Representing Time in RDF Part 6

I found these documents useful while researching this topic. I include them here because they could make a useful list of background reading for modelling time with RDF.

  • Refactoring BIO with Einstein Part 1: First Steps — my first post that touches on modelling of time in genealogy. At this point I was attempting to model it simply using an event model, i.e. a sequence of things that happen to people and places.
  • Refactoring BIO with Einstein Part 2: Conditions — this is the post in which I first introduced Conditions (i.e. Approach 1). The post uses almost exactly the same example as Scenario 1.
  • Refactoring Bio With Einstein Part 3: Temporal Invariants — in the third part of the series I explored those properties of a person that are timeless, or "temporally invariant".
  • Refactoring BIO with Einstein Part 4: Employment and Families — in this post I continue the theme of part 2 and demonstrate how employment periods could be described using conditions and events that mark transitions between conditions.
  • Temporal Scope for RDF Triples — in this blog post Jeni Tennison describes her attempts to model time for the London Gazette data she is working with. She describes the reified approach (Approach 3) as unacceptable because most triple stores do not deal with reified data (i.e. don't allow you to query it in its un-reified form). She describes two acceptable approaches which are N-ary relationships (Approach 4) and named graphs (Approach 2) with a preference for the latter. Some useful comments point to other examples of these approaches.
  • RDF and the Time Dimension Part 1 — in this post the author explains succinctly where the problem lies although the example used is flawed because it contains hidden context (i.e. "August is a summer month..." is not true in general and needs the context "...for those in the Northern Hemisphere", which can be modelled in RDF). The post also settles on named graphs as a solution but claims they cannot be used for continuous dimensions such as time (missing the solution of using something like OWL-Time to represent intervals and relative timings).
  • RDF and the Time Dimension Part 2 — in this follow-up post the author proposes reifying statements and adding a new predicate to relate the reified statement to the context. (A hybrid of Approach 3 and Approach 4?). A second and preferred solution using named graphs is also presented. The author also demonstrates how to obtain a snapshot of all triples that held true at a specific time under both approaches (a "snapshot").
  • OWL Time — an ontology of time concepts
  • Property Reification Vocabulary — a proposal for mapping between reified properties and classes that represent the reifications (i.e. between Approach 3 and Approach 4)
  • Temporal RDF
  • Music Ontology Events

This post is part 6 of a series about representing time in RDF. All posts in this series: part 1, part 2, part 3, part 4, part 5 and part 6

Permalink: http://blog.iandavis.com/2009/08/representing-time-in-rdf-part-6/


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