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Communication Steps for Parallel Query Processing [PDF]
, 2013 We consider the problem of computing a relational query $q$ on a large input database of size $n$, using a large number $p$ of servers. The computation is performed in rounds, and each server can receive only $O(n/p^{1-\varepsilon})$ bits of data, where $
Beame, Paul +2 more
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A Distributed Query Processing Engine [PDF]
, 2003 Wireless sensor networks (WSNs) are formed of tiny, highly energy-constrained sensor nodes that are equipped with wireless transceivers. They may be mobile and are usually deployed in large numbers in unfamiliar environments.
Chatterjea, Supriyo, Havinga, Paul
core +1 more source
Distance-Constraint k-Nearest Neighbor Searching in Mobile Sensor Networks
Sensors, 2015 The κ -Nearest Neighbors ( κNN) query is an important spatial query in mobile sensor networks. In this work we extend κNN to include a distance constraint, calling it a l-distant κ-nearest-neighbors ( l ...
Yongkoo Han +4 more
doaj +1 more source
Intelligent Collaborative Event Query Algorithm in Wireless Sensor Networks
International Journal of Distributed Sensor Networks, 2011 Event query processing is a very important issue in wireless sensor networks (WSNs). In order to detect event early and provide monitoring information and event query timely in WSNs, an efficient intelligent collaborative event query (ICEQ) algorithm is ...
Rongbo Zhu
doaj +1 more source
Sensors, 2018 With the rapid development of mobile devices and sensors, effective searching methods for big spatial data have recently received a significant amount of attention.
Bumjoon Jo, Sungwon Jung
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k Nearest Neighbor Search for Location-Dependent Sensor Data in MANETs
IEEE Access, 2015 K nearest neighbor (kNN) queries, which retrieve the k nearest sensor data items associated with a location (location-dependent sensor data) from the location of the query issuer, are useful for location-based services in mobile environments.
Yuka Komai +3 more
doaj +1 more source
Skew in parallel query processing [PDF]
Proceedings of the 33rd ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems, 2014 We study the problem of computing a conjunctive query q in parallel, using p of servers, on a large database. We consider algorithms with one round of communication, and study the complexity of the communication. We are especially interested in the case where the data is skewed, which is a major challenge for scalable parallel query processing.
Paul Beame, Paraschos Koutris, Dan Suciu
openaire +3 more sources
Efficient Group K Nearest-Neighbor Spatial Query Processing in Apache Spark
ISPRS International Journal of Geo-Information, 2021 Aiming at the problem of spatial query processing in distributed computing systems, the design and implementation of new distributed spatial query algorithms is a current challenge.
Panagiotis Moutafis +3 more
doaj +1 more source
CBSL - A Compressed Binary String Labeling Scheme for Dynamic Update of XML documents
Journal of Computing and Information Technology, 2018 The growing volume of XML documents over the Web has increased the need for an efficient mechanism to facilitate query processing. Many labeling schemes have been introduced to optimize data retrieval and query processing on XML database documents. As it
Dhanalekshmi Gopinathan, Krishna Asawa
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Enabling Secure Database as a Service using Fully Homomorphic Encryption: Challenges and Opportunities [PDF]
, 2013 The database community, at least for the last decade, has been grappling with querying encrypted data, which would enable secure database as a service solutions.
Gunda, Manikanta +2 more
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