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The transformation of dl limonene (mixture of d- and l-form ~ 1:1) that came from the pyrolysis of scrap tires rubber was studied using four heteropolyacid catalysts (H3PW12O40, H3PMo12O40, H4SiW12O40 and H4PMo11VO40) supported on Q-10, SBA-15, MCM-41, and KIT-6. The catalyst activity was measured using a py/GC/FID under a nitrogen atmosphere. The active phase and support were characterized using various technical methods (XRD, Raman, TEM, N2 adsorption–desorption, NH3-TPD, and py-FTIR). The highest weak acidity and largest number of Lewis acid sites promoted the conversion of dl limonene. The isomerization reactions seemed to be more favored than disproportionation reactions. The p-cymene yield was favored, with a high weak acidity and high Lewis/Bronsted acid sites ratio. Moreover, the results show that the use of amorphous support with a higher pore size seems to promote the conversion of dl limonene and the production of p-cymene. HPA-based catalysts with Si are more favorable for converting dl limonene to p-cymene than those with P. For the HPA-based catalysts with P, the highest acidity favors the highest conversion, especially the Lewis acid sites. In this study, the isomerization reactions seem to be more favored than disproportionation reactions.

espanolEn este trabajo se estudia el comportamiento mecanico del alabe de una turbina eolica, analizando el impacto del diseno del alabe en la cantidad de energia generada, y su respuesta estructural en funcion de las fuerzas inducidas por el flujo de aire. Para estudiar la relacion entre las fuerzas del flujo, los desplazamientos y esfuerzos provocados en la estructura, utilizamos un modelo de interaccion fluido estructura (FSI). La estructura del alabe se disena por medio de la teoria del momento y el elemento de pala (BEM), tomando como puntos de partida constantes referentes al viento (velocidad, densidad, Reynolds) y la seleccion de un perfil recomendado por la NACA, RISO, DU o NREL. Posteriormente, se efectua el mismo procedimiento para un perfil disenado mediante teorias de desempeno. Teniendo los resultados de estos dos tipos de alabes, se realiza una comparacion de los esfuerzos y desplazamientos debidos a las variaciones entre el perfil disenado y el perfil seleccionado, estudiando como esta variacion afecta la energia generada de la turbina y su integridad estructural. EnglishIn this work the mechanical behavior of the blade of a wind turbine is studied, analyzing the impact of the design of the blade on the amount of energy generated, and its structural response as a function of the stresses induced by the air flow. In order to study the relationship between flow forces, deformations and stresses induced in the structure, a Fluid Structure Interaction (FSI) model was used. The blade structure is designed using blade element momentum theory (BEM), taking constant properties related to the wind (speed, density, Reynolds), and the selection of a profile recommended by NACA, RISO, DU or NREL. Then, the same procedure is used for a profile designed using performance theories. Having these results for both types of blades, a comparison of the stresses and deformations due to the variations between the designed profile and the selected profile was made, analyzing the effects on the generated energy and the structural integrity of the turbine.

En un entorno turbulento y cambiante, las empresas buscan constantemente la manera de desarrollar nuevas estrategiasque les permita diferenciarse de la competencia y a su vez maximizar sus resultados económicos, para este caso medido en aumentode ventas nacionales y exportaciones.Toda empresa sin importar su tamaño o sector a nivel interno posee unos recursos y capacidades específicos, los cuales al seridentificados correctamente pueden potencializar la obtención de mejores resultados de la empresa a nivel económico.En el presente estudio a partir de la aplicación de un análisis empírico a las empresas de la industria colombiana incluidas en elcenso EDIT industria periodo 2011-2012 y con la utilización de herramientas estadísticas proporcionadas por el DANE.Se definieron como objeto de estudio los recursos de tipo Humano y las capacidades de Innovación y ordenar su gestión. Se tomóuna muestra de 2684 empresas y se obtuvo como. resultado de las estrategias usadas por las empresas del sector colombiano eneste periodo medido (2011-2012) que existe una fuerte correlacion entre la capacitación y formación de personal y los resultadosempresariales medidos en términos de ventas y exportaciones.

International audience; The catalytic reforming of pyrolytic oil comes from scrap tires rubber (STR) was studied using as catalyst three different heteropolyacids (HPA) supported on commercial silica (CARiACT Q-10); H3PW12O40 (HPW), H3PMo12O40 (HPMo) and H4PMo11VO40 (HPMoV). A specify attention was given to influence of acidity of catalysts (i.e. strength and acid site types i.e. Lewis and/or Brønsted) on the concentration of cymenes in the pyrolytic oil. The catalytic performance was evaluated in a fixed bed reactor at laboratory-scale equipped with two independent thermal zones; in the first, the STR pyrolysis takes place to produce volatile compounds which, consequently, were transformed in a catalytic zone. The resulting pyrolysis oil in each test was collected in two cooling traps and characterized by GC-MS and GC-FID for the identification and quantification of all aromatic compounds. The results showed a decrease on the pyrolytic oil yield when HPA based catalysts were used, which seems to be promoted by an higher number of Brønsted sites. It has reached an increase in the aromatic concentration, compared to the test without catalyst, of up to 140% for the Molybdenum-based catalysts and close to 89% for the Tungsten-based catalyst. The major compounds obtained were cymenes and its production was closely associated to the type and strength of acid sites. Thus, the highest amount of cymenes (mainly p-cymene) was obtained with the highest number of Lewis sites and the highest ratio of Lewis/Brønsted acid sites, i.e. Molybdenum-based catalysts. On the contrary, the lowest yields were obtained when the Tungsten-based catalyst was used associated to its higher number of Brønsted acid sites and its strong acidity that promote the cracking reactions.

(special issue HighRus2009). VAMDC; International audience

International audience; Advanced computing resources are requested by different interest groups, with the acceleration of digital transformation generated both by the pandemic and by the explosive increase in available information. Data centers have increased significantly over the past years to answer this demand but are now facing energy efficiency issues and performance requirements. Renewable energy is a promising solution by supplying local energy, but this power generation is reduced, intermittent, and requires changing how computation and data storage is managed. Edge/Fog computing is a promising solution to latency concerns proximity to data centers; however, this solution often extends existing clouds, imposing no specific principles to reduce energy and greenhouse emissions. This paper discusses challenges of a scalable architecture to support sustainable advanced information technology requirements inspired by the circular economy characteristics. The architecture has to keep rethinking computation, optimizing deployment, and regenerating energy.

(La,Sr)(Ti,Ni)O3 compounds have been characterized as air and hydrogen electrode for symmetrical Solid Oxide Cells. While the materials are thermomechanically compatible with 8YSZ electrolyte, the reactivity tests confirm the formation of an insulating pyrochlore La2Zr2O7, redhibitory for the electrochemical properties. Concerning the electrical behavior, a Ti/Ni = 50/50 ratio is the best option for high electrical conductivity in both air and hydrogen, in view of the targeted application as symmetric cell electrode. The electrochemical performance of La0.875Sr0.125Ti0.5Ni0.5O3 (25LSTN50) material is similar to the materials that have been proposed in literature for SOCs cathode and anode at the same time, but the polarization resistances are still higher than the state-of-the-art hydrogen or air electrodes of classical asymmetric cells.

