linked-data

问题 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. 回答1: Element Set: Namespace: http://purl.org/dc/elements/1.1/ Predefined prefix: dc11 It defines 15 terms . These terms are also published as the standards ISO 15836, ANSI/NISO Z39.85, and RFC 5013. Terms: Namespace: http://purl.org/dc/terms/ Predefined prefixes: dc , dcterms It defines all terms , including the

问题 I'm running the following query at the LinkedMDB SPARQL endpoint and it works. With it, I get all the information that I need about the director of the movie with id 72, which is Titanic , so I get information about James Cameron. PREFIX mdb: <http://data.linkedmdb.org/resource/movie/> SELECT ?director?nombre_director?id_director WHERE { ?pelicula mdb:filmid ?id . ?pelicula <http://data.linkedmdb.org/resource/movie/director> ?director . ?director <http://data.linkedmdb.org/resource/movie

问题 I'm a Java developer just getting started with linked data/RDF. I can create triples, put them in a triple store, query them, etc, but it's very awkward. Most of my code is focused on the mechanics of RDF and I'd really like to work with this data in a way that's more idiomatic Java. How can I convert a POJO to/from RDF triples with Jena without hand-coding everything? I'd like something that can convert a pile of triples with a defined structure back and forth between a Java POJO and RDF.

问题 I'd like to inventory my wine collection using RDF but am not sure how to specify that wine can contain percentages of several grape varietals. Below is an attempt to do so in Turtle syntax using rdf:bag. @prefix xsd: <http://www.w3.org/2001/XMLSchema#> . @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . @prefix vin: <http://example.org/wine#> . <http://example.org/wine/id#1001> a <http://example.org/wine/ns#red> ; vin:name "Quilceda Creek CVR" ; vin:vintage "2014"^^xsd:gYear ; vin

问题 Given an RDF graph like this: :Matrix [rdfs:label] :The Matrix . :Matrix [movie:id] :23 . :Matrix [movie:actor] :Keanu Reaves . :Matrix [movie:actor] :Laurence Fishburne . :Die Hard 3 [rdfs:label] :Die Hard 3 . :Die Hard 3 [movie:id] :42 . :Die Hard 3 [movie:actor] :Bruce Willis . :Die Hard 3 [movie:actor] :Samuel L. Jackson . and a query like this: SELECT ?id ?name ?actor WHERE { ?instance movie:id ?id . ?instance rdfs:label ?name . ?instance movie:actor ?actor . } I would expect a result

问题 Slide 14 of Ontology Alignment Discovery using Linked Open Data says that there are 50,603 actors in the LinkedMDB dataset. Using the following query, I get 2500. Who is wrong here?, Is there something missing in the query? Why do the slides count such a high number? This is the SPARQL query: select(count(distinct ?actors) as ?nActors) where { ?actors a <http://data.linkedmdb.org/resource/movie/actor> . } Results 回答1: Many public endpoints impose limits on queries in order to ensure that one

问题 For @en text alone, a single item from the Wikidata dump contains multiple names: <http://www.wikidata.org/entity/Q26> <http://www.w3.org/2000/01/rdf-schema#label> "Northern Ireland"@en . <http://www.wikidata.org/entity/Q26> <http://www.w3.org/2004/02/skos/core#prefLabel> "Northern Ireland"@en . <http://www.wikidata.org/entity/Q26> <http://schema.org/name> "Northern Ireland"@en . On the Wikidata page for this article (http://www.wikidata.org/entity/Q26), which of these (if any) corresponds to

问题 Lets say there is a RDF DB of people and each of these people has many triples defining this person's friends (so many of 'person' x:hasFriend 'otherPerson' ). How can I find people who have the most similar friends? I'm a novice at SPARQL and this seems like a really complex query. Basically, the results would be a list of people starting from the ones with the most similar friends list (to the person specified in the query) and then going down the list to the people with the least similar

问题 I am trying to upload some data to Dydra from a Sesame triplestore I have on my computer. While the download from Sesame works fine, the triples get mixed up (the s-p-o relationships change as the object of one becomes object of another). Can someone please explain why this is happening and how it can be resolved? The code is below: #Querying the triplestore to retrieve all results sesameSparqlEndpoint = 'http://my.ip.ad.here:8080/openrdf-sesame/repositories/rep_name' sparql = SPARQLWrapper

问题 I am trying to write a query that will return my all CareerStation objects that are associated with Arsenal FC. Then I want to be able to get the start and end dates of these CareerStations, currently I can only get the start date. It may be that only the start date is in the DB but this doesn't make much sense to me. Also I would like to know if there is a way of formatting the date so to remove the parts that aren't the actual year. Thanks in advance for any pointers. PREFIX p: <http:/