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Modern stellar structure and evolution theory experiences a lack of observational calibrations for the interior physics of intermediate- and high-mass stars. This leads to discrepancies between theoretical predictions and observed phenomena…

Recent work on Neural Radiance Fields (NeRF) has demonstrated significant advances in high-quality view synthesis. A major limitation of NeRF is its low rendering efficiency due to the need for multiple network forwardings to render a…

Computer Vision and Pattern Recognition · Computer Science 2023-08-23 Yushuang Wu , Xiao Li , Jinglu Wang , Xiaoguang Han , Shuguang Cui , Yan Lu

Fourier synthesis is one of the foundations of physical optics. Spatial Fourier optics is a basis for understanding optical imaging, microscopy, and holography. In conventional Fourier optics, the complex spatial field distribution in the…

Optics · Physics 2025-04-29 Murat Yessenov , Ayman F. Abouraddy

Opacity is a key ingredient of stellar structure and evolution. In the present work, we recall the role of opacity in asteroseismology, focusing mainly on two kinds of astrophysical objects: $\beta$ Cephei-type stars, and the Sun. The…

Solar and Stellar Astrophysics · Physics 2019-04-30 Jean-Christophe Pain , Franck Gilleron

Radiative transfer calculations have predicted intensity enhancements for optically thick emission lines, as opposed to the normal intensity reductions, for astrophysical plasmas under certain conditions. In particular, the results are…

Solar and Stellar Astrophysics · Physics 2015-05-30 F. P. Keenan , D. J. Christian , S. J. Rose , M. Mathioudakis

We extend models of our Galaxy based on distribution functions (DFs) that are analytic functions of the action integrals to extended distribution functions (EDFs), which have an analytic dependence on metallicity as well. We use a simple,…

Astrophysics of Galaxies · Physics 2015-06-03 Jason L. Sanders , James Binney

Transmittance estimators such as Occupancy Grid (OG) can accelerate the training and rendering of Neural Radiance Field (NeRF) by predicting important samples that contributes much to the generated image. However, OG manages occupied…

Computer Vision and Pattern Recognition · Computer Science 2024-04-17 Yoshio Kato , Shuhei Tarashima

Orthogonal time frequency space (OTFS) modulation was proposed to tackle the destructive Doppler effects in wireless communications, with potential applications to many other areas. In this paper, we investigate its application to radar…

Information Theory · Computer Science 2019-01-29 P. Raviteja , Khoa T. Phan , Yi Hong , Emanuele Viterbo

The stellar population synthesis in unresolved composite objects is a very tricky problem. Indeed, it is a degenerate problem since many parameters affect the observables. The stellar population synthesis issue thus deserves a deep and…

Astrophysics · Physics 2009-11-10 J. Moultaka

Orthogonal time frequency space (OTFS) modulation has recently been identified as a suitable waveform for joint radar and communication systems. Focusing on the effect of data modulation on the radar sensing performance, we derive the…

Signal Processing · Electrical Eng. & Systems 2024-03-14 Shalanika Dayarathna , Peter Smith , Rajitha Senanayake , Jamie Evans

In this paper, we present a new approach for uncertainty-aware retinal layer segmentation in Optical Coherence Tomography (OCT) scans using probabilistic signed distance functions (SDF). Traditional pixel-wise and regression-based methods…

Image and Video Processing · Electrical Eng. & Systems 2024-12-09 Mohammad Mohaiminul Islam , Coen de Vente , Bart Liefers , Caroline Klaver , Erik J Bekkers , Clara I. Sánchez

We compare the performance of an approach using real frequency dependent polarizability to compute optical absorption spectra to linear-response time-dependent density functional theory (TD-DFT) for small organic dyes, oligomers of…

Materials Science · Physics 2018-05-22 Ang Siong Tuan , Amrita Pal , Sergei Manzhos

Echelle spectrographs with their high resolution plays important role in determination of characteristics of stellar lines. Wide field of applications is focused mainly on the measurements of precise radial velocity applied in exoplanetary…

Instrumentation and Methods for Astrophysics · Physics 2016-02-16 Romana Grossová

Constellation shaping is a practical and effective technique to improve the performance and the rate adaptivity of optical communication systems. In principle, it could also be used to mitigate the impact of nonlinear effects, possibly…

Information Theory · Computer Science 2022-06-08 Marco Secondini , Stella Civelli , Enrico Forestieri , Lareb Zar Khan

The Orientation Distribution Function (ODF) characterizes key brain microstructural properties and plays an important role in understanding brain structural connectivity. Recent works introduced Implicit Neural Representation (INR) based…

Image and Video Processing · Electrical Eng. & Systems 2024-09-17 Mohammed Munzer Dwedari , William Consagra , Philip Müller , Özgün Turgut , Daniel Rueckert , Yogesh Rathi

In order to explore how the ubiquitous stochastic low-frequency (SLF) variability of O-type stars is related to various stellar characteristics, we compiled a sample of 150 O-type stars observed via ground-based spectroscopic surveys,…

Solar and Stellar Astrophysics · Physics 2024-08-22 Dong-Xiang Shen , Chun-Hua Zhu , Guo-Liang Lv , Xi-zhen Lu , Xiao-long He

High mobility environment leads to severe Doppler effects and poses serious challenges to the conventional physical layer based on the widely popular orthogonal frequency division multiplexing (OFDM). The recent emergence of orthogonal time…

Signal Processing · Electrical Eng. & Systems 2025-02-14 Qinwen Deng , Yao Ge , Zhi Ding

We investigate the ability of infrared integral-field spectrographs to map the velocity fields of high redshift galaxies, presenting a formalism which may be applied to any telescope and imaging spectrograph system. We discuss the 5-sigma…

Astrophysics · Physics 2008-11-26 David R. Law , Charles C. Steidel , Dawn K. Erb

Kepler seeks to detect sequences of transits of Earth-size exoplanets orbiting Solar-like stars. Such transit signals are on the order of 100 ppm. The high photometric precision demanded by Kepler requires detailed knowledge of how the…

Planetary studies demand precise and accurate stellar parameters as input to infer the planetary properties. Different methods often provide different results that could lead to biases in the planetary parameters. In this work, we present a…

Solar and Stellar Astrophysics · Physics 2014-10-22 M. Tsantaki , S. G. Sousa , N. C. Santos , M. Montalto , E. Delgado-Mena , A. Mortier , V. Adibekyan , G. Israelian