Blogs and the Semantic Web

Slide 1: John Breslin Blogs and the Semantic Web john.breslin@deri.org DERI Reading Group www.johnbreslin.com 19th April 2005 1 © Copyright 2005 Digital Enterprise Research www.deri.org Institute. All rights reserved.

Slide 2: Overview • Blogs • Syndication • RSS / Atom • Semantic Blogging 2

Slide 3: Blogs: A Phenomenon for a New Generation? • Cincinnati Enquirer, October 2004 3

Slide 4: Blogs: Introduction • Weblog, web log or simply a blog • A web application which contains periodic time-stamped posts on a common (usually open-access) webpage • Individual diaries -> arms of political campaigns, media programs and corporations (e.g. the Google Blog) • Posts are often shown in reverse chronological order • Comments can be made by the public on some blogs • Latest headlines, with hyperlinks and summaries, are syndicated using RSS or Atom formats (e.g. for reading favourite blogs with a feed reader) 4

Slide 5: Blogs: Screenshot 5

Slide 6: Blogs: The Irish Connection • April has seen an explosion in awareness of Irish blogs • “The Big Bite”, RTÉ1, 5th April, David McWilliams talked to some prominent Irish “bloggers” • Irish “blogosphere” (boggersphere!) size is in the hundreds, see: – http://blog.whoisireland.com/index.php?p=43 • Aggregations of Irish blog content: – http://www.irishblogs.ie/ – http://www.planetoftheblogs.com/ 6

Slide 7: Blogs: The Irish Connection (2) • Irish blogs meetup in Dublin’s IFC (16th April) • Mix of techies and journalists • Issues discussed: – Blogger self-protection – Raising the profile of Irish blogs – Classifying blogs • Irish bloggers’ resources: – groups.yahoo.com/group/irishblogs – del.icio.us/tag/irishblogs – flickr.com/photos/tags/irishblogs 7

Slide 8: Syndication: Introduction • Content is provided from many websites in a common format that can be used by other sites in a “syndication” process • For example, content from RTÉ and Ireland.com is syndicated so that headlines can be integrated by other people into their own websites • Syndication format is usually RSS • Some sites use a different syndication format (e.g. Blogger.com uses “Atom”) 8

Slide 9: Syndication: Aggregators and Readers • Check feeds on a regular basis: – Previously, semi-regular visits to bookmarked sites resulted in a lack of accuracy in monitoring information – Now, intelligent pushing of feeds (e.g. with “pingback”) can be facilitated using integrated newsreader solutions (Outlook, Mozilla, etc.) • Display only new or updated posts • Pull info from multiple sites and puts it on your desktop • Allow you to quickly scan for relevant content 9

Slide 10: Syndication: Aggregators and Readers (2) • http://en.wikipedia.org/wiki/News_aggregator – http://en.wikipedia.org/wiki/Mozilla_Thunderbird (Desktop) – http://www.feedreader.com/ (Desktop) – http://www.newsgator.com/ (Desktop) – http://www.2rss.com/news (Web) – http://www.newsisfree.com/ (Web) – http://www.syndic8.com/ (Web) – http://www.planetplanet.org/ (Server) – htp://lilina.sourceforge.net/ (Server) – http://minutillo.com/steve/feedonfeeds/ (Server) 10

Slide 11: Syndication: Planet Of The Blogs • POTB, an Irish blogs server-based aggregator • Started 1st April; in press (Sunday Tribune) on 17th April! • ~300 “Irish” blogs at present, open inclusion policy 11

Slide 12: Syndication: Planet DERI 12

Slide 13: RSS: Introduction • The most common syndication format(s) • Acronyms: – “Really Simple Syndication” – “Rich Site Summary” – “RDF Site Summary • Eight “flavours” (not including Atom!) • More than just blog headline syndication, since RSS can be used for libraries, recipes, shared calendars (RSSCalendar.com) and newspaper articles (one of the original usages) 13

Slide 14: RSS: Explosion of Feeds • http://www.syndic8.com/stats.php?section=overview 14

