Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Optimal Control to Handle Variations in Biomass Feedstock
  Characteristics and Reactor In-Feed Rate
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
9
The categories of this paper are: nlin