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In-Depth Information
provider drops out or e.g. cannot fulfill the required quality of service, a new
service provider can be determined by retrieving a list of candidate services
from the GSP and selecting the best service using the Contract Net Protocol.
The focus of ISReal is the design of agents and multiagent systems in a virtual
reality settings where the agents represented by avatars that form their virtual
bodies. Digital factories are one of the application areas ISReal is aiming at.
The aim of the ISReal project is to develop an execution platform for semantic
3D simulations [8]. The basic idea of ISReal is to add semantic descriptions
to 3D objects and specify their functionality by semantic service descriptions.
Our approach is based on the semantic Web standards OWL
9
,OWL-S
10
,and
RDFA
11
. Agents perceive the annotated facts and service descriptions and use
them for reasoning and planning. The scene runs in a 3D-enabled Web browser
based on XML3D
12
. We use our model-driven development environment DDE
for engineering the agents that control the avatars (their virtual body) in the
3D scene. Figure 14 depicts the application of an agent interaction protocol in
a 3D simulation. Agent
A1
's target is to buy ingredients for the production of
some pills on the pill filling machine shown in the background. The Contract
Net Protocol is used by agent
A1
to negotiate with the pharmacy agents
A3
,
A4
,and
A5
. In Figure 14, agent
A5
won the auction.
Fig. 14.
Contract Net example in the ISReal scenario
6 Related Work
Communication is an important aspect of agent-based and multiagent systems
and therefore has been intensively investigated. The FIPA
13
initiative was origi-
nally founded to produce specifications for software standards for heterogeneous
and interacting agents and agent-based systems. One of the main achievements of
13
www.fipa.org
