Knowledge Content Objects: a grounded ontology for content management over the semantic web Aldo...

Knowledge Content Objects: a grounded ontology for content management over the semantic web

Aldo Gangemi

Laboratory for Applied Ontology

Istitute of Cognitive Sciences and Technology

CNR, Rome

[email protected]

Laboratorio di Ontologia Applicata, CNR-ISTC, Roma/Trento

Ontology application: the state of play

| Ontologies used for any purpose, from domain to task to application (service) modelling

| Ontology building easier when limited to small communities for small tasks in simple applications, and as a controlled terminology (cf. FOAF)

| Real world applications are more difficult: medium to large organizations and communities, complex tasks (otherwise why bothering?), not only controlled terminologies, distributed and networked communities, need to manage inconsistency, conflicts, evolution, provenance, severe integration problems

| Ontologies for humanities pose specific problems, due to typical problem solving (or problem dropping) procedures --- interpretation being a major challenge

| Just like in human cognition, we need patterns emerging out of complexity


Related projects

| DOLCE and its extensions: http://dolce.semanticweb.org| Reusable reference ontologies, in various logical languages| CIDOC2DOLCE: alignment and extension of CIDOC, ask me

| OntoWordNet: http://www.w3.org/2001/sw/BestPractices/WNET| Migration of WordNet to formal ontology

| Metokis: http://metokis.salzburgresearch.at| 6th FP project, just finished, see this presentation

| W3C Semantic Web Best Practices and Deployment Working Group: http://www.w3.org/2001/sw/BestPractices/

| CODePs: see my ISWC2005 paper: Ontology Design Patterns for Semantic Web Content, web page with a repository asap

| NeOn: http://www.neon-project.org| 6th FP IP project: networked, collaborative ontologies, starts in March


How Metokis fits in the OE state of play

| Application and content modelling are getting closer| Ontology patterns used in conceptual modelling| Case tools used in ontology engineering| KOS being reengineered or at least ported to semantic models

| Abstraction step: going “outside the computational box”| Social tasks and knowledge: support for knowledge collectives| Computational tasks should become a(n executable) part of a social

process of knowledge elicitation, negotiation, and sharing

| Metokis ontologies are an attempt to fill the modelling gap between social and computational tasks and knowledge

| Plan Ontology| IO and KCO Ontology| Ontology Design Patterns| Everything based on the DOLCE foundational layer


Modelli di progettazione ontologica

| Design pattern:, esempi di risoluzione di problemi generati da analisi dei requisiti

| In architettura (Alexander): modelli di progettazione da “buoni esempi”| Nel software engineering (Gamma et al.): componenti software

sperimentati| In ingegneria ontologia?

| Content Ontology Design Pattern: modelli concettuali, esempi di risoluzione di problemi generati da analisi dei requisiti

| CODeP logici: soluzioni a partire da vincoli logici| CODeP concettuali: frammenti di ontologie, ricchi di relazioni e

costruitii per soddisfare le necessità degli esperti/utenti di un dominio


Modularità: Stratificazione dei moduli

Domain ontology

{Sculpture,Restoration, Mythical being, Caryatid, Doric order, Armilla, Fresco, …}

Core ontology (specific domain-independent)

{Work of art, Painting technique, Author, Artistic period, Plastic art, Interpretation, …}

Foundational ontology (domain-independent)

{Object, Process, Part, Time, Location, Representation, Plan, …}

Inherits from

Inherits from


Criteri di costruzione: Sfingi


Quante (e quali) sfingi?

monument

plays_role

stoney objectto be restored

plays_role

instance-of

Greek mythical creature

instance-of statue

subclass-of

refers_torepresents

Englishexpressed_according_to

class

individual

word

Aegyptian mythical creature

instance-of

“sphinx”

