Análisis numérico por el método de elementos finitos de una conexión de un perfil de alma llena embebido en un elemento de concreto

Trabajo de Investigación TecnológicaAl considerarse importantes las uniones o conexiones en el ámbito estructural, por tratarse de elementos que aportan resistencia y estabilidad; que contribuyen a la transmisión de esfuerzos generados por diversas cargas actuantes, se ha buscado la manera de mitigar el daño severo que sufren las mismas, en razón al mal diseño y técnicas durante la construcción. Por la cual, se propone el desarrollo de una conexión que incorpore flejes como enlace entre el perfil y el concreto, de modo que impidan la extracción del mismo, y con esto elaborar un modelo matemático a través del método de elementos finitos, que permita evaluar la longitud efectiva de empotramiento de una viga de alma llena embebida en un muro de concreto.RESUMEN INTRODUCCIÒN 2. LEVANTAMIENTO DE INFORMACIÓN 3. CONCLUSIONES 4. RECOMENDACIONES BIBLIOGRAFÍAPregradoIngeniero Civi

A Synergic Application of High-Oxygenated E-Fuels and New Bowl Designs for Low Soot Emissions: An Optical Analysis

[EN] Synthetic fuels significantly reduce pollutant emissions and the carbon footprint of ICE applications. Among these fuels, oxymethylene dimethyl ethers (OMEX) are an excellent candidate to entirely or partially replace conventional fuels in compression ignition (CI) engines due to their attractive properties. The very low soot particle formation tendency allows the decoupling of the soot-NOX trade-off in CI engines. In addition, innovative piston geometries have the potential to reduce soot formation inside the cylinder in the late combustion stage. This work aims to analyze the potential of combining OMEX with an innovative piston geometry to reduce soot formation inside the cylinder. In this way, several blends of OMEX-Diesel were tested using a radial-lips bowl geometry and a conventional reentrant bowl. Tests were conducted in an optically accessible engine under simulated EGR conditions, reducing the in-cylinder oxygen content. For this purpose, 2-colour pyrometry and high-speed excited state hydroxyl chemiluminescence techniques were applied to trace the in-cylinder soot formation and oxidation processes. The results confirm that increasing OMEX in Diesel improves the in-cylinder soot reduction under low oxygen conditions for both piston geometries. Moreover, using radial lips bowl geometry significantly improves the soot reduction, from 17% using neat Diesel to 70% less at the highest OMEX quantity studied in this paper.This work has been partially funded by Universitat Politècnica de València through the program of access contracts for PhD research staff in Research Structures of the Universitat Politècnica de València with reference PAID-10-22. The presence of Cinzia Tornatore at Universitat Politècnica de València was funded by the Short Term Mobility (STM) Program of the Italian National Research Council.Pastor, JV.; Micó, C.; De Vargas Lewiski, F.; Tejada-Magraner, FJ.; Tornatore, C. (2023). A Synergic Application of High-Oxygenated E-Fuels and New Bowl Designs for Low Soot Emissions: An Optical Analysis. Applied Sciences. 13(14). https://doi.org/10.3390/app13148560131

Simultaneous high-speed spectroscopy and 2-color pyrometry analysis in an optical compression ignition engine fueled with OME X -diesel blends

[EN] E-fuels are a very attractive way for improving the well-to-wheel emissions of CO 2 in internal combustion engines. In the particular case of compression ignition engines, the Oxymethylene dimethyl ether (OME X ), an e-fuel with nearly soot-free combustion under mixing-controlled conditions, is a good candidate for the replacement of fossil fuels. However, the Lower Heating Value of OME X is nearly half of the diesel fuel, which means that much longer injection durations are required in the real engine. In addition, the very low viscosity and lubricity of OME X can damage the injection system if used pure, but it can be an interesting fuel when blended with conventional diesel. Thus, the main objective of this paper is to evaluate the potential of OME X -diesel blends to bypass these OME X limitations whilst keeping low soot formation trends. For this purpose, a single cylinder optical diesel engine at part load was employed. The soot production for the different fuel blends was analyzed by applying three different high-speed imaging techniques: natural luminosity, flame spectroscopy and 2-color pyrometry. Natural luminosity analysis showed that the flame light intensity scales with diesel fraction up to 30% of diesel in the blend. The spectroscopy analysis has revealed that soot formation of OME X fuel is almost null. When blended with diesel at 50%, although soot formation is still lower than for pure diesel, higher soot levels are obtained in the last stages of the cycle as a consequence of the longer injections required.This work was partially funded by Generalitat Valenciana through the Programa Santiago Grisola (GRISOLIAP/2018/142) program.Pastor, JV.; García Martínez, A.; Micó, C.; De Vargas Lewiski, F. (2021). Simultaneous high-speed spectroscopy and 2-color pyrometry analysis in an optical compression ignition engine fueled with OME X -diesel blends. Combustion and Flame. 230:1-13. https://doi.org/10.1016/j.combustflame.2021.111437S11323

