English
Related papers

Related papers: Polynomial preserving recovery for PHT-splines

200 papers

Preconditioned gradient iterations for very large eigenvalue problems are efficient solvers with growing popularity. However, only for the simplest preconditioned eigensolver, namely the preconditioned gradient iteration (or preconditioned…

Numerical Analysis · Mathematics 2011-08-12 Klaus Neymeyr

We consider an adaptive algorithm for finite element methods for the isogeometric analysis (IGAFEM) of elliptic (possibly non-symmetric) second-order partial differential equations in arbitrary space dimension $d\ge2$. We employ…

Numerical Analysis · Mathematics 2017-11-20 Gregor Gantner , Daniel Haberlik , Dirk Praetorius

This paper proposes an image interpolation algorithm exploiting sparse representation for natural images. It involves three main steps: (a) obtaining an initial estimate of the high resolution image using linear methods like FIR filtering,…

Computer Vision and Pattern Recognition · Computer Science 2013-08-07 H. Lakshman , W. -Q Lim , H. Schwarz , D. Marpe , G. Kutyniok , T. Wiegand

This work proposes and analyzes a compressed sensing approach to polynomial approximation of complex-valued functions in high dimensions. Of particular interest is the setting where the target function is smooth, characterized by a rapidly…

Numerical Analysis · Mathematics 2020-01-22 Abdellah Chkifa , Nick Dexter , Hoang Tran , Clayton G. Webster

We apply polynomial approximation methods -- known in the numerical PDEs context as spectral methods -- to approximate the vector-valued function that satisfies a linear system of equations where the matrix and the right hand side depend on…

Numerical Analysis · Mathematics 2013-05-21 Paul G. Constantine , David F. Gleich , Gianluca Iaccarino

We propose a new stochastic gradient method for optimizing the sum of a finite set of smooth functions, where the sum is strongly convex. While standard stochastic gradient methods converge at sublinear rates for this problem, the proposed…

Optimization and Control · Mathematics 2013-03-12 Nicolas Le Roux , Mark Schmidt , Francis Bach

Image restoration is typically addressed through non-convex inverse problems, which are often solved using first-order block-wise splitting methods. In this paper, we consider a general type of non-convex optimisation model that captures…

The focus of this work is on the development of an error-driven isogeometric framework, capable of automatically performing an adaptive simulation in the context of second- and fourth-order, elliptic partial differential equations defined…

Numerical Analysis · Mathematics 2020-04-22 Luca Coradello , Pablo Antolin , Rafael Vázquez , Annalisa Buffa

In this paper, we propose a parallel and scalable approach for geodesic distance computation on triangle meshes. Our key observation is that the recovery of geodesic distance with the heat method from [Crane et al. 2013] can be reformulated…

Graphics · Computer Science 2019-08-02 Jiong Tao , Juyong Zhang , Bailin Deng , Zheng Fang , Yue Peng , Ying He

In fringe projection profilometry, the high-order harmonics information of non-sinusoidal fringes will lead to errors in the phase estimation. In order to solve this problem, a point-wise posterior phase estimation (PWPPE) method based on…

Image and Video Processing · Electrical Eng. & Systems 2021-08-03 Cong Liu , Chuang Zhang , Zhuoyi Yin , Xiaopeng Liu , Zhihong Xu

In this article we develop an $hp$-adaptive refinement procedure for Trefftz discontinuous Galerkin methods applied to the homogeneous Helmholtz problem. Our approach combines not only mesh subdivision (h-refinement) and local basis…

Numerical Analysis · Mathematics 2017-11-01 Scott Congreve , Paul Houston , Ilaria Perugia

Polynomial interpolation is an important component of many computational problems. In several of these computational problems, failure to preserve positivity when using polynomials to approximate or map data values between meshes can lead…

Numerical Analysis · Mathematics 2025-05-01 Timbwaoga A. J. Ouermi , Robert M Kirby , Martin Berzins

An approach is proposed for recovering affine correspondences (ACs) from orientation- and scale-invariant, e.g. SIFT, features. The method calculates the affine parameters consistent with a pre-estimated epipolar geometry from the point…

Computer Vision and Pattern Recognition · Computer Science 2018-07-11 Daniel Barath

Port-Hamiltonian systems provide a highly-structured framework for modeling of physical systems. By definition, they encode a balance equation relating energy changes to supplied and dissipated energy. Capturing this energy balance in…

Numerical Analysis · Mathematics 2026-05-15 Aashutosh Sharma , Andreas Bartel , Manuel Schaller

We consider the problem of sampling from a posterior distribution arising in Bayesian inverse problems in science, engineering, and imaging. Our method belongs to the family of independence Metropolis-Hastings (IMH) sampling algorithms,…

Machine Learning · Computer Science 2026-05-19 Youguang Chen , George Biros

Isogeometric analysis is a powerful paradigm which exploits the high smoothness of splines for the numerical solution of high order partial differential equations. However, the tensor-product structure of standard multivariate B-spline…

Numerical Analysis · Mathematics 2023-02-01 Cesare Bracco , Carlotta Giannelli , Mario Kapl , Rafael Vázquez

The hyperparameter optimization of neural network can be expressed as a bilevel optimization problem. The bilevel optimization is used to automatically update the hyperparameter, and the gradient of the hyperparameter is the approximate…

Machine Learning · Computer Science 2022-12-14 Shuo Yang , Yang Jiao , Shaoyu Dou , Mana Zheng , Chen Zhu

We present and analyze a novel sparse polynomial technique for approximating high-dimensional Hilbert-valued functions, with application to parameterized partial differential equations (PDEs) with deterministic and stochastic inputs. Our…

Numerical Analysis · Mathematics 2020-01-22 Nick Dexter , Hoang Tran , Clayton Webster

In this paper, we investigate the problem of hyperspectral (HS) image spatial super-resolution via deep learning. Particularly, we focus on how to embed the high-dimensional spatial-spectral information of HS images efficiently and…

Computer Vision and Pattern Recognition · Computer Science 2022-09-14 Jinhui Hou , Zhiyu Zhu , Junhui Hou , Huanqiang Zeng , Jinjian Wu , Jiantao Zhou

Super-resolution is a classical problem in image processing, with numerous applications to remote sensing image enhancement. Here, we address the super-resolution of irregularly-sampled remote sensing images. Using an optimal interpolation…

Machine Learning · Statistics 2017-09-28 Manuel López-Radcenco , Ronan Fablet , Abdeldjalil Aïssa-El-Bey , Pierre Ailliot