ausblenden:
Schlagwörter:
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Zusammenfassung:
Autonomous, graphically embodied agents are a versatile platform for
information presentation and user interaction. This thesis presents ERIC, a
homogeneous agent framework that can be configured to provide real-time running
commentary on a dynamic environment of many and frequent events. We have
focused on knowledge reasoning with a world model, generating and expressing
affect, and generating coherent natural language, synchronised with nonverbal
modalities. The graphical and TTS output of the agent is provided by commercial
systems.
ERIC is currently implemented to commentate a simulated horse race and a
multiplayer tank combat game. With minimal modification the system is
configurable to provide commentary in any continuous dynamically changing
environment; for example, it could commentate sports matches and computer
games, or play the role of "tourist guide" during a self-guided tour of a city.
An elaborate world model is deduced from limited input by an expert system
implemented as rules in Jess. Natural language is generated using
template-based NLG.
Discourse coherence is maintained by requiring semantic relations between the
forwardlooking and backward-looking centers of successive utterances. The agent
uses a set of causal and belief relations to assign appraisals of
emotion-eliciting conditions to facts in the world model based on goals and
desires. These appraisals are used to generate an affective state according to
the OCC cognitive model of emotions; the agent�s affect is expressed via his
lexical choice, gestures and facial expressions.
ERIC was designed to be domain-independent, homogeneous, behaviourally complex,
reactive and affective. Domain-indepence was evaluated by comparing the effort
required to implement the ERIC system with the effort required to re-implement
the framework for another domain. Complexity, reactivity and affectivity were
assessed by independent experts, whose reviews are presented.