rdf

问题 I wanted to model partner relationship like the following, which I expressed in the format of labeled property graph. I wanted to use RDF language to express the above graph, particularly I wanted to understand if I can express the label of the "loves" edge (which is an URI to an article/letter). I am new to RDF, and I know the RDF can easily express the node properties in the LPG, but is it possible to conveniently express the edge properties? A bit more context of this question: the reason

问题 How can I use the SWI-Prolog Semantic Web Library to make a query into the OWL/RDF file and extract some information? The OWL/RDF file is having information about all the Debian packages so I need to make the query in order to find package dependencies. For Example: The OWL file is structured as follows: package: A Depends: package: B pacakge: C How can I load a OWL/RDF file into a Prolog script and what is the syntax to make a query within the Prolog script such that I put A as a parameter

问题 could you please explain me the difference between rdfs:domain and rdfs:range with an example? and when should i use domain and when range? i have read h w3c rdf primer but i did not understand the difference 回答1: From a simplistic point of view, the domain and range properties are there to give you insight into the way that the property links a subject to an object. In the case of the domain property , when you link a subject to an object using a property with this associated attribute, then

问题 It is a follow up question to : How to list and count the different types of node and edge entities in the graph data using SPARQL query? So assuming I have the different node entities and edge entities of a given graph, how do I go about listing all triples, given a node-edge-node pattern? And how do I generate ALL node-edge-node patterns given the node and edge entities? Example: If there is a network consisting of papers(nodes), authors(nodes), conferences(nodes), iswrittenby(edge),

问题 I have an Ontology where users can use one of five predicates to express how much they like an item. The Ontology contains specific predicates that have a property called hasSimilarityValue. I am trying to do the following: Having a user let's say rs:ania Extract all the items that this user has rated before. (this is easy because the Ontology already contains triple from the user to the items) Extract similary items to the items that have been extracted in step 2 and calculate their

问题 I am executing the SPARQL query below with Jena, where uriNode is a String representing a URI , but this query doesn't give me any results. I've already checked the database and this URI does exist there. What's the problem? String queryString2 = "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> " + "PREFIX dc: <http://purl.org/dc/elements/1.1/> SELECT ?author WHERE { " + "?document dc:creator ?author." + "FILTER (?document = \"" + uriNode + "\" ). }"; 回答1: AndyS's answer is right,

问题 I'm using Jena and Sparql to query the ontology file. I have class Tag with two subclasses : C++ and Java. class Subject with several subclasses, which stand for particular University subjects: "C++ programming","System programming", "Java programming" etc. ObjectProperty "hasTags" domain:Subject range:Tag. Each class subject has some tag like "Java", "C++" When executing query SELECT ?subject WHERE { ?subject owl:equivalentClass ?restriction . ?restriction owl:onProperty ont:hasTags .

问题 If I have classes ABC and CDE defined as intersections of classes A,B,C,D,E as follows: <Class rdf:about="&blah;ABC"> <equivalentClass> <Class> <intersectionOf rdf:parseType="Collection"> <Restriction> <onProperty rdf:resource="&blah;hasMarker"/> <someValuesFrom rdf:resource="&blah;A"/> </Restriction> <Restriction> <onProperty rdf:resource="&blah;hasMarker"/> <someValuesFrom rdf:resource="&blah;B"/> </Restriction> <Restriction> <onProperty rdf:resource="&blah;hasMarker"/> <someValuesFrom rdf

问题 I tried searching over the internet but could not find the right tool for the purpose,so if anyone could provide me a link to the tool which could parse and display a graph for RDF and OWL ontologies 回答1: SemWebGraphicalNotation — W3C-maintained list of graphical notations and software applications (outdated); RDF Visualization at Ontotext Research Space; VOWL: Visual Notation for OWL Ontologies — almost standard graphical notation for OWL visualization, the page contains links to

问题 I am struggling to load most of the Drug Ontology OWL files and most of the ChEBI OWL files into GraphDB free v8.3 repository with Optimized OWL Horst reasoning on. is this possible? Should I do something other than "be patient?" Details: I'm using the loadrdf offline bulk loader to populate an AWS r4.16xlarge instance with 488.0 GiB and 64 vCPUs Over the weekend, I played around with different pool buffer sizes and found that most of these files individually load fastest with a pool buffer