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This paper presents a convex, multi-period, AC-feasible Optimal Power Flow (OPF) framework that robustly dispatches flexible demand-side resources in unbalanced distribution feeders against uncertainty in very-short timescale solar…

Optimization and Control · Mathematics 2020-05-20 Nawaf Nazir , Mads Almassalkhi

We present new methods for radiative transfer on hierarchial grids. We develop a new method for calculating the scattered flux that employs the grid structure to speed up the computation. We describe a novel subiteration algorithm that can…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 T. Lunttila , M. Juvela

One of the fundamental limits of classical optical microscopy is the diffraction limit of optical resolution. It results from the finite bandwidth of the optical transfer function (or OTF) of an optical microscope, which restricts the…

Optics · Physics 2022-03-11 Sjoerd Stallinga , Niels Radmacher , Antoine Delon , Jörg Enderlein

Polycrystalline materials, such as metals, are comprised of heterogeneously oriented crystals. Observed crystal orientations are modelled as a sample from an orientation distribution function (ODF), which determines a variety of material…

Applications · Statistics 2020-12-10 James Matuk , Oksana Chkrebtii , Stephen Niezgoda

The Doppler beaming effect, induced by the reflex motion of stars, introduces flux modulations and serves as an efficient method to photometrically determine mass functions for a large number of close binary systems, particularly those…

Solar and Stellar Astrophysics · Physics 2024-08-08 Chuanjie Zheng , Yang Huang , Jifeng Liu , Youjun Lu , Henggeng Han , Yuan Tan , Timothy C. Beers

The interest in using optical transition radiation (OTR) in high energy (multiGeV) beam diagnostics has motivated theoretical and experimental investigations on the limitations brought by diffraction on the attainable resolution. This paper…

Accelerator Physics · Physics 2007-05-23 X. Artru , R. Chehab , K. Honkavaara , A. Variola

Local density approximation (LDA) to the density functional theory (DFT) has continuous derivative of total energy as a number of electrons function and continuous exchange-correlation potential, while in exact DFT both should be…

Strongly Correlated Electrons · Physics 2010-06-28 V. I. Anisimov , A. V. Kozhevnikov , M. A. Korotin , A. V. Lukoyanov , D. A. Khafizullin

Inferring brain connectivity and structure \textit{in-vivo} requires accurate estimation of the orientation distribution function (ODF), which encodes key local tissue properties. However, estimating the ODF from diffusion MRI (dMRI)…

Image and Video Processing · Electrical Eng. & Systems 2024-02-07 William Consagra , Lipeng Ning , Yogesh Rathi

The surfaces of rotating stars serve as a window into their interiors, magnetic dynamos, and are important in other areas including exoplanet discovery and atmospheric characterization. While indirect techniques such as photometry and…

Instrumentation and Methods for Astrophysics · Physics 2025-10-01 Shashank Dholakia , Benjamin J. S. Pope

The point-spread function (PSF) of an adaptive optics (AO) system is often poorly known. This ignorance can lead to significant systematic errors in photometry. Since the degree of AO correction is sensitive to the observing conditions:…

Astrophysics · Physics 2010-11-11 Christopher D. Sheehy , Nate McCrady , James R. Graham

Some pulsating stars are good clocks. When they are found in binary stars, the frequencies of their luminosity variations are modulated by the Doppler effect caused by orbital motion. For each pulsation frequency this manifests itself as a…

Solar and Stellar Astrophysics · Physics 2015-06-04 Hiromoto Shibahashi , Donald W. Kurtz

Tools for the spectroscopic determination of fundamental stellar parameters should not only comprise customized solutions for one particular survey or instrument, but, in order to enable cross-survey comparability, they should also be…

Solar and Stellar Astrophysics · Physics 2018-11-21 Michael Hanke , Camilla Juul Hansen , Andreas Koch , Eva K. Grebel

Orthogonal time frequency space (OTFS) modulation has been confirmed to provide significant performance advantages against Doppler in high-mobility scenarios. The core feature of OTFS is that the time-variant channel is converted into a…

Information Theory · Computer Science 2021-03-31 Haoyan Liu , Yanming Liu , Min Yang , Qiongjie Zhang

We present a new approach for constructing optical phase-space-time-frequency tomography (OPSTFT) of an optical wave field. This tomography can be measured by using a novel four-window optical imaging system based on two local oscillator…

Quantum Physics · Physics 2015-05-27 Paul Rojas , Rachel Blaser , Yong Meng Sua , Kim Fook Lee

Dynamic imaging through time-varying scattering media is ubiquitous in real-world settings, yet it remains a defining unsolved problem as rapid spatiotemporal fluctuations overwhelm standard reconstruction pipelines that often rely on…

Optics · Physics 2025-11-25 Yunong Sun , Fei Xia

Radiative opacity is an important quantity in the modeling of stellar structure and evolution. In the present work we recall the role of opacity in the interpretation of pulsations of different kinds of stars. The detailed opacity code…

Solar and Stellar Astrophysics · Physics 2022-09-26 Jean-Christophe Pain , Franck Gilleron , Maxime Comet

Processing of Diffusion MRI data obtained from High Angular Resolution measurements consists of a series of steps, starting with the estimation of an orientation distribution function (ODF), which is then used as input for e.g. tractography…

Numerical Analysis · Mathematics 2015-12-23 T. Hohage , C. Rügge

Context. Recently our ability to study stars using asteroseismic techniques has increased dramatically, largely through the use of space based photometric observations. Work has also been done using ground based spectroscopic observations…

Solar and Stellar Astrophysics · Physics 2018-10-03 Jesper Schou

(Abridged) We describe a new method to extract spectra of stars from observations of crowded stellar fields with integral field spectroscopy (IFS). Our approach extends the well-established concept of crowded field photometry in images into…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Sebastian Kamann , Lutz Wisotzki , Martin M. Roth

Context. As increasingly more spectroscopic data are being delivered by medium- and high-resolving power multi-object spectrographs, more automatic stellar parameter determination softwares are being developed. The quality of the spectra…

Solar and Stellar Astrophysics · Physics 2012-09-04 Helene Posbic , David Katz , Elisabetta Caffau , Piercarlo Bonifacio , Ana Gomez , Luca Sbordone , Frederic Arenou