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A Collaborative Effort Between Caribbean States for Tsunami Numerical Modeling: Case Study CaribeWave15
(Pure and Applied Geophysics vol.175 no.2 1405-1428 2017, 2017)Historical records have shown that tsunami have affected the Caribbean region in the past. However infrequent, recent studies have demonstrated that they pose a latent hazard for countries within this basin. The Hazard ... -
A methane sink in the Central American high elevation páramo: Topographic, soil moisture and vegetation effects
(Elsevier B.V., 2020-03-15)Methane (CH4) is a strong greenhouse gas with a global warming potential 23 times larger than that of carbon dioxide. Characterizing ecosystems as either sources or sinks for methane and their magnitudes informs on biosphere ... -
A mixed virtual element method for a pseudostress-based formulation of linear elasticity
(Elsevier B.V., 2019)In this paper we introduce and analyze a mixed virtual element method (mixed-VEM) for a pseudostress-displacement formulation of the linear elasticity problem with non homogeneous Dirichlet boundary conditions. We follow ... -
A mixed virtual element method for quasi-Newtonian stokes flows
(SIAM, 2018)In this paper we introduce and analyze a virtual element method (VEM) for an augmented mixed variational formulation of a class of nonlinear Stokes models arising in quasi-Newtonian fluids. While the original unknowns are ... -
A mixed virtual element method for the boussinesq problem on polygonal meshes
(Global Science Press, 2021)In this work we introduce and analyze a mixed virtual element method (mixed-VEM) for the two-dimensional stationary Boussinesq problem. The continuous formulation is based on the introduction of a pseudostress tensor ... -
A New Hybrid of Serpocaulon (Polypodiaceae) from Costa Rica
(Bio One Research Evolved, 2013)A new hybrid Serpocaulon 3 sessilipinnum A. Rojas & J.M. Chaves is described. The new taxon has characters intermediate between S. fraxinifolium (Jacq.) A.R. Sm. and S. ptilorhizon (Christ) A.R. Sm., which are related ... -
A posteriori error analysis of a mixed virtual element method for a nonlinear Brinkman model of porous media flow
(Elsevier Ltd, 2020-06-25)In this paper we present an a posteriori error analysis of a mixed-VEM discretization for a nonlinear Brinkman model of porous media flow, which has been proposed by the authors in a previous work. Therein, the system ... -
A preliminary isotope-based evapotranspiration partitioningapproach for tropical Costa Rica
(John Wiley and Sons Ltd, 2021-07)Spatially and seasonally distributed information on transpiration (T) fluxes is limited in the tropics. Here, we applied a coupled isotope mass balance model to separate water fluxes of T and evapotranspiration (ET) from ... -
A Priori and a Posteriori Error Analyses of an Augmented HDG Method for a Class of Quasi-Newtonian Stokes Flows
(Springer, 2016-12)In a recent work we developed a new hybridizable discontinuous Galerkin (HDG) method for a class of nonlinear Stokes models arising in quasi-Newtonian fluids. The approach there uses the incompressibility condition to ... -
A priori and a posteriori error analyses of an HDG method for the Brinkman problem
(Elsevier, 2018-01-15)In this paper we introduce and analyze a hybridizable discontinuous Galerkin (HDG) method for the linear Brinkman model of porous media flow in two and three dimensions and with non-homogeneous Dirichlet boundary conditions. ... -
A RTk - P-k approximation for linear elasticity yielding a broken H(div) convergent postprocessed stress
(Universidad Nacional, Costa Rica, 2015)We present a non-standard mixed finite element method for the linear elasticity problem in R-n with non-homogeneous Dirichlet boundary conditions. More precisely, our approach is based on a simplified interpretation of the ... -
A study of the social perception of technology in public spaces in Alajuela Central Cantón, Costa Rica
(Institute of Electrical and Electronics Engineers Inc., 2019-08-20)The present work makes an analysis of the results of a study of the social perception of technology applied in the public spaces of the central canton of Alajuela, Costa Rica. This study is of a non-probabilistic type, ... -
ABP desde las trincheras: un caso de estudio en la enseñanza de la Ingeniería de Sistemas
(Alborg University Denmark, 2017)Este trabajo describe la implementación de la filosofía ABP (Aprendizaje basado en problemas), desde una perspectiva bottom-up, en la Escuela de Informática de la Universidad Nacional (UNA), Costa Rica. La implementación ... -
Academic Emotions in Programming Learning: Women’s Impact on the Software Sector
(Springer Verlag, 2019)This document presents an analysis based on a systematic review carried out on the most recognized topics related to academic emotions in the different mechanisms of research and emotional evaluation, trying to ... -
Actitud del docente de educación secundaria ante la historia de las matemáticas y su implementación como recurso didáctico en las regiones educativas Heredia y San José Central
(Universidad Nacional (Costa Rica), 2020)Describe la actitud, la formación y el uso de la historia de las matemáticas como recurso didáctico que manifiestan los docentes en educación secundaria de las regiones educativas Heredia y San José Central. La investigación ... -
Adaptación del método de descarga de arco voltaico para la síntesis de nanotubos de carbono de pared simple
(Universidad Nacional (Costa Rica), 2009-11)Los nanotubos de carbono fueron descubiertos por el físico japonés Sumio lijima en 1991. Sus propiedades físicas y químicas catalogadas como extraordinarias, siguen demostrando gran potencial en multitud de campos. Los ... -
Addition of nanosilicas with different silanol content to thermoplastic polyurethane adhesives
(Elsevier, 2005-08-15)Three nanosilicas with different silanol contents were prepared by treatment of hydrophilic fumed silica with dimethyldichlorosilane. This treatment reduced the silanol content and produced the particle agglomeration of ... -
An approach to rheological and electrokinetic behaviour of lipidic vesicles covered with chitosan biopolymer
(Elsevier, 2008)The rheological and electrokinetic properties of soybean lecithin vesicles prepared from concentrated soy lecithin dispersions (250 g/L) obtained by slow swelling under shear conditions and mixed with chitosan biopolymer ... -
An evaluation of variables affecting the stability and performance of down-flow anaerobic fixed bed reactors treating piggery wastewater
(Taylor & Francis, 2006)The influence of the most important variables on the stability and performance of down-flow anaerobic fixed bed reactors treating piggery wastewater after primary sedimentation was evaluated at HRT in the range of 1-6 d ... -
Analysis of an augmented pseudostress-based mixed formulation for a nonlinear Brinkman model of porous media flow
(Elsevier, 2015)In this paper we introduce and analyze an augmented mixed finite element method for the two-dimensional nonlinear Brinkman model of porous media flow with mixed boundary conditions. More precisely, we extend a previous ...