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Continuous Spatiotemporal Trajectory Joins [chapter]

Petko Bakalov, Vassilis J. Tsotras
2008 Lecture Notes in Computer Science  
Given a stream of spatiotemporal trajectories created by monitored moving objects, the outcome of a Continuous Spatiotemporal Trajectory Join (CSTJ) query is the set of objects in the stream, which have  ...  Given the plethora of GPS and location-based services, que-ries over trajectories have recently received much attention. In this paper we examine trajectory joins over streaming spatiotemporal data.  ...  Continuous Spatiotemporal Trajectory Join Given two sets of moving objects o r and o s , a spatial threshold and a (relative) time period δt (δt ∈ N), the CSTJ returns continuously the set of pairs o ri  ... 
doi:10.1007/978-3-540-79996-2_7 fatcat:duzwfghkrvcc3ea3pob3qdcure

Parallel Trajectory-to-Location Join

Shuo Shang, Lisi Chen, Kai Zheng, Christian S. Jensen, Zhewei Wei, Panos Kalnis
2018 IEEE Transactions on Knowledge and Data Engineering  
The matching between trajectories and locations, called Trajectory-to-Location join (TL-Join), is fundamental functionality in spatiotemporal data management.  ...  Given a set of trajectories, a set of locations, and a threshold θ, the TL-Join finds all (trajectory, location) pairs from the two sets with spatiotemporal correlation above θ.  ...  In contrast, the TS-Join [16] defines trajectory similarity in a continuous manner.  ... 
doi:10.1109/tkde.2018.2854705 fatcat:shvkq3mr2nethimzowyv2eiejq

Ten Benchmark Database Queries for Location-based Services

Y. Theodoridis
2003 Computer journal  
The list includes selection queries on stationary and moving reference objects, join queries and unary operations on trajectories of moving objects.  ...  Location-based services (l-services for short) compose an emerging application involving spatiotemporal databases.  ...  Of course, we admitted that more research is needed in topics, such as the spatiotemporal join processing and the processing of the so-called most similar trajectories (MST) and most similar pairs of trajectories  ... 
doi:10.1093/comjnl/46.6.713 fatcat:bpt7i5rkcfdf7lkpkppi2m7rn4

Mining Massive-Scale Spatiotemporal Trajectories in Parallel: A Survey [chapter]

Pengtao Huang, Bo Yuan
2015 Lecture Notes in Computer Science  
This survey covers essential topics including trajectory indexing and query, clustering, join, classification, pattern mining and applications.  ...  With the popularization of positioning devices such as GPS navigators and smart phones, large volumes of spatiotemporal trajectory data have been produced at unprecedented speed.  ...  data continuously.  ... 
doi:10.1007/978-3-319-25660-3_4 fatcat:qdkslwlgjzesdfnzvkbrpsgmti

Trajectory similarity join in spatial networks

Shuo Shang, Lisi Chen, Zhewei Wei, Christian S. Jensen, Kai Zheng, Panos Kalnis
2017 Proceedings of the VLDB Endowment  
We consider the case of trajectory similarity join (TS-Join), where the objects are trajectories of vehicles moving in road networks.  ...  Thus, given two sets of trajectories and a threshold θ, the TS-Join returns all pairs of trajectories from the two sets with similarity above θ.  ...  In contrast, the TS-Join uses spatiotemporal similarity, taking into account both spatial and temporal proximities in a continuous manner.  ... 
doi:10.14778/3137628.3137630 fatcat:4sfmtabdkzc6xa3w4nnst6tvi4

Time relaxed spatiotemporal trajectory joins

Petko Bakalov, Marios Hadjieleftheriou, Vassilis J. Tsotras
2005 Proceedings of the 2005 international workshop on Geographic information systems - GIS '05  
We present an experimental study revealing the advantages of using these approaches for solving Time Relaxed Spatiotemporal Trajectory Join queries.  ...  Many spatiotemporal applications store moving object data in the form of trajectories.  ...  Traditional R-tree joins [4, 10, 15] are based on intersections between MBRs while spatiotemporal trajectory join conditions are more complex.  ... 
doi:10.1145/1097064.1097091 dblp:conf/gis/BakalovHT05 fatcat:bgzjbr6j7ngqvhrs3yqivfpctu

Parallel trajectory similarity joins in spatial networks

Shuo Shang, Lisi Chen, Zhewei Wei, Christian S. Jensen, Kai Zheng, Panos Kalnis
2018 The VLDB journal  
The algorithms for the two joins exploit different upper and lower bounds on the spatiotemporal trajectory similarity and different heuristic scheduling strategies for search space pruning.  ...  We consider two cases of trajectory similarity joins (TS-Joins), including a threshold-based join (Tb-TS-Join) and a top-k TS-Join (k-TS-Join), where the objects are trajectories of vehicles moving in  ...  For each trajectory τ in P , we retrieve the trajectories spatiotemporally close to τ .  ... 
doi:10.1007/s00778-018-0502-0 fatcat:kyhx22zr6bbhphu4tsbdy2mexa

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  ...  Next, we introduce the novel idea of continuous joins between streaming trajectories, which effectively reduce to a series of snapshot trajectory joins.  ... 
doi:10.1109/mdm.2007.17 dblp:conf/mdm/PatroumpasS07 fatcat:ub74aatkezcvxlka5iageleqmm

