Results 61 to 70 of about 3,180,909 (182)

A Unified Framework From Boltzmann Transport to Proton Treatment Planning

Studies in Applied Mathematics, Volume 157, Issue 2, August 2026.
ABSTRACT We develop a unified stochastic–deterministic framework for proton transport in radiotherapy. The deterministic formulation is based on a Boltzmann–Fokker–Planck (BFP) equation with continuous slowing‐down, angular diffusion, and scattering terms, posed in a kinetic variational setting.
Andreas E. Kyprianou, Aaron Pim, Tristan Pryer   +2 more
wiley   +1 more source

Particular case of operator calculus for generalized functions with supports in cone

Karpatsʹkì Matematičnì Publìkacìï, 2009
In this work the construction of functional calculus for strongly continuous semigroups of operators in Schwartz distribution algebra on some cone is generalized.
A. V. Solomko
doaj  

A Theory of Strongly Continuous Semigroups in Terms of Lie Generators

Journal of Functional Analysis, 1996
For a separable complete metric space \(X\) denote by \({\mathcal F} (X)\) the set of all continuous transformations of \(X\) into itself and by \({\mathcal C} (X)\) the linear space of all bounded continuous real-valued functions from \(X\). A function \(T: [0, \infty)\to {\mathcal F} (X)\) is called jointly continuous semigroup in \(X\) if \(T(0 ...
Dorroh, J.R., Neuberger, J.W.
openaire   +1 more source

KdV limit for the Vlasov–Poisson–Landau system

Journal of the London Mathematical Society, Volume 114, Issue 2, August 2026.
Abstract We are concerned with the fluid limit to KdV equations for the one‐dimensional Vlasov–Poisson–Landau system that describes the dynamics of ions in plasma with the electron density determined by the self‐consistent electric potential through the so‐called Boltzmann relation. Formally, it is well known that as the Knudsen number ε→0$\varepsilon \
Renjun Duan, Dongcheng Yang, Hongjun Yu
wiley   +1 more source

UN PROBLEMA TRIDIMENSIONALE DI TRASPORTO FUORI DI UNA SFERA RIFLETTENTE

Ratio Mathematica, 1991
In this paper we study the linear monoenergetic Boltzmann equation in the space external to a sphere ofradius n> f} with specular refiectionboundary conditions- By means oftheory of linear positive operator semigroups in Banach spaces we Show that ...
L Bassi, P Gamba
doaj  

Semigroups and Evolution Equations in Modular Function Spaces

Axioms
This paper develops the theory of strongly continuous semigroups and abstract evolution equations in modular function spaces. We study the autonomous problem u˙(t)=Bu(t) with initial condition u(0)=u0∈Lρ, where B is the infinitesimal generator of a ...
Mostafa Bachar
doaj   +1 more source

Positivity and contractivity in the dynamics of clusters’ splitting with derivative of fractional order

Open Mathematics, 2015
Classical models of clusters’ fission have failed to fully explain strange phenomenons like the phenomenon of shattering (Ziff et al., 1987) and the sudden appearance of infinitely many particles in some systems with initial finite particles number ...
Goufo Emile Franc Doungmo, Mugisha Stella   +1 more
doaj   +1 more source

On the theories classified by an étendue

Bulletin of the London Mathematical Society, Volume 58, Issue 7, July 2026.
Abstract We give a model‐theoretic characterisation of the geometric theories classified by étendues—the ‘locally localic’ topoi. They are the theories where each model is determined, syntactically and semantically, by any witness of a fixed collection of formulae.
Joshua L. Wrigley
wiley   +1 more source

On the Compactness of Strongly Continuous Semigroups and Cosine Functions of Operators [PDF]

Proceedings of the American Mathematical Society, 1995
In this note we relate two notions of compactness for strongly continuous semigroups of linear operators and cosine functions of linear operators. Specifically, if T denotes a strongly continuous semigroup of linear operators defined on a Banach space X
openaire   +2 more sources

A new look at boundary perturbations of generators

Electronic Journal of Differential Equations, 2004
In this paper we show that Greiner's results on boundary perturbation can be obtained systematically and partially generalised by applying additive perturbation theorems to appropriate operator matrices.
Gregor Nickel
doaj