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Indexed by:期刊论文

Date of Publication:2012-06-26

Journal:KSII TRANSACTIONS ON INTERNET AND INFORMATION SYSTEMS

Included Journals:SCIE、EI、Scopus

Volume:6

Issue:6

Page Number:1546-1564

ISSN No.:1976-7277

Key Words:Pattern query; wireless sensor network; piecewise linear representation

Abstract:Pattern-based query processing has not attracted much attention in wireless sensor network though its counterpart has been studied extensively in data stream. The methods used for data stream usually consume large memory and much energy. This conflicts with the fact that wireless sensor networks are heavily constrained by their hardware resources. In this paper, we use piece wise representation to represent sensor nodes' collected data to save sensor nodes' memory and to reduce the energy consumption for query. After getting data stream's and patterns' approximated line segments, we record each line's slope. We do similar matching on slope sequences. We compute the dynamic time warping distance between slope sequences. If the distance is less than user defined threshold, we say that the subsequence is similar to the pattern. We do experiments on STM32W108 processor to evaluate our strategy's performance compared with naive method. The results show that our strategy's matching precision is less than that of naive method, but our method's energy consumption is much better than that of naive approach. The strategy proposed in this paper can be used in wireless sensor network to process pattern-based queries.