Ontology from the perspective of
MMF Ontology Registry
OKABE, Masao
ISO/IEC JTC1 SC32/WG2 MMF Ontology Registry
UMTP (former CBOP)
4 November 2004
About MMF Project
MMF (Framework for Metamodel Interoperability)
ISO/IEC19763 (project leader: Hajime Horiuchi, Jp)
Part-1: Reference Model (Jp, UK)
Part-2: MMF Core (Jp, Kr)
Part-3: MMF Ontology Registry (Jp, Cn, Kr)
Part-4: MMF Model Mapping (Jp)
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About MMF Ontology Registry Project
A Joint project of experts from China, Korea and Japan
Main Editor:Hajime Horiuchi
Project members
Japan;
 Hajime Horiuchi (SC32-Jp, UMTP, Tokyo International Univ.)
 Masao Okabe (SC32-Jp, UMTP, TEPCO)
 Masaharu Obayashi (SC32-Jp, UMTP, K-three)
China;
 He Keqing (SC32-Cn, SKLSE, Wuhan Univ.)
 He Yangfan (SC32-Cn, SKLSE, Wuhan Univ.)
 Wang Chong (SC32-Cn, SKLSE, Wuhan Univ.)
Korea;
 Doo-Kwon Baik (SC32-Kr, Korea Univ.)
 Sam Oh (SC32-Kr, Sungkyunkwan Univ.)
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Abstract
MMF Ontology Registry links administration information to
the ontology stored conforming to ODM.
For that purpose, MMF Ontology Registry relies on DL
metamodel of ODM.
MMF Core
MMF Ontology Registry
MMF Ontology Registry
.
.
.
Registry Info. C
Registry
Info.
A
Ontology
Registry
Information
Ontology Registry Information
for Ontology A
for Ontology A
.
.
.
Ontology C
Ontology
A
for application
system C
for application system A
Registry Info. B
Ontology Registry Information
for Ontology B
Ontology Registry
Standardiz
Standardized
Ontology
Ontology
Repository
Repository
Ontology B
Standardized
Ontology
Repository
for application system B
ODM
Application
Application
System A
System A
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Inte rope ration
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Application
System B
4
Why is ontology?
Objectives of ontology from the point of MMF Ontology Registry
Mainly, to promote interoperability among various application systems.
More generally, to provide common base to communicate and
collaborate in some business domain or among deferent domains.
Background
Due to the proliferation of E-business and E-Commerce through the
internet, there are a lot of application systems available on the internet.
The number of available application systems is becoming larger and
larger.
The services provided by them evolve continuously.
Note
We think this view is within ODM and consistent with ODM
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What is ontology?
We support the definition in ODM RFP ad/2003-03-40.
ODM RFP ad/2003-03-40 says an ontology can range;
Taxonomy
 knowledge with minimal hierarchy or a parent/child structure
Thesaurus
 words and synonyms
Conceptual Model
 with more complex knowledge
Logical Theory
 with very rich, complex, consistent and meaningful knowledge
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What is ontology, compared with conceptual model?
 To actualize the our objectives of ontology,
ontology has a feature, compared with conceptual model.
That is,
Continuous and autonomous evolution
Ontologies have to evolve continuously and autonomously as each
application system evolves continuously and autonomously.
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Difficulty caused by autonomous evolution
This ontology has a
definition of ‘green card’
and does not have a
definition of ‘Christmas
card’.
Agent A
Ontology for
application
system A
This ontology does not
have a definition of
‘green card’ but has a
definition of ‘Christmas
card’.
Give me a ‘green card’.
Green card???
I can give you a Christmas card.
Christmas card???
Agent B
Ontology for
application
system B
To resolve this difficulty, source ontology is necessary.
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Source ontology and Local ontology
Source Ontology:
standardized ontology
for some business domain
pre-defined and relatively stable
Source
Ontology1
・
・
・
Source
Ontology3
Source
Ontology2
Local Ontology for
application system
B
Local Ontology for
application system
A
Local ontology :
localized ontology for some application system based on source ontologies
relatively unstable and evolves autonomously and continually
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Source Ontology and local ontology:Example
Source
Ontology
Agent A
Local
Ontology for
application
system A
Source Ontology +
Green Card is …
Card is …
Color is …
Certification is Green is …
…
Give me a green card.
What is a green card?
Is it a Christmas card whose color is green?
No. A green card is a certification
of working in the U.S.
Agent B
Local
Ontology for
application
system B
OK. I understand. Then, I cannot
give you a green card.
Source Ontology +
Christmas card is …
If agent A and B are human beings, this is easy task.
But if agent A and agent B are computer agents, this is not so easy task.
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What is necessary for computer agents.
For both source ontology and local ontology
Machine-understandable formal description
=> ODM’s matter
Administration information
registration authority identification
effective date
etc. based on ISO/IEC 11179-3 MDR Part 3
=>MMF Ontology Registry's matter
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Scope of MMF Ontology Registry
MMF Core
Scope of MMF Ontology Registry
MMF Ontology Registry
.
.
Registry Info. C .
Registry
Info.
A Information
Ontology
Registry
Ontology Registry Information
for Ontology A
for Ontology A
.
.
Ontology C .
