Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An application of the catastrophe theory to building the model of
  elastic-plastic behaviour of materials. An application of the catastrophe
  theory to building the model of elastic-plastic behaviour of materials. Part
  1. Uniaxial deformation (stress)   The uniaxial elastic-plastic deformation process is considered. Mathematical
model of this process was built. According to this model all stable static
states form the lattice, which is called the delta-lattice.

13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th