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Ecoterm IV - Vienna. ECO. EcoInformatics Initiative. Ecoterm IV – Vienna 17 – 18 April 2007. 1. Semantic Integration of Environmental Data Herbert Schentz. START. Overview. Integrating Environmental Data Why We Need Semantics Helpful Technologies Ontologies in Networks
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Ecoterm IV - Vienna ECO EcoInformatics Initiative Ecoterm IV – Vienna 17 – 18 April 2007 1
Semantic Integration of Environmental Data Herbert Schentz START
Overview • Integrating Environmental Data • Why We Need Semantics • Helpful Technologies • Ontologies in Networks • Final Considertions
Data are often stored in different databases at different sites
Lots of questions are not even posed because getting data is too difficult ?
Overview • Integrating Environmental Data • Why We Need Semantics • Helpful Technologies • Ontologies in Networks • Final Considertions
When you want to integrate the data many questions arise How was measuring (observation) done ? Which unit ? Which vegetation layer?, soil layer?, species ? How were the measurement sites selected ? When was the measurement done ? How often was the measurement repeated ? Who did the measurement ? Which important measurement was done in parallel ? Within which project was it done ? Special circumstances of measurement ? .... ... the meaning of data and metadata !
attached Information ? It would be fine if the data would have attached something similar to the bar-code of products which allows to identify a lot of qualities of the product just by reading it
Meaning is a sample of terms with relations between them main deliverer producer product declarations product name transport stock price
lies in measured in has value has value Meaning is a sample of terms with relations between them limit of detection .... in unit vegetation layer with limit of dedection in value species measured for measured on parameter Measurement site
We need a connection from the data to a description of their meaning People who share a common description of the meaning of the data (common ontology) and have a common protocol for the interconnection can instantly correctly share their data. ontology
Interfaces, Thesauri, Metadata, Ontologies Metadata Thesauri Machine readability More relations and rules + semantic interoperability Ontologies Interfaces Knowledge Representation
Overview • Integrating environmental Data • Why we need Semantics • Helpful Technologies • Ontologies in Networks • Final Considertions
Technologies of the Semantic Web The technologies of the semantic web can help us: They are designed to • build structures that express meaning • share those structures • connect resources distributed all over the web • be extended The basic construct is the RDF (Resource Description Framework) - triple
RDF – the tripples tail leg head child has has has bears mamal is a is a Cat mouse hunts
Another set of RDF tripples site parameter method layer what how where On what Soil measurement when result value timestamp
site S120A Mg parameter AAS method Layer B layer what what how how where where On what On what Soil measurement S120A_Mg_2000 when when result result 0.003 value 2000-06-04 timestamp RDFS / OWL the classes of tripples Definition = Class = OWL / RDFS Special Thing = instance = RDF
Features of RDFS / OWL (1) Classes can be inhertited animal isA mammal isA rodent isA Which means that mouse can always be treated as a rodent as a mammal as an animal Wherever rodent is allowed , mouse is allowed too (Polymorphism) mouse
WWW Features of RDF / RDFS / OWL (2) All Entities (Classes, Relations, Instances can be distributed over several namespaces) GBIF ALTERRA (NL) ontology on birds ontology on vegetation regions Umweltbundesamt (A) ontology on birdwatching sites
Features of OWL (3) Relations can have restrictions (cardinalities,...) hunt cat mouse some has mammal head 1 all
RDF / RDFS / OWL RDF / RDFS and OWL are W3C recomandations • They are constructed to be especially effective • within the web (distributed ontologies) • Lots of Communities are adopting them as standards • Several tools exist for working with them: • Editors • Mapping tools rdbs – ontologies • Mapping tools ontologies – GISs • Transformation Tools XSDs Ontologies • ……
Overview • Integrating Environmental Data • Why We Need Semantics • Helpful Technologies • Ontologies in Networks • Final Considertions
What else do we need ? mappings Data that can be linked to ontologies query engines search engines (geo) graphical displays ...... ontologies
Massflow Calculation I integrating environmental applications ontology Allowed Substances „Heavy Metals“ Allowed Plants „Vascular Plants“ & „Mosses“ Allowed Soil „Rentsina“ Allowed gographical Region „Alpine Region“ Ouput „Distribution“ after time t in „days“ With semantically defined interfaces of webservices „SAWSDL“
What do we need to build ontologies Thesauri Metadata Structures Tools for collaborative developement of ontologies Existing ongologies Knowledge Collaboration efforts
Overview • Integrating Environmental Data • Why We Need Semantics • Helpful Technologies • Ontologies in Networks • Final Considertions
The socio- political component „.... This is more a social task than a technical task“, Midori Harris said at a conference on Ontologies in Edinburgh. We all knocked our heads. – so did I- and We went home to work on our technical solutions.
Vicious circle Bad interoperability --> little datasharing --> lack of resources --> little acknowledgement --> little output -->
more acknowledgement Good interoperability Positive spirale more output more interoperability more datasharing more output better interoperability more acknowledgement more resources Semantic Interoperability Based on Ontologies more datasharing
Ecoterm IV - Vienna ECO Thank you for your attention EcoInformatics Initiative I wish us a fruitfull conference herbert.schentz@umweltbundesamt.at http://www.umweltbundesamt.at Ecoterm IV – Vienna 17 – 18 April 2007 32