OAS'03 Challenge Problem
The problem domain defined below was developed for the ontology tool
assessment exercise organised by the EU OntoWeb project (SIG on
Enterprise-Standard ontology environments) and is adapted here with
their permission.
A challenge paper for OAS'03 should describe the design and
(preferably) an implementation of a multi-agent system in that domain.
The system described should comprise two or more agents that use a
declarative agent communication language to request information and
services from each other, based on publicly advertised ontologies,
interaction protocols, and any other explicitly represented
information required to achieve meaningful communication in an open
environment. Of particular interest are the ways in which ontological
information is referenced, accessed and used by agents. Your paper
should clearly state, for each agent, any assumptions that are
hardcoded into it regarding the communication mechanisms, structure
and abilities of the other agents.
Note that the focus of this challenge is not on the ontology itself,
but on how it is used during the process of design, implementation and
execution of your agent-based application in this domain. Therefore,
it is not necessary to have used in your application (or defined in
your ontology) all features discussed in the domain specification
below. You are free to describe an application that addresses a
subset of this domain.
Problem domain specification
Suppose you are in charge of developing an agent-based application for
a travel agent in New York. The principal concepts the travel agent
must deal with are modes of travel (restricted to plane, train, ferry,
motorbike or ship) and accommodation options (restricted to hotels and
bed and breakfast providers).
The travel agency is specially interested in flights, as it is the
means of transport mostly used by its customers. In fact, customers
are usually interested in the kind of planes that they will fly on: Is
it a Boeing, or is it an Airbus? Furthermore, they are even
interested in the specific model of the plane in which they will fly
(e.g. a Boeing 717 or a Boeing 777 - see this
link for an example description of a particular model of
plane). Each model of transport belongs only to one kind of
transportation (e.g., it can be only a plane, or a bus, or a car,
etc.). For each flight, the agency knows the arrival date, the
departure date, the arrival city, the departure city, the arrival
airport, the departure airport, the prices for first class, business
class and economy class seats, the departure time and arrival time.
Time and date will be considered as absolute date.
As for the destinations of customers' travels, they are diverse. Some
customers ask for trips to the Statue of Liberty in New York; other
ask for trips to Washington, San Francisco, Seattle. There are
customers interested in visiting Europe: the most common destinations
are London, Paris (either the city or Disneyland Paris) and
Madrid. Others are interested in other places, such as Cairo (Egypt).
The client can use the following transport to move inside the city:
underground, city buses, taxis, and rental cars.
Hotels rank from 1 star hotels to 5 star hotels and each hotel belongs
to one of these five categories. For all of them, the agency knows
their facilities: address, telephone number, URL, capacity, number of
rooms, available rooms, descriptions, whether dogs are allowed,
distance to the beach, distance to ski fields, etc. The agency also
knows the facilities of the rooms: number of beds, rates, availability
of a TV, Internet connectivity, etc.
There are also some common sense constraints that might usefully be
included in an ontology for this domain, and may possibly be used for
deduction inside the system. For instance, it is not possible to go
from America to Europe by train, car, bike or motorbike. Having this
information in our system will avoid it to search for possible
itineraries using these means of transport when a customer wants to
travel to Europe. Another example of this kind of constraint may be
related to the distance between the origin and destination of a trip
and the available means of transport. If distance betyouen two cities
is between 400 and 800 miles, and there is no airport close to one of
them, the customer will prefer going by car or by train. The customer
also prefers to go by car or train if he hates travel by
plane. Distances can be either in km or miles.
Finally, the system needs to be able to represent knowledge about a
concrete trip. For example: John is travelling from Madrid to NY on
April 5th, 2003 to see the Statue of Liberty and continuing on to
Washington on April 11th. He plans to return to Madrid on April
15th. He has selected two hotels belonging to the Holiday Inn chain in
New York and Washington.
Sample ontology definition
Here is an ontology in RDF
Schema for the above problem domain, developed by Oscar Corcho,
Mariano Fernandez-Lopez and Asunción Gómez-Pérez
from the Universidad Politécnica de Madrid (UPM) and made
available here with their permission.
There is also a generic language-independent version of this ontology
available via the webode ontology editor at UPM. The editor can
export the ontology in a number of different ontology modelling
languages. Anybody interested in using webode for this purpose can
email Oscar Corcho at ocorcho@fi.upm.es for further details.
NOTE: It is not required to use the Madrid ontology
for this challenge problem. It is provided here solely as a possible
resource that you may choose to use. If you prefer you may define
your own ontology for the challenge problem domain.