A Perspective for Semantic Web Research and Development

© 2005 François Bry

The teaching material made available here is exclusively for private use and for use within REASE, the Repository of EASE for Learning Units. No part of it may be distributed in classes, or in publications, reproduced, stored in a retrieval system, or published, in any form or by means electronic, mechanical, photocopying, or otherwise, without prior written permission of the authors.

Contents

  1. A Car Renting Scenario
  2. Beyond Ontology Reasoning
  3. Summer School Programme
  4. Acknowledgment

1 A Car Renting Scenario

Car renting price regulations for company customers:

  • No more than 20 cars rented at once at (reduced) company price.
  • No company price on Class A cars.

General car renting regulations:

  • No more than one car rented at once by a person.
  • No price reductions for young drivers (i.e. < 26 years).

Company regulations:

  • Junior employees are at most 24 years old.
  • Every employee is junior or senior employee.
  • Senior employees rent only Class A cars.

The above regulations are expressible in OWL-DL (but not in RDF).

The above regulations are realistic although simplified, cf. [EU Rent].

2 Beyond Ontology Reasoning

Desirable forms of reasoning:

  • Draw the conclusion that an employee older than 25 years is a senior employee
    → Excluded middle needed.
  • Draw the conclusion that no junior employee can rent a car on the (reduced) company price.
    → Refutation needed
    → Monotonic negation needed
  • Check whether a regulation, say "No more than 20 cars rented at once at (reduced) company price." is currently enforced. For sure, it can be violated from time to time!
    → Non-monotonic negation ("SNAF") needed!
    → Integrity constraints and integrity checking
  • Determine the "gold customers", i.e. customers having rent cars at least 5 times during the last 12 months.
    → Constructive reasoning, i.e. excluded middle and refutation not needed
    → (Database) view

Salient aspects:

  • One syntax but two forms of reasoning for negation: "No more than 20 cars rented at once at (reduced) company price."
  • Reasoning with regulations
    • at various Web sites, possibly known only at "query" or "deduction time.
      → Backward reasoning needed
    • and expressed in various languages, e.g. RDF, OWL, XML.
      → Versatile Query Languages needed
  • Beyond Ontology Reasoning:
    • Backward chaining for querying views
    • Integrity checking (→ querying views)
    • View updates (i.e. what can be changed in the regulation for preventing John Smith of being a "gold customer"?)
    • View materialization (a beloved issue in the "forward chaining addict" RDF community)
    • Update propagations on the distributed Web without central management
    • Specifying reactive behaviours on the distributed Web without central management
    • Specifying policies and reasoning with policies, e.g. conditions under which one gives his credit card number
    • Reasoning for personalization
    • Reasoning for information extraction
    • Modeling "ontologies", "regulations", "business rules", etc. and their markup
    • Natural language-like expressions of "regulations" (or "business rules")
    • Type inference for static type checking
    • Special theories, e.g. for temporal data and calendars as well as (simple) arithmetics
    • etc.

Some views mentioned in this introduction might be controversial → let us dicuss!

3 Summer School Programme and Lecturers

  • A Perspective for Semantic Web Research and Development
    François Bry
  • Fundamentals of Semantic Web Ontology Languages
    Grigoris Antoniou and Enrico Franconi
  • Programming with Logic and Objects
    Michael Kifer
  • Web and Semantic Web Query Languages: Standards, State of the Art, and Perspectives
    James Bailey, François Bry, Tim Furche, and Sebastian Schaffert
  • Reuse in Semantic Web Applications
    Uwe Aßmann
  • Rule Modelling and Markup
    Gerd Wagner
  • Personalization for the Semantic Web
    Matteo Baldoni and Nicola Henze
  • Information Extraction for the Semantic Web
    Robert Baumgartner
  • Types in the Semantic Web
    Włodzimierz Drabent
  • Evolution and Reactivity for the Web
    Wolfgang May and José Júlio Alferes
  • Attempto Controlled English
    Norbert E. Fuchs

This programme reflects part of of the undergoing work in the reasearch project REWERSE.

4 Acknowledgment

Thanks to

  • the lecturers for their lectures and articles,
  • the Malta staff, especially Mike Rosner, for the local organization,
  • Jan Małuszyński and Norbert Eisinger or the planing of the Summer School and proceedings,
  • to the attendance for working with us!

The Summer School Reasoning Web 2005 has been funded by the European Commission and by the Swiss Federal Office for Education and Science within the 6th Framework Programme project REWERSE number 506779.

Bibliography

[EU-Rent] The Business Rules Group
Defining Business Rules ~ What Are They Really?
2001 http://www.businessrulesgroup.org/first_paper/br01c0.htm
Last modified: Wed Jul 20 12:55:42 CEST 2005   Valid XHTML 1!   Valid CSS!