Algebraic Graph Transformations for Merging Ontologies

Context Typed Graph Grammars Approach Implementation Conclusion References

Algebraic Graph Transformations for MergingOntologies

Mariem MAHFOUDH, Laurent THIRY, Germain FORESTIERand Michel HASSENFORDER

{mariem.mahfoudh, laurent.thiry, germain.forestier, michel.hassenforder}@uha.fr

UHA–MIPS, EA 2332 /ENSISA, 12 rue des Freres Lumiere68093 Mulhouse Cedex, France

International Conference on Model & Data Engineering (MEDI 2014)Larnaca, Cyprus, 25 September 2014

M.Mahfoudh et al. Merging Ontologies with SPO 1/25


Outline

1 Context

2 Typed Graph Grammars

3 Approach

4 Implementation

5 Conclusion



Outline

1 Context


3 Approach

4 Implementation

5 Conclusion



Context

European project CCAlps (Creative Companies in Alpine space)

Aims:

I Help and facilitate the collaboration between creativecompanies in Alpine Space

I Link several companies and partners to organize events

Idea

I Use ontologies to model data and build a consensus betweenthe various partners

Web site: www.ccalps.eu



Ontologies

I Ontologies are an explicit specification of a conceptualizationof a domain [Gruber, 1993]



Ontologies




Ontologies


⇒ Require concepts, methods and tools to merge ontologies



Merging ontologies

I Merging ontologies is defined as ”Creating a new ontologyfrom two or more existing ontologies with overlapping parts,which can be either virtual or physical” [Klein, 2001]

Similarity search

Merging ontologies:Create a global ontology

Symmetric

Asymmetric

O1 O2

GO

Merging ontologies process

Similarity search


Symmetric

Asymmetric

O1 O2

GO


⇒ Define an asymmetric approach for merging ontologies using TypedGraph Grammars to reduce the conflicts in the Global Ontology



Merging ontologies

I Merging ontologies is defined as ”Creating a new ontologyfrom two or more existing ontologies with overlapping parts,which can be either virtual or physical” [Klein, 2001]

Similarity search


Symmetric

Asymmetric

O1 O2

GO


⇒ Define an asymmetric approach for merging ontologies using TypedGraph Grammars to reduce the conflicts in the Global Ontology



Outline

1 Context


3 Approach

4 Implementation

5 Conclusion



Typed Graph Grammars

I Formalism for the representation and management of graphs

I Let TGG = (G ,GT ,P) be a typed graph grammar where:

B G = (V ,E ) is a host graphB GT = (VT ,ET ) is a type graph

PACMan game with TGG, [Ehrig and Padberg, 2004].




I Formalism for the representation and management of graphs

I Let TGG = (G ,GT ,P) be a typed graph grammar where:

B G = (V ,E ) is a host graphB GT = (VT ,ET ) is a type graph

PACMan game with TGG, [Ehrig and Padberg, 2004].




TGG = (GT ,G ,P)

I P = (LHS ,RHS) is a set of production rules:

B LHS (Left Hand Side) represents the precondition of therewriting rule and defines the structure that has to be found inG .

B RHS (Right Hand Side) represents the postcondition of therewriting rule and must replaces LHS in G .

⇒ NAC (Negative Application Condition) specify the graphthat should not occur when matching a rule.

More details: [Rozenberg, 1999]M.Mahfoudh et al. Merging Ontologies with SPO 9/25


Simple PushOut (SPO)

I Applying a rewriting rule to an initial graph (G ) with the SPOmethod consists in:

1 Finding LHS in G by defining a morphism m : LHS → G2 Deleting m(LHS)−m(LHS ∩ RHS) from G3 Adding m(RHS)−m(LHS ∩ RHS) to G to get a new version

G ′

m

Rewriting rule with PACMan game [Ehrig and Padberg, 2004].



Outline

1 Context


3 Approach

4 Implementation

5 Conclusion



A graph transformation model for ontology changes

TGG = (G ,GT ,P)

I G describes the ontology

I GT represents the ontologies meta-model

Type Graph for representing ontologies.



A graph transformation model for ontology changes

TGG = (G ,GT ,P)

I P represents the ontologies changes

G

LHS RHS

domain

name="Location"

Class

name="hasLocation"

ObjectProperty

name="Company"

1:Class

name="Entreprise"

1:Class

NAC

name="Entreprise"

Class

RenameClass

m

name="Company"Class

range

G'

domain

name="Location"

Class

name="hasLocation"

ObjectProperty

name="Entreprise"Class

range

M. Mahfoudh, G. Forestier, L. Thiry, and M. Hassenforder, ”Consistent ontologiesevolution using graph grammars”, International Conference on Knowledge Science,Engineering and Management, Dalian (Chine), pages 64-75, Springer, 2013.



