Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Modified Szabo's wave equation models for lossy media obeying frequency
  power law   Szabo's models of acoustic attenuation (Szabo 1994a) comply well with the
empirical frequency power law involving non-integer and odd integer exponent
coefficients while guaranteering causality, but nevertheless encounter the
troublesome issues of hyper-singular improper integral and obscurity in
implementing initial conditions. The purpose of this paper is to ease or remove
these drawbacks of the Szabo's models via the Caputo fractional derivative
concept. The positive time fractional derivative is also first introduced to
include the positivity of the attenuation possesses.

11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
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
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph