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Expectation maximization (EM) algorithm is to find maximum likelihood solution for models having latent variables. A typical example is Gaussian Mixture Model (GMM) which requires Gaussian assumption, however, natural images are highly…

Machine Learning · Computer Science 2018-12-04 Wentian Zhao , Shaojie Wang , Zhihuai Xie , Jing Shi , Chenliang Xu

Medical image reconstruction with pre-trained score-based generative models (SGMs) has advantages over other existing state-of-the-art deep-learned reconstruction methods, including improved resilience to different scanner setups and…

Gaussian boson sampling (GBS) has emerged as a promising quantum computing paradigm, demonstrating its potential in various applications. However, most existing works focus on theoretical aspects or simple tasks, with limited exploration of…

Energy-Based Models (EBMs) present a flexible and appealing way to represent uncertainty. Despite recent advances, training EBMs on high-dimensional data remains a challenging problem as the state-of-the-art approaches are costly, unstable,…

Machine Learning · Computer Science 2021-06-08 Will Grathwohl , Jacob Kelly , Milad Hashemi , Mohammad Norouzi , Kevin Swersky , David Duvenaud

Unwanted nonlinear gamma distortion frequently occurs in a great diversity of images during the procedures of image acquisition, processing, and/or display. And the gamma distortion often varies with capture setup change and luminance…

Image and Video Processing · Electrical Eng. & Systems 2021-12-08 Yong Lee , Shaohua Zhang , Miao Li , Xiaoyu He

Radio observations with Very Long Baseline Interferometry (VLBI) provide the highest resolution in astronomy. Combining earth-bound with space-based telescopes and advancing the observations to mm-wavelengths increases the resolution even…

Astrophysics · Physics 2007-05-23 J. A. Zensus , T. P. Krichbaum , S. Britzen

We propose a multiscale spectral generalized finite element method (MS-GFEM) for discontinuous Galerkin (DG) discretizations. The method builds local approximations on overlapping subdomains as the sum of a local source solution and a…

Numerical Analysis · Mathematics 2026-01-15 Christian Alber , Lukas Holbach

We consider the problem of multifrequency VLBA image synthesis and spectral-index mapping for active galactic nuclei related to the necessity of taking into account the frequency-dependent image shift. We describe our generalized…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-29 Anisa T. Bajkova , Alexander B. Pushkarev

Magnetic resonance imaging (MRI) is a widely used medical imaging modality. However, due to the limitations in hardware, scan time, and throughput, it is often clinically challenging to obtain high-quality MR images. The super-resolution…

Image and Video Processing · Electrical Eng. & Systems 2020-02-20 Qing Lyu , Hongming Shan , Ge Wang

Compact galactic and extragalactic radio sources can be imaged with an unsurpassed angular resolution of a few ten micro-arcseconds, adopting the observing technique of global millimeter VLBI. Here we present the Global Millimeter VLBI…

Astrophysics · Physics 2007-05-23 T. P. Krichbaum , I. Agudo , U. Bach , A. Witzel , J. A. Zensus

We present a maximum likelihood (ML) algorithm that is fast enough to detect gamma-ray transients in real time on low-performance processors often used for space applications. We validate the routine with simulations and find that, relative…

High Energy Astrophysical Phenomena · Physics 2023-08-09 Matthew Kerr , Wade Duvall , Neil Johnson , Richard Woolf , J. Eric Grove , Hannah Kim

We explore the potential of optical intensity interferometry to extract angularly resolved information from supernova explosions, introducing the "expanding ejecta method" (EEM) as a robust alternative to the classical expanding photosphere…

High Energy Astrophysical Phenomena · Physics 2025-04-30 I-Kai Chen , David Dunsky , Ken Van Tilburg , Junwu Huang , Robert V. Wagoner

Multi-spectral imagery is a valuable input signal for Remote Sensing applications, such as land-use and land-cover classification and environmental monitoring. However, generalist Large Multi-modal Models (LMMs) are typically trained on RGB…

Computer Vision and Pattern Recognition · Computer Science 2026-04-24 Dahun Kim , Ganesh Satish Mallya , Anelia Angelova

The wavelet Maximum Entropy on the Mean (wMEM) approach to the MEG inverse problem is revisited and extended to infer brain activity from full space-time data. The resulting dimensionality increase is tackled using a collection of…

Machine Learning · Statistics 2018-07-25 Marie-Christine Roubaud , Jean-Marc Lina , Julie Carrier , B Torrésani

LLM pre-training efficacy increasingly depends on data composition rather than sheer volume. Yet, optimal mixing is hindered by categorization flaws: human taxonomies suffer from ontological misalignment, and Euclidean clustering fails to…

Machine Learning · Computer Science 2026-05-27 Yue Min , Ziyun Qiao , Ruining Chen , Yujun Li

Gas Electron Multiplier (GEM) detectors are crucial for enabling high-resolution X-ray polarisation of astrophysical sources when coupled to custom pixel readout ASIC in Gas Pixel Detectors (GPD), as in the Imaging X-ray Polarimetry…

Instrumentation and Detectors · Physics 2024-02-14 A. Lega , D. Novel , T. Facchinelli , C. Sgro' , L. Baldini , M. Minuti , M. Boscardin , G. Pepponi , R. Iuppa , R. Hall-Wilton , L. Latronico

We establish the theoretical framework for implementing the maximumn entropy on the mean (MEM) method for linear inverse problems in the setting of approximate (data-driven) priors. We prove a.s. convergence for empirical means and further…

Machine Learning · Statistics 2024-12-25 Matthew King-Roskamp , Rustum Choksi , Tim Hoheisel

A flexible maximum-entropy component separation algorithm is presented that accommodates anisotropic noise, incomplete sky-coverage and uncertainties in the spectral parameters of foregrounds. The capabilities of the method are determined…

In this paper, we present a mixed Generalized Multiscale Finite Element Method (GMsFEM) for solving flow in heterogeneous media. Our approach constructs multiscale basis functions following a GMsFEM framework and couples these basis…

Numerical Analysis · Mathematics 2014-06-05 Eric T. Chung , Yalchin Efendiev , Chak Shing Lee

Emulation of the Global (sky-averaged) 21-cm signal with neural networks has been shown to be an essential tool for physical signal modelling. In this paper we present globalemu, a Global 21-cm signal emulator that uses redshift as a…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-18 H. T. J. Bevins , W. J. Handley , A. Fialkov , E. de Lera Acedo , K. Javid
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