By using the way of drop dimensionality,this paper works out the integral representation of wave equation of two dimensionality Cauchy question from the viewpoint of Poisson formulas physics explaination and some examples are given to illustrate it.

This paper proposes a BEM computation model to calculate the transverse effective moduli and Poisson's ratios of unidirectional fiber reinforced composites.

The effect of interphase on transverse effective moduli and Poisson's ratios of the hexagonal-array unidirectional fiber reinforced composites are calculated by using the boundary element method.