Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Short-time dynamics of a packing of polyhedral grains under horizontal
  vibrations   We analyze the dynamics of a 3D granular packing composed of particles of
irregular polyhedral shape confined inside a rectangular box with a retaining
wall sub jected to horizontal harmonic forcing. The simulations are performed
by means of the contact dynamics method for a broad set of loading parameters.
We explore the vibrational dynamics of the packing, the evolution of solid
fraction and the scaling of dy- namics with the loading parameters. We show
that the motion of the retaining wall is strongly anharmonic as a result of
jamming and grain rearrangements. It is found that the mean particle
displacement scales with inverse square of frequency, the inverse of the force
amplitude and the square of gravity. The short- time compaction rate grows in
proportion to frequency up to a characteristic frequency, corresponding to
collective particle rearrangements between equilibrium states, and then it
declines in inverse proportion to frequency.

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The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int