The stability of La2xSr1-2xTi1-xNixO3-δ (LSTN) and La7x/4Sr1-7x/4Ti1-xNixO3-δ (25LSTN) materials in high temperature reducing conditions has been studied with a special focus on the Ni exsolution process for SOFC anode / SOEC cathode application. In a general way, LSTN and 25LSTN compounds are stable after treatments at 800 °C in air and wet reducing atmosphere. The low chemical expansion makes them compatible with a use in an electrochemical Solid Oxide Cell. Those materials are therefore useful for an application as symmetric oxide cell electrode or only hydrogen electrode. In situ Nickel exsolution is evidenced at 800 °C in Ar/H2(2%) but is limited by a slow kinetics and a higher temperature pre-reduction is preferred before a use as SOFC anode (SOEC cathode). Depending on the treatment, in situ reduction or pre-reduction (T>1000 °C), the compounds are not in the same thermodynamic equilibrium state.

We introduce the FunAndes database, a compilation of functional trait data for the Andean flora spanning six countries. FunAndes contains data on 24 traits across 2,694 taxa, for a total of 105,466 entries. The database features plant-morphological attributes including growth form, and leaf, stem, and wood traits measured at the species or individual level, together with geographic metadata (i.e., coordinates and elevation). FunAndes follows the field names, trait descriptions and units of measurement of the TRY database. It is currently available in open access in the FIGSHARE data repository, and will be part of TRY’s next release. Open access trait data from Andean plants will contribute to ecological research in the region, the most species rich terrestrial biodiversity hotspot.

Lattice structures are employed as lightweight sandwich cores, supports, or infill patterns of additive manufacturing (AM) components. As infill structures, the mechanical properties of AM parts are influenced by the infill pattern. In this work, we present the mechanical characterization of three commonly used infill patterns in AM, triangular, square, and hexagonal, and compare them with analytical and numerical models. Fused filament fabrication of polylactic acid (PLA) thermoplastic is used as the printing material for the compressive and tensile tests. First, a parametric analysis is performed by changing the infill density to obtain numerically and analytically the mechanical properties of the studied samples. Next, we compare the experimental results with numerical and analytical models and propose numerical correlations for high-density honeycombs. The stiffest infill pattern was the square, and the explanation is provided in detail. Also, there is a nonlinear correlation between density and the mechanical properties; however, the strongest part was not possible to determine with a significant statistical value. Finally, we propose simplified models for predicting the compressive and tensile response of AM PLA structures by considering the infill regions as homogenized structures.

International audience; This paper presents a descriptive study and scientometrics analysis to evaluate the incidence of the classification model of scientific journals Publindex in the behavior of Colombian journals in the area of Engineering and Technology. Qualitative and quantitative criteria were compiled, the production and contents of the journals were studied, and the national journals of the Engineering and Technology area were compared with the international journals of the same area. As a result, it is concluded that the implementation of the new categorization model served as a stimulus to boost the impact and improve the management of Colombian scientific journals in the study area. However, there is evidence of the need to implement models of editorial management and editorial policies (publication languages, periodicity, type of peer review, number of articles published, etc.) of international journals, and to rethink the classification model of scientific journals in Colombia incorporating guidelines that allow an objective evaluation based on the standardization and control of citation patterns.; En este artículo se presenta un estudio descriptivo y análisis cienciométrico para evaluar la incidencia del modelo de clasificación de revistas científicas de Publindex en el comportamiento del conjunto de revistas colombianas del área de Ingeniería y Tecnología. Se recopilaron criterios cualitativos y cuantitativos, se estudió la producción y contenidos de las revistas y se compararon las revistas nacionales del área de ingeniería y tecnología con las revistas internacionales de la misma área. Como resultado, se concluye que la implementación del nuevo modelo de categorización sirvió como estímulo para dinamizar la gestión e impacto, medido a través de indicadores de citación, de las revistas científicas colombianas del área de estudio. Sin embargo, se evidencia la necesidad de poner en práctica modelos de gestión editorial y políticas editoriales (idiomas de publicación, periodicidad, tipo de revisión, cantidad de artículos publicados, etc.) de revistas internacionales de referencia, y de replantear el modelo de clasificación de revistas científicas en Colombia incorporando directrices que permitan una evaluación objetiva a partir de la estandarización y control de patrones de citación.

With the scope to develop new electrode materials for Solid Oxide Cells, the (La,Sr)(Ti,Ni)O3-δ system has been studied by Pechini synthesis and heat-treatment in air. Only La2xSr1-2xTi1-xNixO3-δ (LSTN) and La7x/4Sr1-7x/4Ti1-xNixO3-δ (25LSTN) compounds can be prepared as pure phases after synthesis at the minimum temperature of 1000 °C for 12 h. All attempts to synthesize any materials of the La5x/3Sr1-5x/3Ti1-xNixO3-δ (33LSTN) and La3x/2Sr1-3x/2Ti1-xNixO3-δ (50LSTN) series were unsuccessful, due probably to a too high Ni3+ content that makes the structure unstable in those conditions. Substoichiometric La2x-0.05Sr1-2xTi1-xNixO3 (5ssLSTN) compounds exhibit also NiO impurity. For LTN50, the presence of an LaNiO3-type secondary phase is evidenced in the powder treated at 1300 °C for 12 h, present in higher amount for a synthesis at 1000 °C. LSTN (x

International audience; El presente trabajo de investigación tiene como objetivo analizar críticamente las representaciones del profesorado brasileño y colombiano sobre las políticas de evaluación externa implementadas en ambos países. Con tal propósito, se adoptó la perspectiva de los Estudios Históricos Comparados dentro de la matriz teórico-metodológica del Materialismo Histórico-Dialéctico. Se realizaron entrevistas semidirigidas con un total de 30 docentes que actuaban en diferentes áreas de seis escuelas públicas de Brasil y Colombia. Los resultados en ambos países evidenciaron que en torno a las pruebas externas existe una agenda orientada a homogeneizar la cotidianidad escolar con el fin de hacerla rentable desde el punto de vista económico, político e ideológico y en detrimento del profesional docente.

espanolEl presente articulo de investigacion tiene como objetivo analizar criticamente las politicas de evaluacion externa implementadas en Colombia y Brasil, en el contexto de la sociedad capitalista. Con base en este interes, se analizaron documentos oficiales y legales, adoptando la perspectiva de los Estudios Historicos Comparados dentro de la matriz teorico-metodologica del Materialismo Historico-Dialectico. Los resultados de investigacion demostraron que organismos internacionales al servicio del capital, como el Banco Mundial, ejercen influencia sobre las politicas de evaluacion de ambos paises mediante las ideologias del merito y la gestiogracia , que se refleja con la aplicacion de examenes estandarizados, la disposicion de indicadores de calidad y la organizacion de un sistema de responsabilizacion. A manera de conclusion, se puede afirmar que en ambos sistemas escolares las politicas de evaluacion externa vienen comprometiendo los principios de la educacion publica mediante la incorporacion de la racionalidad mercadologica por intermedio de la competicion y la gestion, enmascarando las contradicciones sociales y perpetuando las profundas diferencias individuales y colectivas derivadas de la pobreza y la opresion, resultantes del actual modelo de produccion y consumo. EnglishThis article critically analyzes the external evaluation policies implemented in Colombia and Brazil, in the context of capitalist society. Official and legal documents were analyzed, and the chosen perspective was the Comparative Historical Studies within the theoretical-methodological matrix of Historical-Dialectical Materialism. Research results showed that international organizations at the service of capital exert influence on the evaluation policies of both countries through the ideologies of merit and management. As a conclusion it is possible to affirm that in both school systems the policies of external evaluation are compromising the principles of public education by incorporating marketing rationality through competition and management, masking social contradictions and perpetuating the serious individual and group differences derived from poverty and oppression, which are a consequence of the current model of production and consumption. portuguesO objetivo deste artigo e analisar criticamente as politicas externas de avaliacao implementadas na Colombia e no Brasil, no contexto da sociedade capitalista. Com base nesse interesse, foram analisados documentos oficiais e legais, adotando-se a perspectiva dos Estudos Historicos Comparativos dentro da matriz teorico- metodologica do Materialismo Historico-Dialetico. Os resultados da pesquisa mostraram que as organizacoes internacionais que servem a capital, como o Banco Mundial, exercem influencia sobre avaliacao de politicas em ambos paises pelas ideologias de merito e gestiogracia, refletidas atraves da aplicacao de testes padronizados, a disposicao de indicadores de qualidade e organizacao de um sistema de responsabilidade. Para concluir, podemos dizer que em ambos sistemas escolares as politicas de avaliacao externa estao comprometendo os principios da educacao publica, incorporando a racionalidade mercadologica atraves da competicao e gestao, mascarando contradicoes sociais e perpetuando profundas diferencas individuais e coletivas derivadas da pobreza e da opressao, resultantes do atual modelo de producao e consumo.

