Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An energy stable and positivity-preserving scheme for the Maxwell-Stefan
  diffusion system   We develop a new finite difference scheme for the Maxwell-Stefan diffusion
system. The scheme is conservative, energy stable and positivity-preserving.
These nice properties stem from a variational structure and are proved by
reformulating the finite difference scheme into an equivalent optimization
problem. The solution to the scheme emerges as the minimizer of the
optimization problem, and as a consequence energy stability and
positivity-preserving properties are obtained.

3
The categories of this paper are: physics
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
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The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an