Automated Reasoning and AI Programming

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Automated Reasoning and AI Programming

• Pablo Romero
• pablor_at_sussex.ac.uk
• www.informatics.sussex.ac.uk/users/juanr
• Course Website
• http//www.informatics.sussex.ac.uk/courses/araip/
  summer08

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Course overview

• Basic introduction to Ontology Development
• Lecture
• Monday 12.00 am - 12.50 am CHI-002/3
• Seminars
• Tuesday 11.00 am - 12.50 am (CHI-204/5)
• Thursday 9.00 am - 10.50 am (CHI-002/3)
• Office hour
• Mondays 2.00 pm -3.00 pm (Pev. 3C12)

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This lecture

• What is the semantic web, ontologies and ontology
  languages
• Course structure
• Outline
• Course admin
• Assignment
• The Protégé ontology development environment

4
From spring to summer

• Classic AI (route finding, problem solving, etc.)
• Knowledge representation using logic
• Propositional logic
• First order logic
• Current application of this (semantic web)

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Not yet a semantic web
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(No Transcript)
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Tasks for the semantic web

• Participate in auction bid to buy black leather
  converse trainers new, size 9 but dont pay more
  than 10.00

8
Tasks for the semantic web

• Buy the book Ontology and the semantic web by
  Robert Colomb with the best price but that can be
  delivered by the second week of term

9
Tasks for the semantic web

• Book me a holiday next weekend somewhere warm,
  not too far away, and where they speak French or
  English

10
What is the Problem?

• Markup consists of
• rendering information (e.g., font size and
  colour)
• Hyper-links to related content
• Semantic content is accessible to humans but not
  (easily) to computers

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What information can we see
WWW2002 The eleventh international world wide web
conference Sheraton waikiki hotel Honolulu,
hawaii, USA 7-11 may 2002 1 location 5 days learn
interact Registered participants coming
from australia, canada, chile denmark, france,
germany, ghana, hong kong, india, ireland, italy,
japan, malta, new zealand, the netherlands,
norway, singapore, switzerland, the united
kingdom, the united states, vietnam,
zaire Register now On the 7th May Honolulu will
provide the backdrop of the eleventh
international world wide web conference. This
prestigious event Speakers confirmed Tim
berners-lee Tim is the well known inventor of
the Web, Ian Foster Ian is the pioneer of the
Grid, the next generation internet
12
What can a machine see
WWW2002 The eleventh international world wide web
conference Sheraton waikiki hotel Honolulu,
hawaii, USA 7-11 may 2002 1 location 5 days learn
interact Registered participants coming
from australia, canada, chile denmark, france,
germany, ghana, hong kong, india, ireland, italy,
japan, malta, new zealand, the netherlands,
norway, singapore, switzerland, the united
kingdom, the united states, vietnam,
zaire Register now On the 7th May Honolulu will
provide the backdrop of the eleventh
international world wide web conference. This
prestigious event Speakers confirmed Tim
berners-lee Tim is the well known inventor of
the Web, Ian Foster Ian is the pioneer of the
Grid, the next generation internet
13
Solution XML markup with meaningful tags?
ltnamegtWWW2002 The eleventh international world
wide webconlt/namegt ltlocationgtSheraton waikiki
hotel Honolulu, hawaii, USAlt/locationgt ltdategt7-11
may 2002lt/dategt ltslogangt1 location 5 days learn
interactlt/slogangt ltparticipantsgtRegistered
participants coming from australia, canada, chile
denmark, france, germany, ghana, hong kong,
india, ireland, italy, japan, malta, new zealand,
the netherlands, norway, singapore, switzerland,
the united kingdom, the united states, vietnam,
zairelt/participantsgt ltintroductiongtRegister
now On the 7th May Honolulu will provide the
backdrop of the eleventh international world wide
web conference. This prestigious event Speakers
confirmedlt/introductiongt ltspeakergtTim
berners-leelt/speakergt ltbiogtTim is the well known
inventor of the Web,lt/biogt
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But What About
ltconfgtWWW2002 The eleventh international world
wide webconlt/confgt ltplacegtSheraton waikiki
hotel Honolulu, hawaii, USAlt/placegt ltdategt7-11
may 2002lt/dategt ltslogangt1 location 5 days learn
interactlt/slogangt ltparticipantsgtRegistered
participants coming from australia, canada, chile
denmark, france, germany, ghana, hong kong,
india, ireland, italy, japan, malta, new zealand,
the netherlands, norway, singapore, switzerland,
the united kingdom, the united states, vietnam,
zairelt/participantsgt ltintroductiongtRegister
now On the 7th May Honolulu will provide the
backdrop of the eleventh international world wide
web conference. This prestigious event Speakers
confirmedlt/introductiongt ltspeakergtTim
berners-leelt/speakergt ltbiogtTim is the well known
inventor of the Web,
15
Machine sees
ltnamegtWWW2002 The eleventh international world
wide webclt/namegt ltlocationgtSheraton waikiki
hotel Honolulu, hawaii, USAlt/locationgt ltdategt7-11
may 2002lt/dategt ltslogangt1 location 5 days learn
interactlt/slogangt ltparticipantsgtRegistered
participants coming from australia, canada, chile
denmark, france, germany, ghana, hong kong,
india, ireland, italy, japan, malta, new zealand,
the netherlands, norway, singapore, switzerland,
the united kingdom, the united states, vietnam,
zairelt/participantsgt ltintroductiongtRegister
now On the 7th May Honolulu will provide the
backdrop of the eleventh international world wide
web conference. This prestigious event Speakers
confirmedlt/introductiongt ltspeakergtTim
berners-leelt/speakergt ltbiogtTim is the well known
inventor of the Wlt/biogt ltspeakergtIan
Fosterlt/speakergt ltbiogtIan is the pioneer of the
Grid, the nelt/biogt
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Need to Add Semantics

