Filters








141,570 Hits in 5.7 sec

Using R-Trees for Interactive Visualization of Large Multidimensional Datasets [chapter]

Alfredo Giménez, René Rosenbaum, Mario Hlawitschka, Bernd Hamann
2010 Lecture Notes in Computer Science  
Visualization interfaces are constrained in resolution and dimension, so cluttering and problems of projecting many dimensions into the available low dimensions are inherent.  ...  bounding hyperboxes of internal R-tree nodes.  ...  We thank our colleagues from the Institute of Data Analysis and Visualization (IDAV) at UC Davis.  ... 
doi:10.1007/978-3-642-17274-8_54 fatcat:sswx246gvvcnvawpwticlmj55u

Highway Dimension, Shortest Paths, and Provably Efficient Algorithms [chapter]

Ittai Abraham, Amos Fiat, Andrew V. Goldberg, Renato F. Werneck
2010 Proceedings of the Twenty-First Annual ACM-SIAM Symposium on Discrete Algorithms  
We show that low highway dimension gives provable guarantees of efficiency for the following algorithms (sometimes with small modifications): reach (RE), contraction hierarchies (CH), highway hierarchies  ...  We introduce the notion of highway dimension and show how low highway dimension gives a unified explanation for several seemingly different algorithms.  ...  Acknowledgments We would like to thank Daniel Delling for suggesting the use of highway dimension in the analysis of the SHARC algorithm.  ... 
doi:10.1137/1.9781611973075.64 dblp:conf/soda/AbrahamFGW10 fatcat:7clqlztjo5hhfmerde3cuj4rwu

Collision detection for deforming necklaces

Leonidas Guibas, An Nguyen, Daniel Russel, Li Zhang
2002 Proceedings of the eighteenth annual symposium on Computational geometry - SCG '02  
In particular, we achieve an upper bound of O(n log n) in two dimensions and O(n 2−2/d ) in d-dimensions, d ≥ 3, for collision checking.  ...  This hierarchy can be used for collision and self-collision detection.  ...  Acknowledgments The authors wish to thank PankajAgarwal for his contributions to the results of this paper. Discussions with John Hershberger, Menelaos Karavelas, Rachel Kolodny, and Man-Cho A.  ... 
doi:10.1145/513400.513405 dblp:conf/compgeom/GuibasNRZ02 fatcat:g3jp753qdza6xi6ofjgmajp45m

A hierarchical method for real-time distance computation among moving convex bodies

Leonidas J. Guibas, David Hsu, Li Zhang
2000 Computational geometry  
For convex polygons, we prove that H-Walk improves on the classic Lin-Canny and Dobkin-Kirkpatrick algorithms. We have implemented H-Walk for moving convex polyhedra in three dimensions.  ...  If the time step is small enough, the closest pair of features (vertices, edges or faces) between two polyhedra will not move very far from one time step to the next.  ...  Acknowledgements We would like to thank Brian Mirtich for helpful discussion of the collision detection problem and for providing us an implementation for the V-Clip algorithm.  ... 
doi:10.1016/s0925-7721(99)00042-5 fatcat:ylgvqqxjgbarjbly4lrtek6jly

W-Hardness Under Linear FPT-Reductions: Structural Properties and Further Applications [chapter]

Jianer Chen, Xiuzhen Huang, Iyad A. Kanj, Ge Xia
2005 Lecture Notes in Computer Science  
The notion of linear fpt-reductions has been recently used to derive strong computational lower bounds for well-known NP-hard problems.  ...  In this paper, we formally investigate the notions of W [t]-hardness and W [t]-completeness under the linear fpt-reduction, and study structural properties of the corresponding complexity classes.  ...  class logsnp, and that v-c dimension is complete under the polynomial time reduction for the class lognp.  ... 
doi:10.1007/11533719_98 fatcat:ewojc2i2z5gbllf6ynfulngu2a

H-Walk

Leonidas J. Guibas, David Hsu, Li Zhang
1999 Proceedings of the fifteenth annual symposium on Computational geometry - SCG '99  
For convex polygons, we prove that H-Walk improves on the classic Lin-Canny and Dobkin-Kirkpatrick algorithms. We have implemented H-Walk for moving convex polyhedra in three dimensions.  ...  This paper presents the Hierarchical Walk, or H-Walk algorithm, which maintains the distance between two moving convex bodies by exploiting both motion coherence and hierarchical representations.  ...  Acknowledgment We would like to thank Brian Mirtich for helpful discussion of the collision detection problem and for providing us an implementation for the V-Clip algorithm.  ... 
doi:10.1145/304893.304979 dblp:conf/compgeom/GuibasHZ99 fatcat:wkw554g4bfgyjkyr2yrl2gb4gy

Deep Hierarchical Super-Resolution for Scientific Data Reduction and Visualization [article]

Skylar W. Wurster, Han-Wei Shen, Hanqi Guo, Thomas Peterka, Mukund Raj, Jiayi Xu
2021 arXiv   pre-print
We train a hierarchy of neural networks, each capable of 2x upscaling in each spatial dimension between two levels of detail, and use these networks in tandem to facilitate large scale factor super resolution  ...  We present an approach for hierarchical super resolution (SR) using neural networks on an octree data representation.  ...  , O(DS) is the time complexity for the downscaling algorithm, and O(SR) is the time complexity for the super resolution algorithm.  ... 
arXiv:2107.00462v1 fatcat:37qe5d6v4bgrzb3cy5fnzf2qjm

