. 2015 Jan 29;15(2):2980–2998. doi: 10.3390/s150202980
© 2015 by the authors; licensee MDPI, Basel, Switzerland.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/http://creativecommons.org/licenses/by/4.0/).
Figure 13.
Spectral density of ambient vibration measurements.