CS774 Term Project Semantic Web Services: Web Services Based on the Semantic Web

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CS774 Term ProjectSemantic Web ServicesWeb
Services Based on the Semantic Web

• 2003-12-08
• Young-Guk Ha

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Contents

• Project Status
• Web Services
• Semantic Web Services
• Web Service Agents
• Schedule

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References

• Semantic Web Services
• Sheila A. McIlraith, et al., Stanford Univ.
• IEEE Intelligent Systems, Mar. 2001
• Semantic Web Services and Processes Semantic
  Composition and Quality of Service
• Jorge Cardoso et al., Univ. of Georgia
• Tutorial at Federated Conferences On the Move to
  Meaningful Internet Computing and Ubiquitous
  Computer, Irvine CA, Oct. 2002
• Models and Languages for Describing and
  Discovering E-Services
• Fabio Casati and Ming-Chien Shan, Hewlett-Packard
• Tutorial at Semantic Web Working Symposium,
  Stanford, CA, Jul. 2001
• DAML Services DAML-S (OWL Services OWL-S)
• http//www.daml.org/services/
• Web Services
• http//www.w3.org/2002/ws/

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Project Status

• Information Retrieval System for the Semantic Web
• Knowledge Base for OWL
• OWL KB v0.9 developed
• Passes 76 of W3C approved entailment tests
• Web Ontology Inference Engine
• OWL inference engine v0.9 developed
• Fwd chaining-based OWL reasoning engine
• Web Ontology Server
• JSP-based Web test driver v0.9 developed
• Semantic Web Client
• Car A/S Knowledge Service Application
• Test Ontology
• Car, Part, A/S ontology

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The World Wide Web
500 million users and more than 1 billion pages
Web
URI, HTML, HTTP
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Evolution of The Web

• Serious Problems in information
• finding
• extracting
• representing
• interpreting
• and maintaining

Web
URI, HTML, HTTP
Intelligence
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Evolution of The Web (Contd)
Dynamicity
Web Services
UDDI, WSDL, SOAP
Bringing the computer back as a device for
computation
Semantic Web
Web
RDF(S), DAML, OWL
URI, HTML, HTTP
Intelligence
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Evolution of The Web (Contd)
Bringing the web to its full potential
Dynamicity
Web Services UDDI, WSDL, SOAP
Semantic Web Services DAML-S, OWL-S
Semantic Web RDF(S), DAML, OWL
Web URI, HTML, HTTP
Intelligence
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Web Services

• Self-contained, self-describing, modular
  applications that can be published, located, and
  invoked across the Web (cf. RPC, CORBA, Java RMI)
• Web Service Provider
• Web Service Requestor
• Web Service Registry

Client App
HTTP
Service Requestor
Web Service Provider
Service Registry
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Web Service Invocation
Service Requestor
Registry (UDDI)
Service Discovery
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Web Service Lookup
Query
Service Matchmaking
WSDL
Client Code Generation
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Service Publication
Service Provider
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Service Invocation (SOAP)
Invoke Web Service
Web Service
Request
Service Description (WSDL)
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Response
WSDL Web Service Description Language SOAP Simple
Object Access Protocol UDDI Universal
Description, Discovery and Integration
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Web Service Description

• A Web service provider needs to provide
• Operations it supports (Inputs. Outputs)
• Transport and messaging protocols (HTTP, SOAP)
• Endpoint of the Web service (URI)
• A service requestor needs to analyze a service
  for
• Service discovery query, matchmaking
• Service invocation input, output
• Service composition (as a process)
  interoperability
• Description Language
• WSDL ? Describes the syntactic information of a
  service
• Cf. IDL in CORBA

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WSDL Example
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Web Service Composition

• Combining and linking existing Web Services and
  other components to create new processes (cf.
  Workflow systems)
• Web Service Discovery
• Web Service Integration
• Process Execution, Monitoring and Transaction
  Management

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Considerations for Intelligent Web Agents

• When agents discover Web Services
• In traditional workflow processes, selection of
  tasks is made from a repository and humanly
  manageable
• But in the Web environment, Potentially millions
  of Web services are available
• Very difficult to browse through all of the Web
  services available and select the most suitable
  ones
• When Web Services are put together
• Their interfaces need to interoperate
• Syntactic heterogeneity can be resolved with WSDL
• And also semantic heterogeneity need to be
  resolved

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Considerations for Intelligent Web Agents (Contd)

• Syntactic Heterogeneity
• Names and types of the terms can be resolved with
  syntactic service description
• Semantic Heterogeneity
• How to understand the intended meaning of the
  terms used in labeling interface parameters?

Voucher
Employee
Receipt
Client
Itinerary
Postal Addr
Travel Info
Mail Addr
Email
Tourism
Web Service
Web Service
Web Service
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Semantic Web Services

• Describing Services with Web Service Ontology
• Web Service ontology defines markup for
  describing Web services using Web ontology
  languages
• To infer from markups, appropriate inference
  engine is required
• Domain-independent ontology (upper ontology)
• DAML-S (DAML Services)
• OWL-S (OWL Services)
• Domain-specific ontology
• Based on upper ontology
• Domain-dependent knowledge on services
• Service profile hierarchy
• Service process modeling
• Service grounding

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DAML Services

• DAML-S (OWL-S) contains
• Markups for service profile
• Describing what the service does
• IOPEs (Input, Output, Precondition, Effects)
• Markups for service modeling
• Describing how it works
• Process, Parameter, Sequence,
• Markups for service grounding
• Describing how to access it
• Protocol, Messages,

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A Service Profile Hierarchy
damlClass
serviceServiceProfile
profileProfile
profileHierarchyInformation_Service
profileHierarchyE_Commerce
profileHierarchyBookSelling
profileHierarchyAirlineTicketing
congoProfileProfile_Congo_BookBuying_Service
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A Service Profile Instance

• ...
• lt!ENTITY temporal "http//ovid.cs.uga.edu8080/scu
  be/daml/Temporal.daml"gt
• lt!ENTITY address "http//ovid.cs.uga.edu8080/scub
  e/daml/Address.daml"gt
• ...
• ltinputgt
• ltprofileParameterDescription rdfID"Addr"gt
• ltprofileparameterNamegtAddrlt/profileparameterNam
  egt
• ltprofilerestrictedTo rdfresource"addressAdd
  ress"/gt
• ltprofilerefersTo rdfresource"congocongoBuyR
  eceipt"/gt
• lt/profileParameterDescriptiongt
• lt/inputgt
• ...
• ltoutputgt
• ltprofileParameterDescription rdfID"When"gt
• ltprofileparameterNamegtWhenlt/profileparameterNam
  egt
• ltprofilerestrictedTo rdfresource"temporalDa
  te"/gt
• ltprofilerefersTo rdfresource"congocongoBuyR
  eceipt"/gt
• lt/profileParameterDescriptiongt
• lt output gt

Outputs
Inputs
When
Addr
...
,,,
...
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Web Service Agents
Web Service Agent
Inference Engine
Phone
Contact
PersonalInfo Web Service
BookSelling Web Service
Credit Card
Payment
Postal Addr
Addr
DAML-S (OWL-S)
DAML-S (OWL-S)
Service Registry
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Schedule

• 2003-09-22
• Project proposal
• 2003-10-13
• Technology analysis report
• 2003-11-03
• Mid-term report
• 2003-11-17
• Implementation progress report
• 2003-12-08
• Semantic Web Services
• 2003-12-15
• Final report and demonstration