Transcript Shaping the Future of the Web: Opportunities and Challenges

Intelligent Systems
Semantic Web and
Services
© Copyright 2010 Dieter Fensel and Mick Kerrigan
1
Where are we?
#
Title
1
Introduction
2
Propositional Logic
3
Predicate Logic
4
Reasoning
5
Search Methods
6
CommonKADS
7
Problem-Solving Methods
8
Planning
9
Software Agents
10
Rule Learning
11
Inductive Logic Programming
12
Formal Concept Analysis
13
Neural Networks
14
Semantic Web and Services
2
Agenda
•
•
•
Semantic Web - Data
•
Motivation
•
Technical Solution: URI, RDF, RDFS, OWL, SPARQL
•
Illustration by Larger Examples: KIM Browser Plugin, Disco Hyperdata Browser
•
Extensions: Linked Open Data
Semantic Web – Processes
•
Motivation
•
Technical Solution: Semantic Web Services, WSMO, WSML, SEE, WSMX
•
Illustration by Larger Examples: SWS Challenge, Virtual Travel Agency, WSMX
at work
•
Extensions: Mobile Services, Intelligent Cars, Intelligent Electricity Meters
Conclusions
3
3
SEMANTIC WEB - DATA
4
4
MOTIVATION
5
5
Limitations of the current Web
• The current Web has its limitations when it
comes to:
1. finding relevant information
2. extracting relevant information
3. combining and reusing information
6
Limitations of the current Web
Finding relevant information
• Finding information on the current Web is based on
keyword search
• Keyword search has a limited recall and precision due
to:
– Synonyms:
• e.g. Searching information about “Cars” will ignore Web pages that contain
the word “Automobiles” even though the information on these pages could
be relevant
– Homonyms:
• e.g. Searching information about “Jaguar” will bring up pages containing
information about both “Jaguar” (the car brand) and “Jaguar” (the animal)
even though the user is interested only in one of them
7
Limitations of the current Web
Finding relevant information
• Keyword search has a limited recall and precision due
also to:
– Spelling variants:
• e.g. “organize” in American English vs. “organise” in British English
– Spelling mistakes
– Multiple languages
• i.e. information about same topics in published on the Web on different
languages (English, German, Italian,…)
• Current search engines provide no means to specify the
relation between a resource and a term
– e.g. sell / buy
8
Limitations of the current Web
Extracting relevant information
•
•
One-fit-all automatic solution for extracting information from Web pages is
not possible due to different formats, different syntaxes
Even from a single Web page is difficult to extract the relevant information
Which book is
about the Web?
What is the price
of the book?
9
Limitations of the Traditional Web
Extracting relevant information
• Extracting information from current web sites can be
done using wrappers
WEB
HTML pages
Layout
Wrapper
extract
annotate
structure
Structured Data,
Databases,
XML
Structure
10
Limitations of the Traditional Web
Extracting relevant information
• The actual extraction of information from web sites is
specified using standards such as XSL Transformation
(XSLT) [1]
• Extracted information can be stored as structured data in
XML format or databases.
• However, using wrappers do not really scale because
the actual extraction of information depends again on the
web site format and layout
[1] http://www.w3.org/TR/xslt
11
Limitations of the Traditional Web
Combining and reusing information
• Tasks often require to combine data on the
Web
1. Searching for the same information in
different digital libraries
2. Information may come from different web
sites and needs to be combined
12
Limitations of the Traditional Web
Combining and reusing information
1. Searches for the same information in different digital
libraries
Example: I want travel from Innsbruck to Rome.
13
Limitations of the Traditional Web
Combining and reusing information
2. Information may come from different web sites and needs to
be combined
Example: I want to travel from Innsbruck to Rome where I want to stay in a
hotel and visit the city
14
How to improve current Web?
•
•
•
•
Increasing automatic linking among data
Increasing recall and precision in search
Increasing automation in data integration
Increasing automation in the service life cycle
• Adding semantics to data and services is the
solution!
