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Forward node-selecting queries over trees

Dan Olteanu
2007 ACM Transactions on Database Systems  
Node-selecting queries over trees lie at the core of several important XML languages for the Web, e.g., the node-selection language XPath, the query language XQuery and the transformation language XSLT  ...  This work is devoted to an expressiveness study of node-selecting queries with proven theoretical and practical applicability, especially in the field of query evaluation against XML streams.  ...  XPath is the prime language for expressing node-selecting queries on trees.  ... 
doi:10.1145/1206049.1206052 fatcat:qqruq5qqvzc5rdgbgn7ry5ahyu

Spatial queries in sensor networks

Amir Soheili, Vana Kalogeraki, Dimitrios Gunopulos
2005 Proceedings of the 2005 international workshop on Geographic information systems - GIS '05  
We develop a distributed spatial index over the sensor nodes that is used in processing spatial queries in a distributed fashion.  ...  We evaluate the behavior of our approach and show that our mechanism provides an efficient and scalable way to run spatial queries over sparse and dense sensor networks.  ...  Non-leaf nodes store an MBR that covers all the MBRs in the children nodes. Variants of the R-Tree structure such as R+Tree [17] and R*Tree [16] have also been proposed.  ... 
doi:10.1145/1097064.1097074 dblp:conf/gis/SoheiliKG05 fatcat:dmly4gvjejb6jdiaquoftctrm4

D-ODMRP: a destination-driven on-demand multicast routing protocol for mobile ad hoc networks

Y. Yan, K. Tian, K. Huang, B. Zhang, J. Zheng
2012 IET Communications  
Simulation results show that D-ODMRP can significantly improve the forwarding efficiency as compared with ODMRP.  ...  This article proposes a destination-driven on-demand multicast routing protocol (D-ODMRP) to improve the multicast forwarding efficiency in mobile ad hoc networks (MANETs).  ...  The basic idea behind DDMC is to give the low-cost path passing through a multicast destination node priority over other paths in order to add a new node to the current tree in a tree construction process  ... 
doi:10.1049/iet-com.2011.0033 fatcat:n5c6l6663nfe3abmoch2oljywi

Routing and processing multiple aggregate queries in sensor networks

Niki Trigoni, Alexandre Guitton, Antonios Skordylis
2006 Proceedings of the 4th international conference on Embedded networked sensor systems - SenSys '06  
Tree construction is currently performed using simple flooding algorithms, data-centric reinforcement strategies or energy-aware route selection schemes.  ...  Given a query workload and a special-purpose gateway node where results are expected, the query optimizer exploits query correlations in order to generate an energyefficient distributed evaluation plan  ...  After a tree is constructed, sensor nodes forward their readings along the paths of the tree, evaluating partial query results at intermediate nodes.  ... 
doi:10.1145/1182807.1182871 dblp:conf/sensys/TrigoniGS06 fatcat:kbjnss3w7zdvxbqlqsbkbwbuju

Joint Sensor Selection And Routing For Distributed Estimation In Wireless Sensor Networks

Baltasar Beferull-Lozano, Eduardo Portu-Repollés
2009 Zenodo  
Therefore, for each given sensor, the optimal way to send its measurement to the querying node is to do it over the shortest path tree.  ...  piece is forwarded to the next node in the tree.  ... 
doi:10.5281/zenodo.41507 fatcat:qw5iljgtvzaw3c3ejwavzkdgci

A Decentralized Storage Scheme for Multi-Dimensional Range Queries over Sensor Networks

Lei Xie, Lijun Chen, Daoxu Chen, Li Xie
2009 2009 15th International Conference on Parallel and Distributed Systems  
This paper presents the design of a decentralized storage scheme to support multi-dimensional range queries over sensor networks.  ...  We build a distributed k-d tree based index structure over sensor network, so as to efficiently map high dimensional event data to a two-dimensional space of sensors while preserving the proximity of events  ...  The first strategy is to route sub-queries separately to corresponding zones by selecting nearest storage nodes for the query node.  ... 
doi:10.1109/icpads.2009.24 dblp:conf/icpads/Xie0CX09 fatcat:a52dglvlr5ehjiub4x6svqmcdi

A substrate for in-network sensor data integration

Svilen R. Mihaylov, Marie Jacob, Zachary G. Ives, Sudipto Guha
2008 Proceedings of the 5th workshop on Data management for sensor networks - DMSN '08  
sets of nodes performing distributed joins in sensor networks.  ...  With the ultimate goal of extending the data integration paradigm and query processing capabilities to ad hoc wireless networks, sensors, and stream systems, we consider how to support communication between  ...  If a node has such a possibility and satisfies its selection conditions, it forwards data over the routing tree to the base station, which evaluates ψRS.  ... 
doi:10.1145/1402050.1402059 dblp:conf/dmsn/MihaylovJIG08 fatcat:lrrmgt6xzbdbpedyhzbphzp3li

Query Plan Execution in a Heterogeneous Stream Management System for Situational Awareness

Indrakshi Ray, Sanjay K. Madria, Mark Linderman
2012 2012 IEEE 31st Symposium on Reliable Distributed Systems  
We show how multiple queries can be represented in the form of an operator tree, such that their commonalities can be easily exploited for multi query plan generation.  ...  Battlefield monitoring involves collecting streaming data from different sources, transmitting the data over a heterogeneous network, and processing queries in real-time in order to respond to events in  ...  The operator tree is first forwarded to the partition that contains the maximum number of source vertices for the query.  ... 
doi:10.1109/srds.2012.54 dblp:conf/srds/RayML12 fatcat:vdopbizxi5hhtow637j2uecraa

