Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non Linear Techniques for Increasing Harvesting Energy from
  Piezoelectric and Electromagnetic Micro-Power-Generators   Non-linear techniques are used to optimize the harvested energy from
piezoelectric and electromagnetic generators. This paper introduces an
analytical study for the voltage amplification obtained from these techniques.
The analytical study is experimentally validated using a macro model of
piezoelectric generator. Moreover, the integration influences on these
techniques is studied. Through all the obtained results, a suitable structure
for autonomous microsystems is proposed.

35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