15
TECHNICAL SOLUTIONS
16
16
Uniform Resource Identifier
• Uniform Resource Identifiers (URIs) are used to identify resources,
not just things that exists on the Web, e.g. Dieter Fensel, University
of Innsbruck
Taken from http://www.w3.org/TR/webarch/
17
Resource Description Framework (RDF)
•
The Resource Description Framework (RDF) provides a domain
independent data model
•
Resource (identified by URIs)
•
•
– Correspond to nodes in a graph
– E.g.:
http://www.w3.org/
http://example.org/#john
http://www.w3.org/1999/02/22-rdf-syntax-ns#Property
Properties (identified by URIs)
– Correspond to labels of edges in a graph
– Binary relation between two resources
– E.g.:
http://www.example.org/#hasName
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
Literals
– Concrete data values
– E.g.:
"John Smith", "1", "2006-03-07"
18
18
Resource Description Framework (RDF) –
Triple Data Model
• Triple data model:
<subject, predicate, object>
– Subject: Resource or blank node
– Predicate: Property
– Object: Resource, literal or blank node
• Example:
<ex:john, ex:father-of, ex:bill>
• Statement (or triple) as a logical formula P(x, y), where the binary
predicate P relates the object x to the object y.
• RDF offers only binary predicates (properties)
19
19
Resource Description Framework (RDF) –
Graph Model
• The triple data model can be represented as a graph
• Such graph is called in the Artificial Intelligence community a
semantic net
• Labeled, directed graphs
– Nodes: resources, literals
– Labels: properties
– Edges: statements
ex:john
ex:father-of
ex:bill
ex:father-of
ex:tom
20
20
RDF Schema (RDFS)
• RDF Schema (RDFS) is a language for capturing the
semantics of a domain, for example:
– In RDF:
<#john, rdf:type, #Student>
– What is a “#Student”?
• RDFS is a language for defining RDF types:
– Define classes:
• “#Student is a class”
– Relationships between classes:
• “#Student is a sub-class of #Person”
– Properties of classes:
• “#Person has a property hasName”
21
RDF Schema (RDFS)
• Classes:
<#Student, rdf:type, #rdfs:Class>
• Class hierarchies:
<#Student, rdfs:subClassOf, #Person>
• Properties:
<#hasName, rdf:type, rdf:Property>
• Property hierarchies:
<#hasMother, rdfs:subPropertyOf, #hasParent>
• Associating properties with classes (a):
– “The property #hasName only applies to #Person”
<#hasName, rdfs:domain, #Person>
• Associating properties with classes (b):
– “The type of the property #hasName is #xsd:string”
<#hasName, rdfs:range, xsd:string>
22
22
RDF Schema (RDFS) - Example
23
23
Web Ontology Language (OWL)
•
RDFS has a number of Limitations:
•
The Web Ontology Language (OWL) provides an ontology language, that is
a more expressive Vocabulary Definition Language for use with RDF
– Only binary relations
– Characteristics of Properties, e.g. inverse, transitive, symmetric
– Local range restrictions, e.g. for class Person, the property hasName has range
xsd:string
– Complex concept descriptions, e.g. Person is defined by Man and Woman
– Cardinality restrictions, e.g. a Person may have at most 1 name
– Disjointness axioms, e.g. nobody can be both a Man and a Woman
–
–
–
–
Class membership
Equivalance of classes
Consistency
Classification
24
OWL
•
OWL is layered into languages of different expressiveness
–
–
–
OWL Lite: Classification Hierarchies, Simple Constraints
OWL DL: Maximal expressiveness while maintaining tractability
OWL Full: Very high expressiveness, loses tractability, all syntactic freedom of RDF
•
More expressive means harder to reason with
•
Different Syntaxes:
–
–
–
RDF/XML (Recommended for Serialization)
N3 (Recommended for Human readable Fragments)
Abstract Syntax (Clear Human Readable Syntax)
lite
DL
Full
25
25
OWL – Example: The Wine Ontology
•
•
•
•
•
An Ontology describing wine domain
One of the most widely used examples for OWL and referenced by
W3C.
There is also a wine agent associated to this ontology that performs
OWL queries using a web-based ontological mark-up language. That is,
by combining a logical reasoner with an OWL ontology.
The agent's operation can be described in three parts: consulting the
ontology, performing queries and outputting results.