Slide 15: RSS: Technologies • RDF: – RSS 0.90, 1.0, 1.1 – RSS 1.0 is the preferred Semantic Web vocabulary for blog syndication; use XSLT to transform RSS 0.9x/2.0 to RSS 1.0 – Using RDF allows the inclusion of other vocabularies to supplement the terms in the RSS 1.0 vocabulary, e.g. dc:author (Dublin Core), foaf:homepage (Friend of a Friend) • XML: Extensible: RDF – RSS 0.91, 0.92, 0.93, 0.94, 2.0 1.0 0.9 0.91 0.92 2.0 Atom Simple: Plain XML 15

Slide 16: RSS: Development Timeline • Also, RSS 1.1 released in 2005 16

Slide 17: RSS: Comparison Table Version Owner Pros Status Recommendation 0.9 Netscape Obsoleted by 1.0 Don't use Use for basic syndication. Officially obsoleted by 2.0, Easy migration path to 2.0 if 0.91 UserLand Drop dead simple but still quite popular you need more flexibility 0.92, 0.93, Allows richer metadata than 0.94 UserLand 0.91 Obsoleted by 2.0 Use 2.0 instead Use for RDF-based RSS-DEV RDF-based, extensibility via applications or if you need Working modules, not controlled by a Stable core, active module advanced RDF-specific 1 Group single vendor development modules Extensibility via modules, easy migration path from Stable core, active module Use for general-purpose, 2 UserLand 0.9x branch development metadata-rich syndication • http://www.xml.com/pub/a/2002/12/18/dive-into-xml.html 17

Slide 18: RSS: 1.0 Terms • Class “channel”: – Property “title” – Property “link” – Property “description” – Property “items” (rdf:Seq) – … • Class “item”: – Property “title” – Property “link” – Property “description” – … 18

Slide 19: RSS: 1.0 Example <?xml version="1.0"?> <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns="http://purl.org/rss/1.0/" > <channel rdf:about="http://sw.deri.ie/~jbreslin/ttdig/ttdig_tourist.rss"> <title>TTDIG Tourist</title> <link>http://sw.deri.ie:2020/~jbreslin/ttdig/index.php?jcategory=tourist</l ink> <description>Things to Do in Galway, Tourist</description> <items> <rdf:Seq> <rdf:li resource="#1" /> <rdf:li resource="#2" /> … </rdf:Seq> </items> </channel> … 19

Slide 20: RSS: 1.0 Example (2) <item rdf:about="#1"> <title>Galway: St. Nicholas' Cathedral</title> <description>Located on Market Street, Galway. St. Nicholas' Collegiate Church dates from the 12th century. Christopher Columbus visited this church in 1477, fifteen years before he set out for the New World. Sometimes hosts concerts, a nice venue where Lambchop and gospel singers alike have played.</description> </item> <item rdf:about="#2"> <title>Galway: Lorna McMahon's Gardens</title> <description>Located in Bushy Park, Galway. Only allows visitors once a year! Magnificent gardens which surround Lorna Mc Mahon's home and were created by her single handed. For 25 years, she has carved out a delightful and in places magical garden from hazel wood, rough scrub, rocks and bog. The garden extends over 4 acres, and is subdivided into 12 gardens each with its own specialty. The garden is a personal project and several sections are called after friends and relatives. There is a Japanese garden with a large brooding 'snow viewing' lantern and by way of contrast there is a herbal garden laid out in Elizabethan style containing all the herbs mentioned in the Bible or in Shakespearean plays.</description> </item> … </rdf:RDF> 20

Slide 21: RSS: For Libraries • Useful for both librarians and members of libraries since libraries publish lot of announcements, e.g. general notices, activity bulletins, online resources, and TOCs for journals • NUI Galway’s library uses RSS 1.0 to publish lists of their new books and resources: – http://www.nuigalway.ie/web/add-ons/rss_reader.html • “Uthink” is a project of the University of Minnesota that allows students and personnel of the University to have their own blogs: – http://blog.lib.umn.edu/ 21

Slide 22: Atom: Overview • Another syndication system • Based on XML (not RDF) • Emphasis has shifted from the format to the API • Specification: – Constructs: content, people, dates and links – Elements: feeds, with entries – http://www.atomenabled.org/developers/syndication/atom- format-spec.php 22

Slide 23: Semantic Blogging: Introduction • Packages of structured data are becoming post components • The virtue of blogs has been their simplicity • Each post only needs one field for content, and maybe a title and URL • Not everyone is served well by this lowest common denominator 23

