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Straight-Path Queries in Trajectory Data [chapter]

Mark de Berg, Ali D. Mehrabi
2015 Lecture Notes in Computer Science  
s and t, report all sub-trajectories in which the player moved in a more or less straight line from s to t.  ...  Inspired by sports analysis, we study data structures for storing a trajectory representing the movement of a player during a game, such that the following queries can be answered: Given two positions  ...  We thus need a data structure storing a collection of trajectories (corresponding to the movements of player X in all matches) such that we can efficiently answer straight-path queries: given a directed  ... 
doi:10.1007/978-3-319-15612-5_10 fatcat:wwduz2ui7rg5fh4gdonabvoyuu

Straight-path queries in trajectory data

Mark de Berg, Ali D. Mehrabi
2016 Journal of Discrete Algorithms  
s and t, report all sub-trajectories in which the player moved in a more or less straight line from s to t.  ...  Inspired by sports analysis, we study data structures for storing a trajectory representing the movement of a player during a game, such that the following queries can be answered: Given two positions  ...  We thus need a data structure storing a collection of trajectories (corresponding to the movements of player X in all matches) such that we can efficiently answer straight-path queries: given a directed  ... 
doi:10.1016/j.jda.2015.08.002 fatcat:2pkzgu6txbeytgekczgidoeroq

Semantic trajectory compression: Representing urban movement in a nutshell

Kai-Florian Richter, Falko Schmid, Patrick Laube
2012 Journal of Spatial Information Science  
data.  ...  STC allows for substantially compressing trajectory data with acceptable information loss.  ...  For description "straight" there is only one element in candidates. path ← append(path, partpath);21Set compressed ← tail(compressed); 22 end 23 return path.  ... 
doi:10.5311/josis.2012.4.62 fatcat:x5bp4aaajzg6xio6pg2quujys4

Multi-scale Windowing over Trajectory Streams [chapter]

Kostas Patroumpas
2012 Lecture Notes in Computer Science  
(CQ)  overcome lack of suitable operators in traditional DBMS  Towards a new processing paradigm: GeoStreaming -query evaluation -in-memory indexing -data reduction/approximation • PAST  maintain historical  ...  -Approximate according to motion pattern & reporting frequency • e.g., discard superfluous points when moving along a straight path at constant speed • Smaller scale  more approximation • Trajectory-filtered  ... 
doi:10.1007/978-3-642-33999-8_35 fatcat:4sncwdwk4bhmbofvwz4mebf3ka

Automatic multi-trajectory planning solution for steerable catheters

Alberto Favaro, Leonardo Cerri, Davide Scorza, Elena De Momi
2018 2018 International Symposium on Medical Robotics (ISMR)  
The present work describes a novel approach to trajectory planning for minimally invasive surgery consisting of an algorithm able to provide the surgeon with multiple curvilinear paths to connect an entry  ...  The case of study of the work consists of a typical Deep Brain Stimulation scenario where tests have been performed in order to compare the result obtained from standard rectilinear trajectory planning  ...  single-query planning task and performs a path optimization in order to meet PBN constraints.  ... 
doi:10.1109/ismr.2018.8333284 dblp:conf/ismr/FavaroCSM18 fatcat:rilpci7iyre4dj6vmqb6iz3p6u

PNN query processing on compressed trajectories

Shuo Shang, Bo Yuan, Ke Deng, Kexin Xie, Kai Zheng, Xiaofang Zhou
2011 Geoinformatica  
In this paper, we investigate a novel problem of searching the Path Nearest Neighbor based on Compressed Trajectories (PNN-CT query).  ...  The efficiency of the proposed PNN-CT query processing is verified by extensive experiments based on real and synthetic trajectory data in road networks.  ...  Introduction Path Nearest Neighbor (PNN) Query [8, 26, 36] is a well defined problem in spatial databases, which is designed to find the closest data object to the specified path.  ... 
doi:10.1007/s10707-011-0144-5 fatcat:apfahzkizvc3tgmo7mv7ngpufa

Nonmaterialized Motion Information in Transport Networks [chapter]

Hu Cao, Ouri Wolfson
2004 Lecture Notes in Computer Science  
The traditional way of representing motion in 3D space-time uses a trajectory, i.e. a sequence of (x,y,t) points.  ...  Such a trajectory may be produced by periodic sampling of a Global Positioning System (GPS) receiver. The are two problems with this representation of motion. First, imprecision due to errors (e.g.  ...  When giving driving directions, one could indicate: starting from (x 1 , y 1 ) drive in a straight line to (x 2 , y 2 ), from there drive in a straight line to (x 3 , y 3 ), etc.  ... 
doi:10.1007/978-3-540-30570-5_12 fatcat:2vgpe445yraq5jfh7uynaod5sa

A Spatiotemporal Model and Language for Moving Objects on Road Networks [chapter]

Michalis Vazirgiannis, Ouri Wolfson
2001 Lecture Notes in Computer Science  
In this paper we define a concise data model and a set of powerful query predicates for moving objects.  ...  Moving object databases are becoming more popular due to the increasing number of application domains that deal with moving entities and need to pose queries.  ...  The data types have been defined in the previous section. Here we will define the query predicates in terms of SQL extensions.  ... 
doi:10.1007/3-540-47724-1_2 fatcat:waaaxvmtkvfajpaynu7c5h2s7m

