Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Adaptive Observers as Nonlinear Internal Models
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int