Multi-regression analysis to enhance the predictability of the seismic response of buildings

Several methodologies for assessing seismic risk extract information from the statistical relationship between the intensity of ground motions and the structural response. The first group is represented by intensity measures (IMs) whilst the latter by engineering demand parameters (EDPs). The higher the correlation between them, the lesser the uncertainty in estimating seismic damage in structures. In general, IMs are composed by either a single (scalar-based IMs) or a group of features of both the ground motion and the structure (vector-valued IMs); the latter category provides higher efficiency to explain EDPs when compared to the first one. This paper explores how to find new vector-valued IMs, which are highly correlated with EDPs, by means of multi-regression analysis. To do so, probabilistic nonlinear dynamic analyses have been performed by considering a seven-story reinforced concrete building as a testbed. At a first stage, 30 scalar-based IMs have been correlated with 4 EDPs (i.e., 120 groups of IM-EDP pairs have been studied). Afterwards, the structural responses have been classified as elastic, inelastic and a combination of both. It has been analyzed how efficiency behaves when making these classifications. Then, 435 vector-valued IMs have been created to enhance the predictability of the scalar EDPs (i.e., 1740 groups of IM-EDP pairs have been analyzed). Again, the most efficient IMs have been identified. Sufficiency, which is another statistical property desired in IMs, has also been examined. Results show that the efficiency and sufficiency to predict the structural response increase when considering vector-valued IMs. This sophistication has important consequences in terms of design or assessment of civil structures.This research has been partially funded by the European Regional Development Fund (ERDF) of the European Union (EU), through project with reference EFA158/16/POCRISC (INTERREG/POCTEFA. EU) and by the Spanish Research Agency (AEI) of the Spanish Ministry of Science and Innovation (MICIN) through project with reference: PID2020-117374RB-I00/AEI/10.13039/501100011033. The support of these institutions is highly recognized and acknowledged. Yeudy F. Vargas-Alzate has been granted an Individual Fellowship (IF) in the research grant program of the Marie Sklodowska-Curie Actions (MSCA), European Union/European (H2020-MSCA-IF-2017) No 799553. This author is deeply grateful to this institution.Peer ReviewedPostprint (published version

Seismic risk assessment using stochastic nonlinear models

The basic input when seismic risk is estimated in urban environments is the expected physical damage level of buildings. The vulnerability index and capacity spectrum-based methods are the tools that have been used most to estimate the probability of occurrence of this important variable. Although both methods provide adequate estimates, they involve simplifications that are no longer necessary, given the current capacity of computers. In this study, an advanced method is developed that avoids many of these simplifications. The method starts from current state-of-the-art approaches, but it incorporates non-linear dynamic analysis and a probabilistic focus. Thus, the method considers not only the nonlinear dynamic response of the structures, modeled as multi degree of freedom systems (MDoF), but also uncertainties related to the loads, the geometry of the buildings, the mechanical properties of the materials and the seismic action. Once the method has been developed, the buildings are subjected to earthquake records that are selected and scaled according to the seismic hazard of the site and considering the probabilistic nature of the seismic actions. The practical applications of the method are illustrated with a case study: framed reinforced concrete buildings that are typical of an important district, the Eixample, in Barcelona (Spain). The building typology and the district were chosen because the seismic risk in Barcelona has been thoroughly studied, so detailed information about buildings’ features, seismic hazard and expected risk is available. Hence, the current results can be compared with those obtained using simpler, less sophisticated methods. The main aspects of the method are presented and discussed first. Then, the case study is described and the results obtained with the capacity spectrum method are compared with the results using the approach presented here. The results at hand show reasonably good agreement with previous seismic damage and risk scenarios in Barcelona, but the new method provides richer, more detailed, more reliable information. This is particularly useful for seismic risk reduction, prevention and management, to move towards more resilient, sustainable cities.This research was funded by the research grant program Marie Sklodowska-Curie Actions (MSCA), European Union/European (H2020-MSCA-IF-2017) No 799553. This research was also partially funded by the Spanish Government’s Ministry of Economy and Competitiveness (MINECO) and by the European Regional Development Funds (ERDF) of the European Union (EU) through projects with references CGL2015-65913 -P (MINECO/ERDF, EU) and EFA158/16/POCRISC (INTERREG/POCTEFA. EU). The support of these institutions is highly recognized and acknowledged.Peer ReviewedPostprint (published version

New perspective in the design of quality management systems

This article aims to analyze the different trends and models of the current quality management systems, identifying areas of opportunity in these to establish proposals for care that give rise to a new management system, flexible, efficient and effective Supported by a system of sociotechnical work. The competitive climate in today's business has multiplied significantly in the face of the dynamics of change and the presence of ever shorter business cycles. It is a fact that in the last decades the market has been acquiring an increasing dynamism. Today, companies are developing in a more competitive national and international economy, with increasing demands for productivity, where market laws force them to deepen and change strategies and policies, to plan, create and innovate, to have a high degree of resilience and Sensitivity to anticipate future needs and to be able to survive and develop in a complex and increasingly competitive environment. In these times the markets are increasingly informed, so their expectations are increasingly demanding, for this reason is that quality becomes a differentiating element and at the same time the key factor of a company's lasting success

An optical investigation of Fischer-Tropsch diesel and Oxymethylene dimethyl ether impact on combustion process for CI engines

