An introduction to the Semantic Web for Museums

1. An introduction to the Semantic Web for Museums Presented at Museums and the Web 2006, Albuquerque Dr Mike Lowndes, Interactive Media Manager, Natural History Museum, London mikel@nhm.ac.uk

2. The semantic web: Contents • Web futures: context • What is it? • Web problems: Digital objects and other issues • Building blocks • Steps along the way • Current applications • Other advances – Web2.0 • Activity in the cultural sector • Is it actually going to happen? • Conclusions for Museums

3. Web Futures We can be assured that • Whatever we propose today, the future will be different. • Technology progresses and conceptual thought keeps playing catch-up. New ideas supplant old. • The future ‘web’ will be as messy and tricky to predict as the past. So… • For Museum web users, we should strive toward a greater signal to noise ratio.

4. Web futures: Other Developments • Web 2.0: web as application platform • Convergence • The web becomes more TV-like, but remains interactive and always available. • More layers of information on more channels. • It will become optionally immersive: degrees of immersion depending on how you interact with it. • Internet 2www.Internet2.org • Infrastructure, for massive bandwidth. • Grid computingwww.gridcomputing.com • Shared processing: increasing available power when connected. • Computing power becoming a utility like electricity. • Towards instant processing of everyday tasks (in the human timeframe).

5. Web Futures: Internet Ubiquity. • All technological devices connected. • The intelligent fridge, RFID, mobiles with GSM, GPRS, G3. • Future mobile device: operate your bank account, hifi and front door lock, turn the car heater on before you get to it – these things are not that far away. • The ‘web’ is already old-school. • We don’t yet have a simple word for the continuum between digital radio, TV, the web, mobile internet, sms and multimedia kiosk interactions, though internet technology underpins it all. • We can no longer limit our thinking to the needs of the desktop browser-based ‘web’.

6. Problems with the current Web

7. Problems: A Digital Object • Digital object. • Named Anomalocaris. • Did that help? • If we need help to make sense of many digital objects, Google needs even more. • So: A digital object should include or connect to the supporting data that allows both humans and machines to understand it. • Answer: The semantic web: • Provides a framework, standards and tools for attaching, extending, making available and understanding the ‘meaning’ of digital objects. • Makes the digital medium self-explaining.

8. Problems: the worst things about today’s web? • Its ‘manual’. • Google is currently the most popular way to begin exploring a topic. • It relies on humans to link sensibly to interesting and relevant content. This only works when a LOT of humans are making the links. • Hyperlinks. They are dumb. • They do not explain themselves. • Can you trust them? • When you create them, you need to keep validating them. • Searching for new links to make requires a search engine. • Metadata can improve this, but metadata is poorly used. • Answer: The semantic web

9. Problems: how many logins do you have? Bank1 Bank2 Sharedealing Work VPN Basecamp Amazon eBay eBuyer Picstop Flickr Email 1 Email 2 Etc………………. • What about an infrastructure that allows you to ‘log on’ to the internet just once? • Answer: The semantic web.

10. Some Web Issues For Museums • People trust online museum’s content and their links more than others, perhaps. • But our knowledge and collections are not easily available for the public, as a single ‘collection’ relevant to their needs. • This requires breaking down the digital walls between institutions: digital access, interoperability, flexible context. • Interoperability is a difficult thing. • Our metadata is easy to publish, but nothing ‘out there’ uses it to improve searching. • Attempts are being made (e.g. OAI-PMH) • GBIF • Other portals • Answer: The semantic web.

11. Definitions and goals.

12. The Semantic Web • Tim Berners-Lee – Web Visionary and head of W3C. • Formally set off in 1998: Goal is the solution to information overload and the personalisation of the web. • ‘Adding logic to the web’ • If you’re 38 and some available content is aimed at six year-olds, then its not appropriate to prioritise display (unless you’re searching for your kids). This kind of logic is built into the semantic web. • ‘Turning the web into a global database’ • Semantic web software should be able to find, sort, classify, interpret, and present relevant content in context. • Achieved via global use of metadata leading to vastly improved ‘browsing’, and agents which may seem intelligent because they can process a web that describes itself.

13. W3C Definition • Tim Berners-Lee: • ‘The Semantic Web is an extension of the current Web in which information is given well-defined meaning, better enabling computers and people to work in cooperation.’ • For the Web to become a truly machine-readable resource, the information it contains must be structured in a logical, comprehensible and transparent fashion. • This is the primary work required to ‘enable’ the semantic web.

14. The Building Blocks How do we get there?

15. What the Semantic Web Will Require • Adoption of metadata standards. • Usable tools for automatic and semiautomatic multilingual knowledge mark-up. • Modelling relationships. E.g between types of metadata. • Construction of ontologies (and mappings between them). • Stay awake! • Plus, intelligent agents to ‘mine’ the above for a particular person’s needs. • Defining a particular person requires a user profile.

16. Boxes And Arrows – No Clouds! Context A digital object User profile Other ontologies Maps to User query, or query generated by user behaviour Semantic Web Agent Maps to and is constrained by Identified ontologies • Accurate, • meaningful • Answers • Actions • Views of information Associated metadata

17. W3C: Current Semantic Web Work (2006) • A roadmap. Two ‘formal’ XML technologies are now part of the first generation semantic web: • RDF for holding and communicating the metadata. • OWL for describing relationships and inferring meaning.

18. W3C: Semantic Web RoadMap

19. 1. XML • XML underpins the next step. • It can describe the 'data' on the web by wrapping that data in tags that explain it. • E.g.<product><fruit>orange</fruit><price>20</price><currency>gbp</currency></product> • XML is a framework. • Ad-hoc files can be created in it for specific uses, using any tags you like. • There is no need to formally describe them unless you want them to be understood outside your particular use.

20. XML Languages for Describing Content • You can formalise a tag set written in XML by creating a ‘config file’ for it, known as a Document Type Definition, or more recently, a Schema. • e.g. • Summary Metadata: Dublin Core and its derivatives. • Data Markup: Encoded Archival Description, RSS. • XML can also format and transform itself with XML ‘stylesheets’: XSL/XSLt. • Formal XML ‘languages’ underpin the semantic web. • XML over the internet: enables machine-to–machine communication.

21. 2. RDF: Resource Description Framework • W3C supports the development of the “Resource Description Framework ”. • RDF is the ‘official’ current encoding format for semantic web data. • Can contain data, metadata and relationships. • E.g. Dublin Core, RSS. • Make web resources self-describing. • RDF-S (a more recent development) • ‘Schema’ provides some ontology support to RDF. • E.g. Simple DC file

22. 3. Ontologies - OWL • W3C supports the development of the Web Ontology Language,usually abbreviated as OWL. • What is an ‘ontology’? • A dictionary defines the meaning of words. • A taxonomy or classification system describes hierarchical relationships between things but not usually other kinds of relationships. • A thesaurus deals with wider relationships between words but meaning by inference only. • Ontologies join taxonomies and thesauri together and can derive logic and inference – relationships of meaning. • OWL is the latest iteration of this idea as applied to the web. • It is a ‘vocabulary extension’ of RDF – not something ‘different’.

23. Brainbreak - FenFire Ouch, my brain hurts.

24. Definitions and Properties of an Ontology • James Hendler: • “a set of knowledge terms, including the vocabulary, the interconnections in meaning, and some simple rules of inference and logic for some particular topic.” • ‘DigiCULT: • “The most typical kind of ontology for the Web has a taxonomy and a set of ‘inference rules’.” • What does it do? Describes relationships between data. • TBL: • An ontology may express the rule "If a city code is associated with a state code, and an address uses that city code, then that address has the associated state code.” = the functionality of a database (query) and a thesaurus (meaning by context).

25. How Will Ontologies Be Used In The Semantic Web? • Ontologies can be domain-oriented, task-oriented, application-oriented or general purpose. Also called ‘class taxonomies’. • ‘Upper Ontologies’ are more general and can tie more specific ones together by ‘mapping’ them. • e.g. How can we make a machine understand that ‘watercolours’ are linked to ‘jewellery’ semantically? • Concept of ‘watercolour’ links to a definition URI (url). • Local ontology: ‘watercolour is a type of painting.’ • Local ontology: ‘necklace is a type of jewellery’. • Upper ontology: ‘painting’ and ‘jewellery’ are both types of ‘art’. • Someone needs to build these mappings. • Now, do it all again in multiple languages…

