Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Taking drift-diffusion analysis from the study of turbulent flows to the
  study of particulate matter smog and air pollutants dynamics   Drift-diffusion analysis has been introduced in physics as a method to study
turbulent flows. In the current study, it is proposed to use the method to
identify underlying dynamical models of particulate matter smog, ozone and
nitrogen dioxide concentrations. Data from Chiangmai are considered, which is a
major city in the northern part of Thailand that recently has witnessed a
dramatic increase of hospitalization that are assumed to be related to extreme
air pollution levels. Three variants of the drift-diffusion analysis method
(kernel-density, binning, linear approximation) are considered. It is shown
that all three variants explain the annual pollutant peaks during the first
half of the year by assuming that the parameters of the physical-chemical
evolution equations of the pollutants vary periodically throughout the year.
Therefore, our analysis provides evidence that the underlying dynamical models
of the three pollutants being considered are explicitly time-dependent.

7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph