Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An Expedient Approach to FDTD-based Modeling of Finite Periodic
  Structures   This paper proposes an efficient FDTD technique for determining
electromagnetic fields interacting with a finite-sized 2D and 3D periodic
structures. The technique combines periodic boundary conditions---modelling
fields away from the edges of the structure---with independent simulations of
fields near the edges of the structure. It is shown that this algorithm
efficiently determines the size of a periodic structure necessary for fields to
converge to the infinitely-periodic case. Numerical validations of the
technique illustrate the savings concomitant with the algorithm.

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The categories of this paper are: eess
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The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
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The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
15
The categories of this paper are: nucl-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio