From the Fall 2006 issue of Threads
Hao He joined the Department of Computer Science in Fall 2001, having completed his undergraduate and MS degrees at China’s premier Tsinghua University. He is pursuing his PhD in the area of database systems under the supervision of Jun Yang.
He is broadly interested in data management research, focusing on query processing and indexing techniques on graph-structured data. During the past several years, He has aimed to develop query processing algorithms and indexes for some specific graph-structured data and queries. During his second year, he began to work with Professor Yang on indexing and labeling XML data, which is generally represented as tree-structured. Then he worked on supporting reachability queries on general graphs.
Recently, he began working on an indexing and query processing scheme for ranked keyword search on directed graphs. Keyword search on a node-labeled graph finds a set of answers, each of which is a substructure of the graph containing all query keywords. These answers can be ranked according to how strong the connections of nodes are in each answer. In this project, He proposed a new search strategy with provable performance bounds, while additionally exploiting a novel index for pruning and accelerating the search. The new scheme turns out to offer orders of magnitude performance improvement over existing approaches.
He has a strong publication record, with numerous papers in top database conferences. His work on dynamic indexing schemes for XML data is outstanding, as evidenced by He being a recipient of an IBM PhD fellowship for the 2006-2007 academic year.
He spent the summers of 2004, 2005 and 2006 working with Philip Yu’s group at the IBM T.J. Watson Research Center in Hawthorne, NY. This ongoing collaboration gives testimony to He’s creativity, knowledge, and diligence in his research work.