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Related papers: Iterative initial condition reconstruction

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In the reconstruction process of unknown multiple scattering objects in inverse medium scattering problems, the first important step is to effectively locate some approximate domains that contain all inhomogeneous media. Without such an…

Numerical Analysis · Mathematics 2015-06-12 Keji Liu , Jun Zou

The cosmic structure formed from Baryon Acoustic Oscillations (BAO) in the early universe is imprinted in the galaxy distribution observable in large scale surveys, and is used as a standard ruler in contemporary cosmology. BAO are…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-07 Z. Brown , G. Mishtaku , R. Demina , Y. Liu , C. Popik

We address the inverse problem of cosmic large-scale structure reconstruction from a Bayesian perspective. For a linear data model, a number of known and novel reconstruction schemes, which differ in terms of the underlying signal prior,…

Astrophysics · Physics 2009-11-06 F. S. Kitaura , T. A. Ensslin

We consider the inverse problem of quantitative reconstruction of properties (e.g., bulk modulus, density) of visco-acoustic materials based on measurements of responding waves after stimulation of the medium. Numerical reconstruction is…

Analysis of PDEs · Mathematics 2022-09-20 Florian Faucher , Otmar Scherzer

We discuss a new algorithm to generate multi-scale initial conditions with multiple levels of refinements for cosmological "zoom-in" simulations. The method uses an adaptive convolution of Gaussian white noise with a real space transfer…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Oliver Hahn , Tom Abel

Our research objective in this paper is to reconstruct an initial linear density field, which follows the multivariate Gaussian distribution with variances given by the linear power spectrum of the current CDM model and evolves through…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Huiyuan Wang , H. J. Mo , Xiaohu Yang , Frank C. van den Bosch

We develop and apply a new framework for reconstructing the ionization history during the epoch of recombination with combinations of cosmic microwave background (CMB), baryon acoustic oscillation (BAO) and supernova data. We find a wide…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Gabriel P. Lynch , Lloyd Knox , Jens Chluba

Low-dose tomography is highly preferred in medical procedures for its reduced radiation risk when compared to standard-dose Computed Tomography (CT). However, the lower the intensity of X-rays, the higher the acquisition noise and hence the…

Image and Video Processing · Electrical Eng. & Systems 2019-12-24 Preeti Gopal , Sharat Chandran , Imants Svalbe , Ajit Rajwade

Reconstructing the initial density field of the Universe from the late-time matter distribution is a nontrivial task with implications for understanding structure formation in cosmology, offering insights into early Universe conditions.…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-26 Koichiro Nakashima , Kiyotomo Ichiki , Atsushi J. Nishizawa , Kenji Hasegawa

Intensity mapping of 21-cm line by several radio telescope experiments will probe the large-scale structure of the Universe in the post-reionization epoch. It requires a theoretical framework of neutral hydrogen (HI) clustering, such as…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-18 Rika Ando , Atsushi J Nishizawa , Shimizu Ikkoh , Kentaro Nagamine

Reconstructing the density fluctuations in the early Universe that evolved into the distribution of galaxies we see today is a challenge of modern cosmology [ref.]. An accurate reconstruction would allow us to test cosmological models by…

Astrophysics · Physics 2015-06-24 Uriel Frisch , Sabino Matarrese , Roya Mohayaee , Andrei Sobolevski

Recently, research on denoising diffusion models has expanded its application to the field of image restoration. Traditional diffusion-based image restoration methods utilize degraded images as conditional input to effectively guide the…

Computer Vision and Pattern Recognition · Computer Science 2024-10-25 Zhenning Shi , Haoshuai Zheng , Chen Xu , Changsheng Dong , Bin Pan , Xueshuo Xie , Along He , Tao Li , Huazhu Fu

The physical scale corresponding to baryon acoustic oscillations (BAO), the size of the sound horizon at recombination, is precisely determined by CMB experiments. Measuring the apparent size of the BAO scale imprinted in the clustering of…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-29 Ivana Babić , Fabian Schmidt , Beatriz Tucci

We present a fully probabilistic, physical model of the non-linearly evolved density field, as probed by realistic galaxy surveys. Our model is valid in the linear and mildly non-linear regimes and uses second order Lagrangian perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jens Jasche , Benjamin D. Wandelt

The algorithm ZTRACE of Monaco & Efstathiou (1999) is applied to the IRAS PSCz catalogue to reconstruct the initial conditions of our local Universe with a resolution down to ~5 Mpc/h. The 1-point PDF of the reconstructed initial conditions…

Common problem in signal processing is reconstruction of the missing signal samples. Missing samples can occur by intentionally omitting signal coefficients to reduce memory requirements, or to speed up the transmission process. Also, noisy…

Information Theory · Computer Science 2015-03-02 Slavoljub Jokić , Ljindita Niković , Jelena Kadović

Given a set of samples, a few of them being possibly saturated, we propose an efficient algorithm in order to cancel saturation while reconstructing band-limited signals. Our method satisfies a minimum-loss constraint and relies on…

Signal Processing · Electrical Eng. & Systems 2018-09-20 Kyong Hwan Jin , Gain Kim , Yusuf Leblebici , Jong Chul Ye , Michael Unser

The formalism of Wiener filtering is developed here for the purpose of reconstructing the large scale structure of the universe from noisy, sparse and incomplete data. The method is based on a linear minimum variance solution, given data…

Astrophysics · Physics 2009-10-22 S. Zaroubi , Y. Hoffman , K. B. Fisher , O. Lahav

Recovering the digital input of a time-discrete linear system from its (noisy) output is a significant challenge in the fields of data transmission, deconvolution, channel equalization, and inverse modeling. A variety of algorithms have…

Optimization and Control · Mathematics 2020-12-03 Sophie M. Fosson

Ultrasound-modulated optical tomography is an emerging biomedical imaging modality which uses the spatially localised acoustically-driven modulation of coherent light as a probe of the structure and optical properties of biological tissues.…

Medical Physics · Physics 2016-03-22 Samuel Powell , Simon R. Arridge , Terence S. Leung
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