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modify the architecture and underlying knowledge
base design to be appropriate for use in the
healthcare domain.
The term ‘Agora’ originating in Greece, is the
public forum and market place, where people
gathered to discuss politics, news, exchange views
etc. Similarly, agent Agoras are places where the
agents arrive to communicate, negotiate, coordinate,
collaborate and trade information and services
(Matskin et. al. 2001). We have used the Agora
metaphor in the development of a multi-agent
system which consists of a set of interconnected
Agoras and agents. Default agents are attached to an
Agora while the other agents are registered at an
Agora (Matskin et. al. 2001). The Agora system
allows where possible agents to register and present
activities. A matchmaker inside the agora compares
the activities, and if two or more activities match, a
negotiation agent will be started. This negotiation
agent will manage the negotiation between these
agents. The idea is that agents interested in some
topic can find an Agora that operates in the specific
domain, and then receive services and information
through the Agora. The registered agents suggest
that agents that want to "participate" in an Agora
have to be registered first. The agent will then
advertise themselves, and the Agora will help this
agent to find other agents and Agoras that may help
the agent to carry out tasks. Default agents are
agents that are bound to the Agora to perform some
services for the Agora. These agents may be
performing services like negotiation, coordination,
registration, or for example offering access to a
database. It is possible for agents to be registered at
several Agoras and that there could be interrelations
between Agoras (Matskin et. al. 2001).
Agora has been developed using Java, and
JATLite is used as a tool for communication
(Matskin et. al. 2001). Prior research has found that
it possible to run more than 70 agents concurrently
on the JATLite router. KQML is used as the basic
external communication language and protocol for
exchanging information and knowledge. A separate
communication format Message Wrapper has been
defined inside the agents and Agoras. Between the
internal format and the external KQML language
there is a translator. We are now using this translator
to use FIPA instead of KQML, by building a new
FIPA translator.
3.1 Using AGORA for facilitating
evidence-based heath care
The main advantage with the Agora approach is that
the agents have rather simple implementations
because of the gathering of specially designed
services and functionality inside the Agoras. In such
an application agents will represent the clinicians,
the case events and the evidence based medicine
service providers. In order to implement a virtual
health care Agora we first identify participants of the
cooperative work. We are interested in the roles
specific agents will undertake.
• Clinician agent - represents the medical
professional, at this point of time we only
consider practitioners of medicine who undertake
clinical work.
• Active case agent – represents a clinical case
currently under care
• Completed case agent – represents published
clinical case reports
• Case manager agent – a coordinator of cases and
clinicians in a health care environment.
• Diagnosis negotiation assistant agent –
matchmaking active case with other cases
• Cochrane library collaborator agent – manager of
the agents representing specific health domains.
Cooperative points for agents work in the health care
domain can be identified, as follows:
• Coordination of the health care activity
• Coordination of different clinician agents
• Coordination (information gathering) and
diagnosis support between a case manager agent
and the Cochrane library agents.
These cooperative points can be mapped into the
following set of agoras: a clinician agora, a case
agora, a diagnosis agora and a cochrane
collaboration agora.
Agora represents both registered and default
agents (refer Figure 2). Registered agents are either:
coordination agents, negotiation agents or
participant agents. The first two types of agents
manage coordination and negotiation activities to be
performed at the corresponding Agora. The
participant agents represent participants of the
cooperative activity. The default agents in Agora are
the Agora manager, service and matchmaking
agents. Each participant agent (for example case
agent) presents offers and requests for information.
Offered activity (OA) may be any activity the agent
can perform by itself, for example in the heath care
domain an offered activity could diagnosis
information offered by the diagnosis assistant agent.
Interrelations and connections among agents and
Agoras are depicted at Figure 2. Lines between
Agoras mean that agents from connected Agoras can
be registered on both of them. Each Agora is
shadowed as there is more than one Agora of each
type. The coordination agents manage corresponding
protocols.
AN AGENT-BASED INFRASTRUCTURE FOR FACILITATING EVIDENCE BASED MEDICINE
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