Wuenschel (1965) measured the attenuation of plate waves in a Plexiglas sheet, finding a value of (8.19X10-6+0.026)ft-1 for the attenuation coefficient at frequency (cps). Using only the first term in the attenuation, he then employed the results of Futterman (1962) to predict the intrinsic dispersion which should accompany this attenuation. Good agreement was obtained between the predicted and observed dispersion. Changes in pulse shape with distance traveled proved to be a sensitive indicator of the presence and nature of the dispersion; when pulses at a location remote from the source were predicted on the basis of a pulse observed near the source plus the transmission characteristics of the material, inclusion of the Futterman dispersion substantially improved the match between predicted and observed waveforms.

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