Submitted on: 04 February 1999.
Revised on: 01 March 1999.
Accepted on: 05 April 1999.
___________________Advances in Electrical and Electronic Engineering
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Submitted on: 27 January 2014.
Revised on: 01 March 2014.
Accepted on: 29 April 2014.
___________________Advances in Electrical and Electronic Engineering
Submitted on: 22 July 2001.
Revised on: 16 November 2001.
Accepted on: 02 December 2001.
___________________Advances in Electrical and Electronic Engineering
Submitted on: 25 May 2014.
Revised on: 06 August 2014.
Accepted on: 21 August 2014.
___________________Advances in Electrical and Electronic Engineering
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Submitted on: 07 February 2003.
Revised on: 29 April 2003.
Accepted on: 09 June 2003.
___________________Advances in Electrical and Electronic Engineering
Submitted on: 29 November 2004.
Revised on: 14 January 2005.
Accepted on: 13 March 2005.
___________________Advances in Electrical and Electronic Engineering
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