Filters








592 Hits in 7.2 sec

Uncertain Voronoi cell computation based on space decomposition

Klaus Arthur Schmid, Andreas Zufle, Tobias Emrich, Matthias Renz, Reynold Cheng
2017 Geoinformatica  
Applications for possible Voronoi cells include geo-location-based services, such as taxi assignments: The possible Voronoi cell of an individual taxi cab c covers the space of a city where customers may  ...  Since exact computation of Voronoi cells is hard, we propose an approximate solution. The main idea of this solution is to apply hierarchical access methods for both data and object space.  ...  However, since we are using space approximation techniques, rather than computing exact bounds, we can avoid this computational drawback. Fig. 1 . 1 Uncertain Voronoi cells.  ... 
doi:10.1007/s10707-017-0293-2 fatcat:vi6cjszv7jfs5lq4zh5wcpyroy

Uncertain Voronoi Cell Computation Based on Space Decomposition [chapter]

Tobias Emrich, Klaus Arthur Schmid, Andreas Züfle, Matthias Renz, Reynold Cheng
2015 Lecture Notes in Computer Science  
Applications for possible Voronoi cells include geo-location-based services, such as taxi assignments: The possible Voronoi cell of an individual taxi cab c covers the space of a city where customers may  ...  Since exact computation of Voronoi cells is hard, we propose an approximate solution. The main idea of this solution is to apply hierarchical access methods for both data and object space.  ...  However, since we are using space approximation techniques, rather than computing exact bounds, we can avoid this computational drawback. Fig. 1 . 1 Uncertain Voronoi cells.  ... 
doi:10.1007/978-3-319-22363-6_6 fatcat:qc4qudhkavfpvai6namaslel2a

An adaptive minimum spanning tree multi-element method for uncertainty quantification of smooth and discontinuous responses [article]

Yous van Halder, Benjamin Sanderse, Barry Koren
2018 arXiv   pre-print
As a remedy we propose an adaptive sampling algorithm based on minimum spanning trees combined with a domain decomposition method based on support vector machines.  ...  The minimum spanning tree determines new sample locations based on both the probability density of the input parameters and the gradient in the quantity of interest.  ...  A Voronoi diagram is a partitioning of a d-dimensional space into regions based on the distance to a specific set of samples [31] .  ... 
arXiv:1803.06833v1 fatcat:idteuqytlzctpozcl6zti2a22m

Distributed area coverage control with imprecise robot localization: Simulation and experimental studies [article]

Sotiris Papatheodorou, Anthony Tzes, Konstantinos Giannousakis and Yiannis Stergiopoulos
2016 arXiv   pre-print
The convex-space is partitioned based on the Guaranteed Voronoi (GV) principle and each robot's area of responsibility corresponds to its GV-cell, bounded by hyperbolic arcs.  ...  A gradient ascent based control law was designed based on a Guaranteed Voronoi partition of the region.  ...  The Voronoi and the Guaranteed Voronoi space partitions are examined in Section III.  ... 
arXiv:1612.04704v1 fatcat:2blsek72drfh5e2xn37lgefq2y

Multi-robot terrain coverage and task allocation for autonomous detection of landmines

Prithviraj Dasgupta, Angélica Muñoz-Meléndez, K. R. Guruprasad, Edward M. Carapezza
2012 Sensors, and Command, Control, Communications, and Intelligence (C3I) Technologies for Homeland Security and Homeland Defense XI  
First, we describe a distributed and robust terrain coverage algorithm that employs Voronoi partitions to divide the area of interest among the robots and then uses a single-robot coverage algorithm to  ...  Multi-robot systems comprising of heterogeneous autonomous vehicles on land, air, water are being increasingly used to assist or replace humans in different hazardous missions.  ...  In a space which is descretized into cells based on the sensor/tool footprint, complete coverage task is achieved if each cell is visited by at least one robot.  ... 
doi:10.1117/12.919461 fatcat:phzslm4vv5drxogg65zsf3aeti

Decentralized Probabilistic Multi-Robot Collision Avoidance Using Buffered Uncertainty-Aware Voronoi Cells [article]

Hai Zhu, Bruno Brito, Javier Alonso-Mora
2022 arXiv   pre-print
In particular, at each time step, we construct a chance-constrained buffered uncertainty-aware Voronoi cell (B-UAVC) for each robot given a specified collision probability threshold.  ...  The approach relies on the computation of an uncertainty-aware safe region for each robot to navigate among other robots and static obstacles in the environment, under the assumption of Gaussian-distributed  ...  (a) Deterministic Voronoi cell (VC, the boundary in gray solid line). (b) Uncertainty-aware Voronoi cell based on the best linear separators (UAVC, the boundary in blue dashed line).  ... 
arXiv:2201.04012v1 fatcat:l5cabmxjpngijm6o6njzf3abzm

Voronoi Partition to Support Data Search in Uncertain Database with k-Bound Filtering

Slamet Sudaryanto Nurhendratno, Sudaryanto, Solichul Huda
2020 Journal of Computer Science  
With the development of mobile technology, one of its main functions is to have mobile navigation capabilities, this is one of the Location-Based Services (LBS).  ...  Efficient query processing is needed on a set of mobile data due to the movement of users. This movement has an impact on searching in an uncertain database.  ...  Voronoi diagram is the decomposition of space and fields according to the position of a set of discrete points (sites).  ... 
doi:10.3844/jcssp.2020.1753.1764 fatcat:s54uj4ohibdulc7ssqxeii4ozu

Optimum Reject Options for Prototype-based Classification [article]

