- From: Dave Caroline <dave.thearchivist@gmail.com>
- Date: Mon, 2 Mar 2015 07:48:12 +0000
- To: Simon.Cox@csiro.au
- Cc: Richard.Wallis@oclc.org, public-vocabs@w3c.org
The mixing of fuzzy and textual and numeric dates makes me think of a similar problem in sorting text which is solved by collation(sorting rule) in a database. http://stackoverflow.com/questions/341273/what-does-character-set-and-collation-mean-exactly I think dates classified this way would become easy to search, sort and intermingle expressions of dates Dave Caroline On 01/03/2015, Simon.Cox@csiro.au <Simon.Cox@csiro.au> wrote: > Also note that as soon as you get into 'named' time periods, then you have > to tangle with non-Gregorian calendars. > ISO 8601 only deals with Gregorian dates. XML Schema (and, transitively, > OWL-Time) inherit this limitation. > > This doesn't work for many situations, not only geologic time and > pre-historic time, but also non-Gregorian calendars used currently in some > communities (Hebrew, Arabic, Baha'i calendars). > > And then there are coordinate systems, like Unix time and Loran-C, which > express time with a number on a line with a direction and origin. > > See > http://semantic-web-journal.net/content/time-ontology-extended-non-gregorian-calendar-applications-0 > for a longer discussion, along with proposed solutions for OWL applications. > > > > -----Original Message----- > From: Dave Caroline [mailto:dave.thearchivist@gmail.com] > Sent: Sunday, 1 March 2015 5:23 AM > To: Wallis,Richard > Cc: public-vocabs@w3c.org > Subject: Re: Circa. dates > > It gets worse, dates have bugged me for a long time a few examples one sees > circa 300BC Jurassic period Caroline period > http://en.wikipedia.org/wiki/Caroline_era > 16th century > > Database designers seem to have dodged the issue > > Dave Caroline (name not related to the period I think) > > > On 28/02/2015, Wallis,Richard <Richard.Wallis@oclc.org> wrote: >> Hi all, >> >> With colleagues I have been looking at how we might handle historical >> approximate dates in Schema.org<http://Schema.org>. The initial >> requirement being to be able to describe an old book or manuscript >> published say in approximately 1765. A common need in the >> bibliographic world, with the normal string based solution being >> "circa. 1765", or "c. 1765" - Wikipedia providing some >> examples<http://en.wikipedia.org/wiki/Circa>. >> >> The knee-jerk reaction was to suggest some sort of >> approximateDateCreated property for CreativeWork which would not only >> help us bibliographic folks but also those in museums and galleries >> with similar date approximation needs. >> >> Broadening the analysis it became clear that this need could be >> applicable in most any case where you would expect a >> Date<http://schema.org/Date> in the range of a property. birthDate, >> deathDate, dateCreated, datePublished, foundingDate, all being all >> potential candidates for Circa style dates. >> Rolling things into the future you could imagine other examples such >> as wanting to describe the last serviced date of a vehicle being circa >> 2013. >> >> So how to solve this in a simple, yet generic, way? >> >> We could take advantage of the default "if you haven't got a specified >> type for a property, a Text is acceptable" pattern in Schema, and just >> put in a text string with a defined format: "c.1765". >> >> Perhaps a more appropriate solution would be to define a new data >> type, to be added to the range of suitable properties. >> >> My pragmatic (KISS and don't break stuff) view of this leads me to >> suggest a new data type named 'circaData', or maybe 'approximateDate' >> as a subType of Date. With descriptive information in the Type >> definition explaining why/how you would use it in the use cases I describe >> above. >> >> This approach would add this important functionality, for those >> describing old stuff, without the need for major upheaval across the >> vocabulary, and would at least default to a date for those that do not >> care or look for such approximation aspect of dates. >> >> ~Richard >> >> > >
Received on Monday, 2 March 2015 07:48:40 UTC