1990.07—1997.09 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxxx
( 1994.09—1997.07xxxxxxxxxxxx)
1997.09—2000.04 xxxxxxxxxxxxxxxxxxxxxxxx
2000.04—2004.06 xxxxxxxxxxxxxxxxxxxxxxxx
(1999.09—2002.05xxxxxxxxxxxxxxxxx)
2005.04—2008.03 xxxxxxxxxxxxxxxxxxxxxxxx
2008.03—2010.03 xxxxxxxxxxxxxxxxxxx
2010.03—2011.06 xxxxxxxxxxxxxxxxxxxxxxxxxx
2011.06—至今 xxxxxxxxxxxxxxxxxxxxxx