Universität Innsbruck Leopold Franzens  Copyright 2007 DERI Innsbruck Second TTF Technical Fair 12 December 2007 Mediation Component Second TTF Technical Fair Adrian Mocan, Emilia Cimpian, François Scharffe, Omair Shafiq DERI Innsbruck – University of Innsbruck

Members Adrian Mocan (Chair) – Coordinator –Instance Transformation –Abstract Mapping Language API François Scharffe –Ontology Alignment Representation Emilia Cîmpian –Process Mediation Omair Shafiq –Mediation support for Triple Space Computing and TripCom

3 Second TTF Technical Fair 12 December 2007 Overview New developments on ontology-based data mediation tools –Mediation in TSC and TripCom Business Process Mediation Ontology Alignment Representation

4 Second TTF Technical Fair 12 December 2007 Ontology-based data mediation Universität Innsbruck Leopold Franzens Second TTF Technical Fair  Copyright 2006 DERI Innsbruck Mediation Component 12 December 2007

5 Second TTF Technical Fair 12 December 2007 Context and Mediation Scenario Scenario: Approach: Context Web Service Modeling Ontology (WSMO)‏ Web Service Modeling Language (WSML)‏ Web Service Execution Environment (WSMX)‏ Design-time Semi-automatic approach for Ontology Mapping Run-time Automatic instance transformation

6 Second TTF Technical Fair 12 December 2007 Design-Time Ontology Mapping Tool Most important features: –Perspectives Different view-points on the ontology Allows to identify different types of mismatches –Bottom-up approach Training set –Top-down approach Decomposition, Contexts –Suggestions Lexical algorithms Structural algorithms –Consider the structure –Use the already creating mappings to improve the quality of suggestions Aim –To abstract the user from the burden on mappings creation process

7 Second TTF Technical Fair 12 December 2007 Run-Time Data Mediator Uses a reasoner to evaluate the mapping rules –WSML2Reasoner (MINS)‏ Outputs –Mediated data Target ontology instances Main Mediation Scenario: Instance Transformation Inputs –Incoming data Source ontology instances Features –Completely automatic process –Grounding of the abstract mappings to a concrete language F-Logic, WSML

8 Second TTF Technical Fair 12 December 2007 New features Imported Ontologies Mapping of inheritance hierarchies Transformation services Comparators Mappings testing (MUnit)

9 Second TTF Technical Fair 12 December 2007 New features Imported Ontologies The imported elements are distinctively marked Imported elements can be included/removed from the mapping views Focus can be changed to any of the imported ontologies

10 Second TTF Technical Fair 12 December 2007 New features Mapping of inheritance hierarchies A series of improvements regarding the mappings creation between inheritance hierarchies

11 Second TTF Technical Fair 12 December 2007 New features Mapping of inheritance hierarchies A series of improvements regarding the mappings creation between inheritance hierarchies Inherited Instance Transformation

12 Second TTF Technical Fair 12 December 2007 New features Mapping of inheritance hierarchies Every instance of G is an instance of B –Attribute b is mapped with the attribute d An instance of D is created as well But G has its own attribute g –An instance of H is created as well In fact only an instances of H should be created –In background extra rules need to be generated to state that “any instance of a subconcept of D can be a filler for c” –Post-processing includes methods for pruning the undesired instances We need to mediate an instance of G

13 Second TTF Technical Fair 12 December 2007 New features Mapping of inheritance hierarchies with conditions

14 Second TTF Technical Fair 12 December 2007 New features Transformation Services Used to compute new target values based on source values

15 Second TTF Technical Fair 12 December 2007 New features Transformation Services New service identifiers can be included at any time in the mapping process At run-time the reasoner just prepares the values needed for the invocation The service calls are resolved (i.e. invoked) in the post-processing step Assures independence on the reasoning support Unrestricted number of services can used in the mappings

16 Second TTF Technical Fair 12 December 2007 New features Conditions on literals and comparators Allows the usage of the InstanceOf view to create conditions on literals

17 Second TTF Technical Fair 12 December 2007 New Features Mapping Unit Test View The run-time component is embed in the design-time tool in order to allow the testing of the mappings

18 Second TTF Technical Fair 12 December 2007 Conclusions and Further Work The ontology-based data mediation tools are under active development New features to come: –Optimization for the run-time component To include in the reasoning space only the required fragments of the ontology and their corresponding mappings –Wizard for creating test cases –Flexible mechanisms for adding new resolvers for the transformation services

Mediation support for Triple Space Computing Data heterogeneity issues among different parties communication via Triple Space Need of Mediation support in Triple Space Computing (TSC)  Use of Abstract Mapping Language to specify Mapping Rules and grounding of Mapping Rules to RDF –Design Time  Design time tool for creation of mapping rules –Runtime  Architecture, APIs  RDF schema for grounding of mapping rules into RDF  Mediation Engine for Triple Space Computing middleware Current and Future Work –In TripCom Protocol Mediation, Message Mediation and Data Mediation Reusability of WSMX Data and Process Mediation Prototype development

