Submitted on: 28 April 2008.
Revised on: 21 May 2008.
Accepted on: 18 June 2008.
Sustainable Computing-Informatics & Systems
Submitted on: 19 November 2009.
Revised on: 14 December 2009.
Accepted on: 01 January 2010.
Sustainable Computing-Informatics & Systems
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