Available here: http://www.w3.org/TR/owl-guide/
26
OWL – Example: The Wine Ontology Schema
[http://mysite.verizon.net/jflynn12/VisioOWL/VisioOWL.htm]
27
SPARQL – Querying RDF
•
SPARQL
– RDF Query language
– Based on RDQL
– Uses SQL-like syntax
•
Example:
PREFIX uni: <http://example.org/uni/>
SELECT ?name
FROM <http://example.org/personal>
WHERE { ?s uni:name ?name.
?s rdf:type uni:lecturer }
28
SPARQL Queries
PREFIX uni: <http://example.org/uni/>
SELECT ?name
FROM <http://example.org/personal>
WHERE { ?s uni:name ?name. ?s rdf:type uni:lecturer }
•
•
•
•
•
•
•
PREFIX
– Prefix mechanism for abbreviating URIs
SELECT
– Identifies the variables to be returned in the query answer
– SELECT DISTINCT
– SELECT REDUCED
FROM
– Name of the graph to be queried
– FROM NAMED
WHERE
– Query pattern as a list of triple patterns
LIMIT
OFFSET
ORDER BY
29
SPARQL Example Query 1
“Return the full names of all people in the graph”
PREFIX vCard: <http://www.w3.org/2001/vcard-rdf/3.0#>
SELECT ?fullName
WHERE {?x vCard:FN ?fullName}
result:
fullName
=================
"John Smith"
"Mary Smith"
@prefix ex: <http://example.org/#> .
@prefix vcard: <http://www.w3.org/2001/vcard-rdf/3.0#> .
ex:john
vcard:FN "John Smith" ;
vcard:N [
vcard:Given "John" ;
vcard:Family "Smith" ] ;
ex:hasAge 32 ;
ex:marriedTo :mary .
ex:mary
vcard:FN "Mary Smith" ;
vcard:N [
vcard:Given "Mary" ;
vcard:Family "Smith" ] ;
ex:hasAge 29 .
30
SPARQL Example Query 2
“Return the relation between John and Mary”
PREFIX ex: <http://example.org/#>
SELECT ?p
WHERE {ex:john ?p ex:mary}
result:
p
=================
<http://example.org/#marriedTo>
@prefix ex: <http://example.org/#> .
@prefix vcard: <http://www.w3.org/2001/vcard-rdf/3.0#> .
ex:john
vcard:FN "John Smith" ;
vcard:N [
vcard:Given "John" ;
vcard:Family "Smith" ] ;
ex:hasAge 32 ;
ex:marriedTo :mary .
ex:mary
vcard:FN "Mary Smith" ;
vcard:N [
vcard:Given "Mary" ;
vcard:Family "Smith" ] ;
ex:hasAge 29 .
31
SPARQL Example Query 3
“Return the spouse of a person by the name of John Smith”
PREFIX vCard: <http://www.w3.org/2001/vcard-rdf/3.0#>
PREFIX ex: <http://example.org/#>
SELECT ?y
WHERE {?x vCard:FN "John Smith".
?x ex:marriedTo ?y}
result:
y
=================
<http://example.org/#mary>
@prefix ex: <http://example.org/#> .
@prefix vcard: <http://www.w3.org/2001/vcard-rdf/3.0#> .
ex:john
vcard:FN "John Smith" ;
vcard:N [
vcard:Given "John" ;
vcard:Family "Smith" ] ;
ex:hasAge 32 ;
ex:marriedTo :mary .
ex:mary
vcard:FN "Mary Smith" ;
vcard:N [
vcard:Given "Mary" ;
vcard:Family "Smith" ] ;
ex:hasAge 29 .
