Semantic Web Course Introduction Vagan Terziyan Department of

Semantic Web Course Introduction Vagan Terziyan Department of Mathematical Information Technology, University of Jyvaskyla vagan@it. jyu. fi ; terziyan@yahoo. com http: //www. cs. jyu. fi/ai/vagan +358 14 260 -4618 ITIN, France, February 2006

Contents § § Course introduction Practical information Lectures Course exercise 2

Course Introduction: Semantic Web - new Possibilities for Intelligent Web Applications 3

Motivation for Semantic Web 4

Semantic Web Content: New “Users” applications agents 5

Semantic Web: Resource Integration Semantic annotation Shared ontology Web resources / services / DBs / etc. 6

Semantic Web: which resources to annotate ? Industrial and business processes Web resources / services / DBs / etc. Web users (profiles, preferences) Web access devices Shared ontology External world resources Multimedia resources Web agents / applications Smart machines and devices 7

Word-Wide Correlated Activities Semantic Web is an extension of the current web in which information is given well-defined meaning, better enabling computers and people to work in cooperation Agentcities is a global, collaborative effort to construct an open network of on-line systems hosting diverse agent based services. Agentcities Grid Computing Wide-area distributed computing, or "grid” technologies, provide the foundation to a number of large-scale efforts utilizing the global Internet to build distributed computing and communications infrastructures. Web Services WWW is more and more used for application to application communication. The programmatic interfaces made available are referred to as Web services. The goal of the Web Services Activity is to develop a set of technologies in order to bring Web services to their full potential FIPA is a non-profit organisation aimed at producing standards for the interoperation of heterogeneous software agents. 8

Semantic Technology Semantic technology as a software technology allows the meaning of information to be known and processed at execution time. For a semantic technology there must be a knowledge model of some part of the world that is used by one or more applications at execution time. 9

Semantic Technology Market Forecasting Semantic solution, services & software markets will grow rapidly, topping $60 B by 2010. 10

Excellent Job Opportunities: Samples of Mail-List with Job Advertisements Onto. Web (at least 2 -3 job advertisements on Semantic Web and Web Services Technologies in Europe per week!) ontoweb-list@lists. deri. org To register follow the link: http: //lists. deri. org/mailman Semantic Web (at least 2 -3 job advertisements on Semantic Web and Web Services Technologies in Europe per week!) seweb-list@lists. deri. org To register follow the link: http: //lists. deri. org/mailman 11

Course Description 12

Practical Information Lectures: 10 hours Monday: 20 February, 9: 00 -10: 15; 10: 30 -12: 00; 13 h 30 -15 h 15; Tuesday: 21 February, 9: 00 -10: 15; 10: 30 -12: 00. Slides available online (links from Introductory Lecture) Exercise: 6 hours Monday: 20 February, 15: 30 -17: 00 Tuesday: 21 February, 13: 30 -15: 15; 15: 30 -17: 00. task will be announced during the lectures 13

Lectures 14

Semantic Web Lectures Schedule 20/02/2006 (9: 00 - 10: 15) – Lecture 1: Semantic Web Basics 20/02/2006 (10: 30 - 12: 00) – Lecture 2: Semantic Web Applications 20/02/2006 (13: 30 - 15: 15) – Lecture 3: Protege Tutorial (Designing Ontologies with Protege) 21/02/2006 (9: 00 - 10: 15) – Lecture 4: Semantic Web Services Basics 21/02/2006 (10: 30 - 12: 00) – Lecture 5: Industrial Smart Resources in Semantic Web 15

Introduction http: //www. cs. jyu. fi/ai/vagan/SW_Introduction. ppt 16

Lecture 1: Semantic Web Basics http: //www. cs. jyu. fi/ai/Onto. Group/pres/SW_Tutorial_2004_Part_1. ppt http: //www. cs. jyu. fi/ai/vagan/Semantic_Web. ppt 17

Lecture 2: Semantic Web Applications http: //www. cs. jyu. fi/ai/Onto. Group/pres/SW_Tutorial_2004_Part_2. ppt 18

Lecture 3: Tutorial: Designing Ontologies with Protégé § Protégé is an ontology editor and a knowledgebase editor (download from http: //protege. stanford. edu ). § Protégé is also an open-source, Java tool that provides an extensible architecture for the creation of customized knowledge-based applications. § Protégé's OWL Plug-in now provides support for editing Semantic Web ontologies. http: //www. cs. man. ac. uk/~horrocks/Teaching/cs 646/ http: //www. co-ode. org/resources/tutorials/Protege. OWLTutorial. pdf 19

Lecture 4: Semantic Web Services Basics http: //www. cs. jyu. fi/ai/vagan/Why_SWS. ppt 20

Lecture 5: Industrial Smart Resources in Semantic Web http: //www. cs. jyu. fi/ai/vagan/Smart. Resource_Summary. ppt 21

Additional Material for Self-Study

Just for case you do not know: Introduction to XML http: //www. cs. jyu. fi/ai/vagan/XML. ppt 23

Markup Techniques http: //www. cs. jyu. fi/ai/vagan/Markup_Techniques. ppt 24

RDF and RDF Schema http: //www. cs. jyu. fi/ai/vagan/RDF. ppt 25

Ontologies in Semantic Web http: //www. cs. jyu. fi/ai/vagan/Ontologies_1. ppt http: //www. cs. jyu. fi/ai/vagan/Ontologies_2. ppt 26

