  We have come to rely on industrial-scale cyber-physical systems more and more
to manage tasks and machinery in safety-critical situations. Efficient,
reliable fault identification and management has become a critical factor in
the design of these increasingly sophisticated and complex devices. Teams of
co-operating software agents are one way to coordinate the flow of diagnostic
information gathered during fault-finding. By wielding domain knowledge of the
software architecture used to construct the system, agents build and refine
their beliefs about the location and root cause of faults. This paper examines
how agents constructed within the GORITE Multi-Agent Framework create and
refine their beliefs. We demonstrate three different belief structures
implemented within our Fault Diagnostic Engine, showing how each supports a
distinct aspect of the agent's reasoning. Using domain knowledge of the IEC
61499 Function Block architecture, agents are able to examine and rigorously
evaluate both individual components and entire subsystems.
