In recent work, the results on visual data exploration from the NEXT! project, which is joint work with Prof. Livny, are being applied to data integration, and querying over the Web.
My second area of interest is content-based querying of complex data such as sequences and image sets. The SEQ system deals with queries over sequence data, and focuses on DBMS design and optimization issues related to sequence data. It is a part of the NEXT! project, and is joint work with Prof. Livny. An important aspect of this work is its use for identifying trends in the data, or in general, identifying useful patterns of information. In the PIQ project, the goal is to support content-based retrieval from large sets of images. Our focus is on developing and implementing an expressive data definition language that can be used to customize a general image database system to take advantage of specialized information about a given collection of images that is to be indexed and queried.
My interest in querying and analysis of data covers data exploration and mining. We have developed a powerful clustering algorithm called BIRCH for large datasets and a visual data exploration tool called DEVise as part of the NEXT! project. A long-standing research interest is the extension of relational database query languages with logic programming features such as structured terms and recursion, and the use of arithmetic constraints to specify data and queries more compactly and efficiently. An ongoing project involves the continued development and use of the CORAL deductive system. The evaluation is based upon bottom-up fixpoint evaluation techniques, and several optimizations are applied to make it efficient across a broad range of programs.
S. Sudarshan, Ph.D. August 1992, Run-Time Optimizations in Bottom-Up Evaluation of Logic Programs, First employment: AT&T Bell Labs, Murray Hill (sudarsha@research.att.com).
D. Srivastava, Ph.D. August 1993, Deductive and Object-Oriented Languages, First employment: AT&T Bell Labs, Murray Hill (divesh@research.att.com).
S. Dar, Ph.D. August 1993, Design and Evaluation of Transitive Closure Algorithms, First employment: AT&T Bell Labs, Murray Hill (dar@research.att.com).
P. Seshadri, Ph.D. August 1996, Sequence Data Management First employment: Computer Sciences Department, Cornell University (praveen@cs.cornell.edu).