Hierarchical Heavy Hitters with the Space Saving Algorithm [article]

Michael Mitzenmacher, Thomas Steinke, Justin Thaler
2011 arXiv   pre-print
It improves on the worst-case time and space bounds of earlier algorithms, is conceptually simple and substantially easier to implement, offers improved accuracy guarantees, is easily adopted to a distributed  ...  in terms of space, while our one-dimensional algorithm is also superior in terms of speed and accuracy for a more limited range of parameters.  ...  We thank Elaine Angelino, Richard Bates, and Graham Cormode for helpful discussions.  ... 
arXiv:1102.5540v2 fatcat:2exoilbqwnfihnaac44edms6aa

Lower Bounds in the Preprocessing and Query Phases of Routing Algorithms [article]

Colin White
2015 arXiv   pre-print
In 2010, Abraham et al. showed upper bounds on the query time in terms of a graph's highway dimension and diameter for the current fastest routing algorithms, including contraction hierarchies, transit  ...  We also show how to improve a result by Milosavljevic which lower bounds the number of shortcuts added in the preprocessing stage for contraction hierarchies.  ...  We would like to give a huge thanks to Lyle McGeoch for helpful discussions and suggestions throughout the writing process. We are grateful for the Post-Baccalaureate  ... 
arXiv:1501.04262v2 fatcat:42p7ddv3n5eszl3v47lfhx7bum

Sharp metastability threshold for an anisotropic bootstrap percolation model

H. Duminil-Copin, A. C. D. Van Enter
2013 Annals of Probability  
At each time step, sites that are occupied remain occupied, while sites that are not occupied become occupied if and only if three of more sites in their neighborhood are occupied.  ...  At time 0, sites are occupied with probability p.  ...  The first author would like to thank Stanislav Smirnov for his constant support.  ... 
doi:10.1214/11-aop722 fatcat:ogmteyvftrg6rfrc2e2ltieyty

Finding hierarchical heavy hitters in streaming data

Graham Cormode, Flip Korn, S. Muthukrishnan, Divesh Srivastava
2008 ACM Transactions on Knowledge Discovery from Data  
Data items that arrive online as streams typically have attributes which take values from one or more hierarchies (time and geographic location; source and destination IP addresses; etc.).  ...  Our algorithms exploit this structure, and so are able to to track approximate HHHs using only a small, fixed number of statistics per stored item, regardless of the number of dimensions.  ...  For two dimensions, we have a product of hierarchies.  ... 
doi:10.1145/1324172.1324174 fatcat:drdnstmp2nde7mhf3yisejx6lu

Brane World Confronts Holography [article]

Deog Ki Hong
2004 arXiv   pre-print
We discuss the implications for extra dimensions as well as holography.  ...  The thermodynamic entropy of astrophysical black holes and sub-horizon volumes during big bang nucleosynthesis exceed the relevant bounds unless M_* > 10^(4-6) TeV, so a hierarchy relative to the weak  ...  INTRODUCTION The idea that our universe might have extra dimensions beyond four space-time dimensions dates long back to early last century.  ... 
arXiv:hep-th/0401060v1 fatcat:whakeopsdnbj3ismbxqsayzmjq

Collision detection for deforming necklaces*1

P AGARWAL
2004 Computational geometry  
Using this hierarchy, we achieve a collision detection upper bound of O(n log n) in two dimensions and O(n 2−2/d ) in d-dimensions, d 3.  ...  In particular, we study a bounding volume hierarchy based on spheres which can be used for collision and self-collision detection of deforming and moving necklaces.  ...  Acknowledgements The authors wish to thank John Hershberger, Menelaos Karavelas, Rachel Kolodny, and Antony So for their helpful discussions and Erik Lindhahl for the molecular simulation data.  ... 
doi:10.1016/s0925-7721(04)00027-6 fatcat:s6bi6mizfbgr3oc6nnzmac4foi

Collision detection for deforming necklaces

Pankaj Agarwal, Leonidas Guibas, An Nguyen, Daniel Russel, Li Zhang
2004 Computational geometry  
Using this hierarchy, we achieve a collision detection upper bound of O(n log n) in two dimensions and O(n 2−2/d ) in d-dimensions, d 3.  ...  In particular, we study a bounding volume hierarchy based on spheres which can be used for collision and self-collision detection of deforming and moving necklaces.  ...  Acknowledgements The authors wish to thank John Hershberger, Menelaos Karavelas, Rachel Kolodny, and Antony So for their helpful discussions and Erik Lindhahl for the molecular simulation data.  ... 
doi:10.1016/j.comgeo.2004.03.008 fatcat:usdp2fuj5vh5jktnc3z66mvhma

Subquadratic encodings for point configurations

Jean Cardinal, Timothy M. Chan, John Iacono, Stefan Langerman, Aurélien Ooms
2019 Journal of Computational Geometry  
Finally, we generalize our results to the encoding of point configurations in higher dimension.  ...  \(O(\log n)\) time in the word-RAM model with word size \(w \geq \log n\).  ...  Correctness and Query Complexity As before, a query is answered by traversing the hierarchy, which takes O(log n) time.  ... 
doi:10.20382/jocg.v10i2a6 dblp:journals/jocg/CardinalCILO19 fatcat:lj3ldokeo5gm7l2sbh55nesnvy
« Previous Showing results 1 — 15 out of 141,570 results