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Maintenance of K-nn and spatial join queries on continuously moving points

Glenn S. Iwerks, Hanan Samet, Kenneth P. Smith
2006 ACM Transactions on Database Systems  
We present efficient algorithms to maintain k-nearest neighbor, and spatial join queries in this domain as time advances and updates occur.  ...  For example, a moving point can be represented by the function where − → x 0 is the start location, t 0 is the start time, and − → v is its velocity vector.  ...  Our main contributions in this article are query maintenance algorithms for k-nn and spatial join queries on continuously moving points that support updates to the base relations.  ... 
doi:10.1145/1138394.1138396 fatcat:cxylag4csva5znezmjyy6kk56u

Maintenance of Spatial Semijoin Queries on Moving Points [chapter]

G IWERKS, H SAMET, K SMITH
2004 Proceedings 2004 VLDB Conference  
In this paper, we address the maintenance of spatial semijoin queries over continuously moving points, where points are modeled as linear functions of time.  ...  This is analogous to the maintenance of a materialized view except, as time advances, the query result may change independently of updates.  ...  None know how the object will move ahead of time. In this paper, we address the maintenance of spatial semijoin queries over continuously moving points.  ... 
doi:10.1016/b978-012088469-8/50073-5 fatcat:dma5hz2bgfhzti6u5u7ixcqdxu

Maintenance of Spatial Semijoin Queries on Moving Points [chapter]

Glenn S. Iwerks, Hanan Samet, Kenneth P. Smith
2004 Proceedings 2004 VLDB Conference  
In this paper, we address the maintenance of spatial semijoin queries over continuously moving points, where points are modeled as linear functions of time.  ...  This is analogous to the maintenance of a materialized view except, as time advances, the query result may change independently of updates.  ...  None know how the object will move ahead of time. In this paper, we address the maintenance of spatial semijoin queries over continuously moving points.  ... 
doi:10.1016/b978-012088469-8.50073-5 dblp:conf/vldb/IwerksSS04 fatcat:6co5ngi5hveuzfn6prjbee4snu

Semantics of Spatially-Aware Windows Over Streaming Moving Objects

Kostas Patroumpas, Timos Sellis
2007 2007 International Conference on Mobile Data Management  
Several window constructs are usually specified in continuous queries over data streams as a means of limiting the amount of data processed each time and thus providing real-time responses.  ...  We systematically examine the particular case of spatiotemporal streams generated from moving point objects and we introduce a comprehensive classification of window variants useful in expressing the most  ...  We see a research challenge in continuous maintenance of such window states with respect to moving circles. Query Q3 .  ... 
doi:10.1109/mdm.2007.17 dblp:conf/mdm/PatroumpasS07 fatcat:ub74aatkezcvxlka5iageleqmm

Trajectory Clustering and k-NN for Robust Privacy Preserving k-NN Query Processing in GeoSpark

Elias Dritsas, Andreas Kanavos, Maria Trigka, Gerasimos Vonitsanos, Spyros Sioutas, Athanasios Tsakalidis
2020 Algorithms  
Th next step is to gain deeper understanding of the data through the application of k nearest neighbor (k-NN) queries either using indexing methods or otherwise.  ...  More to the point, the focus here is on the time cost of k-anonymity set computation along with vulnerability measurement.  ...  Acknowledgments: The authors gratefully acknowledge the helpful comments and suggestions of the reviewers, which have improved both content and presentation.  ... 
doi:10.3390/a13080182 fatcat:cqqosen2fjc67ebizgmci4nsrq

Continuous Monitoring of Spatial Queries [chapter]

Kenneth A. Ross, Christian S. Jensen, Richard Snodgrass, Curtis E. Dyreson, Christian S. Jensen, Richard Snodgrass, Spiros Skiadopoulos, Cristina Sirangelo, Mary Lynette Larsgaard, Gösta Grahne, Daniel Kifer, Hans-Arno Jacobsen (+106 others)
2009 Encyclopedia of Database Systems  
As cabs and pedestrians move, each free taxi driver wishes to know his/her closest client. This is an instance of continuous NN monitoring.  ...  The query points and the data objects move frequently and arbitrarily, i.e., their velocity vectors and motion patterns are unknown.  ...  Similar techniques and geometric concepts to the ones presented above also apply to problems of a non-spatial nature, such as continuous skyline [14] and top-k queries [8] .  ... 
doi:10.1007/978-0-387-39940-9_82 fatcat:473vmzuklraozbdbyammvrxp5i

Conceptual partitioning

Kyriakos Mouratidis, Dimitris Papadias, Marios Hadjieleftheriou
2005 Proceedings of the 2005 ACM SIGMOD international conference on Management of data - SIGMOD '05  
Given a set of objects P and a query point q, a k nearest neighbor (k-NN) query retrieves the k objects in P that lie closest to q.  ...  The rest of the paper is organized as follows. Section 2 surveys related work on continuous monitoring of spatial queries, focusing mostly on NN search.  ...  INTRODUCTION Early work in spatial databases focused on the point k-NN query that retrieves the k (≥1) objects from a static dataset that are closest (according to Euclidean distance) to a static query  ... 
doi:10.1145/1066157.1066230 dblp:conf/sigmod/PapadiasMH05 fatcat:b6isrhbkprh4tejmzxbpjiflhm

