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Expressing Classification Schemes  with OWL 2 Web Ontology Language
Considering basic  functional requirements  Can be done with  many languages,  e.g., SKOS, RDFs, OWL ISKO-2010, Rome ©ZengPanzerSalaba
3. WHEN OWL MEETS CLASSIFICATION ,[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
Our interests in OWL ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],OWL supports various ways of describing classes  ISKO-2010, Rome ©ZengPanzerSalaba
[object Object],[object Object],[object Object],[object Object],3.1  OWL for  complex class expressions ISKO-2010, Rome ©ZengPanzerSalaba
Complex class expressions are needed  for  synthesized classes  ISKO-2010, Rome ©ZengPanzerSalaba  ,[object Object],[object Object],[object Object],Auxiliary tables rules combine add Subject schedule A Subject schedule B 1 2 2 follow 3 To accommodate new subjects and reflect the nature of interdisciplinary, instructions are provided to the classifier to  construct  a number in practice:
[object Object],[object Object],[object Object],821.008 Collections of English poetry is built with  82   (following the instruction at  820.1-828 Subdivisions of English literature )  plus  100  (following the instruction at  T3B--1001-T3B--1009 Standard subdivisions; collections; history, description, critical appraisal )  plus  8  Collections of literary texts  from the add table at  T3B--1-T3B--8 Specific forms .   821   English poetry   821.008   English poetry--collections   821.00803543   Love--poetry--English literature--collections, . . .   821.0080355   English poetry--social themes--collections, . . .   821.008036   English poetry--nature--collections, . . .   821.0080382   English poetry--religious themes--collections, . . .   821.00 9    English poetry--history and criticism   821.04   English poetry--lyric poetry, . . .   821.0708   Humorous poetry--English literature--collections, . . .   http://ddc.typepad.com/025431/ddc_tip_of_the_week/ Source:  One Zero or Two?  Dewey Blog. September 28, 2006 ISKO-2010, Rome ©ZengPanzerSalaba  rules
  The  intersection  of two classes  ISKO-2010, Rome ©ZengPanzerSalaba
ObjectIntersectionOf ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
The  union  of two classes ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
 “ including” “class here”  “class elsewhere” Example from DDC  025.04 Information Storage and Retrieval Systems ISKO-2010, Rome ©ZengPanzerSalaba
The  complement  of a class ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
Review: Our interests in OWL ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
3.2  AXIOMs for relationships between class expressions ,[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
Overview: The Class Axioms of OWL 2  http://www.w3.org/TR/owl2-syntax/#Inverse_Object_Properties ISKO-2010, Rome ©ZengPanzerSalaba
SubClassOf axiom  ,[object Object],Subclass axioms are a fundamental type of axioms in OWL 2 and can be used to construct a class hierarchy.  ISKO-2010, Rome ©ZengPanzerSalaba
DisjointClasses axiom ,[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
EquivalentClasses axiom  ,[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
EquivalentClasses axiom for Alternative Classes However this is not enough.  There are also certain relationship types and constrains between the classes. EquivalentClasses ( :X17 : Q89) ISKO-2010, Rome ©ZengPanzerSalaba  [ ] [Q89 Environmental Biology] Preferred class:  X17 Example from Chinese Library Classification (CLC): X17   Environmental Biology …… ……
Review: Our interests in OWL ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
3.3  Properties and restrictions  for more complicated class expressions and relationships  ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
1)  Symmetric  Object Property [Q89 Environmental Biology] Preferred class:  X17 CLC’s alternative classes  X17  Environmental Biology …… …… EquivalentClasses (  :X17 S ymmertricbjectProperty  ( :isAlternativeClass  : Q89) ) ISKO-2010, Rome ©ZengPanzerSalaba  [ ]
2)  Inverse  object properties  ,[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
3)  Restrictions ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Quantifier Restrictions ( Existential ∃ , Universal ∀) Cardinality Restrictions (Min ≥, Equal =, Max ≤) Has Value Restriction (∍) ,[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba
Restrictions  can be applied to deal with class–topic relationships 370.113 Vocational education Class here  career education ,  occupational training ,  vocational schools Class  on-the-job training ,  vocational training provided by industry  in  331.2592 For  vocational education at secondary level , see  373.246 ; for  adult vocational education , see  374.013 Topical neighborhood shaped by (among other things): Caption Class-here note Inclusion of topics Exclusion of topics Class-elsewhere note See reference ISKO-2010, Rome ©ZengPanzerSalaba
Class description example ISKO-2010, Rome ©ZengPanzerSalaba
Inferred class neighborhood ISKO-2010, Rome ©ZengPanzerSalaba
Summary: Our interests in  Expressing Classification Schemes with OWL ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],ISKO-2010, Rome ©ZengPanzerSalaba

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Expressing Classification Schemes -- Part 3

