中文摘要：

Gang Wu received his Ph.D. degree from Tsinghua University in 2008. He is currently an assistant professor of Southeast University, China. His current research interests include semantic Web, XML, parallel DB, and object-oriented DB.E-mail： wu@seu.edu.cn; Juan-Zi Li is a professor at the Department of Computer Science and Technology in Tsinghua University. Her research interests is semantic Web and semantic Web ser- vices, text mining and knowledge disw covery. She is a member of China Computer Federation （CCF） and Association for Computing Machinery （ACM）.E-mail： ljz@keg.cs.tsinghua.edu.cn Jian-Qiang Hu received his Ph.D. degree in computer software and theory from the National University of Defense Technology, China, in 2005, and his M.Sc. and B.Sc. degrees in computational mathematics from Fuzhou University and Zhejiang Normal University, China, in 1998 and 1995, respectively. He is currently a post-doc research fellow in Knowledge Engineering Group at the Department of Computer Science and Technology, Tsinghua University, China. His current research interests include distributed systems integration, service composition, semantic-based requirements engineering. E-mail： jianqianghu@keg.cs.tsinghua.edu.cn Ke-Hong Wang is a professor at the Department of Computer Science and Technology in Tsinghua University. His research interests include XML based information processing and component based software technology. He is a member of CCF.E-mail：wkh @keg.cs.tsinghua.edu.cn