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Range-kNN queries with privacy protection in a mobile environment

Zhou Shao, David Taniar, Kiki Maulana Adhinugraha
2015 Pervasive and Mobile Computing  
In order to protect the privacy of users' personal information, we proposed Range-kNN queries, which uses the query range instead of one single query point.  ...  With the help of location-based services (LBS), mobile users are able to access their actual locations, which can be used to search for information around them which they are interested in.  ...  Although our algorithm proved to be efficient to handle Range-kNN queries based spatial road networks, it only focuses on the static objects.  ... 
doi:10.1016/j.pmcj.2015.05.004 fatcat:3n3rybxlljhmvmc3a7qwoqstjy

Memory-efficient algorithms for spatial network queries

S. Nutanong, H. Samet
2013 2013 IEEE 29th International Conference on Data Engineering (ICDE)  
on candidate objects around the query point.  ...  SWH is also extended to support the incremental distance semi-join (IDSJ) query, which is a multiple query point generalization of the kNN query.  ...  (vi) Performance evaluations using a real road network and experimental results showing that our proposed algorithm outperforms the two best existing competitors [5] , [21] for both kNN and IDSJ queries  ... 
doi:10.1109/icde.2013.6544863 dblp:conf/icde/NutanongS13 fatcat:pscdungjcvcdvnpf37jfd4jzqq

SALT. A unified framework for all shortest-path query variants on road networks [article]

Alexandros Efentakis, Dieter Pfoser, Yannis Vassiliou
2014 arXiv   pre-print
Although recent scientific output focuses on multiple shortest-path problem definitions for road networks, none of the existing solutions does efficiently answer all different types of SP queries.  ...  Our solution offers all the benefits needed for practical use-cases, including excellent query performance and very short preprocessing times, thus making it also a viable option for dynamic road networks  ...  The authors would also like to thank Ruicheng Zhong for providing us access to the G-tree source code.  ... 
arXiv:1411.0257v1 fatcat:c5s4dnbu4jdihe7yohzeilloqi

α-Probabilistic flexible aggregate nearest neighbor search in road networks using landmark multidimensional scaling

Moonyoung Chung, Woong-Kee Loh
2020 Journal of Supercomputing  
AbstractIn spatial database and road network applications, the search for the nearest neighbor (NN) from a given query object q is the most fundamental and important problem.  ...  The state-of-the-art FANN search algorithm in road networks, which is known as IER-$$k\hbox {NN}$$ k NN , used the Euclidean distance based on the two-dimensional coordinates of objects when choosing an  ...  This study proposes an efficient FANN search algorithm in road networks.  ... 
doi:10.1007/s11227-020-03521-6 fatcat:ifi6u5pzvbdohbixz2lug2tkku

k-nearest neighbors on road networks

Tenindra Abeywickrama, Muhammad Aamir Cheema, David Taniar
2016 Proceedings of the VLDB Endowment  
A k nearest neighbor (kNN) query on road networks retrieves the k closest points of interest (POIs) by their network distances from a given location.  ...  While Euclidean distance has been used as a heuristic to search for the closest POIs by their road network distance, its efficacy has not been thoroughly investigated.  ...  Kawata for valuable assistance in improving the code of PHL. We also thank the anonymous reviewers for their feedback through which we significantly improved our work.  ... 
doi:10.14778/2904121.2904125 fatcat:5qrmasyryvf5dhi7paivyrtmtm

k-Nearest Neighbors on Road Networks: A Journey in Experimentation and In-Memory Implementation [article]

Tenindra Abeywickrama, Muhammad Aamir Cheema, David Taniar
2016 arXiv   pre-print
A k nearest neighbor (kNN) query on road networks retrieves the k closest points of interest (POIs) by their network distances from a given location.  ...  While Euclidean distance has been used as a heuristic to search for the closest POIs by their road network distance, its efficacy has not been thoroughly investigated.  ...  Kawata for valuable assistance in improving the code of PHL. We also thank the anonymous reviewers for their feedback through which we significantly improved our work.  ... 
arXiv:1601.01549v2 fatcat:kj5llfoomnahnlgm2zsjeb2yzi

AES-Route Server Model for Location based Services in Road Networks

Mohamad Shady, Muhammad Usman, Adnan Abesen, Sabah Arif
2017 International Journal of Advanced Computer Science and Applications  
Additionally, the efficiency of spatial query processing, and the accuracy of said results, can be problematic when applied to road networks.  ...  The proposed model satisfies the primary goals including accuracy, efficiency and privacy for a location base system.  ...  Similarly for KNN query with given query point q with data set P on G road network, a K Nearest Neighbor (KNN) query determine the k objects in P whole network distance which is represented as follows:  ... 
doi:10.14569/ijacsa.2017.080847 fatcat:lx6ahjbshjbbdpe3lrtvkbdgba

Analytical queries on road networks

Shangfu Peng, Hanan Samet
2015 Proceedings of the 23rd SIGSPATIAL International Conference on Advances in Geographic Information Systems - GIS '15  
These queries require architectures that can compute a large number of network distances. Two architectures are evaluated on a variety of spatial analytical queries on road networks.  ...  A detailed evaluation of the two architectures for a variety of analytical query processing tasks such as region, KNN, distance matrix and trajectory queries is presented and the lessons learned are discussed  ...  Beyond simple navigation queries, location-based web services like Google Maps repeatedly pose queries on a road network and utilize the results to serve a user base.  ... 
doi:10.1145/2820783.2820806 dblp:conf/gis/PengS15 fatcat:gfiz343s4ffgzbkhnhrgwvaipa

