^pSchool;
in;
Northeast;
Normal;
University,;
Changchun;
130024,;
PRC;
^pTechnology;
Research;
Laboratory,;
De;
Montfort;
University,;
Leicester;
LE1;
9BH,;
UK;
^pof;
Ideal;
Information;
and;
Technology;
in;
Northeast;
Normal;
University,;
Changchun;
130024,;
PRC;
^pResearch;
Center;
of;
E-Learning;
Technologies,;
Ministry;
of;
Education,;
Changchun;
130024,;
PRC;