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Related papers: Hierarchical octree and k-d tree grids for 3D radi…

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Context: The Monte Carlo method is probably the most widely used approach to solve the radiative transfer problem, especially in a general 3D geometry. The physical processes of emission, absorption, and scattering are easily incorporated…

Astrophysics of Galaxies · Physics 2022-10-19 Maarten Baes , Peter Camps , Kosei Matsumoto

The representation of subgrid-scale orography is a challenge in the physical parameterization of orographic gravity-wave sources in weather forecasting. A significant hurdle is encoding as much physical information with as simple a…

Atmospheric and Oceanic Physics · Physics 2025-01-16 Ray Chew , Stamen Dolaptchiev , Maja-Sophie Wedel , Ulrich Achatz

A generalization of implicit conservative numerics to multiple dimensions requires advanced concepts of tensor analysis and differential geometry and hence a more thorough dedication to mathematical fundamentals than maybe expected at first…

Instrumentation and Methods for Astrophysics · Physics 2012-10-19 Harald Höller

We present an efficient MPI-parallel geometric multigrid library for quadtree (2D) or octree (3D) grids with adaptive refinement. Cartesian 2D/3D and cylindrical 2D geometries are supported, with second-order discretizations for the…

Computational Physics · Physics 2019-08-26 Jannis Teunissen , Rony Keppens

Data structures known as $k$-d trees have numerous applications in scientific computing, particularly in areas of modern statistics and data science such as range search in decision trees, clustering, nearest neighbors search, local…

Data Structures and Algorithms · Computer Science 2022-01-21 Aritra Chakravorty , William S. Cleveland , Patrick J. Wolfe

Being able to learn an effective semantic representation directly on raw point clouds has become a central topic in 3D understanding. Despite rapid progress, state-of-the-art encoders are restrictive to canonicalized point clouds, and have…

Computer Vision and Pattern Recognition · Computer Science 2022-08-12 Jun-Kun Chen , Yu-Xiong Wang

This paper proposes an efficient data structure, ikd-Tree, for dynamic space partition. The ikd-Tree incrementally updates a k-d tree with new coming points only, leading to much lower computation time than existing static k-d trees.…

Robotics · Computer Science 2021-02-23 Yixi Cai , Wei Xu , Fu Zhang

Diffusion models have recently emerged as a powerful tool for planning. However, unlike Monte Carlo Tree Search (MCTS)-whose performance naturally improves with inference-time computation scaling-standard diffusion-based planners offer only…

Artificial Intelligence · Computer Science 2026-01-30 Jaesik Yoon , Hyeonseo Cho , Doojin Baek , Yoshua Bengio , Sungjin Ahn

In this paper, we propose a new class of metric for table structure recognition (TSR) evaluation, called grid table similarity (GriTS). Unlike prior metrics, GriTS evaluates the correctness of a predicted table directly in its natural form…

Machine Learning · Computer Science 2023-05-25 Brandon Smock , Rohith Pesala , Robin Abraham

This work introduces an adaptive mesh refinement technique for hierarchical hybrid grids with the goal to reach scalability and maintain excellent performance on massively parallel computer systems. On the block structured hierarchical…

Numerical Analysis · Mathematics 2025-08-11 Benjamin Mann , Ulrich Rüde

Due to its accuracy and generality, Monte Carlo radiative transfer (MCRT) has emerged as the prevalent method for Ly$\alpha$ radiative transfer in arbitrary geometries. The standard MCRT encounters a significant efficiency barrier in the…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Aaron Smith , Benny T. -H. Tsang , Volker Bromm , Milos Milosavljevic

Oblique Decision Tree (ODT) separates the feature space by linear projections, as opposed to the conventional Decision Tree (DT) that forces axis-parallel splits. ODT has been proven to have a stronger representation ability than DT, as it…

Machine Learning · Computer Science 2025-02-04 Shen-Huan Lyu , Yi-Xiao He , Yanyan Wang , Zhihao Qu , Bin Tang , Baoliu Ye

With histograms as its foundation, we develop Categorical Exploratory Data Analysis (CEDA) under the extreme-$K$ sample problem, and illustrate its universal applicability through four 1D categorical datasets. Given a sizable $K$, CEDA's…

Applications · Statistics 2020-07-31 Elizabeth Chou , Catie McVey , Yin-Chen Hsieh , Sabrina Enriquez , Fushing Hsieh

Lidar datasets are becoming more and more common. They are appreciated for their precise 3D nature, and have a wide range of applications, such as surface reconstruction, object detection, visualisation, etc. For all this applications,…

Computer Vision and Pattern Recognition · Computer Science 2018-01-17 Remi Cura , Julien Perret , Nicolas Paparoditis

In this paper, we develop a multigrid method on unstructured shape-regular grids. For a general shape-regular unstructured grid of ${\cal O}(N)$ elements, we present a construction of an auxiliary coarse grid hierarchy on which a geometric…

Numerical Analysis · Mathematics 2014-10-09 Lars Grasedyck , Lu Wang , Jinchao Xu

Occupancy prediction has increasingly garnered attention in recent years for its fine-grained understanding of 3D scenes. Traditional approaches typically rely on dense, regular grid representations, which often leads to excessive…

Computer Vision and Pattern Recognition · Computer Science 2024-03-20 Yuhang Lu , Xinge Zhu , Tai Wang , Yuexin Ma

We present DART-Ray, a new ray-tracing 3D dust radiative transfer (RT) code designed specifically to calculate radiation field energy density (RFED) distributions within dusty galaxy models with arbitrary geometries. In this paper we…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 G. Natale , C. C. Popescu , R. J. Tuffs , D. Semionov

The basic idea of the kd-tree algorithm is to recursively partition a point set P by hyperplanes, and to store the obtained partitioning in a binary tree. Due to its immense popularity, many applications in astronomy have been implemented.…

Astrophysics · Physics 2008-01-15 Dan Gao , Yanxia Zhang , Yongheng Zhao

In this paper we introduce a new classification algorithm called Optimization of Distributions Differences (ODD). The algorithm aims to find a transformation from the feature space to a new space where the instances in the same class are as…

Machine Learning · Computer Science 2017-03-06 Mohammad Reza Bonyadi , Quang M. Tieng , David C. Reutens

A $k$-decision tree $t$ (or $k$-tree) is a recursive partition of a matrix (2D-signal) into $k\geq 1$ block matrices (axis-parallel rectangles, leaves) where each rectangle is assigned a real label. Its regression or classification loss to…

Machine Learning · Computer Science 2021-10-08 Ibrahim Jubran , Ernesto Evgeniy Sanches Shayda , Ilan Newman , Dan Feldman