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This paper derives a symbolic multi-body rigid nonlinear model for a space telescope using Stoneking's implementation of Kane's method. This symbolic nonlinear model is linearized using Matlab symbolic functions {\tt diff} and {\tt inv}…

Optimization and Control · Mathematics 2025-01-03 Yaguang Yang , William Bentz , Lia Lewis

This paper is devoted to the numerical approximation of a degenerate anisotropic elliptic problem. The numerical method is designed for arbitrary space-dependent anisotropy directions and does not require any specially adapted coordinate…

Numerical Analysis · Mathematics 2014-04-08 Stéphane Brull , Pierre Degond , Fabrice Deluzet

We describe a generalised method for ellipsoid fitting against a minimum set of data points. The proposed method is numerically stable and applies to a wide range of ellipsoidal shapes, including highly elongated and arbitrarily oriented…

Computer Vision and Pattern Recognition · Computer Science 2017-07-26 Amit Reza , Anand S. Sengupta

Spatially referenced data often have autocovariance functions with elliptical isolevel contours, a property known as geometric anisotropy. The anisotropy parameters include the tilt of the ellipse (orientation angle) with respect to a…

Statistics Theory · Mathematics 2021-10-04 Manolis P. Petrakis , Dionissios T. Hristopulos

The paper presents a numerical study for the finite element method with anisotropic meshes. We compare the accuracy of the numerical solutions on quasi-uniform, isotropic, and anisotropic meshes for a test problem which combines several…

Numerical Analysis · Mathematics 2014-11-20 Weizhang Huang , Lennard Kamenski , Jens Lang

This work proposes a novel, general and robust method of determining bond micromoduli for anisotropic linear elastic bond-based peridynamics. The problem of finding a discrete distribution of bond micromoduli that reproduces an anisotropic…

Computational Engineering, Finance, and Science · Computer Science 2021-05-31 Naveen Prakash

We prove weighted anisotropic analytic estimates for solutions of second order elliptic boundary value problems in polyhedra. The weighted analytic classes which we use are the same as those introduced by Guo in 1993 in view of establishing…

Analysis of PDEs · Mathematics 2025-08-01 Martin Costabel , Monique Dauge , Serge Nicaise

Among the general class of metric-affine theories of gravity, there is a special class conformed by those endowed with a projective symmetry. Perhaps the simplest manner to realise this symmetry is by constructing the action in terms of the…

General Relativity and Quantum Cosmology · Physics 2021-04-23 Jose Beltrán Jiménez , Daniel de Andrés , Adrià Delhom

Neutron and X-ray reflectometry are important methods for studying thin multilayer systems. The Parratt method and the method of characteristic matrices, also referred to as transfer matrices, are used for simulation, evaluation of…

Other Condensed Matter · Physics 2026-03-09 Szilárd Sajti , László Deák

The paper introduces a new estimation method for the standard linear regression model. The procedure is not driven by the optimisation of any objective function rather, it is a simple weighted average of slopes from observation pairs. The…

Econometrics · Economics 2024-02-27 Felix Chan , Laszlo Matyas

This paper deals with the numerical study of a strongly anisotropic heat equation. The use of standard schemes in this situation leads to poor results, due to the high anisotropy. Furthermore, the recently proposed Asymptotic-Preserving…

Numerical Analysis · Mathematics 2015-06-15 Jacek Narski , Maurizio Ottaviani

In this work a symmetry of universal finite-size scaling functions under a certain anisotropic scale transformation is postulated. This transformation connects the properties of a finite two-dimensional system at criticality with…

Statistical Mechanics · Physics 2009-11-07 Alfred Hucht

This paper presents an end-to-end differentiable algorithm for robust and detail-preserving surface normal estimation on unstructured point-clouds. We utilize graph neural networks to iteratively parameterize an adaptive anisotropic kernel…

Computer Vision and Pattern Recognition · Computer Science 2020-06-24 Jan Eric Lenssen , Christian Osendorfer , Jonathan Masci

New interpolation and quasi-interpolation operators of Cl\'ement- and Scott-Zhang-type are analyzed on anisotropic polygonal and polyhedral meshes. Since no reference element is available, an appropriate linear mapping to a reference…

Numerical Analysis · Mathematics 2019-10-29 Steffen Weißer

We propose a numerical strategy to generate the anisotropic meshes and select the appropriate stabilized parameters simultaneously for two dimensional convection-dominated convection-diffusion equations by stabilized continuous linear…

Numerical Analysis · Mathematics 2016-02-09 Yana Di , Hehu Xie , Xiaobo Yin

We present a method for dimensionally adaptive sparse trigonometric interpolation of multidimensional periodic functions belonging to a smoothness class of finite order. This method targets applications where periodicity must be preserved…

Numerical Analysis · Mathematics 2020-08-28 Zack Morrow , Miroslav Stoyanov

We present a novel shape-approximating anisotropic re-meshing algorithm as a geometric generalization of the adaptive moving mesh method. Conventional moving mesh methods reduce the interpolation error of a mesh that discretizes a given…

Computational Geometry · Computer Science 2023-06-21 Nicolas Nebel , Albert Chern

We present a simple and efficient anisotropic generalization of the semi-isotropic (two-integral) axisymmetric Jeans formalism which is used to model the stellar kinematics of galaxies. The following is assumed: (i) a constant mass-to-light…

Astrophysics · Physics 2008-12-06 Michele Cappellari

Background: Pose estimation of rigid objects is a practical challenge in optical metrology and computer vision. This paper presents a novel stochastic-geometrical modeling framework for object pose estimation based on observing multiple…

Computer Vision and Pattern Recognition · Computer Science 2024-06-04 Wolfgang Hoegele

This study presents a generalised least squares based method for fitting polygons and ellipses to data points. The method is based on a trigonometric fitness function that approximates a unit shape accurately, making it applicable to…

Computer Vision and Pattern Recognition · Computer Science 2023-10-20 Yiming Quan , Shian Chen