Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exact Boundary Observability and Controllability of the Wave Equation in
  an Interval with two Moving Endpoints   We study the wave equation in an interval with two linearly moving endpoints.
We give the exact solution by a series formula, then we show that the energy of
the solution decay at the rate $1/t$. We also establish observability results,
at one or two endpoints, in a sharp time. Moreover, using the Hilbert
uniqueness method, we derive exact boundary controllability results.

20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con