1.  Copyright 2005 Digital Enterprise Research Institute. All rights reserved. www.deri.org WSMX Data Mediation Adrian Mocan adrian.mocan@deri.org

2. 07.04.20052 Content WSMX Data Mediation - objectives, scenario, approach Design-Time –GUI –Semiautomatic mapping –Views Run-Time –Architecture –Usage Conclusions and Further Developments

3. 07.04.20053 Overview on WSMX Data Mediation Approach Objectives –To mediate the interchanged messages part of a communication process –To keep the communication process transparent from data representation point of view –To have a semi-automatic mediation process Assumptions: –Ontological approach to Data Mediation –Communicating parties express data in terms of an ontology –Interchanged messages → ontology instances –Ontologies conform to WSMO conceptual model for ontologies

4. 07.04.20054 Scenario Ontological Approach Ontology Merging Ontology Alignment »Instances Transformation

5. 07.04.20055 Ontological Approach Ontology Merging Ontology Alignment »Instances Transformation Data Mediation Prototype

6. 07.04.20056 Design Time Design Time Component → Ontology Mapping System Inputs –Source Ontology and Target Ontology Features –Graphical interface to the human user –Set of mechanism towards semi-automatic creation of mappings –Capturing the semantic relationships identified in the process –Storing these mappings in a persistent storage Output –Abstract representation of the mappings DIP/SEKT mapping language

7. 07.04.20057 Design Time Component – Features Graphical Interface Browsing the ontologies Guide the human user Views based approach Top-down vs Bottom-up Approach –Top-Down Start from a specific problem to solve Determine all the related elements for that mapping –Bottom-Up Identify the minimal common subset Contexts Not all the information in the ontology are relevant for a specific mapping creation step Updated by applying decomposition

8. 07.04.20058 Design Time Component – Features Views (I) View –Covers only certain aspects of the ontology –Associate roles to the elements part of that view –Strategies and algorithms are applied on roles –The same algorithms and strategies can be used across the views Roles –Primitive Item –Compound Item –Description Item Has a Successor which could be either a Primitive or Compound item Two views are maintained: one for the source and one for the target ontology

9. 07.04.20059 Design Time Component – Features Views (II) primitive_item1 compound_item1 ├ hasDescription1 → compound_item2 └ hasDescription2 → primitive_item1 primitive_item2 primitive_item3 compound_item2 ├ hasDescription1 → primitive_item3 └ hasDescription2 → compound_item3 compound_item3 ├ hasDescription1 → primitive_item2 ├ hasDescription2 → primitive_item1 └ hasDescription3 → primitive_item3

10. 07.04.200510 primitive_item1 compound_item1 ├ hasDescription1 → compound_item2 └ hasDescription2 → primitive_item1 primitive_item2 primitive_item3 compound_item2 ├ hasDescription1 → primitive_item3 └ hasDescription2 → compound_item3 compound_item3 ├ hasDescription1 → primitive_item2 ├ hasDescription2 → primitive_item1 └ hasDescription2 → primitive_item3 Design Time Component – Features Decomposition

11. 07.04.200511 primitive_item1 compound_item1 ├ hasDescription1 → compound_item2 └ hasDescription2 → primitive_item1 primitive_item2 primitive_item3 compound_item2 ├ hasDescription1 → primitive_item3 └ hasDescription2 → compound_item3 compound_item3 ├ hasDescription1 → primitive_item2 ├ hasDescription2 → primitive_item1 └ hasDescription2 → primitive_item3 Design Time Component – Features Decomposition

12. 07.04.200512 Design Time Component – Features Decomposition → Contexts primitive_item1 compound_item1 ├ hasDescription1 → compound_item2 └ hasDescription2 → primitive_item1 primitive_item2 primitive_item3 compound_item2 ├ hasDescription1 → primitive_item3 └ hasDescription2 → compound_item3 compound_item3 ├ hasDescription1 → primitive_item2 ├ hasDescription2 → primitive_item1 └ hasDescription2 → primitive_item3 Reveals the description of the decompose item Updates the contexts Description of the decomposed item Ends when there no compound items to decompose

13. 07.04.200513 The semantic relationships → mappings Critical step –Links the graphical representation of mappings with their abstract representation –Hides the complexity of the mappings from the human user Each time a pair of items is chosen a set of mappings are created Different views imply different mappings for the same action Design Time Component – Features Capturing the semantic relationships

14. 07.04.200514 Design Time Component – Features Towards Semi-automatic Mappings Domain expert role: –To choose pairs of items from the source and target to be decomposed –Each pair denotes a semantic relationship Suggest semantic relationships –Lexical Algorithms Applicability: primitive/compound items & description Uses lexical relationships between items names WordNet + string analyze algorithms –Structural Algorithms Applicability: compound items Based on –the already done mappings –items descriptions Uses the decomposition algorithm

