^pof;
Information;
Science;
and;
Technology,;
Beijing;
Normal;
University,;
Beijing;
100875,;
China;
^pof;
Geography;
and;
Remote;
Sensing;
Beijing;
Normal;
University,;
Beijing;
100875,;
China;
^pof;
Remote;
Sensing;
Applications,;
Chinese;
Academy;
of;
Sciences,;
Beijing;
100101,;
China;