1. The estimation of the phase velocity of the elastic waves based on the transfer matrix method for binary systems Nicoleta Popescu-Pogrion-INCDFM Bucuresti Ionel Mercioniu-INCDFM Bucuresti Nicolae Cretu –Univ. Transilvania Brasov

2. Transfer matrix method

3. The equivalent medium

4. Equivalent matrices The matrix T(ω) has the eigenvalues: The matrix T’(ω) has the eigenvalues:

5. Effective velocity

6. Numeric estimation

7. The zero’ estimation of g(x)

8. Error estimation The behaviour of c 2 around f exp. The vertical bars show the range of values of c 2 around c 2exp obtained for deviations of f around f exp. The maximum relative deviations of f are shown above the vertical bars.

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