Slide 24: Semantic Blogging: Structure-Enhanced Blog Item • Sometimes you have a burning need for more structure, at least some of the time • When you know a subject deeply, and your observations or analysis recur, you may be best served by filling in a form • The form will have its own metadata and its own data model • Uses: – People get to express themselves, and – Blogs start to interoperate with enterprise applications 24

Slide 25: Semantic Blogging: Soccer School Coach Example • An after-game report typically includes: – which teams played – where and when – officials, and – a list of game events: • who scored (and when and how) • who received penalties (when and for what), etc. • Wouldn't it be handy for the coach’s blogging tool to understand this structure, present an editing form, render the form in HTML to their blog, and render the post (including the form) to their RSS feed? 25

Slide 26: Semantic Blogging: Aggregators and Readers • News aggregators and news readers should be able to: – Auto-discover an unknown structure – Notify the user that a new structure is available – Learn the structure, including entry forms, pick list sources, rendering guidance, and default style sheet – Make it available when the blogger is ready to write 26

Slide 27: Semantic Blogging: Some Real World Examples • Qlogger: http://www.qlogger.com/ – Sub-schemas describe activities (golfing, commuting) and reviews (movies, marijuana) – This creates more comparable data (e.g., show me all the movie reviews by the “warbloggers” group rated 4 out of 5 stars) – Trend charts so a person can see if their golf game is getting better or worse, or if their commute times are better on some days • Lafayette Project: http://www.megnut.com/weblogs/002594.asp – A person can review a book on their blog or post a review on Amazon, but it would be better if they could just tell Amazon about the review on their own site (more distributed) – It would be useful to link recipes (and their reviews) to Epicurious and collaboratively filter that info (people who cooked this also cooked this) – A person can get to own their content but also can connect with others, retain copyright and still participate in useful discussions • JemBlog: http://ideagraph.net/jemblog/ 27

Slide 28: Semantic Blogging: Linking Posts by Topic • Posts are often categorised (e.g., “Galway”, "Movies”) • Those on similar topics can be grouped together, using: • Technorati tags: – Tags are category names, for people to categorise blog posts, photos, links, etc. – Technorati.com wants to build a “tagged” web • SKOS categories: – http://www.wasab.dk/morten/blog/archives/2004/09/01/skos- output-from-wordpress – http://www.w3.org/2004/02/skos/ 28

Slide 29: Semantic Blogging: Haystack 29

Slide 30: Semantic Blogging: Haystack (2) 30

Slide 31: Semantic Blogging: Haystack (3) 31

Slide 32: Semantic Blogging: SIOC • Current Interlinks: 32

Slide 33: Semantic Blogging: SIOC (2) • Future Interlinks 33

Slide 34: Semantic Blogging: Knud’s semiBlog • Another aspect of semantic blogging is annotating posts and associated multimedia in blog posts with RDF metadata (by drag-and-drop apps), for example: • A blog post (with an attached photo) says “This is a picture of Mary Smith on St. Patrick’s Day in Galway” and has an associated topic category of “Irish Culture” • Can annotate the text “Mary Smith” by linking to her homepage and her FOAF profile if they exist, and annotate St. Patrick’s Day, Galway and the topic “Irish Culture” with some rdfs:seeAlso links or descriptions • Can also add some annotation to the photo, such as what it depicts, when it was taken, file location, etc. 34

Slide 35: Semantic Blogging: Knud’s semiBlog (2) 35

Slide 36: References – http://feedvalidator.org/ – http://purl.org/rss/1.0/ – http://inamidst.com/rss1.1/ – http://dannyayers.com/2003/08/rss.htm – http://www.intertwingly.net/wiki/pie/Motivation – http://www.intertwingly.net/wiki/pie/NoToRdf – http://www.atomenabled.org/ – http://www.technorati.com/ – http://dijest.com/aka/2003/08/23.html#a2584 – http://www.w3.org/2001/sw/Europe/events/foaf- galway/papers/pp/semblog_personal_publishing_platform/ – http://urfistinfo.blogs.com/urfist_info/files/distribrss.ppt – http://theory.csail.mit.edu/~dquan/iswc2004-blog.pdf 36