SemanticdddddddddddddddddddddddddddddddddeeeWeb.ppt

derffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderffrefefefefderf

1. State of the Art in
Semantic Web standards
and technologies
Andreas Duscher

2. State of the Art in
Semantic Web Standards
and Technologies
 General Overview
 RDF / RDF Schema
 OWL
 OWL-S
 Final words

3. Today´s web
It is designed for human consumption
Information retrieval is mainly supported by keyword-based
search engines
Some problems with information retrieval:
High recall, low precision
Low or no recall
Results are highly sensitive to vocabulary
Web content is not machine-proccessable
„I am a professor of computer science.“
-- or --
„I am a professor of computer science, you may
think. Well….“

4. Semantic Web Vision
„The Semantic Web provides a common framework that
allows data to be shared and reused across application,
enterprise, and community boundaries.“
[http://www.w3.org/2001/sw/]
Problem „Business-to-consumer
electronic commerce“
• Manually retrieving the best offers from
different online-shops is too time-consuming.
• Tools for shoping are available in the form of
shop bots.
• For every online shop a wrapper is needed
(information is extracted through text analysis).
Vision „Business-to-consumer
electronic commerce“
• The user asks a autonomously acting piece
of software for a certain product.
• The software retrieves all offers and
compares them with the user‘s preferences.
• If needed the sofware negotiates with the
shop for a special discount or tries to get a
trusted rating for the shop.

5. Semantic Web Technologies
Ontologies
An ontology describes formally a domain of
discourse.
It is a finite list of terms and the relationship
between these terms.
Types of relationship: subclass hierarchy,
properties, value restrictions, logical relationships
between objects
„In the context of web an ontology provide a
shared understanding of a domain.“

6. Semantic Web Technologies
Logic
„A discipline that studies the principles of reasoning.“
Automated reasoners allow to draw conclusions from
given knowledge, make implicit knowledge explicit.
prof(X) -> faculty(X)
faculty(X) -> staff(X)
prof(michael)

7. Semantic Web Technologies
Logic
„A discipline that studies the principles of reasoning.“
Automated reasoners allow to draw conclusions from
given knowledge, make implicit knowledge explicit.
prof(X) -> faculty(X)
faculty(X) -> staff(X)
prof(michael)
faculty(michael)
staff(michael)
prof(X) -> staff(X)
This example involves knowledge typically found in
ontologies.

8. Semantic Web Technologies
Agents
Agents are pieces of software that work autonomously
and proactively.
A personal agent would recieive some task and
preferences from the user, communicate with other
agents, compare information and select certain
choices.
Web services
collection of protocols and standard for exchanging
data between various applications

9. Semantic Web Technologies
How it fits together?
Onotologies can be used to represent knowledge, interpret
the retrieved information and communicate with other
agents.
Logic can be used for processing the retrieved information
and for drawing conclusions.
Agent / Web service technologies allow the communication
between different systems and the composition of
complexer services from simple ones.

10. Semantic Web Technologies
How it fits together?
Onotologies can be used to represent knowledge, interpret
the retrieved information and communicate with other
agents.
=> RDF / RDF Schema / OWL
Logic can be used for processing the retrieved information
and for drawing conclusions.
=> Defining an OWL-based language is in progress!
Agent / Web service technologies allow the communication
between different systems and the composition of
complexer services from simpler ones.
=> OWL-S

11. RDF Motivation
The Resource Description Framework (RDF) is a
language for representing resources in the World Wide
Web.
RDF is intended for situations in which this information
needs to be processed by applications, rather than being
only displayed to people.
RDF is based on the idea of identifying things using Web
identifiers (URIs).

