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Submitted on: 06 April 2000.
Revised on: 23 May 2000.
Accepted on: 10 June 2000.
___________________Engineering Studies---ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD
Submitted on: 08 October 2018.
Revised on: 03 December 2018.
Accepted on: 27 December 2018.
___________________Engineering Studies---ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD
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