Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Group Analysis of Variable Coefficient Diffusion-Convection Equations.
  II. Contractions and Exact Solutions   This is the second part of the series of papers on symmetry properties of a
class of variable coefficient (1+1)-dimensional nonlinear diffusion-convection
equations of general form $f(x)u_t=(g(x)A(u)u_x)_x+h(x)B(u)u_x$. At first, we
review the results of Part 1 of the series on equivalence transformations and
group classification of the class under consideration. Investigation of
non-trivial limits of parameterized subclasses of equations from the given
class, which generate contractions of the corresponding maximal Lie invariance
algebras, leads to the natural notion of contractions of systems of
differential equations. After a brief discussion on contractions of symmetries,
equations and solutions in general case, such types of contractions are studied
for diffusion--convection equations. A detailed symmetry analysis of an
interesting equation from the class under consideration is performed. Exact
solutions of some subclasses of the considered class are also given.

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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: physics
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The categories of this paper are: eess
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The categories of this paper are: patt-sol
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The categories of this paper are: quant-ph
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The categories of this paper are: q-alg
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The categories of this paper are: plasm-ph
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The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
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The categories of this paper are: chem-ph