Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: The influence of surface roughness on the rheology of immersed and dry
  frictional spheres
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys