====== RDF ======
===== Before the lab =====
=== Reading: ===
   * Quick introduction  [[http://www.w3schools.com/rdf/rdf_intro.asp| by w3schools]] 
   * [[ http://www.inf.unibz.it/~debruijn/teaching/swt/lecture-1-handouts.pdf|RDF ]] and [[http://www.inf.unibz.it/~debruijn/teaching/swt/lecture-2-handouts.pdf|RDFS]]
   * [[http://www.cs.rpi.edu/~puninj/XMLJ/classes/class8/all.html| RDF and RDFS summary]]

Further reading:
   * [[http://www.w3.org/TR/2003/PR-rdf-primer-20031215/| RDF Primer]] by w3.org


=== Control questions: ===
   * what are:
       * resources, 
       * properties, 
       * statesmets.
   * what does RDF use to identify resources?
   * what are the required elements of RDF file?
   * what are namespaces, how they are defined and what they are used for?
   * what listed tags are used for:
       * <rdf:Description>
       * <rdf:about>
       * <rdf:resource> 
       * <rdf:type>
   * what container elements are available in RDF?
   * what is RDF Schema?
   * what are core RDFS Classes and properties?
   * how constraints on domain and range of properties are added?
===== Lab instructions 1 =====
==== Basic RDF and RDFS concepts ====

  - RDF: Develop the example from XML labs, which describes your faculty:
        * choose which elements from your example are resources and define it using rdf:Description tag
        * add your own namespace to the document and put into it all the properties
        * use a container element to group students from one faculty 
        * after changes validate your example on the page [[http://www.w3.org/RDF/Validator//| RDF Validator from w3.org]] and analyze generated graph
        * turn two of your statements into resources using rdf:Statement tag
  - RDFS Schema: In a new file create RDF Schema class and properties hierarchy:
        * define classes for all existing resources - use rdfs:Class tag
        * with rdf:Property tag create properties for all informations about resources (like _name_of_the_faculty, group_id etc.), define domain and range for each property
  - Linking RDF with RDF Schema
        * save your rdf file from the first exercise as a new file
        * edit the file to use elements from the RDF Schema file from the second exercise
  - Look at prepared graph((example taken from [[http://www.cse.lehigh.edu/~heflin/courses/sw-2008/hw1.pdf|cse homeworks]])) representing some  relations:
     * {{ :pl:dydaktyka:piw:2010:sw:classes_rdf.png?500 }}
     * translate the RDF Graph into the RDF XML syntax
     * check results with [[http://www.w3.org/RDF/Validator//| RDF Validator from w3.org]] or [[http://semweb.salzburgresearch.at/apps/rdf-gravity/download.html|RDF Gravity]]
  - Read about entailment rules in [[http://www.w3.org/TR/rdf-mt/#rules |the RDF Semantics recommendation]], Section 7
     * using the RDFS entailment rules: rdfs2, rdfs3, rdfs5, rdfs7, rdfs9, and rdfs11  determine what triples can be inferred from the example in the previous exercise. 

==== RDFStore ==== 

An RDF store (or triple store) is a system for storing and managing RDF data.
List of tripe stores can be found on the page [[http://semanticweb.org/wiki/Category:RDF_store|SemanticWeb.org]] or in [[http://en.wikipedia.org/wiki/Triplestore|wikipedia.org]]

   - Read about [[http://wiki.dbpedia.org/Datasets| DBPedia data Set]]
   - Browse the DBPedia content starting from one of the listed examples.


===== Komentarze =====

Z braku lepszego miejsca tutaj studenci wpisują komentarze natury ogólnej do tego lab. 8-)