1. National Engineering Research Center for E-Learning, Central China Normal University, Wuhan, People's Republic of China
2. School of Media and Technology, Liaocheng University, Liaocheng, People’s Republic of China
3. School of Computer Science, Wuhan University, Wuhan, People’s Republic of China
4. School of Teacher Education, Huzhou University, Huzhou, People’s Republic of China
5. Key Laboratory of Child Development and Learning Science, Ministry of Education, Research Center for Learning Science, Southeast University, Nanjing, People’s Republic of China