Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Existence of weak solutions for a nonlocal pseudo-parabolic model for
  Brinkman two-phase flow in asymptotically flat porous media   We study a nonlocal evolution equation that involves a pseudo-parabolic
third-order term. The equation models almost uni-directional two-phase flow in
Brinkman regimes. We prove the existence of weak solutions for this equation.
We also give a series of numerical examples that demonstrate the ability of the
equation to support overshooting and explore the behavior of solutions in
various limit regimes.

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The categories of this paper are: astro-ph
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
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The categories of this paper are: q-bio
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The categories of this paper are: quant-ph
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
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The categories of this paper are: mtrl-th
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The categories of this paper are: physics
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: nlin
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The categories of this paper are: chem-ph
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The categories of this paper are: eess