• External agreement on meaning of annotations
• E.g., Dublin Core
• Agree on the meaning of a set of annotation tags
• Problems with this approach
• Inflexible
• Limited number of things can be expressed
• Use Ontologies to specify meaning of annotations
• Ontologies provide a vocabulary of terms
• Meaning (semantics) of such terms is formally
  specified
• Can also specify relationships between terms in
  multiple ontologies

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Ontology

• Ontology in Philosophy
• Science of Being (Aristotle, Metaphysics, IV, 1)
• What characterizes being?
• What is being?
• In Computer Science
• An engineering artifact
• A specific vocabulary used to describe a certain
  reality, plus
• A set of explicit assumptions regarding the
  intended meaning of the vocabulary
• An explicit, formal specification of a
  conceptualisation

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Structure of an Ontology

• Names for important concepts in the domain
• Elephant is a concept whose members are a kind of
  animal
• Herbivore is a concept whose members are exactly
  those animals who eat only plants or parts of
  plants
• Background knowledge/constraints on the domain
• AdultElephants weigh at least 2,000 kg
• All Elephants are either AfricanElephants or
  IndianElephants
• No individual can be both a Herbivore and a
  Carnivore
• Individuals

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A Semantic Web First Steps

• Make web resources more accessible to automated
  processes
• Extend existing rendering markup with semantic
  markup
• Metadata annotations that describe
  content/function of web accessible resources
• Use Ontologies to provide vocabulary for
  annotations
• Formal specification accessible to machines
• In a standard language based on HTML and XML

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Course outline

• Ontology development
• Protégé as an ontology development environment
• Classes
• Properties
• Domains and ranges
• Property restrictions
• Individuals
• The OWL Web Ontology Language
• XML and RDF
• OWL versions
• Basic syntax

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The course project

• Hands-on course centred around a project
• To develop an ontology
• Individual but whole seminar group will work
  towards a common semantic web service
• Only assignment of the course, submitted on
  Thursday of week 6, worth 25 of total course mark

