Inverse Modeling Problems in Task Enrichment for STEM Courses

Problem solving is considered as one of the most important topics in STEM (science, technology, engineering, and mathematics) education, and this is especially relevant when problems require modeling skills in order to be solved. Also, it should be noted that in many branches of science and technology, typical problems are posed in an inverse form. Then, combining both characteristics, the so-called inverse modeling problems deserve to be studied deeply, particularly in their potential for task enrichment. For those reasons, since 2016, a research project was carried out, by using inverse modeling problems to develop prospective teacher’s task enrichment skills. The results of this experience that took place in 2017 showed nine different groups of proposals where only few participants were very creative, whereas many others posed trivial problems or simply imitated examples analyzed previously. After that, a new research design was proposed during 2018 and implemented during the first months of 2019, with the aim of avoiding—or at least attenuating—those difficulties observed in the previous fieldwork. The new results showed interesting differences and few similarities when compared with the other experience. In this chapter, both experiences are analyzed, and lastly, findings and final conclusions are reported

The portrait in the bourgeois and aristocratic collections in Madrid during the 19th century: presence, meaning and narratives

El estudio de diferentes fuentes literarias, documentales (sobre todo inventarios) y gráficas (en especial fotografías) permite conocer los numerosos usos que el género del retrato tuvo en las colecciones de la burguesía y la nobleza durante el siglo XIX en Madrid. Se analizan tanto la variedad de narrativas en la disposición de los retratos históricos y de las efigies familiares en sus respectivos domicilios particulares como los diversos significados que ambos tipos de imágenes tuvieron. Además, estas prácticas se ponen en relación con las sucesivas iniciativas llevadas a cabo durante toda esta centuria desde instituciones como el Museo del Prado.The study of different literary, documentary (mainly inventories) and graphic sources (especially photographs) allows us to know the numerous uses that the portrait as a genre had in the collections of the bourgeoisie and aristocracy during the 19th century in Madrid. The variety of narratives in the disposition of historical portraits and the families’ effigies in their residences are analyzed, as well as the countless meanings that both types of images had and their relationships with the different initiatives carried out during that period by institutions such as the Museo del Prado

Performance Improvement Techniques for Photovoltaic Systems in Qatar: Results of First year of Outdoor Exposure

AbstractThe state of Qatar has established firm renewable energy deployment targets for the next decade, using primarily solar photovoltaic technologies.Qatar, in the Arabian Peninsula, is in the MENA Region, where the solar resource is fairly abundant, but local environmental conditions are challenging, particularly, high ambient temperatures all-year round, a dusty atmosphere due to high aerosol content, and water scarcity, which impact negatively on PV system performance and reliability.The Solar Test Facility (STF) at the Qatar Science & Technology Park (QSTP) was founded in 2012 for the main purpose of contributing to the achievement of Qatar's sustainable energy technology deployment targets. STF provides scientific and technical capabilities for testing and evaluation of solar technologies under the specific local climate conditions.This paper presents the results of outdoor exposure of a specific model of multicrystalline silicon (mc-Si) photovoltaic (PV) modules after their first complete year of operation at STF. The impact of module cleaning frequency, use of commercial anti- soiling coatings and module mounting on either fixed, one-axis-tracking or two-axis-tracking systems was studied.These results give some indication of the next steps to be taken and the solutions that would eventually work for the improvement of both the energy yield and the durability of PV systems deployed in this region

Uncertainty Analysis in the Inverse of Equivalent Conductance Method for Dealing with Crosstalk in 2-D Resistive Sensor Arrays

2-D resistive sensor arrays (RSAs) appear in many applications to measure physical quantities in a surface. However, they suffer from a crosstalk problem when the simplest configuration is used to address a row-column. Thus, the value of a single cell cannot be measured directly. Several hardware solutions have been proposed to solve it totally or partially but all of them make the circuit more complex. In a previous paper we proposed an innovative numerical solution to eliminate crosstalk after a complete scan of the matrix, which is named in this paper as Inverse of Equivalent Conductance Method (IECM). In the current study, we have analyzed the implications of the method for the uncertainty of the calculated cell resistance by first deriving the sensitivity of the solution and then applying uncertainty propagation theory. The theoretical results have been tested in simulated arrays and in a real 6x6 RSA with known values of resistances with good agreement. The uncertainty analysis is able to predict which values are reliable. In general, the lowest resistances of the array are better solved by IECM as expected. In addition, it is also shown that IECM has the potential to be adapted to other hardware configurations that reduce crosstalk, helping to overcome some of its limitations. IEE

