© 2001 DFKI GmbH -1- OntoViz Tab; XML Tab; RDF Backend; Flora Query Tab; OIL Support;...

transcript

OntoViz Tab;XML Tab; RDF Backend;

Flora Query Tab; OIL Support;Protégé-related Projects at DFKI

Michael Sintek

SMI & DFKI GmbH Kaiserslautern

http://www.dfki.uni-kl.de/~sintek/

sintek@dfki.de

5th Intl. Protégé WorkshopNewcastle, 16-18 July, 2001

Overview

• OntoViz Tab: ontology visualization

• XML Tab: importing and exporting XML data

• RDF Backend

• Flora Query Tab: querying with F-Logic

• OIL Support

• Protégé-related Projects at DFKI

The OntoViz Tab

Visualization ofProtégé-2000 Ontologies

OntoViz ...

• is a tab for visualizing Protégé-2000 ontologies

• can also be used to visualize ontology parts and

instances

• can display slots and slot edges

• is highly configurable, e.g.:• specify vicinity of classes/instances via “closure operators”

like subclasses, superclasses, reachable frames, ...

• colors of nodes and edges

OntoViz: Installation

• OntoViz uses the open source Graphviz tool from

AT&T which must be installed separately (available

for Windows and Unixes)

• the path to the Graphviz tool must be specified as an

entry in Protégé’s protege.properties file

• use Project | Configure... | Tab Widgets to activate

the OntoViz tab in a project

• see the README which is part of the distribution for

full details

OntoViz: A Simple Example

click on “C” button to create graph

OntoViz: Configurationconfiguration on a per class/instance

basisshow class

Content

showsubclasse

OntoViz: Configuration of Individual Classes and Instances

• Options for configuring individual classes and instances

• sub subclass closure• sup superclass closure• slx slot extension• isx inverse slot extension• slt slots• sle slot edges• ins instances• sys system frames

OntoViz: Configuration of Individual Slots

• Options for configuring individual classes and instances

• sub subclass closure• sup superclass closure• slx slot extension• isx inverse slot extension• slt slots• sle slot edges• ins instances• sys system frames

configuration of color(and direction) of

slot edges

OntoViz: Global Options

Protégé’s XML Tab

Importing and Exporting XML Data

A Very Short Introduction to XML

• XML is used to model (semi-)structured data:

<Customer id=“1234”> <Name> <FirstName>Bill</FirstName> <LastName>Buckram</LastName> </Name> <Cardnum>234 ...</Cardnum></Customer>

• <tag>...</tag> is called element• <tag/> is a self-closing element

(equivalent to <tag></tag>)

tag name attribute

XML Import Strategy

• tag/element names become class names, except “leaves” which become slots

• example:<Customer>

<Name>

<LastName>Buckram</LastName>

</Name>

</Customer>

Example (Import):Book Order

XML Export Strategy

• instances:• unreferenced instances become top level elements (cyclic

references are handled)• classes and slots become tag names• objects that are referenced more than

once are shared/reused with id/idref

• ontology:• as simple XML tree, RDF schema, XOL, … (future work)

Example (Export):Newspaper Instances

Example: Newspaper Ontology As XML Tree

Protégé’s RDF[S] Backend

Importing and Exporting RDF Schema Ontologies and RDF Instance Data

A Very Short Introduction to RDF

• RDF = Resource Description Framework• RDFS = RDF Schema: class and property definitions (ontology)• RDF model = directed graph = set of statements of the form

<subject, predicate, object> where subject, predicate, and objects are resources (objects can also be literals)

• Example: <http://.../Lassila, Creator, “Ora Lassila”>

• RDF in XML syntax:<rdf:RDF> <rdf:Description about="http://www.w3.org/Home/Lassila"> <s:Creator>Ora Lassila</s:Creator> </rdf:Description> </rdf:RDF>

RDF[S] Backend: Overview

• allows import and export of RDF[S] knowledge bases• can be used as an alternative to the standard text

backend• Protégé-specific extensions (allow full round trip)• plain RDF[S] also supported• full namespace and namespace abbreviation support

(included projects may have different namespaces)• uses Sergey Melnik’s rdf-api tool which is used by

most Java-based RDF applications

RDF[S] Backend: Example

• Classes and properties (RDFS file):...<rdfs:Class rdf:about="&mv;MotorVehicle">

<rdfs:subClassOf rdf:resource="&rdfs;Resource"/></rdfs:Class><rdfs:Class rdf:about="&mv;MiniVan">

<rdfs:subClassOf rdf:resource="&mv;PassengerVehicle"/><rdfs:subClassOf rdf:resource="&mv;Van"/>

</rdfs:Class>

<rdf:Property rdf:about="&mv;registeredTo” a:maxCardinality="1"><rdfs:domain rdf:resource="&mv;MotorVehicle"/><rdfs:range rdf:resource="&mv;Person"/>

</rdf:Property>...

