Public Reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comment regarding this burden estimates or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for information Operations and Reports, 1215 Work for this grant enabled the advancement of the state of research for areas of fuzzy spatial data modeling, uncertainty and conflation. Specific published work supported by this grant included a range of topics, including: fuzzy spatial relationship refinements, spatial query interfaces, uncertainty in distributed spatial information systems, spatial relationship querying, distributed spatial object-based systems, spatial indexing, distributed conflation model and issues, and an integrated image change detection/conflation algorithm. Special journal issues co-edited by the grant recipient on "Spatial Data Management," "Uncertainty in Geographic Information Systems and Spatial Data" and "Distributed Object-Oriented Systems" resulted in newly published works from some of the foremost researchers in the area, including Michael Goodchild, Peter Fisher, Hans Guesgen, Douglas Schmidt and others.All publications listed are included in this report package, and the reader is referred to the actual publications for details of the topics listed above.
IntroductionThis grant was originally issued for the investigation of state-of-the-art technology component-ware for distributed databases utilizing CORBA, as well as the development of a fuzzy spatial data model to provide a way of handling imprecision and uncertainty in spatial data. Specifically, the grant work was to augment ongoing development of NRL's Geospatial Information Database (GIDB) in the realm of Object Request Brokers (ORBs) and the GemStone Object-Oriented Database Management System (OODBMS).Soon after the work was initiated, however, NRL began to investigate alternate implementation architectures for the GIDB relative to its future stability and viability. Major re-design decisions were made, including: (1) a move from the Smalltalk programming language to Java, (2) replacement of GemStone OODBMS with Ozone OODBMS (Java-based), and (3) replacement of CORBA-based architecture with Java Remote Method Invocation (RMI)/applet technology. These decisions have since proven to be invaluable to the development and marketability of the GIDB; however, because this new direction made much of the proposed grant work in CORBA and related implementation issues unnecessary, and in consultation with the NRL principal scientist, the concentration of work was redirected to the areas of fuzzy spatial data modeling and conflation.After the original three years were completed, a no-cost extension was requested. This extension funded a Ph.D. scientific co...