The present work addresses the ultrasonic NDT of rails, more precisely rail foot. practical constraint is that transducers must be located on head, whereas region interest Thus, there no direct acoustic path between and interest. As classical delay sum methods cannot applied to such cases, goal paper numerically assess potentiality topological imaging method investigate Three specific typical f...

We have previously introduced an ultrasonic imaging approach that combines harmonic-sensitive pulse sequences with a post-beamforming quadratic kernel derived from a second-order Volterra filter (SOVF). This approach is designed to produce images with high sensitivity to nonlinear oscillations from microbubble ultrasound contrast agents (UCA) while maintaining high levels of noise rejection. In...

Abstruct-A very small transmiffreceiver chip has been developed for use in an arterial ultrasonic imaging system. In this technique, a solid-state ultrasonic imaging head placed within a small medical catheter is used to provide high quality 360" images of arteries as small as 2 mm in diameter. Novel design and packaging techniques have been used to allow four easily testable 0.86 mm x 1.65 mm ...

Achieving label-free, molecular-specific imaging with high spatial resolution in deep tissue is often considered the grand challenge of optical imaging. To accomplish this goal, significant optical scattering in tissues has to be overcome while achieving molecular specificity without resorting to extrinsic labeling. We demonstrate the feasibility of developing such an optical imaging modality b...

Photoacoustic tomography, also referred to as optoacoustic tomography, employs short laser pulses to generate ultrasonic waves in biological tissues. The reconstructed images can be characterized by the convolution of the structure of samples, the laser pulse and the impulse response of the ultrasonic transducer used for detection. Although the laser-induced ultrasonic waves cover a wide spectr...

Medical imaging is concerned with the development of the imaging devices that help to identify different aspects of the tissue and organs based on various properties and reveal new properties of the tissue and internal structure. Ultrasonic devices are frequently used for medical imaging and the images produced by these devices often have to be converted to a form that is better suited for imag...

Ultrasonic measurements have been performed for comprehensive microstructural characterisation in 9 % Cr ferritic steels. The variation in grain size, the effect of solution annealing temperature on microstructure developed, the variation in microstructure of the weld joints, the effect of post weld heat treatment and precipitation behaviour during thermal ageing and creep testing have been suc...