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Bias correction is a common pre-processing step applied to climate model data before it is used for further analysis. This article introduces an efficient adaptation of a well-established bias-correction method - quantile mapping - for…

Applications · Statistics 2024-06-03 Maggie D. Bailey , Douglas W. Nychka , Manajit Sengupta , Soutir Bandyopadhyay

Recently, the National Solar Observatory (NSO) Solar-atmosphere Pipeline Working Group has undertaken the production of synoptic maps from Helioseismic and Magnetic Imager (HMI) magnetograms. A set of maps has been processed spanning the…

Instrumentation and Methods for Astrophysics · Physics 2016-05-12 Anna L. H. Hughes , Luca Bertello , Andrew R. Marble , Niles A. Oien , Gordon Petrie , Alexei A. Pevtsov

In this paper, we consider incorporating data associated with the sun's north and south polar field strengths to improve solar flare prediction performance using machine learning models. When used to supplement local data from active…

Solar and Stellar Astrophysics · Physics 2022-12-06 Mehmet Aktukmak , Zeyu Sun , Monica Bobra , Tamas Gombosi , Ward B. Manchester , Yang Chen , Alfred Hero

We investigate the cross-calibration of the Hinode/SOT-SP and SDO/HMI instrument meta-data, specifically the correspondence of the scaling and pointing information. Accurate calibration of these datasets gives the correspondence needed by…

When scientometric indicators are used to compare research units active in different scientific fields, there often is a need to make corrections for differences between fields, for instance differences in publication, collaboration, and…

Digital Libraries · Computer Science 2018-01-31 Ludo Waltman , Nees Jan van Eck

We describe the coordinate systems of two streams of HMI active region vector data. A distinction is made between (a) the 2D grid on which the field vector is measured (or sampled), and (b) the 3D coordinate established at each grid point,…

Solar and Stellar Astrophysics · Physics 2022-09-07 Xudong Sun

While the polar system may lack the universal familiarity of its Cartesian counterpart, it remains indispensable for certain tasks. Summary polar diagrams, such as Taylor and mutual information diagrams, address tasks like discovering…

Human-Computer Interaction · Computer Science 2026-04-21 Aleksandar Anžel , Zewen Yang , Georges Hattab

The Helioseismic and Magnetic Imager (HMI) has just started producing data that will help determine what the sources and mechanisms of variability in the Sun's interior are. The instrument measures the Doppler shift and the polarization of…

Solar and Stellar Astrophysics · Physics 2010-12-20 Rebecca Centeno , Steve Tomczyk , Juan Manuel Borrero , Sebastien Couvidat , Keiji Hayashi , Todd Hoeksema , Yang Liu , Jesper Schou

This article presents a publicly available, multimodal, tiered magnetic polarity inversion lines (MPILs) dataset extracted from the Solar Dynamics Observatory's (SDO) Helioseismic and Magnetic Imager (HMI) Active Region Patches (SDO/HMI…

Solar and Stellar Astrophysics · Physics 2025-08-26 Ziba Khani , Anli Ji , Manolis K. Georgoulis , Berkay Aydin

The polar magnetic field of the Sun is a manifestation of certain aspects of the dynamo process and is a good precursor for predicting a sunspot cycle before its onset. Although actual synoptic measurements of this field exist only from the…

Solar and Stellar Astrophysics · Physics 2019-01-30 Arnab Rai Choudhuri

This mini-review provides a perspective on recent progress and emerging directions aimed at utilizing and controlling in-plane optical polarization, highlighting key application spaces where in-plane near-field tip responses have enabled…

Mesoscale and Nanoscale Physics · Physics 2015-12-09 P. James Schuck , Wei Bao , Nicholas J. Borys

The Gemini Planet Imager (GPI) has been designed for the direct detection and characterization of exoplanets and circumstellar disks. GPI is equipped with a dual channel polarimetry mode designed to take advantage of the inherently…

Context. Polarimetric imaging is one of the most effective techniques for high-contrast imaging and characterization of protoplanetary disks, and has the potential to be instrumental in characterizing exoplanets. VLT/SPHERE contains the…

We investigate the orientation of the photospheric magnetic fields in the solar polar region using observations from the Helioseismic and Magnetic Imager (HMI). Inside small patches of significant polarization, the inferred magnetic field…

Solar and Stellar Astrophysics · Physics 2021-06-04 Xudong Sun , Yang Liu , Ivan Milić , Ana Belén Griñón Marín

The distribution and evolution of the magnetic field at the solar poles through a solar cycle is an important parameter in understanding the solar dynamo. The accurate observations of the polar magnetic flux is very challenging from the…

Solar and Stellar Astrophysics · Physics 2024-07-26 Sanjay Gosain , Han Uitenbroek

Synthetic aperture radar (SAR) images are often blurred by phase perturbations induced by uncompensated sensor motion and /or unknown propagation effects caused by turbulent media. To get refocused images, autofocus proves to be useful…

Instrumentation and Methods for Astrophysics · Physics 2015-03-03 Xinhua Mao , Daiyin Zhu , Zhaoda Zhu

We present a simple method to enable processing of Spotlight Synthetic Aperture Radar (SAR) imagery distributed in Polar Format (PFA) using standard Range-Doppler (RDA) geometry algorithms. Our approach is applicable to PFA SAR images…

Image and Video Processing · Electrical Eng. & Systems 2025-03-12 Piyush S. Agram

The analogue of polar coordinates in the Euclidean space, a polar decomposition in a metric space, if well-defined, can be very useful in dealing with integrals with respect to a sufficiently regular measure. In this note we handle the…

Functional Analysis · Mathematics 2023-09-06 Zhirayr Avetisyan , Michael Ruzhansky

Characterizing the intensity, phase, and polarization of engineered light is fundamental to understanding and applying metasurfaces. However, existing characterization frameworks are hindered by several limitations, most notably their…

Optics · Physics 2026-02-20 Xinjie Sun , Xin Liu , Zixin Cai , Yanghui Li , Xu Liu , Xiang Hao

In coding theory, an error-correcting code can be encoded either systematically or non-systematically. In a systematic encode, the input data is embedded in the encoded output. Conversely, in a non-systematic code, the output does not…

Information Theory · Computer Science 2023-08-17 Mengfan Zheng
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