Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement theory of a density profile of small spheres on a
  cylindrical surface: Conversion of force curve measured with surface force
  apparatus into pressure on its surface element   Recently, in an ensemble of small spheres, we proposed a method that converts
the force between two large spheres into the pressure on the large sphere's
surface element. Using it, the density distribution of the small spheres around
the large sphere can be obtained experimentally. In a similar manner, in this
letter, we propose a transform theory for surface force apparatus, which
transforms the force acting on the cylinder into the density distribution of
the small spheres on the cylindrical surface. The transform theory we derived
is briefly explained in this letter.

6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
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The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
17
The categories of this paper are: q-fin