Scattering of electromagnetic waves by many thin cylinders
  Electromagnetic wave scattering by many parallel infinite cylinders is studied asymptotically as $a\to 0$. Here $a$ is the radius of the cylinders. It is assumed that the points $\hat{x}_m$ are distributed so that $\mathcal{N}(\Delta)=\frac{1}{a}\int_{\Delta}N(x)dx[1+o(1)], $ where $\mathcal{N}(\Delta)$ is the number of points $\hat{x}_m=(x_{m1},x_{m2})$ in an arbitrary open subset of the plane $xoy$, the axes of the cylinders are passing through points $\hat{x}_m$, these axes are parallel to the z-axis. The function $N(x)\geq 0$ is a given continuous function. An equation for the self-consistent (efficient) field is derived as $a\to 0$. The cylinders are assumed perfectly conducting. Formula is derived for the effective refraction coefficient in the medium in which many cylinders are distributed. 
Alexander G. Ramm
math-ph cond-mat.mes-hall math.MP