Funding for this research was provided by:
Army Research Office (W911NF-15-1-0226)
Division of Mathematical Sciences (DMS-1418750)
China National Natural Science Foundation (11571367 11601536, 11601536)
Michigan Technological University
Research Excellence Fund Scholarship and Creativity Grant
Article History
Received: 17 October 2016
Revised: 23 December 2016
Accepted: 29 December 2016
First Online: 5 January 2017