中文摘要：

Siyuan Liu is a research scientist at Carnegie Mellon University. He re- ceived his first PhD degree from De- partment of Computer Science and En- gineering at Hong Kong University of Science and Technology, China in 2011, and the second PhD degree from University of Chinese Academy of Sci-ences in 2004. His research interests include big mobile data man- agement and heterogeneous social networks mining. Shuhui Wang received the PhD degree from the Institute of Computing Tech- nology, Chinese Academy of Sciences, Beijing, China in 2012. He is currently an assistant professor with the Insti- tute of Computing Technology, Chi- nese Academy of Sciences, Beijing. His research interests include large- scale Web data mining, visual semanticanalysis and machine learning.E-mail： sy.liu@siat.ac.cn Ce Liu is a PhD student at telecom- munications and networking in School of Information Sciences of University of Pittsburgh. Her research interests in- clude vehicular networking and wire- less networks. Ramayya Krishnan is the dean of Heinz College. He holds the John Heinz III Deanship and is the W. W. Cooper and Ruth F. Cooper Professor of Manage- ment Science and Information Systems at Carnegie Mellon University. He has a PhD degree in Management Science and Information Systems from the Uni- versity of Texas at Austin.