• Instances (RDF file):

<?xml version='1.0' encoding='ISO-8859-1'?><!DOCTYPE rdf:RDF [

<!ENTITY rdf 'http://www.w3.org/1999/02/22-rdf-syntax-ns#'> <!ENTITY mv 'http://protege.stanford.edu/mv#'>

]><rdf:RDF xmlns:rdf="&rdf;”

xmlns:mv="&mv;"><mv:Truck rdf:about="&mv;test3_INSTANCE_00003">

<mv:registeredTo rdf:resource="&mv;test3_INSTANCE_00004"/></mv:Truck><mv:Person rdf:about="&mv;test3_INSTANCE_00004”

mv:name="Ora Lassila"/></rdf:RDF>

The Flora Query Tab

Querying Protégé-2000With F-Logic

Flora Query Tab

• Flora is an XSB-based F-Logic (Frame Logic)

• Protégé knowledge base is exported as F-Logic program (including axioms and queries)

• precompiled queries can now be executed in an XSB/Flora “sub-process”

• list of answers is shown in Protégé (if answers are instances)

• can also be used to model constraints (queries must/must not fail if knowledge base is consistent/inconsistent)

Flora Query Tab: Simple Example

Flora interaction

resultsrun query

Flora Query Tab: Transformation of Protégé Classes and Instances Into F-Logic

• classes:'Newspaper'::':THING'['Prototype'=>'Prototype_Newspaper'; 'Contents'=>>'Content'; 'Date'=>string; number_of_pages=>integer].

• instances:instance_00083:'Newspaper'['Contents’->>{instance_00035,instance_..., ...}; 'Prototype'->instance_00078; number_of_pages->148; 'Date'->'08/23/97'].

subclass of

instance of

values

=>, -> single valued

=>>, ->> multiple valued

Flora Query Tab: Parameters and Axioms

axiomsparameter

Protégé’s OIL Support

Modeling OIL Ontologies with Protégé-2000

Protégé’s OIL Support: Overview

• OIL = ontology inference layer

• ontologies defined via class expression inclusions and equalities

• class expressions are built with logical connectives (and, or, not)

and slot restrictions (exists, forall, cardinality restrictions)

• axioms: disjoint, disjoint cover etc.

• Protégé’s OIL support:

• Protégé’s way to define ontologies for normal cases

• metaclasses/metaslots allow complicated expressions

• special widgets for displaying OIL expressions (future version: also for editing)

• connects to FaCT description logic classifier for classification and satisfiability

checking

• generates SHIQ LaTeX output

Supported Subset of OIL

• Protégé supports the following subset of OIL:

• class definitions with subclass and slot constraints (property restrictions)

• class expressions: and, or, not, class[names], slot constraints, top, and bottom

• slot constraints: has-value, value-type, max-cardinality, min-cardinality, cardinality

• missing: concrete-type-exp, filler-exp

• slot definitions:

• subslot-of, inverse (using Protégé's inverse slot mechanism), domain, range

• properties (transitive, symmetric, functional)

• global axioms (disjoint, covered, disjoint-covered, equivalent)

• missing: instance-of, related

Protégé as OIL-Editor: Example

complex expressions (shownwith special widget):

“a herbivore eats plants andparts of plants”

class hierarchy notcompletely modeled

“giraffe isa herbivore”

“tasty-plant is not satisfable”

start classificationwith FaCT

lion and giraffeare now correctly

classified

Protégé as OIL Editor: SHIQ LaTeX Output

Protégé-2000-related Projects at DFKI(German Research Center for Artificial Intelligence)

