Search results for "online"
showing 10 items of 4526 documents
Online Learning Environments, Scientific Argumentation, and 21st Century Skills
2019
A workshop held at the National Academies in the United States in 2007 highlighted five broad categories of skills that appear valuable across a range of jobs for people working in modern global economies. Engaging students in scientific argumentation can support the development of these 21st century skills. Unfortunately, opportunities are rare in typical classrooms for students to learn how to engage in scientific argumentation. Over the past ten years several online environments have been developed to support students engaging with one another in scientific argumentation. This paper considers how engaging students in scientific argumentation through the activity structures and scripts in…
Families of piecewise linear maps with constant Lyapunov exponent
2012
We consider families of piecewise linear maps in which the moduli of the two slopes take different values. In some parameter regions, despite the variations in the dynamics, the Lyapunov exponent and the topological entropy remain constant. We provide numerical evidence of this fact and we prove it analytically for some special cases. The mechanism is very different from that of the logistic map and we conjecture that the Lyapunov plateaus reflect arithmetic relations between the slopes.
Localization of 2D Cameras in a Known Environment Using Direct 2D-3D Registration
2014
International audience; In this paper we propose a robust and direct 2D-to- 3D registration method for localizing 2D cameras in a known 3D environment. Although the 3D environment is known, localizing the cameras remains a challenging problem that is particularly undermined by the unknown 2D-3D correspondences, outliers, scale ambiguities and occlusions. Once the cameras are localized, the Structure-from-Motion reconstruction obtained from image correspondences is refined by means of a constrained nonlinear optimization that benefits from the knowledge of the scene. We also propose a common optimization framework for both localization and refinement steps in which projection errors in one v…
Multi-parameters rational solutions to the mKdV equation
2021
N-order solutions to the modified Korteweg-de Vries (mKdV) equation are given in terms of a quotient of two wronskians of order N depending on 2N real parameters. When one of these parameters goes to 0, we succeed to get for each positive integer N , rational solutions as a quotient of polynomials in x and t depending on 2N real parameters. We construct explicit expressions of these rational solutions for orders N = 1 until N = 6.
Quantization of Poisson Lie Groups and Applications
1996
LetG be a connected Poisson-Lie group. We discuss aspects of the question of Drinfel'd:can G be quantized? and give some answers. WhenG is semisimple (a case where the answer isyes), we introduce quantizable Poisson subalgebras ofC ∞(G), related to harmonic analysis onG; they are a generalization of F.R.T. models of quantum groups, and provide new examples of quantized Poisson algebras.
A computational method for studying the relation between alternative splicing and DNA methylation.
2015
Alternative splicing is an important mechanism in eukaryotes that expands the transcriptome and proteome significantly. It plays an important role in a number of biological processes. Understanding its regulation is hence an important challenge. Recently, increasing evidence has been collected that supports an involvement of intragenic DNA methylation in the regulation of alternative splicing. The exact mechanisms of regulation, however, are largely unknown, and speculated to be complex: different methylation profiles might exist, each of which could be associated with a different regulation mechanism. We present a computational technique that is able to determine such stable methylation pa…
Condiciones generales de la contratación en las apuestas online
2022
En el presente trabajo su autor analiza las condiciones generales de la contratación en un ámbito muy concreto que son las apuestas online. Para ello, se procede al estudio de las resoluciones judiciales en las que se han declarado nulas por abusivas determinas cláusulas; a modo de ejemplo se pueden enunciar: aquellas que permiten que sea la casa de apuestas la que decide cuando cerrar o suspender las cuentas de los usuarios; o aquellas que permiten anular la apuesta alegando errores en la determinación de la cuota. A partir de las conclusiones obtenidas, se procede a analizar las condiciones generales de la contratación de dos casas de apuestas como son Sportium y Bet365, con el fin último…
Servicios de intermediación en línea en Europa : diseño de un sistema específico de solución de controversias
2021
Este trabajo analiza el sistema de solución de controversias específicamente diseñado, con la introducción de alternativas a la jurisdicción, en el Reglamento (UE) 2019/1150 sobre el fomento de la equidad y la transparencia para los usuarios profesionales de servicios de intermediación en línea, que ha entrado recientemente en vigor.
Roadmap on optical rogue waves and extreme events
2016
Nail Akhmediev et al. ; 38 págs.; 28 figs.
Adaptive synchronization of master-slave systems with mixed neutral and discrete time-delays and nonlinear perturbations
2011
This paper investigates the delay-dependent adaptive synchronization problem of the master and slave structure of linear systems with both constant neutral and time-varying discrete time-delays and nonlinear perturbations based on the Barbalat lemma and matching conditions. An adaption law which includes the master-slave parameters is obtained by using the Lyapunov functional method and inequality techniques to synchronize the master-slave systems without the knowledge of upper bounds of perturbation terms. Particularly, it is shown that the synchronization speed can be controlled by adjusting the update gain of the synchronization signal. A numerical example has been given to show the effe…