Beyond Millisecond Latency $k$ NN Search on Commodity Machine

Bailong Liao, Leong Hou U, Man Lung Yiu, Zhiguo Gong
2015 IEEE Transactions on Knowledge and Data Engineering  
The k nearest neighbor (kNN) search on road networks is an important function in web mapping services.  ...  While overlay graph-based indices can answer shortest path queries efficiently, there have been no studies on utilizing such indices to answer kNN queries efficiently.  ...  algorithms for processing kNN queries on road networks.  ... 
doi:10.1109/tkde.2015.2426702 fatcat:326vjx5jxfdvze34nh4joxpt4q

Efficient reverse k-nearest neighbor estimation

Elke Achtert, Christian Böhm, Peer Kröger, Peter Kunath, Alexey Pryakhin, Matthias Renz
2007 Informatik - Forschung und Entwicklung  
Usually, these applications need a solution for the generalized problem where the value of k is not known in advance and may change from query to query.  ...  In this paper, we propose the first approach for efficient approximative RkNN search in arbitrary metric spaces where the value of k is specified at query time.  ...  In this paper, we propose an efficient approximate solution based on the hypersphere-approach for the RkNN problem.  ... 
doi:10.1007/s00450-007-0027-z fatcat:iiqfjtwprvcsvixyr6arpslwwm

Efficient Path Routing Over Road Networks in the Presence of Ad-Hoc Obstacles (Technical Report) [article]

Ahmed Al-Baghdadi, Xiang Lian, En Cheng
2019 arXiv   pre-print
Inspired by this, in this paper, we consider two types of ad-hoc obstacles, keyword-based and weather-based obstacles, on road networks, which can be used for modeling roads that the returned paths should  ...  In the presence of such ad-hoc obstacles on roads, we formulate a path routing query over road networks with ad-hoc obstacles (PRAO), which retrieves paths from source to destination on road networks that  ...  Apart from the shortest path query, many other query types have been studied in spatial road networks, for example, range queries [24, 25] , k-nearest neighbor (kNN) queries [26, 24] , k-nearest neighbor  ... 
arXiv:1910.04786v1 fatcat:o3num4panjedxiffyu4dyc2eoa

Indexing Fast Moving Objects for kNN Queries Based on Nearest Landmarks

Dan Lin, Rui Zhang, Aoying Zhou
2006 Geoinformatica  
Our approach is based on an important observation that queries usually occur around certain places or spatial landmarks of interest, called reference points.  ...  Note that the kNN query in moving objects databases is slightly different from the conventional kNN query for static data due to the consideration of the time parameter.  ...  The other is based on real road network in Singapore (see Figure 1 ). The generations consist of three steps as follows: First, we need to decide the reference points.  ... 
doi:10.1007/s10707-006-0341-9 fatcat:ig25hr34lvgbdouqakmishciki

Shortest path computation on air indexes

Georgios Kellaris, Kyriakos Mouratidis
2010 Proceedings of the VLDB Endowment  
Shortest path computation is one of the most common queries in location-based services that involve transportation networks.  ...  Although spatial problems have been considered in this environment, there exists no study on shortest path queries in road networks.  ...  APPENDIX A: SPATIAL AIR INDEXES For range and k nearest neighbor (kNN) queries, [16] presents the Hilbert curve index (HCI) method, which is based on the (1, m) interleaving scheme.  ... 
doi:10.14778/1920841.1920936 fatcat:dbwmqwfpbbebbj74qwj2kwq2am

Place recognition survey: An update on deep learning approaches [article]

Tiago Barros, Ricardo Pereira, Luís Garrote, Cristiano Premebida, Urbano J. Nunes
2021 arXiv   pre-print
This survey proceeds by elaborating on the various DL-based works, presenting summaries for each framework.  ...  ; or the increasing tendency of recent works to seek, not only for higher performance but also for higher efficiency.  ...  The CNN architecture is based on the VGG-F [105] , and the output features are further compressed using a random selection approach for efficient matching. 2) Landmark-based: Landmark-based approaches  ... 
arXiv:2106.10458v2 fatcat:hbw47qq2mjhsjhfb5t5vw4wfce

Probabilistic range queries for uncertain trajectories on road networks

Kai Zheng, Goce Trajcevski, Xiaofang Zhou, Peter Scheuermann
2011 Proceedings of the 14th International Conference on Extending Database Technology - EDBT/ICDT '11  
For these settings, we introduce a novel indexing mechanism -UTH (Uncertain Trajectories Hierarchy), based upon which efficient algorithms for processing spatio-temporal range queries are proposed.  ...  In this paper, we focus on representing the uncertainty of the objects moving along road networks as time-dependent probability distribution functions, assuming availability of a maximal speed on each  ...  ACKNOWLEDGEMENTS We wish to thank the anonymous reviewers for several comments and suggestions that have improved the paper.  ... 
doi:10.1145/1951365.1951400 dblp:conf/edbt/ZhengTZS11 fatcat:m5ezl546fvgfdlhsklzutncgna
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