Noman Islam

1
OWL Current Status

• OWL 1.1
• OWL 2.0 Working Draft
• http//www.w3.org/TR/2008/WD-owl2-syntax-20080411/
  
• OWL Mailing List
• http//lists.w3.org/Archives/Public/public-owl-dev
  /
• OWL API
• http//owlapi.sourceforge.net/releases.html (17th
  April 2008 )

2
An African Wildlife Ontology 5

• ltrdfRDF
• xmlnsrdf"http//www.w3.org/1999/02/22-rdf-syntax
  -ns"
• xmlnsrdfs"http//www.w3.org/2000/01/rdf-schema"
  
• xmlnsowl "http//www.w3.org/2002/07/owl"
• xmlns"http//www.mydomain.org/african"gt
• ltowlOntology rdfabout""gt
• ltowlVersionInfogt
• My example version 1.2, 17 October 2002
• lt/owlVersionInfogt
• lt/owlOntologygt
• ltowlClass rdfID"animal"gt
• ltrdfscommentgtAnimals form a classlt/rdfscommentgt
• lt/owlClassgt
• ltowlClass rdfID"plant"gt
• ltrdfscommentgt
• Plants form a class disjoint from animals
• lt/rdfscommentgt
• ltowldisjointWith"animal"/gt
• lt/owlClassgt

3
An African Wildlife Ontology

• ltowlClass rdfID"carnivore"gt
• ltrdfscommentgtCarnivores are exactly those
  animals
• that eat also animalslt/rdfscommentgt
• ltowlintersectionOf rdfparsetype"Collection"gt
• ltowlClass rdfabout"animal"/gt
• ltowlRestrictiongt
• ltowlonProperty rdfresource"eats"/gt
• ltowlsomeValuesFrom rdfresource"animal"/gt
• lt/owlRestrictiongt
• lt/owlintersectionOfgt
• lt/owlClassgt
• lt/rdfRDFgt

4
OWL-S

• Ontology
• O ltc, p, agt
• Web Service
• Service ltd,f,pgt
• OWL-S 1.2
• http//www.daml.org/services/owl-s/
• four fundamental points
• Service
• Profile
• Process
• Grounding

5
OWL-Service

• presents, describedBy, and supports
• ltserviceService rdfID"BravoAir_ReservationAgent
  "gt
• ltservicepresents rdfresource"BravoAirProfile.ow
  lProfile_BravoAir_ReservationAgent"/gt
• ltservicedescribedBy rdfresource"BravoAirProcess
  .owlBravoAir_Process" /gt
• ltservicesupports rdfresourceBravoAirGrounding.o
  wlGrounding_BravoAir_ReservationAgent"/gt
• lt/serviceServicegt

Service Ontology 4
6
OWL-S Profile

• human-readable information like serviceName,
  textDescription and contactInformation
• Functional description
• IOPE
• Inputs and Outputs
• Preconditions and effects
• Other features include categories, quality of
  service parameters and an unbounded list of other
  parameters

7
OWL-S Service Model

• Inputs and Outputs
• Preconditions and effects
• Conditioning outputs and effects
• SWRL
• Process Types
• Atomic Process
• Simple Process
• Composite Process
• Sequence, split, choice, if-then-else, iterate
  etc.
• Participants

8

• ltprocesshasResultgt
• ltprocessResultgt
• ltprocesshasResultVargt
• ltprocessResultVar rdfID"CreditLimH"gt
• ltprocessparameterType rdfresource"ecomDollar
  s"/gt
• lt/processResultVargt
• lt/processhasResultVargt
• ltprocessinCondition expressionLanguage"exprKI
  F" rdfdataType"xsdstring"gt
• (and (current-value (credit-limit ?CreditCard)
• ?CreditLimH)
• (gt ?CreditLimH ?purchaseAmt))
• lt/processinConditiongt
• ltprocesswithOutputgt
• ltprocessOutputBindinggt
• ltprocesstoParam rdfresource"ConfirmationNum"/gt
  

9
OWL-S Groundings

• A predefined grounding, mapping to WSDL
• OWL-S atomic process is mapped to WSDL operation
• Why OWL-S?