[EN] Synthetic fuels (E-fuels) have shown to be an interesting alternative to replace the fossil diesel fuel due to its CO2 reduction potential as well as for their capability to diminish the soot production and therefore for improving the soot-NOX trade-off in Compression Ignition engines. Thus, the main objective of this paper was to better understand the combustion process and the in-cylinder soot formation of two of the most popular E-fuels currently: Fischer-Tropsch (FT) diesel and Oxymethylene dimethyl ether (OMEX). To achieve this aim, a single cylinder optical CI engine with a commercial piston geometry was used. Thee optical techniques (Natural Luminosity-NL, OH* chemiluminescence and 2-color pyrometry) were applied to analyze the combustion evolution and quantify the soot formation at different loads (1.5, 4.5 and 7.5 bar IMEP). OMEX presented the largest injection duration due to the low LHV. For the NL analysis, OMEX showed the lowest light intensity for the three loads tested, indicating a very low soot production. Despite of the low NL intensity, it presented the highest OH* chemiluminescence signal, indicating a higher presence of near-stoichiometric zones due to the high amount of oxygen. Regarding FT diesel, it showed a combustion behavior similar to the commercial diesel. NL, OH* and 2-color technique analysis indicated that for the three conditions tested, FT diesel presented lower soot production and a faster soot oxidation than commercial diesel.This work was partially funded by Generalitat Valenciana through the Programa Santiago Grisolia (GRISOLIAP/2018/142) program.Pastor, JV.; García Martínez, A.; Mico Reche, C.; De Vargas Lewiski, F. (2020). An optical investigation of Fischer-Tropsch diesel and Oxymethylene dimethyl ether impact on combustion process for CI engines. Applied Energy. 260:1-12. https://doi.org/10.1016/j.apenergy.2019.114238S112260Benajes, J., García, A., Monsalve-Serrano, J., & Lago Sari, R. (2018). Fuel consumption and engine-out emissions estimations of a light-duty engine running in dual-mode RCCI/CDC with different fuels and driving cycles. Energy, 157, 19-30. doi:10.1016/j.energy.2018.05.144Dronniou, N., Kashdan, J., Lecointe, B., Sauve, K., & Soleri, D. (2014). Optical Investigation of Dual-fuel CNG/Diesel Combustion Strategies to Reduce CO2 Emissions. SAE International Journal of Engines, 7(2), 873-887. doi:10.4271/2014-01-1313Tanov, S., Wang, Z., Wang, H., Richter, M., & Johansson, B. (2015). Effects of Injection Strategies on Fluid Flow and Turbulence in Partially Premixed Combustion (PPC) in a Light Duty Engine. SAE Technical Paper Series. doi:10.4271/2015-24-2455Zha, K., Busch, S., Warey, A., Peterson, R. C., & Kurtz, E. (2018). A Study of Piston Geometry Effects on Late-Stage Combustion in a Light-Duty Optical Diesel Engine Using Combustion Image Velocimetry. SAE International Journal of Engines, 11(6), 783-804. doi:10.4271/2018-01-0230Omari, A., Heuser, B., Pischinger, S., & Rüdinger, C. (2019). Potential of long-chain oxymethylene ether and oxymethylene ether-diesel blends for ultra-low emission engines. Applied Energy, 239, 1242-1249. doi:10.1016/j.apenergy.2019.02.035Hao, B., Song, C., Lv, G., Li, B., Liu, X., Wang, K., & Liu, Y. (2014). Evaluation of the reduction in carbonyl emissions from a diesel engine using Fischer–Tropsch fuel synthesized from coal. Fuel, 133, 115-122. doi:10.1016/j.fuel.2014.05.025Kook, S., & Pickett, L. M. (2012). Liquid length and vapor penetration of conventional, Fischer–Tropsch, coal-derived, and surrogate fuel sprays at high-temperature and high-pressure ambient conditions. 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Progress in Energy and Combustion Science, 37(4), 503-523. doi:10.1016/j.pecs.2010.09.001Jiao, Y., Liu, R., Zhang, Z., Yang, C., Zhou, G., Dong, S., & Liu, W. (2019). Comparison of combustion and emission characteristics of a diesel engine fueled with diesel and methanol-Fischer-Tropsch diesel-biodiesel-diesel blends at various altitudes. Fuel, 243, 52-59. doi:10.1016/j.fuel.2019.01.107Abu-Jrai, A., Tsolakis, A., Theinnoi, K., Cracknell, R., Megaritis, A., Wyszynski, M. L., & Golunski, S. E. (2006). Effect of Gas-to-Liquid Diesel Fuels on Combustion Characteristics, Engine Emissions, and Exhaust Gas Fuel Reforming. Comparative Study. Energy & Fuels, 20(6), 2377-2384. doi:10.1021/ef060332aSchaberg, P., Botha, J., Schnell, M., Hermann, H.-O., Pelz, N., & Maly, R. (2005). Emissions Performance of GTL Diesel Fuel and Blends with Optimized Engine Calibrations. SAE Technical Paper Series. doi:10.4271/2005-01-2187Iannuzzi, S. E., Barro, C., Boulouchos, K., & Burger, J. (2016). Combustion behavior and soot formation/oxidation of oxygenated fuels in a cylindrical constant volume chamber. Fuel, 167, 49-59. doi:10.1016/j.fuel.2015.11.060Pellegrini, L., Marchionna, M., Patrini, R., Beatrice, C., Del Giacomo, N., & Guido, C. (2012). Combustion Behaviour and Emission Performance of Neat and Blended Polyoxymethylene Dimethyl Ethers in a Light-Duty Diesel Engine. SAE Technical Paper Series. doi:10.4271/2012-01-1053Zhu, R., Wang, X., Miao, H., Huang, Z., Gao, J., & Jiang, D. (2008). Performance and Emission Characteristics of Diesel Engines Fueled with Diesel−Dimethoxymethane (DMM) Blends. Energy & Fuels, 23(1), 286-293. doi:10.1021/ef8005228Härtl, M., Seidenspinner, P., Jacob, E., & Wachtmeister, G. (2015). Oxygenate screening on a heavy-duty diesel engine and emission characteristics of highly oxygenated oxymethylene ether fuelOME1. Fuel, 153, 328-335. doi:10.1016/j.fuel.2015.03.012Omari, A., Heuser, B., & Pischinger, S. (2017). Potential of oxymethylenether-diesel blends for ultra-low emission engines. Fuel, 209, 232-237. doi:10.1016/j.fuel.2017.07.107Ma, X., Ma, Y., Sun, S., Shuai, S.-J., Wang, Z., & Wang, J.-X. (2017). PLII-LEM and OH* Chemiluminescence Study on Soot Formation in Spray Combustion of PODEn-Diesel Blend Fuels in a Constant Volume Vessel. SAE Technical Paper Series. doi:10.4271/2017-01-2329Liu, H., Wang, Z., Zhang, J., Wang, J., & Shuai, S. (2017). Study on combustion and emission characteristics of Polyoxymethylene Dimethyl Ethers/diesel blends in light-duty and heavy-duty diesel engines. Applied Energy, 185, 1393-1402. doi:10.1016/j.apenergy.2015.10.183Lumpp, B., Rothe, D., Pastötter, C., Lämmermann, R., & Jacob, E. (2011). OXYMETHYLENE ETHERS AS DIESEL FUEL ADDITIVES OF THE FUTURE. MTZ worldwide, 72(3), 34-38. doi:10.1365/s38313-011-0027-zLiu, H., Wang, Z., Wang, J., & He, X. (2016). Improvement of emission characteristics and thermal efficiency in diesel engines by fueling gasoline/diesel/PODEn blends. Energy, 97, 105-112. doi:10.1016/j.energy.2015.12.110Chen, H., Su, X., Li, J., & Zhong, X. (2019). Effects of gasoline and polyoxymethylene dimethyl ethers blending in diesel on the combustion and emission of a common rail diesel engine. Energy, 171, 981-999. doi:10.1016/j.energy.2019.01.089Payri, R., De La Morena, J., Monsalve-Serrano, J., Pesce, F. C., & Vassallo, A. (2018). Impact of counter-bore nozzle on the combustion process and exhaust emissions for light-duty diesel engine application. International Journal of Engine Research, 20(1), 46-57. doi:10.1177/1468087418819250De Simio, L., & Iannaccone, S. (2019). Gaseous and particle emissions in low-temperature combustion diesel–HCNG dual-fuel operation with double pilot injection. Applied Energy, 253, 113602. doi:10.1016/j.apenergy.2019.113602Denny, M., Holst, F., Helmantel, A., Persson, H., Tunestål, P., & Andersson, Ö. (2019). Impact of closely-coupled triple-pilot and conventional double-pilot injection strategies in a LD diesel engine. Fuel, 246, 141-148. doi:10.1016/j.fuel.2019.02.101Pastor, J. V., García-Oliver, J. M., García, A., & Pinotti, M. (2016). Laser induced plasma methodology for ignition control in direct injection sprays. Energy Conversion and Management, 120, 144-156. doi:10.1016/j.enconman.2016.04.086Jakob, M., Hülser, T., Janssen, A., Adomeit, P., Pischinger, S., & Grünefeld, G. (2012). Simultaneous high-speed visualization of soot luminosity and OH∗ chemiluminescence of alternative-fuel combustion in a HSDI diesel engine under realistic operating conditions. Combustion and Flame, 159(7), 2516-2529. doi:10.1016/j.combustflame.2012.03.004Pastor, J. V., García-Oliver, J. M., García, A., Micó, C., & Möller, S. (2016). 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Improved intensity measures considering soil inelastic properties via multi-regression analysis

