Location-aware technology spawns numerous unforeseen pervasive applications in a wide range of living, pro- duction, commence, and public services. This article provides an overview of the location, localization, and ...Location-aware technology spawns numerous unforeseen pervasive applications in a wide range of living, pro- duction, commence, and public services. This article provides an overview of the location, localization, and localizability issues of wireless ad-hoc and sensor networks. Making data geographically meaningful, location information is essential for many applications, and it deeply aids a number of network functions, such as network routing, topology control, coverage, boundary detection, clustering, etc. We investigate a large body of existing localization approaches with focuses on error control and network localizability, the two rising aspects that attract significant research interests in recent years. Error control aims to alleviate the negative impact of noisy ranging measurement and the error accumulation effect during coope- rative localization process. Network localizability provides theoretical analysis on the performance of localization approaches, providing guidance on network configuration and adjustment. We emphasize the basic principles of localization to under- stand the state-of-the-art and to address directions of future research in the new and largely open areas of location-aware technologies.展开更多
Location k-anonymity techniques typically use anony- mous spatial region to ensure privacy. But these solutions are vul- nerable to multiple queries attacks and inference attacks. Failing to account for the obstacle i...Location k-anonymity techniques typically use anony- mous spatial region to ensure privacy. But these solutions are vul- nerable to multiple queries attacks and inference attacks. Failing to account for the obstacle in geographic space is a severe problem since adversaries will surely regard these constraints. A novel framework is proposed to enhance location-dependent queries, based on the theoretical work of k-anonymity and Voronoi diagrams, allows a user to express service requirement and privacy require- ment by specifying a region and an appropriate value ofk. A trusted anonymity server form a restricted set (k, r, s), which is composed of a number of discrete points to meet the requirements for location k-anonymity and location /-diversity. The location-based services (LBS) server implements an efficient algorithm for continu- ous-region-query processing. Simulation results demonstrated that the framework is superior to previous works in terms of privacy. Moreover, discreteness and randomness of the anonymous set are conducive to resisting location tracking attacks.展开更多
Aimed at the challenges faced by the current urban development and urban planning, along with the research opportunities brought by "big data," this paper proposes an analytical framework based on crowd-sour...Aimed at the challenges faced by the current urban development and urban planning, along with the research opportunities brought by "big data," this paper proposes an analytical framework based on crowd-sourced data for urban planning by reviewing related literature and practice. The framework is mainly oriented towards three major requirements of analysis in urban planning: the physical spaces, the user communities, and the social relationships. This analytical framework can be regarded as a preliminary attempt for future data-intensive applications in urban planning and assessment.展开更多
Aimed at enhancing privacy protection of location-based services( LBS) in mobile Internet environment,an improved privacy scheme of high service quality on the basis of bilinear pairings theory and k-anonymity is pr...Aimed at enhancing privacy protection of location-based services( LBS) in mobile Internet environment,an improved privacy scheme of high service quality on the basis of bilinear pairings theory and k-anonymity is proposed. In circular region of Euclidian distance,mobile terminal evenly generates some false locations,from which half optimal false locations are screened out according to position entropy,location and mapping background information. The anonymity obtains the effective guarantee,so as to realize privacy protection. Through security analyses,the scheme is proved not only to be able to realize such security features as privacy,anonymity and nonforgeability,but also able to resist query tracing attack. And the result of simulation shows that this scheme not only has better evenness in selecting false locations,but also improves efficiency in generating and selecting false nodes.展开更多
文摘Location-aware technology spawns numerous unforeseen pervasive applications in a wide range of living, pro- duction, commence, and public services. This article provides an overview of the location, localization, and localizability issues of wireless ad-hoc and sensor networks. Making data geographically meaningful, location information is essential for many applications, and it deeply aids a number of network functions, such as network routing, topology control, coverage, boundary detection, clustering, etc. We investigate a large body of existing localization approaches with focuses on error control and network localizability, the two rising aspects that attract significant research interests in recent years. Error control aims to alleviate the negative impact of noisy ranging measurement and the error accumulation effect during coope- rative localization process. Network localizability provides theoretical analysis on the performance of localization approaches, providing guidance on network configuration and adjustment. We emphasize the basic principles of localization to under- stand the state-of-the-art and to address directions of future research in the new and largely open areas of location-aware technologies.
文摘动态路网k近邻(kNN)查询是许多基于位置的服务(LBS)中的一个重要问题。针对该问题,提出一种面向动态路网的移动对象分布式kNN查询算法DkNN(Distributed kNN)。首先,将整个路网划分为部署于集群中不同节点中的多个子图;其次,通过并行地搜索查询范围所涉及的子图得到精确的kNN结果;最后,优化查询的搜索过程,引入查询范围剪枝策略和查询终止策略。在4个道路网络数据集上与3种基线算法进行了充分对比和验证。实验结果显示,与TEN~*-Index(Tree dEcomposition based kNN~*Index)算法相比,DkNN算法的查询时间减少了56.8%,路网更新时间降低了3个数量级。DkNN算法可以快速响应动态路网中的kNN查询请求,且在处理路网更新时具有较低的更新成本。
基金Supported by the National Natural Science Foundation of China(61472097)Specialized Research Fund for the Doctoral Program of Higher Education of China(20132304110017)Natural Science Foundation of Heilongjiang Province of China(F2015022)
文摘Location k-anonymity techniques typically use anony- mous spatial region to ensure privacy. But these solutions are vul- nerable to multiple queries attacks and inference attacks. Failing to account for the obstacle in geographic space is a severe problem since adversaries will surely regard these constraints. A novel framework is proposed to enhance location-dependent queries, based on the theoretical work of k-anonymity and Voronoi diagrams, allows a user to express service requirement and privacy require- ment by specifying a region and an appropriate value ofk. A trusted anonymity server form a restricted set (k, r, s), which is composed of a number of discrete points to meet the requirements for location k-anonymity and location /-diversity. The location-based services (LBS) server implements an efficient algorithm for continu- ous-region-query processing. Simulation results demonstrated that the framework is superior to previous works in terms of privacy. Moreover, discreteness and randomness of the anonymous set are conducive to resisting location tracking attacks.
文摘Aimed at the challenges faced by the current urban development and urban planning, along with the research opportunities brought by "big data," this paper proposes an analytical framework based on crowd-sourced data for urban planning by reviewing related literature and practice. The framework is mainly oriented towards three major requirements of analysis in urban planning: the physical spaces, the user communities, and the social relationships. This analytical framework can be regarded as a preliminary attempt for future data-intensive applications in urban planning and assessment.
基金supported by the National Natural Science Foundation of China(61772159,61300124,61300216)the Science and Technology Research Program of Henan Province(172102310677)
文摘Aimed at enhancing privacy protection of location-based services( LBS) in mobile Internet environment,an improved privacy scheme of high service quality on the basis of bilinear pairings theory and k-anonymity is proposed. In circular region of Euclidian distance,mobile terminal evenly generates some false locations,from which half optimal false locations are screened out according to position entropy,location and mapping background information. The anonymity obtains the effective guarantee,so as to realize privacy protection. Through security analyses,the scheme is proved not only to be able to realize such security features as privacy,anonymity and nonforgeability,but also able to resist query tracing attack. And the result of simulation shows that this scheme not only has better evenness in selecting false locations,but also improves efficiency in generating and selecting false nodes.