中文摘要：

Hai-Long Liu is currently a postgraduate student at School of Computer, Northwestern Polytechnical University, Xi＇an, China. He is a student member of China Computer Federation. His current research interest is data management technologies.E-mail：liuhailong@nwpu.edu.cn Qun Chen is currently a professor at School of Computer, Northwestern Polytechnical University, Xi＇an, China. He is a member of China Computer Federation. He received his Ph.D. degree in computer science from National University of Singapore in 2003. Between 2004 and 2006, he was a research associate in Hong Kong University of Science andTechnology. His research interests include RFID data management, XML database technologies and Web service technologies. He has published dozens of research papers in top ranked database conferences and journals. He is also a technology consultant to many mainland and HK companies.E-mail：chenbenben@nwpu.edu.cn Zhan-Huai Li is a professor at School of Computer, Northwestern Polytechnical University,Xi＇an, China. He is vice dean of the school and vice chairman of Database Technical Committee, China Computer Federation. He is a senior member of China Computer Federation. He received his Master＇s and Ph.D. degrees from Northwestern Polytechnical University in 1987 and 1996 respectively. His current research interests include RFID data management and multimedia real-time database.E-mail：lizhh@nwpu.edu.cn