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A Natural-language-based Visual Query Approach of Uncertain Human Trajectories

Zhaosong Huang, Ye Zhao, Wei Chen, Shengjie Gao, Kejie Yu, Weixia Xu, Mingjie Tang, Minfeng Zhu, Mingliang Xu
2019 IEEE Transactions on Visualization and Computer Graphics  
The visual interface facilitates query condition specification, situation-aware visualization, and semantic exploration of large trajectory data.  ...  It is built up on encoding massive, spatially uncertain trajectories by the semantic information of the POls and regions covered by them, and then storing the trajectory documents in text database with  ...  KNN-based queries refer to retrieving top K trajectories which have the minimum distance to given locations.  ... 
doi:10.1109/tvcg.2019.2934671 pmid:31443013 fatcat:pa7womdqdrasnl6awvhoynuuhi

A Survey on Trajectory Data Mining: Techniques and Applications

Zhenni Feng, Yanmin Zhu
2016 IEEE Access  
A trajectory is typically represented by a sequence of timestamped geographical locations. A wide spectrum of applications can benefit from the trajectory data mining.  ...  Furthermore, this paper reviews an extensive collection of existing trajectory data mining techniques and discusses them in a framework of trajectory data mining.  ...  queries, range queries, nearest neighbor queries, top-k queries, pattern queries, aggregate queries and other application-specific queries.  ... 
doi:10.1109/access.2016.2553681 fatcat:bwz3c6oyfjahroihps7i3wo76q

HERMES

Nikos Pelekis, Elias Frentzos, Nikos Giatrakos, Yannis Theodoridis
2015 International Journal of Knowledge-Based Organizations  
ABSTRACT This paper presents HERMES, a prototype DB engine that defines a powerful query language for trajectory databases, which enables the support of mobility-centric applications, such as Location-Based  ...  HERMES extends the data definition and manipulation language of Object-Relational DBMS (ORDBMS) with spatio-temporal semantics and functionality based on advanced spatio-temporal indexing and query processing  ...  Among them, an important class of queries is the so-called k nearest neighbor (k-NN) search, where one is interested in finding the k closest trajectories to a predefined query object Q (stationary or  ... 
doi:10.4018/ijkbo.2015040102 fatcat:dh3clxukbfbljdmf3gmfw6zmgi

A hybrid model towards moving route prediction under data sparsity

Liang Wang, Mei Wang, Tao Ku, Yong Cheng, Xinying Guo
2017 2017 20th International Conference on Information Fusion (Fusion)  
And the response time for each query trajectory is acceptable for most application cases.  ...  Actually, the existing sparse dataset cannot cover sufficient query routes, and then the match-based approach may return no results at all.  ...  However, the maximum response time in HMRP is 0.206 second for each query trajectory, that is sufficient for most application cases. 2) Varying the top-k parameter in Markov model: We also investigate  ... 
doi:10.23919/icif.2017.8009862 dblp:conf/fusion/WangWKCG17 fatcat:g5zqfrkjsbfcxdyefhspwm4i5y

Prediction of Suspect Location Based on Spatiotemporal Semantics

Lian Duan, Xinyue Ye, Tao Hu, Xinyan Zhu
2017 ISPRS International Journal of Geo-Information  
In the domain of LBSN (Location-based Social Networks), researchers address this issue by utilizing the trajectory data of all or relevant users to create "synthesized" trajectories or integrating heterogeneous  ...  However, it is impractical to synthesize trajectory data of all suspects since suspects might have different mobility patterns from the public.  ...  Thus, the ratio of correct times to the total times is called top-k precision.  ... 
doi:10.3390/ijgi6070185 fatcat:mxnjrljhn5avzd6lz7evis7xvu

Advanced knowledge discovery on movement data with the GeoPKDD system

M. Nanni, R. Trasarti, C. Renso, F. Giannotti, D. Pedreschi
2010 Proceedings of the 13th International Conference on Extending Database Technology - EDBT '10  
The system combines spatio-temporal querying capabilities with data mining and semantic technologies, thus providing a full support for the Mobility Knowledge Discovery process.  ...  The growing availability of mobile devices produces an enormous quantity of personal tracks which calls for advanced analysis methods capable of extracting knowledge out of massive trajectories datasets  ...  k-anonimity notion.  ... 
doi:10.1145/1739041.1739129 dblp:conf/edbt/NanniTRGP10 fatcat:tlzrrfrgefeurmac7q27shk3em

A Survey on Trajectory Data Management, Analytics, and Learning [article]

Sheng Wang, Zhifeng Bao, J. Shane Culpepper, Gao Cong
2020 arXiv   pre-print
We also explore four closely related analytical tasks commonly used with trajectory data in interactive or real-time processing. Deep trajectory learning is also reviewed for the first time.  ...  In this survey, we comprehensively review recent research trends in trajectory data management, ranging from trajectory pre-processing, storage, common trajectory analytic tools, such as querying spatial-only  ...  further build POI links based on time periods.  ... 
arXiv:2003.11547v2 fatcat:5gf5h5skqjbrhf67cflygggnky

Semantrix: A Compressed Semantic Matrix [article]