DFKI is based in Kaiserslautern and Saarbrücken

Kaiserslautern Site

DFKI GmbHErwin-Schrödinger-StraßeD-67608 Kaiserslautern

Tel.: 0631 205 3214Fax.:0631 205 3210

email:info@dfki.uni-kl.de

Saarbrücken Site

DFKI GmbHStuhlsatzenhausweg 3D-66123 Saarbrücken

Tel.: 0681 302 5252Fax.: 0681 302 5341email: info@dfki.de

Protégé-2000-related Projects at DFKI Kaiserslautern

• FRODO

• “RDF Actions”: Protégé as ontology server

• music ontology

• KnowWork

• CLOCKWORK

• A Framework for Distributed Organizational Memories

• http://www.dfki.uni-kl.de/frodo/

• funded by bmb+f (German government)

• topics:• context support and process-knowledge evolution based on weakly

structured workflows

• scalability and cooperation between distributed OM societies

• information support by integrated formal / informal reasoning on multiple sources

• Protégé-2000 used• to model ontologies (goal: building up shared conceptualizations!)

• as knowledge base backend

• to import/export RDF[S]

FRODO: RDF Actions

• Goal: use Protégé-2000 as ontology/kb server

• communication with foreign software components (agents) via RDF messages

• RDF Actions: send actions like “create class”, “attach slot” etc. to build up kbs (future version: queries)

• Protégé-2000 was used to model most of its own API calls; actions are instances of this ontology

• RDF[S] backend used to interpret these actions

RDF Actions: System Architecture

Action Ontology (RDFS)

Protégé-2000ActionTab

Project (without GUI)

ActionMachine

Project

Protégé API

Actions/Messages (RDF)P

TCP/IP

Foreign Software Components,

Agents

RDF Actions Ontology

RDF Actions: Instances

FRODO: Music Ontology

• ongoing master’s theses

• internet portal for music

• music ontology for navigation and as background

knowledge to enhance search process

• since the ontology is expected to be quite stable, it is

exported as RDFS file and imported from the portal

software

FRODO: Music Ontology

KnowWork

• bmb+f project (German government)

• knowledge management for construction, production, and (technical) sales (area: mechanical engineering)

• Protégé used to model various ontologies:• information ontology

• classes for documents (invoice, cad drawing, ...)

• organizational ontology• company organization structure

• processes

• domain ontology (products etc.)

Protégé Modeling ofFrequency Converters in the

CLOCKWORK Project*

*Creating Learning Organisations with Contextualised Knowledge-rich WORK artefacts

DFKI: H. Boley, A. Bernardi, D. Höh, A. Mlik, S. PollmannELOTHERM: D. Stahl, R, Jürgens, A. Seitzer

ELOMAT Frequenz-Umrichter fürindustrielleElektrowärme undSonderanwendungen.

PraxisgerechtesProgramm modularerUmrichtertypen.

ELOMAT FrequencyConverters forindustrial heating andspecial applications.

Practical program of modular converter types.

Frequenz-UmrichterFrequency converters

Maintenance Report

Type Remark

Machine 222B standard

Generator C30 fusebroken

Filter

Checked fusesChanged fuse of C-Generator

Word-processor-based reports

<?xml version="1.0"?><service-instance> <rdf:RDF>. . .</rdf:RDF> <machine type="222B"> <generator type="C30" fault="fuseC"/> <filter/> </machine> <repair replace="fuseC"/></service-instance>

X M L repository

con-ver-ter

Database

AnnotatedHTMLdocumentpublishing

Formattedrelationaldata

style-sheets

Protégé-2000

FRODO agents Retrieval and inference

meta data

q u e r i e s

the-sau-rus

Ontology modeling

• For indexing free texts of ELOTHERM´s engineers reports, we build a taxonomy

• Problem: Free texts contain many synonyms (homonyms etc.) for which standard terms (disambiguated etc.) must be introduced

• Solution: Synonyms linked to taxonomy of standard terms used as an index for the reports

Free-text Taxonomy: Design

• Knowledge acquisition via Protégé

• Taxonomy consists of class hierarchy, slots, and instances

• Working on association of free-text taxonomy with machine model (partonomy plus error hierarchy)

Free-text Taxonomy: Realization

© 2001 DFKI GmbH -1- OntoViz Tab; XML Tab; RDF Backend; Flora Query Tab; OIL Support;...

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