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GeoSpatial Systems – Metaknowledge Mashup. Dan Rickman GeoSpatial SG. Agenda. What are GIS What is GeoSpatial Data Data management issues Neo-Geography Standards Current and future developments. What are GeoSpatial Systems?.
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GeoSpatial Systems – Metaknowledge Mashup Dan Rickman GeoSpatial SG
Agenda • What are GIS • What is GeoSpatial Data • Data management issues • Neo-Geography • Standards • Current and future developments
What are GeoSpatial Systems? • Known as Geographic Information Systems, Spatial Information Systems • Enables capture, modelling, storage, retrieval, sharing, manipulation and analysis of geographically referenced data • Not CAD! Database is at the heart – as is “attribute” data • Model developing – perhaps GeoSpatial data better seen as “attribute” of alphanumeric business information • Presentation does not have to be map-based in all cases • Key element is spatial indexing – uses different techniques to alphanumeric indexing
What is Geospatial Information? - 1 • Spatial data which relates to the surface of the Earth • Geodetic reference system as base e.g. WGS84 used for Global Positioning System (Earth as an ellipsoid), Latitude and Longitude (Earth as a sphere) • Ordnance Survey (GB) define National Grid – projection onto flat surface – NB: OS(NI) use Irish grid • Spatial relationships – defined around concept of neighbourhood – relates to two “laws” of geography: • Most things influence most other things in some way • Nearby things are usually more similar than things which are far apart
What is Geospatial Information? - 2 • Unstructured – spaghetti data • Topology – information structured as networks, polygons • GeoSpatial information requires metadata – e.g. minimal information such as map projection used • GeoSpatial information may also temporal modelling – e.g. farm subsidies vary as utilisation and legislation change • Field-based model versus object-based model of space, e.g. rainfall versus buildings on which rain falls • GeoSpatial information requires ontology • What is the “real world”, how classified • Relates to semantics
Where used? Examples • Central government – DEFRA, ODPM, Land Registry, ONS • Local government – planning, highways authorities • Utilities – physical and logical network • Insurance – flood plains • Health – epidemiology • Travel, multi-modal route planning • More widespread use – addresses, postcode based data against regional boundaries, infrastructure (“geographies” used to divide country, catchment area) • Fiat boundaries verus “bona fide” boundaries – what is “real world” how do we structure it?
Structured geo-databaseParadigm shift? Relational Database (Attribute data) Spatial Data (proprietary format) Real Time/Engineering Systems CRM ERP • Spatially extended RDBMS • Complex data types for spatial data • Computational geometry • Spatial indexing • DDL and DML extensions
Networks and Topology • Routing • Connectivity • Explicit spatial relationships • Can be complex - one way, • - restricted turn • - average speed • …
Terrain and 3D • Line of sight • Radio Propagation • Flood • Water Pressure
Temporal Time as a dimension or measure How things change over time
Geospatial data modelling • Field-based model versus object-based model • Geographic Information Systems are object-based in practice • Most common field based information, e.g. Digital Elevation Model (line of sight applications), attached to objects • Objects rely on field-based model, i.e. spatial co-ordinates • Initiatives such as Digital National Framework encourage organisations to structure data on references to objects, not re-capture and duplicate data • GeoSpatial equivalent of “referential integrity” • Nevertheless duplication, lack of (referential) integrity is common place and hard to eradicate
Digital National Framework • Capture information once and use many times • Benefits: • avoid cost of duplicate data capture • benefit through 3rd party data maintenance (i.e. avoid cost of maintaining one's own data) • benefit of improved data management especially where COU is used to identify area of change (which can then be used to focus and improve maintenance of non-spatial business object data, as appropriate) • Capture at the highest resolution possible • Benefit: • avoid re-capture later on • improve potential for data interoperability • Publish lower resolutions from this data - if required • avoids data recapture • Use existing proven standards • provides framework, avoids costs of "re-inventing the wheel" NB: sort of benefit one would expect from a strategy!
