Machine Tags allow users to describe custom properties and relate online resources using a syntax based on subject-predicate-object triples, enabling uses like geotagging photos, field-based search, and linking to semantic web data. However, Machine Tags have limitations in expressing complex object values and semantic relationships. The document discusses how the software gnizr implements Machine Tag support by detecting tags, looking up locations in an external database, and notifying listeners to process and store the tag information.
6. What else can you say about ¡°photo-1293¡±? Resources Relates to a YouTube video (link?) John Smith is in this picture (homepage?) Taken on 2007/12/03 @ 10:00PM Johnny is the photographer (homepage?) Relates to a family trip (trip¡¯s homepage?) Location Piccadilly Square (latitude/longitude?)
7. Describing and relating resources The amount of user-generated content is growing on the Web (flickr, youtube, last.fm, upcoming, etc.). New problem How to describe ¡°ad-hoc¡± properties about the resources that we have created How to relate multiple resources that we have created across multiple Web sites What¡¯s an ¡°ad-hoc¡± property?
8. Machine Tags Tags with a special syntax that allow users to describe ¡°ad-hoc¡± properties and relate distinctive resources across multiple Web sites. + = http://www.flickr.com/groups/api/discuss/72157594497877875/
9. Triple Model Machine Tag syntax is based on the Triple model, similar to which of the RDF language. Subject Predicate (Property) Object (Value) Johnny Photo-1923 takenBy
10. Machine Tag Syntax There is no one standard syntax. Different systems may have variations of the original syntax proposed by Flickr. [namespace] : [predicate] = [object] Subject Predicate (Property) Object (Value) Where is the ¡°Subject¡± in the syntax?
11. Machine Tag example Resource Predicate Object Johnny Smith Photo-1923 foo:takenBy [namespace] : [predicate] = [object] foo : takenBy = ¡°Johnny Smith¡±
13. Relating resources What if I want to say ¡°photo-1923¡± relates to ¡°event-1393¡± on upcoming.yahoo.com¡ Subject Predicate Object Photo-1923 upcoming:event http://upcoming.yahoo.com/event/1393 upcoming:event=1393
14. I machine-tagged, but what use? Machine Tags can be used for Geotagging: putting your photos on a map Field-based search: search with prefix URL shortcuts: include image and video in your blogs without much HTML editing Semantic Web experiments: describe properties that link to RDF or OWL documents ¡ What¡¯s your experience with Machine Tags?
15. Interesting use of Machine Tags What camera did u use? About the airplane
16. Machine Tags for selling books http://adactio.com/journal/1274/ amazon:asin=1234567890 book:isbn=1234567890 http://learningtheworld.eu/2007/amazon-machine-tags/
17. Relating Flickr photos with a blog post http://adactio.com/journal/1274/ Collective intelligence?
18. Machine Tag for field-based search There are overlaps between the Machine Tag syntax and field-based search. Benefit : learn one syntax and use it in two different ways
19. Machine Tag for building taxonomy? Google Code allows administrator to define ¡°Issue Labels¡±.
20. Relating resources to RDF/OWL Geonames.ORG http://sws.geonames.org/5352844/about.rdf geonames:feature=5352844 http://www.geospatialsemanticweb.com/2007/03/28/geonames-machine-tags
21. Shortcomings of the Machine Tags Lack of control vocabulary Who says you should or should not use what tags? Do you use ¡°geonames:feature¡± or ¡°gn:f=¡± Difficult to express ¡°object¡± of a complex value geo:lat/lng=23.00,39.23 (ugly, parser is need) geo:lat=23.00, geo:lng=39.23 (okay) What if I want to express multiple coordinates: geo:lat=23,00, geo:lng=39.23, geo:lat=33.00, geo:lng=-30.00, ... (How do I interpret the key/value pairs?) Difficult to describe certain semantic information we will see an example.
22. Where is your kid? Tagged: - person=john person=mary person=david landmark=power_station Who is John? Power Station?
23. Machine Tags in Gnizr How ¡°tags¡± are stored What does gnizr do when a ¡°machine tag¡± is detected How to add new implementation to process new types of ¡°machine tag¡±
26. GeonamesTagListener.java Find all ¡°machine tags¡± of ? gn:geonames=[location] Get the latitude and longitude pair for [location] from Geonames.org. Add POINT(lng,lat) about a bookmark to the DB.
27. Listen for new Machine Tags Extend from BookmarkListener Add new listeners to the BookmarkManager
28. Summary Machine Tags are tags with a special syntax that allow users to describe ¡°ad-hoc¡± properties and relate distinctive resources across multiple Web sites. Use in geotagging, field-based search, foring URL shortcuts and experimenting with Semantic Web technology Machine Tags have certain shortcomings in expressing rich semantic information.