32
ILLUSTRATION BY LARGER
EXAMPLES
33
33
Illustration 1 – KIM Browser Plugin
• KIM Browser Plugin
Web content is annotated using
ontologies
Content can be searched and
browsed intelligently
Select one or more concepts
from the ontology…
… send the currently loaded
web page to the Annotation
Server
Annotated Content
34
34
Illustration 2 – Disco Hyperdata Browser
Dereferencable
URI
Disco Hyperdata Browser
navigating the Semantic Web as an
unbound set of data sources
35
35
EXTENSIONS
36
36
Extensions: Linked Open Data
•
Linked Data is a method for exposing and sharing connected data via
dereferenceable URI’s on the Web
–
–
–
–
•
Use URIs to identify things that you expose to the Web as resources
Use HTTP URIs so that people can locate and look up (dereference) these things
Provide useful information about the resource when its URI is dereferenced
Include links to other, related URIs in the exposed data as a means of improving
information discovery on the Web
Linked Open Data is an initiative to interlink open data sources
– Open: Publicly available data sets that are accessible to everyone
– Interlinked: Datasets have references to one another allowing them to be used
together
37
37
Extensions: Linked Open Data
38
38
Extensions: Linked Open Data - FOAF
•
Friend Of A Friend (FOAF) provides a way to create machine-readable
pages about:
– People
– The links between them
– The things they do and create
•
Anyone can publish a FOAF file on the web about themselves and this
data becomes part of the Web of Data
<foaf:Person>
<foaf:name>Dieter Fensel</foaf:name>
<foaf:homepage rdf:resource="http://www.fensel.com"/>
</foaf:Person>
•
FOAF is connected to many other data sets, including
– Data sets describing music and musicians (Audio Scrobbler, MusicBrainz)
– Data sets describing photographs and who took them (Flickr)
– Data sets describing places and their relationship (GeoNames)
39
39
Extensions: Linked Open Data - GeoNames
•
The GeoNames Ontology makes it possible to add geospatial semantic
information to the Web of Data
•
We can utilize GeoNames location within the FOAF profile
<foaf:Person>
<foaf:name>Dieter Fensel</foaf:name>
<foaf:homepage rdf:resource="http://www.fensel.com"/>
<foaf:based_near ” http://ws.geonames.org/rdf?geonameId=2775220"/>
</foaf:Person>
•
GeoNames is also linked to more datasets
– US Census Data
– Movie Database (Linked MDB)
– Extracted data from Wikipedia (DBpedia)
40
40
Extensions: Linked Open Data - DBpedia
•
DBpedia is a community effort to extract structured information from
Wikipedia and to make this information available on the Web
•
As our FOAF profile has been linked to GeoNames, and GeoNames is
linked to DBpedia, we can ask some interesting queries over the Web
of Data
– What is the population of the city in which Dieter Fensel lives?
=> 117916 people
– At which elevation does Dieter Fensel live?
=> 574m
– Who is the mayor of the city in which Dieter Fensel lives
=> Hilde Zach
41
41
SEMANTIC WEB - PROCESSES
42
42
MOTIVATION
43
43
Motivation
http://www.sti-innsbruck.at/dip-movie
44
Motivation
• The Web is moving from static data to dynamic
functionality
– Web services: a piece of software available over the
Internet, using standardized XML messaging systems
– Mashups: The compounding of two or more pieces of
web functionality to create powerful web applications
45
Motivation
46
Limitations of the current Web Processes
• Web services and mashups are limited by their syntactic
nature
• As the amount of services on the Web increases it will
be harder to find Web services in order to use them in
mashups
• The current amount of human effort required to build
applications is not sustainable at a Web scale
47
What is needed?
• Formal, machine processable descriptions of processes on
the Web that allows easy integration, configuration and
reuse
• Semantic support for finding, composing and executing
these processes and all the other related tasks
Solution: Combine Semantics and Web processes/services that
enables the automation of many of the currently human intensive tasks
around Web processes/services
48
TECHNICAL SOLUTIONS
49
49
Semantic Web Services
•
Brings the benefits of Semantics to the executable part of the Web
– Ontologies as data model
– Unambiguous definition of service functionality and external interface
•
Reduce human effort in integrating services in SOA
– Many tasks in the process of using Web services can be automated
•
Improve dynamism
– New services available for use as they appear
– Service Producers and Consumers don’t need to know of each others existence
•
Improve stability
– Service interfaces are not tightly integrated so even less impact from changes
– Services can be easily replaced if they are no longer available
– Failover possibilities are limited only by the number of available services
50
50
Semantic Web Services
•
Semantic Web Services are a layer on top of existing Web service
technologies and do not aim to replace them
•
Provide a formal description of services, while still being compliant with
existing and emerging technologies
•
Distinguish between a Web service (computational entity) and a service
(value provided by invocation)
•
Make Web services easier to:
–
–
–
–
