Funding for this research was provided by:
National Science Foundation (ATM-1242815)
Air Force Office of Scientific Research (FA9550-15-0018)
Text and Data Mining valid from 2018-04-18
Received: 28 September 2017
Accepted: 20 March 2018
First Online: 18 April 2018
: The authors declare that they have no competing interests.
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