The Sphinx

sphinx

Sphinx

sphinx

Sphinx

sphinx

metaphoricalblending

symbolic figure

instance-of

pharaoh

metaphoricalblending

*refers_to

* in naïve iconography

“Oedipus and the Sphinx”

represented_by

lexicalizeslexicalizes

lexicalizeslexicalizes

lexicalizes

lexicalizes

interpersonal role

instance-of


Quali modelli di progettazione ho usato?

| Classe Individuo, istanza_di(individuo, classe)| Parola Entità, lessicalizza(parola, entità)| Oggetto informativo Individuo, rappresenta(oggetto informativo, individuo)| Oggetto informativo Concettualizzazione, esprime(Oggetto informativo,

concettualizzazione)| Oggetto Ruolo, gioca(oggetto, ruolo)| Individuo@spazio1 Individuo@spazio2,

fusione_metaforica(individuo@spazio1, individuo@spazio2)

| !!! Informalmente parlando … in realtà rappresentati in linguaggi logici computabili (KIF, OWL(DL), CL, etc.)


Cosa ci faccio?

Ex: query su dati semistrutturati (ex. documenti in un Semantic Web)

«tell me what works of art from ancient Egypt are related to European works of art that also involve Greek mythology in a same cultural unit»

(retrieve (?x1 ?x2) (exists (?y ?z ?k) (and (creation_3 ?x1) (creation_3 ?x2) (non-physical-object ?y) (or (and (represents ?x1 ?y) (origin ?y Classical_Greece)) (exists ?w (and (non-physical-object ?w) (represents ?x1 ?w) (refers-to ?w ?y) (origin ?w Classical_Greece)))) (or (and (represents ?x2 ?y) (origin ?y Classical_Greece)) (exists ?w1 (and (non-physical-object ?w1) (represents ?x2 ?w1) (refers-to ?w1 ?y) (origin ?w1 Classical_Greece)))) (origin ?x1 EGYPTIAN_EMPIRE$EGYPT) (origin ?x2 EUROPE))))


Altri modelli

| Oggetto informativo Oggetto fisico, realizzato_da(oggetto informativo, oggetto fisico)

| Oggetto informativo Dati concreti, codificato_da(oggetto informativo, dati concreti)

| Oggetto fisico Dati concreti, digitalizzato_da(oggetto fisico, dati concreti)

| Regolamento situazione, soddisfatto_da(regolamento, situazione)| sse: tutti o alcuni dei ruoli, compiti, parametri, etc. definiti nel

regolamento hanno una corrispondenza nella situazione


Altri enigmi per le ontologie relative ai beni culturali

| Artefatti object-oriented e process-oriented, ex. scultura vs. musica

| Periodi artistici: intervalli di tempo, eventi, o descrizioni di stili?

| Autenticità: valutazione basata su criteri locali

| Interpretazione: | entità rappresentate vs. figure simboliche, allusioni, rimandi

“intertestuali”| significato implicito ed esplicito, della critica e del pubblico

| Metaphorical blending


Riutilizzare l’esistente!

| “Magazzini” culturali| Reingegnerizzazione di legacy design patterns| Tassonomie e campioni materiali| …

| Elicitazione dei modelli di razionalità degli esperti e degli utenti reali


The basic DDPO Design Pattern


Information objects: a foundation for content description and KCO[a semiotic ontology design pattern]


Formally …

• Class(DnS:information-object complete • intersectionOf(• DOLCE:social-object • restriction(DnS:about allValuesFrom(DOLCE:particular)) • restriction(DnS:realized-by someValuesFrom(DOLCE:information-

realization))• restriction(DnS:interpreted-by allValuesFrom(Actions:agent))• restriction(DnS:expresses allValuesFrom(DnS:description))• restriction(DnS:ordered-by someValuesFrom(DnS:information-encoding-

system))))

| The definition says that information objects (IO):| are ordered by some information encoding system| are realized by some particular (an “information realization”)| can express a description [and, if that description is satisfied by a situation,]| can be about that situation, or some entity in its setting| can be interpreted by agents that internally represent the description expressed by IOs


