Public Access and Spatial Metadata Values: Semantic Network Services Response to EU Directives

Maria Rüther Federal Environment Agency, maria.ruether@uba.de

Thomas BandholtzinnoQ Deutschland GmbH, thomas.bandholtz@innoq.com

Semantic Network Servicewww.semantic-network.de

4th Ecoterm Group MeetingVienna, Austria, 17-18 April 2007

The role of environmental terminologies in semantic data integration

Track: WHAT ARE THE USE CASES?

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2 European Directives

• “Public Access” (2003)

• “Inspire” (2007)

http://inspire.jrc.it/

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Public Access & Environmental Terminology

biology

geology

chemistry

economics

politics

…

buzzwords

partial knowledge

mediasciences

learning

personal

public ?community

environmental informa

tion

environmental informa

tion

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Full Text Search Support

Finding the right search terms …

• terminology mediation service– getSimilarTerms()

• lookup and navigation services– findTopics()

– getPSI()

– getHierarchy()

• terms extraction services– autoClassify()

this is really helpful

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Terminology based metadata

Document index and data catalogue

• significant thematic keywords – autoClassify()

• place names– autoClassify()

• temporal coverage– autoClassify()

this is somehow difficult to

understand

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INSPIRE: Directive for a European SDI

• “Infrastructure for Spatial Information in the European Community”• Based on OGC, ISO, W3C Standards• Built on Member States’ Spatial Data Infrastructures (SDI)• March 2007 - Directive entered in to force• Technical implementing rules on metadata; data specifications;

network services; data and service sharing; and monitoring and reporting. INSPIRE Draft Metadata Implementing Rules

http://inspire.jrc.it/whatsnew.cfm

• March 2009 – Directive transposed into national legislation• 2008 to 2012 – Phased adoption of implementing rules• 2010 to 2019 – Phased compliance with implementing rules

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Inspire metadata model

terminologyreferences

INSPIRE Draft Metadata Implementing Rules

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Inspire: abstract discovery metadataINSPIRE Draft Metadata Implementing Rules

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Inspire: Resource topic categories5.2.5 Resource topic categoryThe topic category is a high-level classification scheme to assist in the grouping and the topicbased search of available spatial resources . The applicable topic categories are defined in section 4.5.1. The specified topic category positions the resource within the framework of the INSPIRE themes given in Annexes I, II and III.

INSPIRE Draft Metadata Implementing Rules

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Inspire: Keywords

5.2.6 KeywordCommonly used word(s), formalized word(s) or phrase(s) used to describe the subject. While the topic category is too coarse for detailed queries, keywords help narrowing a full text search and they allow for structured keyword search. An ideal situation is to base this on an existing thesaurus or taxonomies. A keyword search represents a minimum search criteria defined by INSPIRE in Article 11-2 (a).

<!-- ================================================= --> <!-- System Search Keywords --> <!-- ================================================= --> <sml:keywords> <sml:KeywordList codeSpace="http://gcmd.nasa.gov/Resources/valids/keyword_list.html"> <sml:keyword>MBARI</sml:keyword> <sml:keyword>OCEANOGRAPHY</sml:keyword> <sml:keyword>MARINE SENSORS</sml:keyword> <sml:keyword>PRESSURE TRANSDUCERS</sml:keyword> <sml:keyword>SALINOMETERS</sml:keyword> <sml:keyword>THERMOMETERS</sml:keyword> <sml:keyword>CONDUCTIVITY METERS</sml:keyword> <sml:keyword>CTD</sml:keyword> </sml:KeywordList> </sml:keywords>

INSPIRE Draft Metadata Implementing Rules

Example from Sensor Web

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[2005: Referencing Keywords in Geographic Metadata]

<keyword> <MD_KeywordTypeCode codeList="http://..." codeListValue="WEU10"> Drinking Water Quality </MD_KeywordTypeCode> </keyword>

OGC Catalog Services, ISO 19115 geographic Metadata, ISO 19139 XML Schema

URL of semantic reference

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URN in the Evaluation & Use levels

• some OGC examples:

• current discussions at OGC about migrating from URN to URL

URN are not “resolvable”!

<sml:Term definition="urn:x-ogc:def:identifier:OGC:longName"> <sml:value>SBE 37-SMP MicroCAT CTP Recorder</sml:value> </sml:Term> <swe:Quantity definition="urn:x-ogc:def:property:weight"> <swe:uom code="kg"/> <swe:value>3.8</swe:value> </swe:Quantity>

<swe:Category> <gml:description>RS-485 interface allows multiple MicroCATs to share a common 2-wire cable</gml:description> <swe:codeSpace xlink:href="urn:x-ogc:def:classifiers:SBE:protocols"/> <swe:value>RS-485</swe:value> </swe:Category>

<swe:ObservableProperty definition="urn:x-ogc:def:phenomenon:OGC:temperature"> <gml:description>Sea Water Temperature</gml:description> </swe:ObservableProperty>

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What does “resolvable” mean?

1. Discovery agent finds a keyword encoded as a URL

2. Discovery agent opens URL for reading

3. “Codespace” server responds with the formal definition

4. Discovery agent tries to understand the format (OWL, RDF, any?)

5. Discovery agent reads the definition

6. Discovery agent detects Classes and ObjectProperties encoded as a URL

7. continue with 2.…

8. Discovery agent starts reasoning (“evaluating”) …

This looks much more like Representational State Transfer (REST) than like Web Services!

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Some examples of working Web Ontologies (OWL)

• MMI list of vocabularies: http://marinemetadata.org/allont

• SWEET environmental ontologies: http://sweet.jpl.nasa.gov/ontology/

• (more in the Ecoterm community)

• MMI guidance (in progress, comments welcome) on URIs/URLs -- much is aimed at ontology publishers: http://marinemetadata.org/guideontp

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MMI – a real pioneer

http://marinemetadata.org/guideontp

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Some To Dos

• Clarify the resolvable linkage between metadata and terminology

• One centralized Terminology vs. multiple “trusted” Resources

• Multilingualism: symmetric or asymmetric?

• Semantically aware discovery & evaluation agents

• Ontology Providers: become part of the infrastructure