At certain depths, the elastic properties of the ground are not affected by seismic waves. However, as they reach the surface, the soil density decreases and so does its elastic limit. This means that the expected ground motion acting at the foundation of a structure cannot be adequately described without considering the inelastic response of the soil near the surface. Therefore, one of the key elements in characterizing the seismic response of civil structures is the site effect. These depend mainly on the parameters of the soil beneath the structure and the features of the ground motion acting at the depth, where non-linear effects are negligible. Therefore, the main objective of this paper is to find an intensity measure that incorporates the information provided by the soil profile under the structure and the ground motion acting at the bedrock level. Due to the random nature of both elements, a probabilistic framework using Monte Carlo simulation has been developed to analyze this problem. For this purpose, random soil profiles have been generated to obtain a representative sample of likely scenarios of the study area. A large database of Colombian ground motion records has been used to model the seismic hazard. Finally, power functions capable of relating the input variables to the dynamic response of a large set of reinforced concrete structures have been derived by considering multi-regression analysis. It has been observed that, in several cases, intensity measures extracted from the displacement spectrum appear in the mathematical arrangements. These functions could be used to improve the efficiency of seismic risk prediction at the urban level.This research has been funded by the Spanish Research Agency (AEI) of the Spanish Ministry of Science and Innovation (MICIN) through the projects with references: PID2020-117374RB-I00/AEI/10.13039/501100011033 and TED 2021-132559B-I00—J-02970.Peer ReviewedPostprint (published version

