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相关论文: Using 3D Voronoi grids in radiative transfer simul…

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We present RAYTHEIA, a high-performance reverse ray-tracing algorithm designed to efficiently solve three-dimensional direction-dependent equations in astronomical simulations. The algorithm uses a dual-grid framework in which the native…

天体物理仪器与方法 · 物理学 2026-05-12 Zhengping Zhu , Thomas G. Bisbas , Xuefei Tang , Brandt A. L. Gaches , Tianwei Zhang , Huaxi Chen

We extend the Geometric Refinement Transform (GRT) by introducing centroidal Voronoi tessellations (CVTs) into the refinement process, enhancing symmetry, reconstruction accuracy, and numerical stability. By applying Lloyds algorithm at…

数值分析 · 数学 2025-03-28 Zachary Mullaghy

Any system of bisectors (in the sense of abstract Voronoi diagrams) defines an arrangement of simple curves in the plane. We define Voronoi-like graphs on such an arrangement, which are graphs whose vertices are locally Voronoi. A vertex…

计算几何 · 计算机科学 2023-03-14 Evanthia Papadopoulou

Volumetric shape representations have become ubiquitous in multi-view reconstruction tasks. They often build on regular voxel grids as discrete representations of 3D shape functions, such as SDF or radiance fields, either as the full shape…

计算机视觉与模式识别 · 计算机科学 2024-10-01 Diego Thomas , Briac Toussaint , Jean-Sebastien Franco , Edmond Boyer

We present a ray-tracing technique for radiative transfer modeling of complex three-dimensional (3D) structures which include dense regions of high optical depth like in dense molecular clouds, circumstellar disks, envelopes of evolved…

天体物理学 · 物理学 2009-11-11 J. Steinacker , A. Bacmann , Th. Henning

Given a set of $n$ sites from $\mathbb{R}^d$, each having some positive weight factor, the Multiplicatively Weighted Voronoi Diagram is a subdivision of space that associates each cell to the site whose weighted Euclidean distance is…

计算几何 · 计算机科学 2024-03-19 Joachim Gudmundsson , Martin P. Seybold , Sampson Wong

A numerically efficient, accurate, and easily implemented integration scheme over convex Voronoi polyhedra (VP) is presented for use in {\it ab-initio} electronic-structure calculations. We combine a weighted Voronoi tessellation with…

材料科学 · 物理学 2013-12-25 Aftab Alam , S. N. Khan , Brian G. Wilson , D. D. Johnson

Unstructured Voronoi mesh simulations offer many advantages for simulating self-gravitating gas dynamics on galactic scales. Adaptive mesh refinement (AMR) can be a powerful tool for simulating the details of star cluster formation and gas…

Voronoi intensity estimators, which are non-parametric estimators for intensity functions of point processes, are both parameter-free and adaptive; the intensity estimate at a given location is given by the reciprocal size of the…

统计方法学 · 统计学 2018-07-10 M. Mehdi Moradi , Ottmar Cronie , Ege Rubak , Raphael Lachieze-Rey , Jorge Mateu , Adrian Baddeley

We study the problem of computing the Voronoi diagram of a set of $n^2$ points with $O(\log n)$-bit coordinates in the Euclidean plane in a substantially sublinear in $n$ number of rounds in the congested clique model with $n$ nodes.…

计算几何 · 计算机科学 2024-04-10 Jesper Jansson , Christos Levcopoulos , Andrzej Lingas

The development of radiation hydrodynamical methods that are able to follow gas dynamics and radiative transfer self-consistently is key to the solution of many problems in numerical astrophysics. Such fluid flows are highly complex, rarely…

A Voronoi diagram partitions the plane into convex cells, each containing the points closest to a single generator. Given such a tessellation, the inverse Voronoi problem seeks the generator set \( S \) that produced it. Our algorithm…

度量几何 · 数学 2025-06-25 Carlos M Hernandez-Suarez

Overset methods are commonly employed to enable the effective simulation of problems involving complex geometries and moving objects such as rotorcraft. This paper presents a novel overset domain connectivity algorithm based upon the direct…

计算物理 · 物理学 2018-11-14 Jacob A. Crabill , Freddie D. Witherden , Antony Jameson

Sampling-based motion-planning algorithms typically rely on nearest-neighbor (NN) queries when constructing a roadmap. Recent results suggest that in various settings NN queries may be the computational bottleneck of such algorithms.…

机器人学 · 计算机科学 2014-09-30 Michal Kleinbort , Oren Salzman , Dan Halperin

The manuscript describes fast and scalable architectures and associated algorithms for computing convolutions and cross-correlations. The basic idea is to map 2D convolutions and cross-correlations to a collection of 1D convolutions and…

硬件体系结构 · 计算机科学 2021-12-28 Cesar Carranza , Daniel Llamocca , Marios Pattichis

In this work we investigate numerically the reconstruction approach proposed in Goncharov, Novikov, 2016, for weighted ray transforms (weighted Radon transforms along oriented straight lines) in 3D. In particular, the approach is based on a…

数值分析 · 数学 2020-02-18 Fedor Goncharov

The broadband line-by-line analysis of radiative transfer in the atmosphere is extremely demanding with regard to computational resources. As a remedy, we present here the calculation of uniform error bounds for approximating the classical…

大气与海洋物理 · 物理学 2021-06-30 Sven Nordebo

We describe a set of techniques for performing large scale ab initio calculations using multigrid accelerations and a real-space grid as a basis. The multigrid methods provide effective convergence acceleration and preconditioning on all…

mtrl-th · 物理学 2008-02-03 E. L. Briggs , D. J. Sullivan , J. Bernholc

3D detailed radiative transfer is computationally taxing, since the solution of the radiative transfer equation involves traversing the six dimensional phase space of the 3D domain. With modern supercomputers the hardware available for…

太阳与恒星天体物理 · 物理学 2021-02-05 Peter H. Hauschildt , E. Baron

Adaptive binning is a crucial step in the analysis of large astronomical datasets, such as those from integral-field spectroscopy, to ensure a sufficient signal-to-noise ratio (S/N) for reliable model fitting. However, the widely used…

天体物理仪器与方法 · 物理学 2025-11-12 Michele Cappellari