Continuous Nearest Neighbor Queries over Sliding Windows

Kyriakos Mouratidis, Dimitris Papadias
2007 IEEE Transactions on Knowledge and Data Engineering  
This paper studies continuous monitoring of nearest neighbor (NN) queries over sliding window streams.  ...  The task of the query processor is to constantly maintain the result of long running NN queries among the valid data.  ...  In SINA [MXA04] , the server continuously updates the reported results by performing a spatial join between moving objects and queries in three phases: (i) the hashing phase receives information about  ... 
doi:10.1109/tkde.2007.190617 fatcat:62ckdf2d5fhcdp3niyen555smu

Nearest Neighbor Search on Moving Object Trajectories [chapter]

Elias Frentzos, Kostas Gratsias, Nikos Pelekis, Yannis Theodoridis
2005 Lecture Notes in Computer Science  
The literature on NN query processing algorithms so far deals with either stationary or moving query points over static datasets or future (predicted) locations over a set of continuously moving points  ...  The proposed branch-and-bound algorithms vary with respect to the type of the query object (stationary or moving point) as well as the type of the query result (continuous or not), thus resulting in four  ...  Acknowledgements Research partially supported by the Archimedes and Pythagoras EPEAEK II Programmes of the Greek Ministry of National Education and Religious Affairs.  ... 
doi:10.1007/11535331_19 fatcat:6jy5iwygh5csbgzfyif6hc5ana

Spatial Queries in the Presence of Obstacles [chapter]

Jun Zhang, Dimitris Papadias, Kyriakos Mouratidis, Manli Zhu
2004 Lecture Notes in Computer Science  
In this paper, we study spatial queries in the presence of obstacles, where the obstructed distance between two points is defined as the length of the shortest path that connects them without crossing  ...  Despite the existence of obstacles in many database applications, traditional spatial query processing utilizes the Euclidean distance metric assuming that points in space are directly reachable.  ...  The concept of filter and refinement steps applies to all spatial queries on non-point objects.  ... 
doi:10.1007/978-3-540-24741-8_22 fatcat:fw53ai3dgzexnnsgrnj3zjtt4a

On continuously monitoring the top-k moving objects with relational group and score functions

Jian Wen, Vassilis J. Tsotras, Donghui Zhang
2009 SIGSPATIAL Special  
This paper shows a novel continuous locationbased query, called continuous relational top-k query or CRTQ, which continuously monitors the k moving objects with the most significant relations with the  ...  Although this kind of query can be implemented as a special case of the top-k join query using SQL, this straight-forward way is too expensive to be applicable widely.  ...  For example, this property holds on a k-NN group function like FG(r0, r) = {r is one of the k-NN of r0.} • The score function is monotone increasing on each object in the group.  ... 
doi:10.1145/1645424.1645426 fatcat:jgs5dqihefdfzi2ujfhktvnfxi

Algorithms for Nearest Neighbor Search on Moving Object Trajectories

Elias Frentzos, Kostas Gratsias, Nikos Pelekis, Yannis Theodoridis
2007 Geoinformatica  
The literature on NN query processing algorithms so far deals with either stationary or moving query points over static datasets or future (predicted) locations over a set of continuously moving points  ...  The proposed (depth-first and best-first) algorithms vary with respect to the type of the query object (stationary or moving point) as well as the type of the query result (historical continuous or not  ...  Research grants by the Archimedes and Pythagoras EPEAEK II Programmes jointly funded by the European Community and the Greek Ministry of National Education and Religious Affairs are also acknowledged.  ... 
doi:10.1007/s10707-006-0007-7 fatcat:gpwumvhwifhkldm235ygmxxzve

Query processing in spatial databases containing obstacles

Jun Zhang, Dimitris Papadias, Kyriakos Mouratidis, Zhu Manli
2005 International Journal of Geographical Information Science  
Despite the existence of obstacles in many database applications, traditional spatial query processing assumes that points in space are directly reachable and utilizes the Euclidean distance metric.  ...  In this paper, we study spatial queries in the presence of obstacles, where the obstructed distance between two points is defined as the length of the shortest path that connects them without crossing  ...  Acknowledgements This research was supported by the grant HKUST 6178/04E from Hong Kong RGC and the grant RGg/05 form NTU URC/AcRF.  ... 
doi:10.1080/13658810500286935 fatcat:f5g74lqz2zcshnvvvhaeqwac5i

Continuous Spatial Query Processing

Jianzhong Qi, Rui Zhang, Christian S. Jensen, Kotagiri Ramamohanarao, Jiayuan HE
2018 ACM Computing Surveys  
Continuous spatial queries require updates to the query result as the query or data objects are moving.  ...  We describe how safe regions are computed for different types of continuous spatial queries, showing how they improve query efficiency.  ...  such as the continuous spatial join query Ward et al. 2014] , which can be seen as a group of CR queries.  ... 
doi:10.1145/3193835 fatcat:427g7ca7ifahble5s3h23ald6m

BerlinMOD: a benchmark for moving object databases

Christian Düntgen, Thomas Behr, Ralf Hartmut Güting
2009 The VLDB journal  
This document presents a method to design scalable and representative moving object data (MOD) and two sets of queries for benchmarking spatio-temporal DBMS.  ...  Moreover, the BerlinMOD benchmark allows one to compare different representations of the same moving objects.  ...  We also thank the anonymous referees for their careful reviews and detailed suggestions, that have helped us to significantly improve the paper.  ... 
doi:10.1007/s00778-009-0142-5 fatcat:bfuyd2cetfgi5m2r6pzmluimxe
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