1. MFI Ontology registration Ed2 ~Toward ontology evolution management ~ OKABE, Masao Co-editor ISO/IEC 19763-3 MFI Ontology registration project 2007.12.07

2. 目的外使用・複製禁止 2 Outline 1.What is MFI Ontology registration Ed1? 2.What lacks in MFI Ontology registration Ed1? 3.Evolution management in MFI Ontology registration Ed2 4.Other topics in MFI Ontology registration ED2 5.Overview of proposed Ed2 metamodel 2007/12/07 東京電力・システム企画部・岡部雅夫

3. 目的外使用・複製禁止 3 1.What is MFI Ontology registration Ed1? 2.What lacks in MFI Ontology registration Ed1? 3.Evolution management in MFI Ontology registration Ed2 4.Other topics in MFI Ontology registration Ed2 5.Overview of proposed Ed2 metamodel 2007/12/07 東京電力・システム企画部・岡部雅夫

4. 目的外使用・複製禁止 What is MFI Ontology registration Ed1? ISO/IEC 19763-3 MFI Ontology registration Ed1 is a part of the Metamodel Framework Interoperability standards, and was published as a IS on March 1 st, 2007. Metamodel Framework Interoperability project is multi-part project intending to promote interoperability of metamodels, models and ontologies etc.  Part 1 Reference modelIS  Part 2 Core model FCD  Part 3 Metamodel for ontology registration IS, WD of Ed2 in preparation  Part 4 Metamodel for model mapping CD  Part 5 Metamodel for process models registration WD in preparation  Part 6 Registration procedureStudy Period Participating Counties: Canada, China, Japan, Korea, UK, U.S. Main contributors:China, Japan, Korea 4 2007/12/07 東京電力・システム企画部・岡部雅夫

5. 目的外使用・複製禁止 Features of MFI Ontology registration Features Very simple specifications as a first step  Think big, act samll! Simple and generic structure, irrelevant to languages –Ontology_Whole － Ontology_Component － Ontology_Atomic_Construct Providing a framework to ensure trustiness  Reference Ontology vs. Local Ontology Using a MFI Ontology registration registry, we can at least know what ontologies are there and whether they are trusty or not and get a clue to reuse them. Since it is very simple and generic, MFI Ontology registration only has a little semantics of ontologies, and for their full semantics, it relies on repositories such as OMG ODM. 5 2007/12/07 東京電力・システム企画部・岡部雅夫

6. 目的外使用・複製禁止 6 Simple and generic structure (1 of 4): Common basic structure of ontology Almost any ontology has this simple three granularity structure. An ontology consists of sentences. e.g. Example_Ontology consists of   Buyer   has.Creditrating(Tony)  Buyer(Tony)  Creditrating(Credit-A) A sentence uses symbols. e.g.  Buyer   has.Creditrating(Tony) uses  Buyer  has  logical symbols , ,  (and variables )  Creditrating  Tony Ontology Sentence Symbol 2007/12/07 東京電力・システム企画部・岡部雅夫

7. 目的外使用・複製禁止 7 Simple and generic structure (2 of 3): MFI Ontology registration structure MFI Ontology registration consists of Ontology Whole, Ontology Component, Ontology Atomic Construct that correspond to ontology, sentence, symbol * respectively and that have administrative information ** of its correspondent structural information of this level a reference(URI) to its correspondent, for further semantics, if necessary Note * : Logical symbols such as , ,  and variables are ignored. **: inherited from Administered Item of ISO/IEC 11179-3 MDR, such as registration authority, creation date etc. 2007/12/07 東京電力・システム企画部・岡部雅夫

8. 目的外使用・複製禁止 8 Simple and generic structure (3 of 3): MFI Ontology registration structure e.g. Administrative information etc. corresponding to  Example_Ontology e.g. Administrative information etc. corresponding to each of   Buyer   has.Creditrating(Tony)  Buyer(Tony)  Creditrating(Credit-A) e.g. Administrative information etc. corresponding to of each  Buyer  has  Creditrating  Tony Ontology Whole +administrative info. Ontology Component +administrative info Ontology Atomic Construct +administrative info MFI Ontology registration Actual ontology Ontology Sentence Symbol reference consistOf use reference For actual ontologies, MFI Ontology registration mainly relies on OMG ODM 2007/12/07 東京電力・システム企画部・岡部雅夫

