A network model dealing with focus of conversation for speech understanding system

A new network model is proposed by introducing a special node called ε-node. This model makes flexible path weight control of the network representing the acceptable sentences (ASN) possible by giving a score to the ε-node. The path weight control strategy is developed using a rule based system, which has the ability to provide an adequate ASN according to the flow of conversation. Furthermore, a state transition network based system is adopted in order to follow and adapt to the changing topics of the conversation. Thus, a high speed and high reliable conversational speech understanding system is realized.