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The inverse-free extreme learning machine (ELM) algorithm proposed in [4] was based on an inverse-free algorithm to compute the regularized pseudo-inverse, which was deduced from an inverse-free recursive algorithm to update the inverse of…

Machine Learning · Computer Science 2019-11-13 Hufei Zhu , Chenghao Wei

The tracking method based on the extreme learning machine (ELM) is efficient and effective. ELM randomly generates input weights and biases in the hidden layer, and then calculates and computes the output weights by reducing the iterative…

Machine Learning · Computer Science 2018-07-27 Jing Zhang , Huibing Wang , Yonggong Ren

Maximum Entropy is an image reconstruction method conceived to image a sparsely occupied field of view and therefore particularly appropriate to achieve super-resolution effects. Although widely used in image deconvolution, this method has…

Solar and Stellar Astrophysics · Physics 2020-05-13 Paolo Massa , Richard Schwartz , A Kim Tolbert , Anna Maria Massone , Brian R Dennis , Michele Piana , Federico Benvenuto

X-ray and EUV observations are an important diagnostic of various plasma parameters of the solar atmosphere during solar flares. Soft X-ray and EUV observations often show coronal sources near the top of flaring loops, while hard X-ray…

Solar and Stellar Astrophysics · Physics 2015-06-11 Marina Battaglia , Eduard P. Kontar

Stochastic Maximum Likelihood (SML) is a popular direction of arrival (DOA) estimation technique in array signal processing. It is a parametric method that jointly estimates signal and instrument noise by maximum likelihood, achieving…

Applications · Statistics 2021-02-04 Matthieu Simeoni , Paul Hurley

Accurate characterization of atmospheric optical turbulence is essential for evaluating astronomical sites and optimizing adaptive optics systems. The Multistar Turbulence Monitor (MTM) infers the vertical distribution of the…

Instrumentation and Methods for Astrophysics · Physics 2026-05-08 Weisen Huang , Bin Ma , Tengfei Song , Paul Hickson , Zhaohui Shang , Xuefei Zhang , Mingyu Zhao , Qing Zhou

Estimators derived from a divergence criterion such as $\varphi-$divergences are generally more robust than the maximum likelihood ones. We are interested in particular in the so-called MD$\varphi$DE, an estimator built using a dual…

Computation · Statistics 2016-06-14 Diaa Al Mohamad , Michel Broniatowski

X-Ray and Ultraviolet (UV) observations of the outer solar atmosphere have been used for many decades to measure the fundamental parameters of the solar plasma. This review focuses on the optically thin emission from the solar atmosphere,…

Solar and Stellar Astrophysics · Physics 2018-09-06 Giulio Del Zanna , Helen E. Mason

We propose an adaptive regularization scheme in a variational framework where a convex composite energy functional is optimized. We consider a number of imaging problems including denoising, segmentation and motion estimation, which are…

Computer Vision and Pattern Recognition · Computer Science 2017-03-01 Byung-Woo Hong , Ja-Keoung Koo , Hendrik Dirks , Martin Burger

Unpredictability of renewable energy sources coupled with the complexity of those methods used for various purposes in this area calls for the development of robust methods such as DL models within the renewable energy domain. Given the…

Machine Learning · Computer Science 2025-05-07 Lutfu Sua , Haibo Wang , Jun Huang

We compare the ability of 11 Differential Emission Measure (DEM) forward-fitting and inversion methods to constrain the properties of active regions and solar flares by simulating synthetic data using the instrumental response functions of…

Solar and Stellar Astrophysics · Physics 2016-04-13 M. J. Aschwanden , P. Boerner , A. Caspi , J. M. McTiernan , D. Ryan , H. P. Warren

Determining the temperature distribution of coronal plasmas can provide stringent constraints on coronal heating. Current observations with the Extreme ultraviolet Imaging Spectrograph onboard Hinode and the Atmospheric Imaging Assembly…

Solar and Stellar Astrophysics · Physics 2015-06-11 Paola Testa , Bart De Pontieu , Juan Martinez-Sykora , Viggo Hansteen , Mats Carlsson

Many imaging problems require solving an inverse problem that is ill-conditioned or ill-posed. Imaging methods typically address this difficulty by regularising the estimation problem to make it well-posed. This often requires setting the…

Methodology · Statistics 2020-08-17 Ana F. Vidal , Valentin De Bortoli , Marcelo Pereyra , Alain Durmus

Deconvolving COMPTEL gamma-ray data into images presents a major methodological challenge. We developed a new algorithm called Multiresolution Regularized Expectation Maximization (MREM), which explicitly accounts for spatial correlations…

We present a new iterative rotation inversion technique based on the Simultaneous Algebraic Reconstruction Technique developed for image reconstruction. We describe in detail our algorithmic implementation and compare it to the classical…

Solar and Stellar Astrophysics · Physics 2024-06-17 Sylvain G. Korzennik , Antonio Eff-Darwich

The $\textrm{HRI}_\textrm{EUV}$ telescope was calibrated on ground at the Physikalisch-Technische Bundesanstalt (PTB), Germany's national metrology institute, using the Metrology Light Source (MLS) synchrotron in April 2017 during the…

One of the objectives of the NASA LWS Institute on Nowcasting of Atmospheric Drag for LEO Spacecraft was to investigate whether and how to increase the accuracy of atmospheric drag models by improving the quality of the solar forcing…

Solar and Stellar Astrophysics · Physics 2018-07-04 A. Vourlidas , S. Bruinsma

Electroluminescence (EL) imaging is a powerful and established technique for assessing the quality of photovoltaic (PV) modules, which consist of many electrically connected solar cells arranged in a grid. The analysis of imperfect…

Computer Vision and Pattern Recognition · Computer Science 2020-09-01 Evgenii Sovetkin , Ansgar Steland

Randomized neural networks (NNs) are an interesting alternative to conventional NNs that are more used for data modeling. The random vector functional-link (RVFL) network is an established and theoretically well-grounded randomized learning…

Computation · Statistics 2018-04-24 Hien D. Nguyen , Dianhui Wang , Geoffrey J. McLachlan

During the inversion of discrete linear systems noise in data can be amplified and result in meaningless solutions. To combat this effect, characteristics of solutions that are considered desirable are mathematically implemented during…

Numerical Analysis · Mathematics 2023-02-07 Michael J. Byrne , Rosemary A. Renaut