12. RDF Basic Concepts
the thing the statement describes (the web page`s URL)
a specific property of the thing (e.g. creator)
the concrete message the statement wants to give,
in other words the value of the property (John Smith)
RDF basic ideas
Things being described have properties, which have values
Resources can be described by making statements
(similar to the above example)
http://www.example.org/index.html has a creator whose value is John Smith
Example
„Imagine trying to state that someone named John Smith created a particular
Web page.“

13. RDF Basic Concepts
RDF terminology
the part that identifies the thing the statemant is about is called subject
the part that identifies the property is called predicate
the part that identifies the value of the property is called object
Subject Object
Predicate

14. RDF Basic Concepts
RDF terminology
the part that identifies the thing the statemant is about is called subject
the part that identifies the property is called predicate
the part that identifies the value of the property is called object
Subject Object
Predicate
http://www.example.org/index.html has a creator whose value is John Smith
the subject is the URL „http://www.example.org/index.html“
the predicate is the word „creator“
the object is the name „John Smith“

15. RDF Basic Concepts
To make these statements machine-proccessable
two things are needed:
a system of machine-processable identifiers (for subjects, predicates
and objects) without any possibilty of confusion between similar looking
identifiers

16. RDF Basic Concepts
To make these statements machine-proccessable
two things are needed:
a system of machine-processable identifiers (for subjects, predicates
and objects) without any possibilty of confusion between similar looking
identifiers
a machine-processable language for representing these statements and
exchanging them between machines

17. RDF Basic Concepts
To make these statements machine-proccessable
two things are needed:
a system of machine-processable identifiers (for subjects, predicates
and objects) without any possibilty of confusion between similar looking
identifiers
a machine-processable language for representing these statements and
exchanging them between machines
Uniform Resource Identifiers (URI) allow to identify and uniquely
name things - even if they have no network-accessible location.

18. RDF Basic Concepts
To make these statements machine-proccessable
two things are needed:
a system of machine-processable identifiers (for subjects, predicates
and objects) without any possibilty of confusion between similar looking
identifiers
a machine-processable language for representing these statements and
exchanging them between machines
RDF defines a XML markup language, named RDF/XML, which
allows to represent RDF statements.
Uniform Resource Identifiers (URI) allow to identify and uniquely
name things - even if they have no network-accessible location.

19. RDF Model
As mentioned:
RDF makes statements about resources
Each statement consists of a subject, a predicate and an object
http://www.example.org/index.html has a creator whose value is John Smith
http://www.example.org/staffid/5232
http://purl.org/dc/elements/1.1/creator
http://www.example.org/index.html

20. RDF Model
As mentioned:
RDF makes statements about resources
Each statement consists of a subject, a predicate and an object
http://www.example.org/index.html has a creator whose value is John Smith
http://www.example.org/staffid/5232
http://purl.org/dc/elements/1.1/creator
http://www.example.org/index.html
subject
object
predicate

21. RDF Model
Conclusion
RDF documents are „nodes-and-arcs diagrams
interpreted as statements about things identified
by URIrefs“.
So subjects, predicates and objects can be
identified by URIrefs.

22. RDF Syntax
http://www.example.org/terms/creation-date
http://www.example.org/index.html
August 16, 1999
<?xml version="1.0"?>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:exterms="http://www.example.org/terms/">

<rdf:Description rdf:about="http://www.example.org/index.html">
<exterms:creation-date>August 16, 1999</exterms:creation-
date>
</rdf:Description>
</rdf:RDF>

23. RDF Syntax
http://www.example.org/terms/creation-date
August 16, 1999
<?xml version="1.0"?>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:dc="http://purl.org/dc/elements/1.1/"
xmlns:exterms="http://www.example.org/terms/">

<rdf:Description rdf:about="http://www.example.org/index.html">
<exterms:creation-date>August 16, 1999</exterms:creation-date>
<dc:creator rdf:resource="http://www.example.org/staffid/85740"/>
</rdf:Description>
</rdf:RDF>
http://www.example.org/staffid/4252
http://www.example.org/index.html
http://purl.org/dc/elements/1.1/creator

24. RDF Syntax
Abbreviating and Organizing RDF URIrefs
<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf=http://www.w3.org/1999/02/22-rdf-syntax-ns#
xmlns:exterms="http://www.example.com/terms/">
<rdf:Description rdf:ID="item10245">
<exterms:model rdf:datatype="&xsd;string">Overnighter</exterms:model>
<exterms:sleeps rdf:datatype="&xsd;integer">2</exterms:sleeps>
<exterms:weight rdf:datatype="&xsd;decimal">2.4</exterms:weight>
<exterms:packedSize rdf:datatype="&xsd;integer">784</exterms:packedSize>
</rdf:Description>
 rdf:about and rdf:ID are strictly speaking the same.
rdf:about is often used for talking about resources that have been defined
elsewhere.
 The value of rdf:ID can only appear once in a document.
 The fragment identifier item10245 will be interpreted relative to a base URI.

