Book ChapterDOI
Maximizing Reverse k-Nearest Neighbors for Trajectories
Tamjid Al Rahat,Arif Arman,Mohammed Eunus Ali +2 more
- pp 262-274
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TLDR
This paper introduces a generic similarity measure between a query object and a data object that helps to define the nearest neighbors according to user requirements, and proposes some pruning strategies that can quickly compute k-NNs (or top-k) facility trajectories for a given user trajectory.Abstract:
In this paper, we address a popular query involving trajectories, namely, the Maximizing Reverse k-Nearest Neighbors for Trajectories (MaxRkNNT) query. Given a set of existing facility trajectories (e.g., bus routes), a set of user trajectories (e.g., daily commuting routes of users) and a set of query facility trajectories (e.g., proposed new bus routes), the MaxRkNNT query finds the proposed facility trajectory that maximizes the cardinality of reverse k-Nearest Neighbors (NNs) set for the query trajectories. A major challenge in solving this problem is to deal with complex computation of nearest neighbors (or similarities) with respect to multi-point queries and data objects. To address this problem, we first introduce a generic similarity measure between a query object and a data object that helps us to define the nearest neighbors according to user requirements. Then, we propose some pruning strategies that can quickly compute k-NNs (or top-k) facility trajectories for a given user trajectory. Finally, we propose a filter and refinement technique to compute the MaxRkNNT. Our experimental results show that our proposed approach significantly outperforms the baseline for both real and synthetic datasets.read more
Citations
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Journal ArticleDOI
The maximum trajectory coverage query in spatial databases
Mohammed Eunus Ali,Shadman Saqib Eusuf,Kaysar Abdullah,Farhana M. Choudhury,J. Shane Culpepper,Timos Sellis +5 more
TL;DR: A novel index structure, the Trajectory Quadtree (TQ-tree) that utilizes a quadtree to hierarchically organize trajectories into different nodes, and then applies a z-ordering to further organize the trajectories by spatial locality inside each node is proposed.
Journal ArticleDOI
The Maximum Trajectory Coverage Query in Spatial Databases
Mohammed Eunus Ali,Kaysar Abdullah,Shadman Saqib Eusuf,Farhana M. Choudhury,J. Shane Culpepper,Timos Sellis +5 more
TL;DR: Wang et al. as discussed by the authors proposed a novel index structure, the Trajectory Quadtree (TQ-tree), which utilizes a quadtree to hierarchically organize trajectories into different quadtree nodes, and then applies a z-ordering to further organize the trajectories by spatial locality inside each node.
Journal ArticleDOI
Efficient Parallel K Best Connected Trajectory (K-BCT) Query with GPGPU: A Combinatorial Min-Distance and Progressive Bounding Box Approach
TL;DR: A progressive minimum bounding rectangle and minimum distance approach to process the K Best Connected Trajectory (K-BCT) query, which aims to find the top K similarity trajectories to a given query trajectory, which further leverages the many-core computing power of Graphical Processing Unit (GPU) devices to perform the query in a parallel manner.
Proceedings ArticleDOI
Cerberus
TL;DR: Cerberus as discussed by the authors is an automated static analyzer to find logical flaws and identify vulnerabilities in the implementation of OAuth service provider libraries, using a query-driven algorithm for answering queries about OAuth specifications.
Journal ArticleDOI
Maximizing the Influence of Bichromatic Reverse k Nearest Neighbors in Geo-Social Networks
TL;DR: A framework with carefully designed indexes, efficient batch BR k NN processing algorithms, and alternative POI selection policies that support both approximate and heuristic solutions are presented.
References
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Proceedings ArticleDOI
Discovering similar multidimensional trajectories
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Proceedings ArticleDOI
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Book ChapterDOI
On the marriage of Lp-norms and edit distance
Lei Chen,Raymond T. Ng +1 more
TL;DR: A new distance function, which is a marriage of L1- norm and the edit distance, ERP, which can support local time shifting, and is a metric, and dominates all existing strategies.
Proceedings ArticleDOI
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Book ChapterDOI
K-Nearest Neighbor Search for Moving Query Point
Zhexuan Song,Nick Roussopoulos +1 more
TL;DR: Four different methods are proposed for solving the problem of finding k nearest neighbors for moving query point, and the proposed algorithms always outperform the existing ones by fetching 70% less disk pages.