Results 221 to 230 of about 13,079 (259)

Nonlinear ultrasonic imaging of imperfectly bonded interfaces

Ultrasonics, 2006
A nonlinear ultrasonic imaging system is developed for detecting and imaging damages and defects with nm order gaps in industrial materials, which were undetectable by conventional ultrasonic imaging systems. A high power pulser generating large amplitude incident waves and high gain receiver with high-pass or band-pass filters extracting the second ...
Koichiro, Kawashima, Morimasa, Murase, Ryuzo, Yamada, Masamichi, Matsushima, Mituyoshi, Uematsu, Fumio, Fujita   +5 more
openaire   +2 more sources

Nonlinear explanation for bone-conducted ultrasonic hearing

Hearing Research, 2005
Human listeners can perceive speech from a voice-modulated ultrasonic carrier presented via a bone-conduction stimulator. This study explored the psychoacoustic characteristics and underlying mechanisms of ultrasonic hearing by measuring difference limens for frequency (DLF) for pure tones modulated onto ultrasonic carriers.
Kiyoshi, Fujimoto, Seiji, Nakagawa, Mitsuo, Tonoike   +2 more
openaire   +2 more sources

Ultrasonic characterization of the nonlinear properties of contrast microbubbles

Ultrasound in Medicine & Biology, 2000
The nonlinear properties of microbubble contrast agents have been used to create contrast-specific imaging modalities such as harmonic imaging and subharmonic imaging. Thus, a better understanding of the nonlinear performance of contrast microbubbles may enhance the diagnostic capabilities of medical ultrasound (US) imaging.
W T, Shi, F, Forsberg
openaire   +2 more sources

Overview—Nonlinear Ultrasonic Characteristics

2020
Nonlinear ultrasonic characteristics are the features that result from the nonlinear interactions between the propagating ultrasonic waves and the material or defects, which typically include higher harmonic generation, sub-harmonic generation, nonlinear resonance and nonlinear frequency-mixing.
openaire   +1 more source

Dependence of Ultrasonic Nonlinear Parameter B/A on Fat

Ultrasonic Imaging, 1987
This study deals with the relationship between the magnitude of acoustic nonlinearity, sound speed of tissues and the amount of fat present in them. A two-component model, i.e., nonfat and fat, has been assumed and equations that relate the nonlinear parameter (B/A) of a medium to the properties of its components have been derived for two cases. In the
R L, Errabolu, C M, Sehgal, J F, Greenleaf   +2 more
openaire   +2 more sources

Nonlinear ultrasonic phase-conjugate beams and their application in ultrasonic imaging

Acoustical Physics, 2004
The latest results of experimental and theoretical research into phase conjugation of nonlinear ultrasonic beams are generalized, and prospects for the development of nonlinear ultrasonic imaging are outlined.
Brysev, Andrey, Krutyansky, Leonid, Pernod, Philippe, Preobrazhensky, Vladimir L.   +3 more
openaire   +2 more sources

Ultrasonic nonlinear parameter CT using nonlinear interaction of sound waves

Systems and Computers in Japan, 1987
AbstractThis paper proposes a new ultrasonic CT using the nonlinear interaction between two ultrasonic waves. Two finite‐amplitude waves with different frequencies are radiated along the same axis in the same direction as the primary waves. The secondary wave produced at the difference frequency is measured as the projection data to reconstruct the ...
Yoshikatsu Nakagawa, Masao Nakagawa, Masahide Yoneyama, Makoto Kikuchi   +3 more
openaire   +1 more source

MIMO Nonlinear Ultrasonic Tomography by Propagation and Backpropagation Method

IEEE Transactions on Image Processing, 2013
This paper develops a fast ultrasonic tomographic imaging method in a multiple-input multiple-output (MIMO) configuration using the propagation and backpropagation (PBP) method. By this method, ultrasonic excitation signals from multiple sources are transmitted simultaneously to probe the objects immersed in the medium.
Chengdong Dong, Yuanwei Jin
openaire   +2 more sources

Modeling of the ultrasonic nonlinear propagation with VHDL-AMS.

2003
In this paper we present an electronic measurement instrumentation developed in our laboratory, to measure and plot the impedance of the fuel cell (FC) on load, using the load modulation method.This instrumentation has been developed around a VXI system stand which controls electronic cards. Software under HPVEE® automate measurements and layout.
Guelaz, Rachid, Kourtiche, Djilali, Herve, Yannick, Nadi, Mustapha   +3 more
openaire   +3 more sources

Nonlinear ultrasonic inspection of friction stir welds

2015
Nonlinear ultrasonic approach combined with pulse inversion method is applied for interpretation of the damage status of kissing bonds contacts in friction stir welds.
Tabatabaeipour M., Hettler J., Delrue S., Van Den Abeele K.   +3 more
openaire   +1 more source