26. A lot of talk… • Foundational ontologies - shared understanding, providing intended meaning of a vocabulary. • Completeness, precision and overlap between ontologies agreement on all are needed for 'establishing consensus'. • Gets philosophical very quickly: • is a hole different from the region of space it occupies? I.e. Are there holes, or only holed objects? • Is a statue different from the stuff it is constituted by? I.e. Are there statues or only statue-shaped stuffs? • Is a person different from their body? Ontologies - There will be a lot of them…

27. W3C: Semantic Web RoadMap

28. Higher layers of the Roadmap • Rules layer - early stage work • Initial proposals to provide standardised languages for the querying of RDF: SPARQL - Joseki query engine. • Experiments with rule languages: RuleML • Proof • Authority, encryption • Trust • (PICS) • Profiles • FOAF – friend of a friend. EARL

29. Long Term: Agents • DigiCULT: • Agents are the final ‘product’ of the semantic web – automatic, even artificially intelligent software that does all your searching for you (the process of narrowing down) and much more. However, this is a very long term goal and there are many steps on the way, each of which can help. • Examples: • The agent attached to your diary automatically organises travel etc, and can change your travel tickets when you alter your diary. • The agent attached to your house automatically organises food purchasing, bill payment, lighting, heating, alarms etc.

30. Visual navigation of ontology (Sculpteur) • Visualising RDF metadata: An aid for Museum professionals, not the public. • Addis, M., et al., New Ways to Search, Navigate and Use Multimedia Museum Collections over the Web, Figure 3, in J. Trant and D. Bearman (eds.). Museums and the Web 2005: Proceedings, [CD-ROM: ISBN 1-885626-31-2] Toronto: Archives & Museum Informatics, March 31, 2005 (right click/click-hold (Mac) for notes)

31. Boxes, arrows – and Acronyms Context A digital object OWL User profile FOAF/ EARL Other ontologies Maps to User query, or query generated by user behaviour RDF-S/ OWL (CIDOC-CRM, SKOS) SPARQLRuleML Semantic Web Agent Maps to and is constrained by Identified ontology • Accurate, • meaningful • Answers • Actions • Views of information RDF (DC, RSS) Associated metadata

32. Q. Why isn’t the semantic web here? • A. Its hard to do.

33. Steps along the way

34. Short Term: some current applications Making digital resources self-describing… • RSS – in RDF • Was ‘rich site summary’, now ‘really simple syndication’ - making simple summary information self-describing. • Mobile devices: CC/PP. • called Composite Capability/Preference Profile (CC/PP). • will let cell phones and other non- standard Web clients describe their characteristics to other software and agents. • Business: XBRL. • describes/classifies content of financial statements. • makes report generation easier. • FOAF • Friend of a Friend. • Describes people and their interests, plus network of peers. • www.foaf-project.org/ • Topic Maps. • A framework forcreating and browsing relationships. • Works within and between between systems and disciplines. • Works with RDF. • Human friendly; relatively easy to grasp how it works -browsers are in development.

35. Haystack (MIT) an ‘RDF-PIM’

36. Medium Term: e.g. 'smart links' As ‘semantic’ content appears browsers can be modified to use it. On mouseover…. • Metadata of target. • [More information on evolution]. • Multiple targets. • [More information on evolution]. • These do not even need to be defined as ‘links’ – simply highlighting words could initiate the ‘semantic web browser’. • Its ‘automatic for the people’. • As well as ‘smart links’ more and more ‘local domains’ of knowledge will be related by their linking ontologies. More semantic portals will appear. Author: the Natural History Museum, London. Date published: July 2005. Description: A website exploring evolution by natural selection. Audience: 12 years plus. Language: English (international). Link: definition of evolution. Link: evolution at the Natural History Museum. Link: evolution at the American Museum of Natural History. Link: Evolution on god.com. Link: evolution at New Scientist magazine. Definition: Evolution: part of natural history. Browse evolution.

