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The standard implementation of the Maximum Entropy Method (MEM) follows Bryan and deploys a Singular Value Decomposition (SVD) to limit the dimensionality of the underlying solution space apriori. Here we present arguments based on the…

Computational Physics · Physics 2013-01-08 Alexander Rothkopf

A range of nonlinear image reconstruction procedures based on extremizing the generalized Shannon entropy, Kullback-Leibler cross-entropy and Renyi information measures and proposed by the author in early papers is presented. The…

Astrophysics · Physics 2007-05-23 Anisa T. Bajkova

A maximum entropy method (MEM) is presented for separating the emission due to different foreground components from simulated satellite observations of the cosmic microwave background radiation (CMBR). In particular, the method is applied…

Astrophysics · Physics 2009-10-30 MP Hobson , AW Jones , AN Lasenby , FR Bouchet

The maximum entropy principle (MEP) is one of the most prominent methods to investigate and model complex systems. Despite its popularity, the standard form of the MEP can only generate Boltzmann-Gibbs distributions, which are ill-suited…

Statistical Mechanics · Physics 2022-03-30 Pablo A. Morales , Fernando E. Rosas

In this paper, limitations of the common method measuring intrinsic spatial resolution of the GEM imaging detector are presented. Through theoretical analysis and experimental verification, we have improved the common method to avoid these…

In this work we address the Multiscale Spectral Generalized Finite Element Method (MS-GFEM) developed in [I. Babu\v{s}ka and R. Lipton, Multiscale Modeling and Simulation 9 (2011), pp. 373--406]. We outline the numerical implementation of…

Numerical Analysis · Mathematics 2020-04-22 Ivo Babuska , Robert Lipton , Paul Sinz , Michael Stuebner

We report on an improvement to the implementation of the Maximum Entropy Method (MEM). It amounts to departing from the search space obtained through a singular value decomposition (SVD) of the Kernel. Based on the shape of the SVD basis…

Computational Physics · Physics 2015-03-20 Alexander Rothkopf

Advancements in image generation technologies have raised significant concerns about their potential misuse, such as producing misinformation and deepfakes. Therefore, there is an urgent need for effective methods to detect AI-generated…

Computer Vision and Pattern Recognition · Computer Science 2025-05-22 Lin Yuan , Xiaowan Li , Yan Zhang , Jiawei Zhang , Hongbo Li , Xinbo Gao

We present a new technique for obtaining model fittings to VLBI images of astrophysical jets. The method minimizes a performance function proportional to the sum of the squared difference between the model and observed images. The model…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Anderson Caproni , Hektor Monteiro , Zulema Abraham , Danilo. M. Teixeira , Rafael T. Toffoli

Generalized linear models (GLMs) arise in high-dimensional machine learning, statistics, communications and signal processing. In this paper we analyze GLMs when the data matrix is random, as relevant in problems such as compressed sensing,…

Information Theory · Computer Science 2019-04-01 Jean Barbier , Florent Krzakala , Nicolas Macris , Léo Miolane , Lenka Zdeborová

There remains an important need for the development of image reconstruction methods that can produce diagnostically useful images from undersampled measurements. In magnetic resonance imaging (MRI), for example, such methods can facilitate…

Image and Video Processing · Electrical Eng. & Systems 2021-06-28 Varun A. Kelkar , Sayantan Bhadra , Mark A. Anastasio

The paper addresses a numerical method for solving second order elliptic partial differential equations that describe fields inside heterogeneous media. The scope is general and treats the case of rough coefficients, i.e. coefficients with…

Numerical Analysis · Mathematics 2010-11-30 Ivo Babuska , Robert Lipton

(abridged) Very long baseline interferometry (VLBI) observations at 86$\,$GHz (wavelength, $\lambda = 3\,$mm) reach a resolution of about 50 $\mu$as, probing the collimation and acceleration regions of relativistic outflows in active…

Recent observations by the Event Horizon Telescope (EHT) of supermassive black holes M87* and Sgr A* offer valuable insights into their spacetime properties and astrophysical conditions. Utilizing a library of model images (~2 million for…

High Energy Astrophysical Phenomena · Physics 2024-09-25 A. I. Yfantis , S. Zhao , R. Gold , M. Mościbrodzka , A. E. Broderick

We report resolution enhancement in scanning electron microscopy (SEM) images using a generative adversarial network. We demonstrate the veracity of this deep learning-based super-resolution technique by inferring unresolved features in…

Computer Vision and Pattern Recognition · Computer Science 2019-08-21 Kevin de Haan , Zachary S. Ballard , Yair Rivenson , Yichen Wu , Aydogan Ozcan

We study a parametric estimation problem related to moment condition models. As an alternative to the generalized empirical likelihood (GEL) and the generalized method of moments (GMM), a Bayesian approach to the problem can be adopted,…

Statistics Theory · Mathematics 2012-03-02 Paul Rochet

Ordinary differential equation (ODE)-based diffusion models enable deterministic image synthesis, establishing a reversible mapping suitable for generative steganography. While prevailing methods strictly adhere to a standard normal prior,…

Cryptography and Security · Computer Science 2025-12-16 Yuhua Xu , Wei Sun , Chengpei Tang , Jiaxing Lu , Jingying Zhou , Chen Gu

Obtaining high-resolution images at centimeter-or-longer wavelengths is vital for understanding the physics of jets. We reconstructed images from the M87 22 GHz data observed with the East Asian VLBI Network (EAVN) by using the regularized…

This paper introduces a multiscale maximum entropy (MSME) algorithm for image restoration of the Hard X-ray Modulation Telescope (HXMT), which is a collimated scan X-ray satellite mainly devoted to a sensitive all-sky survey and pointed…

Instrumentation and Methods for Astrophysics · Physics 2016-06-03 Ju Guan , Li-Ming Song , Zhuo-Xi Huo