9. 目的外使用・複製禁止 9 Providing a framework to ensure trustiness Reference Ontology vs. Local Ontology Reference Ontology Standardized ontology that is usable and sharable by a community of interest Trustworthy to others A reference ontology consists of sentences only in reference ontologies. A sentence in a reference ontology uses symbols only in reference ontologies. Local Ontology Localized ontology for some applications based on Reference Ontologies It is its user’s responsibility to trust this ontology or not. A local ontology consists of sentences both in this local ontology and other reference ontologies. A sentence in a local ontology uses a symbols in this local ontology and other reference ontologies. 2007/12/07 東京電力・システム企画部・岡部雅夫

10. 目的外使用・複製禁止 10 Core portion of MFI Ontology registration metamodel Reference Ontology Whole Reference Ontology Component Reference Ontology Atomic Construct Local Ontology Whole 0:* 0:1 Local Ontology Component Local Ontology Atomic Construct 0:1 0:* sameAs 2007/12/07 東京電力・システム企画部・岡部雅夫

11. 目的外使用・複製禁止 11 Example1 (1 of 2) Suppose that ontology A consists of sentence RC1, RC2 and RC3 as follows; 11 RC1 RC2 RC3 2007/12/07 東京電力・システム企画部・岡部雅夫

12. 目的外使用・複製禁止 12 Example1 (2 of 2) Note OWL constructs such as “ObjectProperty”, “subClassOf” etc. have no effects. 12 A URI Administered Info. RC1 NamespaceURI Administered Info. RC2 NamespaceURI Administered Info. RC3 NamespaceURI Administered Info. KernelUnit NamespaceURI Administered Info. dimensionality NamespaceURI Administered Info. Dimensionality NamespaceURI Administered Info. Unit NamespaceURI Administered Info. metre NamespaceURI Administered Info. length NamespaceURI Administered Info. Ontology Whole Ontology Component Ontology Atomic Construct Metadata registered in MFI Ontology registration 2007/12/07 東京電力・システム企画部・岡部雅夫

13. 目的外使用・複製禁止 13 1.What is MFI Ontology registration Ed1? 2.What lacks in MFI Ontology registration Ed1? 3.Evolution management in MFI Ontology registration Ed2 4.Other topics in MFI Ontology registration Ed2 5.Overview of proposed Ed2 metamodel 2007/12/07 東京電力・システム企画部・岡部雅夫

14. 目的外使用・複製禁止 14 Nature of ontologies By nature, ontologies are reused mutually and ontologies evolve gradually as they capture more semantics. 2007/12/07 東京電力・システム企画部・岡部雅夫

15. 目的外使用・複製禁止 15 Example2 First, ontology B uses ontology A. Second, ontology A evolves from ver.1 to ver.2. But ontology B still uses ontology A ver.1. Third, ontology C uses ontology A ver.2. Note:This kind of situation often happens. ontology B ontology A use ontology B use ontology A Ver.2 Ver.1 evolves ontology B use ontology A Ver.2 Ver.1 evolves ontology C use 2007/12/07 東京電力・システム企画部・岡部雅夫

16. 目的外使用・複製禁止 16 Problem of MFI Ontology registration Ed1 MFI Ontology registration needs to support facilities to manage multi-versions of an ontology and to manage how an ontology evolves. However, MFI Ontology registration Ed1 does not have such facilities. 2007/12/07 東京電力・システム企画部・岡部雅夫

17. 目的外使用・複製禁止 17 Example1 (1 of 4) :roughly speaking Suppose that ontology A evolves as follows; 17 RC2 RC1 RC2 RC3 evolves Note: “subClassOf “and “disjointWith” are very different semantically. 2007/12/07 東京電力・システム企画部・岡部雅夫

