Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Development of In Situ Acoustic Instruments for The Aquatic Environment
  Study   Based on the analysis of existing acoustic methods and instruments, a
prototype of an automated instrument has been developed to perform joint
measurements in situ of two parameters: sound speed and ultrasound attenuation.
The device is based on existing sound velocity profilers. It was proposed to
replace the TDC-GP22 converters used in the sound speed meter ISZ-1 with more
advanced modern modified converters TDC-GP30, which can significantly improve
the accuracy of measuring the amplitude of the reflected acoustic signal. The
programs for processing signals from the primary acoustic transducer have been
developed. The model of the device passed preliminary tests.

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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom