This paper describes a metadata interchange approach for semi-automated integration of heterogeneous distributed databases. Our system prototype uses distributed metadata to generate a GUI tool for a meta-user (who does the metadata integration) to describe mappings between master and local databases by assigning index numbers and specifying conversion function names; the system uses Quilt as its XML query language. A DDXMI (for Distributed Database XML Metadata Interface) file is generated based on the mappings, and is used to translate queries over the virtual master database into sub-queries to local databases. An experiment testing feasibility is reported in which 3 different bibliography databases are integrated.

of the Thesis Presented in Partial Fulfillment of the Requirements for the Degree of Master of Science (in Spatial Information Science and Engineering) August, 2000 This thesis addresses image-based change detection. Motivation was provided by the lack of algorithms that incorporate in their solution diverse types of pre-existing and complementary information and have the ability to interact with a spatiotemporal environment.

Current geographic information systems tend to follow an inherently static approach to geospatial information management. Small amounts of information are typically synthesized into map-like application-specific data snapshots. This static approach leaves large amounts of information unused and offers limited communication capabilities. Accordingly, it is unsuitable for today's applications, where geospatial information becomes increasingly dynamic and spatiotemporal in nature. In this paper we present a framework for the integration of digital images and complementary GIS datasets in a model which provides explicit information about spatiotemporal change. We propose the SpatioTemporal Gazetteer as a model that makes more effective use of multiple information resources than the traditional map model, and in particular incorporates components to track changes to objects over time. We present the general components of the model and discuss information flow in such a system. We also prese...