JENA § Jena is a Java framework for building Semantic Web applications. It provides a programmatic environment for RDF, RDFS and OWL, including a rule-based inference engine. § Jena is open source and grown out of work with the HP Labs Semantic Web Program. § The Jena Framework includes: l l l A RDF API Reading and writing RDF in RDF/XML, N 3 and N-Triples An OWL API In-memory and persistent storage RDQL – a query language for RDF http: //jena. sourceforge. net/tutorial/RDF_API/index. html http: //jena. sourceforge. net/ 27

Jena Integration of Protégé-OWL § Jena is one of the most widely used Java APIs for RDF and OWL, providing services for model representation, parsing, database persistence, querying and some visualization tools. Protege-OWL always had a close relationship with Jena. The Jena ARP parser is still used in the Protege-OWL parser, and various other services such as species validation and datatype handling have been reused from Jena. It was furthermore possible to convert a Protege OWLModel into a Jena Ont. Model, to get a static snapshot of the model at run time. This model, however had to be rebuild after each change in the model. § As of August 2005, Protege-OWL is now much closer integrated with Jena. This integration allows programmers to user certain Jena functions at run-time, without having to go through the slow rebuild process each time. The architecture of this integration is illustrated on the next slide… http: //protege. stanford. edu/plugins/owl/api/guide. html 28

Jena Integration of Protégé-OWL The key to this integration is the fact that both systems operate on a lowlevel "triple" representation of the model. Protege has its native frame store mechanism, which has been wrapped in Protege-OWL with the Triple. Store classes. In the Jena world, the corresponding interfaces are called Graph and Model. The Protege Triple. Store has been wrapped into a Jena Graph, so that any read access from the Jena API in fact operates on the Protege triples. In order to modify these triples, the conventional Protege-OWL API must be used. However, this mechanisms allows to use Jena methods for querying while the ontology is edited inside Protege. The OWLModel API has a new method get. Jena. Model() to access a Jena view of the Protege model at 29 run-time. This can be used by Protege plugin developers. Many other Jena services can be wrapped into Protege plugins this way, by providing them a pointer to the Model created by Protege.

Joseki - a SPARQL Server for Jena § Joseki: The Jena RDF Server. Joseki is a server for publishing RDF models on the web. Models have URLs and they can be access by HTTP GET. Joseki is part of the Jena RDF framework. § Joseki is an HTTP and SOAP engine supports the SPARQL Protocol and the SPARQL RDF Query language. SPARQL is developed by the W 3 C RDF Data Access Working Group. § Joseki Features: l l l RDF Data from files and databases HTTP (GET and POST) implementation of the SPARQL protocol SOAP implementation of the SPARQL protocol http: //prdownloads. sourceforge. net/joseki-3. 0 -beta-1. zip? download http: //www. joseki. org/ 30

Course Exercise 31

Task for the Exercise (6 x 45 min) § Learn to use Protégé (45 min) – personal work; § Create ontology for companies description based on Protégé tool (work in 4 groups, 5 persons per group all from different companies) (45+45 min); § semantically annotate your employer company based on ontology of your group – personal work (45 min); § Recreate groups so that each new group contains one representative from each previous group (i. e. it will be 5 groups, 4 persons per group), each group independently tries to integrate 4 original ontologies and appropriate semantic descriptions to one ontology in Protégé, printing final files to the report (45+45 min). 32

Lecture Notes and Textbook Lecture Notes (available online) Follow link: http: //www. cs. jyu. fi/ai/vagan/courses Main recommended textbook Dave Mc. Comb, Semantics in Business Systems, Morgan Kaufmann, 2004. 33

Additional Reading Johan Hjelm, “Creating the Semantic Web with RDF”, John Wiley, 2001 Dieter Fensel: “Ontologies: A Silver Bullet for Knowledge Management and Electronic Commerce”, Springer Verlag, 2001 John Davies, Dieter Fensel & Frank van Harmelen: , “Towards the Semantic WEB – Ontology Driven Knowledge Management”, John Wiley, 2002 Dieter Fensel, Wolfgang Wahlster, Henry Lieberman, James Hendler (Eds. ): “Spinning the Semantic Web: Bringing the World Wide Web to Its Full Potential”, MIT Press, 2002 Thomas B. Passin, "Explorer's Guide to the Semantic Web", ISBN 1932394206, June 2004 Jeff Pollock and Ralph Hodgson, "Adaptive Information: Improving Business Through Semantic Interoperability, Grid Computing, and Enterprise Integration“, Wiley Computer Publishing, September 2004 Michael C. Daconta, Leo J. Obrst, Kevin T. Smith: “The Semantic Web: A Guide to the Future of XML, Web Services, and Knowledge Management”, John Wiley, 2003 M. Klein and B. Omelayenko (eds. ), “Knowledge Transformation for the Semantic Web”, Vol. 95, Frontiers in Artificial Intelligence and Applications, IOS Press, 2003 34

Where to find out more: Web-Sites § OWL, OWL-S l l http: //www. w 3. org/2004/01/sws-pressrelease http: //www. w 3. org/2004/01/sws-testimonial § Semantic Web l l http: //www. w 3. org/2001/sw/ http: //www. semwebcentral. org/ § Semantic Web Services l l l http: //www. daml. org/services/ http: //www. swsi. org/ http: //www. wsmo. org 35