Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Universal behaviors in granular flows and traffic flows   We review the current understanding on universal behaviors in granular flows
through a vertical pipe and traffic flows. We carry out weakly nonlinear
analysis of a model for traffic flows based on the technique of soliton
perturbations, and determine the selected propagating velocity, the amplitude,
the width of interfaces connecting between jam phase and non-jam phase. From
the direct simulation of the model, we have confirmed the validity of our
theoretical analysis. We also introduce a model for granular pipe flow
supplemented by the white noise, which reproduces $P(f)\sim f^{-4/3}$, where
$P(f)$ is the power spectrum in the frequency $f$.

20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int