Didactic strategies for comprehension and learning of structural concepts

p. 926-937In previous papers we have established the convenience of formulating educational strategies at the university level for both disciplines: Civil Engineering and Architecture, which involves academic topics of mutual interest by means of shared practices. As a particular matter of this approach, the application of physical experimental models is considered of special usefulness, in order to understand in better ways the performance of materials and structural systems. Several strategies of selection and development of such physical models will be discussed in this work, considering as a first step, the establishment of its correspondence with the different levels of structural complexity studied in curriculum plan: statics, strength of materials and structural design, among others. This task constitutes a part of the work program of the Laboratory of Structural Models, which is an academic project that develops and applies different didactic prototypes to structure courses in the Universidad Autónoma Metropolitana, campus Azcapotzalco, in Mexico City, project we have already presented in recent forums. Two different modes of application are implemented in classroom sessions and in structures workshop: the devices for functional demonstration of typical cases of structural work as well as the experimentation with student's own designs of destructible models where certain typologies are tested up to its failure limit. The first one allows teachers to explain adequately the theoretical principles and formulas (that usually are expressed on the blackboard) by means of didactic models identified in accordance to specific cases of the curriculum on variable level of complexity. This kind of practice allows the students of architecture and civil engineering to realize in better ways the possibilities of use and application of the different structural typologies. Such experimental models are part of more than fifty devices of the Laboratory's catalog. In the same sense, the possibility of observation of structural work of their own architectural designs, allows future professionals to achieve a better conception of the structural solutions that affect positively their designs. Based on specific predefined guides, the students develop their own architectural-structural projects and subject them to diverse loads, observing their behavior under the influence of variable stresses leading up the experiment to its last resistance. From both experiences a significant learning is obtained for the student's formation and training, who will be capable in his future professional work to use better tools of comprehension of the structural concepts applied to architecture as well as of increasing his conscience of the benefits and convenience of multidisciplinary work.Moreno, C.; Abad, A.; Gerdingh, JG.; Garcia M., C.; Gonzalez C., O. (2010). Didactic strategies for comprehension and learning of structural concepts. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/695

Direct Marketing: Theoretical delimitation and impact on consumer buying behavior

Direct marketing has become one of the most important communication tools for marketers. Direct marketing activities' budget is even higher than that for traditional advertising mass media, such as TV. However, there is not a single definition. On the contrary, several definitions have emerged in the literature. In this work, we establish a theoretical delimitation for direct marketing concept from those different perspectives analysed in marketing literature. In addition, an empirical analysis is presented in order to know if (really) direct marketing activities affect consumer buying behavior. From the results, key managerial implications are extracted in order to improve and optimise marketers' communicational budget

Generative adversarial networks for data-scarce spectral applications

Generative adversarial networks (GANs) are one of the most robust and versatile techniques in the field of generative artificial intelligence. In this work, we report on an application of GANs in the domain of synthetic spectral data generation, offering a solution to the scarcity of data found in various scientific contexts. We demonstrate the proposed approach by applying it to an illustrative problem within the realm of near-field radiative heat transfer involving a multilayered hyperbolic metamaterial. We find that a successful generation of spectral data requires two modifications to conventional GANs: (i) the introduction of Wasserstein GANs (WGANs) to avoid mode collapse, and, (ii) the conditioning of WGANs to obtain accurate labels for the generated data. We show that a simple feed-forward neural network (FFNN), when augmented with data generated by a CWGAN, enhances significantly its performance under conditions of limited data availability, demonstrating the intrinsic value of CWGAN data augmentation beyond simply providing larger datasets. In addition, we show that CWGANs can act as a surrogate model with improved performance in the low-data regime with respect to simple FFNNs. Overall, this work highlights the potential of generative machine learning algorithms in scientific applications beyond image generation and optimization

Deep learning for the modeling and inverse design of radiative heat transfer

Deep learning is having a tremendous impact in many areas of computer science and engineering. Motivated by this success, deep neural networks are attracting increasing attention in many other disciplines, including the physical sciences. In this work, we show that artificial neural networks can be successfully used in the theoretical modeling and analysis of a variety of radiative-heat-transfer phenomena and devices. By using a set of custom-designed numerical methods able to efficiently generate the required training data sets, we demonstrate this approach in the context of three very different problems, namely (i) near-field radiative heat transfer between multilayer systems that form hyperbolic metamaterials, (ii) passive radiate cooling in photonic crystal slab structures, and (iii) thermal emission of subwavelength objects. Despite their fundamental differences in nature, in all three cases we show that simple neural-network architectures trained with data sets of moderate size can be used as fast and accurate surrogates for doing numerical simulations, as well as engines for solving inverse design and optimization in the context of radiative heat transfer. Overall, our work shows that deep learning and artificial neural networks provide a valuable and versatile toolkit for advancing the field of thermal radiatio