18. 目的外使用・複製禁止 18 Example1 (2 of 4) :roughly speaking Although RC2 evolves substantially, there is no change in MFI Ontology registration Ed1 except (Namespace)URI and some Adminitered Information since “subClassOf” and “disjointWith” have no effect to MFI Ontology registration. 18 A URI Administered Info. RC1 NamespaceURI Administered Info. RC2 NamespaceURI Administered Info. RC3 NamespaceURI Administered Info. KernelUnit NamespaceURI Administered Info. dimensionality NamespaceURI Administered Info. Dimensionality NamespaceURI Administered Info. Unit NamespaceURI Administered Info. metre NamespaceURI Administered Info. length NamespaceURI Administered Info. Ontology Whole Ontology Component Ontology Atomic Construct 2007/12/07 東京電力・システム企画部・岡部雅夫

19. 目的外使用・複製禁止 19 Example1 (3 of 4): more precisely speaking Fortunately or unfortunately, usually, different versions of an ontology are identified by different URIs. For example,  The current version of famous OWL Wine ontology is identified by http://www.w3. org /TR/2003/PR-owl-guide- 20031209/wine, which is also xmlns and xml:base.http://www.w3. org /TR/2003/PR-owl-guide- 20031209/wine  The prior version is identified by http://www.w3.org/TR/2003/CR-owl-guide-20030818/wine, which is also xmlns and xml:base.http://www.w3.org/TR/2003/CR-owl-guide-20030818/wine  So, in the current version, “wine” is http://www.w3.org/TR/2003/PR-owl-guide-20031209/wine#wine but, in the prior version, it is http://www.w3.org/TR/2003/CR-owl-guide-20030818/wine#wine and they are different. Then, in MFI Ontology registration registry, every component and atomic constructs of the current version and of the prior version are regarded as different since they are identified by NamespaceURI-prefixed name. 2007/12/07 東京電力・システム企画部・岡部雅夫

20. 目的外使用・複製禁止 20 Example1 (4 of 4) : more precisely speaking In MFI Ontology registration, ontology A ver.1 and ontology A ver.2 are treated as comletely different since their (Namespace)URIs are different, although they are practically same except RC2 are substantially different. 20 A URI _1 Admin. Info. RC1 NsURI_ 1 Admin. Info. RC2 NsURI_ 1 Admin. Info. RC3 NsURI_ 1 Admin. Info. KernelUnit NsURI_ 1 Admin. Info. dimensionality NsURI_ 1 Admin. Info. Dimensionality NsURI_ 1 Admin. Info. Unit NsURI_ 1 Admin. Info. metre NsURI_ 1 Admin. Info. length NsURI_ 1 Admin. Info. Unit NsURI_ 2 Admin. Info. A URI _2 Admin. Info. RC1 NsURI_ 2 Admin. Info. RC2 NsURI_ 2 Admin. Info. RC3 NsURI_ 2 Admin. Info. KernelUnit NsURI_ 2 Admin. Info. dimensionality NsURI_ 2 Admin. Info. Dimensionality NsURI_ 2 Admin. Info. metre NsURI_ 2 Admin. Info. length NsURI_ 2 Admin. Info. completely different 2007/12/07 東京電力・システム企画部・岡部雅夫

21. 目的外使用・複製禁止 21 Example2 In the case that ontology B uses ontology A ver.1 and that ontology C uses ontology A ver.2 What MFI Ontology registration can recognize is In MFI Ontology registration Ed1, the fact that “ontology B uses ontology A ver.1” is represented as “an ontology_whole of ontology B consists of ontology_components of ontology A ver.1”. But, ontology A ver.1 and ontology A ver.2 are different ontologies and not different versions of the same ontology. and not ontology B use ontology A ver.2 ver.1 evolves ontology C use ontology B use ontology A ver.1 ontology C use ontology A ver.2 2007/12/07 東京電力・システム企画部・岡部雅夫

22. 目的外使用・複製禁止 22 1.What is MFI Ontology registration Ed1? 2.What lacks in MFI Ontology registration Ed1? 3.Evolution management in MFI Ontology registration Ed2 4.Other topics in MFI Ontology registration 5.Overview of proposed Ed2 metamodel 2007/12/07 東京電力・システム企画部・岡部雅夫

23. 目的外使用・複製禁止 What is MFI Ontology registration Ed2? MFI Ontology registration Ed2 supports facilities to manage multi-versions of an ontology and to manage how an ontology evolves, since ontologies are reused mutually and ontologies evolve gradually as they capture more semantics by nature. 23 2007/12/07 東京電力・システム企画部・岡部雅夫

