The project focused on the re-design of the multi-agent architecture developed within the SETA project to build adaptive
Web based systems.
This architecture represents an evolution of the SETA architecture and differs for the internal design of the system agents.
In INTRIGUE (INteractive TouRist Information GUidE), an agent-communication infrastructure has been developed to enable a uniform
communication among heteregeneous agents, which can communicate in synchronous and asynchronous ways. This infrastructure supports the
design of internal agent architectures which can behave according to different paradigms: they can offer services by method execution,
in a pure Object-Oriented style, but they can also carry on internal activities in an autonomous way.
The basic principles behind the design are:
the identification of roles needed to offer the main functionalities of the system;
the definition of agents for these roles;
management of the interaction between the agents.
A set of specialized agents have been defined. Each of them has a key role (for instance, the communication with the Web,
page generation, etc.) and manages the related activities, using knowledge and technologies specific to the task.
In particular the architecture includes:
an agent managing the interaction with the user from a logical stand point, allowing the system to decide the next
step of the interaction based on context of the previous interaction and on the user requests;
a set of specialized agents for the user modeling, the selection of information to present and the Web page generation;
some agents with inference capabilities to decompose and solve complex problems.
The activity of the project involved also the definition of the internal architecture of a single agent. This architecture
has been designed to allow the interaction of heterogeneous agents and includes a wrapper to allow a unified message protocol
between differend kind of agents. The protocol includes syncronous, asyncronous and multicast types of messages. Moreover, the
wrapper allows the agents to manage requests in parallel using the Java thread mechanism. Internally the agents can follow
different paradigms: action-based or standard Java objects. The User Modeling component needs to provide user data to other
agents but also has some autonomous activities to carry on such as revising the user model, during the interaction with the
system: these activities should be managed indipendently from the other agents requests. Other agents, like the Personaliation
Agent, responsible for building the personalized Web pages, should respond to requests from the browser.
A prototype for personalized tourism services on the Web has been build following the revised architecture. The system
presents to the user artistic attractions as well as restaurants or other useful services. The navigation of the touristic
site can be done on the basis of different criteria: information can be found geographically or searching by categories
(museums, buildings, restaurants, etc.) or combining the two strategies, for example the user can search for all the Baroque
buildings in Torino.
INTRIGUE tailors the suggestion of touristic attractions to the user's interests and requirements, taking into account the
fact that, in addition to individual users, also groups of people might want to plan a trip together. In order to handle this
issue, the system maintains a model of the group of tourists and tailors the suggestions to the requirements of the possibly
heterogeneous (e.g., the group might include people having extremely different requirements, such as audults, children,
disabled people). The system also offers specific problem-solving functionalities to coordinate the visit to the suggested
places, recommending visits during the opening times of the various places.
The system has reasoning capabilities since it is able to schedule the visit during a day by taking into account both the
user's choices and other constraints. In particular, the system allows the user to select and insert in the agenda a set of
artistic attractions of interest and ask the system to organize the plan of the day on the basis of the selected items and
other constraints the user might have (for example the starting time of the visit, morning or afternoon preferences).
L. Ardissono, A. Goy, G. Petrone, M. Segnan, P. Torasso "Tailoring the recommendation of
tourist information to heterogeneous user groups", Proc. of Third Workshop on Adaptive Hypertext
and Hypermedia (AH2001), Aarhus, Denmark, August 2001
For more information about this project, please