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Chloe has just finished her undergraduate studies
and is going on holidays for three months at the
end of July. She is planning to visit several
countries in Central and South America. She is
not completely sure about the cities and places
she wants to visit but would like them to provide
for a mixture of beach and cultural (museums,
archeological sites) holidays. She uses the
online flexible travel computational agent for
suggestions of which places to visit, possible
travel companions, a sensible route to follow as
well as for information regarding booking travel,
accommodation, tickets for special events, etc.
First she has to register filling in a profile to
tell the agent about general details (name, date
of birth, gender, etc.) as well as travel
preferences (transport and accommodation
preferences, preferred types of holidays, travel
companion preferences, etc.). After registering
she submits a query to find out about travel
suggestions for the specific countries to visit
and dates of travel. The system returns a list
of possible itineraries. Each itinerary
comprises, besides a sensible route to follow
with suggested staying periods for each place, a
list of possible travel companions for each part
of the journey, suggested transport arrangements,
activities, events and places to visit. Chloe
then marks a subset of the itineraries as
acceptable. After this the agent negotiates and
agrees with the companions agents a definitive
itinerary. The system keeps a record of the
itinerary so that the agent can be queried at any
moment about specific details of the travel plan
(for example to produce a list of suggested
places to eat at a specific city taking into
account the dietary preferences of Chloe and her
companions for that part of the journey)
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Example itinerary

• Itinerary 1
• 30 July. Fly BA0243 (British Airways) from
  Heathrow at 1405 arrive 1915 in Mexico City
• 31 July - 3 August. Stay in Mexico City.
• Accommodation. Gran Hotel Ciudad de Mexico.
• Companions. Emily Brontë, Blaise Pascal
• Suggested activities
• 3 August. Bus to Oaxaca, Mexico
• 3 August - 7 August. Stay in Oaxaca
• Accommodation. Casa Oaxaca
• Companions. Emily Brontë, Giacomo Puccini
• Suggested activities

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Flexible travel computational agent

• Mixture of
• Travel companion
• http//www.travel-companion.net/
• Travel plan organiser
• http//www.tripit.com/
• Flight booking
• http//www.travelocity.co.uk
• Map information
• http//www.mapquest.com/
• And more

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Knowledge needed

• Planning itinerary
• Matching companions
• International transport
• Countries
• Transport within a country
• Cities
• Transport within a city
• Maps
• Accommodation
• Food outlets
• Cultural events
• Shopping
• Tourist attractions

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Course plan
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Reading resources

• Colomb, R. 2007. Ontology and the semantic web.
  IOS Press.
• Lee W. L. 2005. Owl Representing Information
  Using the Web Ontology Language. Trafford.
• Protégé-OWL tutorial
• http//www.co-ode.org/resources/tutorials/ProtegeO
  WLTutorial-p4.0.pdf
• OWL guide
• http//www.w3.org/TR/owl-guide/
• Ontology engineering methodology
• http//www-ksl.stanford.edu/people/dlm/papers/onto
  logy-tutorial-noy-mcguinness.pdf

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Ontology Development Tools

• Ontology languages
• OWL (Web Ontology Language)
• RDF
• XML
• UML
• DAMLOIL
• Ontology Development Environments
• Protégé
• OntoEdit
• Chimaera
• Ontology Servers
• Publishing, version control, management of
  imported ontologies, syntax validation, editing
  tools.

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Protégé

• Allows users to create OWL ontologies without
  writing a single line of code
• Creation of
• Classes
• Properties
• Restrictions
• Individuals
• Queries

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Key points

• Ontologies and the semantic web are current
  applications of Knowledge Representation
• Semantic web would enable online applications to
  do more sophisticated tasks
• OWL is the W3C recommended ontology language
• Protégé allows us to create OWL ontologies
  interactively