**INVERSE SCATTERING **

**IN ACOUSTIC WAVEGUIDES**

**TRANSIENT PROBLEM** (wave equation)

Reconstruction of axisymmetric velocity

inhomogeneities from point source data

**FIXED-FREQUENCY INVERSE SCATTERING** (Helmholtz equation)

Global uniqueness for the refraction index from the DtN map

Complex geometric optics for waveguides

Reconstruction of hard obstacles in homogeneous wave guide

**Publications:**

1) G.N. Makrakis & M. Yamamoto, "A transient inverse scattering problem for acoustic waveguides",

Applicable Analysis, Vol. 69, pp. 285-302, 1998.

2) M. Ikehata, G.N. Makrakis & G. Nakamura, "Inverse boundary value problem in ocean acoustics",

Mathematical Methods in Applied Sciences, Vol. 24, pp. 1-8, 2001.

3) M. Ikehata, G.N. Makrakis & G. Nakamura, "Inverse boundary value problem for ocean acoustics using point sources",

to appear in: Mathematical Methods in Applied Sciences, 2003.

4) A.G. Ramm & G.N. Makrakis, "Scattering by obstacles in acoustic waveguides",

in Spectral and scattering theory (Ed. A.G. Ramm), Plenum, New York, 1998, pp. 89-110.

**Interesting related links:**

R.P. Gilbert, University of Delaware