25. RDF Syntax
Typing in RDF
<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf=http://www.w3.org/1999/02/22-rdf-syntax-ns#
xmlns:exterms="http://www.example.com/terms/">
<rdf:Description rdf:ID="item10245">
<rdf:type rdf:resource="http://www.example.com/terms/Tent"/>
<exterms:model rdf:datatype="&xsd;string">Overnighter</exterms:model>
<exterms:sleeps rdf:datatype="&xsd;integer">2</exterms:sleeps>
…
</rdf:Description>
RDF allows to classify resources with the special attribute rdf:type.
The resource item10245 is called a tpyed node.
It is similar to the programming language concept of objects and classes
=> RDF Schema (RDFS)

26. RDF Syntax
Typing in RDF (abbreviated form)
<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf=http://www.w3.org/1999/02/22-rdf-syntax-ns#
xmlns:exterms="http://www.example.com/terms/">
<exterms:Tent rdf:ID="item10245">
<exterms:model rdf:datatype="&xsd;string">Overnighter</exterms:model>
<exterms:sleeps rdf:datatype="&xsd;integer">2</exterms:sleeps>
…
</exterms:Tent>
RDF allows to classify resources with the special attribute rdf:type.
The resource item10245 is called a tpyed node.
It is similar to the programming language concept of objects and classes
=> RDF Schema (RDFS)

27. RDFS Basics
What it is not
RDF Schema does not make any assumptions about any
application domain, nor does it define the semantics.
What it is
RDF Schema provides a vocabulary to describe classes of
things and/or resources.
Vocabulary descriptions written in RDF Schema language
are legal RDF graphs.
It is up to the user to devolpe a RDF Schema (RDFS) for
the needed application domain.

28. RDFS Basics
Own namespace http://www.w3.org/2000/01/rdf-schema#
Core classes

rdfs:Resource, the class of all resouces

rdfs:Class, the class of all classes

rdf:Property, the class of all properties
Properties can be used to characterize concrete classes
In RDF Schema, a class is any resource having an rdf:type
property whose value is the resource rdfs:Class.

29. RDFS Basics
Core properties

rdf:type, relates a resource to its class
So the resource is an instance of the class

rdfs:subClassOf, relates a class to one of its superclasses

rdfs:subPropertyOf, relates a property to one of its superproperties
The above properties are instances of the class
rdf:Property. Own properties can be defined by assigning
the type rdf:Property to any kind of resource.

30. RDFS Example (Classes)
<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xml:base="http://example.org/schemas/vehicles">
<rdf:Description rdf:ID="MotorVehicle">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-chema#Class"/>
</rdf:Description>
<rdf:Description rdf:ID="PassengerVehicle">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdf:Description>
<rdf:Description rdf:ID="Truck">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdf:Description>
<rdf:Description rdf:ID="Van">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdf:Description>
<rdf:Description rdf:ID="MiniVan">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
<rdfs:subClassOf rdf:resource="#Van"/>
<rdfs:subClassOf rdf:resource="#PassengerVehicle"/>
</rdf:Description>
</rdf:RDF>

