Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Exploring Relay Cooperation Scheme for Load-Balance Control in Two-hop
  Secure Communication System
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph