| Autor: |
Commander, Kerry W., McDonald, Robert J. |
| Zdroj: |
Journal of the Acoustical Society of America; 1990, Vol. 87 Issue S1, pS54-S55, 2p |
| Abstrakt: |
The determination of acoustic bubble spectra in the ocean from multi-frequency attenuation measurements was improved by numerical solution of the inverse scattering problem [K. W. Commander and E. Mortiz, in Proceedings of IEEE Oceans '89, 1181-1185 (1989)]. Although this numerical solution offers an improvement over the resonance approximation (at small radii), it too suffers a loss of accuracy at the small radii end of the bubble spectrum. The numerical solution of this problem has been improved by replacing the Fourier series approximation to the unknown distribution by a piecewise linear polynomial constructed from a series of basis functions. The basis functions used were linear B-splines or 'hat' functions. The resulting coefficient matrices are much less ill-conditioned than those from the previous method because of the local support of the basis functions. This improvement leads to a more accurate solution of the inverse scattering problem near the end points. Improvements in accuracy due to the finite element solution are quantified using calculated attenuations from several bubble distributions of interest. [Work supported by ONT.] [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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