31. RDFS Example (Classes)
<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xml:base="http://example.org/schemas/vehicles">
<rdf:Description rdf:ID="MotorVehicle">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-chema#Class"/>
</rdf:Description>
<rdf:Description rdf:ID="PassengerVehicle">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdf:Description>
<rdf:Description rdf:ID="Truck">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdf:Description>
<rdf:Description rdf:ID="Van">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdf:Description>
<rdf:Description rdf:ID="MiniVan">
<rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
<rdfs:subClassOf rdf:resource="#Van"/>
<rdfs:subClassOf rdf:resource="#PassengerVehicle"/>
</rdf:Description>
</rdf:RDF>
resource with an unique id
property „rdf:type“
that defines this
resource as „Class“
property „rfds:subClassOf“ with
a resource as value, in this
case a formerly defined class

32. RDFS Example (Classes)
<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xml:base="http://example.org/schemas/vehicles">
<rdfs:Class rdf:ID="MotorVehicle"/>
<rdfs:Class rdf:ID="PassengerVehicle">
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdfs:Class>
<rdfs:Class rdf:ID="Truck">
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdfs:Class>
<rdfs:Class rdf:ID="Van">
<rdfs:subClassOf rdf:resource="#MotorVehicle"/>
</rdfs:Class>
<rdfs:Class rdf:ID="MiniVan">
<rdfs:subClassOf rdf:resource="#Van"/>
<rdfs:subClassOf rdf:resource="#PassengerVehicle"/>
</rdfs:Class>
</rdf:RDF>
Abbreviated form
The value of the
property „rdf:type“
can be used for
naming the whole
resource.

33. RDFS Example (Properties)
<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
xml:base="http://example.org/schemas/vehicles">
…
<rdf:Property rdf:ID="registeredTo">
<rdfs:domain rdf:resource="#MotorVehicle"/>
<rdfs:range rdf:resource="#Person"/>
</rdf:Property>
<rdf:Property rdf:ID="rearSeatLegRoom">
<rdfs:domain rdf:resource="#PassengerVehicle"/>
<rdfs:range rdf:resource="&xsd;integer"/>
</rdf:Property>
<rdfs:Class rdf:ID="Person"/>
</rdf:RDF>
„rdfs:range“ indicates,
that the values of that
property are instances of a
certain class
„rdfs:domain“ indicates,
that the values of the
particular property applies
to a designated class

34. RDFS Example (Instances)
<?xml version="1.0"?> <!DOCTYPE rdf:RDF [<!ENTITY xsd
"http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:ex="http://example.org/schemas/vehicles#"
xml:base="http://example.org/things">
<ex:PassengerVehicle rdf:ID="johnSmithsCar">
<ex:registeredTo rdf:resource="http://www.example.org/staffid/85740"/>
<ex:rearSeatLegRoom rdf:datatype="&xsd;integer">
127
</ex:rearSeatLegRoom>
</ex:PassengerVehicle>
</rdf:RDF>
an instance of the class
„PassengerVehicle“
the defined properties that
can be applied to this class

35. RDF / RDFS Conclusion
Expressivity of RDF and RDF Schema is limited
Local scope of properties
Disjointness of classes
Boolean combination of classes
Cardiniality restrictions
Special characteristics of properties
Need for standardized ontology language
that builds upon existing concepts of RDF / RDFS
=> OWL Web Ontology Language

36. OWL Hierarchy
rdfs:Resource
rdfs:Class rdf:Property
owl:Class owl:ObjectProperty owl:DatatypeProperty

37. OWL Syntax
Class elements
Classes are defined using owl:Class
<owl:Class rdf:ID=“associateProfessor“>
<rdfs:subClassOf rdf:resource=“#academicStaffMember“ />
</owl:Class>
Disjoint classes
<owl:Class rdf:about=“#associateProfessor“>
<owl:disjointWith rdf:resource=“#professor“ />
<owl:disjointWith rdf:resource=“#assistantprofessor“ />
</owl:Class>
Equivalence of classes
<owl:Class rdf:ID=“faculty“>
<owl:equivalentClass rdf:resource=“#academicStaffMember“/>
</owl:Class>

