1. & <GML/>
Galdos: Geospatial SOA Products and Solutions Provider, Systems Integrator
Ron Lake – original author of GML
WFS, WMS, and WRS products
Clients include NATO, UK MOD, Oak Ridge National Labs, Shell, FAA/
September-19-18

2. GML | business drivers
“…about 80 percent of all government information has a geospatial data component…In 1993…[an] estimated that $4.1 billion was spent annually, at the federal level, on collection and management of geographically referenced data…state and local governments are estimated to spend twice that of the federal government...”
“…about 50 percent of the federal government’s geospatial data investment is redundant.”
“…up to 80 percent of GIS costs are related to the collection and management of geospatial data.”
SOURCE: United States General Accounting Office Geographic Information Systems: Challenges to Effective Data Sharing
September-19-18

3. GML | business drivers INSPIRE
“…widespread access to and use of spatial information is still a problem in Europe. The main problems relate to data gaps, missing documentation, incompatible spatial data sets and services due e.g. to varying standards, and barriers to the sharing and reuse of spatial data.”
Directive Of The European Parliament, INSPIRE 2004
September-19-18

4. GML | value proposition
Increased utility, lower costs
Ability to leverage IT investments in unforeseen ways
Avoidance of further generations of closed, dead end solutions
savings to investment ratio of 119%
projects that adopted and implemented geospatial interoperability standards saved 26.2% compared to the projects that relied upon a proprietary standard
SOURCE: Booz, Allen, Hamilton. April Geospatial Interoperability Return on Investment Study. NASA Geospatial Interoperability Office.
September-19-18

5. <GML/> GML | technology
Open XML encoding of a standard geospatial model
ISO 19100
<GML/>
Xerces
JAXP
.NET
Saxon
Geography Markup Language is an XML grammar written in XML Schema for the description of application schemas as well as the transport and storage of geographic information.
W3C
xml
xsd
xlink
September-19-18

6. Standard logical and encoding models
GML | technology
Standard logical and encoding models
ISO/TS – Conceptual Schema Language (units of measure, basic types),
ISO – Spatial schema (geometry and topology objects),
ISO – Temporal schema (temporal geometry and topology objects, temporal reference systems),
ISO – Rules for application schemas (features),
ISO – Spatial referencing by coordinates (coordinate reference systems),
ISO – Schema for coverage geometry and functions
September-19-18

7. GML | technology Implements ISO 19100 series
ISO/TS – Conceptual Schema Language (units of measure, basic types),
ISO – Spatial schema (geometry and topology objects),
ISO – Temporal schema (temporal geometry and topology objects, temporal reference systems),
ISO – Rules for application schemas (features),
ISO – Spatial referencing by coordinates (coordinate reference systems),
ISO – Schema for coverage geometry and functions
Dynamic features: feature-level and attribute-level time stamping
September-19-18

8. GML | technology GML is XML
Open standard for representing and processing data.
Provides a way to mark up text content that adds information about its purpose.
<gml:coordinates> ,
</gml:coordinates>
Separates content and style
The alternative to using XML is to define your own proprietary data syntax, and then build your own proprietary tools to support that proprietary syntax...
Without XML there would be no Web 2.0; without GML there would be no geospatial web services
Ironically, it’s still text data – but structured and semantic
September-19-18

9. GML | technology Schema framework
Instances can be a file, parts of a file or message, database object, etc.
September-19-18

10. Universal geospatial data transport
GML | benefits
Universal geospatial data transport
GML
GML
GML
WFS
(ESRI)
WFS
(Oracle)
WFS
(PostGIS)
September-19-18

11. Information communities
GML | benefits
Information communities
Road network
Environment
Emergency
Response
Interoperability
GMLJP2
September-19-18

12. Expressive and explicit
GML | benefits
Expressive and explicit
September-19-18

13. Feature relationships
GML | benefits
Feature relationships
As in the real world, features are objects that can relate to other objects
Properties are used to explicitly model the relationship semantics
Properties can be included within a data message, or reference the target only
September-19-18

