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Large-scale structure (LSS) analysis in galaxy surveys is a powerful cosmological probe but is limited by tracer bias, which can obscure underlying information and weaken parameter constraints. Existing methods either model bias or restrict…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-01 Zhujun Jiang , Xiaolin Luo , Wenying Du , Zhiwei Min , Fenfen Yin , Longlong Feng , Jiacheng Ding , Le Zhang , Xiao-Dong Li

Wavefront shaping is increasingly being used in modern microscopy to obtain distortion-free, high-resolution images deep inside inhomogeneous media. Wavefront shaping methods typically rely on the presence of a 'guidestar' in order to find…

Multimodal medical images play a crucial role in the precise and comprehensive clinical diagnosis. Diffusion model is a powerful strategy to synthesize the required medical images. However, existing approaches still suffer from the problem…

Computer Vision and Pattern Recognition · Computer Science 2025-05-28 Jiahua Xu , Dawei Zhou , Lei Hu , Zaiyi Liu , Nannan Wang , Xinbo Gao

Masked (or absorbing) diffusion is actively explored as an alternative to autoregressive models for generative modeling of discrete data. However, existing work in this area has been hindered by unnecessarily complex model formulations and…

Machine Learning · Computer Science 2025-01-17 Jiaxin Shi , Kehang Han , Zhe Wang , Arnaud Doucet , Michalis K. Titsias

We present a data-driven technique to analyze multifrequency images from upcoming cosmological surveys mapping large sky area. Using full information from the data at the two-point level, our method can simultaneously constrain the…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-01 Yun-Ting Cheng , Benjamin D. Wandelt , Tzu-Ching Chang , Olivier Dore

In this paper, we propose a solution for a fundamental problem in computational harmonic analysis, namely, the construction of a multiresolution analysis with directional components. We will do so by constructing subdivision schemes which…

Numerical Analysis · Mathematics 2007-10-16 Gitta Kutyniok , Tomas Sauer

Probabilistic Diffusion Models (PDMs) have recently emerged as a very promising class of generative models, achieving high performance in natural image generation. However, their performance relative to non-natural images, like radar-based…

Computer Vision and Pattern Recognition · Computer Science 2023-11-29 Alexandre Tuel , Thomas Kerdreux , Claudia Hulbert , Bertrand Rouet-Leduc

Diffusion models have become the dominant tool for high-fidelity image and video generation, yet are critically bottlenecked by their inference speed due to the numerous iterative passes of Diffusion Transformers. To reduce the exhaustive…

Computer Vision and Pattern Recognition · Computer Science 2026-03-03 Jiaqi Han , Juntong Shi , Puheng Li , Haotian Ye , Qiushan Guo , Stefano Ermon

We present a method for subtracting point sources from interferometric radio images via forward modeling of the instrument response and involving an algebraic nonlinear minimization. The method is applied to simulated maps of the Murchison…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Bernardi , D. A. Mitchell , S. M. Ord , L. J. Greenhill , B. Pindor , R. B. Wayth , J. S. B. Wyithe

In radio interferometry, observed visibilities are intrinsically sampled at some interval in time and frequency. Modern interferometers are capable of producing data at very high time and frequency resolution; practical limits on storage…

Instrumentation and Methods for Astrophysics · Physics 2016-07-15 M. T. Atemkeng , O. M. Smirnov , C. Tasse , G. Foster , J. Jonas

Conventional approaches to cosmology inference from galaxy redshift surveys are based on n-point functions, which are under rigorous perturbative control on sufficiently large scales. Here, we present an alternative approach, which employs…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 Fabian Schmidt , Franz Elsner , Jens Jasche , Nhat Minh Nguyen , Guilhem Lavaux

A simple Gaussian size deconvolution method is routinely used to remove the blur of observed images caused by insufficient angular resolutions of existing telescopes, thereby to estimate the physical sizes of extracted sources and…

Instrumentation and Methods for Astrophysics · Physics 2023-07-26 Alexander Men'shchikov

Radio propagation modeling and prediction is fundamental for modern cellular network planning and optimization. Conventional radio propagation models fall into two categories. Empirical models, based on coarse statistics, are simple and…

Information Theory · Computer Science 2021-10-06 Xin Zhang , Xiujun Shu , Bingwen Zhang , Jie Ren , Lizhou Zhou , Xin Chen

Interstellar scintillation can be used to probe transverse sizes of radio sources on scales inaccessible to the nominal resolution of any terrestrial telescope, e.g. $\lesssim 10^{-6}$ arc sec. Methodology is presented that exploits this…

Astrophysics · Physics 2007-05-23 J. M. Cordes

A wavelet-based method for compression of three-dimensional simulation data is presented and its software framework is described. It uses wavelet decomposition and subsequent range coding with quantization suitable for floating-point data.…

Computational Physics · Physics 2022-01-06 Dmitry Kolomenskiy , Ryo Onishi , Hitoshi Uehara

Model fitting is frequently used to determine the shape of galaxies and the point spread function, for examples, in weak lensing analyses or morphology studies aiming at probing the evolution of galaxies. However, the number of parameters…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-03 Guoliang Li , Bo Xin , Wei Cui

Currently, applying diffusion models in pixel space of high resolution images is difficult. Instead, existing approaches focus on diffusion in lower dimensional spaces (latent diffusion), or have multiple super-resolution levels of…

Computer Vision and Pattern Recognition · Computer Science 2023-12-13 Emiel Hoogeboom , Jonathan Heek , Tim Salimans

Diffusion models for continuous data gained widespread adoption owing to their high quality generation and control mechanisms. However, controllable diffusion on discrete data faces challenges given that continuous guidance methods do not…

Deep image registration has demonstrated exceptional accuracy and fast inference. Recent advances have adopted either multiple cascades or pyramid architectures to estimate dense deformation fields in a coarse-to-fine manner. However, due…

Computer Vision and Pattern Recognition · Computer Science 2024-07-19 Xinxing Cheng , Xi Jia , Wenqi Lu , Qiufu Li , Linlin Shen , Alexander Krull , Jinming Duan

We propose a machine-learning-based technique to determine the number density of radio sources as a function of their flux density, for use in next-generation radio surveys. The method uses a convolutional neural network trained on…

Instrumentation and Methods for Astrophysics · Physics 2024-01-17 Elisa Todarello , Andre Scaffidi , Marco Regis , Marco Taoso