English
Related papers

Related papers: NMAGIC: Fast Parallel Implementation of a Chi-Squa…

200 papers

The parallel code NMAGIC is an implementation of a particle-based method to create made-to-measure models in agreement with observations of galaxies. It works by slowly correcting the particle weights of an evolving N-body system, until a…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-30 Lucia Morganti , Ortwin Gerhard

Made-to-measure methods such as the parallel code NMAGIC are powerful tools to build galaxy models reproducing observational data. They work by adapting the particle weights in an N-body system until the target observables are well matched.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Lucia Morganti , Ortwin Gerhard

We describe an algorithm for constructing N-body realisations of equilibrium stellar systems. The algorithm complements existing orbit-based modelling techniques using linear programming or other optimization algorithms. The equilibria are…

Astrophysics · Physics 2015-06-24 D. Syer , S. Tremaine

We have developed the initial version of a new particle-by-particle adaptation of the made-to-measure (M2M) method, aiming to model the Galactic disc from upcoming Galactic stellar survey data. In our new particle-by-particle M2M, the…

Astrophysics of Galaxies · Physics 2015-06-11 Jason A. S. Hunt , Daisuke Kawata

We enhance the Syer & Tremaine made-to-measure (M2M) particle method of stellar dynamical modelling to model simultaneously both kinematic data and absorption line strength data thus creating a `chemo-M2M' modelling scheme. We apply the…

Astrophysics of Galaxies · Physics 2016-12-14 Richard Long

We investigate how accurately phase space distribution functions (DFs) in galactic models can be reconstructed by a made-to-measure (M2M) method, which constructs $N$-particle models of stellar systems from photometric and various kinematic…

Astrophysics of Galaxies · Physics 2016-08-24 Hiromichi Tagawa , Naoteru Gouda , Taihei Yano , Takuji Hara

We present an algorithm for quickly generating multiple realizations of N-body simulations to be used, for example, for cosmological parameter estimation from surveys of large-scale structure. Our algorithm uses a new method to resample the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Michael D. Schneider , Shaun Cole , Carlos S. Frenk , Istvan Szapudi

The image reconstruction problem of the tomographic imaging technique magnetic particle imaging (MPI) requires the solution of a linear inverse problem. One prerequisite for this task is that the imaging operator that describes the mapping…

Computational Physics · Physics 2019-07-12 Tobias Kluth , Patryk Szwargulski , Tobias Knopp

An efficient parallelization approach to simulate optical properties of ensembles of quantum emitters in realistic electromagnetic environments is considered. It relies on balancing computing load of utilized processors and is built into…

Computational Physics · Physics 2023-02-01 Maxim Sukharev

Quantum-based molecular dynamics (QMD) is a highly accurate and transferable method for material science simulations. However, the time scales and system sizes accessible to QMD are typically limited to picoseconds and a few hundred atoms.…

Learning system dynamics directly from observations is a promising direction in machine learning due to its potential to significantly enhance our ability to understand physical systems. However, the dynamics of many real-world systems are…

Machine Learning · Computer Science 2021-03-23 Karolis Martinkus , Aurelien Lucchi , Nathanaël Perraudin

In this work, we introduce a new algorithm for N-to-M checkpointing in finite element simulations. This new algorithm allows efficient saving/loading of functions representing physical quantities associated with the mesh representing the…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-12-02 David A. Ham , Vaclav Hapla , Matthew G. Knepley , Lawrence Mitchell , Koki Sagiyama

We propose a new fast algorithm for simultaneous recovery of the coil sensitivities and of the magnetization image from incomplete Fourier measurements in parallel MRI. Our approach is based on a parameter model for the coil sensitivities…

Numerical Analysis · Mathematics 2024-10-30 Gerlind Plonka , Yannick Riebe

Upcoming Large Scale Structure surveys aim to achieve an unprecedented level of precision in measuring galaxy clustering. However, accurately modeling these statistics may require theoretical templates that go beyond second-order…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-21 M. Icaza-Lizaola , Yong-Seon Song , Minji Oh , Yi Zheng

We introduce interlaced R2D2 (iR2D2), a DNN series paradigm for scalable image reconstruction from accelerated non-Cartesian k-space acquisitions in MRI with sensitivity map self-calibration. While unrolled DNN architectures provide robust…

Image and Video Processing · Electrical Eng. & Systems 2026-05-05 Shijie Chen , Yiwei Chen , Amir Aghabiglou , Motahare Torki , Chao Tang , Ruud B. van Heeswijk , Yves Wiaux

Sequential Monte Carlo techniques are useful for state estimation in non-linear, non-Gaussian dynamic models. These methods allow us to approximate the joint posterior distribution using sequential importance sampling. In this framework,…

Computation · Statistics 2012-07-09 Mike Klaas , Nando de Freitas , Arnaud Doucet

Obtaining a rigorous and reliable method for linking computer simulations of polymer blends and composites at different length scales of interest is a highly desirable goal in soft matter physics. In this paper a multiscale modeling…

Soft Condensed Matter · Physics 2015-05-19 J. McCarty , M. G. Guenza

Binary embedding of high-dimensional data aims to produce low-dimensional binary codes while preserving discriminative power. State-of-the-art methods often suffer from high computation and storage costs. We present a simple and fast…

Information Theory · Computer Science 2016-01-26 Sung-Hsien Hsieh , Chun-Shien Lu , Soo-Chang Pei

The particle-in-cell approach has proven effective at modeling neutron star and black hole magnetospheres from first principles, but global simulations are plagued with an unrealistically small separation between the scales where…

High Energy Astrophysical Phenomena · Physics 2024-10-09 Adrien Soudais , Benoît Cerutti , Ioannis Contopoulos

Multidimensional scaling is a statistical process that aims to embed high dimensional data into a lower-dimensional space; this process is often used for the purpose of data visualisation. Common multidimensional scaling algorithms tend to…

Machine Learning · Computer Science 2022-02-25 Pierre Lambert , Cyril de Bodt , Michel Verleysen , John Lee
‹ Prev 1 2 3 10 Next ›