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Stochastic multi-objective optimization (SMOO) has recently emerged as a powerful framework for addressing machine learning problems with multiple objectives. The bias introduced by the nonlinearity of the subproblem solution mapping…

Optimization and Control · Mathematics 2024-10-10 Linxi Yang , Liping Tang , Jiahao Lv , Yuehong He , Xinmin Yang

The future large adaptive telescopes will trigger new constraints for the calibration of Adaptive Optics (AO) systems equipped with pre-focal Deformable Mirrors (DM). The image of the DM actuators grid as seen by the Wave-Front Sensor (WFS)…

Instrumentation and Methods for Astrophysics · Physics 2021-05-26 C. T. Heritier , T. Fusco , S. Oberti , B. Neichel , S. Esposito , P. -Y. Madec

Stochastic descent methods (of the gradient and mirror varieties) have become increasingly popular in optimization. In fact, it is now widely recognized that the success of deep learning is not only due to the special deep architecture of…

Machine Learning · Computer Science 2019-01-21 Navid Azizan , Babak Hassibi

In this paper we propose a blind deconvolution method which applies to data perturbed by Poisson noise. The objective function is a generalized Kullback-Leibler divergence, depending on both the unknown object and unknown point spread…

Instrumentation and Methods for Astrophysics · Physics 2013-11-25 M. Prato , A. La Camera , S. Bonettini , M. Bertero

Stochastic Gradient Descent (SGD) is an out-of-equilibrium algorithm used extensively to train artificial neural networks. However very little is known on to what extent SGD is crucial for to the success of this technology and, in…

Machine Learning · Computer Science 2023-12-19 Persia Jana Kamali , Pierfrancesco Urbani

We propose a projected semi-stochastic gradient descent method with mini-batch for improving both the theoretical complexity and practical performance of the general stochastic gradient descent method (SGD). We are able to prove linear…

Machine Learning · Computer Science 2017-05-08 Jie Liu , Martin Takac

Stochastic Gradient Descent (SGD) is a popular algorithm that can achieve state-of-the-art performance on a variety of machine learning tasks. Several researchers have recently proposed schemes to parallelize SGD, but all require…

Optimization and Control · Mathematics 2011-11-14 Feng Niu , Benjamin Recht , Christopher Re , Stephen J. Wright

In this paper, we present a new stochastic algorithm, namely the stochastic block mirror descent (SBMD) method for solving large-scale nonsmooth and stochastic optimization problems. The basic idea of this algorithm is to incorporate the…

Optimization and Control · Mathematics 2013-09-10 Cong D. Dang , Guanghui Lan

The search for exoplanets is pushing adaptive optics systems on ground-based telescopes to their limits. One of the major limitations at small angular separations, exactly where exoplanets are predicted to be, is the servo-lag of the…

Stochastic gradient methods (SGMs) have been widely used for solving stochastic optimization problems. A majority of existing works assume no constraints or easy-to-project constraints. In this paper, we consider convex stochastic…

Optimization and Control · Mathematics 2022-01-03 Yonggui Yan , Yangyang Xu

Image restoration in astronomy has been considered a vital step in many ground-based observational programs that often suffer from sub-optimal seeing due to atmospheric turbulence, distortion of stellar shapes due to instrumental…

Instrumentation and Methods for Astrophysics · Physics 2023-09-14 Yash Gondhalekar , Margarita Safonova , Snehanshu Saha

Recent progress in quantum technologies with ultracold atoms has been propelled by spatially fine-tuned control of lasers and diffraction-limited imaging. The state-of-the-art precision of optical alignment to achieve this fine-tuning is…

Quantum Gases · Physics 2024-01-03 Bharath Hebbe Madhusudhana , Karatzyna Krzyzanowska , Malcolm Boshier

With the commissioning of the refurbished adaptive secondary mirror (ASM) for the 6.5-meter MMT Observatory under way, special consideration had to be made to properly calibrate the mirror response functions to generate an interaction…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 Jacob Taylor , Robin Swanson , Parker Levesque , Masen Lamb , Amali Vaz , Manny Montoya , Andrew Gardner , Katie M. Morzinski , Suresh Sivanandam

Stochastic Gradient Langevin Dynamics infuses isotropic gradient noise to SGD to help navigate pathological curvature in the loss landscape for deep networks. Isotropic nature of the noise leads to poor scaling, and adaptive methods based…

Machine Learning · Computer Science 2019-06-13 Chandrasekaran Anirudh Bhardwaj

Context. Most popular algorithms in use to remove the effects of a telescope's point spread function (PSF) in radio astronomy are variants of the CLEAN algorithm. Most of these algorithms model the sky brightness using the delta-function…

Instrumentation and Methods for Astrophysics · Physics 2017-12-18 L. Zhang , S. Bhatnagar , U. Rau , M. Zhang

While stochastic gradient descent (SGD) is still the \emph{de facto} algorithm in deep learning, adaptive methods like Clipped SGD/Adam have been observed to outperform SGD across important tasks, such as attention models. The settings…

Optimization and Control · Mathematics 2020-10-26 Jingzhao Zhang , Sai Praneeth Karimireddy , Andreas Veit , Seungyeon Kim , Sashank J Reddi , Sanjiv Kumar , Suvrit Sra

Stochastic gradient descent (SGD) is the main approach for training deep networks: it moves towards the optimum of the cost function by iteratively updating the parameters of a model in the direction of the gradient of the loss evaluated on…

Machine Learning · Computer Science 2021-03-30 Loris Nanni , Gianluca Maguolo , Alessandra Lumini

Lagrangian particle methods based on detailed atomic and molecular models are powerful computational tools for studying the dynamics of microscale and nanoscale systems. However, the maximum time step is limited by the smallest oscillation…

Computational Physics · Physics 2019-06-26 Ansel L. Blumers , Zhen Li , George Em Karniadakis

This paper explores chaos control in the Sprott circuit by leveraging Stochastic Gradient Descent (SGD) to calibrate Pyragas delayed feedback control. Using a third-order nonlinear differential equation, we model the circuit and aim to…

Chaotic Dynamics · Physics 2025-08-08 Adib Kabir , Onil Morshed , Oishi Kabir , Juthi Hira , Caitlin Hult

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill