Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: RRV: A Spatiotemporal Descriptor for Rigid Body Motion Recognition   Motion behaviors of a rigid body can be characterized by a 6-dimensional
motion trajectory, which contains position vectors of a reference point on the
rigid body and rotations of this rigid body over time. This paper devises a
Rotation and Relative Velocity (RRV) descriptor by exploring the local
translational and rotational invariants of motion trajectories of rigid bodies,
which is insensitive to noise, invariant to rigid transformation and scaling. A
flexible metric is also introduced to measure the distance between two RRV
descriptors. The RRV descriptor is then applied to characterize motions of a
human body skeleton modeled as articulated interconnections of multiple rigid
bodies. To illustrate the descriptive ability of the RRV descriptor, we explore
it for different rigid body motion recognition tasks. The experimental results
on benchmark datasets demonstrate that this simple RRV descriptor outperforms
the previous ones regarding recognition accuracy without increasing
computational cost.

23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
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The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
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The categories of this paper are: dg-ga
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci