Search results for "equation"
showing 10 items of 4219 documents
Time-domain effective-one-body gravitational waveforms for coalescing compact binaries with nonprecessing spins, tides and self-spin effects
2018
We present TEOBResumS, a new effective-one-body (EOB) waveform model for nonprecessing (spin-aligned) and tidally interacting compact binaries.Spin-orbit and spin-spin effects are blended together by making use of the concept of centrifugal EOB radius. The point-mass sector through merger and ringdown is informed by numerical relativity (NR) simulations of binary black holes (BBH) computed with the SpEC and BAM codes. An improved, NR-based phenomenological description of the postmerger waveform is developed.The tidal sector of TEOBResumS describes the dynamics of neutron star binaries up to merger and incorporates a resummed attractive potential motivated by recent advances in the post-Newt…
Non-standard Problems in an Ordinary Differential Equations Course
2018
International audience; We report first results from a teaching intervention in an ordinary differential equations (ODEs) course for engineering students. Our aim is to challenge traditional approaches to teaching of Existence and Uniqueness Theorems (EUTs) through the design of problems that students cannot solve by applying well-rehearsed techniques or familiar methods. We analyse how the use of nonstandard problems contributes to the development of students' conceptual understanding of EUTs and ODEs.
Generalized heat equation and transitions between different heat-transport regimes in narrow stripes
2019
Abstract In the framework of weakly nonlocal thermodynamic theory, in this paper we derive a nonlocal and nonlinear heat-transport equation beyond the Fourier law by means of thermodynamic considerations in agreement with the second law. The obtained equation describes the transitions among different heat-transport regimes. The stability of the solution of that equation is also analyzed in a special case.
Effective charge from lattice QCD
2020
Using lattice configurations for quantum chromodynamics (QCD) generated with three domain-wall fermions at a physical pion mass, we obtain a parameter-free prediction of QCD's renormalisation-group-invariant process-independent effective charge, $\hat\alpha(k^2)$. Owing to the dynamical breaking of scale invariance, evident in the emergence of a gluon mass-scale, this coupling saturates at infrared momenta: $\hat\alpha(0)/\pi=0.97(4)$. Amongst other things: $\hat\alpha(k^2)$ is almost identical to the process-dependent (PD) effective charge defined via the Bjorken sum rule; and also that PD charge which, employed in the one-loop evolution equations, delivers agreement between pion parton di…
Influencia de la percepción multisensorial en la experiencia, satisfacción y felicidad del consumidor de música en vivo. Efecto moderador de la disca…
2023
La presente tesis doctoral se centra, a lo largo de cinco capítulos, en analizar la relación de la percepción multisensorial y la experiencia del consumidor en el contexto de la música en vivo. Además, estudia el efecto de esta última en la satisfacción, la felicidad subjetiva y la intención de compra, para personas con y sin discapacidad. El primer capítulo describe, por una parte, el contexto de la música y, por otra, aborda cuestiones relativas a la discapacidad de los consumidores. En el segundo capítulo se afronta la revisión de la literatura sobre: percepción multisensorial y experiencia de consumo. El tercer capítulo presenta en primera instancia el objetivo general y los objetivos e…
Stieltjes Differential Inclusions with Periodic Boundary Conditions without Upper Semicontinuity
2021
We are studying first order differential inclusions with periodic boundary conditions where the Stieltjes derivative with respect to a left-continuous non-decreasing function replaces the classical derivative. The involved set-valued mapping is not assumed to have compact and convex values, nor to be upper semicontinuous concerning the second argument everywhere, as in other related works. A condition involving the contingent derivative relative to the non-decreasing function (recently introduced and applied to initial value problems by R.L. Pouso, I.M. Marquez Albes, and J. Rodriguez-Lopez) is imposed on the set where the upper semicontinuity and the assumption to have compact convex value…
An appraisal of the fit of a cognitive behavioural model of headache in University students
2018
The aim of this study was to evaluate the fit of a cognitive behavioural model of headache in the population of University students, from Córdoba,Argentina. The direct and indirect contributions to pain intensity of control beliefs, beliefs and thoughts about pain and coping strategies weredetermined, as were the direct contributions of pain behaviours and disability. The sample was comprised of 382 students of both genders fromseveral Universities. Multiple instruments were administered to measure the variables proposed in the cognitive behavioural model of headachefollowed by a descriptive and exploratory analysis of the data. Structural equation modelling was used and revealed an accepta…
Age-Structured Human Population Dynamics
2006
ABSTRACT A von Foerster-McKendrick model to study age-structured human population dynamics is presented in this paper. Forecasts of population density (population per age unit) depending on ages are possible using this model. The model consists of a quasi-linear first order partial differential equation for the dynamics of population density per age-unit (except for the zero-age), a boundary condition for the births flow at zero-age, and an initial condition for the population density at the initial instant. A general solution independent of the particular human-system under study is obtained based on some hypotheses about the mathematical structure of its input variables. The model has bee…
Pupil's ecological reasoning with help of modeling tool
2006
Ecological concepts, and in particular population dynamics, has been found to be among the most difficult topics in biology. Some researchers pointed to students' relatively weak mathematical background as the main source of learning difficulties. This paper reports on an investigation of pupil's (n=73) reasoning about the ecological phenomena by using an iconic modelling tool, WorldMaker. The simulations eliminated the need for understanding of mathematical equations, and made the ecological concepts much more accessible to some children. However, many of the pupils reasoned from an anthropocentric perspective that obstructed their ability to predict ecological phenomena which requires sys…
Influence of geometric variations on LV activation times: A study on an atlas-based virtual population
2010
We present the fully automated pipeline we have developed to obtain electrophysiological simulations of the heart on a large atlas-based virtual population. This virtual population was generated from a statistical model of left ventricular geometry, represented by a surface model. Correspondence between tetrahedralized volumetric meshes was obtained using Thin Plate Spline warps. Simulations are based on the fast solving of Eikonal equations, and stimulation sites correspond to physiological activation. We report variations of total activation time introduced by geometry, as well as variations in the location of last activation. The obtained results suggest that the total activation time ha…