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Ontology Work @ GeoConnections’ CGDI & CCRS’ NRCan. Brian McLeod mcleod@ccrs.nrcan.gc.ca Canada Centre for Remote Sensing. Intelec Geomatics Inc. (Montreal, Quebec). GeoInnovations (technology development program). Overview. Semantic interoperability background Ontology Service Project
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Ontology Work @ GeoConnections’ CGDI& CCRS’ NRCan Brian McLeod mcleod@ccrs.nrcan.gc.ca Canada Centre for Remote Sensing
Intelec Geomatics Inc. (Montreal, Quebec) GeoInnovations (technology development program)
Overview • Semantic interoperability background • Ontology Service Project • Context • Introduction • Objectives • Methodology • Architecture • Software • Demonstration • Next Steps
Introduction [Brodeur] • Multiplication of geospatial datasources and increased usage of geospatial information technologies • NTDB, VMap, DCF, BDTQ, OBM, Geographic Data BC; • Geospatial data and services are more and more accessible on the Web • Canadian Geospatial Data Infrastructure (CGDI), NSDI; • Today, users are turned to various geospatial data sources to fulfill their needs; • Interoperability of geospatial data and geoprocessing, proposed at the beginning of the nineties, constitutes a solution for the sharing, re-use, and integration of geospatial data(McKee and Buehler 1998; Sondheim, Gardels and Buehler 1999).
Problem [Brodeur] • Availability of multiple geospatial databases on the Web; • Each database or information community uses a specificvocabulary; • Databases are heterogeneous at syntactic, structural and semantic levels; • Many users benefit from more than one geospatial database to satisfy their needs; • Many problems such as the difficulty to locate geospatial data • Locating: search, identification, selection and extraction of geospatial data from external sources.
Spatial pictogram descriptions: :0D ; :1D ; :2D ; ?:unknown geometry ; :multiple geometry ; :alternate geometry (see [Bédard, 1999 #231] and [Brodeur, 2000 #149] for more details). 1[Natural Resources Canada, 1996 #240]; 2[VMap, 1995 #117]; 3[BC Ministry of Environment Lands and Parks (Geographic Data BC), 1992 #121]; 4[OBM, 1996 #120]; 5[Québec, 2000 #123]; 6[New Brunswick, 2000 #243]. Problem How does someone assess if the result he/she gets from his/her request corresponds to the initial perception of the reality he/she had in mind when he/she sent that request?
Context – Metadata discovery • To bridge terminology and language gaps • Search exactly the same concepts, vocabulary and language that the database uses; otherwise, their search may not yield relevant results.
Project – Multiusage, Multistandard, and Multilingual Geospatial Ontology Service • Develop a geospatial ontology service that can be used by applications and other services • The project was funded in March 2003 under the CGDI GeoInnovations program
Objectives • Examine requirements related to geospatial ontologies • Identify the operations that a service must fulfill to meet requirements • Define Web protocols to access the service • Develop the service using interoperability standards • Technology assessment
Participants • Developers • CRG, Université Laval • Intelec Geomatics • Users • Ministry of National Defence • Ministère des Ressources naturelles du Québec • Ministry of Fisheries and Oceans (CHS • Natural Resources Canada (CTI-S & CCRS) • NatureServe Canada • Environment Canada • Commission for Environmental Cooperation
Inputs • Scope • Language known by client (service) • Ontology of keywords • Ontology in text or DBMS • Initial Content (GCMD-bilingual, IHO B6 and S57) • Guide for building ontologies • UTF-8 for character encoding
Protégé - software related • Free, open source, java • Customizable editor • Plugins can be added • Database can be accessed by an API
Protégé can be used for the following • Class modeling. Protégé provides a graphical user interface (GUI) that models classes (domain concepts) and their attributes and relationships. • Instance editing. From these classes, Protégé automatically generates interactive forms that enable you or domain experts to enter valid instances. • Model processing. Protégé has a library of plug-ins that help you define semantics, perform queries, and define logical behavior. • Model exchange. The resulting models (classes and instances) can be loaded and saved in various formats, including XML, UML, and RDF (Resource Description Framework). Protégé also provides a scalable database back end.
Operations • GetCapabilities • GetOntology • GetDefinition • GetPrefered • GetSimilar • GetTranslation • GetGraph
Demonstration http://intelecgeomatics.com:8080/ogm3/default.jsp
Thank you Questions ??
M3GO Protégé-2000 Presentation
Protégé - software related • Free, open source, java • Customizable editor • Plugins can be added • Database can be accessed by an API
Protégé can be used for the following • Class modeling. Protégé provides a graphical user interface (GUI) that models classes (domain concepts) and their attributes and relationships. • Instance editing. From these classes, Protégé automatically generates interactive forms that enable you or domain experts to enter valid instances. • Model processing. Protégé has a library of plug-ins that help you define semantics, perform queries, and define logical behavior. • Model exchange. The resulting models (classes and instances) can be loaded and saved in various formats, including XML, UML, and RDF (Resource Description Framework). Protégé also provides a scalable database back end.
Metaclasses M3GO implementation inside Protégé is composed of 3 metaclasses: • ONTOLOGIE • CONCEPT • NOM • A metaclass is a template, or a class whose instances are themselves classes
Each metaclass is defined by a set of attributes called slots
Subclasses • M3GO uses 11 subclasses to implement the model • Each subclass is also defined by a series of properties (slots)
Adding a slot Slots are properties or relationships between classes
Building an Ontology Building an ontology is done by implementing previously defined metaclasses in a hierarchical manner
Protégé’s plugins • Storage • CLIPS • XML • XML Schema • RDF • OIL (Ontology Inference Layer) • DAML+OIL • UML • XMI • Visualization • Jambalaya • TGVizTab • OntoViz • Project and file management • BeanGenerator • DataGenie • Prompt • Etc.
Thank you Questions ??