37. Magpie IE plugin (Open University)

38. So nothing practical even yet? (Semagix – can you afford it?) Semantic web portals?

39. An aside? The Web 2.0 tag cloud or ‘folksonomy’

40. Web 2.0: the Web as Application platform - first uses: social networking, content authoring and sharing, real-time GIS, feedback • Flickr • Google Maps / Earth • Del.icio.us (bookmarking) • Technorati (blog-tracking) • Wikipedia • Basecamp, ACEproject • Blogger • Open source frameworks (e.g. Drupal) • Amazon, Yahoo

41. AJAX • Advanced javascript to send / receive content and update parts of pages, using XML over the web • can use other messaging formats as well – thus getting around another ‘issue’ with the web from the start; pages being static. • ‘Real-time’ response to user input i.e. approaching true desktop applications on the web. Beyond the original Berners-Lee vision? Examples: • Google Maps (map data) • Basecamp (saving changes/state without reloading pages) • Writely (word processor for online collaboration) • Shell Wildlife Photographer of the Year

42. Social Tagging (folksonomies) • The old Yahoo / Google (DMOZ) directories method of classifying sites is hardly used as a search aid • also ungainly, complex and impossible to maintain • 'tagging' is communities of web users freely keywording their content • These sites then use popularity and associations of keywords to infer relevance/closeness of meaning • http://www.flickr.com/photos/tags/family/clusters/ • provides a simple way to group content • What about specialist knowledge? • Specialist knowledge = fewer people = worse tagging? • Go visit the steve project

43. RSS • Newsfeed reading via Really Simple Syndication is now huge • a simple but structured way to syndicate information or ‘broadcast’ change • A subscription model: people get the information they want delivered to them as it is generated • Gets around an original web turnoff – having to revisit favourite sites regularly. • Content from many sources can be aggregated into themed ‘feeds’ • Use of truly semantic ideas is at an early stage, • RDF is extensible • will improve as the sheer number of newsfeeds requires new layers of interpretation. • Will be embedded in next generation operating systems e.g. 24 Hour Museum

44. Web2.0 and the Semantic Web • Joshua Allen, 2001 (Making a Semantic Web): Until anyone can create metadata about any page and share it with everyone there will not be a semantic web • Web 2.0?! • Web 2.0 is NOT a new infrastructure for the web. It won’t do the job of providing the ‘global database’. It does take steps in the right direction.

45. What has the cultural sector done? Done? – this is mostly ‘old’ stuff.

46. We Have ARole. • Were are the holders of knowledge and authority, and can help to define the semantic web. • Thesauri owned and created by Museums could become ontologies and act as part of the backbone. • Museums are behind and will remain behind as other areas see competitive advantage: business, commerce and research. • DigiCULT Thematic issue 3, 2003 – museums need to take a lead. We need to do a big project together; Standardise thesauri, develop ontologies.

47. Infrastructure : The CIDOC Conceptual Reference Model • A common language and extensible semantic framework to which any cultural heritage information can be mapped. The ‘interoperability glue’. • Provides the ‘words’ and ‘relationships’ we can use to map our stuff together. • I.e. an agreed framework for our ontologies • An international standard. • Exposed in RDF already – RDF-S/OWL to follow? • http://cidoc.ics.forth.gr/ • For an introduction, download: http://www.rlg.org/en/downloads/2002metadata/gill/gill.PPT

48. Portal example: Sculpteur • Several collections brought together into one place, one meta – database or portal. • Content from the V&A among others. • Visual display of relationships. • A published ontology in RDF. • Concept-based searching based on a semantic network. • Content-based searching of images and 3d models. • http://www.sculpteurweb.org/ (Browser needs downloading)

49. Richard Light Museum thesauriin Topic Maps • Ontology framework written to thesaurus standards. • Museum thesauri turned into ontologies in Topic Map format. • Topic Map browser (Omnigator) a visual environment. • Aims to provide ‘meaning’ – an authoritative reference that software can use when searching the web. • Could become part of the future semantic web ‘backbone’. • Topic Map / RDF interoperability now a focus at W3C Museums Computer Group Newsletter, April 2004.

50. VICODI – ‘Visual Contextualization of Digital Content’ • ‘semi-automatic creation of contextual semantic metadata for digital historical resources, by users’. • ‘Visualisation of richly structured, contextualised content’. • Interface uses historical maps and colour-coded links. • Felt to be not generally usable in hindsight by the developers, but still in some development. • http://www.vicodi.org/