Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Modelling attenuation and velocity of ultrasonics in reconstituted milk
  powder   In the context of food quality control, ultrasonics provide proven methods
which are able to replace manual controls. The latter are subject to the lack
of objectivity of human judgement. Automatic control increases reliability and
reduces costs. This paper revisits data coming from ultrasonics through
reconstituted milk powder. Two characteristics are studied using five
productions of a well known manufacturer. Measured attenuation and dispersion
of ultrasonics are explained through stable probability laws and random
propagation times. We have proved elsewhere that this model is available in
many propagation problems,in acoustics, ultrasonics and in the electromagnetic
world.

32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
4
The categories of this paper are: cond-mat