独立阅读的乐趣：对其测量的建议

Diversas investigaciones corroboran la relación entre lectura independiente y desempeño académico; sin embargo, considerar únicamente que a mayor lectura independiente mayor rendimiento académico resulta una perspectiva reduccionista. Analizar el componente de placer que se encuentra implícito en la lectura independiente permite desentrañar la relación entre estudiante y objeto de lectura desde las mediaciones que devienen en la construcción de conocimiento, empatía, creatividad y criticidad; con lo cual se convierte en un paso necesario en la problematización de las relaciones entre lectura y desempeño académico. Se realizó un análisis secundario de los datos obtenidos en un proyecto de investigación desarrollado para explorar los hábitos de lectura en el estudiantado de una Universidad a Distancia y utilizando métodos estadísticos multivariados, se construyó un Índice de Placer hacia la Lectura Independiente (IPLI). La metodología estadística usada permitió identificar en la construcción del índice dos dimensiones una individual y una colectiva, permitiendo evidenciar las hipótesis iniciales acerca de la confluencia de elementos de resignificación individual y elementos de identificación empática con la otredad, factores que intervienen en igual importancia en el placer que expresa un individuo al leer. Establecer el nivel de placer hacía la lectura en estudiantes que ingresan a la universidad, especialmente en el caso de los estudiantes a distancia, permite a los docentes y directivos pensar en estrategias pedagógicas y de intervención que fortalezcan el hábito de leer en los estudiantes, lo cual, se espera redunde en el buen desempeño académico y en la formación para la vida laboral de los individuos.Several investigations corroborate the relationship between independent reading and academic performance; however, considering only that the higher the independent reading the higher the academic performance, it is a reductionist perspective. Analyzing the pleasure component that is implicit in independent reading allows us to problematize the relationship between student and reading object from the mediations that result in the construction of knowledge, empathy, creativity, and criticality; with which it becomes a necessary step in the problematization of the relationships between reading and academic performance. A secondary analysis of the data obtained in a research project developed to explore reading habits in students of a Distance University was carried out and using multivariate statistical methods an Independent Reading Pleasure Index (IPLI) was constructed. The statistical methodology used, allowed us to identify in the Index, two dimensions; one individual and other one collective evidencing the initial hypotheses about the confluence of elements of individual resignification and the emphatic identification with otherness, factors that intervene with equal importance in the individual pleasure expressed when reading. To stablish the level of pleasure in reading in students that start studies at university, allows teachers and managers to think about pedagogical strategies of intervention to strengthen the habit of reading in students. It is expected that; those interventions allow improve the academic performance and training for the working life on individuals.Несколько исследований подтверждают взаимосвязь между самостоятельным чтением и успеваемостью, однако, считать, что чем больше самостоятельного чтения, тем выше успеваемость - это упрощенная точка зрения. Анализ компонента удовольствия, который подразумевается в самостоятельном чтении, позволяет нам раскрыть отношения между студентом и объектом чтения с точки зрения посредников, которые приводят к построению знаний, эмпатии, креативности и критичности; таким образом, это становится необходимым шагом в осмыслении взаимосвязи между чтением и успеваемостью. Был проведен вторичный анализ данных, полученных в рамках исследовательского проекта, разработанного для изучения привычек чтения студентов университета дистанционного обучения, и с помощью многомерных статистических методов был построен индекс удовольствия от самостоятельного чтения (IPLI). Использованная статистическая методология позволила нам выделить два измерения в построении индекса, индивидуальное и коллективное, что позволило нам продемонстрировать первоначальные гипотезы о слиянии элементов индивидуальной переподчинения и элементов эмпатической идентификации с инаковостью, факторов, которые вмешиваются в равной степени в удовольствие, которое человек выражает при чтении. Установление уровня удовольствия от чтения у студентов, поступающих в университет, особенно в случае заочников, позволяет преподавателям и директорам задуматься о педагогических и интервенционных стратегиях, укрепляющих привычку к чтению у студентов, что, как можно надеяться, приведет к хорошей успеваемости и подготовке к трудовой деятельности.不同的调查研究证实了独立阅读和学业成绩之间的关系；然而，仅考虑独立阅读越高，学业成绩越高，这还只是一种还原论的观点。分析独立阅读中隐含的快乐成分使我们能够从导致知识建构、同理心、创造力和批判性的中介中解开学生与阅读对象之间的关系；这一分析成为解决阅读和学业成绩之间关系问题化的必要步骤。我们对一个研究项目中获得的数据进行了二次分析，该项目旨在探索远程大学学生的阅读习惯，并使用多元统计方法构建了独立阅读快乐指数 (IPLI)。所使用的统计方法允许在构建指数时确定两个维度，个人维度和集体维度，从而可以证明关于个人重新定义的要素和移情认同与他者的要素汇合的初步假设，这些因素在个人阅读时所表达的快乐中具有同等重要性。帮助刚进入大学的学生建立阅读兴趣，让教师和管理人员能够考虑加强学生阅读习惯的教学和干预策略，这些干预措施可以提升个人的学习成绩和工作方面的培训

