Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Proceedings 4th International Workshop on Engineering Safety and
  Security Systems
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph