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A subdivision-based algorithm for the sparse resultant

John F. Canny, Ioannis Z. Emiris
2000 Journal of the ACM  
Our algorithm uses a mixed polyhedral subdivision of the Minkowski sum of the Newton polytopes in order to construct a Newton matrix.  ...  We propose a determinantal formula for the sparse resultant of an arbitrary system of n + 1 polynomials in n variables.  ...  Berkeley, under the nancial support of a David and Lucile Packard Foundation Fellowship and of NSF Presidential Young Investigator Grant IRI-8958577. We thank Ashutosh Rege for useful discussions.  ... 
doi:10.1145/337244.337247 fatcat:z7z4myffu5a65m7jiug7jaeftu

Towards designing an optical-flow based colonoscopy tracking algorithm: a comparative study

Jianfei Liu, Kalpathi R. Subramanian, Terry S. Yoo, David R. Holmes, Ziv R. Yaniv
2013 Medical Imaging 2013: Image-Guided Procedures, Robotic Interventions, and Modeling  
SIFT and Harris a ne features resulted in tracking errors of up to 70mm, while our sparse optical flow error was 6mm.  ...  The comparative study demonstrated that our optical-flow based colonoscopy tracking algorithm maintains good accuracy and stability for routine use in clinical practice.  ...  Our optical flow based tracking algorithm (Fig. 1 ). Figs. 3(a) and 3(b) illustrate error curves for the two sequences.  ... 
doi:10.1117/12.2007956 dblp:conf/miigp/LiuSY13 fatcat:xwpe4jx43zcchfwqvo62au7bcm

An Improved Building Reconstruction Algorithm Based on Manhattan World Assumption and Line-Restricted Hypothetical Plane Fitting

Xiaoguo Zhang, Guo Wang, Ye Gao, Huiqing Wang, Qing Wang
2020 Mathematical Problems in Engineering  
Next, by using the normal direction obtained using the result of 3D line segment clustering, we propose a multihypothetical plane fitting algorithm based on the mean shift method.  ...  instead of the sparse and noisy seed points generated by PMVS itself.  ...  of dense points is a timeconsuming process and (2) based on sparse points and sparse 3D line segments [17] , and the corresponding issue of such algorithms is that the sparse point cloud reconstructed  ... 
doi:10.1155/2020/9267854 fatcat:ai7j6ttjuvcodoqu2k2yhg7buq

Sylvester-type matrices for sparse resultants

Shamsatun Nahar Ahmad, Nor'aini Aris
2014 Malaysian Journal of Fundamental and Applied Sciences  
The resultant matrix of a polynomial system depends on the geometry of its input Newton polytopes. Therefore for sparse inputs, the matrix is lower in dimension.  ...  sufficient condition for producing exact sparse resultants.  ...  The greedy variant of the subdivision based algorithm is named after Pederson [3] .  ... 
doi:10.11113/mjfas.v6n1.173 fatcat:zkmzdpodlbe3dn7mids2wkzr7e

Page 8719 of Mathematical Reviews Vol. , Issue 99m [page]

1999 Mathematical Reviews  
As the main result, the L p(R4 ) convergence of a subdivision scheme is characterized by the spectral radius of a certain operator associ- ated with the subdivision scheme.  ...  review various constructions for multi- variate integration formulas on sparse grids, based on the Newton- Cotes, Clenshaw-Curtis and Gauss formulas.  ... 

Fast visualization of volume emissions using conservative subdivision

Mats Holmström
2004 Mathematics and Computers in Simulation  
A sparse hierarchical wavelet-based representation of the directional volume emission rate function is constructed top-down and then projected onto the image plane.  ...  Since a sparse oct-tree is constructed for a specific view point the method is best suited to situations where one image is to be generated from each view point.  ...  Acknowledgements I thank Timothy Sergienko for helping me understand the nomenclature of radiometry.  ... 
doi:10.1016/j.matcom.2003.11.015 fatcat:izgloqm7krhuzkjufoj7qj3j5m

Three-Dimensional Data Compression with Anisotropic Diffusion [chapter]

Pascal Peter
2013 Lecture Notes in Computer Science  
This codec uses a cuboidal subdivision strategy to select and efficiently store a small set of sparse image data and reconstructs missing image parts with EED-based inpainting.  ...  An evaluation on real-world medical data substantiates the superior performance of this new algorithm in comparison to 2-D inpainting methods and the compression standard DICOM for medical data.  ...  Our 3-D compression algorithm is modelled after R-EED [8] , an algorithm that chooses sparse data with a rectangular subdivision scheme and fills in missing image parts with EED-based interpolation.  ... 
doi:10.1007/978-3-642-40602-7_24 fatcat:6hd6nzkmfzesbdb7fhvdkjgule

Structured Image Techniques for Efficient High-Fidelity Graphics [article]