This work aimed to analyze the historical determinations of contemporary school evaluation from on the Dialectical Historical Materialism. The research reveals that in general terms a formalist, technical-instrumental vision of the evaluation has prevailed, inherited from an exclusive and oppressive system, reproducing an abstract and elitist meritocracy, contrary to the full formation of the collective critical consciousness and social transformation.; Este trabajo, resultado de una tesis doctoral sobre políticas de evaluación externa en Colombia y Brasil, tuvo como objetivo analizar las determinaciones históricas de la evaluación escolar contemporánea a partir del Materialismo Histórico Dialéctico. La investigación revela que en términos generales ha prevalecido una visión formalista, técnico-instrumental de la evaluación, heredada de un sistema excluyente y opresor, reproductor de una meritocracia abstracta y elitista, contraria a la formación plena de la conciencia crítica colectiva y la transformación social.

Este trabajo presenta el uso de inteligencia artificial en flujos multifásicos, implementando una red neuronal artificial de perceptrón multicapa con retropropagación, y utilizando la función de activación tangente sigmoidea, para generar un modelo predictivo capaz de obtener la fracción volumétrica de un flujo bifásico compuesto por agua y aceite mineral en una tubería horizontal de 12 m. La red neuronal artificial se desarrolla a partir de una capa de entrada, formada por el diferencial de presión en la línea y las velocidades superficiales de los fluidos de trabajo, además, tiene dos capas ocultas y una capa de salida, que está formada por las fracciones volumétricas de los fluidos. El modelo predictivo de mejor rendimiento muestra un error medio porcentual absoluto del 3,07 % y un coeficiente de determinación R2 de 0,985 utilizando 15 neuronas en las dos capas ocultas de la red neuronal. Los 56 datos experimentales utilizados en el estudio se obtuvieron en el laboratorio LEMI EESC-USP (Brasil).

La cavitación hidrodinámica es una tecnología implementada recientemente para aplicaciones industriales, como el tratamiento de aguas, la generación de biocombustibles o el mejoramiento de los crudos pesados. Los crudos pesados se caracterizan por su baja gravedad API y su alta viscosidad, lo que resulta en un mayor costo de extracción, transporte y refinamiento, y un menor precio de venta por su menor contenido de fracciones livianas como la nafta. Por lo tanto, los reactores de cavitación hidrodinámica se utilizan para cavitar el crudo y mejorar la viscosidad, y la eficiencia depende en gran medida de los parámetros operativos, como la presión de entrada, la temperatura y el porcentaje de un donante de hidrógeno. En este trabajo se analiza el efecto de la temperatura sobre la dinámica de fluidos del crudo en el interior del reactor Vortex HCR-Nano, tomando como variable de respuesta la fracción volumétrica de vapor. El estudio CFD se realizó utilizando Ansys Fluent, con cinco temperaturas diferentes entre 92 ◦ F y 350 ◦ F, modelado 3D de flujo en estado estacionario para fluido multifásico líquido-vapor, con modelo de turbulencia realisable k-ε y cavitación Schnerr-Sauer. Los resultados muestran que el volumen de vapor aumenta con la temperatura hasta, hasta un volumen de 1.507 cm3, donde la principal contribución se debe al efecto Vortex. Investigación adicional incluye el comportamiento de la cavitación hidrodinámica con diferentes crudos y parámetros operativos.

Recently, several real quantum devices have become available through the cloud. Nevertheless, they are expected to be very limited, in the near term, in the number and quality of the fundamental storage element, the qubit. Therefore, software quantum simulators are the only widely available tools to design and test quantum algorithms. However, the representation of quantum computing components in classical computers consumes a big amount of resources. This work describes how to model the main elements of quantum computing in a classical computer and depicts resource consumption using two popular quantum simulators. In the end, we discuss different approaches to overcome this problem. Resumen Recientemente, varios dispositivos cuánticos reales están disponibles a través de la nube. No obstante, se espera que sean muy limitados, a corto plazo, en el número y la calidad del elemento fundamental de almacenamiento, el qubit. Por lo tanto, los simuladores cuánticos de software son las únicas herramientas ampliamente disponibles para diseñar y probar algoritmos cuánticos. Sin embargo, la representación de componentes de computación cuántica en computadoras clásicas consume una gran cantidad de recursos. Este trabajo describe cómo modelar los elementos principales de la computación cuántica en una computadora clásica y describe el consumo de recursos utilizando dos simuladores cuánticos populares. Al final, discutimos diferentes enfoques para superar este problema.

A recovery-based error indicator developed to evaluate the quality of polygonal finite element approximations is presented in this paper. Generalisations of the finite element method to arbitrary polygonal meshes have been increasingly investigated in the last years, as they provide flexibility in meshing and improve solution accuracy. As any numerical approximation, they have an induced error which has to be accounted for in order to validate the approximate solution. Here, we propose a recovery type error measure based on a moving least squares fitting of the finite element stress field. The quality of the recovered field is improved by imposing equilibrium conditions and, for singular problems, splitting the stress field into smooth and singular parts. We assess the performance of the error indicator using three problems with exact solution, and we also compared the results with those obtained with standard finite element meshes based on simplexes. The results indicate good values for the local and global effectivities, similar to the values obtained for standard approximations, and are always within the recommended range.

International audience; Since 2012, in a case-study in Bucaramanga-Colombia, 179 pedestrians died in car accidents, and another 2873 pedestrians were injured. Each day, at least one passerby is involved in a tragedy. Knowing the causes to decrease accidents is crucial, and using system-dynamics to reproduce the collisions' events is critical to prevent further accidents. This work implements simulations to save lives by reducing the city's accidental rate and suggesting new safety policies to implement. Simulation's inputs are video recordings in some areas of the city. Deep Learning analysis of the images results in the segmentation of the different objects in the scene, and an interaction model identifies the primary reasons which prevail in the pedestrians or vehicles' behaviours. The first and most efficient safety policy to implement-validated by our simulations-would be to build speed bumps in specific places before the crossings reducing the accident rate by 80%.