24. 目的外使用・複製禁止 24 Overview: example1 24 A URI _1 Admin. Info. RC1 NsURI_ 1 Admin. Info. RC2 NsURI_ 1 Admin. Info. RC3 NsURI_ 1 Admin. Info. KernelUnit NsURI_ 1 Admin. Info. dimensionality NsURI_ 1 Admin. Info. Dimensionality NsURI_ 1 Admin. Info. Unit NsURI_ 1 Admin. Info. metre NsURI_ 1 Admin. Info. length NsURI_ 1 Admin. Info. Unit NsURI_ 2 Admin. Info. A URI _2 Admin. Info. RC1 NsURI_ 2 Admin. Info. RC2 NsURI_ 2 Admin. Info. RC3 NsURI_ 2 Admin. Info. KernelUnit NsURI_ 2 Admin. Info. dimensionality NsURI_ 2 Admin. Info. Dimensionality NsURI_ 2 Admin. Info. metre NsURI_ 2 Admin. Info. length NsURI_ 2 Admin. Info.  evolves  same  corresponds to  evolves from ver.1 to ver.2  Some other metadata such as backward compatibility etc.  same 2007/12/07 東京電力・システム企画部・岡部雅夫

25. 目的外使用・複製禁止 Three cases There are three cases that an ontology evolves outside MFI Ontology registration registry. Case1  Different URIs for each version of an ontology and different URIs for each version of names in an otology Case2  Different URIs for each version of an ontology, but mostly the same URIs for each version of names in an ontology  This is a typical case. Case3  Same URI for each version of an ontology.  Usually, this is the case that Persistent URLs are used. e.g. http://purl.org/dc/elements/1.1/http://purl.org/dc/elements/1.1/ Since MFI Ontology registration is so generic, it should support all of them. 25 2007/12/07 東京電力・システム企画部・岡部雅夫

26. 目的外使用・複製禁止 Case1 (1 of 2) Different URIs for each version of an ontology and different URIs for each version of symbols in an otology This is the case shown as the example1 in Overview (at slide 24) etc. It is not easy to decide whether the corresponding symbols have the same semantics or not. 26 2007/12/07 東京電力・システム企画部・岡部雅夫

27. 目的外使用・複製禁止 Case1 (2 of 2) For example, concerning “KernelUnit”  Probably, many people say “KernelUnit in ver.1 and in ver.2 have different semantics because in ver.1, KernelUnit is a subclass of Unit but in ver.2, KernelUnit is disjoint with Unit. Then, how about Unit?  Some people may say “Unit in ver.1 and in ver2 have different semantics because in ver.1 Unit has KernelUnit as a subclass, but not in ver.2”.  But, others may say “No. That difference is not about Unit but about KernelUnit.” How about metre?  Some people may say “Metre in ver.1 and in ver.2 have different semantics because in ver.1, metre is an instance of Unit, but not in ver. 2”.  But, probably many say “No. They are the same” 27 2007/12/07 東京電力・システム企画部・岡部雅夫

28. 目的外使用・複製禁止 Case 2 (1 of 2) Different URIs for each version of an ontology, but mostly the same URIs for each version of names in an ontology See example3 at next slide. In this case, Unit, KernelUnit and metre are identical in ver.1 and ver.2 as symbols since they have the same NsURI_1 both in ver.1 and ver.2. However, it is still not easy to decide whether they have the same semantics in ver.1 and ver.2. 28 2007/12/07 東京電力・システム企画部・岡部雅夫

29. 目的外使用・複製禁止 29 Case2 (2 of 2): example 3 29 A URI _1 Admin. Info. RC1 NsURI_ 1 Admin. Info. RC2 NsURI_ 1 Admin. Info. RC3 NsURI_ 1 Admin. Info. KernelUnit NsURI_ 1 Admin. Info. dimensionality NsURI_ 1 Admin. Info. Dimensionality NsURI_ 1 Admin. Info. Unit NsURI_ 1 Admin. Info. metre NsURI_ 1 Admin. Info. length NsURI_ 1 Admin. Info. A URI _2 Admin. Info. RC1 NsURI_ 2 Admin. Info. RC2 NsURI_ 2 Admin. Info. RC3 NsURI_ 2 Admin. Info.  evolves  evolves from ver.1 to ver.2  Some other metadata such as backward compatibility etc.  same 2007/12/07 東京電力・システム企画部・岡部雅夫

