Key;
Laboratory;
of;
Resources;
and;
Environment;
Information;
Engineering.;
China;
University;
of;
Mining;
&;
Technology,;
Xuzhou;
221;
?;
16,;
China;
School;
of;
Environment;
and;
Spatial;
Informatics,;
China;
University;
of;
Mining;
&;
Technology.;
Xuzhou;
221116,;
China;