Background Chagas disease is an infectious disease caused by the parasite Trypanosoma cruzi and is endemic from Latin American countries. The goal of our study was to identify novel genetic loci associated with chronic Chagas cardiomyopathy development in Chagas disease patients from different Latin American populations. Methods We performed a cross-sectional, nested case-control study including 3 sample collections from Colombia, Argentina, and Bolivia. Samples were genotyped to conduct a genome-wide association study (GWAS). These results were meta-analyzed with summary statistic data from Brazil, gathering a total of 3413 Chagas disease patients. To identify the functional impact of the associated variant and its proxies, we performed an in silico analysis of this region. Results The meta-analysis revealed a novel genome-wide statistically significant association with chronic Chagas cardiomyopathy development in rs2458298 (OR = 0.90, 95%CI = 0.87–0.94, P-value = 3.27 × 10-08), nearby the SAC3D1 gene. In addition, further in silico analyses displayed functional relationships between the associated variant and the SNX15, BAFT2, and FERMT3 genes, related to cardiovascular traits. Conclusions Our findings support the role of the host genetic factors in the susceptibility to the development of the chronic cardiac form of this neglected disease.

International audience; This work aimed to analyze the historical determinations of contemporary school evaluation from on the Dialectical Historical Materialism. The research reveals that in general terms a formalist, technical-instrumental vision of the evaluation has prevailed, inherited from an exclusive and oppressive system, reproducing an abstract and elitist meritocracy, contrary to the full formation of the collective critical consciousness and social transformation.; Este trabajo, resultado de una tesis doctoral sobre políticas de evaluación externa en Colombia y Brasil, tuvo como objetivo analizar las determinaciones históricas de la evaluación escolar contemporánea a partir del Materialismo Histórico Dialéctico. La investigación revela que en términos generales ha prevalecido una visión formalista, técnico-instrumental de la evaluación, heredada de un sistema excluyente y opresor, reproductor de una meritocracia abstracta y elitista, contraria a la formación plena de la conciencia crítica colectiva y la transformación social.; O presente trabalho teve como objetivo analisar criticamente as determinações materiais da relação avaliação-aprendizagem durante o desenvolvimento histórico da educação antiga, moderna e contemporânea, com base na matriz teórico-metodológica do Materialismo Histórico-Dialético. A tese defendida sustenta que a avaliação escolar é uma consequência histórica da rotura da unidade dialética entre prática e teoria. Em função dessa dicotomia e das respectivas bases materiais e ideológicas do atual modelo de produção e consumo, a avaliação educacional continua a ser utilizada como mediação hegemônica entre poder, classismo e conhecimento-habilidade.

In this work, we analyse the results of the reported mechanical properties for a particular kind of continuous fibre-reinforced thermoplastic composites (CFRTPC) manufactured by fused deposition modelling (FDM). A summary of reported mechanical properties available in Scopus and Web of Science databases as well as cross-references was gathered. Listed materials include a Nylon matrix reinforced with continuous fibres of carbon (CRTP), Kevlar (KvRTP), and fibreglass (FGRTP) used for the Markforged printer. The reported experiments are tension, bending, and shear, where fibres were oriented at 45° from the load axis. The reported properties include elasticity modulus, Poisson ratio, ultimate stress in a parallel-to-load direction, and, in some cases, the same properties in the perpendicular-to-load direction. For impact, there was found a comprehensive study reporting Izod testing. Moreover, fatigue is reported for FGRTP composites under uniaxial alternative testing, with one of them testing CRTP, and KvRTP as well as providing Wohler curves. Fractography is also discussed. There is also one study reporting creep testing. From the summary of reported properties, it was found a wide variation of mechanical properties, lack of reporting of an appropriate fibre volume fraction and how such content was estimated. The paper discusses reported mechanical properties under different types of loading for three types of CFRTPC composites, CRTP, FGRTP, and KvRTP. Finally, there are recommendations to perform missing studies reporting relevant aspects of damage mechanisms in composites such as wear, water absorption, UV effect on mechanical properties, toughness, and fatigue crack growth threshold.

A very low dimension frame-level motion descriptor is herein proposed with the capability to represent incomplete dynamics, thus allowing online action prediction. At each frame, a set of local trajectory kinematic cues are spatially pooled using a covariance matrix. The set of frame-level covariance matrices forms a Riemannian manifold that describes motion patterns. A set of statistic measures are computed over this manifold to characterize the sequence dynamics, either globally, or instantaneously from a motion history. Regarding the Riemannian metrics, two different versions are proposed: (1) by considering tangent projections with respect to updated recursive statistics, and (2) by mapping the covariance onto a linear matrix using as reference the identity matrix. The proposed approach was evaluated for two different tasks: (1) for action classification on complete video sequences and (2) for online action recognition, in which the activity is predicted at each frame. The method was evaluated using two public datasets: KTH and UT-interaction. For action classification, the method achieved an average accuracy of 92.27 and 81.67%, for KTH and UT-interaction, respectively. In partial recognition task, the proposed method achieved similar classification rate as for the whole sequence using only the 40 and 70% on KTH and UT sequences, respectively. The code of this work is available at [code].

Deep Learning models have come into significant use in the field of biology and healthcare, genomics, medical imaging, EEGs, and electronic medical records [1, 2, 3, 4]. In the training these models can be affected due to overfitting, which is mainly due to the fact that Deep Learning models try to adapt as much as possible to the training data, looking for the decrease of the training error which leads to the increase of the validation error. To avoid this, different techniques have been developed to reduce overfitting, among which are the Lasso and Ridge regularization, weight decay, batch normalization, early stopping, data augmentation and dropout. In this research, the impact of the neural network architecture, the batch size and the value of the dropout on the decrease of overfitting, as well as on the time of execution of the tests, is analyzed. As identified in the tests, the neural network architectures with the highest number of hidden layers are the ones that try to adapt to the training data set, which makes them more prone to overfitting.

Galaxies in dense environments are subject to interactions and mechanisms which directly affect their evolution by lowering their gas fractions and reducing their star-forming capacity earlier than their isolated counterparts. The aim of our project is to get new insights about the role of environment on the stellar and baryonic content of galaxies using a kinematic approach, through the study of the Tully-Fisher relation (TFR). We study a sample of galaxies in 8 groups spanning a redshift range of $0.5, Comment: Accepted for publication in Astronomy & Astrophysics

International audience; In the preliminary stage of the industrial design, the structural analysis of the components made of composite materials is generally difficult to carry out for aircraft structures having complex three-dimensional geometry. More importantly, in the case of composite structures, the lay-up process creates a particular distribution of the material properties that is challenging to simulate in a virtual environment. This research work is, therefore, focused on the use of the finite element method for the numerical analysis and the structural redesign of the bulkhead and flap aircraft components. In particular, the numerical results obtained in this work are the stress and strain fields of these mechanical components. The redesign and the structural optimization of these two mechanical components are performed employing a simple numerical procedure. For this purpose, the quality of the stress and strain fields obtained by performing numerical experiments is evaluated considering failure criteria suitable for composite structures. Subsequently, the analysis developed in this study is used for determining the performance of the material as well as the number and orientation of the plies selected for the composite components. The verification process performed in this work, on the other hand, consisted of a comparative analysis with the same aerospace components made of isotropic and anisotropic materials. The numerical results found are compared with the experimental results available for the aerospace components that are geometrically and functionally similar to the bulkhead. In general, a good agreement is found in the comparison between the numerical and experimental results.

