Submitted on: 05 September 2004.
Revised on: 18 October 2004.
Accepted on: 24 October 2004.
NULL
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http://reply.papertrans.cn/3/277/27700/27700-13.png
Submitted on: 26 June 2003.
Revised on: 07 August 2003.
Accepted on: 19 August 2003.
NULL
http://reply.papertrans.cn/3/277/27700/27700-15.png
Submitted on: 10 April 2013.
Revised on: 17 May 2013.
Accepted on: 08 June 2013.
NULL
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http://reply.papertrans.cn/3/277/27700/27700-18.png
Submitted on: 19 March 2010.
Revised on: 29 March 2010.
Accepted on: 08 April 2010.
NULL
http://reply.papertrans.cn/3/277/27700/27700-20.png