X. Yang, K. Debattista, A. Chalmers
2006 Computer Graphics and Visual Computing  
In this paper, we present a selective rendering framework based on ray tracing for global illumination which uses a rapid image preview of the scene to identify important image regions, structures these  ...  By exploiting this prior knowledge of the scene and taking advantage of image space based algorithms to concentrate rendering on the more salient areas higher performance rendering may be achieved.  ...  The second step of the algorithm is to build a certainty map for the sparsely sampled image.  ... 
doi:10.2312/localchapterevents/tpcg/tpcg06/149-155 dblp:conf/tpcg/YangDC06 fatcat:tp26crutwvejfo6mkj7qbtk33e

A Survey on Arabic Character Recognition

Ahmed Lawgali
2015 International Journal of Signal Processing, Image Processing and Pattern Recognition  
An optimal subdivision of blocks of the sparse matrices is obtained by using a quad tree structure to inhibit the blocking artifacts.  ...  In order to effectively extract the focused regions from the source images and inhibit the blocking artifacts of the fused image, a novel adaptive block-based image fusion scheme based on sparse features  ...  And then the two sparse matrices A E and B E are split based on the split results of 0 E , respectively.  ... 
doi:10.14257/ijsip.2015.8.2.37 fatcat:nlcd7v2nardn7b7g4ngpchdcwq

Multi-focus Image Fusion Based on Sparse Features

Yongxin Zhang, Li Chen, Zhihua Zhao, Jian Jia
2014 International Journal of Signal Processing, Image Processing and Pattern Recognition  
An optimal subdivision of blocks of the sparse matrices is obtained by using a quad tree structure to inhibit the blocking artifacts.  ...  In order to effectively extract the focused regions from the source images and inhibit the blocking artifacts of the fused image, a novel adaptive block-based image fusion scheme based on sparse features  ...  Acknowledgements The work is supported by the National Key Technology Science and Technique Support Program  ... 
doi:10.14257/ijsip.2014.7.2.37 fatcat:lyievokhf5bftoperhoekjngii

Fast high-dimensional approximation with sparse occupancy trees

Peter Binev, Wolfgang Dahmen, Philipp Lamby
2011 Journal of Computational and Applied Mathematics  
For this purpose we propose new methods based on what we call sparse occupancy trees and piecewise linear schemes based on simplex subdivisions.  ...  This paper is concerned with scattered data approximation in high dimensions: Given a data set X ⊂ R d of N data points x i along with values y i ∈ R d ′ , i = 1, . . . , N, and viewing the y i as values  ...  In particular, he has introduced us to applications in meteorology which have been a major motivation for this work.  ... 
doi:10.1016/j.cam.2010.10.005 fatcat:olkin24whnfnfdpb3bc2aqaaze

Page 138 of American Society of Civil Engineers. Collected Journals Vol. 129, Issue 2 [page]

2003 American Society of Civil Engineers. Collected Journals  
In particular, we select the best candidate group for subdivision as the one that results in the greatest drop in the value of J after the group subdivision.  ...  The candidate group for subdivision is the one that results in the greatest drop in the value of the objective function J/(x).  ... 

Page 2368 of Mathematical Reviews Vol. , Issue 81F [page]

1981 Mathematical Reviews  
The main technical result of the paper is the corresponding lower bound on the complexity of Pg over the base {+, X}.  ...  Locating a point p in a subdivision means finding the subdivision region which contains p.  ... 

Generating contours on FEM/BEM higher-order surfaces using Java 3D textures

G.P. Nikishkov
2003 Advances in Engineering Software  
Subdivision density is defined on the basis of both face edge curvature and ranges of result fields over element faces. Java 3D API is employed for code development.  ...  Since results of high accuracy with significant gradients can be obtained using sparse meshes of boundary elements and finite elements, special attention is devoted to element face subdivision.  ...  The author would like to acknowledge the helpful discussion with Prof. N.N.Mirenkov at the University of Aizu.  ... 
doi:10.1016/s0965-9978(03)00052-8 fatcat:ionraes2yvefdfa63kygcknmry

A sparse partitioned-regression model for nonlinear system–environment interactions

Shuluo Ning, Eunshin Byon, Teresa Wu, Jing Li
2017 IISE Transactions  
We propose a Sparse Partitioned-Regression (SPR) model that automatically searches for a partition of the environmental variables and fits a sparse regression within each subdivision of the partition,  ...  An efficient recursive partition algorithm is developed for model estimation.  ...  In summary, the proposed SPR consists of four models: a sparse penalized estimator for prediction, a sparse held-out estimator for prediction, a sparse penalized estimator for classification, and a sparse  ... 
doi:10.1080/24725854.2017.1299955 fatcat:sgfyxob3qnbafdnosmgju3nore
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