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 classifiedRelates 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)
SpatialData
(proprietary format)
ERP
CRM
Real
Tim
e/Engineering
System
s
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
GIS
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 timesBenefits:
– 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 possibleBenefit:
– 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 objectTypical detached house and its plot of land, likewiseComplex 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
Evolution of geographic information
1950 2010
paperrecords
digital
records
databaserecords
paper mapping
digital mapping
geographicinformation
1970 1990
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
VisualisationProvide new ways of linking data
– Avoid capturing data e.g. DNF– Maintenance of data
Lower costs of integration and delivery at front-endBack-end integration still an issue – dataReduce endless data cleaning – as part of information management strategyReduce data maintenance costsImprove 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
DfES Web Mashup
www.schoolmap.org.uk
Costs
Hardware – no special hardware requiredNetwork – bandwidth generally adequateSoftware – Increasingly delivered through “thin” clientsSOA – promise of mashups (WMS/WFS, Google, Yahoo, Microsoft), GeoRSSDevelopment skills – limited specialist skills requiredData
– 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 investmentNeeds to be a credible BCS specialist groupProvide voice for BCS in GeoSpatial issuesPublic policy - Free our data?
Web 2.0 – interactive integrated information
GSG: WHY
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
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 …