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Good quality reconstruction and comprehension of a scene rely on 3D estimation methods. The 3D information was usually obtained from images by stereo-photogrammetry, but deep learning has recently provided us with excellent results for…

Computer Vision and Pattern Recognition · Computer Science 2021-08-02 Rémy Leroy , Pauline Trouvé-Peloux , Frédéric Champagnat , Bertrand Le Saux , Marcela Carvalho

We propose a variational form of the BDF2 method as an alternative to the commonly used minimizing movement scheme for the time-discrete approximation of gradient flows in abstract metric spaces. Assuming uniform semi-convexity --- but no…

Analysis of PDEs · Mathematics 2017-12-25 Daniel Matthes , Simon Plazotta

We proposed a formally exact, probabilistic method to assess the validity of the Thomas-Fermi potential for three-dimensional condensed matter systems where electron dynamics is constrained to the Fermi surface. Our method, which relies on…

Materials Science · Physics 2024-06-25 Gionni Marchetti

3D scene flow estimation aims to estimate point-wise motions between two consecutive frames of point clouds. Superpoints, i.e., points with similar geometric features, are usually employed to capture similar motions of local regions in 3D…

Computer Vision and Pattern Recognition · Computer Science 2023-05-05 Yaqi Shen , Le Hui , Jin Xie , Jian Yang

In this paper, we introduce a frequency-domain approach to extract information on the trajectory of a moving point source. The method hinges on the analysis of multi-frequency near-field data recorded at one and sparse observation points in…

Numerical Analysis · Mathematics 2025-08-25 Guanqiu Ma , Hongxia Guo , Guanghui Hu

The Fermat principle is used to define trajectories in nonhomogenous optical media. The Poincare model of the Lobachevskii geometry is derived. The index of refraction is determined for the light confined in the circular trajectory in the…

General Physics · Physics 2011-01-21 Miroslav Pardy

X-ray tomography is a powerful volumetric imaging technique, but detailed three dimensional (3D) imaging requires the acquisition of a large number of individual X-ray images, which is time consuming. For applications where spatial…

Image and Video Processing · Electrical Eng. & Systems 2023-02-28 Zhenduo Shang , Thomas Blumensath

A fully coupled system of two second-order parabolic degenerate equations arising as a thin film approximation to the Muskat problem is interpreted as a gradient flow for the 2-Wasserstein distance in the space of probability measures with…

Analysis of PDEs · Mathematics 2013-08-29 Philippe Laurencot , Bogdan-Vasile Matioc

We present an inverse method for designing a three-dimensional imaging system comprising of freeform optical surfaces. We impose an imaging condition on the optical map and combine it with the law of conservation of energy to conclude that…

A method of modelling the three-dimensional microstructure of random isotropic two-phase materials is proposed. The information required to implement the technique can be obtained from two-dimensional images of the microstructure. The…

Disordered Systems and Neural Networks · Physics 2009-10-31 Anthony Roberts

Computational difficulty of quadratic matching and the Gromov-Wasserstein distance has led to various approximation and relaxation schemes. One of such methods, relying on the notion of distance profiles, has been widely used in practice,…

Methodology · Statistics 2025-12-30 YoonHaeng Hur , Yuehaw Khoo

The contouring methods described by Lewis et al. (1993) and Witt (1993) are very efficient and elegant for obtaining the magnification of a point source moving along a straight track in the source plane. The method is, however, not very…

Astrophysics · Physics 2007-05-23 S. V. H. Haugan

We propose an extension of a special form of gradient descent -- in the literature known as linearised Bregman iteration -- to a larger class of non-convex functions. We replace the classical (squared) two norm metric in the gradient…

Optimization and Control · Mathematics 2021-05-26 Martin Benning , Marta M. Betcke , Matthias J. Ehrhardt , Carola-Bibiane Schönlieb

Efficient scene representations are essential for many computer graphics applications. A general unified representation that can handle both surfaces and volumes simultaneously, remains a research challenge. Inspired by recent methods for…

Graphics · Computer Science 2025-09-10 Jorge Condor , Sebastien Speierer , Lukas Bode , Aljaz Bozic , Simon Green , Piotr Didyk , Adrian Jarabo

3D Gaussian Splatting has gained widespread adoption across diverse applications due to its exceptional rendering performance and visual quality. While most existing methods rely on rasterization to render Gaussians, recent research has…

Graphics · Computer Science 2026-01-29 Junseo Lee , Sangyun Jeon , Jungi Lee , Junyong Park , Jaewoong Sim

Electromagnetism in an inhomogeneous dielectric medium at rest is described using the methods of differential geometry. In contrast to a general relativistic approach the electromagnetic fields are discussed in three-dimensional space only.…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Paul Piwnicki

Most end-to-end Multi-Object Tracking (MOT) methods face the problems of low accuracy and poor generalization ability. Although traditional filter-based methods can achieve better results, they are difficult to be endowed with optimal…

Computer Vision and Pattern Recognition · Computer Science 2021-03-08 Guangyao Zhai , Xin Kong , Jinhao Cui , Yong Liu , Zhen Yang

We propose a hybrid approach to solve the high-frequency Helmholtz equation with point source terms in smooth heterogeneous media. The method is based on the ray-based finite element method (ray-FEM), whose original version can not handle…

Numerical Analysis · Mathematics 2018-07-04 Jun Fang , Jianliang Qian , Leonardo Zepeda-Núñez , Hongkai Zhao

We report the development of a new ray-tracing simulation tool having the potential of the full characterization of a radio link through the accurate study of the propagation path of the signal from the transmitting to the receiving…

Computational Physics · Physics 2007-05-23 C. Tannous , J. Nigrin

Recent approaches for 3D object detection have made tremendous progresses due to the development of deep learning. However, previous researches are mostly based on individual frames, leading to limited exploitation of information between…

Computer Vision and Pattern Recognition · Computer Science 2020-09-15 Xusen Guo , Jiangfeng Gu , Silu Guo , Zixiao Xu , Chengzhang Yang , Shanghua Liu , Long Cheng , Kai Huang