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MFI Ontology registration Ed2 ~Toward ontology evolution management ~

Explore the evolution management and other topics in MFI Ontology Registration, a project focused on promoting interoperability of metamodels, models, and ontologies. Learn about the simple and generic structure of ontology registration and how it provides a framework to ensure trustworthiness.

matthewconner
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MFI Ontology registration Ed2 ~Toward ontology evolution management ~

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  1. MFI Ontology registrationEd2 ~Toward ontology evolution management ~ OKABE, Masao Co-editor ISO/IEC 19763-3 MFI Ontology registration project 2007.12.07

  2. Outline What is MFI Ontology registration Ed1? What lacks in MFI Ontology registration Ed1? Evolution management in MFI Ontology registrationEd2 Other topics in MFI Ontology registration ED2 Overview of proposed Ed2 metamodel 東京電力・システム企画部・岡部雅夫 2007/12/07

  3. What is MFI Ontology registration Ed1? What lacks in MFI Ontology registration Ed1? Evolution management in MFI Ontology registration Ed2 Other topics in MFI Ontology registration Ed2 Overview of proposed Ed2 metamodel 東京電力・システム企画部・岡部雅夫 2007/12/07

  4. 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 1st, 2007. • Metamodel Framework Interoperability project • is multi-part project intending to promote interoperability of metamodels, models and ontologies etc. • Part 1 Reference model IS • 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 procedure Study Period • Participating Counties: Canada, China, Japan, Korea, UK, U.S. • Main contributors: China, Japan, Korea 東京電力・システム企画部・岡部雅夫 2007/12/07

  5. 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. 東京電力・システム企画部・岡部雅夫 2007/12/07

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

  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. 東京電力・システム企画部・岡部雅夫 2007/12/07

  8. Actual ontology MFI Ontology registration • 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 Ontology Whole +administrative info. Ontology reference consistOf Ontology Component +administrative info Sentence reference use Ontology Atomic Construct +administrative info Symbol reference • Creditrating • Tony Simple and generic structure (3 of 3):MFI Ontology registration structure • For actual ontologies, MFI Ontology registration mainly relies on OMG ODM 東京電力・システム企画部・岡部雅夫 2007/12/07

  9. Providing a framework to ensure trustinessReference 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. 東京電力・システム企画部・岡部雅夫 2007/12/07

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

  11. Example1 (1 of 2) Suppose that ontology A consists of sentence RC1, RC2 and RC3 as follows; <owl:ObjectProperty rdf:ID="dimensionality"> <rdfs:domain rdf:resource="#Unit" /> <rdfs:range rdf:resource="#Dimensionality" /> </owl:ObjectProperty> <owl:Class rdf:ID="KernelUnit"> <rdfs:subClassOf rdf:resource="#Unit"/> </owl:Class> <KernelUnit rdf:ID="metre"> <dimensionality> <Dimensionality rdf:ID="length"/> </dimensionality> </KernelUnit> RC1 RC2 RC3 11 東京電力・システム企画部・岡部雅夫 2007/12/07

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

  13. What is MFI Ontology registration Ed1? What lacks in MFI Ontology registration Ed1? Evolution management in MFI Ontology registration Ed2 Other topicsin MFI Ontology registration Ed2 Overview of proposed Ed2 metamodel 東京電力・システム企画部・岡部雅夫 2007/12/07

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

  15. use ontology A ontology B 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 A use ontology B Ver.1 Ver.2 evolves ontology A use use ontology B ontology C Ver.1 Ver.2 evolves 15 東京電力・システム企画部・岡部雅夫 2007/12/07

  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. 東京電力・システム企画部・岡部雅夫 2007/12/07

