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Uncertain Distance-Based Range Queries over Uncertain moving objects

Journal of Computer Science & Technology 2010年第5期25卷 982-998页

作者：陈逸菲秦小麟刘亮 College of Information Science and Technology Nanjing University of Aeronautics and Astronautics College of Information and Control Nanjing University of Information Science and Technology CCF

Distance-based range search is crucial in many real *** particular,given a database and a query issuer,a distance-based range search retrieves all the objects in the database whose distances from the query issuer are less than or equal to a given ***,due to the accuracy of positioning devices,updating protocols or characteristics of applications（for example,location privacy protection）,data obtained from real world are imprecise or ***, existing approaches over exact databases cannot be directly applied to the uncertain *** this paper,we redefine the distance-based range query in the context of uncertain databases,namely the probabilistic uncertain distance-based range （PUDR） queries,which obtain objects with confidence *** categorize the topological relationships between uncertain objects and uncertain search ranges into six cases and present the probability evaluation in each *** is verified by experiments that our approach outperform Monte-Carlo method utilized in most existing work in precision and time cost for uniform uncertainty *** approach approximates the probabilities of objects following other practical uncertainty distribution,such as Gaussian distribution with acceptable *** the retrieval of a PUDR query requires accessing all the objects in the databases,which is quite costly,we propose spatial pruning and probabilistic pruning techniques to reduce the search *** metrics,false positive rate and false negative rate are introduced to measure the qualities of query *** extensive empirical study has been conducted to demonstrate the efficiency and effectiveness of our proposed algorithms under various experimental settings.

关键词： moving objects uncertainty distance-based range query

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Indexing Future Trajectories of moving objects in a Constrained Network

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Journal of Computer Science & Technology 2007年第2期22卷 245-251页

作者：陈继东孟小峰 School of Information Renmin University of China Beijing 100872 China Key Laboratory of Data Engineering and Knowledge Engineering Ministry of Education Beijing 100872 China

Advances in wireless sensor networks and positioning technologies enable new applications monitoring moving objects. Some of these applications, such as traffic management, require the possibility to query the future trajectories of the objects. In this paper, we propose an original data access method, the ANR-tree, which supports predictive queries. We focus on real life environments, where the objects move within constrained networks, such as vehicles on roads. We introduce a simulation-based prediction model based on graphs of cellular automata, which makes full use of the network constraints and the stochastic traffic behavior. Our technique differs strongly from the linear prediction model, which has low prediction accuracy and requires frequent updates when applied to real traffic with velocity changing frequently. The data structure extends the R-tree with adaptive units which group neighbor objects moving in the similar moving patterns. The predicted movement of the adaptive unit is not given by a single trajectory, but instead by two trajectory bounds based on different assumptions on the traffic conditions and obtained from the simulation. Our experiments, carried on two different datasets, show that the ANR-tree is essentially one order of magnitude more efficient than the TPR-tree, and is much more scalable.

关键词： database spatial database access methods moving objects

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A spatiotemporal algebra in Hadoop for moving objects

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Geo-Spatial Information Science 2018年第2期21卷 102-114页

作者： Mohamed S.Bakli Mahmoud A.Sakr Taysir Hassan A.Soliman Faculty of Computers and Information Assiut UniversityAssiutEgypt Faculty of Computer and Information Sciences Ain Shams UniversityCairoEgypt Universitélibre de Bruxelles BruxellesBelgium

Spatiotemporal data represent the real-world objects that move in geographic space over *** enormous numbers of mobile sensors and location tracking devices continuously produce massive amounts of such *** leads to the need for scalable spatiotemporal data management *** systems shall be capable of representing spatiotemporal data in persistent storage and in *** shall also provide a range of query processing operators that may scale out in a cloud ***,very few researches have been conducted to meet this *** paper proposes a Hadoop extension with a spatiotemporal *** algebra consists of moving object types added as Hadoop native types,and operators on top of *** Hadoop file system has been extended to support parameter passing for files that contain spatiotemporal data,and for operators that can be unary or *** the types and operators are accessible for the MapReduce *** an extension allows users to write Hadoop programs that can perform spatiotemporal *** queries may call more than one operator for different jobs and keep these operators running in *** paper describes the design and implementation of this algebra,and evaluates it using a benchmark that is specific to moving object databases.

关键词： Spatiotemporal algebra Hadoop MapReduce moving objects

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Designing a location update strategy for free-moving and network-constrained objects with varying velocity

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第8期15卷 675-686页

作者： Yuan-Ko HUANG Lien-Fa LIN Department of Information Communication Kao-Yuan University

Spatio-temporal databases aim at appropriately managing moving objects so as to support various types of queries. While much research has been conducted on developing query processing techniques, less effort has been made to address the issue of when and how to update location information of moving objects. Previous work shifts the workload of processing updates to each object which usually has limited CPU and battery capacities. This results in a tremendous processing overhead for each moving object. In this paper, we focus on designing efficient update strategies for two important types of moving objects, free-moving objects(FMOs) and network-constrained objects(NCOs), which are classified based on object movement models. For FMOs, we develop a novel update strategy, namely the FMO update strategy(FMOUS), to explicitly indicate a time point at which the object needs to update location information. As each object knows in advance when to update(meaning that it does not have to continuously check), the processing overhead can be greatly reduced. In addition, the FMO update procedure(FMOUP) is designed to efficiently process the updates issued from moving objects. Similarly, for NCOs, we propose the NCO update strategy(NCOUS) and the NCO update procedure(NCOUP) to inform each object when and how to update location information. Extensive experiments are conducted to demonstrate the effectiveness and efficiency of the proposed update strategies.

关键词： Spatio-temporal databases moving objects Free-moving objects Network-constrained objects

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New Fragile Watermarking Technique to Identify Inserted Video objects Using H.264 and Color Features

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Computers, Materials & Continua 2023年第9期76卷 3075-3096页

作者： Raheem Ogla Eman Shakar Mahmood Rasha I.Ahmed Abdul Monem S.Rahma Computer Science Department University of TechnologyBaghdad11030Iraq Computer Science Department Al_Maarif University CollegeAnbar31001Iraq

The transmission of video content over a network raises various issues relating to copyright authenticity,ethics,legality,and *** protection of copyrighted video content is a significant issue in the video industry,and it is essential to find effective solutions to prevent tampering and modification of digital video content during its transmission through digital ***,there are stillmany unresolved *** paper aims to address those challenges by proposing a new technique for detectingmoving objects in digital videos,which can help prove the credibility of video content by detecting any fake objects inserted by *** proposed technique involves using two methods,the H.264 and the extraction color features methods,to embed and extract watermarks in video *** study tested the performance of the system against various attacks and found it to be *** evaluation was done using different metrics such as Peak-Signal-to-Noise Ratio(PSNR),Mean Squared Error(MSE),Structural Similarity Index Measure(SSIM),Bit Correction Ratio(BCR),and Normalized *** accuracy of identifying moving objects was high,ranging from 96.3%to 98.7%.The system was also able to embed a fragile watermark with a success rate of over 93.65%and had an average capacity of hiding of *** reconstructed video frames had high quality with a PSNR of at least 65.45 dB and SSIMof over 0.97,making them imperceptible to the human *** system also had an acceptable average time difference(T=1.227/s)compared with other state-of-the-art methods.

关键词： Video watermarking fragile digital watermark copyright protection moving objects color image features H.264

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Applied Techniques in Tracking moving Targets in Marine Using Image Processing

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Open Journal of Marine Science 2016年第4期6卷 524-537页

作者： Hossein Kardan Moghaddam Ali Asghar Yarifard Birjand University of Technology Birjand Iran University of Bojnord Bojnord Iran

moving objects tracking is one of the most used categories in the realm of machine vision that has attracted attention of so many researchers in recent decades. Video tracking has various applications in military industries, protective systems and machine vision. Target tracking algorithms vary according to their usages. In this paper, it has been attempted to discuss and analyze mobile target tracking techniques and algorithms in Marine.

关键词： moving objects Tracking Good Features for Track Contour

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一种基于quadtree的移动对象的动态属性索引

一种基于quadtree的移动对象的动态属性索引

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第十八届全国数据库学术会议

作者：丁锐孟小峰中国人民大学信息学院

1.引言近年来无线通讯技术和全球定位技术的迅速发展为移动对象的动态属性(如位置信息)的管理提供了有力的技术支持,也使得基于移动对象之上的应用日益广泛和普及。移动电讯市场的业界人士预期,到2002年将有超过5亿移动手机用户;而到200... 详细信息

1.引言近年来无线通讯技术和全球定位技术的迅速发展为移动对象的动态属性(如位置信息)的管理提供了有力的技术支持,也使得基于移动对象之上的应用日益广泛和普及。移动电讯市场的业界人士预期,到2002年将有超过5亿移动手机用户;而到2004年这个数字将翻番,达到10亿。人们更加期望手机能够成为无

关键词： moving objects Dynamic attributes Quadtree Index Querying process

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An Improved CNN Search Algorithm

An Improved CNN Search Algorithm

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2005年全国理论计算机科学学术年会

作者： CAI Shu-Lan YU Jing ZHANG Zhong-Ping (Department of Computer Science, Yanshan University, Hebei Qinhuangdao 066004)

＜正＞ This paper discusses how to find all split points covered by a new data point, we propose a direct comparison method, which is applied to search single nearest neighbor （NN）of moving objects. Its computation is fewer than the method taken by the continuous NN （CNN） search algorithm. And we also propose a dynamic comparison method, which is applied to search multiple NN of moving objects.

关键词： moving objects Nearest neighbor CNN search

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移动对象管理的自适应索引方法

移动对象管理的自适应索引方法

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第十八届全国数据库学术会议

作者：曹会萍丁治明王珊孟小峰中国人民大学数据与知识工程研究所中国科学院计算技术研究所

1.引言计算技术与无线通讯技术的发展与结合使得一种全新的计算模式一移动计算模式成为了现实。在移动计算模式下,用户使用便携计算机通过无线通讯接口实现对信息网络的访问,而不受实际物理位置变化的影响。在过去的十年里,这种全新的... 详细信息

1.引言计算技术与无线通讯技术的发展与结合使得一种全新的计算模式一移动计算模式成为了现实。在移动计算模式下,用户使用便携计算机通过无线通讯接口实现对信息网络的访问,而不受实际物理位置变化的影响。在过去的十年里,这种全新的计算模式得到了飞速的发展,并在越来越多的领域中发挥了不可替

关键词： Mobile database moving objects Indexing

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改进的CNN搜索算法

改进的CNN搜索算法

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第二十届全国数据库学术会议

作者：刘国华张颖陈子军陈子阳复旦大学计算机信息与技术系燕山大学计算机科学系

1引言最近邻居(nearest neighbor)搜索是空间数据库中最重要的操作之一。传统的最近邻居搜索方法都把查询点看作是静止的。随着无线通讯和追踪移动对象位置技术的发展,如何及时准确地回答移动对象发出的查询请求成为新的研究热点。人们对轨

关键词： moving objects Nearest neighbor search CNN

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