1. OPM/S: Semantic Engineering of Web Services
Eran Toch
Instructors: Prof. Dov Dori & Dr. Iris Reinhartz-Berger
Technion – Israel Institute of Technology
Faculty of Industrial Engineering and Management
OPM Workshop – March 2004
Technion – Israel Institute of Technology

2. Agenda Background Motivation OPM/S – The Solution:
Engineering Process
OPM/S Modeling Framework
OPOSSUM
Evaluation and Contribution
Future Research
Technion – Israel Institute of Technology

3. Web Services
Web-based applications, accessible through standard XML interfaces:
Designed to work together following a business plan.
Aim to provide the corner stone of:
EAI (Enterprise Application Integration).
Ubiquitous (Mobile) and personal computing.
Inter organizational computing (B2B, supply chains, e-Gov…)
UDDI
SOUP
WSDL
Technion – Israel Institute of Technology

4. Web Services’ Integration – cont’d
Big names are busy integrating Web services…
Microsoft
BEA
IBM
Biztalk
WebLogic
Integration
IBM Websphere
Composer
Technion – Israel Institute of Technology

5. The Semantic Web
“The Semantic Web is an extension of the current web in which information is given well-defined meaning, better enabling computers and people to work in cooperation.”
Sir Tim Berners-Lee
Information can be given formal and common meaning, Using standard XML languages (RDF, OWL).
Domain knowledge can be mapped into Ontologies, providing common meta-data for the domain.
Products: RSS, FOAF, National Cancer Institute Ontology…
I should think of an example here
Technion – Israel Institute of Technology

6. Current Work - Semantic Web with OPM
VisWeb:
Representation of semantic in OPM.
Translating between RDF and OPM languages.
Domain Analysis Paradigm:
Specifying the domain description as an OPM model.
Domain elements specify roles in the system model.
The model can be validated against its domain representation.
Technion – Israel Institute of Technology

7. Semantic Web Services OWL-S is an ontology for Web services.
Web Services + Semantic Web = Semantic Web Services
OWL-S is an ontology for Web services.
Semantic Web Services can be used for automatic:
Discovery.
Invocation.
Composition and interoperation.
Monitoring.
Validation.
UI Creation.
Technion – Israel Institute of Technology

8. Semantic Web Services – An Example
Discovery
Invocation
Composition
OWL-S
OWL-S
Hospital Web Service
Healthcare
Web Service
Customer
Mobile Agent
Developers
Customer
Technion – Israel Institute of Technology

9. Research Motivation
Semantic Web Services did not cross the boundary between Industry and Academia.
Why?
OWL-S documents are powerful, but complex to model and understand.
Difficult reuse and composition.
Current engineering processes do not contain immediate return on effort.
Talk about the attitude.
Technion – Israel Institute of Technology

10. Research Objectives
Objective: To provide a human-accessible method for modeling and reusing Semantic Web Services.
Method:
Suggesting an engineering process that simplifies semantic modeling.
Modeling framework, based on OPM.
Utilizing automatic matching using OPOSSUM: A semantic/structural matching engine.
Technion – Israel Institute of Technology

11. External Services are notated as environmental
Engineering Process
External Services are notated as environmental
Geo ontology
Technion – Israel Institute of Technology

12. Engineering Process – cont’d
OPOSSUM
Search Results
Higher equivalence
Lower equivalence
Integrated Automatically
back to the model
Technion – Israel Institute of Technology

13. Engineering Process
Technion – Israel Institute of Technology

14. Modeling Framework Defining a meta-model for semantic Web services.
Extending OPM to support refined logical relations.
Extending the domain analysis paradigm.
Providing formal and operational mapping between OWL-S and OPM.
Technion – Israel Institute of Technology

15. OPOSSUM*
Enable to search through repositories of OPM/S and OWL-S specifications.
Presents an integration plan between two models.
Query model is specified in OPM, and target models are retrieved according to their Capability Equivalence.
Overcomes:
Differences in abstraction levels.
Sub models.
Partial matching.
* Object-PrOcess Structural / Semantic Unified Matching
Technion – Israel Institute of Technology

16. Capability Equivalence*
CP Represents the extent to which a target model (T) can be reused instead of a query model (Q):
General sketch of CP’s calculation algorithm:
Calculating semantic similarity.
Finding comparison paths.
Comparing the paths by FSA’s, including functional and structural equivalences
Calculating equivalence value as a weighted average over the path’s results.
* In Collaboration with Pnina Soffer
Technion – Israel Institute of Technology

17. Evaluation Theoretical: Empirical
Proving that OPM/S is compatible with OWL-S and WSDL.
Proving that capability equivalence based matching is stronger than semantic matching.
Empirical
Testing OPM/S modeling and composition on benchmark applications.
Technion – Israel Institute of Technology

18. Contribution General Community: OPM Community:
Easy to use modeling and development method for semantic Web services.
Prototype of a semantic matching engine for real life.
Byproduct: OWL-S API.
OPM Community:
Formal definition of the capabilities of an OPM model.
Matching algorithm for OPM models.
Extending OPM by adding further logical relations.
Research opportunities in Web services and Semantic Web.
Another example of a domain meta-model.
Technion – Israel Institute of Technology

19. Future Research
Comparative experiment, measuring Cognitive perception and readability of the model.
OWL mapping to OPM.
Using semantic meta-data to speed up engineering tasks.
UML-based approaches.
Security meta-model.
Model as a reverse auction – agent based composition.
OPM for personal needs specification (OPL as query language…)
Technion – Israel Institute of Technology