30. 目的外使用・複製禁止 Case3 Same URI for each version of an ontology This is a case that an ontology is just updated and mulch-versions cannot be supported. MFI Ontology registration can at least update the administered information such as “version”, “effective date” etc. 30 2007/12/07 東京電力・システム企画部・岡部雅夫

31. 目的外使用・複製禁止 31 Issues to be resolved Whether fork-type evolution is acceptable or not? Maybe, for local ontologies, yes, but for reference ontologies, no, since reference ontologies should be standardized. Whether a new version may have the same URI as its prior version? If always only the latest version is necessary, it is fine.  Actually, Persistent URLs are very convenient. But, if multi-versions are necessary, it is not advisable (i.e. Case 3). Exact metadata (references and attributes) that MFI Ontology registration metamodel shall have. China is extensively studying them. 31 ver.1 ver.2ver.3 ver.4ver.5 fork-type evolution 2007/12/07 東京電力・システム企画部・岡部雅夫

32. 目的外使用・複製禁止 32 1.What is MFI Ontology registration Ed1? 2.What lacks in MFI Ontology registration Ed1? 3.Evolution management in MFI Ontology registration Ed2 4.Other topics in MFI Ontology registration Ed2 5.Overview of proposed Ed2 metamodel 2007/12/07 東京電力・システム企画部・岡部雅夫

33. 目的外使用・複製禁止 1)Relation between reference and local ontology will be expanded. Motivation (1 of 2) The relation between reference ontology and local ontology in MFI Ontology registration Ed1 needs to be expanded to a partial-ordered relation. MFI Ontology registration Ed1 defines Reference Ontology and Local Ontology as follows;  Reference Ontology –ontology that is usable and sharable by a community of interest  Local Ontology –ontology that is specialized for defined applications and based on at least one reference ontology puts the following constraints on local ontology.  A local_ontology_component shall be consisted of by exactly one local_ontology_whole and not by a reference_ontology_whole since it is localized.  A local_ontology_atomic_construct shall be used by exactly one local_ontology_component and not by a reference_ontology_component since it is localized. 33 2007/12/07 東京電力・システム企画部・岡部雅夫

34. 目的外使用・複製禁止 34 1)Relation between reference and local ontology will be expanded. Motivation (2 of 2) By nature, however, ontologies are reused mutually. Even local ontologies should be able to reused by other local ontologies in some extent. MFI Ontology registration Ed2 will introduce a partial order relation among local ontologies to control the extent that local ontologies can be reused by other local ontologies. 34 2007/12/07 東京電力・システム企画部・岡部雅夫

35. 目的外使用・複製禁止 A partial ordered set “Reusable Level” MFI Ontology registration Ed2 will introduce a partial ordered set called “Reusable Level”. There is an element R  “Reusable Level” For any element e  “Reusable Level”, e  R Example 35 R L1 L2 L5 L4 L3 1)Relation between reference and local ontology will be expanded 2007/12/07 東京電力・システム企画部・岡部雅夫

36. 目的外使用・複製禁止 A reference “reusability” Ontology Whole, Ontology Component and Ontology Atomic Construct will have a reference called “reusability” to “Reusable Level” with its multiplicity 1:1. Ontolgy Whole O has R as reusability iff O is a reference ontology. Ontology Component C has R as reusability iff C is a reference ontology component. Ontology Atomic Construct A has R as reusability iff A is a reference ontology atomic construct. 36 1)Relation between reference and local ontology will be expanded 2007/12/07 東京電力・システム企画部・岡部雅夫

37. 目的外使用・複製禁止 Extended constraints for reusability Extended constraints in ED2 A local_ontology_component with reusability Ln can be consisted of by an ontology_whole with reusability Lm iff Lm  Ln. A local_ontology_atomic_construct with reusability Ln can be used by a local_ontology_component with reusability Lm iff Lm  Ln. Note: This is a natural extension of the following constraints in Ed1.  A local_ontology_component shall be consisted of by exactly one local_ontology_whole and not by a reference_ontology_whole.  A local_ontology_atomic_construct shall be used by exactly one local_ontology_component and not by a reference_ontology_component. 37 1)Relation between reference and local ontology will be expanded 2007/12/07 東京電力・システム企画部・岡部雅夫