  17. Example1 (1 of 4) :roughly speaking Suppose that ontology A evolves as follows; RC1 <owl:ObjectProperty rdf:ID="dimensionality"> <rdfs:domain rdf:resource="#Unit" /> <rdfs:range rdf:resource="#Dimensionality" /> </owl:ObjectProperty> RC2 <owl:Class rdf:ID="KernelUnit"> <rdfs:subClassOf rdf:resource="#Unit"/> </owl:Class> RC3 <KernelUnit rdf:ID="metre"> <dimensionality> <Dimensionality rdf:ID="length"/> </dimensionality> </KernelUnit> RC2 <owl:Class rdf:ID="KernelUnit"> <owl:disjointWith rdf:resource="#Unit/> </owl:Class> evolves Note: “subClassOf “and “disjointWith” are very different semantically. 17 東京電力・システム企画部・岡部雅夫 2007/12/07

  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. A URI Administered Info. Ontology Whole RC2 NamespaceURI Administered Info. RC1 NamespaceURI Administered Info. RC3 NamespaceURI Administered Info. Ontology Component Dimensionality NamespaceURI Administered Info. metre NamespaceURI Administered Info. dimensionality NamespaceURI Administered Info. Ontology Atomic Construct length NamespaceURI Administered Info. KernelUnit NamespaceURI Administered Info. Unit NamespaceURI Administered Info. 18 東京電力・システム企画部・岡部雅夫 2007/12/07

  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. The prior version is identified by http://www.w3.org/TR/2003/CR-owl-guide-20030818/wine, which is also xmlns and xml:base. 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. 東京電力・システム企画部・岡部雅夫 2007/12/07

  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. A URI _2 Admin. Info. A URI _1 Admin. Info. RC3 NsURI_2 Admin. Info. RC1 NsURI_2 Admin. Info. RC2 NsURI_2 Admin. Info. RC1 NsURI_1 Admin. Info. RC2 NsURI_1 Admin. Info. RC3 NsURI_1 Admin. Info. Unit NsURI_2 Admin. Info. metre NsURI_2 Admin. Info. dimensionality NsURI_2 Admin. Info. Unit NsURI_1 Admin. Info. dimensionality NsURI_1 Admin. Info. metre NsURI_1 Admin. Info. length NsURI_2 Admin. Info. KernelUnit NsURI_2 Admin. Info. Dimensionality NsURI_2 Admin. Info. Dimensionality NsURI_1 Admin. Info. KernelUnit NsURI_1 Admin. Info. length NsURI_1 Admin. Info. completely different <ver. 2> <ver. 1> 20 東京電力・システム企画部・岡部雅夫 2007/12/07

  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 use use ontology A ver.2 ontology C ontology A ver.1 ontology B ontology A use use ontology B ontology C ver.1 ver.2 evolves 21 東京電力・システム企画部・岡部雅夫 2007/12/07

  22. What is MFI Ontology registration Ed1? What lacks in MFI Ontology registration Ed1? Evolution management in MFI Ontology registration Ed2 Other topics in MFI Ontology registration Overview of proposed Ed2 metamodel 東京電力・システム企画部・岡部雅夫 2007/12/07

  23. 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 東京電力・システム企画部・岡部雅夫 2007/12/07

  24. Overview: example1 evolves from ver.1 to ver.2 Some other metadata such as backward compatibility etc. A URI _2 Admin. Info. A URI _1 Admin. Info. RC3 NsURI_2 Admin. Info. RC1 NsURI_2 Admin. Info. RC2 NsURI_2 Admin. Info. RC1 NsURI_1 Admin. Info. RC2 NsURI_1 Admin. Info. RC3 NsURI_1 Admin. Info. Unit NsURI_2 Admin. Info. metre NsURI_2 Admin. Info. dimensionality NsURI_2 Admin. Info. Unit NsURI_1 Admin. Info. dimensionality NsURI_1 Admin. Info. metre NsURI_1 Admin. Info. length NsURI_2 Admin. Info. KernelUnit NsURI_2 Admin. Info. Dimensionality NsURI_2 Admin. Info. Dimensionality NsURI_1 Admin. Info. KernelUnit NsURI_1 Admin. Info. length NsURI_1 Admin. Info. • evolves <ver. 2> <ver. 1> • same • same • corresponds to 24 東京電力・システム企画部・岡部雅夫 2007/12/07