IO pattern for Dante’s Comedy


Content objects

| “Content” is ambiguous. WordNet (v2.0):| Depicted object| Sum of what is perceived, discovered, or learned| What a communication that is about something is about| Everything that is included in a collection

| In KCO ontology, COs realize information objects| MP3 file, eBook, JPEG image, QT movie, etc.| Either digital (computational objects) or analog (non-digital)

| Therefore, COs are information realizations


Semantic facets of (paid) content objects

| Content descriptions: provides the propositional content that is announced by a digital content on an abstract level.

| Community descriptions: information about the organisational structure (roles, rights and obligations) by which a content product can be used and information that influences trust such as certificates and brand name information.

| Business descriptions: describes the business and legal requirements during information and negotiation phases. After a purchase, contracts will be enforced according to mutually agreed rights and obligations.

| Presentation descriptions: describes the presentation modes to which the information of a content product can be adapted to by rendering and other application-specific means.

| Trust and Security descriptions: content must be associated with some measure of trust for the end user, and for the content provider, there must be some security features which guarantee that the content will not be illegally copied or otherwise misappropriated.


Aligning Knowledge Content Objects with a Foundational Ontology

| Are physical data structures (realize a frame - a data structure - for content objects), hence they are information realizations

| Generic KCO: realizes a maximally generic frame (a -unique- ontological schema)

| Domain-anchored KCO: specializes a generic KCO by realizing an ontological schema about the community and business elements. Furthermore, it commits its instances to a domain specific ontology which can be as broad as desired

| KCO Prototype (Master Copy): instantiates a domain-anchored KCO (by filling at least some of the schema slots) and contains, at a certain point in time, a particular digital content including all semantic annotations required by the corresponding domain-anchored KCO

| KCO Instance (Copy) : it also instantiates a domain-anchored KCO, but is treated as a “copy” of a prototypical KCO, e.g. generated when a user is granted access to a content object. Depending on the contract, this copy can change over time, through alterations made by the owner. For example, somebody may buy a MIDI backing track for a pop song, in order to modify it, e.g. by adding her own voice to it, or changing some parts

A kind of information object in DOLCE!

A kind of information object in DOLCE!


KCO (master or copy layer) formalization

• Class(KCO:KCO complete• KCO:physical-data-structure• restriction(DnS:realizes someValuesFrom(intersectionOf(• KCO:data-structure • restriction(KCO:instantiates someValuesFrom(intersectionOf(• KCO:data-structure • restriction(DnS:realized-by someValuesFrom(KCO:domain-KCO))))))))• restriction(KCO:realizes-frame-for someValuesFrom(KCO:content-object))• restriction(KCO:content someValuesFrom(DOLCE:particular)) • restriction(KCO:time-based-rendition someValuesFrom(KCO:script))• restriction(KCO:interaction-based-rendition someValuesFrom(KCO:script))• restriction(KCO:usage-context someValuesFrom(DnS:plan))• restriction(KCO:user-task someValuesFrom(DnS:task))• restriction(KCO:content-user someValuesFrom(unionOf(• DnS:organization Collectives:collective DnS:role)))• restriction(KCO:contract-semantics• someValuesFrom(CommonSenseMapping:contract))• restriction(KCO:negotiation-semantics someValuesFrom(KCO:negotiation-protocol))• restriction(KCO:pricing-semantics someValuesFrom(KCO:pricing-scheme))• restriction(KCO:trust-value someValuesFrom(KCO:trust-region))• restriction(KCO:mappable-to allValuesFrom(KCO:ForeignClass)))


Complementary axioms for KCO facets (examples)

• SubClassOf(• restriction(KCO:realizes-frame-for someValuesFrom(• restriction(DnS:realizes someValuesFrom(• restriction(DnS:about someValuesFrom(DOLCE:particular)))))• restriction(KCO:content someValuesFrom(DOLCE:particular)))