Supporting Generic Cost Models for Wide-Area Stream Processing

Olga Papaemmanouil, Ugur Çetintemel, John Jannotti
2009 Proceedings / International Conference on Data Engineering  
Based on the desired performance goals, the system progressively refines the query deployment, the structure of the overlay trees, as well as the statistics collection process.  ...  To facilitate light-weight dynamic changes on the query deployment, XFlow relies on a loosely-coupled, flexible architecture consisting of multiple publish-subscribe overlay trees that can gracefully scale  ...  Each node forwards statistics of constant size (O(1)) for each tree is participates.  ... 
doi:10.1109/icde.2009.11 dblp:conf/icde/PapaemmanouilCJ09 fatcat:qv6xgekp2fdfrawg3nazgsyswu

Dynamic multiroot, multiquery processing based on data sharing in sensor networks

Zhiguo Zhang, Ajay D. Kshemkalyani, Sol M. Shatz
2010 ACM transactions on sensor networks  
The following is an example of such a query for monitoring harmful radiation in some building: SELECT room, AVG(radiation) FROM sensordb WHERE building = ERF GROUP BY room HAVING AVG(radiation) > 100 DURATION  ...  Energy constraints make optimizing query processing particularly important. This paper addresses multi-root, multi-query optimization for region queries.  ...  Node A first tests if it has already selected a routing-tree parent node (line 2) for this query.  ... 
doi:10.1145/1754414.1754421 fatcat:2whtssqnebdxvito5fdtrfydae

Along & across algorithm for routing events and queries in wireless sensor networks

Tat Wing Chim
2005 2005 International Symposium on Intelligent Signal Processing and Communication Systems  
Our Along & Across algorithm makes use of a hop tree structure. Event attributes are routed along hop levels while queries are routed across hop levels to seek for match.  ...  In this paper, we investigate efficient strategies for routing events and queries in a wireless sensor network where energy is a major concern.  ...  For each of the 10 random topologies, we built a hop tree rooted at a randomly selected node.  ... 
doi:10.1109/ispacs.2005.1595512 fatcat:kt2xiaxteva7loo4c52hjoov4y

Twig Pattern Matching: A Revisit [chapter]

Jiang Li, Junhu Wang, Maolin Huang
2011 Lecture Notes in Computer Science  
Twig pattern matching plays a crucial role in xml query processing.  ...  We propose two approaches, namely re-test checking and forward-to-end, which can avoid the redundant computation and can be easily applied to both holistic one-phase and two-phase algorithms.  ...  In our approach forward-to-end, we select two time points for skipping. Consider a query tree rooted at Q.  ... 
doi:10.1007/978-3-642-23091-2_4 fatcat:r73exfz57vd5pn4vc75afyuzrq

A Modified Shared-tree Multicast Routing Protocol in Ad Hoc Network

Ziping Liu, Bidyut Gupta
2005 Journal of Computing and Information Technology  
The protocol uses the n-hop local ring search to establish a new forwarding path and limit the flooding region.  ...  Shared-tree routing protocol is a widely used multicast routing protocol in ad hoc networks. However, this protocol is deficient in terms of the end-to-end delay and network throughput.  ...  Three different roaming network areas are simulated: 100 nodes over a square (2100 2100m) space, 50 nodes over a square (1500 1500m) space and 25 nodes over a square (750 750m) space.  ... 
doi:10.2498/cit.2005.03.02 fatcat:5wv6hntsqnd4jkttn3nj2nvbye

Load-balanced query dissemination in privacy-aware online communities

Emiran Curtmola, Alin Deutsch, K. K. Ramakrishnan, Divesh Srivastava
2010 Proceedings of the 2010 international conference on Management of data - SIGMOD '10  
Each QDT has data publishers as its leaf nodes, and overlay network nodes as its internal nodes; each internal node routes queries to publishers, based on a summary of the data advertised by publishers  ...  We propose a distributed index structure, UQDT, that is organized as a union of Query Dissemination Trees (QDTs), and realized on an overlay (i.e., logical) network infrastructure.  ...  We propose the organization of the internal nodes into a logical tree we call a Query Dissemination Tree (QDT). The internal QDT nodes are routers, the publishers are leaves.  ... 
doi:10.1145/1807167.1807219 dblp:conf/sigmod/CurtmolaDRS10 fatcat:tz77tfngp5d73gnkmf4mwlquhe

Moara: Flexible and Scalable Group-Based Querying System [chapter]

Steven Y. Ko, Praveen Yalagandula, Indranil Gupta, Vanish Talwar, Dejan Milojicic, Subu Iyer
2008 Lecture Notes in Computer Science  
First, Moara builds aggregation trees for different groups and adaptively maintains the trees to optimize the total message cost.  ...  Though there exist several distributed querying systems for this monitoring purpose, they are not group-based; they mostly focus on querying the entire system.  ...  These extra nodes would typically be internal tree nodes that are forwarding queries down or responses up the tree, but which do not satisfy the predicate themselves.  ... 
doi:10.1007/978-3-540-89856-6_21 fatcat:vlqqaslfufawxmh74o4huvt6iu
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