38. 目的外使用・複製禁止 Example A reference ontology component can be reused by any ontology component since reference ontology component has maximum reusability R. 38 L3 R L1 L2 L5 L4 A local ontology atomic construct with reusability L1 can be reused by a local ontology component with reusability L1, L3 or L4 and not with R, L2 or L5. A local ontology atomic construct with reusability L2 can be reused by a local ontology component with reusability L2, L3, L4 or L5 and not with R or L1. 1)Relation between reference and local ontology will be expanded 2007/12/07 東京電力・システム企画部・岡部雅夫

39. 目的外使用・複製禁止 2) Ed2 will support ontology inclusion. (1 of 2) Ed1 does not support ontology inclusion such as “owl:import”. So, in the case of Ed1 simply registers ontology A as follows, expanding “import”. 2007/12/07 東京電力・システム企画部・岡部雅夫 39 A C-A1 C-A2 A-A1A-A2 A-A3 B C-B1 C-B2 A-B1 A-B2 imports ontology sentence symbol ontology whole ontology component ontology atomic construct A C-A1 C-A2 A-A1 A-A2 A-A3 C-B1C-B2 A-B1A-B2

40. 目的外使用・複製禁止 2) Ed2 will support ontology inclusion. (2 of 2) But, Ed1 has a problem in the case that ontology B is not registered because in that case ontology A cannot expand ontology B. So, Ed2 will simply register ontology A as it is as follows, Note: Since ontology B is not registered, the information on the ontology component and ontology atomic construct of ontology B cannot be gained, but a part of the information on the ontology whole of ontology B can be gained from ontology A. ontology whole ontology component ontology atomic construct A C-A1 C-A2 A-A1A-A2 A-A3 B imports

41. 目的外使用・複製禁止 3) Ed2 will use IRIs, rather than URIs. To support non-European characters, including Hungul, Chinese and Japanese character, MFI Ontology registration Ed2 will use IRIs, rather than URIs. IRI : RFC 3987 Internationalized Resource Identifiers (IRIs), IETF Proposed Standard 2007/12/07 東京電力・システム企画部・岡部雅夫 41

42. 目的外使用・複製禁止 42 1.What is MFI Ontology registration Ed1? 2.What lacks in MFI Ontology registration Ed1? 3.Evolution management in MFI Ontology registration Ed2 4.Other topics in MFI Ontology registration Ed2 5.Overview of proposed Ed2 metamodel 2007/12/07 東京電力・システム企画部・岡部雅夫

43. 目的外使用・複製禁止 Overview of proposed Ed2 metamodel Evolution and reusability view only if reusability of an ontology component is lessThanOrEqual to reusability of an ontology atomic construct. 2007/12/07 東京電力・システム企画部・岡部雅夫 43 Ontology Whole Ontology Component Ontology Atomic Construct sameAs evolvesTo correspondsTo only if reusability of an ontology whole is lessThanOrEqual to reusability of an ontology component. reusability lessThanOrEqual Reusable Level imports

44. 目的外使用・複製禁止 Overview of proposed Ed2 metamodel Reference and Local Ontology view only if reusability of an ontology component is lessThanOrEqual to reusability of an ontology atomic construct. 0:* 0:1 0:* sameAs only if reusability of an ontology whole is lessThanOrEqual to reusability of an ontology component. evolvesTo correspondsTo 0:1 0:* 0:1 evolvesTo 0:1 0:* evolvesTo correspondsTo evolvesTo 0:1 evolvesTo 0:1 evolvesTo 0:1 Local Ontology Whole Local Ontology Component Local Ontology Atomic Construct Reference Ontology Atomic Construct Reference Ontology Component Reference Ontology Whole 2007/12/07 東京電力・システム企画部・岡部雅夫 44 Note: The associations “imports” are omitted just for simplicity

45. 目的外使用・複製禁止 Thank you for your attention. MFI Ontology registration Ed2 WD is in preparation. Any comments and/or contributions are very welcome to okabe.masao tepco.co.jp. 2007/12/07 東京電力・システム企画部・岡部雅夫 45