semantic-web

问题 I have defined an ontology with the following classes, properties, and individuals with object property assertions: Class: Employee > Individuals: { EmployeeA } Class: Skill > Individuals: { Skill1, Skill2, Skill3 } Class: Job > Individuals: { DBA } hasSkill > Domain (Employee) and Range (Skill) isAskillBy > Domain (Skill) and Range (Employee) <inverse of hasSkill> requireSkill > Domain (Job) and Range (Skill) isAskillrequiredBy > Domain (Skill) and Range (Job) <inverse of requireSkill>

问题 I would like to know if SPARQL, by default, adopts the open world assumption or if this depends on the triple stores that execute the SPARQL queries. And what are the implications of this assumption in queries. Best regards. 回答1: Well.... I wonder whether this is really a good question for this site. I think not, but I'm gonna throw a few cents into the bucket anyway. To start with -- does it matter whether SPARQL "adopts" (and what does that mean, to you?) OWA, and, if so, why? Then, to

问题 I have deployed Sesame 2.8.6 server and workbench on Wildfly-8.2.0.Final. I created a new In Memory repository like this: I clicked "Create" and the repository was created: If I restart Wildfly-8.2.0.Final the repository that I created disappears. It doesn't persist. Am I missing something? I also tried versions 2.8.5 and 2.8.4 and it was the same result: the repository did not persist. When I tried version 2.8.3 of sesame the repository persisted. Logs from [ADUNA_DATA]/OpenRDF Sesame/logs

问题 I am studying Semantic web while trying to create a simple single page application (SPA). The SPA should be able to display various rdf data (and also allow the user to create new ontologies in a user friendly way). I have full controll of the format of the ontologies (meaning I can state if they are represented as RDF/XML, ntripples, turtle etc. and also I can decide, if I want to use ontologies to describe how the data should be displayed). From what I read in the Fresnel Manual I think

问题 I am trying to extract the hierarchy of Wikipedia category or Yago classification for DBpedia resources using the SPARQL endpoint. For instance, I would like to find out all the possible categories and classes in hierarchical form of entity, say, http://dbpedia.org/resource/Nokia, like Thing → Organization → Company → … → Nokia. 回答1: A simple SPARQL select can retrieve the information that you're interested in, though it won't be arranged hierarchically. You're interested in getting all the

问题 I'm trying to define class of intervals. Each interval object may have (optionally) at most two boundary points. One of them - lower boundary, and another - upper boundary. How can I restrict my class of intervals, so that lower and upper individual boundary points must be different (if provided)? 回答1: You can declare that the hasLowerBound and hasUpperBound properties are disjoint. This means that an individual with values for both cannot have the same value for both. Here's an example. I've

问题 I am new to Freebase and I have been trying to find relationships between 2 nodes without success. For example, I want to find if there is link between Lewis Hamilton(/en/lewis_hamilton) and Formula One(/en/formula_one), which there is in real life, but I can't seem to find it. I have tried the following MQL codes, alternating IDs as well : 1) [{ "type" : "/type/link", "source" : { "id" : "/en/lewis_hamilton" }, "master_property" : null, "target" : { "id" : "/en/formula_one" }, "target_value"

问题 This question is related to this question: Uniform way to add multiple descriptive properties in Schema.org Recently I found this code on HTML5 & Schema.org - Structured Microdata for SEO, along with the statement that the Schema.org WPHeader type is a WebPageElement that can include markup from CreativeWork as well as Thing : <header role="banner" itemscope itemtype="http://schema.org/WPHeader"> <meta itemprop="name" content="A name"> <meta itemprop="description" content="A description text"

问题 I am trying to run this query on http://dbpedia.org/sparql but I get an error that my query is too expensive. When I run the query trough http://dbpedia.org/snorql/ I get: The estimated execution time 25012730 (sec) exceeds the limit of 1500 (sec) ... When running the query through my python script using SPARQLWrapper I simply get an HTTP 500. I figure I need to do something to optimize my SPARQL query. I need the data for iterating over educational institutions and importing it in to a local

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 5 months ago . I need to import dbpedia into neo4j. I download the dbpedia from here: http://wiki.dbpedia.org/Downloads37 Any idea? 回答1: I am currently doing the same thing. I found that the biggest problem for this is the indexing so the best solution is to write a java program that extracts