Results 281 to 290 of about 643,568 (346)

Vibro-Acoustography: Speckle Free Ultrasonic C-Scan

2002
In an in vitro experiment the acoustic emission characteristics of broken and intact struts on BSCC valves exhibited different frequency responses and different vibro-acoustography images. The images indicated that the vibration modes of the object could be deduced in addition to the structural integrity of the object.
James F. Greenleaf, Mostafa Fatemi, Randall R. Kinnick   +2 more
openaire   +1 more source

Neural network-based ultrasonic C-scan imaging of austenitic structures

The Journal of the Acoustical Society of America, 1999
Results of new studies of C-scan imaging on austenitic welds, used in conjunction with artificial neural network techniques, are reported. The C-scan technique provides high-resolution images of subsurface zones which are inaccessible by conventional A-scans.
Petre Petculescu, Dorin Ciobanu
openaire   +1 more source

Ultrasonic C-scan evaluation of Ti-alloy/Al brazed joint

AIP Conference Proceedings, 2013
An indigenously developed brazed joint of Al/Ti was characterized by ultrasonic C-scan method. The study revealed certain debond locations in the brazed joint. These debond locations would have resulted due to the failure of filler material’s joining ability.
G. V. S. Murthy, G. Sridhar
openaire   +1 more source

C-scan imaging in molten zinc by focused ultrasonic waves

The Journal of the Acoustical Society of America, 2000
Ultrasonic images of a small steel object immersed in molten zinc at 600 °C are obtained with high spatial resolution using a focused ultrasonic pulse-echo technique. The focused ultrasonic waves are generated by a spherical acoustic lens which has been machined at the probing end of a clad buffer rod.
, Ihara, , Jen, , Franca
openaire   +2 more sources

Ultrasonic C-Scan Standardization for Polymer-Matrix Composites - Acoustic Considerations

1998
Ultrasonic C-scan inspection techniques are widely used for the non-destructive evaluation of fiber-reinforced polymer composites. A C-scan is any two-dimensional scan of a specimen that produces a map of a parameter, such as reflected amplitude, as it varies across the surface of the specimen.
Smith, Robert A, Bruce, David A, Jones, Lyn D, Marriott, Adam B, Scudder, Lawrence P, Willsher, Stephen J   +5 more
openaire   +2 more sources

Blind image restoration for ultrasonic C-scan using constrained 2D-HOS

2001 IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings (Cat. No.01CH37221), 2002
A new approach is presented to use higher order statistics (HOS) to deconvolve the effects of blurring in ultrasonic C-scans. The quantization effects of the mechanical scan-grid and the conversion of the 1D A-scan into one pixel on the image cause blurring.
U. Qidwai, null Chi-Hau Chen
openaire   +1 more source

Synthetic axial acquisition-full resolution, low-cost C-scan ultrasonic imaging

IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2008
The synthetic axial acquisition (SAA) approach presented here is designed to produce C-scan images using low-cost, low bandwidth, front end electronics. We exploit plane wave transmission and shallow C-scan imaging of non-moving, or slowly moving, tissue regions.
null Yinbo Li, T.N. Blalock, J.A. Hossack   +2 more
openaire   +1 more source

Comparison of acoustgraphy, ultrasonic spectroscopy, and c-scan ultrasonics as applied to the composite flywheels

SPIE Proceedings, 2003
The replacement of chemical batteries with composite flywheels offers many potential advantages in space applications. Before such flywheels can be successfully employed, it is imperative to ensure their integrity using NDE techniques. Previously, the use of traditional C-scan for the NDE of flywheels was compared to Scanning Ultrasonic Spectroscopy ...
Honghui Wang, Richard E. Martin, George Y. Baaklini, Jaswinder S. Sandhu   +3 more
openaire   +1 more source

Improving Ultrasonic C-Scan Resolution Using the Hilbert-Huang Transform

AIP Conference Proceedings, 2005
The Hilbert Huang Transform (HHT) is applied to ultrasonic mapping of simulated defects in an aluminum plate. C‐Scanning tests are conducted using pulse‐echo ultrasound on a water‐immersed aluminum plate containing a matrix of 16 unevenly‐spaced flat‐bottomed holes.
openaire   +1 more source

Ultrasonic C-scan Image Restoration Using Radial Basis Function Network

2004
A method for restoration of ultrasonic C-scan images is presented by using a radial basis function network. The method attempts to reproduce the mapping between the degraded C-scan image and the high quality one by training a RBF network. The inputs for training are the sub-images divided from C-scan image of flat-bottom hole of size 3mm and the output
Zongjie Cao, Huaidong Chen, Jin Xue, Yuwen Wang   +3 more
openaire   +1 more source