时空众包数据管理技术研究综述

近年来,众包为传统数据管理提供了一种通过汇聚群体智慧求解问题的新模式,并成为当前数据库领域的研究热点之一.特别是随着移动互联网技术与共享经济模式的快速发展,众包技术已融入到各类具有时空数据的应用场景中,例如各类O2O(online-to-offline)应用、实时交通监控与动态物流管理等.简言之,这种应用众包技术处理时空数据的方式称为时空众包数据管理.对近期在时空众包数据管理方面的研究工作进行综述,首先阐述了时空众包的概念,解释了其与传统众包技术的关系,并介绍了各类典型的时空众包应用;随后描述了时空众包应用平台的工作流程及其任务特点;然后讨论了时空众包数据管理的3项核心研究问题和3类应用技术;最后,总结了时空众包数据管理技术的研究现状并展望了其未来潜在的研究方向,为相关研究人员提供了有价值的参考.In recent years, crowdsourcing, which utilizes the intelligence of crowds to solve problems, provides a novel data processing paradigm for traditional data management challenges and has become one of the hottest research topics. In particular, due to the rapid development of mobile Internet and sharing economy, crowdsourcing not only becomes a new approach for data collection, but is also integrated into all kinds of application scenarios especially spatiotemporal data management such as online-to-offline (O2O) applications, real-time traffic monitoring, and logistics management. In this paper, a survey is provided on existing research of spatiotemporal crowdsourcing. First of all, the concept and representative applications of spatiotemporal crowdsourcing is described, and its relationship with traditional crowdsourcing is explained. Then, the workflow of spatiotemporal crowdsourcing is illustrated. Furthermore, three core research problems and three categories of techniques of spatiotemporal crowdsourcing are discussed. Finally, the state-of-the-art studies of spatiotemporal crowdsourcing are summarized and promising future research directions for the research community are presented. © Copyright 2017, Institute of Software, the Chinese Academy of Sciences. All rights reserved

跨信任域的联邦k-支配Skyline查询算法

k-支配Skyline查询是一种主流的Skyline查询变种，其在多目标决策与推荐领域有着广泛的应用。随着这些应用规模不断扩大，在由多个参与方组成的数据联邦中进行跨域k-支配Skyline查询的需求日益旺盛。然而，由于数据联邦中的参与方之间彼此不互信，进行跨信任域的查询计算需引入大量安全操作，效率较低。为此提出了一种基于跨域隐私向量聚合的算法，从而实现高效的联邦k-支配Skyline查询，并运用一种密文压缩技术进一步优化查询效率，最后通过充分的实验验证了所提方案的优越性