Semantic Web Rules

This book constitutes the refereed proceedings of the Third International Workshop on Rules and Rule Markup Languages for the Semantic Web, RuleML 2004, held in Hiroshima, Japan, in November 2004, together with ISWC 2004. The 11 revised full papers presented together with 2 invited papers and 5 tool presentation abstracts were carefully reviewed and selected from 25 submissions. Among the topics addressed are nonmonotonic rule systems, rule learning for feature extraction, logic reasoners for the Semantic Web, deductive RDF rule languages, description logic programs, defeasible description logics, conceptual logic programs, OWL inferencing, and Semantic Web reasoning.

A new edition of the widely used guide to the key ideas, languages, and technologies of the Semantic Web The development of the Semantic Web, with machine-readable content, has the potential to revolutionize the World Wide Web and its uses. A Semantic Web Primer provides an introduction and guide to this continuously evolving field, describing its key ideas, languages, and technologies. Suitable for use as a textbook or for independent study by professionals, it concentrates on undergraduate-level fundamental concepts and techniques that will enable readers to proceed with building applications on their own and includes exercises, project descriptions, and annotated references to relevant online materials. The third edition of this widely used text has been thoroughly updated, with significant new material that reflects a rapidly developing field. Treatment of the different languages (OWL2, rules) expands the coverage of RDF and OWL, defining the data model independently of XML and including coverage of N3/Turtle and RDFa. A chapter is devoted to OWL2, the new W3C standard. This edition also features additional coverage of the query language SPARQL, the rule language RIF and the possibility of interaction between rules and ontology languages and applications. The chapter on Semantic Web applications reflects the rapid developments of the past few years. A new chapter offers ideas for term projects. Additional material, including updates on the technological trends and research directions, can be found at http://www.semanticwebprimer.org.

The Semantic Web represents a vision for how to make the huge amount of information on the Web automatically processable by machines on a large scale. For this purpose, a whole suite of standards, technologies and related tools have been specified and developed over the last couple of years and they have now become the foundation for numerous new applications. A Developer’s Guide to the Semantic Web helps the reader to learn the core standards, key components and underlying concepts. It provides in-depth coverage of both the what-is and how-to aspects of the Semantic Web. From Yu’s presentation, the reader will obtain not only a solid understanding about the Semantic Web, but also learn how to combine all the pieces to build new applications on the Semantic Web. The second edition of this book not only adds detailed coverage of the latest W3C standards such as SPARQL 1.1 and RDB2RDF, it also updates the readers by following recent developments. More specifically, it includes five new chapters on schema.org and semantic markup, on Semantic Web technologies used in social networks and on new applications and projects such as data.gov and Wikidata and it also provides a complete coding example of building a search engine that supports Rich Snippets. Software developers in industry and students specializing in Web development or Semantic Web technologies will find in this book the most complete guide to this exciting field available today. Based on the step-by-step presentation of real-world projects, where the technologies and standards are applied, they will acquire the knowledge needed to design and implement state-of-the-art applications.

The Semantic Web is a worldwide endeavor to advance the Web by enriching its content with semantic metainformation that can be processed by inferen- enabled Web applications. Taxonomies and rules, along with their automated reasoning techniques, are the main components of Semantic Web ontologies. Rule systems are considered to be a major area in the further development of the Semantic Web. On one hand, rules can specify declarative knowledge in ontology languages, expressing constraints or transformations, either in conju- tionwith,orasanalternativeto,descriptionlogics.Ontheotherhand,rulescan specify behavioral knowledge, enforcing policies or reacting to events/changes. Finally, rule markup languages such as RuleML allow us to publish rules on the Web, to process rules in general XML environments as well as special rule engines, to exchange rules between di?erent applications and tools via XSLT translators, as well as to embed rules into other XML content and vice versa. This workshop was dedicated to all aspects of rules and rule markup l- guages for the Semantic Web. RuleML 2004 was the third in a series of wo- shops that was initiated with the International Semantic Web Conference. The previous workshops were held on Sardinia, Italy (2002), and on Sanibel Island, USA (2003). Thisyearwehad25submissions,ofwhich11wereacceptedasregularpapers and another ?ve as short papers describing tools. Wearegratefultoourtwoinvitedspeakers,MikeDeanfromBBNandChr- tine Golbreich from the University of Rennes. Our thanks also go to all subm- ters and reviewers without whom the workshop and these proceedings could not have succeeded.

