博文
- 语义网的历史
- Web本来就应该是语义网的，可是最初却只能是语法网。这个是Web发明人的观点：Tim Berners-Lee “... a goal of the Web was that, if the interaction between person and hypertext could be so intuitive that the machine-readable information space gave an accurate representation of the state of people's thoughts, interactions, and work patterns, then machine analysis could become a very powerful management tool, seeing patterns in our work and facilitating our working together through the typical problems which beset the management of large organizations.”
现在我们从未Web增加一些sementic annotation来入手. - Web Ontology Language Requirements:
- Extends existing web standards - such as XML, RDF, RDFS
- Easy to understand and use - should be based on familiar KR idioms
- Formally specified
- Of "adequate" expressive power
- Possible to provide automated reasoning support
-
- OWL and RDF are much of the same thing, but OWL is a stronger language with greater machine interpretability than RDF.
- OWL comes with a larger vocabulary and stronger syntax than RDF.
-
-
- A taxonomy is a collection of controlled vocabulary terms organized into a hierarchical structure.
- A controlled vocabulary is a list of terms that have been enumerated explicitly.
- A thesaurus is a networked collection of controlled vocabulary terms.
- People use the word ontology to mean different things, e.g. glossaries & data dictionaries, thesauri & taxonomies, schemas & data models, and formal ontologies & inference. A formal ontology is a controlled vocabulary expressed in an ontology representation language. This language has a grammar for using vocabulary terms to express something meaningful within a specified domain of interest. The grammar contains formal constraints (e.g., specifies what it means to be a well-formed statement, assertion, query, etc.) on how terms in the ontology’s controlled vocabulary can be used together.
-
- as a set of building blocks and rules used to build models
- as a model of a domain of interest, and
- as an instance of another model.
A meta-model is an explicit model of the constructs and rules needed to build specific models within a domain of interest. A valid meta-model is an ontology, but not all ontologies are modeled explicitly as meta-models. A meta-model can be viewed from three different perspectives:
-
Bottom line: Taxonomies and Thesauri may relate terms in a controlled vocabulary via parent-child and associative relationships, but do not contain explicit grammar rules to constrain how to use controlled vocabulary terms to express (model) something meaningful within a domain of interest. A meta-model is an ontology used by modelers. People make commitments to use a specific controlled vocabulary or ontology for a domain of interest.
-
-
Cyc - Wikipedia, the free encyclopedia
- Cyc is an artificial intelligence project that attempts to assemble a comprehensive ontology and knowledge base of everyday common sense knowledge, with the goal of enabling AI applications to perform human-like reasoning.
-
-
WordNet - Wikipedia, the free encyclopedia
- WordNet is a semantic lexicon for the English language. It groups English words into sets of synonyms called synsets, provides short, general definitions, and records the various semantic relations between these synonym sets. The purpose is twofold: to produce a combination of dictionary and thesaurus that is more intuitively usable, and to support automatic text analysis and artificial intelligence applications
- Cognitive Science Laboratory of Princeton University
-
没有评论:
发表评论