Usted está aquí: Inicio Ingeniería Telemática Web 2.0 and Web 3.0 Technologies Module 3 Project

Module 3 Project

Acciones de Documento
  • Vista de contenidos
  • Marcadores (bookmarks)
  • Exportación de LTI
Autores: Luis Sánchez Fernández, Carlos Delgado Kloos, Vicente Luque Centeno, José Jesús García Rueda, Norberto Fernández García

RDF Resource Description Framework Flyer Icon Module 3: Semantic Web and Ontologies


Scenario Scenario

An university want to provide additional functionalities to its Web server:

 

  • Powerful and precise search capabilities

  • Navigation through semantically related items.

  • ...

It is decided to use Semantic Web technologies. As a first step an ontology is being developed that models the main concepts related to the content available in the Web server: people, courses, etc. Such ontology will also be used to check the consistency of the information available in the Web server.

Abstract_pic Abstract

In this module we are going to learn:

  1. What is the Semantic Web.

  2. The Semantic Web architecture.

  3. Semantic Web standard languages to represent knowledge and ontologies: RDF, RDF Schema, OWL.

  4. Techniques and tools to develop ontologies.

Deliverables_pic Deliverables

  1. Write an OWL-DL ontology using the Protégé editor, that models concepts and relations involved in the university domain. Below you can find a textual description that summarises the aspects you have to model:

    University concepts to be modelled:

    • Related to university degrees: University degrees can be classified in three categories: Bachelor and Master and PhD. Master students have to have a Bachelor degree. Bachelor and Master students have to study some courses to get their degree. When thay have passed all the required degree courses, they should make a Master or Bachelor Thesis, respectively, to get their degree. To get a PhD students have to have a Master degree. They have to make a PhD Thesis to get the PhD degree. Each course has a number of students and a number of University teachers. A Bachelor course teacher should have a Bachelor Degree. A Master course teacher should have a Master degree. Each course has a single coordinator. Coordinators should be either Permanent Professors or teaching Assistants that have a PhD degree or Associate Professors.

    • Related to university people: people related to an university can be classified in two categories: university employees (people that works at the university) and students. University employees are university teachers and administrative staff. Administrative staff cannot lecture in university courses. University teachers have to teach in some university courses. University teachers can be Permanent Professors, Assistants and Associate Professors. Permanent Professors have to have a PhD degree. They are university permanent full-time employees. They cannot have another job. Assistants have to have a Bachelor degree. They are temporal University full-time employees. They also cannot have another job. Associate Professors are temporal part-time employees that work also in a Company.

    The requested ontology should extend this Simple University Ontology. This ontology defines the following classes and properties:

    • Classes:

      • Person: class of all human beings.

      • University: class of all universities.

      • Company: class of all organizations created to conduc business.

      • Degree: class of all educational programs offered by universities. To get a degree usually is necessary to pass some courses and write a thesis.

      • Course: class of all university courses.

    • Properties:

      • hasCoordinator: relates a course with its coordinator.

      • worksAt: relates a person with the institution where he/she has a job.

      • isPermanentEmployeeOf: relates a person with the institution where he/she has a permanent job.

      • studies: relates a person with one of the courses she/he studies.

    Note:When extending the Simple University Ontology you can define axioms for already defined classes and properties.

    Document the developed ontology.

  2. Extend the ontology you have defined in deliverable 1 to model the rules that should be fulfilled to get the Máster Interuniversitario en Ingeniería Telemática degree, jointly organized by Carlos III University and Technical University of Catalonia.

    You will find that it is difficult, even impossible, to model some of the rules in OWL-DL. Describe which difficulties have you found.

    Document the developed ontology.

Strategy_picStrategy

  1. Complete the overview on the Semantic Web presented in the first session of the module reading the documents referenced in items 1 and 2 in the resources section.

  2. Install Protégé (item 4 in the resources section) and Pellet (item 5 in the resources section). Follow these installation instructions.

  3. Make the tutorial referenced in item 3 in the resources section.

  4. To develop the requested ontologies you should follow these steps:

    1. Get a textual description of the world you want to model (in the case of the first ontology this textual description is provided).

    2. From the textual description, think in different scenarios where you can extract new information about some entity based on the information contained in the textual description. Fonr instance, according to the textual description provided for the first ontology, if we know that somebody lectures in some university course and is a permanent employee of some university we can conclude that she/he is a Permanent Professor.

    3. From the textual description, identify relevant concepts and relations involved in the case study.

    4. Add classes to the ontology to model de identified concepts. In our case, usually such classes will be subclasses of the classes available in the provided ontology. Add properties in the ontology to model the identified relations. Whenever possible define each property domain and range.

    5. Provide definitions for the ontology classes and add axioms to the ontology. Try to model in the ontology as much of the information contained in the textual description as possible.

    6. Check that your ontology can deal with the scenarios in point 2. If necessary repeat steps 3 to 6.

    Note: you can learn more on methodologies and methods to build ontologies from the book referenced in item 6 in the resources section.

Questions_picQuestions

  1. Using the provided bibliography and Internet find 3 different systems or applications that make use of Semantic Web technologies. Discuss the role in each application (if any) of ontologies, annotations and reasoning.

  2. Why XML cannot be used instead of RDF for knowledge representation in Semantic Web applications?

  3. Which are the differences between the three versions of OWL: OWL-Lite, OWL-DL and OWL-Full?

Resources_picResources

  1. Tim Berners-Lee, James Hendler and Ora Lassila: The Semantic Web. Scientific American, May 2001.

  2. Luis Sánchez-Fernández and Norberto Fernández-García: The Semantic Web: Fundamentals and A Brief State-of-the-Art. UPGRADE, Vol. VI, issue 6, December 2005.

  3. Matthew Horridge, Holger Knublauch, Alan Rector, Robert Stevens and Chris Wroe: A Practical Guide To Building OWL Ontologies Using The Protégé-OWL Plugin and CO-ODE Tools. Edition 1.0, August 2004.

  4. The Protégé Ontology Editor and Knowledge Acquisition System. It is recommended to use Protégé version 3.3.1.

  5. Pellet: The Open Source OWL DL Reasoner

  6. Asunción Gómez Pérez, Mariano Fernández López, Óscar Corcho: Ontological Engineering (with examples from the areas of Knowledge Management, e-Commerce and the Semantic Web). Srpinger, 2004.

  7. RDF Primer. W3C Recommendation 10 February 2004.

  8. RDF/XML Syntax Specification (Revised). W3C Recommendation 10 February 2004.

  9. RDF Vocabulary Description Language 1.0: RDF Schema. W3C Recommendation 10 February 2004.

  10. OWL Web Ontology Language Reference. W3C Recommendation 10 February 2004.

  11. Journal of Web Semantics, Elsevier.

  12. International Semantic Web Conference.

  13. European Semantic Web Conference.

Reutilizar Curso
Descargar este curso