Spatio-temporal variation of surface soil hydraulic properties under different tillage and maize-based crop sequences in a Mediterranean area

Aims: The surface crust formed by the drop impact of rainfall and/or irrigation is a prevalent characteristic in many Mediterranean soils. However, the temporal variation of soil hydraulic properties induced by surface crust during the high-frequency irrigation has rarely been investigated. Methods: Beerkan infiltration tests in conjunction with the BEST method were used to investigate the effects of surface crusting on the spatio-temporal variation of saturated soil hydraulic conductivity (Ks, mm s−1), sorptivity (S, mm s−0.5), mean pore size (r, mm), number of effective pores per unit area (N, m−2) in Agramunt, NE Spain. Results: In response to autumn tillage, intensive tillage (IT) increased Ks and S due to higher r and N, but both declined after 60 days. Reduced tillage (RT), maintained comparable Ks and S values, despite having a lower N value. After the spring tillage, both IT and RT developed crusted layers, resulting in decreased Ks, S and N. Long-term no-tillage (NT) showed an increasing trend of Ks and S over time, except for the last sampling. Spatial variation (i.e., between the rows, B-row vs. within the row of crops, W-row) of Ks and S was found, and non-crusted soils (W-row) had consistently higher Ks and S than crusted soils (B-row). Conclusions: Conservation tillage i.e., RT and NT improve the surface soil structure and reduce the risk of crust development. Surface cover by crops may help to prevent crust formation within the row of crops, improving soil hydraulic conductivity

Branded content aimed at Generation Z in the luxury fashion sector: Gucci and metaverse

El sector de la moda de lujo está marcado por la entrada al mercado de la generación Z. Estos jóvenes están redefiniendo la industria, reclamando a las marcas la aportación de valor a la sociedad. Una de las firmas destacadas en este sector es Gucci, cuya estrategia comunicativa es una muestra de la reorientación hacia este nuevo target. El objetivo de este trabajo es analizar la interrelación entre los recientes contenidos de marca de Gucci y las preferencias de la generación Z como consumidores, investigando, entre otros contenidos, las acciones de advergaming de Gucci en el metaverso. A través de un análisis cualitativo con una muestra de doce casos, se estudia a Gucci desde las perspectivas de persona, producto, organización y símbolo, siguiendo el modelo de identidad de marca de Aaker (2002) y la propuesta de Carcavilla y Aguirre (2022). Los resultados ilustran la conexión de estos cuatro aspectos presentes en los contenidos de marca de Gucci con valores de la generación Z como la diversidad o la innovación. La marca se dirige al consumidor de la generación Z en su comunicación mediante embajadores de marca, colaboraciones con otras marcas y plataformas del metaverso. Gucci ha sabido adaptarse al ambiente cambiante del sector de la moda de lujo actual, dando respuesta a las preocupaciones de un nuevo perfil de público y apostando por lo digital y la innovación.The luxury fashion sector is marked by generation Z’s entry into its market. These youngsters are redefining the industry, demanding brands’ contribution to society. One of the leading firms in this sector is Gucci, whose communication strategy is an example of reorientation towards this new target. This article aims at analyzing the conncetion between Gucci’s recent branded content and Generation Z’s consumer preferences by investigating, among other contents, Gucci’s advergaming actions in the metaverse. Through a quantitative/qualitative analysis with a sample of twelve cases, Gucci is studied from person, product, organization and symbol perspectives, following Aarker’s (2002) brand identity model and Carcavilla & Aguirre (2022) proposal. The results illustrate the connection of these four aspects present in Gucci’s brand content with Generation Z values such as diversity and innovation. The brand targets the Gen Z consumer in its communication through brand ambassadors, collaborations with other brands and metaverse platforms. Gucci has been able to adapt to the changing environment of the current luxury fashion sector, responding to the concerns of a new audience profile and betting on digital and innovation