Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Seismic Negative Belt of Acoustic Metamaterials   An earthquake-proof seismic negative belt of an artificial seismic shadow
zone is introduced. The belt is composed of acoustic materials which has one of
the constituent parameter between density and modulus is negative effectively.
It converts the velocity of the seismic wave imaginary, and then creates a
stop-band for the seismic frequency range. The belt is an attenuator of a
seismic wave that reduces the amplitude of the wave exponentially. Passing the
belt underground, the seismic energy turns into sound and heat in air and the
magnitude of the seismic wave is weakened to be defended by conventional
method. Models of the negative density and negative modulus for engineering are
suggested.

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The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
18
The categories of this paper are: econ
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
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The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ph
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn