学　术

　　为加强我校各学科之间的学术交流，搭建教师学术交流平台，促进教师学术水平提升和跨学科合作，教师发展中心开展跨学科学术沙龙活动。

　　本次活动教师发展中心特别邀请昆士兰大学的郑凯博士，与我校师生共同探讨数据库研究的前沿热点。具体安排如下，欢迎感兴趣的教师和博士生参加。

　　一、主　题：Interactive Top-k Spatial Keyword Queries　

　　二、主讲人：昆士兰大学 郑凯

　　三、时　间：2016年6月15日（周三）14:30

　　四、地　点：清水河校区主楼B1-104

　　五、主持人：计算机学院 连德富

　　六、承办单位：计算机科学与工程学院

　　七、交流内容：

　　Conventional top-k spatial keyword queries require users to explicitly specify their preferences between spatial proximity and keyword relevance. In this work we investigate how to eliminate this requirement by enhancing the conventional queries with interaction, resulting in Interactive Top-k Spatial Keyword (ITkSK) query. Having confirmed the feasibility by theoretical analysis, we propose a three-phase solution focusing on both effectiveness and efficiency. The first phase substantially narrows down the search space for subsequent phases by efficiently retrieving a set of geo-textual k-skyband objects as the initial candidates. In the second phase three practical strategies for selecting a subset of candidates are developed with the aim of maximizing the expected benefit for learning user preferences at each round of interaction. Finally we discuss how to determine the termination condition automatically and estimate the preference based on the user's feedback. Empirical study based on real PoI datasets verifies our theoretical observation that the quality of top-k results in spatial keyword queries can be greatly improved through only a few rounds of interactions

　　八、主讲人简介：

　　Dr. Kai Zheng is DECRA Researcher at University of Queensland. He received his PhD degree in Computer Science from The University of Queensland in 2012. His research focus is to find effective and efficient solutions for managing, integrating and analyzing big data for business, scientific and personal applications. He has been working in the area of spatial-temporal databases, uncertain databases, trajectory computing, social-media analysis and bioinformatics. He has published over 60 papers in the highly referred journals and conferences such as SIGMOD, ICDE, EDBT, The VLDB Journal, ACM Transactions and IEEE Transactions. He was the Program Committee Chair of the International Workshops on Human Mobility Computing (HuMoComp 2013 & 2014) , and the International Workshop on Big Data Management and Service (BDMS) in 2013. He is on the reviewer board of several top database journals such as IEEE TKDE, ACM TODS, VLDB Journal, KAIS and Geoinformatica. He is on program committee of SIGMOD 2016, SIGMOD 2015, CIKM 2015, CIKM 2014, as well as several other international and regional database conferences.

　　欲参与本次沙龙的教师和博士生，请于2016年6月14日（周二）17:00（限额30人，额满为止）前以邮件形式将本人相关信息（包括姓名、所在单位、移动电话、邮箱、研究方向）发送至cfd@uestc.edu.cn。

　　联系人：袁老师   电话：61830230

　　　　　　　　　　　　　　　　　　人力资源部教师发展中心

　　　　　　　　　　　　　　　　　　　　2016年6月14日