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Hyperspectral remote sensing images (HSIs) usually have high spectral resolution and low spatial resolution. Conversely, multispectral images (MSIs) usually have low spectral and high spatial resolutions. The problem of inferring images…

Computer Vision and Pattern Recognition · Computer Science 2015-06-23 Miguel Simões , José Bioucas-Dias , Luis B. Almeida , Jocelyn Chanussot

GenASiS (General Astrophysical Simulation System) is a new code being developed initially and primarily, though by no means exclusively, for the simulation of core-collapse supernovae on the world's leading capability supercomputers. This…

Instrumentation and Methods for Astrophysics · Physics 2015-07-09 Christian Y. Cardall , Reuben D. Budiardja , Eirik Endeve , Anthony Mezzacappa

Integrated sensing and communication (ISAC) has attracted much attention as a promising approach to alleviate spectrum congestion. However, traditional ISAC systems rely on phased arrays to provide high spatial diversity, where enormous…

Signal Processing · Electrical Eng. & Systems 2023-03-27 Haobo Zhang , Hongliang Zhang , Boya Di , Lingyang Song

High-level synthesis (HLS) is a process that automatically translates a software program in a high-level language into a low-level hardware description. However, the hardware designs produced by HLS tools still suffer from a significant…

Programming Languages · Computer Science 2023-08-16 Jianyi Cheng , Samuel Coward , Lorenzo Chelini , Rafael Barbalho , Theo Drane

The solar atmosphere is extremely dynamic, and many important phenomena develop on small scales that are unresolved in observations with the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO). For…

Solar and Stellar Astrophysics · Physics 2015-08-06 Irina N. Kitiashvili , Sebastien Couvidat , Andreas Lagg

Regularization of the inverse problem is a complex issue when using Near-field Acoustic Holography (NAH) techniques to identify the vibrating sources. This paper shows that, for convex homogeneous plates with arbitrary boundary conditions,…

Data Analysis, Statistics and Probability · Physics 2015-06-05 Gilles Chardon , Laurent Daudet , Antoine Peillot , François Ollivier , Nancy Bertin , Rémi Gribonval

We present here numerical simulations of surface solar convection which cover a box of 30$\times30\times$3.2 Mm$^3$ with a resolution of 315$\times315\times$82, which is used to investigate the dynamics of scales larger than granulation. No…

Astrophysics · Physics 2010-11-11 M. Rieutord , H. -G. Ludwig , T. Roudier , A. Nordlund , R. Stein

An essential ingredient in kinematic dynamo models is the velocity field within the solar convection zone. In particular, the differential rotation is now well constrained by helioseismic observations. Helioseismology also gives us…

Astrophysics · Physics 2009-06-30 Andrés Muñoz-Jaramillo , Dibyendu Nandy , Petrus C. H. Martens

The differential rotation of the sun, as deduced from helioseismology, exhibits a prominent radial shear layer near the top of the convection zone wherein negative radial gradients of angular velocity are evident in the low- and…

Astrophysics · Physics 2009-11-07 M. L. DeRosa , P. A. Gilman , J. Toomre

We report on a new phenomenon of `alignment' of supergranulation cells in the polar regions of the Sun. Recent high-resolution datasets obtained by the Solar Optical Telescope onboard the Hinode satellite enabled us to investigate…

Solar and Stellar Astrophysics · Physics 2010-12-20 Kaori Nagashima , Junwei Zhao , Alexander G. Kosovichev , Takashi Sekii

Using solar-cycle long helioseismic measurements of meridional and zonal flows in the near-surface shear layer (NSSL) of the Sun, we study their spatio-temporal variations and connections to active regions. We find that near-surface inflows…

Solar and Stellar Astrophysics · Physics 2025-12-16 Anisha Sen , S. P. Rajaguru , Abhinav Govindan Iyer , Ruizhu Chen , Junwei Zhao , Shukur Kholikov

Since the first observations of solar oscillations, helioseismology has been one of the most successful fields of astrophysics. Data of high quality were obtained through the implementation of networks of ground-based observatories such as…

Solar and Stellar Astrophysics · Physics 2019-06-20 G. Buldgen , A. Noels , S. Salmon

It is of great importance to preserve locality and similarity information in semi-supervised learning (SSL) based applications. Graph based SSL and manifold regularization based SSL including Laplacian regularization (LapR) and Hypergraph…

Computer Vision and Pattern Recognition · Computer Science 2019-05-01 Xueqi Ma , Weifeng Liu , Shuying Li , Yicong Zhou

We performed 3D numerical simulations of the solar surface wave field for the quiet Sun and for three models with different localized sound-speed variations in the interior with: (i) deep, (ii) shallow, and (iii) two-layer structures. We…

Solar and Stellar Astrophysics · Physics 2012-09-24 Konstantin V. Parchevsky , Junwei Zhao , Thomas Hartlep , Alexander G. Kosovichev

Time-distance helioseismology provides information about vector flows in the near-surface layers of the Sun by measuring wave travel times between points on the solar surface. Specific spatial averages of travel times have been proposed for…

Solar and Stellar Astrophysics · Physics 2015-01-05 Jan Langfellner , Laurent Gizon , Aaron C. Birch

Horizontally-periodic Boussinesq Rayleigh-B\'enard Convection (RBC) is a simple model system to study the formation of large-scale structures in turbulent convective flows. We performed a suite of 2D numerical simulations of RBC between…

Solar and Stellar Astrophysics · Physics 2025-12-23 F. Kupka , D. Fabbian , F. Zaussinger , D. Krüger , L. Gizon

Flows on the solar surface are linked to solar activity, and LCT is one of the standard techniques for capturing the dynamics of these processes by cross-correlating solar images. However, the link between contrast variations in successive…

Solar and Stellar Astrophysics · Physics 2015-06-16 M. Verma , M. Steffen , C. Denker

Global spectral analysis (GSA) is used as a tool to test the accuracy of numerical methods with the help of canonical problems of convection and convection-diffusion equation which admit exact solutions. Similarly, events in turbulent flows…

Numerical Analysis · Mathematics 2022-03-21 Tapan K. Sengupta , Suman V. K. , Prasannabalaji Sundaram , Aditi Sengupta

In this dissertation, several components of large-scale solar flows are studied observationally: solar equatorial Rossby waves (waves of radial vorticity), large-scale convection, and surface flows around active regions. Maps of horizontal…

Solar and Stellar Astrophysics · Physics 2023-01-25 Bastian Proxauf

A set of 464-min high-resolution high-cadence observations were acquired for a region near the Sun's disk center using the Interferometric BI-dimensional Spectrometer (IBIS) installed at the Dunn Solar Telescope. Ten sets of Dopplergrams…

Solar and Stellar Astrophysics · Physics 2022-05-24 Junwei Zhao , S. P. Rajaguru , Ruizhu Chen