Ontology
A
for application
system C
for application system A
Registry Info. B
Ontology Registry Information
Ontology Registry
Standardiz
Standardized
Ontology
Ontology
Repository
Repository
for Ontology B
Standardized
Ontology
Repository
Ontology B
for application system B
Scope of ODM
Application
Application
System A
System A
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Interoperation
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Application
System B
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Example one in ODM PRS 1 as source ontology
ODM
MMF Ontology Registry
Example1:Source_Onto
administration information
(PersonlCar:Concept):Atomic_Onto_Construct
administration information
(Car:Concept):Atomic_Onto_Construct
administration information
(Person:Concept):Atomic_Onto_Construct
administration information
(owns:Role):Atomic_Onto_Construct
administration information
(Vehicle:Concept):Atomic_Onto_Construct
administration information
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Other metaclasses with administration information
in MMF Ontology Registry
Onto_Domain
Source_Onto
Atomic_Onto_Construct
Local_Onto
SO_Component
SOC_Variant
Onto_Instances
Onto_Concepts
Onto_Selection
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Relation between ODM and MMF Ontology Registry
ODM
specifies ontology metamodel in several ontology descriptive languages
MMF Ontology Registry
links administration information to ontology stored conforming to ODM
relies on DL metamodel of ODM
because
 DL metamodel is the core of ODM
 two-way bounded mappings to/from DL and other ontology metamodels
such as OWL, Topic Maps etc. shall be provided.
Hence, we are very much interested in ODM, especially in
DL metamodel and have several comments and questions.
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Why is DL the core of ODM?
The main deference between DL and FOL is decidability,
which DL usually has but FOL does not.
Theoretically, decidability is very attractive.
But, practically, it might not matter.
Why does not ODM use FOL as its core,
although FOL is still complete.
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Comment on DL metamodel
in ODM PRS 1*
An expression is not necessarily in Tbox.
For example, an expression “Female  Person(ANNA)” is
in Abox.
*: Ontology Definition Metamodel Preliminary Revised Submission
to OMG RDP ad/2003-03-40 Volume1, 18 August 2004
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Comment on Example 3 in ODM PRS 1
(1/3)
DL does not have
a quantification
for a first
argument of an
atomic role.
DL does
not have
variables
See next two slides in detail.
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Comment on Example 3 in ODM PRS 1
(2/3)
Example 3 might be wrong in two points.
As FOL, this is correct.
The first point is that this uses x as a variable which is not
introduced in DL.
This situation sometimes happens because DL has only
quantification for the second argument of Role.
To resolve this situation, an inverse Role is necessary.
Then, we have; hasColor-.Car Color(red)
So, this is an A-box expression for red:individual and cannot
be a concept.
That is, “ c1:Concept” is not true.
This is the second point.
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Comment on Example 3 in ODM PRS 1
(3/3)
The diagram should be;
red : Literal
: Intersection
e1 : Expression
: Existential
e1 : Expression
Car : Concept
: Inverse
e1 : Expression
Color : DataType
hasColor : Role
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Example: MotherlessChildhasChild-. Woman
MotherlessChild:Concept
:Inverse
e1:Expression
:Definition
e2:Expression
:Universal
e3:Expression
e4:Expression
hasChild:Role
Woman:Concept
:Negation
It is not easy for DL metamodel to specify that e3 must be an expression
that can be defined as a role and that e4 must be an expression that
can be defined as a concept. (see next example also)
Does ODM intend to do this kind of things completely?
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Example: ParentWithDaughterhasChild. hasWife
ParentWithDaughter:Concept
e1:Expression
e2:Expression
:Inverse
:Definition
:Existential
e3:Expression
e4:Expression
hasChild:Role
hasWife:Role
:Negation
Obviously, this is a wrong example because hasWife is not a concept
but a role.
Does DL metamodel detect this kind of syntactical error completely?
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Example: FemaleChild(CatDog)
Female:Concept
Child:Concept
e1:Expression
:Intersection
Cat:Concept
e2:Expression
:Union
Dog:Concept
Is this diagram correct?
If yes, how can it is distinguished from (FemaleChild) CatDog.
If no, how does DL metamodel recognize the following two are same.
 Female(Child(CatDog))
 (FemaleChild)(CatDog))
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Question about two-way and bounded mapping on RFP
Two-way
According to the RFP
 An instance of the ODM metamodel can be translated into an instance of some
(e.g. OWL DL) metamodel and vice-versa.
Unclear point
 Since ‘can’ is not ‘must’, it is acceptable that some instances disappear through
the mapping. Is it correct?
 Bounded
According to the RFP
 Repeated applications of the two-way mapping does not result in continually large
user model.
Unclear point
 This means that through the mapping some information may lose but even finitelymany repeated applications may not result in nothing. Is it correct?
If they are correct, MMF Ontology Registry faces a problem because it
relies on DL metamodel even if ontology is described in other descriptive
languages.
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Asking for permission
 To promote the co-operation of ODM and MMF Ontology
Registry, it is a good idea to put ‘overview of ODM’ as an
annex of MMF Ontology Registry standard.
‘Overview of ODM’ shall be a summary of RFP and Revised
Submission Volume 1 and 2.
We need the copyrighters(Gentleware, DSTC, IBM,
Sandpiper )’ permission, because
‘Overview of ODM’ shall become open to all as an annex of MMF
Ontology Registry 2nd WD(or CD)
some sentences and diagrams in the overview might be similar to the
original ones.
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We are confident that the collaboration with ODM and
MMF Ontology Registry will bring a fruitful outcome.
Thank you.
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