Evolution Of Fair Business Performance As A Tool Of Marketing In Spain

Although the distance communication systems have been developed in the last years thanks to the development of communication and information technologies, recent studies argue that simple ways of communication like fairs maintain and increase their weigh cause of their profitability. In this way the fairs represent an important communication platform, whose use is generalized in the all economic areas. The aim of this paper is analyze the evolution of fair business in Spain, in the period 2002-2009, to solve two important questions which revolve about the efficiency of this communication tool and its power to maintain and establish new business relationship. For this, this paper analyzes the main characteristics or indicators of fair business, such as number of celebrated events, areas of interest, number of exhibitors or the number of attendees, from the information of Spanish Association of Fairs

Agrobiodiversidad

En cuanto a agrobiodiversidad, el Perú mantiene una gran biodiversidad genética en tubérculos, leguminosas, granos andinos, cacao, tuberosas tropicales, entre otros. El Instituto Nacional de Innovación Agraria es el encargado de conservación de esta biodiversidad orientado a la seguridad alimentaria. Asimismo, hace una valoración de estas para reconocer su aptitud agronómica y su adaptación al cambio climático, ese reconocimiento es útil para la generación de nuevas variedades con mejores características

Tunable Thermal Emission of Subwavelength Silica Ribbons

The thermal properties of individual subwavelength objects, which defy Planck’s law, are attracting significant fundamental and applied interest in different research areas. Special attention has been devoted to anisotropic structures made of polar dielectrics featuring thicknesses smaller than both the thermal wavelength and the skin depth. Recently, a novel experimental technique has enabled the measurement of the thermal emissivity of anisotropic SiO2 nanoribbons (with thicknesses on the order of 100 nm), demonstrating that their emission properties can be largely tuned by adjusting their dimensions. However, despite the great interest aroused by these results, their rigorous theoretical analysis has remained elusive due to the computational challenges arising from the vast difference in the length scales involved in the problem. In this work, we present a systematic theoretical analysis of the thermal emission properties of these dielectric nanoribbons based on simulations within the framework of fluctuational electrodynamics carried out with the boundary element method implemented in the SCUFF-EM code. In agreement with the experiments, we show that the emissivity of these subwavelength structures can be largely tuned and enhanced over the thin-film limit. We elucidate that the peculiar emissivity of these nanoribbons is due to the very anisotropic thermal emission that originates from the phonon polaritons of this material and the properties of the waveguide modes sustained by these dielectric structures. Our work illustrates the rich thermal properties of subwavelength objects, as well as the need for rigorous theoretical methods that are able to unveil the complex thermal emission phenomena emerging in this class of systemsJ.J.G.E. was supported by the Spanish Ministry of Science and Innovation through an FPU grant (FPU19/05281). J.B.A. acknowledges financial support from the Ministerio de Ciencia, Innovacioń y Universidades (RTI2018-098452-B-I00). J.C.C. acknowledges funding from the Spanish Ministry of Science and Innovation (PID2020-114880GB-I00

“Inducción de la embriogénesis somática en hojas inmaduras de sacha inchi (plukenetia volubilis L.)”

