Theory of linear and integer programming
Theory of linear and integer programming
The input/output complexity of sorting and related problems
Communications of the ACM
The R*-tree: an efficient and robust access method for points and rectangles
SIGMOD '90 Proceedings of the 1990 ACM SIGMOD international conference on Management of data
Discrete & Computational Geometry - Special issue on ACM symposium on computational geometry, North Conway
Database system issues in nomadic computing
SIGMOD '93 Proceedings of the 1993 ACM SIGMOD international conference on Management of data
CIKM '93 Proceedings of the second international conference on Information and knowledge management
The time index+: an incremental access structure for temporal databases
CIKM '94 Proceedings of the third international conference on Information and knowledge management
Processing queries by linear constraints
PODS '97 Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Efficient searching with linear constraints
PODS '98 Proceedings of the seventeenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Multidimensional access methods
ACM Computing Surveys (CSUR)
PODS '99 Proceedings of the eighteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Comparison of access methods for time-evolving data
ACM Computing Surveys (CSUR)
Indexing moving points (extended abstract)
PODS '00 Proceedings of the nineteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Indexing the positions of continuously moving objects
SIGMOD '00 Proceedings of the 2000 ACM SIGMOD international conference on Management of data
R-trees: a dynamic index structure for spatial searching
SIGMOD '84 Proceedings of the 1984 ACM SIGMOD international conference on Management of data
An Efficient Indexing Scheme for Multi-dimensional Moving Objects
ICDT '03 Proceedings of the 9th International Conference on Database Theory
VLDB '90 Proceedings of the 16th International Conference on Very Large Data Bases
Lower Bounds on the Complexity of Simplex Range Reporting on a Pointer Machine
ICALP '92 Proceedings of the 19th International Colloquium on Automata, Languages and Programming
An efficient information access scheme for mobile objects
IRI'09 Proceedings of the 10th IEEE international conference on Information Reuse & Integration
Hi-index | 0.01 |
We consider the problem of indexing a set of objects moving in d-dimensional spaces along linear trajectories. A simple external-memory indexing scheme is proposed to efficiently answer general range queries. The following are examples of the queries that can be answered by the proposed method: report all moving objects that will (i) pass between two given points within a specified time interval; (ii) become within a given distance from some or all of a given set of other moving objects. Our scheme is based on mapping the objects to a dual space, where queries about moving objects are transformed into polyhedral queries concerning their speeds and initial locations. We then present a simple method for answering such polyhedral queries, based on partitioning the space into disjoint regions and using a B+-tree to index the points in each region. By appropriately selecting the boundaries of each region, we guarantee an average search time that matches a known lower bound for the problem. Specifically, for a fixed d, if the coordinates of a given set of N points are statistically independent, the proposed technique answers polyhedral queries, on the average, in O((N/B)1驴1/d驴(log B N)1/d+K/B) I/O's using O(N/B) space, where B is the block size, and K is the number of reported points. Our approach is novel in that, while it provides a theoretical upper bound on the average query time, it avoids the use of complicated data structures, making it an effective candidate for practical applications. The proposed index is also dynamic in the sense that it allows object insertion and deletion in an amortized update cost of log B(N) I/O's. Experimental results are presented to show the superiority of the proposed index over other methods based on R-trees.