Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Persistence analysis of the age-structured population model on several
  patches   We consider a system of nonlinear partial differential equations that
describes an age-structured population living in changing environment on $N$
patches. We prove existence and uniqueness of solution and analyze large time
behavior of the system in time-independent case, for periodically changing and
for irregularly varying environment. Under the assumption that every patch can
be reached from every other patch, directly or through several intermediary
patches, and that net reproductive operator has spectral radius larger than
one, we prove that population is persistent on all patches. If the spectral
radius is less or equal one, extinction on all patches is imminent.

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The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics