Presentation on N3 for Semantic Web.

1. Notation 3(N 3)
Presented By
Yogendra Tamang
070-MSCS-670

2. Outline
• Introduction
• Square Brackets
• Sharing Concepts
• Making Vocabularies
• Equivalence
• Publishing
• References

3. Introduction
• RDF just collection of objects in subject, verb and object form
• Everything represented by URI
• Object may be literal
• More readable
<#Ram> <#Knows> <#Sita>
<#Ram> <#age> 25.
<#pat> has <#child> <#jo>.
<#jo> is <#child> of <#pat>.

4. Introduction
• Several statements about same subjects
Semicolon (;) : describing property of same subject.
Comma(,) : Another object with same predicate and subject.
<#pat> <#child> <#al>, <#chez>, <#jo>;
<#age> 24;
<#eyecolor> “blue”.

5. Example:
Age Eye Color
Ram 24 blue
Hari 28 green
Shyam 6 green
<#Hari> <#age> 24;<#eyecolor> “blue”.
<#Ram> <#age> 28;<#eyecolor> “green”.
<#Ram> <#age> 6;<#eyecolor> “green”.

6. Square Braces [ ]
• Something exists with given properties but don't give you a way to
refer to it elsewhere in this or another document
• Example
<#pat> <#child> [<#age> 4, <#age> 3].

7. Square Braces []
• Futher
[<#name> “Ram"; <#age> 24; <#eyecolor> "blue" ].
[<#name> “Hari" ; <#age> 28; <#eyecolor> "green" ].
[<#name> “Shyam" ; <#age> 6; <#eyecolor> "green" ].

8. Sharing concepts
• Semantic Web Can not define in one document what something means.
• Uses URI for concepts
<> <#title> “Semantic Web Introduction”.
• N3 allows a shorthand prefix for long part namespace
• <>< http://purl.org/dc/element/1.1/title > “Semantic Web
Introduction”
@prefix dc: <http://purl.org/dc/element/1.1>
<> dc:title “Semantic Web Introduction”

9. Conventions on using prefix
• Use colon and dc and titile
• No angular brackets
• Prefix can be used for rest of file
Well known namespaces
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .

10. Writing Data
• @prefix: <#>  Document itself
:pat :child [:age 4], [:age 3].

11. Making Vocabularies
• Define new classes of things and new properties
• What type of thing is X ???
• Answer: X belongs to “ClassName”
• Property what type of something is ? Rdf:type  a
** Define a class “Person”
:Person a rdfs:class.
** Create a object of class Person
:pat a :Person.

12. Making Vocabularies
• An object may be of many classes
• Example
:Woman a rdfs:Class; rdfs:SubClassOf :Person.
• Property declares relationship between two things
• Example
:sister a rdf:Property

13. Domain and Range
• When subject of property must be in a class, that class is domain of
the property
• When object must be in a class that class is range of property
:sister rdfs:domain :Person;
rdfs:range :Woman.
Class identifiers start with capitals and properties small letters

14. Equivalence
• One or more terms in one vocabulary may be same in another
vocabulary
• Very Useful
:Woman=foo:FemaleAdult
:Title a rdf:Property;=dc:title.
• Interchange of Data

15. Choosing Namespace and Publishing your
Vocabulary
• RDF Schema and OWL Vocabularies  Machine Readable
• Create URI as vocabulary terms that work on browsers
ex: http://example.com/terms
• Publish on server and portion of URI space of organization that
commit to maintain on future too..

16. Shorthand for common predicates
a <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
= <http://www.w3.org/2002/07/owl#sameAs>
=> <http://www.w3.org/2000/10/swap/log#implies>
<= <http://www.w3.org/2000/10/swap/log#implies> but in the inverse direction

17. Example
• There is person, Pat, known as "Pat Smith" and "Patrick Smith". Pat
has a pet dog named "Rover".
@prefix : <http://www.w3.org/2000/10/swap/test/demo1/about-pat#> .
@prefix bio: <http://www.w3.org/2000/10/swap/test/demo1/biology#> .
@prefix per: <http://www.w3.org/2000/10/swap/test/demo1/friends-vocab#>.
:pat a bio:Human;
per:name "Pat Smith", "Patrick Smith";
per:pet [
a bio:Dog; per:name "Rover"
] .

18. Directed Labeled Graph

19. References
• http://www.w3.org/2000/10/swap/doc/
• http://www.csee.umbc.edu/courses/graduate/691/spring13/01/pape
rs/n3logic-tplp.pdf
• http://www.w3.org/2000/10/swap/doc/cwm.html
• http://www.w3.org/TeamSubmission/2011/SUBM-n3-20110328/