20 Second TTF Technical Fair 12 December 2007 Process Mediation Universität Innsbruck Leopold Franzens Second TTF Technical Fair  Copyright 2006 DERI Innsbruck Mediation Component 12 December 2007

21 Second TTF Technical Fair 12 December 2007 Overview Requirements Process Mediation Approaches: –Run-time –Design-time Design-time Process Mediator, SUPER project approach

22 Second TTF Technical Fair 12 December 2007 Requirements I Example 1: Split message Example 2: Stop message Example 3: Inverse messages

23 Second TTF Technical Fair 12 December 2007 Requirements II

24 Second TTF Technical Fair 12 December 2007 Requirements II The Mediator Process has to control the execution of the other three process (as its sub-processes)‏ It may involve the change of some of the three sub-processes

25 Second TTF Technical Fair 12 December 2007 Process Mediation Approaches Run-time Process Mediation –Input 2 or more Choreographies –Output - –Advantage: Automatic –Disadvantage: Un-solvable mismatches Design-time Process Mediation –Input 2 or more BPMO Processes –Output 1 Mediator Process –Advantage: BA should be able to solve all the mismatches that may appear Executable by the SBPELEE –Disadvantage: Manual -> Semi-automatic

26 Second TTF Technical Fair 12 December 2007 Design-time Process Mediation - The SUPER project approach Use the BPMO editor to enable the Mediator Process design –Extract the entities relevant for the mediation from the input processes –Create the corresponding entities for the Mediator Process –Generate (fragments of) the Mediator Process –Validate totally or partially the Mediator Process

27 Second TTF Technical Fair 12 December 2007 Extract the entities relevant for the mediation Marketing Department Process

28 Second TTF Technical Fair 12 December 2007 Extract the entities relevant for the mediation Technical Department Process

29 Second TTF Technical Fair 12 December 2007 Mediator Process

30 Second TTF Technical Fair 12 December 2007 Mediator Process

31 Second TTF Technical Fair 12 December 2007 Mediator Process

32 Second TTF Technical Fair 12 December 2007 Extract the entities relevant for the mediation Customer Process

33 Second TTF Technical Fair 12 December 2007 Mediator Process

34 Second TTF Technical Fair 12 December 2007 Future Work Develop reduction mechanisms Synchronization, sequentiality –Ex: receive PO on one branch and send PO on the other => receive PO followed by send PO Integration with Data Mediator –data heterogeneity – mismatches have to be previously solved

35 Second TTF Technical Fair 12 December 2007 Ontology Alignment Representation Universität Innsbruck Leopold Franzens Second TTF Technical Fair  Copyright 2006 DERI Innsbruck Mediation Component 12 December 2007

36 Second TTF Technical Fair 12 December 2007 Ontology Alignment Representation What need to be represented ? –The correspondences between ontologies entities entities: Classes, Attributes, Relations relations: Equivalence, Subsumption conditions: domain and range values and types, occurrence. Values transformations (conversion, concatenation, aggregation)‏

37 Second TTF Technical Fair 12 December 2007 Ontology Alignment Representation How can the alignment task be performed –Design time Components (WSMT mapping editor)‏ Graphical Mapping Interfaces Matchers –Practical mediation tasks Ontology Merging Instance Transformation (WSMX Data Mediator)‏ Query Rewriting instance unification There is a need to communicate alignments between the components being part of the mediation process

38 Second TTF Technical Fair 12 December 2007 Ontology Alignment Representation How was it done until now ? –Encoding the alignment using axioms of the ontology language ex: OWL equivalent-class and subclass-of => limit the expressiveness of the alignments to be represented –Integrated systems Use their own representation => Limit the use of systems tool and algorithms

39 Second TTF Technical Fair 12 December 2007 Ontology Alignment Representation We developed an ontology alignment language –Expressive 1,1 to n,n correspondences between every ontological entities models conditions as restrictions on entities allows to specify data transformations –Abstract from the ontology language –Meant to be an exchange format

40 Second TTF Technical Fair 12 December 2007 Ontology Alignment Representation The alignment language as a pivot format in the data mediation process Matching Algorithm 2 Matching Algorithm 1 Graphical Mapping Interface Alignment Data Mediator Ontology Merging Algorithm Reasoner

41 Second TTF Technical Fair 12 December 2007 Ontology Alignment Representation Implementation –Three syntaxes: Abstract Syntax Surface syntax RDF syntax –APIs providing Parsers for the RDF and surface syntaxes Renderer/Exporters to –OWL-DL, WSML-Flight, SKOS, SWRL –Various tools (Matching Service, WSMX data mediator, OntoStudio, Storage service)‏

42 Second TTF Technical Fair 12 December 2007 Ontology Alignment Representation Ongoing and future works –Building a library of common correspondence patterns –Building more efficient matching algorithms based on patterns –Doing RDF data transformation through SPARQL Construct queries –Proposal for standardization (W3C)‏

Questions?