  25. 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/ • Since MFI Ontology registration is so generic, it should support all of them. 東京電力・システム企画部・岡部雅夫 2007/12/07

  26. 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. 東京電力・システム企画部・岡部雅夫 2007/12/07

  27. 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” 東京電力・システム企画部・岡部雅夫 2007/12/07

  28. 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. 東京電力・システム企画部・岡部雅夫 2007/12/07

  29. Case2 (2 of 2): example 3 evolves from ver.1 to ver.2 Some other metadata such as backward compatibility etc. A URI _2 Admin. Info. A URI _1 Admin. Info. • evolves <ver. 2> <ver. 1> RC1 NsURI_1 Admin. Info. RC3 NsURI_2 Admin. Info. RC2 NsURI_1 Admin. Info. RC1 NsURI_2 Admin. Info. RC2 NsURI_2 Admin. Info. RC3 NsURI_1 Admin. Info. • same • same metre NsURI_1 Admin. Info. KernelUnit NsURI_1 Admin. Info. length NsURI_1 Admin. Info. Unit NsURI_1 Admin. Info. Dimensionality NsURI_1 Admin. Info. dimensionality NsURI_1 Admin. Info. 29 東京電力・システム企画部・岡部雅夫 2007/12/07

  30. 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. 東京電力・システム企画部・岡部雅夫 2007/12/07

  31. ver.1 ver.2 ver.3 ver.4 ver.5 fork-type evolution 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 東京電力・システム企画部・岡部雅夫 2007/12/07

  32. What is MFI Ontology registration Ed1? What lacks in MFI Ontology registration Ed1? Evolution management in MFI Ontology registration Ed2 Other topics in MFI Ontology registration Ed2 Overview of proposed Ed2 metamodel 東京電力・システム企画部・岡部雅夫 2007/12/07

  33. 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 東京電力・システム企画部・岡部雅夫 2007/12/07

  34. 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 東京電力・システム企画部・岡部雅夫 2007/12/07

  35. Relation between reference and local ontology will be expanded A partial ordered set “Reusable Level” • MFI Ontology registration Ed2 will introduce a partial ordered set called “Reusable Level”. • There is an element RÎ “Reusable Level” • For any element e Î “Reusable Level”, e £ R • Example R L1 L2 L4 L5 L3 東京電力・システム企画部・岡部雅夫 2007/12/07

  36. Relation between reference and local ontology will be expanded 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. 東京電力・システム企画部・岡部雅夫 2007/12/07

  37. Relation between reference and local ontology will be expanded 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. 東京電力・システム企画部・岡部雅夫 2007/12/07

  38. Relation between reference and local ontology will be expanded Example • A reference ontology component can be reused by any ontology component since reference ontology component has maximum reusability R. R • 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. • 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. L1 L2 L4 L5 L3 東京電力・システム企画部・岡部雅夫 2007/12/07

  39. 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”. imports A B C-A1 C-B2 C-B1 C-A2 A-B2 A-B1 A-A1 A-A2 A-A3 A ontology whole C-A1 C-A2 C-B1 C-B2 ontology component ontology atomic construct A-B1 A-B2 A-A3 A-A1 A-A2 ontology sentence symbol 39 東京電力・システム企画部・岡部雅夫 2007/12/07

  40. 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. imports A B C-A1 C-A2 A-A1 A-A2 A-A3 ontology whole ontology component ontology atomic construct

  41. 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 41 東京電力・システム企画部・岡部雅夫 2007/12/07

  42. What is MFI Ontology registration Ed1? What lacks in MFI Ontology registration Ed1? Evolution management in MFI Ontology registration Ed2 Other topics in MFI Ontology registration Ed2 Overview of proposed Ed2 metamodel 42 東京電力・システム企画部・岡部雅夫 2007/12/07

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

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

  45. 東京電力・システム企画部・岡部雅夫 • Thank you for your attention. • MFI Ontology registration Ed2 WD is in preparation. • Any comments and/or contributions are very welcome to okabe.masao<at>tepco.co.jp.

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