Simulación de la aplicación de un aislante térmico natural en un deshidratador solar indirecto

Thermal insulators are of great significance in equipment where temperature is one of the main factors for its proper functioning. Over the years, different types of synthetic insulators have been manufactured. However, as it is well known that fossil fuels are becoming scarce with the time, humanity has seen the need to investigate sustainable materials with equal or improved characteristics than synthetic ones, leading to the investigation of natural thermal insulators. In the present project the effects on the application of a thermal insulation 100% made from natural fiber placed in an indirect solar fruit dehydrator is investigated. In this context, equipment with and without thermal insulation was computer simulated in order to compare the internal temperatures and thus, determine the efficiency and applicability of the thermal insulator. It was concluded that the natural fiber thermal insulator presents favorable results as the increase on the internal temperature by 20% which directly influences the drying time. In this way, it was established that the natural thermal insulation can be used in an indirect solar dehydrator reducing the drying time, increasing its efficiency and contributing to the environment.Los aislantes térmicos son de gran importancia en equipos en los que la temperatura es uno de los factores fundamentales para su buen funcionamiento. Con el pasar de los años se han fabricado distintos tipos de aislantes sintéticos, pero a medida que los combustibles fósiles comienzan a escasear, la humanidad se ha visto en la necesidad de investigar sobre otros materiales que presenten características iguales o superiores a las de los sintéticos, lo que da paso a la investigación de los aislantes térmicos naturales. En el presente proyecto se investigan los efectos de la aplicación de un aislante térmico de origen 100 % natural en un equipo deshidratador solar indirecto para secado de frutas. En este contexto se simularon equipos con y sin aislamiento térmico con el fin de comparar las temperaturas internas y, de esta manera, determinar la eficiencia y aplicabilidad del aislante térmico. Se concluyó que el aislante térmico presenta resultados favorables como, por ejemplo, el aumento de la temperatura interna en un 20 %, lo que influye de forma directa en el tiempo de secado. De esta manera, se estableció que el aislante térmico natural puede utilizarse en un deshidratador solar indirecto y reducir de esta forma el tiempo de secado, así como aumentar su eficiencia y contribuir con el medio ambiente.