9870724 Chase, Jeffrey S. Agarwal, Pankaj K. Duke University Experimental Software Systems: Geographic Information Systems on High-Speed Clusters: A Vertically Integrated Approach Geographic Information Systems (GIS) are important management and analysis tools in science, and government. Practical interest in GIS has spurred fundamental research in several areas of computer science. However, this research has focused mainly on abstract problems, and technology transfer to GIS practitioners has been slow. This project seeks to develop an improved foundation for dealing with massive spatial data through a collaboration of researchers in computer algorithms, software systems, and environmental sciences. The research deals with GIS problems at all levels of abstraction-from applications to algorithms, systems, and tools. The algorithmic research builds on recent advances in geometric algorithms and I/O-efficient algorithms for problems that arise in GIS. The systems research seeks to develop and evaluate system support for I/O-intensive applications on networked clusters, incorporating experimental research in storage systems, memory management, and networking. The common focal point for all project members is a toolkit that supports practical implementations of GIS algorithms and applications. The expected outputs of the research are: (1) new algorithms for dealing with massive spatial data sets, (2) whole-system implementations of GIS algorithms on high-speed clusters, and (3) transfer of these computational advances into the practice of GIS in the environmental sciences.