Lydia Fischer, Barbara Hammer, Heiko Wersing
2015 arXiv   pre-print
We compare reject schemes with global thresholds, and local thresholds for the Voronoi cells of the classifier.  ...  For the latter, we develop a polynomial-time algorithm to compute optimum thresholds based on a dynamic programming scheme, and we propose an intuitive linear time, memory efficient approximation thereof  ...  Following the suggestion in [50] , we use the natural decomposition of the input space into the Voronoi-cells V j as introduced in Eq. (2).  ... 
arXiv:1503.06549v1 fatcat:zyisrb52zbf6bn7qiajqqzommy

Sensitivity Analysis for Microscopic Crowd Simulation

Marion Gödel, Rainer Fischer, Gerta Köster
2020 Algorithms  
Additionally, we identify a one-dimensional subspace in the input parameter space and discuss its impact on the simulation.  ...  In this work, we first perform a variance-based sensitivity analysis using Sobol' indices and then crosscheck the results by a derivative-based measure, the activity scores.  ...  Acknowledgments: The authors would like to thank Mario Teixeira Parente for discussions on active subspaces and activity scores.  ... 
doi:10.3390/a13070162 fatcat:neintnnpw5fddan3sdnvd77u64

VGQ-Vor: extending virtual grid quadtree with Voronoi diagram for mobile k nearest neighbor queries over mobile objects

Botao Wang, Jingwei Qu, Xiaosong Wang, Guoren Wang, Masaru Kitsuregawa
2012 Frontiers of Computer Science  
Our approach is based on an observation that the frequency of one region changing between being occupied or not by mobile objects is much lower than the frequency of the position changes reported by the  ...  We first propose an virtual grid quadtree with Voronoi diagram (VGQ-Vor), which is a two-layer index structure that indexes regions occupied by mobile objects in a quadtree and builds a Voronoi diagram  ...  Voronoi diagram A Voronoi diagram is a special kind of decomposition of a given space determined by the distances to a specified family of objects (subsets) in the space [22] .  ... 
doi:10.1007/s11704-012-2069-z fatcat:7r2zv2l6nbdjthxwzzbtau2xn4

Nearest-neighbor searching under uncertainty

Pankaj K. Agarwal, Alon Efrat, Swaminathan Sankararaman, Wuzhou Zhang
2012 Proceedings of the 31st symposium on Principles of Database Systems - PODS '12  
We present methods for computing an exact ENN or an εapproximate ENN, for a given error parameter 0 < ε < 1, under different distance functions.  ...  In many of these applications, such as sensor databases, location based services, face recognition, and mobile data, the location of data is imprecise.  ...  All of these methods were based on heuristics and did not provide any guarantee on the query time in the worst case.  ... 
doi:10.1145/2213556.2213588 dblp:conf/pods/AgarwalESZ12 fatcat:44gjybtmb5egfmnbspwjxseyba

Dynamic Nearest Neighbor Queries in Euclidean Space [chapter]

Sarana Nutanong, Mohammed Eunus Ali, Egemen Tanin, Kyriakos Mouratidis
2015 Encyclopedia of GIS  
One important variant of this query type is kNN query, which returns k data  ...  (c) Second-order Voronoi diagram of D Neighbor Queries in Euclidean Space, Fig. 3 Locally compute a kVD cell (k D 1). (a) Step 1. (b) Steps 2 and 3. (c) Steps 4 and 5.  ...  The Voronoi diagram is a well-known space decomposition technique determined by distances to a given discrete set of objects, typically a set of points.  ... 
doi:10.1007/978-3-319-23519-6_1558-1 fatcat:djuqr3v7k5g2jjvbd3xailxn2i

Dynamic Nearest Neighbor Queries in Euclidean Space [chapter]

Sarana Nutanong, Mohammed Eunus Ali, Egemen Tanin, Kyriakos Mouratidis
2017 Encyclopedia of GIS  
One important variant of this query type is kNN query, which returns k data  ...  (c) Second-order Voronoi diagram of D Neighbor Queries in Euclidean Space, Fig. 3 Locally compute a kVD cell (k D 1). (a) Step 1. (b) Steps 2 and 3. (c) Steps 4 and 5.  ...  The Voronoi diagram is a well-known space decomposition technique determined by distances to a given discrete set of objects, typically a set of points.  ... 
doi:10.1007/978-3-319-17885-1_1558 fatcat:425f2o25ynhwno5renou66xpci

Approximate Evaluation of Range Nearest Neighbor Queries with Quality Guarantee [chapter]

Chi-Yin Chow, Mohamed F. Mokbel, Joe Naps, Suman Nath
2009 Lecture Notes in Computer Science  
Examples of the applications of range NN queries include uncertain locations and privacy-preserving queries.  ...  The range nearest-neighbor (NN) query is an important query type in location-based services, as it can be applied to the case that an NN query has a spatial region, instead of a location point, as the  ...  Given a set of points S on the plane, which are the Voronoi sites, the Voronoi diagram of S, denoted as V (S), is a decomposition of the space into disjoint regions, cells, such that each site s i is associated  ... 
doi:10.1007/978-3-642-02982-0_19 fatcat:jqo72xnz2fh6jelhoe7a6asx44

High-Dimensional Uncertainty Quantification via Tensor Regression with Rank Determination and Adaptive Sampling [article]

Zichang He, Zheng Zhang
2021 arXiv   pre-print
Our method considers both exploration and exploitation via the estimated Voronoi cell volume and nonlinearity measurement respectively.  ...  The proposed model is verified with synthetic and some realistic circuit benchmarks, on which our method can well capture the uncertainty caused by 19 to 100 random variables with only 100 to 600 simulation  ...  X , the surrogate on a sample ξ can be efficiently calculated aŝ Based on the above observation, we estimate the volume of Voronoi cell in the hyper cube.  ... 
arXiv:2103.17236v2 fatcat:pxkd53ojnval5dnp5nw7yajmgi
« Previous Showing results 1 — 15 out of 592 results