Search results for "harmonic"

Monotonicity Formulas for Harmonic Functions in RCD(0,N) Spaces

2023

We generalize to the RCD(0,N) setting a family of monotonicity formulas by Colding and Minicozzi for positive harmonic functions in Riemannian manifolds with nonnegative Ricci curvature. Rigidity and almost rigidity statements are also proven, the second appearing to be new even in the smooth setting. Motivated by the recent work in Agostiniani et al. (Invent. Math. 222(3):1033–1101, 2020), we also introduce the notion of electrostatic potential in RCD spaces, which also satisfies our monotonicity formulas. Our arguments are mainly based on new estimates for harmonic functions in RCD(K,N) spaces and on a new functional version of the ‘(almost) outer volume cone implies (almost) outer metric…

Investigations of methyl lactate in the presence of reverse micelles by vibrational spectroscopy and circular dichroism

2012

Abstract The FT-IR and vibrational circular dichroism (VCD) spectra of ( S )- and -( R )-methyl lactate have been recorded for neat samples and at various concentrations in CCl 4 and DMSO solutions. These spectra are used to analyse the FT-IR and VCD spectra of methyl lactates in presence of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) in CCl 4 , where the surfactant molecules are known to form reverse micelles. Some tendency of methyl lactate to interact with AOT micellar aggregates is observed, but not as well defined as previously observed for dimethyl tartrate in analogous circumstances. Besides, near infrared (NIR) absorption and VCD data have been obtained for most of the above system…

Riferibilità dei contatori statici di energia reattiva in presenza di armoniche. Evoluzione normativa e prove sperimentali

2013

Traceability of static reactive energy meters in the presence of harmonics: theoretical considerations and a DAQ-based reference meter

2013

This paper deals with some problems related to the measurements traceability with static meters for reactive energy. These problems arise when the meters operate in the presence of harmonics, which can negatively affect their performances, depending on implemented metric. The paper analyzes the problem in the light of both in-force and draft standards, from the viewpoint of the performances of both commercial meters and reference standard instruments. The analysis is supported by some experimental tests, which are carried out by means of a reference meter, based on data acquisition boards, which can be used in both sinusoidal and distorted conditions.

On the calibration of reactive energy meters under non sinusoidal conditions

2009

This paper is focused on the problems related to the calibration of the reactive energy meters on the place of installation of the electricity meter (on-site), using the load of the same electrical system. In the presence of harmonic distortion, the behaviour of the meters can go out of the limits imposed by the theoretical calibration curve depending on the metric used by both reference standard meters and meters under test.

Correlated Event-by-Event Fluctuations of Flow Harmonics in Pb-Pb Collisions at √sNN = 2.76 TeV

2016

We report the measurements of correlations between event-by-event fluctuations of amplitudes of anisotropic flow harmonics in nucleus-nucleus collisions, obtained for the first time using a new analysis method based on multiparticle cumulants in mixed harmonics. This novel method is robust against systematic biases originating from nonflow effects and by construction any dependence on symmetry planes is eliminated. We demonstrate that correlations of flow harmonics exhibit a better sensitivity to medium properties than the individual flow harmonics. The new measurements are performed in Pb-Pb collisions at the center-of-mass energy per nucleon pair of √=2.76  TeV sNN p ¼ 2.76 TeV by the ALI…

Biomechanical analysis of Ascending Thoracic Aortic Aneurysm (ATAA)

2021

According to the reports of the World Health Organisation (WHO), cardiovascular diseases are the number one cause of death worldwide. Specifically, arterial disease and degeneration are the major reasons for cardiovascular death and disability. Because these diseases are dependent on the changes of the mechanical properties of the arterial wall, it is very important to know as much as possible about the structural composition of arteries. The human aorta is the biggest artery in the body and consists of three main parts, ascending aorta, aortic arch and descending aorta. The walls of the arteries consist of three layers, the intima, media and adventitia, where each of the layers has differe…

Spherical harmonic expansion of fundamental solutions and their derivatives for homogenous elliptic operators

2017

In this work, a unified scheme for computing the fundamental solutions of a three-dimensional homogeneous elliptic partial differential operator is presented. The scheme is based on the Rayleigh expansion and on the Fourier representation of a homogeneous function. The scheme has the advantage of expressing the fundamental solutions and their derivatives up to the desired order without any term-by-term differentiation. Moreover, the coefficients of the series need to be computed only once, thus making the presented scheme attractive for numerical implementation. The scheme is employed to compute the fundamental solution of isotropic elasticity showing that the spherical harmonics expansions…

Rungen lause ja sovelluksia inversio-ongelmiin

2018

Analysis and reconstruction in stages of the design and construction process of the old and new basilica of S. Peter in Vatican, and its surroundings

2020

Resumen 1. Objetivos El objetivo general de esta Tesis Doctoral es reconstruir el proceso de diseño y construcción de la antigua y nueva basílica de San Pedro en el Vaticano, y de su entorno cercano. De forma complementaria, se reconstruye la evolución de la trama urbana del área del Vaticano, desde su origen hasta la actualidad. La reconstrucción del proceso de diseño y construcción se realizará de forma descriptiva y, especialmente, de forma gráfica. Los planos se realizarán con gran detalle, a escala y con gran precisión, utilizando las más avanzadas herramientas de dibujo digital. La reconstrucción de las diferentes etapas del proceso de diseño y construcción de la antigua basílica se r…