A study on content summarization for large spoken documents and content retrieval through spoken dialogue

为了开发一个面向开放领域口语文档检索的准确的大词汇量连续语音识别系统，我们提出了一种并行使用两种搜索算法的搜索方法，以实现高效和准确的解码。我们对这种新的搜索算法进行了评估，在不增加计算代价的情况下，识别性能得到了显着的提高。我们还提出了将机器学习技术应用于组合多个LVCSR模型的输出的任务。与罗孚等投票方案相比，所提出的技术具有优势，特别是在大多数参与模型不可靠的情况下。通过使用该技术，我们完成了语音驱动的Web检索任务，提高了语音查询的语音识别准确率，从而提高了语音驱动的Web检索的准确率。为此，我们研究了语言表层信息与人类结果之间的关系，得到了有用的表层语言信息。接下来，我们根据这些信息对口语讲座进行了总结，并将其与人类的结果进行了比较。结果，我们得到了与人的结果相当的更好的F-测度和k值。我们在一个口语对话系统中开发了一个可移植的语音识别模块和一个翻译模块。此外，我们还开发了一个对话策略设计工具，并将其应用于富士山观光指南检索、文献检索和酒店预订检索，验证了该工具的实用性。

To develop an accurate large vocabulary continuous speech recognition system for spoken document retrieval in open domain, we proposed a search method using two search algorithms in parallel to achieve efficient and accurate decoding. We evaluated this new search algorithm and obtained significant improvement of recognition performance without severe increase of computational cost We also proposed to apply machine learning techniques to the task of combining outputs of multiple LVCSR models. The proposed technique had advantages over that by voting schemes such as ROVER, especially when the majority of participating models are not reliable. By using this technique, we performed a speech-driven Web retrieval task and improved speech recognition accuracy of spoken queries and then improved retrieval accuracy in speech driven Web retrieval We tried the summarization of spoken lectures. For this purpose, we investigated relations between linguistic surface information and human's results, and we obtained useful surface linguistic information. Next, we summarized spoken lectures based on this information, and compared them with human's results. As a result, we obtained a better F-measure and k-value comparable with human's results. We have developed a portable speech recognition module and an interpreter module in a spoken dialogue system. Furthermore, we also developed a dialogue strategy design tool, applied it to Mt.Fuji sightseeing guidance retrieval, literature retrieval and hotel reservation retrieval and then confirmed the usefulness.