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On numerical solution to the problem of reactor kinetics with delayed neutrons by Monte Carlo method

Jan Kyncl (1994)

Applications of Mathematics

In this paper, the linear problem of reactor kinetics with delayed neutrons is studied whose formulation is based on the integral transport equation. Besides the proof of existence and uniqueness of the solution, a special random process and random variables for numerical elaboration of the problem by Monte Carlo method are presented. It is proved that these variables give an unbiased estimate of the solution and that their expectations and variances are finite.

On quenched and annealed critical curves of random pinning model with finite range correlations

Julien Poisat (2013)

Annales de l'I.H.P. Probabilités et statistiques

This paper focuses on directed polymers pinned at a disordered and correlated interface. We assume that the disorder sequence is a q -order moving average and show that the critical curve of the annealed model can be expressed in terms of the Perron–Frobenius eigenvalue of an explicit transfer matrix, which generalizes the annealed bound of the critical curve for i.i.d. disorder. We provide explicit values of the annealed critical curve for q = 1 and q = 2 and a weak disorder asymptotic in the general case....

On some parabolic-elliptic system with self-similar pressure term

Robert Stańczy (2006)

Banach Center Publications

A priori estimates for solutions of a system describing the interaction of gravitationally attracting particles with a self-similar pressure term are proved. The presented theory covers the case of the model with diffusions that obey either Fermi-Dirac statistics or a polytropic one.

On stationary kinetic systems of Boltzmann type and their fluid limits

Leif Arkeryd (2004)

Banach Center Publications

The first part reviews some recent ideas and L¹-existence results for non-linear stationary equations of Boltzmann type in a bounded domain in ℝⁿ and far from global Maxwellian equilibrium. That is an area not covered by the DiPerna and P. L. Lions methods for the time-dependent Boltzmann equation from the late 1980-ies. The final part discusses the more classical perturbative case close to global equilibrium and corresponding small mean free path limits of fully non-linear stationary problems....

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