• SubClassOf(• restriction(KCO:realizes-frame-for someValuesFrom(• restriction(DnS:realizes someValuesFrom(• restriction(DnS:expresses someValuesFrom(DOLCE:particular)))))• restriction(KCO:content someValuesFrom(DOLCE:particular)))

• EquivalentClasses(• restriction(KCO:user-task someValuesFrom(DnS:task))• restriction(KCO:usage-context someValuesFrom(intersectionOf(• DnS:Plan• restriction(DnS:defines someValuesFrom(DnS:task)))))


CD: Content DescriptionCO: Community SemanticsBS: Business SemanticsPR: Presentation SemanticsSD: KCO Self-DescriptionAC: Access Semantics

BS

CD

CO

PR

AC

SD

KCO Structure

real

ises

information object

Foundational

Ontologyis-defined-in



BS

CD

CO

PR

AC

SD

KCO Structure

real

ises

information object

Foundational


Domain-Model

DomainOntology



BS

CD

CO

PR

AC

SD

KCO Structure

real

ises

information object

Foundational


Domain-Model

DomainOntology



BS

CDCO

PRAC

SD

KCO Structure

real

ises

information object

Foundational


Domain-Model

DomainOntology


Resource Integration S.

KCTP Services

Task Services

Reasoning Services

V V

C C

W

Ser DSer

Send Rec

TaskExecution

Env.

ReasoningEngine

KCCARegistry

KCCAManager

Domain-specific Services

Applic-spec.Services

KCO Operations

Propositional content

...

KCO API API extensions Env. API

Applications / Interaction layer

GUI

KCCA

Network

Business semantics

Community description

Presentation description

KCCA Services

KCCA architecture


Metokis service taxonomy


APPLICATION LAYER

Local System Registry

HTTP Message

HTTP Message

HTTP Sender/Receiver Servlet

HTTP Sender/Receiver

KCTP Router

De-SerializerSerializer

HTTP MessageKCTP Message RDF

Model

KCTP Message RDF Model

Check/ Get / Register KCCA Service

KCCA Service

COMMUNICATING WITH OTHER KCCA NODESResponse KCTP Message

Request KCTP Message

PRESENTATION LAYER

|_S1_| |_S2_| |_S3_|…………………...|_SN_|

SERVICES CONTAINERRepository ServicesKCO ServicesRegistry Services

METOKIS REPOSITORY API

WRAPPER

DATABASE DATABASE

METOKIS WORLD

HTTP Message

KCTP Message

KCTP Message KCTP Message

Components in KCCA/KCTP. KCTP Handler consists of KCTP Router, HTTP Sender Receiver, HTTP Sender

Receiver Servlet, De-Serializer and Serializer.


KCO in the real World

| Three layers| Content

| The actual content of the KCO| Human readable (e.g. contract.pdf, salzburg.jpg)| Machine readable (e.g. config.xml, rss_newsfeed.xml, ...)| Analog content (e.g. A book located at urn:room3:shelf2:loc43)

| Content Description Layer| Access, format and encoding information (MM-Facet)| Provides a referable placeholder to any content or content segment

| Semantic Layer| The actual knowledge of the KCO



| This layering holds for all facets| ! That means that each facet may include content, e.g.:

| The contract facet may include the human readable contract.pdf as content in addition to the semantic statements in the semantic layer of the facet

| The propositional content facet provides a semantic description of the domain, but the current and approved XML-Document can still be used

| Even the MM-Metadata facet may include a MPEG7 or Dublin Core File in addition to the semantic statements part of this facet



| Advantages of this approach| KCOs do not break existing Applications

| Content of the KCO provides compatibility to existing components (Even tasks provided by humans)

| Newly developed XML-Standards can be used in combination with KCOs

| Seamless migration to Semantic Web Technologies| It’s not necessary to provide a “complete” ontological description of

the problem domain| Concentration on some key requirements is possible| Steadily improvement of the semantic description based on

feedback and future requirements

Date post:	20-Dec-2015
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Knowledge Content Objects: a grounded ontology for content management over the semantic web Aldo...

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