Find
Compare
Compose
Invoke
51
51
Technical Overview
Conceptual Model for
SWS
Formal Language for WSMO
Execution Environment
Ontology & Rule Language
for the Semantic Web
For SWS
52
52
WSMO – Design Principles
Web Service versus Service
Strict Decoupling
of Modeling Elements
Ontology-Based
WSMO
Centrality of
Mediation
Ontological Role
Separation
Description versus Implementation
53
53
WSMO – Conceptual Model
Objectives that a client wants to
achieve by using Web Services
Formally specified
terminology used
by all other
components
Semantic description
of Web Services
• Capability (functional)
• Interfaces (usage)
Connectors between components
with mediation facilities for handling
heterogeneities
54
54
WSML – Language Family
Expressivity
WSML - Full
WSML - Rule
with
WSML - DL
f
without
WSML - Flight
WSML - Core
55
55
Semantic Execution Environment
Semantic Execution Environment
broker
Discovery
Ranking
Selection
Composition
Data Mediation
Process Mediation
Monitoring
vertical
Process
Execution
Lifting &
Lowering
Reasoning
Storage
base
56
56
Semantic Execution Environment - WSMX
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
57
57
ILLUSTRATION BY LARGER
EXAMPLES
58
58
Illustration 1: SWS Challenge
Receives a customer id
and returns a full
customer description
id
Purchase Order
cid
Purchase Order
Confirmation
openOrder
addItem*
closeOrder
Blue Company can
only send POs and
receive PO
company
has discovered
Confirmations
•
•
Blue
Moon company on the Web
Allows the
opening of a PO,
Blue company wishes to communicate with Moon
company
•
the specification of the items
to be purchased and the
process interoperability
issues
closing of the PO
Broker required to resolve data and
59
59
Illustration 2: Virtual Travel Agency
Rail
Services
Flight
Services
Hotel
Services
Car Hire
Services
60
60
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
61
61
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
Request to discoverWSMX Managment
Web services.
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
62
62
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
Service
Requesters
System Interface
...
Adapter n
Data and Communication Protocols Adapters
Adapter 2
Agent
acting on
behalf of
service
requester
Adapter 1
Back-End
Application
Goal expressed
WSMX Managment
in WSML is
sent to
WSMX System
InterfaceWSMX
WSMX Monitor
WSML Editor
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
63
63
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Com. M. implements
the interface to
receive WSML goals
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
Choreography Editor
Mediator Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
Service
Providers
Administration Framework Interface
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
64
64
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Com. M. informs
Core that Goal
Interface
Interface
has been received
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
65
65
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
Mediator Editor
Chor. wrapper
picks up event for
Chor. component
Service
Providers
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
66
66
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
Mediator Editor
Service
New choreography Providers
Instance is created
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
67
67
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
DM
Wrapper
Core is
PM
Choreography
Wrapper
Wrapper
notified
that choreography
instance Interface
has been Interface
Interface
created.
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
68
68
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
WSML Interface
goal is Interface
parsedResource
to
Communication
Manager
internal
format. Parser
Manager
Interface
Interface
Interface
Interface
Interface
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
RM
Wrapper
Interface
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
69
69
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Discovery
is
invoked Data
Process
Discovery Selector
Choreography
for parsed goal.
Mediator Mediator
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
70
70
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Data
Process
Invoker Receiver
Grounding
Resource Manager Interface
WSMO Objects
Non WSMO
Objects
Selector
Choreography
Discovery
may
Mediator Mediator
requires ontology
mediation.
Reasoner Interface
Reasoner
Web
Service 1
Web
Service 2
...
Web
Service p
Component
Wrapper
Interface
New
Component
71
71
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Process
Mediator
Choreography
Communication
Manager
Resource
Manager
Parser
Invoker Receiver
Grounding
After data mediation,
Data
DiscoveryDiscovery
Selectoriterates,
Mediator
if needed through
last steps until
result set is finished.
Resource Manager Interface
WSMO Objects
Non WSMO
Objects
Reasoner Interface
Reasoner
Web
Service 1
Web
Service 2
...
Web
Service p
Component
Wrapper
Interface
New
Component
72
72
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Data
Process
Selector
Selection
is invoked
Mediator
Mediator
Invoker Receiver
Grounding
Resource Manager Interface
WSMO Objects
Choreography
to relax result set to
finally one service.
