Funding for this research was provided by:
National Space Organization (NSPO-S-108002)
Ministry of Science and Technology, Taiwan (MOST-107-2119-M-006-003)
Text and Data Mining valid from 2019-02-04
Received: 11 July 2018
Accepted: 21 January 2019
First Online: 4 February 2019
: The authors declare that they have no competing interests.
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