15. 07.04.200515 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept

16. 07.04.200516 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept class to class mapping (classMapping)

17. 07.04.200517 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept class to class mapping (classMapping)

18. 07.04.200518 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept class to class mapping (classMapping) attribute to attribute mapping (attributeMapping) class to class mapping (classMapping)

19. 07.04.200519 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept class to class mapping (classMapping) attribute to attribute mapping (attributeMapping) class to class mapping (classMapping)

20. 07.04.200520 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept class to class mapping (classMapping) class to attribute mapping (classAttributeMapping)

21. 07.04.200521 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept class to class mapping (classMapping) attribute to class mapping (classAttributeMapping)

22. 07.04.200522 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept

23. 07.04.200523 primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept Design Time Component – Features Capturing the semantic relationships – PartOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_concept (data type) compound_concept ├ attribute1 → primitive_concept └ attribute2 → compound_concept

24. 07.04.200524 Design Time Component – Features Capturing the semantic relationships – InstanceOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance

25. 07.04.200525 Design Time Component – Features Capturing the semantic relationships – InstanceOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance

26. 07.04.200526 Design Time Component – Features Capturing the semantic relationships – InstanceOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance class to class mapping (classMapping)

27. 07.04.200527 Design Time Component – Features Capturing the semantic relationships – InstanceOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance class to class mapping (classMapping) attribute to attribute mapping (attributeMapping) –(2x) attribute value condition (valueCondition)

28. 07.04.200528 Design Time Component – Features Capturing the semantic relationships – InstanceOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance class to class mapping (classMapping) attribute to attribute mapping (attributeMapping) –(2x) attribute type condition (typeCondition)

29. 07.04.200529 Design Time Component – Features Capturing the semantic relationships – InstanceOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance class to class mapping (classMapping) class to attribute mapping (classAttributeMapping) –attribute type condition (typeCondition)

30. 07.04.200530 Design Time Component – Features Capturing the semantic relationships – InstanceOf View primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_item compound_item ├ hasDescription1 → primitive_item └ hasDescription2 → compound_item primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance primitive_instance compound_instance ├ attribute1 → primitive_instance └ attribute2 → compound_instance class to class mapping (classMapping) class to attribute mapping (classAttributeMapping) –attribute type condition (typeCondition)

31. 07.04.200531 Run Time Run Time Component – Data Mediator Inputs –Incoming data Source ontology instances Features –Completely automatic process –Grounding of the abstract mappings to a concrete language Flora2 –Uses the services of a reasoner to evaluate the mapping rules Flora2 reasoner Outputs –Mediated data Target ontology instances

32. 07.04.200532 Run Time Component - Architecture Abstract Mappings Repr. Flora Rules Generator Instance Source Flora2/XSB Environment Flora Mapping Rules Mappings Instance Target Ontologies

33. 07.04.200533 Run Time Component – Features (I) Grounding the abstract mappings Associate a formal semantics to the mappings –Obtain rules in a concrete language Why not during design time? –Offers a grater flexibility –Different groundings for the same mappings set –Different execution environments for the grounded mappings –Easier to maintain the abstract mappings –Important point of alignment Cashing mechanism can be used

34. 07.04.200534 Run Time Component – Features (II) Reasoning on the mapping rules –Flora2/XSB as an execution environment for the mapping rules Java Wrapper around Flora2 reasoner –Declarativa Interprolog http://www.declarativa.com/interprolog/ http://www.declarativa.com/interprolog/ Steps: –Abstract mapping loaded from the storage Relational database –Grounded to Flora2 -> Flora2 rules –Flora2 Rules loaded in Flora2 reasoner –Incoming instances loaded in Flora2 reasoner –The result (mediated instances) retrieve from the reasoner

35. 07.04.200535 Conclusions and Future Work Design Time Tool –Fills the gap between graphical representation of the mappings and the formal representation of these mappings –Abstract the human user from the logical representation of the mappings Run-Time Tool –An automatic mediation system based on already identified mappings between source and target Future Work –Identify more relevant views and the correspondences to the mapping language –Enhanced the assisted aspect of the design-time tool –Evaluation tests of the run-time tool

36. 07.04.200536 Useful links Code –http://sourceforge.net/projects/wsmx/http://sourceforge.net/projects/wsmx/ Documentation –http://www.wsmo.org/TR/d13/d13.3/v0.2/http://www.wsmo.org/TR/d13/d13.3/v0.2/