In search of the BLPU • Basic Land and Property Unit • “Holy grail” of industry – no Da Vinci code produced yet! • Example of Ordnance Survey Master Map (OSMM): • "St Mary's football stadium, Southampton" is one object • Typical detached house and its plot of land, likewise • Complex entities such as "Southampton railway station" are defined in terms multiple objects: one for the main building, several for the platforms, one more for pedestrian bridge over the tracks. (NB: See Wikipedia article on TOID) • Defining the candidate BLPU, their lifecycles and their attribute data and verifying that these are meaningful/practicable from the wide variety of business processes which apply to the BLPU and the aggregate entities which are created from them • Dependencies so that data sets are based on the BLPU wherever possible limited by business use, e.g. field use change quite different from a tenant/owner perspective
database records digital records geographic information paper records digital mapping paper mapping 1990 1970 Evolution of geographic information 2010 1950
Raster map data • Scanned ortho-rectified map or map-based data – metadata is co-ordinates, projection, extent • For example Google Maps/Google Earth, Microsoft Virtual Earth • Traditionally stored outside the database as external files, analogous to vector data storage, e.g. Oracle 10g GeoRaster • Data stored as BLOBs, metadata required regarding number of bytes per pixel, compression algorithms and so on • Benefits limited as “intelligence” in map requires interpretation • Still limited progress on map-based pattern recognition – there are semi-automated solutions from companies such as Laser-Scan
Benefits of integration • Geo-spatial data mining • Spatial links • Shipman example • Visualisation • Provide new ways of linking data • Avoid capturing data e.g. DNF • Maintenance of data • Lower costs of integration and delivery at front-end • Back-end integration still an issue – data • Reduce endless data cleaning – as part of information management strategy • Reduce data maintenance costs • Improve data in business – does this matter?
Geospatial - Drivers • Awareness • Current use of data • Front end integration – Mashups • Back end – Database • Data providers • Ordnance Survey • Developing middle/large scale market • Open source data • Free our data
EDRM • Electronic document and records management • Increase usage in local/central government due to Freedom of Information act • Contain potentially significant geospatial data • Most common example is address • Requires capture of appropriate metadata or appropriate pattern recognition to identify addresses • Requires gazetteers to provide reference to spatial co-ordinates • NB: most familiar gazetteer – list of streets in AtoZ maps
Costs • Hardware – no special hardware required • Network – bandwidth generally adequate • Software – Increasingly delivered through “thin” clients • SOA – promise of mashups (WMS/WFS, Google, Yahoo, Microsoft), GeoRSS • Development skills – limited specialist skills required • Data • Still expensive • Complex • Requires re-engineering/data management • “Boring” issue – drivers often hidden in BAU
Standards • GeoSpatial widely used – in database technology, web-based systems and developing IS architecture. • Organisations already exist -BCS must be relevant • Open GeoSpatial Consortium - http://www.opengeospatial.org/ • ISO TC211 (GI/Geomatics) - http://www.isotc211.org/ • BSI Committee for GI (http://www.gistandards.org.uk/) • Association for Geographic Information (http://www.agi.org.uk) • A topic for parliamentarians (EU e.g. INSPIRE http://inspire.jrc.it/ & Westminster e.g. GI Panel http://www.gipanel.org.uk/gipanel/ Already an issue for business – significant investment • Needs to be a credible BCS specialist group • Provide voice for BCS in GeoSpatial issues • Public policy - Free our data?
Benefits for BCS Embracing part of cultural change within IS/IT/IM Microsoft, Google and Oracle significant investment and developments Prominence in “Web 2.0” sites, e.g. www.platial.com (“Collaborative atlas”) Enabling technologies/architecture such as SOA Seen as being relevant BCS recovering lost ground GIS SG previously existed No vendor tie in – no conflict of interest BCS recruitment mechanism for potential BCS members GSG: WHY
GSG: WHY • How we address GeoSpatial issues? • Vendor, academic, end user/ business experience • Survey and consensus of Group Members • How do we convey this message ? • Meetings minimum once a quarter, but ideally every 6 weeks. • A positive effort to hold meetings in the nations & regions. • Contribution to discussions, events (representation). • Web site communication • Email bulletins • Press
Summary • Geospatial now becoming mainstream • Significant developments in market, e.g. Pitney Bowes purchase of MapInfo, increasing demand for linking BI with GIS • Neo-Geography and wider awareness drive use of geospatial data • However data availability and quality are key issues, implications of this not always well understood • Metadata and catalogue standards exist not always integrated with wider standards and not always well implemented or implemented at all …