Mike Lowndes,

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A Beginners Guide to the Semantic Web
UKMW 2005 The future of the Digital Object

• Mike Lowndes,
• Interactive Media Manager,
• Natural History Museum, London

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Contents

• Web futures.
• Digital objects.
• The semantic web Definitions, goals and
  components.
• Steps along the way, short, medium and long term.
• Examples from Museums.
• Is it actually going to happen?
• Conclusions for Museums and a call to action.

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Web Futures

• The future web is an unknown country. Whatever we
  propose today, the reality will very likely be
  different.
• Technology progresses and conceptual thought
  keeps playing catch-up with it. New ideas
  supplant old.
• The future web will be as messy as the past.
• So
• For Museum purposes, we should strive toward a
  greater signal to noise ratio.

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Web futures Other Developments

• Convergence
• The web becomes TV-like, but remains interactive
  and always available.
• More and deeper layers of information.
• It will become optionally immersive degrees of
  immersion depending on how you interact with it.
• Internet 2 www.Internet2.org
• Infrastructure, for massive bandwidth.
• Grid computing www.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).

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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 dont 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.

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Back to the Digital Object

• Digital object.

• Named Anomalocaris.
• Did that help?
• If we need help to make sense of many digital
  objects, Google etc need even more.
• A digital object should include or connect to the
  supporting data that allows both humans and
  machines to understand it.
• The semantic web will
• Provide standards and tools for attaching,
  extending and making available the meaning of
  digital objects.
• Make the digital medium self-explaining.

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What are the worst things about todays web?

• Its manual a pull technology.
• Google is currently the most popular way to begin
  exploring a topic.
• It relies on humans to link sensibly to
  interesting and relevant content.
• Hyperlinks. They are mostly 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

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Web Issues For Museums

• People trust museums and their links more than
  others, perhaps.
• But our knowledge and collections are not
  available easily for the public, as a single
  collection relevant to their needs.
• We all see this interoperability as a difficult
  thing. It is.
• Our metadata is easy to publish, but nothing out
  there uses it to improve searching.
• Attempts are being made (e.g. OAI-PMH- see notes)
• Answer The semantic web.

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The Semantic Web

• Tim Berners-Lee Visionary.
• Leading W3C, hes ahead of the game.
• Goal is the solution to information overload.
• 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.
• Adding logic to the web
• If youre 38 and some available content is aimed
  at six year-olds, then its not appropriate to
  prioritise display (unless youre 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.

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W3C Definition

• TBL
• 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.

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What the Semantic Web Will Require

• DigiCULT (Themed issue 3, 2003)
• Adoption of metadata standards.
• The development of 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!

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Boxes and arrows no clouds!
Context
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

• A digital object

Associated metadata
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The Building Blocks

• How do we get to the semantic web?

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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.ltproductgtltfruitgtorangelt/fruitgtltpricegt20lt/price
  gtlt/productgt
• 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.

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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.
• Rich Metadata Encoded Archival Description.
• XML can also format and transform itself with XML
  stylesheets XSL/XLSt.
• Formal XML languages for structuring,
  communicating and understanding data will
  underpin the semantic web.
• Web Services will enable machine-tomachine
  communications using these XML languages.

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Current Semantic Web Work of W3C (2005)

• A roadmap.
• Two formal technologies now part of the first
  generation semantic web
• RDF for holding the information.
• OWL for describing relationships and inferring
  meaning.
• There is a lot more in development
• E.g. FOAF friend of a friend.

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1. W3C Semantic Web RoadMap
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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.
• Makes web resources self-describing.
• RDF-S (a more recent development)
• Schema provides some ontology support to RDF.

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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.
• In a faceted taxonomy things exist on more than
  one branch of the hierarchical tree.
• E.g Nature contains Life (biology etc) and
  Earth (geology etc) Dinosaurs Life gt Reptiles gt
  Dinosaurs, or Earth gt Fossils gt Dinosaurs
• A thesaurus deals with wider relationships
  between words but meaning by inference only.
• Ontologies join these together and can derive
  logic and inference.
• OWL is the latest iteration of this idea.
• (partly based on yet another DAMLOIL)
• It is a vocabulary extension of RDF not
  something different.

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FenFire

• Ouch, my brain hurts.

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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.
• Standards for describing and showing
  relationships between data.
• DigiCULT
• The most typical kind of ontology for the Web
  has a taxonomy and a set of inference rules.
• 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).

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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.
• watercolour links to a definition URL.
• watercolour is a type of painting.
• a necklace is a type of jewellery.
• painting and jewellery are both types of
  art.
• Someone needs to build these relationships.
• They will be built in RDF/OWL (at least, for
  now).
• Now, do it all again in multiple languages.