Merging ontologies with SPO

Approach

I Asymmetric approach for merging ontologies

I Approach based on algebraic graph transformations

O1 O2

Step1: Similarity search

Step 2: Merge

Step 3: Adaptation

CO O2

O1 GO GO'

LHSCH RHSCH

SPO

SPO*

Approach of merging ontologies with algebraic graph transformations.



Step 1: similarity search

Similarity search

I Define the correspondences between the ontologies O1 andO2:

1 Common nodes (CN)2 Equivalents nodes (EN)3 Nodes sharing a semantic relation (SN)4 Nodes sharing a subsumption relation (IsaN)



Step 1: similarity search

EOCCAlps ontology extract COCCAlps ontology extract

Similarity search example

I CN = {”Tag”}; EN = {(”hasTag”, ”has Tag”)}I SN = {(”Emplacement”, ”Location”)}I IsaN = {(”Company”, ”Participant”)}



Step 2: merging ontologies

EN{O1} EN{O2}

O1 O'1

CO O2

O'1 GO

(LHS) (RHS)

(G) (G')

(LHS) (RHS)

(G) (G')

O'1 O2

CO

Sub-step1 Sub-step2 Sub-step3

Merging ontologies

1 Minimize the differences between the two ontologies.⇒ ∀N ∈ {EN} doO ′

1 ← SPO RenameEntity (O1, EN{O1}, EN{O2} )

2 Create the common ontology (CO)

3 Create the global ontology (GO)⇒ GO ← SPO MergeGraph (O ′

1, CO, O2)



Step 3: global ontology adaptation

Global ontology adaptation

I Enrich the global ontology by adding the semantic andsubsumption relations

LHS

1:Class

name="C1"

2:Class

name="C2"

RHS

2:Class

name="C2"

1:Class

name="C1"

subClassOf subClassOf

NAC5

1:Class

name="C1"

disjointwith

Class

2:Class

name="C2"

Class

subClassOf subClassOf

subClassOf

NAC1

1:Class

name="C2"

2:Class

name="C1"

NAC2

1:Class

name="C2"

2:Class

name="C1"

disjointWith

NAC3

1:Class

name="C2"

2:Class

name="C1"

NAC4

2:Class

name="C2"

subClassOf

1:Class

name="C1"

Class

subClassOf

Rewriting rule for the AddSubClassChange.



Step 3: global ontology adaptation

Result of merging the ontologies O1&O2

Global ontology adaptation example

I SN = {(”Emplacement”, ”Location”)}I IsaN = {(”Company”, ”Participant”)}



Outline

1 Context


3 Approach

4 Implementation

5 Conclusion



Implementation

I Implementation of two java prototypes:

B OntologiesMapping is based on WordNet ontology andLevenshtein distance

B GROM (Graph Rewriting for Ontology Merging) is based onAGG (Algebraic Graph Grammar) API

OntologiesMapping

GROM

O1 (.owl)

O2 (.owl)

MappingFile(.xml)

GO (.ggx)

GGXToOWL

OWLToGGX

O1 (.ggx)

O2 (.ggx)

GO (.owl)

Web site: http://mariem-mahfoudh.info/medi2014M.Mahfoudh et al. Merging Ontologies with SPO 21/25


Outline

1 Context


3 Approach

4 Implementation

5 Conclusion



Conclusion

Summary

I Propose an asymmetric approach for merging ontologies usingtyped graph grammar and algebraic graph transformations

I Implement the approach and propose GROM tool

Future work

I Study large ontologies

I Study the conflicts in details



References

Hartmut Ehrig and Julia Padberg. Graph grammars and petri net transformations. InLectures on Concurrency and Petri Nets, pages 496–536. Springer, 2004.

Thomas R. Gruber. A translation approach to portable ontology specifications.Knowledge acquisition, 5(2):199–220, 1993.

Michel Klein. Combining and relating ontologies: an analysis of problems andsolutions. In IJCAI-2001, Workshop on ontologies and information sharing, pages53–62, 2001.

Michel Klein. Change Management for Distributed Ontologies. PhD thesis, VrijeUniversiteit Amsterdam, Amsterdam, The Netherlands, 2004.

Mariem Mahfoudh, Germain Forestier, Laurent Thiry, and Michel Hassenforder.Consistent ontologies evolution using graph grammars. In Knowledge Science,Engineering and Management, pages 64–75. Springer, 2013.

Salvatore Raunich and Erhard Rahm. Towards a benchmark for ontology merging. InOn the Move to Meaningful Internet Systems: OTM 2012 Workshops, pages124–133. Springer, 2012.

Grzegorz Rozenberg. Handbook of graph grammars and computing by graphtransformation, volume 1. World Scientific, 1999.



Thank you for your attention

Contact: [email protected] site: www.mariem-mahfoudh.info


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Algebraic Graph Transformations for Merging Ontologies