Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Band-Gap Engineering of Phononic Crystals: A Computational Survey of
  Two-Dimensional Systems   We present graphic results with high-levels of abstraction to desribe the
basic principles and rules of thumb for acoustic or phononic band-gap
engineering. We use these rules for developing an improved machien mount for
damping acoustic vibrations, a phononic lens and a frequency selective filter
in the acoustic regime.

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The categories of this paper are: comp-gas
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The categories of this paper are: econ
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The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
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The categories of this paper are: stat
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat