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Questions tagged [ontology]

Ontology is a formal representation of knowledge as a set of concepts within a domain, and the relationships between those concepts. Those concepts and relationships create graph-structures and can be described by the lattice theory or other mathematical models.

The ontology describes a domain of knowledge by concepts. All the relationships among concepts are represented in the ontology like concepts too. In general, we talk about the Cartesian multiplication of sets where our concepts can be like objects and subjects. As result, we can represent knowledge on the ontology by 5 level of definitions, namely: abstract, semantic, structural, conceptual and data levels.

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What is the difference between RDF and OWL?

I am trying to grasp the concept of Semantic Web. I am finding it hard to understand what exactly is the difference between RDF and OWL. Is OWL an extension of RDF or these two are totally different technologies?
user32262
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Are there any tools to visualize a RDF graph? (please include a screenshot)

I'm looking for a tool that will render a RDF graph in a reasonably useful graphic format. The primary purpose of the graphic format being inclusion into a PowerPoint slide or printing on a large plotter for management review. I am currently using…
Eric Schoonover
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What is the difference between GraphQL and SPARQL?

I'm doing a lot of research right now on Semantic Web and complex data models that represent relationships between individuals and organizations. I knew a little semantic ontologies although I never understood what it was used if not make graphs. I…
Erwan Pesle
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What is the difference between DatatypeProperty, ObjectProperty, & FunctionalProperty, and when should I use them?

When writing an ontology, there are several very commonly used types, including: DatatypeProperty ObjectProperty FunctionalProperty InverseFunctionalProperty The first three kinda look like they'd be used in a particular set of ways, but I find my…
Kristian
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What is an Ontology (Database?)?

I was just reading this article and it mentions that some organization had an Ontology as(?) their database(?) layer, and that the decision to do this was bad. Problem is I hadn't heard about this before, so I can't understand why it's bad. So I…
Robert Gould
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Ontology vs vocabulary

I have recently started working with semantic web and linked data technologies, I have been always confused about one thing though. What is the difference between an Ontology and a vocabulary? Which is preferable?
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The best tool for visualizing ontologies?

I am looking to visualize ontologies for understanding and making others understand. I would prefer to have top-down hierarchy of classes. I have used OntoGraph which comes with Protégé, but I am not happy with the figure :(. I have also used…
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Semantic Search in Python for hobbies + latest news

I want to implement a python based semantic search over a set of keywords (mainly hobbies, latest news, etc which people might be interested to talk about). I want to know if there exist an ontology database(s) for the same and open source search…
w2lame
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Where can I find a good collection of public domain owl ontologies for various domains?

I am building an ontology-processing tool and need lots of examples of various owl ontologies, as people are building and using them in the real world. I'm not talking about foundational ontologies such as Cyc, I'm talking about smaller,…
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can we use owl:SameAs between two predicates?

What is the difference between using and Here NS is some namespace.
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How get DBpedia data in a specific language?

i tried this request http://lookup.dbpedia.org/api/search.asmx/KeywordSearch?QueryClass=film&QueryString=transformers&MaxHits=1 but if i want to retrieve info in italian language? it there another service (similar this) that can?
Leonardo
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What is the difference between dublin core terms and dublin core elements vocabularies

There's 2 Dublin Core vocabularies DC terms and DC elements. They define almost the same classes and properties. So what is the key differences between them, and when to use each one.
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What is the difference between an Information Model and an Ontology?

What is the difference between an Information Model and an Ontology? They look the same to me. Thanks!
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Geographical ontologies ready to use?

I'm looking for an ontology containing geographical knowledge. In particular I'd like to have these types of information: political states / regions / cities / city areas geographical regions (e.g. continents, name of mountains, lakes, etc) For…
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How to query Classes with Object Property in Sparql

Does any one know how to query Classes with Object Property in Sparql? Assume we have an OWL file which contains follows Human ----(hasPizza)---> Pizzas Human and Pizzas are classes (or concepts). In SPARQL, this query returns nothing: select ?x ?y…
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