中文摘要：

如何利用时间信息改善Web搜索效果是近年来的一个研究热点,这是因为大多数的Web网页都包含有时间信息,同时许多Web查询也含有时间查询词.文中围绕时间感知的Web搜索需求,重点研究了两个方面的问题,即查询时间词扩展和时间感知的搜索结果排序,提出了基于查询词和时间词共现关系的查询时间词扩展算法,以及结合了文本相关度和时间相关度的时间感知排序算法.作者建立了一个时间感知的Web搜索原型系统,并在大规模真实数据集上进行了实验.实验结果表明作者提出的算法在搜索效果上有明显的改善,并且具有较好的时间性能.

英文摘要：

Utilizing time information to improve the effective of Web search has been a research focus in recent years,because most Web pages contain time information and many Web queries involve time-related query terms.Motivated by the needs of time-aware Web search,in this paper,we concentrate on two key issues,namely temporal keyword expansion and time-aware ranking.Particularly,we propose a new algorithm for temporal word expansion which is based on the co-occurrence of query terms and time words.In addition,we present a new time-aware ranking algorithm considering both textual relevance and time relevance.We build a prototype system and conduct experiments on real data sets to evaluate the performance of our proposal.The results show that the proposed algorithms are time efficient and have a substantial improvement on the effective of Web search.