Exploiting the fine structure of strongly scattered surface waves could provide a wealth of new information in seismology, ultrasonics, acoustics and other fields that study wave propagation in highly heterogeneous media. Toward this end, we have made laboratory measurements of ultrasonic waves propagating in disordered media. Spectral-element simulations of these models provide us with a power...

the interpolated retrograde P waves, the retrograde limb of a SAN reentry in the SAN junction probably would also have been blocked. Therefore, it’s highly unlikely the NPs occur as a result of SAN reentry with a failure to depolarize the left atrium. However, the NPs may represent right atrial depolarizations in left atrial P waves originating near the left atrial termination of BB (Fig 82) wh...

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...