  • 1. Expressing Classification Schemes with OWL 2 Web Ontology Language
  • 2. Considering basic functional requirements Can be done with many languages, e.g., SKOS, RDFs, OWL ISKO-2010, Rome ©ZengPanzerSalaba
  • 3.
  • 4.
  • 5.
  • 6.
  • 7.
  • 8.
  • 9. The intersection of two classes ISKO-2010, Rome ©ZengPanzerSalaba
  • 10.
  • 11.
  • 12. “ including” “class here” “class elsewhere” Example from DDC 025.04 Information Storage and Retrieval Systems ISKO-2010, Rome ©ZengPanzerSalaba
  • 13.
  • 14.
  • 15.
  • 16. Overview: The Class Axioms of OWL 2 http://www.w3.org/TR/owl2-syntax/#Inverse_Object_Properties ISKO-2010, Rome ©ZengPanzerSalaba
  • 17.
  • 18.
  • 19.
  • 20. EquivalentClasses axiom for Alternative Classes However this is not enough. There are also certain relationship types and constrains between the classes. EquivalentClasses ( :X17 : Q89) ISKO-2010, Rome ©ZengPanzerSalaba [ ] [Q89 Environmental Biology] Preferred class: X17 Example from Chinese Library Classification (CLC): X17 Environmental Biology …… ……
  • 21.
  • 22.
  • 23. 1) Symmetric Object Property [Q89 Environmental Biology] Preferred class: X17 CLC’s alternative classes X17 Environmental Biology …… …… EquivalentClasses ( :X17 S ymmertricbjectProperty ( :isAlternativeClass : Q89) ) ISKO-2010, Rome ©ZengPanzerSalaba [ ]
  • 24.
  • 25.
  • 26.
  • 27. Restrictions can be applied to deal with class–topic relationships 370.113 Vocational education Class here career education , occupational training , vocational schools Class on-the-job training , vocational training provided by industry in 331.2592 For vocational education at secondary level , see 373.246 ; for adult vocational education , see 374.013 Topical neighborhood shaped by (among other things): Caption Class-here note Inclusion of topics Exclusion of topics Class-elsewhere note See reference ISKO-2010, Rome ©ZengPanzerSalaba
  • 28. Class description example ISKO-2010, Rome ©ZengPanzerSalaba
  • 29. Inferred class neighborhood ISKO-2010, Rome ©ZengPanzerSalaba
  • 30.

Editor's Notes

  1. http://www.leda-tutorial.org/en/official/ch02s08s02.html
  2. Presenting notation-building rules. Each classification implements certain rules for building notations. The following are some typical examples. 1) In current authority systems there are always records indicating how a notation should be composed or de-composed. 2) A synthesized number can be constructed by adding or appending numbers from a table or from other parts of the schedule. Instructions are provided to the classifier to construct a classification number by adding numbers from other parts of the schedule, from a table, or by basing it on a pattern defined in another part of the schedule. 3) Depending on the degree of synthesized components, some classification schemes have a variety of faceted structures for their main schedules, sub-schedules, or individual classes. Rules and instruction guidance are always included in such cases. 4) There could be full, abridged, and extended (+) notations for the derivations from a general classification system. Unlike a thesaurus, a classification system usually develops variations of a scheme with different scales. Implementers decide to which degree they want to implement it in practice. For example, in CLC's ‘062.32+6’ the number after ‘+’ is the optional, extended number with higher specificity.
  3. The intersection of two classes consists of exactly those individuals which are instances of both classes. The following example states that the class Mother consists of exactly those objects which are instances of both Woman and Parent: EquivalentClasses(   :Mother ObjectIntersectionOf( :Woman :Parent ) ) In Functional-Style Syntax
  4. General works on cardiac rehabilitation are classed in 616.1203 Heart diseases—rehabilitation (built with 616.12 Diseases of heart plus 03 Rehabilitation from the add table under 616.1–616.9 Specific diseases , following the add footnote at 616.12 : “Add as instructed under 616.1–616.9”).  Examples of works classed in 616.1203 are Cardiac Rehabilitation: A Guide to Practice in the 21st Century and Cardiac Rehabilitation . http://ddc.typepad.com/025431/600699_technology/ Number Building: The process of constructing a number by adding notation from the tables or other parts of the schedules to a base number Add note A note instructing the classifier to append digits found elsewhere in the DDC to a given base number. In Functional-Style Syntax
  5. Image credit: http://thesemanticway.files.wordpress.com/2008/11/geography_ontology2.png
  6. Restrictions describe a class of individuals based on the type and possibly number of relationships that they participate in. - Restrictions can be grouped into three main categories: Quantifier Restrictions ( Existential ∃ , Universal ∀) - Cardinality Restrictions (Min ≥, Equal =, Max ≤) Has Value Restriction (∍) These symbols are from descriptive logic. We will not get into these, but will have an example of existential restriction.