Transcript GML Application Schema

Community semantics and interoperability:
the ISO/TC 211 framework and the “Hollow World”
Simon Cox
CSIRO Exploration and Mining
6 September 2005
www.csiro.au
Outline
ISO framework for community application schemas
Example of process & product in geoscience
Some issues
Application schema
Premise: communication occurs within communities
Successful information transfer occurs when parties share a
common language
This also applies to transfer of technical data
How much is “common”?
 Concepts
 Models and structures
 Vocabularies
 Encodings
Application schema
Developing a community language
Two purposes:
1. Common understanding of a particular
application field.
2. Create schema for data management.
Stepwise process:
1. Survey requirements from field of
application (Universe of Discourse).
2. Identify feature types, their properties
and constraints.
3. Describe application schema in a
formal modelling language.
4. Integrate formal application schema
with other standardized schemas,
(spatial schema, quality schema, etc.)
ISO 19109 Geographic Information – Rules
for Application Schema
Application schema
Domain-specific feature types - geology
Borehole
 collar location
Conceptual classification
 shape
Multiple geometries
 collar diameter
Fault
 length
 shape
 operator
 surface trace
 logs
License
 displacement
 related area
observations
 age
 …  issuer
Ore-body
 …
 holder
 commodity
 interestedParty
 deposit type
 shape(t)
 host formation
Observation
 right(t)
 shape
 time
 …
 resource estimate
 target/location
 …
 property
 procedure +
“Natural” features
operator
Constructed artefacts
 result
 …
Artefacts of investigation
Application schema
Structure of a feature-type
Application schema
Relationships between feature types
Application schema
ISO/TC 211- Implementation
19103 – conceptual schema language
 Profile of UML
19118 – encoding rules (UMLXML)
19136 – Geography Markup Language
 WXS implementation of Features, Geometry, Temporal, CRS
Application schema
Modelling methodology
1. Get key community representatives engaged
Application schema
IUGS-CGI “Model and encoding task group”
2003 November – BGS Edinburgh
 28 people from 15 geological surveys
2004 April – GSC Ottawa
 4 people from
USGS, GSC, CSIRO
2004 December – CSIRO Perth
 11 from
USGS, AZGS, GSC, BGS,
GSJ, GSV, GSWA, GSNSW,
CSIRO
2005 August – GSC Ottawa
 8 from:
USGS, AZGS, GSC, BGS,
GSV, CSIRO
Application schema
Modelling methodology
1. Get key community representatives engaged
2. Design using UML class diagrams

use “Hollow World” UML template

includes selection of ISO, OGC and SEE Grid models

implements ISO 19103 profile of UML
i.e. compatible with GML meta-model & mapping rules
Application schema
Hollow-world in UML IDE
Application schema
Modelling methodology
1. Get key community representatives engaged
2. Design using UML class diagrams
 use “Hollow World” UML template
 includes selection of ISO, OGC and SEE Grid models
 implements ISO 19103 profile of UML
i.e. compatible with GML meta-model & mapping rules
3. Use hand-coded sample instance documents to test
model – iterate
Application schema
Serialization for transfer
<sa:Specimen gml:id="sp1"
…>
<gml:description>Specimen test instance</gml:description>
<gml:name>Specimen test 1</gml:name>
<sa:location>
…
</sa:location>
<sa:sampledOn xlink:href="http://my.big.org/station/st13"/>
<sa:sampleTime ></gml:TimeInstant …
/></sa:sampleTime >
<sa:material codeSpace=“urn:x-seegrid:lexicon:specimenType">chips</sa:material>
<sa:mass uom=“kg">0.35</sa:mass>
<sa:reportingSpecimen xlink:href="http://my.big.org/specimen/sp34"/>
<sa:processingStep>
…
</sa:processingStep>
<sa:processingStep xlink:href="http://my.big.org/pst/p98"/>
<sa:relatedObservation xlink:href="http://my.big.org/obs/m45"/>
Application schema
</sa:Specimen>
Modelling methodology
1. Get key community representatives engaged
2. Design using UML class diagrams
 use “Hollow World” UML template
 includes selection of ISO, OGC and SEE Grid models
 implements ISO 19103 profile of UML
i.e. compatible with GML meta-model & mapping rules
3. Use hand-coded sample instance documents to test
model – iterate
4. Link with utility and related packages
Application schema
GeoSciML – package dependencies
Application schema
ISO/TC 211- Standard models and components
19123 – coverage schema
 continuous data, grids
19107 – spatial schema
 geometry & topology
UML class models
19111 – coordinates & reference systems
 influenced by EPSG/POSC
19108 – temporal schema
 temporal objects and reference systems
19141 – moving-features schema
Application schema
Assembling an application schema - GeoSciML
GML
NADM
O&M/XMML
GSV
Application schema
Modelling methodology
1. Get key community representatives engaged
2. Design using UML class diagrams