38. OWL Syntax
Property elements
Datatype properties relate objects to datatype values
<owl:DatatypeProperty rdf:ID=“age“>
<rdfs:range rdf:resource=“http://www.w3.org/2001/XMLSchema
#nonNegativeInteger“ />
</owl:Class>
Object properties relate objects to other objects
<owl:ObjectProperty rdf:ID=“isTaughtBy“>
<rdfs:domain rdf:resource=“#course“/>
<rdfs:range rdf:resource=“#academicStaffMember“/>
</owl:Class>
<owl:ObjectProperty rdf:ID=“teaches“>
<rdfs:domain rdf:resource=“#academicStaffMember“/>
<rdfs:range rdf:resource=“#course“/>
<owl:inverseOf rdf:resource=“#isTaughtBy“/>
</owl:Class>

39. OWL Syntax
Property restrictions
Allow to specify constraints on classes and properties
<owl:Class about:ID=“#firstYearCourse“>
<rdfs:subClassOf>
<owl:Restriction>
<owl:onProperty rdf:resource=“#isTaughtBy“/>
<owl:allValuesFrom rdf:resource=“#Professor“/>
</owl:Restriction>
</rdfs:subClassOf>
</owl:Class>
<owl:Class about:ID=“#course“>
<rdfs:subClassOf>
<owl:Restriction>
<owl:onProperty rdf:resource=“#isTaughtBy“/>
<owl:minCardinality
rdf:datatype=“#&xsd;nonNegativeInteger“/>
</owl:Restriction>
</rdfs:subClassOf>
</owl:Class>

40. Web Services and the
Semantic Web
The Semantic Web should enable users to
locate, select, employ, compose, and monitor
Web-based services automatically.
Computer-interpretable description of the
service is needed.
OWL-S defines an ontology for describing
web services.

41. Web Services and the
Semantic Web
What does the service
provide?
ServiceProfile
A profile is used for advertizing the
service.
How is it used?
ServiceModel
A model describes how a service
works.
How to interact with it?
ServiceGrounding
A grounding provides the needed
details about transport protocols.

42. Web Services and the
Semantic Web (ServiceProfile)
<owl:Class rdf:ID="Profile">
<rdfs:label>Profile</rdfs:label>
<rdfs:subClassOf rdf:resource="&service;#ServiceProfile" />
<rdfs:comment> Definition of Profile </rdfs:comment>
</owl:Class>
<owl:ObjectProperty rdf:ID="hasInput">
<rdfs:subPropertyOf rdf:resource="#hasParameter"/>
<rdfs:range rdf:resource="&process;#Input"/>
</owl:ObjectProperty>

43. Web Services and the
Semantic Web (ServiceModel)

44. Web Services and the
Semantic Web (ServiceModel)
<owl:Class rdf:ID="SimpleProcess">
<rdfs:subClassOf rdf:resource="#Process"/>
<owl:disjointWith
rdf:resource="#AtomicProcess"/>
</owl:Class>
<owl:ObjectProperty rdf:ID="realizedBy">
<rdfs:domain rdf:resource="#SimpleProcess"/>
<rdfs:range rdf:resource="#AtomicProcess"/>
<owl:inverseOf rdf:resource="#realizes"/>
</owl:ObjectProperty>
<owl:ObjectProperty rdf:ID="realizes">
<rdfs:domain rdf:resource="#AtomicProcess"/>
<rdfs:range rdf:resource="#SimpleProcess"/>
<owl:inverseOf rdf:resource="#realizedBy"/>
</owl:ObjectProperty>

45. Conclusion
Today‘s web and its problems
A vision for a possible semantic web application
Overview of important standards
RDF / RDF Schema
OWL
OWL-S
The basic technologies exist but
- standards have to mature and
- more practical problems have to be solved
(tool support, ontology matching, …)

46. Bibliography
D. Martin et al., „OWL-S Semantic Markup for Web Services“
http://www.daml.org/services/owl-s/1.1/overview/
F. Manola and E. Miller, eds. „RDF Primer“, February 10, 2004.
http://www.w3.org/TR/rdf-primer/
M. Smith et al., „OWL Web Ontology Language Guide“,
http://www.w3.org/TR/owl-guide/
G. Antoniou, F. van Harmelen, „A Semantic Web Primer“, MIT
Press, London, England, 2004.