A new task‐oriented conversational mode speech recognition system

A conversational mode‐connected speech recognition system which simulates the function of an airline ticket agent is described. The system which allows a complete spoken dialog over dialed‐up telephone lines comprises a syntax‐directed dynamic programming temporal alignment algorithm [C. S. Meyers and S. E. Levinson, IEEE Trans. Acoust. Speech Signal Process. ASSP‐30, 561–565 (1982)] for acoustic pattern recognition and a semantic processor [S. E. Levinson and K. L. Shipley, Bell Syst. Tech. J. 59, 119–137 (1980)] that controls an audio response system making two‐way speech communication possible. The system is highly robust and operates on‐line in ten times real time in speaker trained mode (or 60 times in speaker‐independent mode) on a 32‐bit minicomputer/array processor combination. The heterarchical nature of the system allows it some intelligent processing such as the ability to recognize incorrect, incomplete, improbable, and/or conflicting information in the context of the transaction and to pose q...