Natural or human-made disasters could do huge damage in urban areas and eventually could take lives. It is fundamental to get knowledge of the event’s characteristics to dispose of hasty information to help affected people or to prevent all the citizens from the danger zone, and then it will get time to respond to the crisis. Internet of Things (IoT) has a big impact on this kind of situation because a large amount of data through different devices could provide information about the situation, and about the people that are involved in the crisis. In a disaster, one of the big problems adding to the principal crisis is the disinformation, for that reason is necessary to have available and trusty data in case of disaster, also to know the data that provided the information system. To inform the affected people around the crisis event, there is exist some previous works that have used data from sensors, social networks text, or images, to finally be processed [1],[2],[3],[4],[5],[6],[7],[8]. This paper aims to review study-cases where cities implement crisis management platforms, focus on IoT environment where applications use hybrid data to be processed to help citizens in a crisis situation. Natural or human-made disasters could do huge damage in urban areas and eventually could take lives. It is fundamental to get knowledge of the event’s characteristics to dispose of hasty information to help affected people or to prevent all the citizens from the danger zone, and then it will get time to respond to the crisis. Internet of Things (IoT) has a big impact on this kind of situation because a large amount of data through different devices could provide information about the situation, and about the people that are involved in the crisis. In a disaster, one of the big problems adding to the principal crisis is the disinformation, for that reason is necessary to have available and trusty data in case of disaster, also to know the data that provided the information system. To inform the affected people around the crisis event, there is exist some previous works that have used data from sensors, social networks text, or images, to finally be processed [1],[2],[3],[4],[5],[6],[7],[8]. This paper aims to review study-cases where cities implement crisis management platforms, focus on IoT environment where applications use hybrid data to be processed to help citizens in a crisis situation., Los desastres naturales o provocados por el hombre podrían causargrandes daños en las áreas urbanas y eventualmente podrían cobrarvidas. Es fundamental conocer las características del evento para disponerde rápida respuesta para ayudar a las personas afectadas o para evitarque todos los ciudadanos salgan de la zona de peligro, y luego setendrá tiempo de responder a la crisis. El internet de las cosas (IoT)tiene un gran impacto en este tipo de situaciones porque con una grancantidad de datos a través de diferentes dispositivos podrían brindarinformación suficiente sobre la situación y sobre las personas involucradasen medio de la crisis. En un desastre, uno de los grandes problemas esla desinformación, por eso es necesario tener datos confiables en casode desastre, y disponer de una infraestructura capáz de responder enun estado de emergencia. Para informar a las personas afectadas sobreel evento de crisis, existen algunos trabajos previos que han utilizadodatos de sensores, texto de redes sociales o imágenes, para finalmente serprocesados [1],[2],[3],[4],[5],[6],[7],[8]. Este documento tiene como objetivorevisar los casos de estudio donde las ciudades implementan plataformasde gestión de crisis, y se centra en el entorno de IoT donde las aplicacionesutilizan datos híbridos para ser procesados y ayudar a los ciudadanos enuna situación de crisis.

International audience; This research deals with the catalytic behavior of the methane steam reforming reaction over a new Ni-exsolved Ruddlesden-Popper manganite during prolonged reaction time (up to 100 h) with special focus on the possible carbon deposition and H2S poisoning. La1.5Sr1.5Mn1.5Ni0.5O7±δ material was synthesized and reduced in diluted hydrogen to induce Ni exsolution. Its catalytic behavior in long reaction times was compared to Ni-impregnated manganite and Ni/YSZ cermet. The catalytic measurements for the steam reforming reaction were carried out at 850 °C in low steam-to-carbon conditions. All materials are susceptible to H2S poisoning (50 ppm), forming undesired sulfide compounds with damaging impact on their catalytic activity. In contrast, during tests without H2S, the activity for cermet and impregnated materials drops at relatively short reaction time due to coking formation, as evidenced by TEM and TGA/MS analysis, while the behavior of new exsolved material remains stable throughout the test. This high stability of the new exsolved catalyst over a prolonged reaction time is a noticeable advantage due to its potential use as SOFC anode fed with natural gas free of H2S.

International audience

International audience; The integration of Demand-Side Management (DSM) in the planning of Isolated/Islanded Microgrids (IMGs) can potentially reduce total costs and customer payments or increase renewable energy utilization. Despite these benefits, there is a paucity in literature exploring how DSM affects the planning and operation of IMGs. The present work compares the effects of five different strategies of DSM in the planning of IMGs to fulfill the gaps found in the literature. The present work embodies a Disciplined Convex Stochastic Programming formulation that integrates the planning and operation of IMGs using three optimization levels. The first level finds the capacities of the energy sources of the IMG. The second and third levels use a rolling horizon for setting the day-ahead prices or the stimulus of the DSM and the day-ahead optimal dispatch strategy of the IMG, respectively. A case study shows that the Day-Ahead Dynamic Pricing DSM and the Incentive-Based Pricing DSM reduce the total costs and the Levelized Cost of Energy of the project more than the other DSMs. In contrast, the Time of Use DSM reduces the payments of the customers and increases the delivered energy more than the other DSMs

espanolLa manufactura aditiva es un metodo de fabricacion reciente en el que la pieza se produce capa por capa a partir de un modelo CAD 3D. En este trabajo, presentamos la caracterizacion mecanica del Fusion Deposition Modeling (FDM) aplicada a partes compuestas hechas por una matriz de nailon con dos tipos de refuerzos de fibra: fibra de carbono o fibra de vidrio. A partir de la microestructura obtenida, se realiza una division de la parte compuesta en regiones, y se encuentran matrices de rigidez individuales utilizando un modelo isotropico elastico lineal, para el caso de relleno de matriz solida, o un modelo elastico ortotropico lineal basado en resultados micromecanicos. Luego, se emplea un metodo de rigidez promedio de volumen para realizar la caracterizacion de la parte completa. Los resultados teoricos se comparan con los datos experimentales, mostrando una buena concordancia en ambos casos. Esta investigacion permite la prediccion del comportamiento estructural de las piezas compuestas de fabricacion aditiva. EnglishAdditive Manufacturing is a novel manufacturing method in which the part is produced layer by layer from a 3D CAD model. In this work, we present the mechanical characterization of Fusion Deposition Modeling (FDM). Composite parts made by a nylon matrix with two kinds of fiber reinforcements: carbon fiber or fiberglass. From the obtained microstructure, we perform a division of the composite part in regions, and individual stiffness matrices are encountered by either using a linear elastic isotropic model, for the case of solid matrix filling, or an orthotropic linear elastic model based on micromechanical results. Then, a volume average stiffness method is employed to perform the characterization of the whole part. The theoretical results are compared with the experimental data, showing good agreement for both cases. This research allows the prediction of the structural behavior of additive manufacturing 2composite parts.

Bone metastasis to the spine, pelvis, or hip in patients suffering from prostate cancer occurs in about 80% of cases. A spinal metastasis may cause pain, instability and neurological injuries. Thus, it is relevant to assess when critical conditions have been reached and bone structural integrity is compromised. Data-driven numerical methods based on the postprocessing of medical imaging provide a tool to model the material complexity of biological tissues. Computed axial tomography (CAT) together with segmentation tools allow the reconstruction of 3D models of the bone that include mechanical properties representing the anisotropic condition of the bone structures. In this work, we present the model of the L5 lumbar vertebra of a patient affected by metastasis, and evaluate biomarkers to indicate the level of damage, compared with the reference case of a healthy bone in an initial stage., La metástasis ósea a la columna vertebral, la pelvis o la cadera en pacientes con cáncer de próstata es una patología que ocurre en aproximadamente el 80% de los casos. La metástasis en la columna vertebral puede causar dolor, inestabilidad y lesiones neurológicas. Por lo tanto, es relevante evaluar cuándo se han alcanzado condiciones críticas y la integridad estructural del hueso está comprometida. Los métodos numéricos basados en datos del paciente, obtenidos mediante el postprocesamiento de imágenes médicas, proporcionan una herramienta para modelar la complejidad del material de los tejidos biológicos. La tomografía axial computarizada (TAC) junto con las herramientas de segmentación permiten la reconstrucción de modelos 3D del hueso que incluyen propiedades mecánicas, y que representan la condición anisotrópica de las estructuras óseas. En este trabajo, presentamos el modelo de la vértebra lumbar L5 de un paciente afectado por metástasis y evaluamos biomarcadores para indicar el nivel de daño, comparando con el caso de referencia del hueso sano en una etapa inicial. Palabras clave: daño óseo; segmentación ósea; vértebras; metástasis; FEA basado en imagen.

