Now showing items 78-97 of 126

• #### On a Boltzmann equation for Compton scattering, from non relativistic electrons at low density. ﻿

(2018-08-15)
A Boltzmann equation, used to describe the Compton scattering in the non-relativistic limit is considered. A truncation of the very singular redistribution function is introduced and justified. The existence of weak solutions ...
• #### On a system of equations for the normal fluid - condensate interaction in a Bose gas ﻿

(2018-03-27)
The existence of global solutions for a system of differential equations is proved, and some of their properties are described. The system involves a kinetic equation for quantum particles. It is a simplified version of ...
• #### On intersection cohomology with torus actions of complexity one ﻿

(Revista Matemática Completense, 2017-05-20)
The purpose of this article is to investigate the intersection cohomology for algebraic varieties with torus action. Given an algebraic torus T, one of our result determines the intersection cohomology Betti numbers of ...
• #### On Lipschitz rigidity of complex analytic sets ﻿

(The Journal of Geometric Analysis, 2019-02-26)
We prove that any complex analytic set in $\mathbb{C}^n$ which is Lipschitz normally embedded at infinity and has tangent cone at infinity that is a linear subspace of $\mathbb{C}^n$ must be an affine linear subspace of ...
• #### On the generalized Nash problem for smooth germs and adjacencies of curve singularities ﻿

In this paper we explore the generalized Nash problem for arcs on a germ of smooth surface: given two prime divisors above its special point, to determine whether the arc space of one of them is included in the arc space ...
• #### On the geometry of strongly flat semigroups and their generalizations ﻿

(2018-09-18)
Our goal is to convince the readers that the theory of complex normal surface singularities can be a powerful tool in the study of numerical semigroups, and, in the same time, a very rich source of interesting affine and ...
• #### On the merits of sparse surrogates for global sensitivity analysis of multi-scale nonlinear problems: Application to turbulence and fire-spotting model in wildland fire simulators ﻿

(Communications in Nonlinear Science and Numerical Simulation, 2019-02)
Many nonlinear phenomena, whose numerical simulation is not straightforward, depend on a set of parameters in a way which is not easy to predict beforehand. Wildland fires in presence of strong winds fall into this category, ...
• #### On the propagation of nonlinear transients of temperature and pore pressure in a thin porous boundary layer between two rocks. ﻿

(Journal of Hydrology, 2019)
The dynamics of transients of fluid-rock temperature, pore pressure, pollutants in porous rocks are of vivid interest for fundamental problems in hydrological, volcanic, hydrocarbon systems, deep oil drilling. This can ...
• #### On Zariski’s multiplicity problem at infinity ﻿

(Proceedings of the American Mathematical Society, 2018-08-14)
We address a metric version of Zariski's multiplicity conjecture at infinity that says that two complex algebraic affine sets which are bi-Lipschitz homeomorphic at infinity must have the same degree. More specifically, ...
• #### Perverse sheaves on semi-abelian varieties -- a survey of properties and applications ﻿

(European Journal of Mathematics, 2019-05)
We survey recent developments in the study of perverse sheaves on semi-abelian varieties. As concrete applications, we discuss various restrictions on the homotopy type of complex algebraic manifolds (expressed in terms ...
• #### A proof of the differentiable invariance of the multiplicity using spherical blowing-up ﻿

(Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas, 2018-04-21)
In this paper we use some properties of spherical blowing-up to give an alternative and more geometric proof of Gau-Lipman Theorem about the differentiable invariance of the multiplicity of complex analytic sets. Moreover, ...
• #### A proof of the integral identity conjecture, II ﻿

(Comptes Rendus Mathematique, 2017-10-31)
In this note, using Cluckers-Loeser’s theory of motivic integration, we prove the integral identity conjecture with framework a localized Grothendieck ring of varieties over an arbitrary base field of characteristic zero.
• #### Quasi-probability Approach for Modelling Local Extinction and Counter-gradient in Turbulent Premixed Combustion ﻿

(Proceedings/Extended Abstract Book (6 pages) of the XLI Meeting of the Italian Section of the Combustion Institute, 2018-05-23)
In opposition to standard probability distributions, quasi-probability distributions can have negative values which highlight nonclassical properties of the corresponding system. In quantum mechanics, such negative values ...
• #### Random diffusivity from stochastic equations: comparison of two models for Brownian yet non-Gaussian diffusion ﻿

(New Journal of Physics, 2018-04)
A considerable number of systems have recently been reported in which Brownian yet non-Gaussian dynamics was observed. These are processes characterised by a linear growth in time of the mean squared displacement, yet the ...
• #### RandomFront 2.3 A physical parametrisation of fire-spotting for operational fire spread models: Implementation in WRF-Sfire and response analysis with LSFire+ ﻿

(Geoscientific Model Development, 2018-12)
Fire-spotting is often responsible for a dangerous flare up in the wildfire and causes secondary ignitions isolated from the primary fire zone leading to perilous situations. The main aim of the present research to provide ...
• #### Reduced description method in the kinetic theory of Brownian motion with active fluctuations ﻿

(Journal of Physics A: Mathematical and Theoretical, 2019-09-01)
We develop a microscopic approach to the kinetic theory of many-particle systems with dissipative and potential interactions in presence of active fluctuations. The approach is based on a generalization of Bogolyubov–Peletminskii ...
• #### Representation of surface homeomorphisms by tête-à-tête graphs ﻿

(2017-06-21)
We use tête-à-tête graphs as defined by N. A'campo and extended versions to codify all periodic mapping classes of an orientable surface with non-empty boundary, improving work of N. A'Campo and C. Graf. We also introduce ...
• #### Restoring property of the Michelson-Sivashinsky equation ﻿

(Combustion Science and Technology, 2019)
In this paper we propose a derivation of the Michelson-Sivashinsky (MS) equation that is based on front propagation only, in opposition to the classical derivation based also on the flow field. Hence, the characteristics ...
• #### Right unimodal and bimodal singularities in positive characteristic ﻿

(International Mathematics Research Notices, 2017-08-07)
The problem of classification of real and complex singularities was initiated by Arnol'd in the sixties who classified simple, unimodal and bimodal singularities w.r.t. right equivalence. The classification of simple ...
• #### The role of the environment in front propagation ﻿

(Proceedings of the 18th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2018 July 9–14, 2018, 2018-07-09)
In this work we study the role of a complex environment in the propagation of a front with curvature-dependent speed. The motion of the front is split into a drifting part and a fluctuating part. The drifting part is ...