Non WSMO
Objects
Reasoner Interface
Reasoner
Web
Service 1
Web
Service 2
...
Web
Service p
Component
Wrapper
Interface
New
Component
73
73
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
requester is checked
for next steps.
Invoker Receiver
Grounding
Resource Manager Interface
WSMO Objects
Process
Choreography
Choreography
Mediator
instance for goal
Non WSMO
Objects
Reasoner Interface
Reasoner
Web
Service 1
Web
Service 2
...
Web
Service p
Component
Wrapper
Interface
New
Component
74
74
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
System Interface
Adapter 2
...
Adapter n
Data and Communication Protocols Adapters
Adapter 1
Agent
acting on
behalf of
service
requester
WSML Editor
WSMX
Service
Requesters
Back-End
Application
WSMX Monitor
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Result is returned
to Com. Man.Resource
to be
Communication
forwarded to Manager
the
Manager
service requester.
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
75
75
Illustration 3: WSMX At Work
WSMT – Web Services Modelling Toolkit
WSMX Managment
WSMX
Service
Requesters
System Interface
...
Adapter n
Data and Communication Protocols Adapters
Adapter 2
Agent
acting on
behalf of
service
requester
Adapter 1
Back-End
Application
WSMX Monitor
WSML Editor
Set of Web Service
descriptions
expressed in WSML
sent to adapter.
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
76
76
Illustration 3: WSMX At Work
Set of Web Service
descriptions expressed
in requester’s own
WSMX Managment
format returned to
goal requester.
WSMX
Service
Requesters
System Interface
...
Adapter n
Data and Communication Protocols Adapters
Adapter 2
Agent
acting on
behalf of
service
requester
Adapter 1
Back-End
Application
WSMT – Web Services Modelling Toolkit
WSMX Monitor
WSML Editor
Choreography Editor
Mediator Editor
Service
Providers
Administration Framework Interface
WSMX Manager
WSMX Manager Core
CM
Wrapper
RM
Wrapper
Parser
Wrapper
Discovery
Wrapper
Selector
Wrapper
DM
Wrapper
PM
Wrapper
Choreography
Wrapper
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Interface
Communication
Manager
Resource
Manager
Parser
Discovery
Selector
Data
Mediator
Process
Mediator
Choreography
Invoker Receiver
Web
Service 2
...
Web
Service p
Grounding
Resource Manager Interface
WSMO Objects
Web
Service 1
Non WSMO
Objects
Reasoner Interface
Reasoner
Component
Wrapper
Interface
New
Component
77
77
EXTENSIONS
78
78
Extensions: Mobile Services
79
Extensions: Mobile Services
• Extending the mobile and sensors networks with Semantic
technologies, Semantic Web will enable:
– Interoperability at the level of sensors data and protocols
– More precise search for mobile capabilities and sensors with desired capability
From: http://www.opengeospatial.org/projects/groups/sensorweb
80
Extensions: Intelligent Cars
81
Extensions: Intelligent Cars
•
A key aspect of future
cars will be intelligence
–
–
–
–
•
From: http://www.nff.tu-bs.de/index.php?id=464&L=1
Real-time data collection
Car-to-X communication
Interaction Systems
Driver Assistance
Semantic Technologies
can be used to add this
intelligence through:
– Machine awareness of
context (Spatio-temporal
concerns, mood, etc..)
– Management of large
volumes of real-time data
– Enabling interoperability
between systems
82
Extensions: A Smarter Electricity Grid
83
Extensions: A Smarter Electricity Grid
•
Managing increasingly dispersed energy resources is crucial to ensure
efficient electricity consumption, for example
– Wind farms
– Solar panels
•
Grid operators cannot be sure at any given time:
– Which electricity generators are connected
– If they are operational or not
– How much power they are outputting
•
Semantic technologies can be used to enable “self-describing
networks”
– Each member of the network autonomously publishes semantic data about itself
– Enables more efficient automated grid management technologies
•
Ultimately semantic technologies can provide a “Smart Electricity Grid”
84
SUMMARY
85
85
Summary
•
The Semantic Web provides a mechanism for
– Representing knowledge on the Web
– Annotating data on the Web
– Annotating services on the Web
•
•
•
•
•
•
•
Everything is identified by a URI
RDF to assert relations between resources
RDFS and OWL to make statements about types
SPARQL to query RDF data
WSMO as a conceptual model
WSML for describing services at different levels of expressivity
WSMX as a Semantic Execution Environment for bringing requesters
and providers together
86
86
REFERENCES
87
87
References
•
Mandatory reading:
–
–
•
T. Berners-Lee, J. Hendler, O. Lassila. The Semantic Web, Scientific American, 2001.
Dieter Fensel, Holger Lausen, Axel Polleres, Jos de Bruijn, Michael Stollberg, Dumitru
Roman, John Domingue, Enabling Semantic Web Services: The Web Service Modeling
Ontology, Springer-Verlag, 2007
Further reading:
–
–
–
–
–
–
–
Dieter Fensel, Mick Kerrigan, Michal Zaremba (Eds.), Implementing Semantic Web Services:
The SESA Framework. Springer-Verlag, 2008.
Jos de Bruijn, Dieter Fensel, Mick Kerrigan, Uwe Keller, Holger Lausen, and James
Scicluna: Modeling Semantic Web Services, Springer-Verlag, 2008
D. Fensel. Ontologies: A Silver Bullet for Knowledge Management and Electronic Commerce,
2nd Edition, Springer 2003.
G. Antoniou and F. van Harmelen. A Semantic Web Primer, (2nd edition), The MIT Press
2008.
H. Stuckenschmidt and F. van Harmelen. Information Sharing on the Semantic Web,
Springer 2004.
T. Berners-Lee. Weaving the Web, HarperCollins 2000
T.R. Gruber, Toward principles for the design of ontologies used or knowledge sharing? , Int.
J. Hum.-Comput. Stud., vol. 43, no. 5-6,1995
88
References
–
–
–
David Martin, et al., OWL-S: Semantic Markup for Web Services, W3C Member Submission
22 November 2004, http://www.w3.org/Submission/OWL-S.
Joel Farrell and Holger Lausen, Semantic Annotations for WSDL and XML Schema, W3C
Recommendation 28 August 2007, http://www.w3.org/TR/sawsdl
Rama Akkiraju et al., Web Service Semantics - WSDL-S, W3C Member Submission 7
November 2005, http://www.w3.org/Submission/WSDL-S
–
Steve Battle et al., Semantic Web Services Framework (SWSF), W3C Member Submission
9 September 2005, http://www.w3.org/Submission/SWSF
–
Semantic Web Primer: http://www.ics.forth.gr/isl/swprimer/
–
RDF Primer: http://www.w3.org/TR/REC-rdf-syntax/
–
RDF Schema: http://www.w3.org/TR/rdf-schema/
–
OWL Guide: http://www.w3.org/TR/owl-guide/
–
RDF SPARQL Protocol: http://www.w3.org/TR/rdf-sparql-protocol/
–
Linked Open Data: http://linkeddata.org/
–
Linked Open Data Tutorial: http://www4.wiwiss.fu-berlin.de/bizer/pub/LinkedDataTutorial/
–
WSMO: http://www.wsmo.org/TR/d2/
–
WSML: http://www.wsmo.org/TR/d16/d16.1/
–
WSMO/WSML Tutorials: http://wiki.sti2.at/index.php?title=WSMT_Tutorials
89
References
•
Wikipedia links:
– URI: http://en.wikipedia.org/wiki/URI
– RDF; http://en.wikipedia.org/wiki/Resource_Description_Framework
– RDFS: http://en.wikipedia.org/wiki/RDFS
– SPARQL: http://en.wikipedia.org/wiki/SPARQL
– WSMO: http://en.wikipedia.org/wiki/WSMO
– WSML: http://en.wikipedia.org/wiki/Web_Services_Modeling_Language
90
Exam Preparation
•
•
•
Exam will take place on the DD.MM.YYYY, HH:MM in room X.
Exam time is 90 minutes
The material for exam are the slide sets:
Title
Introduction
Propositional Logic
Predicate Logic
Theorem Proving, Description Logics and Logic Programming
Search Methods
CommonKADS
Problem Solving Methods
Planning
Agents
Rule Learning
Inductive Logic Programming
Semantic Web and Exam Preparation
91
91
Questions?
92
92