use “Hollow World” UML template

includes selection of ISO, OGC and SEE Grid models

implements ISO 19103 profile of UML
i.e. compatible with GML meta-model & mapping rules
3. Use hand-coded sample instance documents to test model – iterate
4. Link with utility and related packages
5. Generate XML Schema (GML Application Schema) either

by hand following UML2GMLAS rules or

from XMI using ShapeChange application
… “Model Driven Architecture”
6. Publish model and service profiles

Feature-type catalogue

UML/XMI, XML Schema, OWL?, ISO 19126??

Registry …
Application schema
Issues: observational data
Scientific data is different …
Property values are often estimated, not assigned
 observation procedures and uncertainty
 “property-level” metadata
<LithostratigraphicUnit>
<beddingThickness basis="http://your.serious.org/observations/d1.xml">
<NumericValue>
<qualifier>mostly</qualifier>
<principalValue uom="m">0.35</principalValue>
<plusDelta uom="m">0.05</plusDelta>
<minusDelta uom="m">0.025</minusDelta>
</NumericValue>
</beddingThickness>
</LithostratigraphicUnit>
Application schema
Package of feature types for observational data
Application schema
Issues: property values
You ain’t finished yet … structure is not enough
 scales, units of measure required for numeric values
 vocabularies/lexicons required for category values
 definitions may refer to prototype or exemplar feature instances …
Application schema
Issues: registration and governance
Users must have access to language definition,
in order to use data and services
 feature-types and lexicons must be registered
 community must use an orderly governance process
ISO 19135:
Procedures for Registration of
Items of Geographic Information
Application schema
ISO/TC 211- Governance
19109 – feature model
19110 – feature cataloging
 … a community vocabulary
19126 – data dictionary registers and feature catalogue
registers
19135 – Procedures for registration of items
 governance principles
19115 – dataset metadata
19119 – service metadata
Application schema
Summary
ISO provides framework for developing application
language for geospatial communities
 methodology
 standard components
Elements:
 Concepts – feature-catalogue
 Models and structures – UML application schema
 Vocabularies – ontologies?
 Encodings – GML application schema
Application schema
More info
SEE Grid TWiki
 https://www.seegrid.csiro.au
Standards framework for geospatial information
 https://www.seegrid.csiro.au/twiki/bin/view/Infosrvices/StandardsFramework
Information models and community languages
 https://www.seegrid.csiro.au/twiki/bin/view/Infosrvices/InformationViewpoint
UML & GML
 https://www.seegrid.csiro.au/twiki/bin/view/Xmml/UmlGml
 https://www.seegrid.csiro.au/twiki/bin/view/Xmml/UmL2GMLAS
Application schema
CSIRO Exploration and Mining
Name
Simon Cox
Title
Research Scientist
Phone
+61 8 6436 8639
Email
[email protected]
Web
www.seegrid.csiro.au
Thank You
Contact CSIRO
Phone
1300 363 400
+61 3 9545 2176
Email
[email protected]
Web
www.csiro.au
www.csiro.au
Application schemas build on common components
Application schema
Open Geospatial Consortium
Primarily a vendor consortium,
Implementation specifications
 Service interfaces
 Data encodings
Interoperability projects
Application schema
From discourse to data
Application schema
OGC - Service interfaces (selection)
Web Map Service
 Fixed resolution maps (styled)
Web Feature Services
 Fine-grained data access – object-oriented
Web Coverage Service
 Access to continuous data
Catalogue Service
 Data/service discovery – metadata
Sensor Web
 live data, tasking and scheduling
 adapt for simulation services
Application schema
OGC Services
Application schema
OGC - Information standards & profiles
Geography Markup Language
Observations and Measurements
Core catalogue record
Map context
 state, data product
Styled-layer descriptor
Gazetteer profile for WFS
 GML implementation of ISO 19112
XLS for Location-based-services
Application schema
Four layer model
Application schema