Search results for "NLO"
showing 10 items of 285 documents
Heat transfer in conducting and radiating bodies
1997
Abstract We introduce briefly some nonlocal models for heat transfer in conducting and radiating media. The goal is to give an idea of the general mathematical structure and related existence results for such models.
Time-dependent density-functional theory for strongly interacting electrons
2017
We consider an analytically solvable model of two interacting electrons that allows for the calculation of the exact exchange-correlation kernel of time-dependent density functional theory. This kernel, as well as the corresponding density response function, is studied in the limit of large repulsive interactions between the electrons and we give analytical results for these quantities as an asymptotic expansion in powers of the square root of the interaction strength. We find that in the strong interaction limit the three leading terms in the expansion of the kernel act instantaneously while memory terms only appear in the next orders. We further derive an alternative expansion for the ker…
AN HYPERBOLIC-PARABOLIC PREDATOR-PREY MODEL INVOLVING A VOLE POPULATION STRUCTURED IN AGE
2020
Abstract We prove existence and stability of entropy solutions for a predator-prey system consisting of an hyperbolic equation for predators and a parabolic-hyperbolic equation for preys. The preys' equation, which represents the evolution of a population of voles as in [2] , depends on time, t, age, a, and on a 2-dimensional space variable x, and it is supplemented by a nonlocal boundary condition at a = 0 . The drift term in the predators' equation depends nonlocally on the density of preys and the two equations are also coupled via classical source terms of Lotka-Volterra type, as in [4] . We establish existence of solutions by applying the vanishing viscosity method, and we prove stabil…
Porti e automazione: spunti in materia di responsabilità delle imprese di sbarco
2019
Lo studio si incentra sull'automazione delle operazioni portuali di imbarco e di sbarco, con particolare riferimento all'incidenza della tecnologia sul sistema di responsabilità degli attori del trasporto marittimo. Sarà trattata la normativa portuale, la governance, il sistema di protezione sociale dei lavoratori portuali e il regime giuridico dei terminal operator. La relazione tra attività totalmente automatizzata e infrastrutture marittime è analizzata nel contesto del diritto internazionale marittimo. The article focuses on the automatization of loading, stowing and unloading ports operations, from the point of view of the impact of the technologies on the system of liabilities of the …
Nonlocal Elastic-Damage Models
2014
A theory of nonlocal isotropic damage for elastic quasi-brittle materials is presented under the assumption of isothermal conditions and small deformations. Key ingredients of this theory are a self-adjoint (regularization) operator which transforms a local field into a related nonlocal one while preserves uniform fields and a free energy which depends on the strain and (linearly) on the nonlocal damage variable, as well as on an (scalar) internal variable accounting for the damage hardening. The relevant thermodynamic restrictions on the constitutive equations are obtained by means of two alternative procedures, one based on the principle of virtual power and the other on the concept of “n…
Contact with Nature as Essential to the Human Experience
2021
Human contact with nature is more important than ever before considering the global confinement brought about by the COVID-19 pandemic, the increased urbanization of society, and increased rates of mental disorders and threats to human well-being. This article conveys the importance of contact with nature from three perspectives: historical, sociocultural, and scientific. These perspectives convey the many ways in which contact with nature is essential to human life, the multiple ways in which this is expressed, and the broad range of benefits this has. The case for preserving the natural environment continues to be made in light of the dangers of climate change, the deleterious effects of …
Hitchhiker's guide to the fractional Sobolev spaces
2012
AbstractThis paper deals with the fractional Sobolev spaces Ws,p. We analyze the relations among some of their possible definitions and their role in the trace theory. We prove continuous and compact embeddings, investigating the problem of the extension domains and other regularity results.Most of the results we present here are probably well known to the experts, but we believe that our proofs are original and we do not make use of any interpolation techniques nor pass through the theory of Besov spaces. We also present some counterexamples in non-Lipschitz domains.
Solving fractional Schroedinger-type spectral problems: Cauchy oscillator and Cauchy well
2014
This paper is a direct offspring of Ref. [J. Math. Phys. 54, 072103, (2013)] where basic tenets of the nonlocally induced random and quantum dynamics were analyzed. A number of mentions was maid with respect to various inconsistencies and faulty statements omnipresent in the literature devoted to so-called fractional quantum mechanics spectral problems. Presently, we give a decisive computer-assisted proof, for an exemplary finite and ultimately infinite Cauchy well problem, that spectral solutions proposed so far were plainly wrong. As a constructive input, we provide an explicit spectral solution of the finite Cauchy well. The infinite well emerges as a limiting case in a sequence of deep…
Brodsky-Lepage-Mackenzie scale for the pion transition form factor
2002
The next-to-leading order (NLO) Brodsky-Lepage-Mackenzie (BLM) scale for the pion transition form factor is determined. To achieve that, a consistent calculation up to ${n}_{f}$-proportional next-to-next-to-leading order contributions to both the hard-scattering amplitude and the perturbatively calculable part of the pion distribution amplitude is performed. By combining and matching the results obtained for these two amplitudes, a proper cancellation of collinear singularities is established and the ${\ensuremath{\gamma}}_{5}$ ambiguity problem (related to the use of the dimensional regularization method) is resolved by using the naive-${\ensuremath{\gamma}}_{5}$ as well as the 't Hooft--V…
WZ Production in Association with Two Jets at Next-to-Leading Order in QCD
2013
We report on the calculation of W-+/- Zjj production with leptonic decays at hadron-hadron colliders at next-to-leading order in QCD. These processes are important both to test the quartic gauge couplings of the standard model and because they constitute relevant backgrounds to beyond standard model physics searches. Our results show that the next-to-leading order corrections reduce significantly the scale uncertainties and have a nontrivial phase space dependence.