Complex motion pattern queries for trajectories

Marcos R. Vieira, Vassilis J. Tsotras
2011 2011 IEEE 27th International Conference on Data Engineering Workshops  
In particular, we describe in detail two types of motion pattern queries: the flexible pattern queries, which focus on trajectories that follow a sequence of spatiotemporal events; and the densitybased  ...  While most previous work on trajectory-based queries has concentrated on traditional range, nearest-neighbor and similarity queries, there is still the need to query trajectories using complex, yet more  ...  Consider, for example, finding groups of trajectories that move "together", i.e. within a predefined distance to each other, for a certain continuous period of time.  ... 
doi:10.1109/icdew.2011.5767665 dblp:conf/icde/VieiraT11 fatcat:nmcglzjz3re5tpscmukay2tiom

Multi-scale Windowing over Trajectory Streams [chapter]

Kostas Patroumpas
2012 Lecture Notes in Computer Science  
properties • Not only restricting scope on recent features • But also progressively dropping redundant details  Opportunities for efficient shared evaluation  Useful in expressing spatiotemporal continuous  ...  of motion • non-overlapping paths joined at articulations -Coordinated maintenance of multiple paths • Preserve certain articulation points per trajectory  Pick samples temporally close to frame  ... 
doi:10.1007/978-3-642-33999-8_35 fatcat:4sncwdwk4bhmbofvwz4mebf3ka

Discovering spatiotemporal event sequences

Berkay Aydin, Rafal Angryk
2016 Proceedings of the 5th ACM SIGSPATIAL International Workshop on Mobile Geographic Information Systems - MobiGIS '16  
Spatiotemporal event sequences are the series of event types whose trajectory-based instances follow each other in spatiotemporal context.  ...  We introduce new data models for storing and processing evolving region trajectories, provide a novel framework for modeling spatiotemporal follow relationships, and present novel spatiotemporal event  ...  We interpolate the solar event data to create more accurate spatiotemporal trajectories of solar events, which is in the form of spatiotemporal trajectories of continuously evolving polygons.  ... 
doi:10.1145/3004725.3004735 fatcat:3m7tehj3yjawdg2htdvuwn6guu

Efficient Suspected Infected Crowds Detection Based on Spatio-Temporal Trajectories [article]

Huajun He, Ruiyuan Li, Rubin Wang, Jie Bao, Yu Zheng, Tianrui Li
2020 arXiv   pre-print
Existing metrics can not correctly address the infected rate on trajectories.  ...  To solve this problem, we propose a novel spatio-temporal infected rate (IR) measure based on human moving trajectories that can adequately describe the risk of being infected by a given query trajectory  ...  JOIN SOLUTION Basic Idea To process plenty of trajectories infected rates, we develop a join query solution, named Infected Rate Join Query (IRJQ).  ... 
arXiv:2004.06653v1 fatcat:nebzqpp635hwpf5fe26x4nfb6q

Discovery of Collocation Episodes in Spatiotemporal Data

Huiping Cao, Nikos Mamoulis, David Cheung
2006 IEEE International Conference on Data Mining. Proceedings  
Given a collection of trajectories of moving objects with different types (e.g., pumas, deers, vultures, etc.), we introduce the problem of discovering collocation episodes in them (e.g., if a puma is  ...  Spatiotemporal sequences and close subsequences A spatiotemporal sequence S is the trajectory of a moving object.  ...  Introduction The large volume of the spatiotemporal data, (i.e., moving objects trajectories) renders their manual analysis tedious and impossible.  ... 
doi:10.1109/icdm.2006.59 dblp:conf/icdm/CaoMC06 fatcat:lbjyfmua2verriemanzonxc5w4

T-DBSCAN: A Spatiotemporal Density Clustering for GPS Trajectory Segmentation

Wen Chen, Minhe Ji, Jianmei Wang
2014 International Journal of Online Engineering (iJOE)  
Two new premises (i.e. state continuity within a single stop and temporal disjuncture among stops) were proposed as a theoretical basis for regulating the trajectory point selection in clustering.  ...  of the trajectories.  ...  It first creates clus-PAPER T-DBSCAN: A SPATIOTEMPORAL DENSITY CLUSTERING FOR GPS TRAJECTORY SEGMENTATION ters by searching the continuous density-based neighborhood of qualified core points, then expands  ... 
doi:10.3991/ijoe.v10i6.3881 fatcat:22agm7yzmrcprcemajlgk73ixi

SaIL: A Spatial Index Library for Efficient Application Integration

Marios Hadjieleftheriou, Erik Hoel, Vassilis J. Tsotras
2005 Geoinformatica  
Work Experience Working for the database research group. 1 . 1 Time Relaxed Spatiotemporal Trajectory Join, Conference Publications P. Bakalov, M. Hadjieleftheriou, V. J.  ...  Efficient Indexing of Spatiotemporal Objects, M. Hadjieleftheriou, G. Kollios, V. J. Tsotras, D.  ... 
doi:10.1007/s10707-005-4577-6 fatcat:pbfxbdec35eezdyk7gmmah2ldi
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