Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Crackling noise in paper peeling   Acoustic emission or crackling noise is measured from an experiment on
splitting or peeling of paper. The energy of the events follows a power-law,
with an exponent $\beta \sim 1.8\pm 0.2$. The event intervals have a wide
range, but superposed on scale-free statistics there is a time-scale, related
to the typical spatial scale of the microstructure (a bond between two fibers).
Since the peeling takes place via steady-state crack propagation, correlations
can be studied with ease and shown to exist in the series of acoustic events.

13
The categories of this paper are: quant-ph
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The categories of this paper are: eess
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
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The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph