Funding for this research was provided by:
National Institute of Standards and Technology
Received: 17 January 2019
Accepted: 28 March 2019
First Online: 2 May 2019
: Dr. Ke used to be a Postdoctoral Research Associate at National Institute of Standards and Technology (NIST) and this study was done at NIST. Dr. Ke obtained his PHD degree of Aerospace Engineering at North Carolina State University. Currently Dr. Ke is working on aerodynamics in brushless motor as a research assistant at Department of Energy and Power Engineering of Tsinghua University.
: The author declares that he has no competing interests.
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