Submitted on: 10 December 2003.
Revised on: 19 February 2004.
Accepted on: 03 March 2004.
___________________IEEE TRANSACTIONS ON MEDICAL IMAGING
Submitted on: 25 November 1998.
Revised on: 25 December 1998.
Accepted on: 18 January 1999.
___________________IEEE TRANSACTIONS ON MEDICAL IMAGING
http://reply.papertrans.cn/2/121/12029/12029-33.png
http://reply.papertrans.cn/2/121/12029/12029-34.png
http://reply.papertrans.cn/2/121/12029/12029-35.png
http://reply.papertrans.cn/2/121/12029/12029-36.png