Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quasi-periodic travelling waves for a class of damped beams on
  rectangular tori   This article concerns a class of beam equations with damping on rectangular
tori. When the generators satisfy certain relationship, by excluding some value
of two model parameters, we prove that such models admit small amplitude
quasi-periodic travelling wave solutions with two frequencies, which are
continuations of two rotating wave solutions with one frequency. This result
holds not only for an isotropic torus, but also for an anisotropic torus. The
proof is mainly based on a Lyapunov--Schmidt reduction together with the
implicit function theorem.

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The categories of this paper are: nlin
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The categories of this paper are: adap-org
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The categories of this paper are: plasm-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
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The categories of this paper are: stat
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The categories of this paper are: econ
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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: chao-dyn
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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: q-bio
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The categories of this paper are: q-fin
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The categories of this paper are: eess
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The categories of this paper are: cond-mat