With more substantial funding from research organizations and industry, numerous large-scale applications, and recently developed technologies, the Semantic Web is quickly emerging as a well-recognized and important area of computer science. While Semantic Web technologies are still rapidly evolving, Foundations of Semantic Web Technologies focuses

RuleML 2003 was the second international workshop on rules and rule markup languages for the Semantic Web, held in conjunction with the International Semantic Web Conference (ISWC). The aim of the RuleML workshop series is to stimulate research on all issues related to web rule languages and to provide an annual forum for presenting and discussing new research results. The Semantic Web is a major world-wide endeavor to advance the Web by enriching its multimedia document content with propositional information that can be processed by inference-enabled Web applications. Rules and rule markup languages, such as RuleML, will play an important role in the success of the Semantic Web. Rules will act as a means to draw inferences, to express constraints,tospecifypoliciesforreactingtoevents,totransformdata,etc.Rule markup languages will allow us to enrich Web ontologies by adding de?nitions of derived concepts, to publish rules on the Web, to exchange rules between di?erent systems and tools, etc. RuleML 2003 built on the success of RuleML 2002, which was held in c- junction with ISWC 2002, Sardinia, Italy. The proceedings of RuleML 2002 can be found at http://www.ceur-ws.org/Vol-60/. Special highlights of the RuleML 2003 workshop were the two invited pres- tationsgivenbyPeterChenon“Rules,XML,andtheERModel”andbyHarold Boley on “Object-Oriented RuleML: User-Level Roles, URI-Grounded Clauses, and Order-Sorted Terms”. This proceedings volume also contains an invited - per by Francois ̧ Bry and Sebastian Scha?ert on “An Entailment Relation for Reasoning on the Web”.

RuleML 2005 was the ?rst international conference on rules and rule markup languages for the Semantic Web, held in conjunction with the International Semantic Web C- ference (ISWC) at Galway, Ireland. With the success of the RuleML workshop series came the need for extended research and applications topics organized in a conference format. RuleML 2005 also accommodated the ?rst Workshop on OWL: Experiences and Directions. Rules are widely recognized to be a major part of the frontier of the Semantic Web, and critical to the early adoption and applications of knowledge-based techniques in- business, especially enterprise integration and B2B e-commerce. This includes kno- edge representation (KR) theory and algorithms; markup languages based on such KR; engines, translators, and other tools; relationships to standardization efforts; and, not least, applications. Interest and activity in the area of rules for the Semantic Web has grown rapidly over the last ?ve years. The RuleML 2005 Conference was aimed to be this year’s premiere scienti?c conference on the topic. It continued in topic, leadership, and collaboration with the previous series of three highly successful annual inter- tional workshops (RuleML 2004, RuleML 2003 and RuleML 2002). The theme for RuleML 2005 was rule languages for reactive and proactive rules, complex event p- cessing, and event-driven rules, to support the emergence of Semantic Web applications. Special highlights of the RuleML 2005 conference included the keynote address by Sir Tim Berners- Lee, Director of W3C.

The next major advance in the Web-Web 3.0-will be built on semantic Web technologies, which will allow data to be shared and reused across application, enterprise, and community boundaries. Written by a team of highly experienced Web developers, this book explains examines how this powerful new technology can unify and fully leverage the ever-growing data, information, and services that are available on the Internet. Helpful examples demonstrate how to use the semantic Web to solve practical, real-world problems while you take a look at the set of design principles, collaborative working groups, and technologies that form the semantic Web. The companion Web site features full code, as well as a reference section, a FAQ section, a discussion forum, and a semantic blog.