About UASL: History | In the News | Design & Architecture
The UASL Project is currently in development. Information on these pages will be updated accordingly. If you have any questions or comments please email Bob Harris boss@cast.uark.edu
Design and Architecture V 1.5
UASL Enterprise Architecture
UASL is a comprehensive, enterprise geospatial geodata system, including web-based data search and delivery, support for multiple enterprise applications and an integrated Oracle enterprise-class distributed database architecture. The system currently includes all publicly available location-based geodata for the state of Arkansas. UASL is the nation's first seamless statewide geospatial database that allowed heterogeneous access to spatial data so that users can easily locate, access, and use multiple scales of over two terabytes of raster and vector spatial data. Although more than fifteen states now have digital data warehouses, none has the versatility and relative ease of use which is possible due to the seamless nature of data representation and underlying architecture seen in UASL.
The data distribution component of UASL is an Internet-based Oracle 8i-based (soon to be 9i) spatial data warehouse, a set of Java-based services and third party products that enable data discovery, visualization, re-projection, reformatting, and download. The warehouse contains a digital collection of some 2 terabytes containing more than 425 seamless feature classes (a.k.a. themes or layers). These feature classes, statewide in extent, represent the seamless integration of more than 14,000 "traditional" map data files in vector (e.g. roads, county boundaries, flood zones, city limits, etc.), imagery (e.g. satellite imagery, digital aerial photography, etc.) and grid (e.g. National Elevation Dataset Digital Elevation Models, etc.) formats. Data have been provided by a broad range of federal, state and local agencies and (currently) are all publicly accessible - though the system design permits multiple levels of security so that different users can view different versions of the data. The attached list provides the current feature classes. In addition to a broad range of federal agencies, many state agencies have provided extensive data, particularly the Arkansas Highway and Transportation Department.
There have been more than 20,000 seamless dataset downloads from UASL in the past year representing more than 600,000 file downloads in a traditional file based system. In addition to providing a publicly accessible geospatial data, UASL has been designed to serve as an enterprise asset within the Arkansas Enterprise Architecture. As a result, the same Oracle 8i database serves multiple middle-wares from many vendors. Web mapping applications from MapInfo (MapXtreme), ESRI (ArcSDE/ArcIMS), PCI Geomatics (PCI Web Map), Intergraph (Web Map Enterprise) are operational or will be shortly. A set of different applications suites (e.g. ArcGIS 8.1, MapInfo 6, GeoMedia 4, PCI Geomatica 8.2, etc.) also connect to the same data store. In May 2002 UASL will be added to the Geography Network (www.geographynetwork.com). The RAPID project (utilizing PCI Geomatica and locally developed Java servelets) permits real-time acquisition of a variety of satellite data sources and automatic loading of GIS ready-data into UASL (www.cast.uark.edu/cast/rapid). OpenGIS Consortium (OGC) compliant web mapping services are part of the UASL architecture and an OGC Web Mapping Client has been developed that utilizes UASL and other OGC web servers (http://www.cast.uark.edu/cast/webclient/). UASL's architecture will also be utilized as part of a cooperative effort between the USGS's National Map Project and the Arkansas State Land Information Board.
Specialized applications have been built using UASL that focus on the Arkansas Department of Economic Development and the economic development community generally, including regional development districts and local communities. The Arkansas Economic Development Atlas (www.cast.uark.edu/cast/econ_dev) is an easy-to-use portal for economic development information for the state accessing UASL and is built using ArcIMS, ZOPE and other tools. The application uses UASL data to create American Economic Development Council's standardized data sets (http://www.aedc.org/dataStandards/) for 100 Arkansas communities and provides these and other geospatial data to potential development candidates over the web.
The architecture has been designed with capabilities to support distributed databases, versioning, long-transactions, and other enterprise architectural requirements - efforts are now underway to develop remote systems as part of a 9i-based clustered database. The system is fully compliant with OpenGIS Consortium (OGC) and ISO standards and with the emerging SQL 3/MM standard.
