Method and apparatus for discourse management

• US 6,356,869 B1
• Filed: 04/30/1999
• Issued: 03/12/2002
• Est. Priority Date: 04/30/1999
• Status: Expired due to Term

• Current Assignee: Avaya Incorporated
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Tremblay, Réal R., Chapados, Nicolas, Pateras, Claudia, Stubley, Peter R.
• Primary Examiner(s): Tsang, Fan
• Assistant Examiner(s): Opsasnick, Michael N.
• Application Number:
  US09/302,254
• Time in Patent Office: 1,047 Days
• Field of Search: 704/270, 704/275
• US Class Current: 704/275
• CPC Class Codes: G10L 15/22 Procedures used during a speech recognition process, e.g. man-machine dialogue

Abstract

The invention relates to a system for providing a dialogue enabled speech application system, more particularly to a system apparatus and method for providing a mixed-initiative dialog with a user. The invention provides a discourse manager unit utilizing a dynamic finite-state machine that allows the creation of temporary transitions to accommodate a given context of the conversation without leading to an explosion in the number of finite-state machine states. The invention is particularly useful for use in natural-dialogue speech applications in particular for allowing users to perform actions by simply providing information to the system through spoken request.

Claims

1. A discourse management apparatus, said apparatus comprising:

an input for receiving successively signals representative of information data elements relating to a certain task a user is desirous of achieving;

a processing unit coupled to said input for processing said signals, said processing unit being operative to implement a finite state machine capable to acquire a plurality of functional states linked by transitions, said transitions forming a set;

said processing unit being responsive to an information data element in a first signal applied to said input for enabling a sub-set of said set of transitions;

said processing unit processing an information data element in a second signal applied to said input subsequently to said first signal to cause said finite state machine to evolve by following at least one of said transitions in said sub-set of transitions;

said processing unit having an output, said processing unit being operative to generate a signal having a practical utility in achieving the certain task when the finite state machine evolves to a given state.

2. An apparatus as defined in claim 1, wherein the evolution of said finite state machine in response to said signals applied to said input define a context associated to the certain task.

3. An apparatus as defined in claim 2, wherein said processing unit includes an expectation handling unit for processing the signals applied to the input on the basis of said context to derive context dependent data items.

4. An apparatus as defined in claim 3, wherein said expectation handling unit makes use of a plurality of context dependent remapping rules to generate context dependent data items.

5. An apparatus as defined in claim 3, wherein said processing unit is operative to cause said finite state machine to evolve at least in part on the context dependent data items.

6. An apparatus as defined in claim 4, wherein said processing unit further comprises a prompt generator for generating a prompt signal, said processing unit further including an output for releasing the prompt signal for communication to the user.

7. An apparatus as defined in claim 6, wherein said prompt generator is operative to generate said context dependent remapping rules on the basis of said prompt signal.

8. An apparatus as defined in claim 1, wherein said transition set includes transitions that are permanently enabled.

9. An apparatus as defined in claim 2, wherein said processing unit is operative to cause said finite state machine to evolve at least in part on the basis of context-dependent transition rules.

10. An apparatus as defined in claim 9, wherein said processing unit further comprises a prompt generator for generating a prompt signal, said processing unit further including an output for releasing the prompt signal for communication to the user.

11. An apparatus as defined in claim 10, wherein said prompt generator is operative to generate said context dependent transition rules on the basis of said prompt signal.

12. An apparatus as defined in claim 1, comprising:

a processor;

a computer readable storage medium coupled to said processor, said computer readable storage medium comprising a program element for execution by said processor for implementing said processing unit, said computer readable storage medium comprising a plurality of data storage locations associated to respective functional states for storing data relative to the associated functional state.

13. An apparatus as defined in claim 1, wherein at least some of said functional states are grouped into subsets, functional states in one of said subsets being linked to other functional states by a common wildcard transition.

26. A computerized reservation system comprising the apparatus defined in claim 1.

27. A natural-dialogue speech application system comprising:

an input for receiving a first signal representative of a spoken utterance;

a speech recognition unit for processing the first signal to derive a sequence of word potentially corresponding to the spoken utterance;

a natural language understanding unit being operative to process said sequence of words to derive summary data elements;

a discourse management unit as defined in claim 1.

14. A method for performing discourse management, said method comprising:

receiving successively signals representative of information data elements relating to a certain task a user is desirous of achieving;

implementing a finite state machine capable to acquire a plurality of functional states linked by transitions, said transitions forming a set;

processing an information data element in a first signal applied to said input to enable a sub-set of said set of transitions;

processing an information data element in a second signal applied to said input subsequently to said first signal to cause said finite state machine to evolve by following at least one of said transitions in said sub-set of transitions;

generating an output signal having a practical utility in achieving the certain task when the finite state machine evolves to a given state.

15. A method as defined in claim 14, wherein the evolution of said finite state machine in response to said signals defines a context associated to the certain task.

16. A method as defined in claim 15, further comprising the step of processing the signals on the basis of said context to derive context dependent data items.

17. A method as defined in claim 16, wherein said context dependent data items are derived at least in part on the basis of a plurality of context dependent remapping rules.

18. A method as defined in claim 16, wherein said finite state machine evolves at least in part on the basis of said context dependent data items.

19. A method as defined in claim 17, further comprising the step of generating a prompt signal and releasing the prompt signal for communication to the user.

20. A method as defined in claim 19, further comprising the step of generating said context dependent remapping rules on the basis of said prompt signal.

21. A method as defined in claim 14, wherein said transition set includes transitions that are permanently enabled.

22. A method as defined in claim 15, further comprising the step of causing said finite state machine to evolve at least in part on the basis of context-dependent transition rules.

23. A method as defined in claim 22, further comprising the step of generating a prompt signal and releasing the prompt signal for communication to the user.

24. A method as defined in claim 23, further comprising the step of generating context dependent transition rules on the basis of said prompt signal.

25. A method as defined in claim 14, wherein at least some of said functional states are grouped into subsets, functional states in one of said subsets being linked to other functional states by a common wildcard transition.

28. A discourse management apparatus, said apparatus comprising:

means for receiving successively signals representative of information data elements relating to a certain task a user is desirous of achieving;

processing means coupled to said input for processing said signals, said processing means being operative to implement a finite state machine capable to acquire a plurality of functional states linked by transitions, said transitions forming a set;

said processing means being responsive to an information data element in a first signal for enabling a sub-set of said set of transitions;

said processing means processing an information data element in a second signal received subsequently to said first signal to cause said finite state machine to evolve by following at least one of said transitions in said sub-set of transitions;

said processing means being operative to generate a signal having a practical utility in achieving the certain task when the finite state machine evolves to a given state.