Nieves R. Brisaboa, Antonio Fariña, Gonzalo Navarro, Tirso V. Rodeiro
2020 arXiv   pre-print
answer cumulative queries.  ...  its efficiency when answering different types of queries.  ...  queries: For these queries, a FM-index built on top of H vector is used.  ... 
arXiv:2002.12050v2 fatcat:ofnmtozuubf7nkj4i5c4n7l5pa

Semantic-based Anomalous Pattern Discovery in Moving Object Trajectories [article]

Elena Camossi, Paola Villa, Luca Mazzola
2013 arXiv   pre-print
Afterwards, movement patterns have to be formalized, either as Description Logic (DL) axioms or queries, enabling the retrieval of the trajectories that follow the patterns.  ...  In this work, we investigate a novel semantic approach for pattern discovery in trajectories that, relying on ontologies, enhances object movement information with event semantics.  ...  [17] give also a ranking of the top-k significant locations for each trajectory. The significance of locations for a user is discussed also by Zheng et al.  ... 
arXiv:1305.1946v1 fatcat:ew73vsohjbh47b7egfivcachca

Releasing Differentially Private Trajectories with Optimized Data Utility

Bing Li, Hong Zhu, Meiyi Xie
2022 Applied Sciences  
However, existing works are primarily concerned with maintaining the trajectory data geographic utility and neglect the semantic utility.  ...  ., semantic annotation, suffer from poor performance.  ...  Given the actual dataset D A and its obfuscated version D O , we find out top-k periodic patterns PP(D A ) and PP(D O ) from each dataset, respectively.  ... 
doi:10.3390/app12052406 fatcat:afxhckmpfza5dd6ufojzgzizsy

Moving Objects Analytics: Survey on Future Location & Trajectory Prediction Methods [article]

Harris Georgiou, Sophia Karagiorgou, Yannis Kontoulis, Nikos Pelekis, Petros Petrou, David Scarlatti, Yannis Theodoridis
2018 arXiv   pre-print
, trajectory prediction, future location prediction.  ...  This paper focuses on predictive analytics for moving objects (could be pedestrians, cars, vessels, planes, animals, etc.) and surveys the state-of-the-art in the context of future location and trajectory  ...  The movement rules are discovered by iteratively identifying sets of frequent trajectories of length k based on frequent trajectories of length k-1.  ... 
arXiv:1807.04639v1 fatcat:lvje57kod5eldaplkl53wbwgti

Spatiotemporal Pattern Mining: Algorithms and Applications [chapter]

Zhenhui Li
2014 Frequent Pattern Mining  
We classify the patterns into three categories: (1) individual periodic pattern; (2) pairwise movement pattern and (3) aggregative patterns over multiple trajectories.  ...  This chapter states the challenges of pattern discovery, reviews the state-of-the-art methods and also discusses the limitations of existing methods.  ...  We categorize the patterns as individual periodic patterns, pairwise patterns, and aggregate patterns over multiple trajectories.  ... 
doi:10.1007/978-3-319-07821-2_12 fatcat:t6ecqptztrbntp5xtmuauqoasm

iDiary

Dan Feldman, Cynthia Sung, Andrew Sugaya, Daniela Rus
2015 ACM transactions on sensor networks  
and receive textual answers based on their GPS signals. iDiary uses novel algorithms for semantic compression (known as coresets) and trajectory clustering of massive GPS signals in parallel to compute  ...  The system features a user interface similar to Google Search that allows users to type text queries on their activities (e.g., "Where did I buy books?")  ...  Figure 4 : 4 Semantic map of a user's trajectories. Figure 5 : 5 Top: Images of Bob's trajectory and approximations in 3-D (time, latitude, longitude) space.  ... 
doi:10.1145/2814569 fatcat:2db37vjzirgtba2shnfnij6egu

iDiary

Dan Feldman, Andrew Sugaya, Cynthia Sung, Daniela Rus
2013 Proceedings of the 11th ACM Conference on Embedded Networked Sensor Systems - SenSys '13  
and receive textual answers based on their GPS signals. iDiary uses novel algorithms for semantic compression (known as coresets) and trajectory clustering of massive GPS signals in parallel to compute  ...  The system features a user interface similar to Google Search that allows users to type text queries on their activities (e.g., "Where did I buy books?")  ...  Figure 4 : 4 Semantic map of a user's trajectories. Figure 5 : 5 Top: Images of Bob's trajectory and approximations in 3-D (time, latitude, longitude) space.  ... 
doi:10.1145/2517351.2517366 dblp:conf/sensys/FeldmanSSR13 fatcat:t55wdj4tjrdt5pqwpdsmzpvz74

A Graph Based Visual Query Method for Massive Human Trajectory Data

Zhongshuai Wang, Yuan Yuan, Liang Chang, Xiyan Sun, Xiaonan Luo
2019 IEEE Access  
Query is an essential task for trajectory exploration. To do this, users should input spatial, temporal and other types of query conditionals to obtain a group of filtered trajectories.  ...  These trajectories have shown great values in supporting situation-aware exploration and prediction of human mobility, discovering movement patterns and monitoring the traffic situations.  ...  The existing trajectory analysis methods are generally clustering or semantic query for trajectory but rarely based on the trajectory query between nodes or regions.  ... 
doi:10.1109/access.2019.2948304 fatcat:li7glaitrjgyjohrfwj367e4qi
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