Submitted on: 24 September 2011.
Revised on: 03 December 2011.
Accepted on: 22 December 2011.
___________________International Journal of Continuing Engineering Education and Life-Long Learning
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Submitted on: 09 April 2013.
Revised on: 08 May 2013.
Accepted on: 02 June 2013.
___________________International Journal of Continuing Engineering Education and Life-Long Learning
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Submitted on: 16 September 2005.
Revised on: 08 January 2006.
Accepted on: 09 February 2006.
___________________International Journal of Continuing Engineering Education and Life-Long Learning