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GEON papers to be featured in moderated session (August 10, 2004, 8:30 a.m.) at 24th Annual ESRI International User Conference ESRI UC Paper number 1692 Title GEON: Standards-based Secure Invocation of ArcWeb Services Authors Memon, Ashraf, Chaitanya Baru, Ilya Zaslavsky, Steve Mock, Amit Behere (San Diego Supercomputer Center, University of California, San Diego) Within the Geosciences Network (GEON) project, we implemented a secure mechanism of data interchange across distributed spatial databases and services, a common requirement in many geographic applications. The paper explores OGSI-based grid services that implement Grid Security Invocations (GSI), and describes an application of this model to secure invocation of ArcWeb services. Currently, ArcWeb services use single sign-on security model, in which, on initial authentication, the user is assigned a time-limited numeric token that is passed along with the request message and used to unlock an ArcWeb service. We implemented a GSI authentication wrapper on top of ESRI's token-based authentication mechanism. To invoke an ArcWeb service on the secure grid, the user first requests a time-limited proxy certificate by providing a user name and passphrase to a certificate authority. This certificate, which is transmitted inside SOAP headers of all service requests, is verified each time before a service is invoked. ESRI UC Paper number 1796 Title GEON: Ontology-Enabled Map Integration Authors Lin, Kai, Bertram Ludaescher (San Diego Supercomputer Center, University of California, San Diego) In the GEON project we are developing an interoperability system on top of ArcIMS for registering spatial data sets to ontologies and subsequently querying registered data sets through the ontologies for map rendering. The system consists an ontology repository, a data set registration procedure, and a query rewriting system. User-defined ontologies are imported as OWL files and saved in the ontology repository. Structural and semantic heterogeneities of data sources are resolved using information from the data set registration procedure and ontology information. Those are used when rewriting user queries (e.g., a geologic age or rock type will expand to their corresponding "subconcepts" in the rewritten query). Multiple ontologies are supported in the system by allowing users to define a morphism between two ontologies which equates some concepts in the source ontology to some concepts in the target ontology. Users are able to switch between ontologies for which an ontology morphism exists. ESRI UC Paper number 1791 Title GEON: Assembling Maps on Demand from Heterogeneous Grid Sources Authors Zaslavsky, Ilya, Ashraf Memon (San Diego Supercomputer Center, University of California, San Diego) Integrating spatial information from multiple grid-enabled sources of geologic data is an important component of the NSF-funded Geosciences Network (GEON) project. The spatial integration is orchestrated by GeoGEMS (Grid-Enabled Mediation Services), a collection of grid services that support spatial data mediation, ontology and schema conflict resolution, and composite map assembly. Geologic data are served by distributed ArcIMS and WMS servers, each wrapped in WSDL/SOAP wrappers. Capabilities of each source are registered at the mediator, so that the latter can plan and orchestrate query execution. To produce a composite result, query results retrieved from individual sources are either merged at the mediator or overlapped at the client. A comprehensive GEON map assembly service represents a temporary mediator-level ArcIMS service that is created on demand to merge individual raster and vector fragments from distributed servers into a composite map, and generate answers to follow-up requests without requerying the sources. ESRI UC Paper number 1790 Title GEON: The GEON Grid Software Architecture Author Baru, Chaitan (San Diego Supercomputer Center, University of California, San Diego) The Geosciences Network (GEON) is a multi-university project funded by the National Science Foundation to develop cyberinfrastructure to enable sharing of data sets and services in a distributed environment, for the Earth Sciences. The GEON Grid is a distributed network of _GEON nodes_, each of which runs a GEON _software stack_ that includes Web and Grid services to enable users to register data sets; register services; issue queries across multiple information sources, using spatiotemporal search conditions and ontologies; download data into personal spaces; invoke analysis services; and visualize output of queries and/or analysis. The architecture includes data mediation services, workflow services, and a portal. Much of the data is geospatial and spatiotemporal in nature and providing appropriate search interfaces and efficient mapping interfaces for such data is an important requirement. The GEON Grid software stack will include ArcIMS as one of its components to provide GIS and mapping functionality. Title GEON: ArcIMS Online Mapping to Facilitate Integration of Geoscience Data Author Arrowsmith1, J.R., G. Randy Keller2, Jeff Conner1, J. Yoburn1, L. Prashad1, C. Eisinger1, W.L. Stefanov1, M.J. Fouch1 (1=Department of Geological Sciences, Arizona State University, Tempe, AZ 85287, [email protected]; 2=Department of Geological Sciences, University of Texas El Paso, El Paso, TX) The Colorado Plateau-Basin and Range Transition Zone of Arizona and New Mexico comprises an important geologic setting in which the study of continental crustal evolution and deformation is particularly intensive. In addition, it is a region of rapid population growth where balancing resource use, resource preservation, and sustainable land use is increasingly important. To inform such efforts, we have gathered geological data (e.g., geologic outcrops at various scales, active fault maps), digital topography (USGS NED and SRTM 30 m), ASTER satellite imagery, and geophysical data (e.g., gravity, heat flow, seismicity, seismic anisotropy, magnetics, receiver functions, seismic tomography), and integrated them using ArcIMS. We have also developed a Java Servlet-driven IDL-cored image processing system to produce user-specified (from imagery footprints in ArcIMS) ASTER band combinations in GeoTiff format. This data system is an initial step in the development of a seamless data and scientific analysis portal as part of the GEON project.