2 Comparison of WDL and OWL-S for semantic web
10

• WSDL Grounding
• ltgroundingWsdlAtomicProcessGrounding
  rdfID"WsdlGrounding_GetDesiredFlightDetails"gt
• ltgroundingowlsProcess rdfresource"BravoAirProce
  ss.owlGetDesiredFlightDetails"/gt
• ltgroundingwsdlOperation rdfresource"GetDesired
  FlightDetails_operation"/gt
• ltgroundingwsdlInputMessage rdfdatatype"xsdany
  URI"gt
• BravoAirGrounding.wsdlGetDesiredFlightDetails_Inp
  ut
• lt/groundingwsdlInputMessagegt
• ltgroundingwsdlInputgt
• ltgroundingWsdlInputMessageMapgt
• ltgroundingowlsParameter rdfresource"BravoAirPro
  cess.owlDepartureAirport"/gt
• ltgroundingwsdlMessagePart rdfdatatype"xsdanyU
  RI"gt
• BravoAirGrounding.wsdldepartureAirport
• lt/groundingwsdlMessagePartgt
• lt/groundingWsdlInputMessageMapgt
• lt/groundingwsdlInputgt
• ...

In WSDL Description ltoperation
name"GetDesiredFlightDetails_operation"
owl-s-process"BravoAirGetDesiredFlightDetails"gt
ltinput message"tnsGetDesiredFlightDetails_Input
"/gt lt/operationgt ltmessage name"GetDesiredFlightDe
tails_Input"gt ltpart name"departureAirport"
owl-s-parameter"BravoAirdepartureAirport_In"
/gt ... lt/messagegt
11
WSMO

• WSMO Elements
• Ontologies
• Goals
• WebServices
• Capabilities
• Interfaces (choreography, orchestration)
• Mediators

WSMO Core Elements 3
12
An Example of WSMO

• goal ltlthttp//www.wsmo.org/2004/d3/d3.2/v0.1/20041
  004/resources/goal.wsmlgtgt
• nonFunctionalProperties
• dcdescription hasValue "Buying a train ticket
  from Innsbruck to Frankfurt on..."
• ...
• endNonFunctionalProperties
• importedOntologies ltlthttp//www.wsmo.org/ontologie
  s/dateTimegtgt
• ...
• webservice ltlthttp//www.wsmo.org/2004/d3/d3.2/v0.1
  /20041004/resources/ws.wsmlgtgt
• nonFunctionalProperties
• ...
• dcdescription hasValue "Web Service for booking
  online train tickets for Austria and Germany"
• ...
• endNonFunctionalProperties
• importOntologies ltlthttp//www.wsmo.org/ontologies
  /dateTimegtgt,
• ltlthttp//www.wsmo.org/ontologies/trainConnectiongt
  gt,
• ltlthttp//www.wsmo.org/ontologies/purchasegtgt,
• ltlthttp//www.wsmo.org/ontologies/locationgtgt
• capability _
• ...

13
Ontology Reasoning

• Reasoning is provided mapping ontology language
  to a known logical formalism
• OWL is mapped on a description logic
• Reasoners like FaCT and RACER
• We may reason about
• Class membership
• Equivalence of classes - denote the same set in
  any legal world description
• In consistency -denotes the empty set in any
  legal world description.
• Classification

14
Ontology Languages and related standards 1
15
References

• Ontology Language Standardisation Efforts,
  OntoWeb Ontology-based Information Exchange for
  Knowledge Management and Electronic Commerce,
  2002
• Web service interface description languages,
• A Conceptual Comparison between WSMO and OWL-S,
  WSMO Working Draft, January 6, 2005
• OWL-S Semantic Markup for Web Services, W3C
  Member Submission 22 November 2004
• Web Ontology Language OWL, Grigoris Antoniou
  and Frank van Harmelen