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Generative (diffusion) priors demonstrate remarkable performance in addressing inverse problems in imaging. Yet, for scientific and medical imaging, it is crucial that reconstruction techniques remain stable and reliable under imperfect…

Image and Video Processing · Electrical Eng. & Systems 2026-05-12 Alexander Denker , Johannes Hertrich , Sebastian Neumayer

The development of radiation hydrodynamical methods that are able to follow gas dynamics and radiative transfer self-consistently is key to the solution of many problems in numerical astrophysics. Such fluid flows are highly complex, rarely…

Aims. The main goal of this paper is to present an accurate and efficient numerical strategy for solving the radiative transfer problem for polarised radiation in strong resonance lines forming out of local thermodynamic equilibrium, taking…

We consider the inverse problem of reconstructing the scattering and absorption coefficients using boundary measurements for a time dependent radiative transfer equation (RTE). As the measurement is mostly polluted by errors, both…

Numerical Analysis · Mathematics 2017-08-11 Ke Chen , Qin Li , Li Wang

We further develop a simple modification of Runge--Kutta methods that guarantees conservation or stability with respect to any inner-product norm. The modified methods can be explicit and retain the accuracy and stability properties of the…

Numerical Analysis · Mathematics 2019-05-27 David I. Ketcheson

In present paper, we establish sufficient conditions for existence and stability of solutions for system of nonlinear implicit fractional differential equations. The main techniques are based on method of successive approximations. Finally,…

Classical Analysis and ODEs · Mathematics 2017-07-25 D. B. Dhaigude , Sandeep P. Bhairat

The propagation of stable coherent entities of an electromagnetic field in nonlinear media with parameters varying in space can be described in the framework of iterations of nonlinear integral transformations. It is shown that for a set of…

Pattern Formation and Solitons · Physics 2020-12-10 A. Yu. Okulov

This paper is concerned with the study, by computational means, of the generation and stability of solitary-wave solutions of generalized versions of the Benjamin equation. The numerical generation of the solitary-wave profiles is…

Numerical Analysis · Mathematics 2017-12-08 Vassilios A. Dougalis , Angel Duran , Dimitrios Mitsotakis

Many physical problems can be formulated as operator equations of the form Au = f. If these operator equations are ill-posed, we then resort to finding the approximate solutions numerically. Ill-posed problems can be found in the fields of…

Numerical Analysis · Mathematics 2016-11-11 Suresh B. Srinivasamurthy

In modern power systems, the operating point, at which the demand and supply are balanced, may take different values due to changes in loads and renewable generation levels. Understanding the dynamics of stressed power systems with a range…

Systems and Control · Computer Science 2017-10-31 Thanh Long Vu , Hung Dinh Nguyen , Alexandre Megretski , Jean-Jacques Slotine , Konstantin Turitsyn

This work obtains a fixed-point equation for the solution of linear parabolic partial differential problems based on solutions to heat problems. This is a pointwise equality, so we have required non-standard techniques that involve the…

Analysis of PDEs · Mathematics 2025-05-29 Inmaculada Gayte Delgado , Irene Marín Gayte

In this paper we introduce the randomised stability constant for abstract inverse problems, as a generalisation of the randomised observability constant, which was studied in the context of observability inequalities for the linear wave…

Analysis of PDEs · Mathematics 2020-07-16 Giovanni S. Alberti , Yves Capdeboscq , Yannick Privat

We describe two separate wavelength discretization schemes that can be used in the numerical solution of the comoving frame radiative transfer equation. We present an improved second order discretization scheme and show that it leads to…

Astrophysics · Physics 2009-11-10 Peter H. Hauschildt , E. Baron

Motivated by studies on fully discrete numerical schemes for linear hyperbolic conservation laws, we present a framework on analyzing the strong stability of explicit Runge-Kutta (RK) time discretizations for semi-negative autonomous linear…

Numerical Analysis · Mathematics 2018-11-28 Zheng Sun , Chi-Wang Shu

Recently, an approach known as relaxation has been developed for preserving the correct evolution of a functional in the numerical solution of initial-value problems, using Runge-Kutta methods. We generalize this approach to multistep…

Numerical Analysis · Mathematics 2020-11-26 Hendrik Ranocha , Lajos Lóczi , David I. Ketcheson

In this paper we present a characteristic method for solving the transfer equation in differentially moving media in a curved spacetime. The method is completely general, but its capabilities are exploited at best in presence of symmetries,…

Astrophysics · Physics 2009-10-28 Silvia Zane , Roberto Turolla , Luciano Nobili , Myris Erna

In this paper, we consider robust stability analysis of large-scale sparsely interconnected uncertain systems. By modeling the interconnections among the subsystems with integral quadratic constraints, we show that robust stability analysis…

Optimization and Control · Mathematics 2016-11-15 Martin S. Andersen , Sina Khoshfetrat Pakazad , Anders Hansson , Anders Rantzer

The classical Calder\'on problem with partial data is known to be log-log stable in some special cases, but even the uniqueness problem is open in general. We study the partial data stability of an analogous inverse fractional conductivity…

Analysis of PDEs · Mathematics 2025-05-27 Giovanni Covi , Antti Kujanpää , Jesse Railo

This paper explores the analytical approach for obtaining the multiple solutions of three-wave interacting system in (1+1) dimensions. We present a novel approach by expressing the wave solutions in terms of Jacobi elliptic functions and…

Pattern Formation and Solitons · Physics 2024-03-14 Niladri Ghosh , Amiya Das , Debraj Nath

Conditional stability estimates allow us to characterize the degree of ill-posedness of many inverse problems, but without further assumptions they are not sufficient for the stable solution in the presence of data perturbations. We here…

Numerical Analysis · Mathematics 2018-10-17 Herbert Egger , Bernd Hofmann