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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

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Boxes, arrows and Acronyms
Context
User profile
OWL
FOAF
Other ontologies
Maps to
User query, or query generated by user behaviour
RDF-S/ OWL (CIDOC-CRM)
Semantic Web Agent
Maps to and is constrained by
Identified ontology

• Accurate,
• meaningful
• Answers
• Actions
• Views of information

RDF

• A digital object

Associated metadata
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Building blocks 2

• Steps on the way to the
• semantic web

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Short Term some current applications

• Making digital resources self-describing
• RSS
• rich site summary, 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 for creating and browsing
  relationships.
• Works within and between between systems and
  disciplines.
• Works with RDF.
• Human friendly relatively easy to grasp how it
  works -browsers in development. (Omnigator)

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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.
• Author the natural history museum.
• Date published May 2005.
• Description A website exploring evolution by
  natural selection.
• Audience 12 years plus.
• Language English (international).
• Multiple targets.
• More information on evolution.
• Link definition of evolution.
• Link evolution at the Natural History Museum.
• Link evolution at the American Museum of Natural
  History.
• Link evolution at New Scientist magazine.
• Definition Evolution part of natural history.

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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.

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• What is the cultural sector doing?

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We Have A Role.

• 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 currently behind and will remain
  behind as other areas see competitive advantage
  business, commerce, even research.
• DigiCULT Thematic issue 3, 2003 museums need
  to take a lead. We need to do a big project
  together Standardise thesauri, develop
  ontologies.

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Examples 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.
• Proposed as 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

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Example Sculpteur

• Several collections brought together into one
  place, one meta database or portal.
• Content from the VA 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)

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Richard Light Museum thesauri in Topic Maps

• Ontology framework written to thesaurus
  standards.
• Museum thesauri turned into ontologies in Topic
  Map format.
• Topic Map browser provides a visual environment
  (Omnigator) for checking.
• Aims to provide meaning an authoritative
  reference that software can use when searching
  the web for Museum objects.
• Can become part of the future semantic web
  backbone.
• MCG Newsletter, April 2004.

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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 development.
• http//www.vicodi.org/
• http//www.eurohistory.net/Index.do

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VICODI - powered
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Finnish Museums on the Semantic Web

• The most ambitious and realised attempt.
• Uses RDF encoded Dublin Core metadata.
• Brings 15 Museum collections together.
• Appears as a basic, text based search and browse
  interface a bit like an automated Yahoo
  directory.
• Difficult to assess as it is in Finnish, but has
  good critical reports from users.
• A semantic web HTML generator is in development.
• http//museosuomi.cs.helsinki.fi/

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Finnish Museums on the Semantic Web
All the right buzzwords in all the right places.
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Finnish Museums on the Semantic Web
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Finnish Museums on the Semantic Web
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Coda Reality Check

• Is the semantic web the right approach to
  information overload?

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Problems with structuring knowledge

• All knowledge codified? The web will always be
  chaotic.
• Its hard to do, not easy like the current web.
• Initially it will be used by the formal web.
• commerce
• academia
• b2b
• education
• institutions
• The informal web (most blogs/wikis, personal
  pages, link sets etc) will benefit from the work,
  and will get tools eventually.
• Consider the speed of technological advance
• by the time we get close to it, something better
  will come along.

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Nay-sayers?

• DigiCULT Janneke Van Kersen, Dutch Digital
  Heritage Association.
• I do not believe in developing a fundamental
  ontology to give meaning to information on the
  Net. It looks to me like the 18th-century
  endeavour to write an encyclopaedia that contains
  all the knowledge in the world. I am afraid it
  does not work that way. A lot of knowledge, even
  scientific knowledge, cannot be described in a
  logical way. Especially in the arts a lot of
  knowledge is the result of heuristics and
  associative thinking.
• Patel-Schneider and Siméon, Bell Labs Research.
• there is a semantic discontinuity at the very
  bottom of the Semantic Web, interfering with the
  stated goal of the Semantic Web If semantic
  languages do not respect World-Wide Web data,
  then how can the semantic web be an extension of
  the World-Wide Web at all?

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Then its impossible?

• TBL sees the Semantic Web as based upon a whole
  bunch of ontologies mapped together.
• Instead of asking machines to understand
  peoples language, ask people to make the extra
  effort
• It is acknowledged that this is a vast and
  difficult thing to do.
• The tools are not yet there.
• The consensus.
• Its utopian but the main goals are achievable.
• It will be a part of the future web, but never
  all of it.
• Any movement towards it increases the signal to
  noise ratio of the web.
• It should and will be done where it can be.

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Conclusions for Museums

• DigiCULT
• The Semantic Web is a direction, it is like
  North. You go North but you never arrive and say
  here it is.
• Its going to be a large scale, collaborative,
  community thing.
• Requires leadership and opportunity from the
  State.
• We can and should make more starts now.
• There are many valuable steps on the way.

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Further Reading

• Tim Berners-Lee
• BERNERS-LEE,T., J. HENDLER, O. LASSILA The
  Semantic Web A new form of Web content that is
  meaningful to computers will unleash a revolution
  of new possibilities Scientific American, 17 May
  2001.
• http//www.sciam.com/article.cfm?articleID0004814
  4-10D2-1C70-84A9809EC588EF21
• DigiCULT
• Themed Issue 3 Towards a Semantic Web for
  Heritage Resources, May 2003. PDF
• http//www.digicult.info/pages/themiss.php
• Brian Kelly, Introduction to the Semantic Web
  Powerpoint
• More examples and a good introduction to the nuts
  and bolts of RDF (originally for local
  government)
• http//www.ukoln.ac.uk/web-focus/events/conference
  s/lga-2002/

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Thank You