A thorough study of the Y1−xZrxMnO3+δ series is presented with the objective to use these materials as SOFC cathodes. These pure and Zr-doped yttrium manganites exhibit a layered hexagonal structure similar to a peculiar 5-fold bipyramidal coordination of manganese that makes them intrinsically different from the traditional cube-like perovskite with [MnO6] octahedra, creating the conditions conducive for oxygen uptake at a low temperature in the case of the layered manganite. Zr for Y doping enables the maintenance of oxygen excess such as interstitial oxygen atoms (Oi) located in the equatorial plane of the bi-pyramids. These over-stoichiometric interstitial oxygen sites are clearly evidenced by the maximum entropy method (MEM) applied to neutron diffraction data, and density functional theory (DFT) calculations are used to model the structural accommodation of Zr and excess oxygen. Mn reduction to Mn2+ is found to be energetically unfavourable, as proved both experimentally and by DFT calculations. Hence, zirconium is found to both stabilize the excess oxygen compared to pure YMnO3 and possibly provide an oxygen ion migration path with a lower energy barrier. The main consequence is a possible MIEC behaviour in Zr-doped YMnO3, as suggested by both the conductivity measurements and theoretical calculations. The initial EIS measurements are very promising and raise the series and its original structure to the rank of materials of interest for application as SOFC electrodes. © 2019. This is the authors' accepted and refereed manuscript to the article. The final authenticated version is available online at: http://dx.doi.org/10.1039/C9TA04912F

International audience; Two polytypes of the new oxyvanadate matrix La7O6(VO4)3 were identified and deeply characterized. The crystal structure of the α-polytype was solved using a combination of precession electron diffraction and powder X-ray diffraction (XRD) techniques. It crystallizes in a monoclinic unit cell with space group P21, a = 13.0148(3) Å, b = 19.1566(5) Å, c = 7.0764(17) Å, and β = 99.87(1)°. Its structure is built upon [La7O6]9+ polycationic units at the origin of a porous 3D network, evidencing rectangular channels filled by isolated VO4 tetrahedra. An in situ high-temperature XRD study highlights a number of complex phase transitions assorted with the existence of a β-polytype also refined in a monoclinic unit cell, space group P21/n, a = 13.0713(4) Å, b = 18.1835(6) Å, c = 7.1382(2) Å, and β = 97.31(1)°. Thus, during the transitions, while the polycationic networks are almost identical, the vanadate’s geometry is largely modified. The use of Eu3+ and Sm3+ at different concentrations in the host lattice is possible using solid-state techniques. The photoluminescence (PL), PL excitation (PLE) spectra, and luminescence decay times were recorded and discussed. The phosphors present an emission light, being bright and reddish orange after excitation under UV. This is mainly due to the V–O band and f–f transitions. Whatever the studied polytype, the final luminescence properties are retained during the heating/cooling process.

In additive manufacturing (AM), thermoplastic components made by fused deposition modeling (FDM) offer low strength and stiffness, as required for fully functional and load-bearing parts. Composite materials are a practical solution to improve mechanical properties [1,2]. A new technology to reinforce thermoplastics with continuous fibers has been developed recently by Markforged [3]. It introduces continuous fiber to reinforce a thermoplastic matrix, thus, taking static mechanical performance close to Aluminum alloys [1,4]. These printers for continuous fiber reinforced thermoplastic composites (CFRTPC) have taken this technology to a whole new level in terms of mechanical properties and efficient production. Mechanical properties under monotonic load were studied for different kinds of printing configurations. Tensile monotonic tests under controlled displacement were performed until rupture. Raw data showing tensile monotonic behavior provides the researchers with the ability to perform data fitting, to validate more advanced constitutive models, or to perform a further interpretation of the data, among others. Data is presented here as plain text files without any analysis. A preliminary data analysis has been published already in [5]. The text files contain information about time, displacement, and force. The data is useful for design engineers and researchers involved with AM. Keywords: Additive manufacturing (AM), Fused deposition modeling (FDM), Continuous fiber reinforced thermoplastic composites (CFRTPC), Stress in thermoplastics, Mechanical properties

International audience; In this work, we present a model for the initiation and evolution of damage for a composite fibre-reinforced pipe used in the Oil & Gas industry, based on a commercially available pipe. A continuum damage mechanics model was employed to determine the initiation and evolution of damage. This model was implemented using finite element analysis to investigate the performance of the commercial composite pipe. Initially, the material properties were obtained from experimental data and fitting with static structural simulations. Then, FE simulations with damage were performed, considering three different boundary conditions: open, closed (pressure-vessel type) and fixed ends, the load considered was internal pressure. Results showed differences not only in the stress distribution but on the damage initiation and evolution along the geometry of the pipe. These differences in the damage initiation and propagation can be explained as the result of different axial-hoop stress ratio.

International audience; Three-dimensional (3D) printing technology has been traditionally used for the production of prototypes. Recently, developments in 3D printing using Fused Deposition Modelling (FDM) and reinforcement with continuous fibres (fiberglass and carbon fibre), have allowed the manufacture of functional prototypes, considerably improving the mechanical performance of the composite parts. In this work, we characterise the elastic tensile properties of fibre reinforced specimens, considering the variation of several parameters available during the printing process: fibre orientation, volume fraction, fill pattern, reinforcement distribution. Tensile tests were performed according to ASTM D638 to obtain Young's modulus and ultimate strength for different material configurations available during the printing process. We also perform a fractographic analysis using Scanning Electron Microscopy (SEM) to give an insight of the failure mechanisms present in the specimens.

NdxAE2-xMnO4±δ (AE: Ca, Sr) manganites with x = 0.25, 0.4, 0.5 and 0.60 are part of the Ruddlesden-Popper family of generic formula An+1BnO3n+1 with n = 1. The compositions range that can be successfully synthesized by the sol-gel method in air has been identified. While Sr compounds are stable in reducing atmosphere (3% H2/Ar - 850 °C/16 h), Ca ones decompose when submitted to such atmosphere. Nd0.5Sr1.5MnO4±δ was analyzed by High-Temperature X-ray diffraction (HT-XRD) showing TEC values of 12.7 × 10−6 K−1 and 14.4 × 10−6 K−1 in air and 3% H2/N2 (25–800 °C), respectively. Using standard conditions for electrode elaboration, the material reacts with YSZ electrolyte, but is chemically compatible with GDC electrolyte. A small polaron-type behavior is observed for the electrical conductivity of Nd0.5Sr1.5MnO4±δ in air and 3% H2/Ar, with respective values of 33.4 S cm−1 and 0.9 S cm−1 at 800 °C, meeting the preliminary requirements for use as symmetrical SOFC electrode.

