http://reply.papertrans.cn/1/90/8958/8958-11.png
http://reply.papertrans.cn/1/90/8958/8958-12.png
Submitted on: 07 November 2012.
Revised on: 01 January 2013.
Accepted on: 20 January 2013.
___________________ETR&D-EDUCATIONAL TECHNOLOGY RESEARCH AND DEVELOPMENT
Submitted on: 26 March 2002.
Revised on: 16 April 2002.
Accepted on: 14 June 2002.
___________________ETR&D-EDUCATIONAL TECHNOLOGY RESEARCH AND DEVELOPMENT
http://reply.papertrans.cn/1/90/8958/8958-15.png
Submitted on: 11 July 2008.
Revised on: 14 August 2008.
Accepted on: 13 September 2008.
___________________ETR&D-EDUCATIONAL TECHNOLOGY RESEARCH AND DEVELOPMENT
http://reply.papertrans.cn/1/90/8958/8958-17.png
Submitted on: 16 December 2016.
Revised on: 04 February 2017.
Accepted on: 27 March 2017.
___________________ETR&D-EDUCATIONAL TECHNOLOGY RESEARCH AND DEVELOPMENT
http://reply.papertrans.cn/1/90/8958/8958-19.png
http://reply.papertrans.cn/1/90/8958/8958-20.png