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相关论文: Stochastic Calibration of Radio Interferometers

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Rolling forecasts have been almost overlooked in the renewable energy storage literature. In this paper, we provide a new approach for handling uncertainty not just in the accuracy of a forecast, but in the evolution of forecasts over time.…

最优化与控制 · 数学 2022-04-18 Saeed Ghadimi , Warren B. Powell

Calibration is a common experimental physics problem, whose goal is to infer the value and uncertainty of an unobservable quantity Z given a measured quantity X. Additionally, one would like to quantify the extent to which X and Z are…

高能物理 - 唯象学 · 物理学 2023-09-26 Rikab Gambhir , Benjamin Nachman , Jesse Thaler

Calibration data are often obtained by observing several well-understood objects simultaneously with multiple instruments, such as satellites for measuring astronomical sources. Analyzing such data and obtaining proper concordance among the…

应用统计 · 统计学 2018-09-28 Yang Chen , Xiao-Li Meng , Xufei Wang , David A. van Dyk , Herman L. Marshall , Vinay L. Kashyap

Calibration measures quantify how much a forecaster's predictions violates calibration, which requires that forecasts are unbiased conditioning on the forecasted probabilities. Two important desiderata for a calibration measure are its…

机器学习 · 计算机科学 2025-03-05 Mingda Qiao , Eric Zhao

The wavelength calibration of spectrographs is an essential but challenging task in many disciplines. Calibration is traditionally accomplished by imaging the spectrum of a light source containing features that are known to appear at…

天体物理仪器与方法 · 物理学 2018-04-04 Neil Thomas

Baseline calibration of a stellar interferometer is a prerequisite to data reduction of astrometric operations. This technique of astrometry is triangulation of star positions. Since angles are deduced from the baseline and delay side of…

天体物理仪器与方法 · 物理学 2009-06-16 Richard J. Mathar

Reservoir computing is a form of machine learning that utilizes nonlinear dynamical systems to perform complex tasks in a cost-effective manner when compared to typical neural networks. Many recent advancements in reservoir computing, in…

机器学习 · 计算机科学 2025-04-03 Peter J. Ehlers , Hendra I. Nurdin , Daniel Soh

A selection of statistically stable (robust) algorithms for data variance calculating has been made. Their properties have been analyzed via computer simulation. These algorithms would be useful if adopted in radio astronomy observations in…

天体物理仪器与方法 · 物理学 2015-03-17 P. A. Fridman

Several cosmological measurements have attained significant levels of maturity and accuracy over the last decade. Continuing this trend, future observations promise measurements of the statistics of the cosmic mass distribution at an…

天体物理学 · 物理学 2008-11-26 Salman Habib , Katrin Heitmann , David Higdon , Charles Nakhleh , Brian Williams

The ionosphere is the main driver of a series of systematic effects that limit our ability to explore the low frequency (<1 GHz) sky with radio interferometers. Its effects become increasingly important towards lower frequencies and are…

天体物理仪器与方法 · 物理学 2018-08-08 F. de Gasperin , M. Mevius , D. A. Rafferty , H. T. Intema , R. A. Fallows

We study stochastic optimization of nonconvex loss functions, which are typical objectives for training neural networks. We propose stochastic approximation algorithms which optimize a series of regularized, nonlinearized losses on large…

机器学习 · 计算机科学 2019-03-12 Weiran Wang , Nathan Srebro

Next generation radio observatories such as the MWA, LWA, LOFAR, CARMA and SKA provide a number of challenges for interferometric data analysis. These challenges include heterogeneous arrays, direction-dependent instrumental gain, and…

天体物理学 · 物理学 2015-05-13 Miguel F. Morales , Michael Matejek

Well-calibrated spectropolarimetry studies at resolutions of $R>$10,000 with signal-to-noise ratios (SNRs) better than 0.01\% across individual line profiles, are becoming common with larger aperture telescopes. Spectropolarimetric studies…

天体物理仪器与方法 · 物理学 2015-06-24 David Harrington , J. R. Kuhn , Rebecca Nevin

New generation of radio interferometers are envisaged to produce high quality, high dynamic range Stokes images of the observed sky from the corresponding under-sampled Fourier domain measurements. In practice, these measurements are…

天体物理仪器与方法 · 物理学 2020-01-08 Jasleen Birdi , Audrey Repetti , Yves Wiaux

Existing approaches to resource allocation for nowadays stochastic networks are challenged to meet fast convergence and tolerable delay requirements. The present paper leverages online learning advances to facilitate stochastic resource…

最优化与控制 · 数学 2017-05-24 Tianyi Chen , Aryan Mokhtari , Xin Wang , Alejandro Ribeiro , Georgios B. Giannakis

In the context of computer models, calibration is the process of estimating unknown simulator parameters from observational data. Calibration is variously referred to as model fitting, parameter estimation/inference, an inverse problem, and…

统计方法学 · 统计学 2023-10-16 Richard D. Wilkinson , Christopher W. Lanyon

The ambitious scientific goals of SKA require a matching capability for calibration of instrumental and atmospheric propagation contributions as functions of time, frequency and position. The development of novel calibration algorithms to…

天体物理仪器与方法 · 物理学 2022-02-01 María J. Rioja , Richard Dodson

Accurate uncertainty estimates are important in sequential model-based decision-making tasks such as Bayesian optimization. However, these estimates can be imperfect if the data violates assumptions made by the model (e.g., Gaussianity).…

机器学习 · 计算机科学 2024-06-27 Shachi Deshpande , Charles Marx , Volodymyr Kuleshov

This paper introduces an amendment to radio interferometric calibration of sources below the noise level. The main idea is to employ the information of the stronger sources' measured signals as a plug-in criterion to solve for the weaker…

天体物理仪器与方法 · 物理学 2016-11-15 Sanaz Kazemi , Sarod Yatawatta , Saleem Zaroubi

The complexity and accuracy of current and future precision cosmology observational campaigns has made it essential to develop an efficient technique for directly combining simulation and observational datasets to determine cosmological and…

天体物理学 · 物理学 2009-11-11 Katrin Heitmann , David Higdon , Charles Nakhleh , Salman Habib