Submitted on: 12 February 2006.
Revised on: 10 June 2006.
Accepted on: 22 July 2006.
___________________IEEE Transactions on Learning Technologies
Submitted on: 16 December 1999.
Revised on: 02 February 2000.
Accepted on: 22 March 2000.
___________________IEEE Transactions on Learning Technologies
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Submitted on: 17 February 2012.
Revised on: 20 May 2012.
Accepted on: 15 June 2012.
___________________IEEE Transactions on Learning Technologies
http://reply.papertrans.cn/2/121/12024/12024-15.png
Submitted on: 30 November 1999.
Revised on: 01 March 2000.
Accepted on: 27 March 2000.
___________________IEEE Transactions on Learning Technologies
Submitted on: 17 May 2008.
Revised on: 09 July 2008.
Accepted on: 31 July 2008.
___________________IEEE Transactions on Learning Technologies
Submitted on: 16 June 2018.
Revised on: 19 July 2018.
Accepted on: 26 August 2018.
___________________IEEE Transactions on Learning Technologies
Submitted on: 30 December 2016.
Revised on: 28 March 2017.
Accepted on: 26 May 2017.
___________________IEEE Transactions on Learning Technologies
Submitted on: 17 March 2007.
Revised on: 08 April 2007.
Accepted on: 20 April 2007.
___________________IEEE Transactions on Learning Technologies