The geospatial data delivery portion of the UASL system, http://www.cast.uark.edu/cast/UASL is accessed via the web and provides a variety of methods for locating, viewing, and downloading metadata and data. For those who require only a portion of a statewide coverage or specific types of data, the system provides a variety of methods that can be used alone or collectively to restrict searches to data categories and/or to specific locations. Each data element in UASL has associated metadata to describe the inherent characteristics of each layer, or theme, of information. Metadata, or text type search filters, can be defined to restrict the number of themes to be examined for content within an area of interest. A user-defined geographic area of interest serves as a spatial filter to restrict the database search to a particular location. A filter can be defined in a number of different ways and results in an inquiry that uses quad and R-trees indexes, returning only the data layers that contain features within the area of interest. A geographic area is easily defined by entering point location and buffer zone size (including address geocoding), by entering bounding box coordinates, or selecting a preexisting polygon such as a county boundary, zip code zone, or Township/Range/Section. Alternatively, much of this information can be specified graphically by placing points or bounding boxes on an interactive map.
UASL delivers data that is clipped to the user specified area from the seamless data and can be used, without further modification, in a wide range of vendor formats as well as OGC WMT 1.0 - all of which assure a standards-compliant, platform-independent system. Data layers that are selected for download are re-projected to a selected datum (e.g. NAD27, NAD83, HARN) and projection (e.g. UTM, SPCS, LatLon). The vector data is then converted to a user-selected format (e.g. ESRI Shapefile, ESRI Coverage, ESRI Export, ESRI geodatabase, Intergraph DGN, Intergraph GeoMedia warehouse, AutoCAD DXD/DWF, MapInfo TAB or MIF/MID, geodatabase). Imagery data (e.g. aerial photography) can be delivered in a "raw" format or in the same range of projections and datums in seamless GeoTIFF formats or the users can specify (if desired) compression technique (e.g. ECW, MrSID) and amount to be dynamically applied to the data. For grid data (e.g. NED digital elevation models) users can specify format (e.g. ASCII GRID, ESRI BIL, ERDAS LAN, PCI PIX, IDRISI GRID etc.), projection and datum. Safe Software's FME is used to process the vector data and PCI Geomatics GeoGateway for grid and GeoGateway and LizardTech MrSID for image data.
Based on internet domains, major users of the data distribution system are state agencies and private sector companies followed by universities, local communities, K-12 and federal agencies.
All UASL data layers are documented in the Arkansas GeoLibrary, which is a Federal Geographic Data Committee (FGDC) metadata standards-compliant National Spatial Data Infrastructure (NSDI) Clearinghouse node. UASL metadata is developed as an integral component of the data development effort. With current FGDC support, Web Mapping Client/Servers (WMS1.0) and GML server capabilities are being added to UASL. It is hoped that future FGDC funding will allow the FY03 development and implementation of a Web Mapping Feature Server (WMS 1.11). Expanded OpenGIS integration is anticipated through CAST's participation in both OGC Web Services Initiative Thread Set 2 (OWS 1.2), aimed at developing Style Management and Sensor Web service components, and the Geospatial Information for Sustainable Development Initial Capability Pilot (GISD-ICP).
UASL was recognized as a national laureate by the Computerworld Smithsonian Innovation Program in 1999. In 2001 the State of Arkansas' GIS programs (including UASL) were ranked as ninth in the US by Digital Government Magazine.
Over the past three years, the Center for Advanced Spatial Technologies, University of Arkansas, Fayetteville, developed the UASL system under the guidance of the Arkansas State Land Information Board, the Arkansas Executive Chief Information Office and the Arkansas State Geographic Information Office. Public sector cooperators include the Arkansas Department of Information Systems, Arkansas State Highway and Transportation Department, Federal Geographic Data Committee, Arkansas Soils and Water Conservation Commission, Arkansas Department of Economic Development, US National Resource Conservation Service, US Geological Survey, City of Alma, Western Arkansas Planning and Development District, and Sebastian County. Private sector partners include ESRI, Intergraph, LizardTech, MapInfo, Nortel Networks, Oracle, Open GIS Consortium, PCI Geomatics, Safe Software, and Sun Microsystems.
UASL Design and Operational Considerations
April 12, 2002
By
Douglas Meredith, Deborah Harmon, John Wilson, Robert Harris, James Sullins
and W. Fredrick Limp
Center for Advanced Spatial Technologies
University of Arkansas, Fayetteville
