Shanghai;
Astronomical;
Observatory,;
Chinese;
Academy;
of;
Sciences,;
Shanghai;
200030,;
China;
Shanghai;
Astronomical;
Observatory,;
Chinese;
Academy;
of;
Sciences,;
Shanghai;
200030,;
China;
Xi'an;
Research;
Institute;
of;
Surveying;
and;
Mapping,;
Xi'an;
710054,;
China;
Shanghai;
Astronomical;
Observatory,;
Chinese;
Academy;
of;
Sciences,;
Shanghai;
200030,;
China;
Xi'an;
Research;
Institute;
of;
Surveying;
and;
Mapping,;
Xi'an;
710054,;
China;