb waves, allow large sections of aircraft structures to be rapidly inspected. Unlike conventional ultrasonic C-scan imaging that requires access to the whole inspected area, tomographic algorithms work with data collected over the perimeter.
E V, Malyarenko, M K, Hinders
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Lamb Wave Multitouch Ultrasonic Touchscreen
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2016Touchscreen sensors are widely used in many devices such as smart phones, tablets, and laptops with diverse applications. We present the design, analysis, and implementation of an ultrasonic touchscreen system that utilizes the interaction of transient Lamb waves with objects in contact with the screen. It attempts to improve on the existing ultrasound
Kamyar Firouzi +3 more
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Air-coupled Lamb wave tomography
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 1997An entirely air-coupled inspection system using a pair of micromachined silicon capacitance transducers has been used to image defects in thin plates of different materials (0.7 mm to 2.22 mm thick) using air-coupled Lamb wave tomography. A filtered back projection algorithm was used in a form of difference tomography to reconstruct images of defects ...
W, Wright +3 more
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Internal Antisymmetric Lamb Waves
Акустический журнал, 2023A class of antisymmetric solutions of Lamb wave equations with zero strains and stresses on the surface, so-called internal Lamb waves, is studied. Two types of such solutions are found: the first corresponds to the Lamé phase velocity; the second, to phase velocities exceeding the velocity of the expansion wave in an unbounded medium.
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LAMB WAVES IN A POROELASTIC PLATE
Journal of Computational Acoustics, 2013In this paper we consider the propagation of Lamb waves in a poroelastic plate containing a linear crack, the special case where the surface of the plate is unloaded, by employing the Wiener-Hopf technique. The problem we solve here is a mathematically interesting toy problem. Physically speaking the more reasonable problem would be to consider there
Gilbert, Robert P. +2 more
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Long-Wave Asymptotics of Lamb Waves
Mechanics of Solids, 2017The six-dimensional complex formalism is used to obtain equations for determining long-wave asymptotics of symmetric fundamental modes of Lamb waves in an anisotropic layer. Analytic expressions are obtained for long-wave asymptotics of phase velocities of Lamb waves propagating in an isotropic layer.
R. V. Goldstein, S. V. Kuznetsov
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Journal of Applied Mathematics and Mechanics, 2009
The author presents results of an analysis of the velocity and the polarization of acoustic Lamb waves propagating in the directions of elastic symmetry of one- and two-layer anisotropic media at small vanishing frequencies (soliton-like waves). The method of fundamental matrices is used for the construction of a solution.
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The author presents results of an analysis of the velocity and the polarization of acoustic Lamb waves propagating in the directions of elastic symmetry of one- and two-layer anisotropic media at small vanishing frequencies (soliton-like waves). The method of fundamental matrices is used for the construction of a solution.
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Generalized Lamb-wave multisensor
IEEE 1988 Ultrasonics Symposium Proceedings., 2003Integrated-circuit fabrication techniques were used to make a versatile silicon-based sensor that uses elastic wave propagation in a plate that is thin compared with the wavelength. In-plane tension raises the velocity of the lowest antisymmetric flexural wave (474 m/s) above that predicted for a pure Lamb wave (422 m/s).
S.W. Wenzel, B.A. Martin, R.M. White
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