With the objective of developing a suitable methodology for the sacha inchi (Plukenetia vo/ubilis L.) somatic embryogenic induction, explants of immature leaf of 25-26 mm were used, two study were evaluated, the first one consisted of the evaluation of the synchronization of the induction time, using 05 treatments with different concentrations of thidiazurón (0.000, 0.003, 0.005, 0.008, 0.010 mg/I), with base culture media of the mineral compounds M&S (1962) supplemented with Vit DKW, 2.0 mg/I 2,4-0, 2.0 g/I phytagel; the same media for the second study 12 treatments witch different cornbinations of two factors [citoquinina (thidiazurón) - times of induction] were evaluated. For the development of the somatic embryogenesis process and especially for the second study (MICE) three means of culture where used, media of induction of embryogenic callus, media of secondary growth of callus (MCSC) anda media of development of embroides (MDE). For the induction process of embryogenic callus of the first and second study, the explants were incubated in darkness, for the second study the secondary growth of callus the period of darkness was limited to 6 and 10 days respectively, to be cultivated aftermath in the culture media MEO for a time of 14 days in darkness and then submitted to light. The percentage of induction of callus evaluated in all the treatments of the first study demonstrates that up to 9 days of induction 100 % of callogenic reactivity exists, the growth of callus evaluated in all the treatments of the second study demonstrates that a proflt of average callus in 4.46 to 4.97 mg/day exists, the appearance of pro-embryonic globular stages of sacha inchi was confirmad in the T2, T4, T9 and T10, and the conformation of the first embryonic stage (globular stage) was confirmed in the T4. lt is necessary to mention that during the development of the process of somatic not embriogenic callus of creamy and crystalline thin irregular consistency were identified. The rhizogenesis as a product of the indirect organogenesis in the immature leaves was one of the most important observations of this investigation.Con el propósito de desarrollar una metodología adecuada para la inducción de la embriogénesis somática sacha inchi (Plukenetia volubilis L.), se emplearon explantes de hoja inmadura de 25-26 mm, desinfectados por inmersión con alcohol etílico de 70° bajo tres segundos continuado por una desinfección con 0.5 % de NaOCI por un intermedio de diez minutos. Se evaluaron dos ensayos, el primero consistió en la evaluación de la sincronización del tiempo de inducción, utilizando 05 tratamientos con diferentes concentraciones de thidiazurón (0.000, 0.003, 0.005, 0.008, 0.010 mgn), acompañado de un medio de cultivo base constituido por los compuestos minerales M&S (1962) suplementado con Vit DKW, 2.0 mg/I 2,4-D, 2.0 g/I phytagel; de igual manera para el segundo ensayo se evaluaron 12 tratamientos con diferentes combinaciones de dos factores [citoquinina (thidiazurón) -tiempos de inducción (días)]. Para el desarrollo del proceso de la embriogénesis somática y en particular para el segundo ensayo se utilizaron tres medios de cultivo, medio de inducción del callo embriogénico (MICE), Medio de crecimiento secundario de callos (MCSC) y un medio de desarrollo de embroides (MDE). Para el proceso de inducción del callo embriogénico del primer y el segundo ensayo los explantes fueron incubados en oscuridad, para el segundo ensayo el crecimiento secundario de callos se acondiciono a un periodo de oscuridad de 6 y 1 O días respectivamente, para luego ser cultivados en el medio de cultivo MEO por un lapso de 14 días en condiciones de oscuridad y luego sometidos a luz. El porcentaje de inducción de callos evaluado en todos los tratamientos del primer ensayo demuestra que a los 9 días de inducción existe un 100% de reactividad callogénica, el crecimiento de callo evaluado en todos los tratamientos del segundo ensayo demuestra que existe una ganancia de callo promedio en 3.86 a 4.99 mg/día, la aparición de estadios globulares pro-embrionarios de sacha inchi se manifestaron los tratamientos T2, T4, T9 y T10, y la conformación del primer estadio embrionario (estadio globular) se manifestó en el tratamiento T 4. Cabe mencionar que durante el desarrollo del proceso de embriogénesis somática se identificaron callos no embriogénicos de consistencia cremosa y cristalino delgado e irregular. La rhizogénesis como producto de la organogénesis indirecta en las hojas inmaduras fue una de las más importantes observaciones en este trabajo de investigación.Tesi

Programa de lectura interactiva para potenciar la comprensión lectora en estudiantes de cuarto grado de primaria

Últimamente la comprensión lectora en gran parte de la población estudiantil no es la más adecuada, según se evidencia en las diversas investigaciones que presentan resultados desfavorables que aluden a las deficientes estrategias de los estudiantes al comprender un texto. En este contexto el objetivo de esta investigación, fue aplicar un programa de lectura interactiva para potenciar la comprensión lectora en niños del cuarto grado de primaria, proponiendo estrategias metodológicas que atiendan a los tres niveles de comprensión lectora: literal, inferencial y crítica. Este estudio siguió un enfoque cuantitativo con diseño de investigación cuasi – experimental, con preprueba y posprueba. Esto contribuirá a que posteriormente, se puede hacer un análisis más detallado de las variables estructuradas para esta investigación. Después de la aplicación prevista en la siguiente investigación, se logrará obtener como resultado, que los estudiantes que participaron del programa de lectura interactiva establezcan claramente conclusiones a partir de lo leído, identifiquen ideas centrales y secundarias del texto y se fomente el dialogo acerca de lo leído