The group's research concerns a range of topics that relate to indexing and query and update processing for primarily spatio-temporal data, including moving-object indexing, spatial keyword query processing, location privacy, spatial web ranking, indoor query processing and indexing, and spatio-temporal infrastructure for mobile services and cloud computing. In addition, the group's research concerns high-dimensional and multimedia data, including retrieval,mining, clustering, and ranking using novel indexing and subspace-based techniques.