The present review is a sequel to the previous review on cancer metabolism published in this journal. This review focuses on the selective antiproliferative and cytotoxic effects of mitochondria-targeted therapeutics (MTTs) in cancer cells. Emerging research reveals a key role of mitochondrial respiration on tumor proliferation. Previously, a mitochondria-targeted nitroxide was shown to selectively inhibit colon cancer cell proliferation at submicromolar levels. This review is centered on the therapeutic use of MTTs and their bioenergetic profiling in cancer cells. Triphenylphosphonium cation conjugated to a parent molecule (e.g., vitamin-E or chromanol, ubiquinone, and metformin) via a linker alkyl chain is considered an MTT. MTTs selectively and potently inhibit proliferation of cancer cells and, in some cases, induce cytotoxicity. MTTs inhibit mitochondrial complex I activity and induce mitochondrial stress in cancer cells through generation of reactive oxygen species. MTTs in combination with glycolytic inhibitors synergistically inhibit tumor cell proliferation. This review discusses how signaling molecules traditionally linked to tumor cell proliferation affect tumor metabolism and bioenergetics (glycolysis, TCA cycle, and glutaminolysis). Keywords: Triphenylphosphonium cation, Pancreatic ductal adenocarcinoma, Extracellular acidification rate, Oxygen consumption rate, Coenzyme Q10

International audience; This paper proposes a new motion estimation method based on convolutional sparse coding to adaptively design the colored-coded apertures in static and dynamic spectral videos. The motion in a spectral video is estimated from a low-resolution reconstruction of the datacube by training a convolutional dictionary per spectral band and solving a minimization problem. Simulations show improvements in terms of peak signal-to-noise ratio (of up to 2 dB) of the reconstructed videos by using the proposed approach, compared with state-of-art non-adaptive coded apertures.

International audience; The objective of this research is to critically analyze the concrete determinations of higher education policies that define the contractual relationship of the adjunct professors in Colombia. The theoretical-methodological approach of materialism dialectical-historical was adopted. Some Legal documents were studied. Also, some official documents and institutional agreements of a public university. Results requested that this type of contracting obeys recommendations from the World Bank; fosters the contradiction between training and work; it allows the university to grab the academic and educational production of teachers, as well. In conclusion, this professionalbecomes a working subject without rights, a new “slave”of the 21st century with which universities reach goals of academic quality, fiscal and financial efficiency, though.; Se pretendieron analizar las determinaciones concretas de las políticas de educación superior que definen la vinculación contractual del docente cátedra en Colombia. Se adoptó el enfoque teórico-metodológico del materialismo histórico-dialéctico para estudiar documentos jurídicos, oficiales y acuerdos institucionales de una universidad pública. Resultados demuestran que este tipo de contratación obedece recomendaciones del Banco Mundial; fomenta la contradicción entre formación y trabajo; permite que la universidad se apropie de la producción académica y educativa del profesorado. En conclusión, este profesional se convierte en sujeto trabajador sin derechos, un nuevo “esclavo” del siglo XXI con el cual las universidades alcanzan metas de calidad académica, eficiencia fiscal y financiera.; L'objectif était d'analyser les déterminations des politiques d'enseignement supérieur qui définissent la relation d'emploi du personnel enseignant en Colombie. L'approche théorico-méthodologique du matérialisme historico-dialectique a été adoptée pour étudier des documents juridiques, officiels et des accords institutionnels d'une université publique. Les résultats montrent que ce type de contrat obéit aux recommandations de la Banque Mondiale; favorise la contradiction entre la formation et le travail; Il permet à l'université de s'approprier de la production académique et pédagogique des enseignants. En conclusion, ce professionnel devient un sujet de travail sans droits, un nouvel “ esclave ” du 21e siècle avec lequel les universités atteignent des objectifs de qualité académique, d'efficacité fiscale et financière.; O objetivo foi analisar as determinaçõesconcretasdas políticas de ensino superior que definem a relação contratual do professor catedrático na Colômbia. A abordagem teórico-metodológica do materialismo histórico-dialético foi adotada para estudar documentos legais, oficiais e acordos institucionais de uma universidade pública. Resultados mostram que esse tipo de contratação obedece recomendações do Banco Mundial; promove a contradição entre formaçãoe trabalho; permite que a universidade se aproprie da produção acadêmica e educacional dos professores. Concluindo, esse profissional se torna um sujeito de trabalho sem direitos, um novo “ escravo ” do século XXI com o qual as universidades atingem metas de qualidade acadêmica, eficiência fiscal e financeira.

International audience; Con el comienzo de una nueva década, se vislumbran fuertes cambios en muchos de los paradigmas de la ingeniería, y por supuesto, dichos cambios afectarán nuestra sociedad [1]. La aparición de tecnologías disruptivas como, por ejemplo, la inteligencia artificial, la manufactura aditiva, la realidad aumentada, plantean un nuevo escenario para la ingeniería, donde se fortalecerán los países que adopten oportunamente estas nuevas tecnologías. En este sentido, es importante hacer una valoración del estado actual de la investigación en el área de ingeniería en Colombia, y tratar de definir un escenario donde podamos hacer frente, de manera efectiva, a los nuevos retos que se plantean en esta nueva revolución industrial. En la Figura 1 se muestran cifras referentes a la evolución de la investigación en el área de Ingeniería para Latinoamérica, según los registros de Scopus. En la Figura 1(a) se representa la producción científica para cada país vs. el número de publicaciones indexadas en Scopus [2] para el año 2018. Se observa la relación proporcional entre la producción y el número de revistas, siendo Brasil el primer país de la región con 18 revistas indexadas y 10363 documentos registrados. Colombia se ubica en el tercer lugar, con una proporción ligeramente más alta de revistas, con 6 revistas indexadas, y una producción de 2243 documentos. La Figura 1(b) muestra la evolución de la producción científica para los cuatro primeros países de la región entre los años 1996 y 2018. Brasil ha sido el país dominante en el área de Ingeniería, con una producción total de 115610 documentos y un índice de impacto h = 205. Colombia ocupaba el cuarto lugar en la región hasta el 2009, año en que superó a Chile. Hoy en día Colombia continua en el tercer lugar, con una producción total de 16678 documentos y un índice h = 94 para el mismo período. Estos resultados muestran un avance positivo en la investigación en el área de Ingeniería para el país, especialmente si tenemos en cuenta que, según datos del Banco Mundial [3], Brasil invierte 1.27% de su PIB en investigación y desarrollo, mientras que Colombia quedaría de cuarto en este mismo grupo, con una inversión del 0.24% del PIB.

International audience; In this study, a novel technique for multiple damage detection of structures using modal characterization to evaluate the dynamic response of the structure given a damage model is investigated. The damage identification problem is seen as an optimization problem to be solved using a firefly optimization algorithm. The objective function is based on a numerical damage model that considers the modal response of the structures. We show some implementation details and discuss the obtained results for a benchmark problem used to assess the performance of the method and its advantages for structural health monitoring.; El presente trabajo tiene por objeto investigar la detección de daños en estructuras como un problema de optimización, utilizando la caracterización modal para evaluar la respuesta dinámica de la estructura ante un modelo de daño. Se llevó a cabo la implementación del algoritmo de optimización de la luciérnaga, tomando como caso de estudio un modelo numérico de daño sencillo, para ver los alcances del método propuesto y sus ventajas dentro del campo de monitoreo estructural (SHM). Se indican detalles de la implementación y los resultados obtenidos con este planteamiento.