PiLoc: A self-calibrating participatory indoor localization system

Chengwen Luo, Hande Hong, Mun Choon Chan
2014 IPSN-14 Proceedings of the 13th International Symposium on Information Processing in Sensor Networks  
In this work, we propose PiLoc, an indoor localization system that utilizes opportunistically sensed data contributed by users.  ...  The key novelty of PiLoc is that it merges walking segments annotated with displacement and signal strength information from users to derive a map of walking paths annotated with radio signal strengths  ...  While path segment can take any form in general, in this work, we consider only two kinds of path segments, namely: turns and long straight lines.  ... 
doi:10.1109/ipsn.2014.6846748 fatcat:vfex2go72za53ly7q5d4s2teue

Building Agent-Based Walking Models by Machine-Learning on Diverse Databases of Space-Time Trajectory Samples

Paul Torrens, Xun Li, William A. Griffin
2011 Transactions on GIS  
agent-based models with hypotheses that are informed or translated from data, and the construction of algorithms for extracting and annotating space-time paths in massive data-sets.  ...  in simulation from simple trajectory samples.  ...  Acknowledgements This material is based in part upon work supported by the National Science Foundation under grant numbers 1002517, 0643322, and 0624208.  ... 
doi:10.1111/j.1467-9671.2011.01261.x fatcat:wrb7nto4ovfbvilybvfaexxufi

Supporting Pattern-Matching Queries over Trajectories on Road Networks

Gook-Pil Roh, Jong-Won Roh, Seung-Won hwang, Byoung-Kee Yi
2011 IEEE Transactions on Knowledge and Data Engineering  
In contrast, we first identify some desirable properties for pattern matching queries to the road network trajectories.  ...  This paper studies pattern matching problems for trajectory data over road networks, which complements existing efforts focusing on (a) a spatio-temporal window query for location-based service or (b)  ...  Querying over the paths of such objects, or trajectories, has thus gained attention lately.  ... 
doi:10.1109/tkde.2010.189 fatcat:wq2nkundufcmrnhljpcfyggr5e

Mining Trajectories for Spatio-temporal Analytics

Songhua Xing, Xuan Liu, Qing He, Arun Hampapur
2012 2012 IEEE 12th International Conference on Data Mining Workshops  
In this paper, we introduce a trajectory mining system to generate the trajectory heat map at aggregated level for the online spatial-temporal analytics.  ...  The proposed method is effective and fast since we only focus on a small set of trajectory points, which capture all trajectory patterns.  ...  On the other hand, as all the sub-trajectories are the exact shortest paths, we can reconstruct them very fast by using A* algorithm or store them with high efficient data structure (such as path oracles  ... 
doi:10.1109/icdmw.2012.25 dblp:conf/icdm/XingLHH12 fatcat:joliaxv3ifaufp4fscevmo4gle

Tracking Mobile Sinks via Analysis of Movement Angle Changes in WSNs

Guisong Yang, Huifen Xu, Xingyu He, Gang Wang, Naixue Xiong, Chunxue Wu
2016 Sensors  
The simulation results consolidate that DAMST has advantages in reducing energy consumption and data overhead.  ...  If it needs information from the region agent in a future time it will construct an energy efficient path from the region agent to itself by calculating its own movement angles according to the footprints  ...  Acknowledgments: The authors would like to appreciate all anonymous reviewers for their insightful comments and constructive suggestions to polish this paper in high quality.  ... 
doi:10.3390/s16040449 pmid:27043562 pmcid:PMC4850963 fatcat:srkwakhlvzgmpomnryhsludxh4

Retrieving Similar Trajectories from Cellular Data at City Scale [article]

Zhihao Shen, Wan Du, Xi Zhao, Jianhua Zou
2019 arXiv   pre-print
Unlike previous works based on fine-grained GPS trajectories, this paper investigates the feasibility of identifying similar trajectories from cellular data observed by mobile infrastructure, which provide  ...  To handle the large localization errors and low sample rates of cellular data, we develop a holistic system, cellSim, which seamlessly integrates map matching and similar trajectory search.  ...  For all M trajectories, some sub-paths are the same, e.g., some parts with straight road segments.  ... 
arXiv:1907.12371v2 fatcat:gpyuv6zjdfgazed3mazlypfowm

PRM-RL: Long-range Robotic Navigation Tasks by Combining Reinforcement Learning and Sampling-based Planning [article]

Aleksandra Faust, Oscar Ramirez, Marek Fiser, Kenneth Oslund, Anthony Francis, James Davidson, Lydia Tapia
2018 arXiv   pre-print
In the indoor navigation task, PRM-RL successfully completes up to 215 m long trajectories under noisy sensor conditions, and the aerial cargo delivery completes flights over 1000 m without violating the  ...  We present PRM-RL, a hierarchical method for long-range navigation task completion that combines sampling based path planning with reinforcement learning (RL).  ...  The data points' x and y coordinates are the queries' goal location in the city projected onto xy-plane.  ... 
arXiv:1710.03937v2 fatcat:3xsox7uy5nfvvkwuuhlmn2t2hq
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