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In this work we study the transport properties of non-interacting overdamped particles, moving on tilted disordered potentials, subjected to Gaussian white noise. We give exact formulas for the drift and diffusion coefficients for the case…

Statistical Mechanics · Physics 2014-09-04 Raul Salgado-Garcia

Generating large-scale, physically consistent AC Optimal Power Flow (ACOPF) datasets is essential for modern data-driven power system applications. The central challenge lies in balancing solution accuracy with computational efficiency.…

Systems and Control · Electrical Eng. & Systems 2026-02-04 Shashank Shekhar , Abhinav Karn , Kris Keshav , Shivam Bansal , Parikshit Pareek

We investigate crystallization-driven convection in carbon-oxygen white dwarfs. We present a version of the mixing length theory (MLT) that self-consistently includes the effects of thermal diffusion and composition gradients, and provides…

Solar and Stellar Astrophysics · Physics 2024-07-01 Matias Castro-Tapia , Andrew Cumming , J. R. Fuentes

Using the most recent results about white dwarfs in 10 open clusters, we revisit semi-empirical estimates of the initial-final mass relation in star clusters, with emphasis on the use of stellar evolution models. We discuss the influence of…

Astrophysics · Physics 2011-02-11 Maurizio Salaris , Aldo Serenelli , Achim Weiss , Marcelo Miller Bertolami

Diffusion Models (DMs) have demonstrated state-of-the-art performance in content generation without requiring adversarial training. These models are trained using a two-step process. First, a forward - diffusion - process gradually adds…

Computer Vision and Pattern Recognition · Computer Science 2024-03-13 Anwaar Ulhaq , Naveed Akhtar

The helium-atmosphere (DB) white dwarfs are commonly thought to be the descendants of the hotter PG1159 stars, which initially have uniform He/C/O atmospheres. In this evolutionary scenario, diffusion builds a pure He surface layer which…

Astrophysics · Physics 2007-05-23 T. S. Metcalfe , R. E. Nather , T. K. Watson , S. -L. Kim , B. -G. Park , G. Handler

Major drawback of studying diffusion in multi-component systems is the lack of suitable techniques to estimate the diffusion parameters. In this study, a generalized treatment to determine the intrinsic diffusion coefficients in…

Materials Science · Physics 2022-08-23 Sangeeta Santra , Aloke Paul

Various bias-correction methods such as EXTRA, gradient tracking methods, and exact diffusion have been proposed recently to solve distributed {\em deterministic} optimization problems. These methods employ constant step-sizes and converge…

Machine Learning · Computer Science 2023-07-19 Kun Yuan , Sulaiman A. Alghunaim , Bicheng Ying , Ali H. Sayed

Traditional elastic wavefield separation methods, while accurate, often demand substantial computational resources, especially for large geological models or 3D scenarios. Purely data-driven neural network approaches can be more efficient,…

Geophysics · Physics 2025-07-01 Shijun Cheng , Xinru Mu , Tariq Alkhalifah

Many isolated, old white dwarfs (WDs) show surprising evidence of metals in their photospheres. Given that the timescale for gravitational sedimentation is astronomically short, this is taken as evidence for ongoing accretion, likely of…

Solar and Stellar Astrophysics · Physics 2018-06-13 Evan B. Bauer , Lars Bildsten

Diffusion models have attained remarkable success in the domains of image generation and editing. It is widely recognized that employing larger inversion and denoising steps in diffusion model leads to improved image reconstruction quality.…

Computer Vision and Pattern Recognition · Computer Science 2024-01-05 Chen Hou , Guoqiang Wei , Zhibo Chen

Various flame tracking techniques are often used in hydrodynamic simulations. Their use is indispensable when resolving actual scale of the flame is impossible. We show that parameters defining "artificial flame" propagation found from…

Astrophysics · Physics 2007-05-23 Andrey V. Zhiglo

Mathematical models describing the spatial spreading and invasion of populations of biological cells are often developed in a continuum modelling framework using reaction-diffusion equations. While continuum models based on linear diffusion…

Cellular Automata and Lattice Gases · Physics 2024-01-23 Matthew J Simpson , Keeley M Murphy , Scott W McCue , Pascal R Buenzli

A microscopic model able to describe simultaneously the dynamic viscosity and the self-diffusion coefficient of fluids is presented. This model is shown to emerge from the introduction of fractional calculus in a usual model of condensed…

Statistical Mechanics · Physics 2021-11-24 F. Aitken , F. Volino

Experimental studies of systems containing active proteins that undergo conformational changes driven by catalytic chemical reactions have shown that the diffusion coefficients of passive tracer particles and active molecules are larger…

Soft Condensed Matter · Physics 2017-02-27 Matthew Dennison , Raymond Kapral , Holger Stark

Despite Flow Matching and diffusion models having emerged as powerful generative paradigms for continuous variables such as images and videos, their application to high-dimensional discrete data, such as language, is still limited. In this…

Machine Learning · Computer Science 2024-11-06 Itai Gat , Tal Remez , Neta Shaul , Felix Kreuk , Ricky T. Q. Chen , Gabriel Synnaeve , Yossi Adi , Yaron Lipman

We discuss the potentials of several experimental configurations dedicated to direct measurements of charged cosmic ray (CR) nuclei at energies $\gsim$ 100 GeV/n. Within a two-zone propagation model for stable CRs, we calculate light…

Astrophysics · Physics 2009-11-10 A. Castellina , F. Donato

We present full evolutionary calculations appropriate for the study of hydrogen-rich DA white dwarfs. This is done by evolving white dwarf progenitors from the zero age main sequence, through the core hydrogen burning phase, the helium…

We present new cooling sequences, color-magnitude diagrams, and color-color diagrams for cool white dwarfs with pure hydrogen atmospheres down to an effective temperature $\te=1500$ K. We include a more detailed treatment of the physics of…

Astrophysics · Physics 2009-10-31 Gilles Chabrier , Pierre Brassard , Gilles Fontaine , Didier Saumon

Bimolecular diffusion coefficients are important parameters used by atmospheric models to calculate altitude profiles of minor constituents in an atmosphere. Unfortunately, laboratory measurements of these coefficients were never conducted…

Earth and Planetary Astrophysics · Physics 2015-10-28 Sylvain Plessis , Damon McDougall , Kathy Mandt , Thomas Greathouse , Adrienn Luspay-Kuti