Patent ID: 7949531
Filing Date: 2011-05-24
Classification: G06F,G10L

Abstract:
1. A conversation controller configured to output a reply sentence according to a user utterance, comprising: a plan memory unit comprising a memory, the plan memory unit storing a plurality of plans, wherein each plan has a reply sentence and one or more pieces of next candidate designation information for designating a next candidate reply sentence to be output following the reply sentence; a plan conversation unit comprising a processor, the plan conversation unit: a discourse space conversation unit that outputs a reply sentence about a topic which is not related to the withheld next candidate reply sentence according to the second user utterance; a morpheme extracting unit that extracts, based on a character string corresponding to the second user utterance, at least one morpheme comprising a minimum unit of the character string, as first morpheme information; and a conversation database that stores: wherein the discourse space conversation unit comprises: a topic identification information retrieval portion that compares, based on first morpheme information extracted by the morpheme extracting unit, the first morpheme information with the plurality of pieces of topic identification information, and when the topic identification information retrieval portion retrieves topic identification information including a part of the first morpheme information from among the plurality of pieces of topic identification information and the retrieved topic identification information includes second morpheme information including a part of the first morpheme information, the topic identification information retrieval portion outputs the second morpheme information to the reply retrieval portion; an elliptical sentence supplementation portion that, when the retrieved topic identification information does not include second morpheme information including a part of the first morpheme information, adds topic identification information previously retrieved by the topic identification information retrieval portion to the first morpheme information to provide supplemented first morpheme information; a topic retrieval portion that, compares the supplemented first morpheme information with one or more pieces of second morpheme information associated with the retrieved topic identification information, retrieves second morpheme information associated with the retrieved topic identification information including a part of the supplemented first morpheme information from among the one or more pieces of second morpheme information and out puts the retrieved second morpheme information to the reply retrieval portion; and a reply retrieval portion that retrieves, based on the second morpheme information from one of the topic identification information retrieval portion and the topic retrieval portion, a reply sentence associated with the retrieved second morpheme information, wherein some plans have a plurality of reply sentences into which one explanatory sentence is divided.