Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Toward Traffic Patterns in High-speed Railway Communication Systems:
  Power Allocation and Antenna Selection
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga