Sharing and exploring sensor streams over geocentric interfaces
Proceedings of the 16th ACM SIGSPATIAL international conference on Advances in geographic information systems
Learning, indexing, and diagnosing network faults
Proceedings of the 15th ACM SIGKDD international conference on Knowledge discovery and data mining
SEUS '09 Proceedings of the 7th IFIP WG 10.2 International Workshop on Software Technologies for Embedded and Ubiquitous Systems
Distributed velocity-dependent protocol for multihop cellular sensor networks
EURASIP Journal on Wireless Communications and Networking
Efficient spatio-temporal sensor data loading for a sensor web browser
SSTD'11 Proceedings of the 12th international conference on Advances in spatial and temporal databases
ICA3PP'12 Proceedings of the 12th international conference on Algorithms and Architectures for Parallel Processing - Volume Part II
| Hi-index | 0.00 |
We present COLR-Tree, an abstraction layer designed to support efficient spatio-temporal queries on live data gathered from a large collection of sensors. We use COLR-Tree in a publicly-available sensor web portal to separate the concerns of sensor data management from the web portal application. COLR-Tree uses two techniques to optimize end-to-end latencies of users' queries by minimizing expensive data collection from sensors. First, it uses a novel technique to effectively cache aggregate results computed over sensor data with different expiry times. Second, it incorporates an efficient one-pass sampling algorithm with its range lookup to utilize cached data and compensate for occasional unavailability of sensors. We evaluate our implementation of COLR-Tree on SQL Server 2005 with a real, large workload from Windows Live Local. Our experiments demonstrate that COLR-Tree significantly improves both the end-to-end query performance and the number of sensors accessed compared to existing techniques.