Characterization of a cylindrical vibrating body in shallow water from partial measurement of its radiated field

The retrieval of the normal velocity of a time-harmonic vibrating body placed in shallow water is attempted from values of the radiated field on a vertical array R of hydrophones. The body is a cylinder of closed convex cross-section (circular, elliptic). The vibration is not assumed symmetric. Data on R may be noisy and inaccuracy on the receiver locations may be introduced. A boundary integral formulation of the wavefield is used and numerically dealt with via the efficient Nystrom method. The ill-posed linear inversion of the resulting system of boundary integral equations (BIE) is performed using filtered singular value decomposition (SVD) with a so-called L-curve criterion for the choice of a best Tikhonov´s parameter. Such a procedure provides good results though the one-sided aspect of the data and transmission in the bottom play a significant role