Mobile Web Services RDF and RDF Schema for ontology specification Presenter: Chen Jen

Outline Introduction RDF discussion Beyond RDF Schema Reference

Introduction

RDF discussion

Beyond RDF Schema

Reference

Introduction Metadata decide data’s importance by self No require human or computer to determine its relevance Metadata need accepted vocabulary

Metadata decide data’s importance by self

No require human or computer to determine its relevance

Metadata need accepted vocabulary

Introduction Resource Description Framework (RDF) was developed Uniform Resource Identifiers (URIs) identify resources Assertion format is based on XML notation

Resource Description Framework (RDF) was developed

Uniform Resource Identifiers (URIs) identify resources

Assertion format is based on XML notation

Introduction Resource assertion has three objects Resource itself Property name Statement Three objects is the same in RDF Subject Predicate object

Resource assertion has three objects

Resource itself

Property name

Statement

Three objects is the same in RDF

Subject

Predicate

object

RDF discussion RDF application RDF graph models RDF XML syntax RDF vocabularies and schemas RDF schema language

RDF application

RDF graph models

RDF XML syntax

RDF vocabularies and schemas

RDF schema language

RDF applications Mobile terminal capabilities Adapt their content for each terminal Screen size, screen resolution, color support etc. Indicate relative degrees of preference Client prefers markup quality

Mobile terminal capabilities

Adapt their content for each terminal

Screen size, screen resolution, color support etc.

Indicate relative degrees of preference

Client prefers markup quality

RDF applications User privacy preferences Network access constraints Specify on WLAN or cellular network

User privacy preferences

Network access constraints

Specify on WLAN or cellular network

RDF graph models (1) (2) (3) (4)

RDF graph models Resource = Source node (1) Property name = Arc (2) Property value = Final node (3) Structured information resource = Blank node (4)

Resource = Source node (1)

Property name = Arc (2)

Property value = Final node (3)

Structured information resource = Blank node (4)

RDF XML syntax

RDF XML syntax < rdf:RDF > = RDF resource representation XML namespace xmlns:rdf for W3C RDF specific term xmlns:prf for WAP Forum’s UAProf term Term prefixed with rdf correspond W3C URI prf correspond WAP Forum URI

< rdf:RDF > = RDF resource representation

XML namespace

xmlns:rdf for W3C RDF specific term

xmlns:prf for WAP Forum’s UAProf term

Term prefixed with

rdf correspond W3C URI

prf correspond WAP Forum URI

RDF XML syntax < Description > is Describe resource Likeness of nested element

< Description > is

Describe resource

Likeness of nested element

RDF XML syntax

RDF XML syntax Domain is defined by another associated resource URI < comment > replace RDF <value> DTD (Document Type Definition) can be used in XML

Domain is defined by another associated resource URI

< comment > replace RDF <value>

DTD (Document Type Definition) can be used in XML

RDF XML syntax <Bag> = unordered group of resources rdf:Bag <Sequence> = ordered group rdf:Seq <Alternative> = alternative values rdf:Alt < rdf:li > = separate line item

<Bag> = unordered group of resources

rdf:Bag

<Sequence> = ordered group

rdf:Seq

<Alternative> = alternative values

rdf:Alt

< rdf:li > = separate line item

RDF vocabularies and schemas Vocabulary = collection of resources and properties PDA, Phone, GPS, etc. RDF schema is used by object-oriented Namespace rdfs = RDF schema vocabulary

Vocabulary = collection of resources and properties

PDA, Phone, GPS, etc.

RDF schema is used by object-oriented

Namespace rdfs = RDF schema vocabulary

RDF schema language

RDF schema language - RDFS class Class = Resource rdf:type property = rdf:Class Rdfs:subClassOf = parent resource MobileTerminal is class Phone, PDA are subclasses

Class = Resource

rdf:type property = rdf:Class

Rdfs:subClassOf = parent resource

MobileTerminal is class

Phone, PDA are subclasses

RDF schema language – RDFS properties and property constraints rdf:type value is rdf:Property domain constrain property to be associated with certain resources range define that property can have value rdfs:subProperyOf property is organized. GIFcapable is sub-property of UAProf’s ImageCapable property

rdf:type value is rdf:Property

domain constrain property to be associated with certain resources

range define that property can have value

rdfs:subProperyOf property is organized.

GIFcapable is sub-property of UAProf’s ImageCapable property

RDF schema language – Component design with RDFS Property-centric specification has many benefits Independently of class No need to redefine Object-oriented programming language No include all applicable properties

Property-centric specification has many benefits

Independently of class

No need to redefine

Object-oriented programming language

No include all applicable properties

Beyond RDF Schema The Web Ontology Language (OWL) Defense Advanced Research Projects Agency (DARPA) DARPA Agent Markup Language (DAML) Facilitate the concept of the Semantic Ontology Inference Layer (OIL) Knowledge-representation research

The Web Ontology Language (OWL)

Defense Advanced Research Projects Agency (DARPA)

DARPA Agent Markup Language (DAML)

Facilitate the concept of the Semantic

Ontology Inference Layer (OIL)

Knowledge-representation research

Beyond RDF Schema OWL is published as W3C Need of different community Different levels of ontology sophistication OWL Description Logics (DL) Require strict type OWL Full No have any limitation

OWL is published as W3C

Need of different community

Different levels of ontology sophistication

OWL Description Logics (DL)

Require strict type

OWL Full

No have any limitation

Beyond RDF Schema OWL-based Web Service Ontology (OWL-S) Automation of services on the Semantic Web Core set of markup language construct Automation of task Web service discovery Invocation Composition and interoperation Execution monitoring

OWL-based Web Service Ontology (OWL-S)

Automation of services on the Semantic Web

Core set of markup language construct

Automation of task

Web service discovery

Invocation

Composition and interoperation

Execution monitoring

Beyond RDF Schema Web service discovery Automatic offer specific services Web service invocation Web service function to invoke Interoperation and composition Multiple Web services combine a composite service

Web service discovery

Automatic offer specific services

Web service invocation

Web service function to invoke

Interoperation and composition

Multiple Web services combine a composite service

Beyond RDF Schema Monitoring track Aware and progress of their request

Monitoring track

Aware and progress of their request

Reference Ariel Pashtan, Mobile Web Service. Page 138 ~153.

Ariel Pashtan, Mobile Web Service. Page 138 ~153.