14. Real-time data integration
GML | benefits
Real-time data integration
Shared GML vocabularies increases probability of both formalized and ad hoc data integration
Data from different GML vocabularies can still be integrated through XSLT transformation and/or geospatial web services
Data is locally maintained, for specific business uses, yet can be shared and used by additional users for different purposes
AIXM
DAFIF
September-19-18

15. Enables geospatial web services
GML | benefits
Enables geospatial web services
A web service is a software interface that describes a collection of operations that can be accessed over the network through standardized XML messaging.
OGC services include Web Map Server (WMS), Web Feature Server, and Web Registry Server (WRS)
Of course, as GML is XML, it can be used interchangeably.
Communication between software applications!
September-19-18

16. Mission: timely, consistent, high quality aeronautical information
AIXM | GML
Mission: timely, consistent, high quality aeronautical information
Objectives:
A common language for expressing aeronautical information for human and computer interpretation;
Cost savings through software reuse and data model reuse;
Increased safety through improved data integrity and timeliness;
Cost reduction through improvements in data quality checking and integration.
September-19-18

17. AIXM-GML | schema framework
September-19-18

18. AIXM-GML | AIXM Profile
<AIXM-GML Profile/>
Profile includes:
Only those GML components required for AIXM and its extensions
Strict subset of GML
Unused optional properties removed; can also be made mandatory only
NO AIXM additions – illegal
Reduces schema size and complexity
Reduces handling and/or processing requirements for AIXM tools
A profile of GML is a logical restriction of a subset of GML.
A profile shall not change the name, definition, or data type of mandatory GML elements or attributes.
The relevant schema or schemas that define a profile shall use in the core ‘gml’ namespace
An application schema may extend and use types from the profile, but shall do so in its own namespace, and not use
The functional test of these rules is:
Any instance document for an application schema using a GML profile will be valid against the same
application schema if the GML profile is replaced by the complete GML schema. Further, the interpretation of
that document would be the same regardless of which of the two schemas were used.
Introduction | Business | Technology | Interactions | Future
September-19-18

19. AIXM-GML | feature identification
Implicit and explicit
Natural key: identification by property state
Explicit identifiers
<Runway gml:id="local-ID">
<gml:identifier>global-ID</gml:identifier>
...
</Runway>
September-19-18

20. Normative implicit definition Informative explicit encoding
AIXM-GML | geometry
Normative implicit definition
Informative explicit encoding
September-19-18

21. Standard geometry encoding
AIXM-GML | geometry
Standard geometry encoding
<aixm:extent>
<gml:Polygon srsName="EPSG:4326">
<gml:exterior>
<gml:LinearRing>
<gml:coordinates>...</gml:coordinates>
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
</aixm:extent>
September-19-18

22. AIXM-GML | feature lifetime
Event-driven model: feature history
certain time: version
September-19-18

23. AIXM-GML | feature lifetime
September-19-18

24. AIXM-GML | extensibility
Framework for local extensions
September-19-18

25. Work with AIXM design team to resolve any non-compliance issues
AIXM-GML | future work
Audit draft AIXM GML schemas for compliance with GML v3.1.1 specification
Work with AIXM design team to resolve any non-compliance issues
Migrate AIXM schemas to GML v3.2
Refine AIXM GML Profile
Work with AIXM design team to develop GML change proposals
CRs include:
Geodetic coordinates (CRS?)
Topology for Airspace containing geographical borders
2.5 D geometry
Arrays of referenced features
Here to:
Meet user community
Better understand AIXM requirements
Participate in design discussions
September-19-18

26. AIXM-GML | future work GML v3.2 Changes from v3.1.1
Official ISO standard
Improve consistency and usability
UML to/from GML rules according to ISO 19109
Changes from v3.1.1
New version-qualified namespace:
Even more explicit encoding
Increased emphasis on profiles
September-19-18

27. AIXM-GML | knowledge and tools
2007: From Mashups to Infrastructure
Bringing together of geospatial customers, managers, and developers
Vancouver July 07
. Sponsors: Google, ESRI, Lizardtech, CGDI
. Participants: Google, MS, ESRI, Government civilian and military agencies
. Workshops, Demos, Presentations
September-19-18