International audience; This work presents the finite element analysis of partially stiffened cylinders subjected to axial compression at elevated temperatures. The compressive strength is calculated for self-weight conditions and the influence of the temperature on the material response is also investigated. In the oil industry, pressure vessels are commonly used operating at complex design conditions such as high-pressure profiles and/or elevated temperature gradients which affect considerably the structural response of inner components. Among them, risers become sensitive steel elements withstanding heavy compressive loading due to self-weight, as well as, insulation elements added to protect them from the elevated temperature gradient. Most risers structurally fail at the bottom end due to buckling caused by self-weight and temperature effects. To remediate this situation and to guarantee the integrity of the riser, longitudinal stiffeners are welded at the bottom end. Hence, a proper determination of the compressive strength of the cylinder, taking into account the influence of the longitudinal stiffening and the corresponding temperature, is required. Results indicate that the use of longitudinal stiffeners in deformed cylinders increases the strength to buckling in percentages that vary according to the cross-section of the profiles.; Este trabajo presenta el análisis de elementos finitos de cilindros parcialmente rígidos sometidos a compresión axial a temperaturas elevadas. La resistencia a la compresión se calcula para las condiciones de peso propio y también se investiga la influencia de la temperatura en la respuesta del material. En la industria del petróleo, los recipientes a presión se utilizan comúnmente para operar en condiciones de diseño complejas, como perfiles de alta presión y/o gradientes de temperatura elevados que afectan considerablemente la respuesta estructural de los componentes internos. Entre ellos, los raisers se convierten en elementos de acero sensibles que soportan una carga alta de compresión debido al peso propio, así como, elementos de aislamiento agregados para protegerlos del gradiente de temperatura elevada. La mayoría de los raisers fallan estructuralmente en el extremo inferior debido a la deformación causada por el peso propio y los efectos de temperatura. Para remediar esta situación y garantizar la integridad de la tubería vertical, los refuerzos longitudinales están soldados en el extremo inferior. Por lo tanto, se requiere una evaluación adecuada de la resistencia a la compresión del cilindro, teniendo en cuenta la influencia del refuerzo 132 E. longitudinal y la temperatura correspondiente. Los resultados indican que el uso de refuerzos longitudinales en cilindros deformados aumenta la resistencia al pandeo en porcentajes que varían de acuerdo con la sección transversal de los perfiles.

International audience; Additive manufacturing (AM) technologies have been applied with success in many applications, being fused deposition modelling (FDM) the most widely used AM technique for fabricating thermoplastic pieces. The thermoplastic parts made by FDM present lack of strength and low stiffness, as required for fully functional and load-bearing parts. Due to this restriction, a new technology to reinforce with fibres the thermoplastic filaments was developed in the last years. Continuous fibre reinforced thermoplastic composites (CFRTPC) printers are taking this technology to a whole new level in terms of efficient production and mechanical properties. Static mechanical properties, as well as fatigue behaviour, were studied since in these types of loads a wide range of engineering dynamic applications can be envisaged. Tensile tests were performed to characterise the static mechanical properties. Fatigue tests were done to analyse the durability behaviour of the FDM composite materials, and the fracture surface was analysed by SEM microscopy. The results showed that carbon fibre isotropic layers had the higher ultimate tensile stress, with 165 MPa. From fatigue tests, stress vs. number of cycles curves (S vs Nf) in the temporary life zone were obtained. It is observed from the results that specimens with nylon matrix, triangular filling pattern and matrix density of 20%, reinforced with carbon fibre at 0-degrees, showed better

International audience; This paper presents a descriptive study and scientometrics analysis to evaluate the incidence of the classification model of scientific journals Publindex in the behavior of Colombian journals in the area of Engineering and Technology. Qualitative and quantitative criteria were compiled, the production and contents of the journals were studied, and the national journals of the Engineering and Technology area were compared with the international journals of the same area. As a result, it is concluded that the implementation of the new categorization model served as a stimulus to boost the impact and improve the management of Colombian scientific journals in the study area. However, there is evidence of the need to implement models of editorial management and editorial policies (publication languages, periodicity, type of peer review, number of articles published, etc.) of international journals, and to rethink the classification model of scientific journals in Colombia incorporating guidelines that allow an objective evaluation based on the standardization and control of citation patterns.; En este artículo se presenta un estudio descriptivo y análisis cienciométrico para evaluar la incidencia del modelo de clasificación de revistas científicas de Publindex en el comportamiento del conjunto de revistas colombianas del área de Ingeniería y Tecnología. Se recopilaron criterios cualitativos y cuantitativos, se estudió la producción y contenidos de las revistas y se compararon las revistas nacionales del área de ingeniería y tecnología con las revistas internacionales de la misma área. Como resultado, se concluye que la implementación del nuevo modelo de categorización sirvió como estímulo para dinamizar la gestión e impacto, medido a través de indicadores de citación, de las revistas científicas colombianas del área de estudio. Sin embargo, se evidencia la necesidad de poner en práctica modelos de gestión editorial y políticas editoriales (idiomas de publicación, periodicidad, tipo de revisión, cantidad de artículos publicados, etc.) de revistas internacionales de referencia, y de replantear el modelo de clasificación de revistas científicas en Colombia incorporando directrices que permitan una evaluación objetiva a partir de la estandarización y control de patrones de citación.

Gamification refers to the use of game elements in contexts other than games. Each element that integrates it or the combination of these generates different psychological and motivational effects on users. Additionally, in recent years there has been an increasing trend in its use in educational settings, obtaining in most cases multiple benefits. Therefore, this study aims to analyze gamification based on the dynamics, mechanics, or components that comprise it, to provide suggestions for designing gamified systems. For this, an analysis of the literature about gamification, its elements and the effects generated on users is carried out. The results of this work indicate that elements such as points, narrative and feedback increase motivation and enjoyment, so it is recommended to incorporate them into educational gamified tools. Rather, caution must be exercised in designing challenges and using leaderboards and competition mechanics.; La gamificación hace referencia al uso de elementos del juego en contextos que no son juegos. Su impacto se debe a que la combinación de los elementos que la integran genera diferentes efectos psicológicos y motivacionales en los usuarios. Adicionalmente, en los últimos años se evidencia una tendencia creciente del uso de esta en entornos educativos, obteniendo múltiples beneficios en la mayoría de los casos. Por lo tanto, este estudio tiene como propósito analizar la gamificación en función de las dinámicas, mecánicas o componentes que la integran, con el fin de otorgar sugerencias para diseñar sistemas gamificados. Para esto se efectúa un análisis de la literatura acerca de la gamificación, sus elementos y los efectos que estos generan en los usuarios. Los resultados de este trabajo indican que elementos como puntos, narrativa y retroalimentación aumentan la motivación y el disfrute, por lo que se recomienda incorporarlos en herramientas gamificadas educativas. Por el contrario, se debe tener precaución con el diseño de los desafíos y el uso de tablas de clasificación y mecánicas de competición.

ispartof: Chemcatchem vol:12 issue:4 pages:1095-1108 status: published

Additive manufacturing makes possible to overcome the limitations of subtractive manufacturing and supposes a transformation with respect to the traditional processes, allowing to manufacture complex geometries by controlled deposition of material. In the automotive industry, the application of continuous fiber reinforcement, in combination with shape optimization for additive manufacturing, can produce parts with higher mechanical performance. This paper reports the shape optimization problem of a suspension control arm to be produced by additive manufacturing with fiber reinforcement, using finite element analysis. First, the current material, loading conditions and constraints to which the control arm is subjected were determined, considering its traditional design. Then, a numerical model of the part was developed considering its current material and shape to obtain the total deformation and von Mises stress distributions. Afterwards, the new material model was defined, and the shape optimization was performed with the goal of maximizing stiffness. Finally, the results from the optimization process were validated by manufacturing and testing the part.