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A study on congruency effects and numerical distance in fraction comparison by expert undergraduate students
(Frontiers Media, 2020)
School mathematics comprises a diversity of concepts whose cognitive complexity is still poorly understood, a chief example being fractions. These are typically taught in middle school, but many students fail to master ...
Canopy gap structure as an indicator of intact, old-growth temperate rainforests in the Valdivian ecoregion
(MDPI, 2021)
Forest degradation continues to increase globally, threatening biodiversity and the survival
of species. In this context, identifying intact, old-growth forest stands is both urgent and vital to
ensure their existence ...
An approximation to the informal-formal wage gap in Colombia 2008-2012
(Universidad del RosarioFacultad de Economía, 2013)
This document provides recent evidence about the persistency of wage gaps between formal and informal workers in Colombia by using a non-parametric method proposed by Ñopo (2008a). Over a rich dataset at a household level ...
Enhanced gap fraction extraction from hemispherical photography
(Institute of Electrical and Electronics Engineers, 2015-03)
Canopy structure can be estimated using gap fraction (GF) data, which can be directly measured with hemispherical photography. However, GF data accuracy is affected by sunlit canopy, multiple scattering, vignetting, blooming, ...
Model-based local thresholding for canopy hemispherical photography
(National Research Council Canada-NRC Research Press, 2018-07)
Canopy hemispherical photography (HP) is widely used to estimate forest structural variables. To achieve good results with HP, a classification algorithm is needed to produce binary images to accurately estimate the gap ...
Interaction between non-Bragg band gaps in ID metamaterial photonic crystals
(Optical Society of America, 2006-12)
We consider periodic multilayers combining ordinary positive index materials and dispersive metamaterials with negative index in some frequency range. These structures can exhibit photonic band gaps which, in contrast with ...
An improved estimate of leaf area index based on the histogram analysis of hemispherical photographs
(ELSEVIER SCIENCE BV, 2009)
Leaf area index (LAI) is a key parameter that affects the surface fluxes of energy, mass, and momentum over vegetated lands, but observational measurements are scarce, especially in remote areas with complex canopy structure. ...
A short FE implementation for a 2d homogeneous Dirichlet problem of a fractional Laplacian
(Pergamon-Elsevier Science Ltd, 2017-08)
In Acosta etal. (2017), a complete n-dimensional finite element analysis of the homogeneous Dirichlet problem associated to a fractional Laplacian was presented. Here we provide a comprehensive and simple 2D MATLAB ® finite ...