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Related papers: A New Exact Method for Line Radiative Transfer

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We present MOLPOP-CEP, a universal line transfer code that allows the exact calculation of multi-level line emission from a slab with variable physical conditions for any arbitrary atom or molecule for which atomic data exist. The code…

Instrumentation and Methods for Astrophysics · Physics 2018-09-12 A. Asensio Ramos , M. Elitzur

We have adapted Coupled Escape Probability, a new exact method of solving radiative transfer problems, for use in asymmetrical spherical situations. Our model is intended specifically for use in modeling optically thick cometary comae,…

Earth and Planetary Astrophysics · Physics 2012-12-07 Alan M. Gersch , Michael F. A'Hearn

Radiative transfer effects need to be taken into account when analysing spectral line observations. When the data are not sufficient for detailed modelling, simpler methods are needed. The escape probability formalism (EPF) is one such…

Instrumentation and Methods for Astrophysics · Physics 2025-04-16 Mika Juvela

Context: The solution of the nonlocal thermodynamical equilibrium (non-LTE) radiative transfer equation usually relies on stationary iterative methods, which may falsely converge in some cases. Furthermore, these methods are often unable to…

Solar and Stellar Astrophysics · Physics 2015-07-29 Julien Lambert , Eric Josselin , Nils Ryde , Alexandre Faure

The problem of optimal power allocation among the relays in a two-hop decode-and-forward cooperative relay network with independent Rayleigh fading channels is considered. It is assumed that only the relays that decode the source message…

Information Theory · Computer Science 2015-05-27 Arash Khabbazibasmenj , Sergiy A. Vorobyov

We consider the problem of extrapolating the perturbation series for the dilute Fermi gas in three dimensions to the unitary limit of infinite scattering length and into the BEC region, using the available strong-coupling information to…

Quantum Gases · Physics 2021-04-27 Corbinian Wellenhofer , Daniel R. Phillips , Achim Schwenk

The Continuous Polytope Escape Problem (CPEP) asks whether every trajectory of a linear differential equation initialised within a convex polytope eventually escapes the polytope. We provide a polynomial-time algorithm to decide CPEP for…

Dynamical Systems · Mathematics 2020-01-23 Julian D'Costa , Engel Lefaucheux , Joël Ouaknine , James Worrell

We introduce the Quantization Monte Carlo method to solve thermal radiative transport equations with possibly several collision regimes, ranging from few collisions to massive number of collisions per time unit. For each particle in a given…

Computational Physics · Physics 2024-09-13 Laetitia Laguzet , Gabriel Turinici

With the advent of the present and future spatial X-ray missions, it becomes crucial to model correctly the line spectrum of X-ray emitting media. We have built a photoionization code, Titan, solving the transfer of a thousand lines and of…

Astrophysics · Physics 2009-11-10 Suzy Collin , Anne-Marie Dumont , Olivier Godet

The Symmetric Exclusion Process (SEP), in which particles hop symmetrically on a discrete line with hard-core constraints, is a paradigmatic model of subdiffusion in confined systems. This anomalous behavior is a direct consequence of…

Statistical Mechanics · Physics 2018-06-13 Alexis Poncet , Olivier Bénichou , Vincent Démery , Gleb Oshanin

For the enhancement of the transient stability of power systems, the key is to define a quantitative optimization formulation with system parameters as decision variables. In this paper, we model the disturbances by Gaussian noise and…

Systems and Control · Electrical Eng. & Systems 2023-09-14 Xian Wu , Kaihua Xi , Aijie Cheng , Chenghui Zhang , Hai Xiang Lin

Sublinear time complexity is required by the massively parallel computation (MPC) model. Breaking dynamic programs into a set of sparse dynamic programs that can be divided, solved, and merged in sublinear time. The rectangle escape problem…

Computational Geometry · Computer Science 2023-09-04 Sepideh Aghamolaei , Mohammad Ghodsi

Multi-cell processing, also called Coordinated Multiple Point (CoMP), is a very promising distributed multi-antennas technique that uses neighbour cell's antennas. This is expected to be part of next generation cellular networks standards…

Networking and Internet Architecture · Computer Science 2011-10-14 Virgile Garcia , Jean-Marie Gorce , Nikolai Lebedev

Exact inference in the linear regression model with spike and slab priors is often intractable. Expectation propagation (EP) can be used for approximate inference. However, the regular sequential form of EP (R-EP) may fail to converge in…

Machine Learning · Statistics 2011-12-13 José Miguel Hernández-Lobato , Daniel Hernández-Lobato

We introduce and analyze a lower envelope method (LEM) for the tracking of interfaces motion in multiphase problems. The main idea of the method is to define the phases as the regions where the lower envelope of a set of functions coincides…

Numerical Analysis · Mathematics 2021-12-07 Antoine Laurain

The purpose of this article is to describe the two approaches to compute exact formulas (which are amenable to asymptotic analysis) for the probability distribution of the current of particles past a given site in the asymmetric simple…

Probability · Mathematics 2013-03-13 Ivan Corwin

We consider multi-value expansion planning (MEP), a general bilevel optimization model in which a planner optimizes arbitrary functions of the dispatch outcome in the presence of a partially controllable, competitive electricity market. The…

Optimization and Control · Mathematics 2024-04-02 Anthony Degleris , Abbas El Gamal , Ram Rajagopal

The rapid integration of Renewable Energy Sources (RESs) strengthens the need for a power network that can robustly handle the system's uncertain scenarios. Thus, this paper proposes the first nonlinear novel dual based bi-level approach…

Systems and Control · Electrical Eng. & Systems 2021-11-11 P. Naga Yasasvi , Abheejeet Mohapatra , Suresh Chandra Srivastava

We develop a new probabilistic method for deriving deviation estimates in directed planar polymer and percolation models. The key estimates are for exit points of geodesics as they cross transversal down-right boundaries. These bounds are…

Probability · Mathematics 2023-08-30 Elnur Emrah , Christopher Janjigian , Timo Seppäläinen

Expectation propagation (EP) is a powerful approximate inference algorithm. However, a critical barrier in applying EP is that the moment matching in message updates can be intractable. Handcrafting approximations is usually tricky, and…

Machine Learning · Statistics 2019-11-11 Zheng Wang , Shandian Zhe
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