17 research outputs found

    DOI 10.1007/s00778-005-0166-4 REGULAR PAPER

    No full text
    25 January 2006 c ○ Springer-Verlag 2006 Abstract With the continued proliferation of wireless communications and advances in positioning technologies, algorithms for efficiently answering queries about large populations of moving objects are gaining interest. This paper proposes algorithms for k nearest and reverse k nearest neighbor queries on the current and anticipated future positions of points moving continuously in the plane. The former type of query returns k objects nearest to a query object for each time point during a time interval, while the latter returns the objects that have a specified query object as one of their k closest neighbors, again for each time point during a time interval. In addition, algorithms for so-called persistent and continuous variants of these queries are provided. The algorithms are based on the indexing of object positions represented as linear functions of time. The results of empirical performance experiments are reported

    Efficient indexing of the historical, and future positions of moving

    No full text
    Proceedings - Sixth International Conference on Mobile Data Management, MDM'0559-6

    Moving Objects Tracking

    No full text

    An Effective Method to Detect People in Danger

    No full text

    Spatiotemporal Compression Techniques for Moving Point Objects

    Get PDF
    Moving object data handling has received a fair share of attention over recent years in the spatial database community. This is understandable as positioning technology is rapidly making its way into the consumer market, not only through the already ubiquitous cell phone but soon also through small, on-board positioning devices in many means of transport and in other types of portable equipment. It is thus to be expected that all these devices will start to generate an unprecedented data stream of time-stamped positions. Sooner or later, such enormous volumes of data will lead to storage, transmission, computation, and display challenges. Hence, the need for compression techniques.\ud Although previously some work has been done in compression for time series data, this work mainly deals with one-dimensional time series. On the other hand, they are good for short time series and in absence of noise, two characteristics not met by moving objects.\ud We target applications in which present and past positions of objects are important, so focus on the compression of moving object trajectories. The paper applies some older techniques of line generalization, and compares their performance against algorithms that we specifically designed for compressing moving object trajectories

    Indexing the Positions of Continuously Moving Objects

    No full text
    The coming years will witness dramatic advances in wireless communications as well as positioning technologies. As a result, tracking the changing positions of objects capable of continuous movement is becoming increasingly feasible and necessary. The present paper proposes a novel, R # -tree based indexing technique that supports the efficient querying of the current and projected future positions of such moving objects. The technique is capable of indexing objects moving in one-, two-, and three-dimensional space. Update algorithms enable the index to accommodate a dynamic data set, where objects may appear and disappear, and where changes occur in the anticipated positions of existing objects. A comprehensive performance study is reported
    corecore