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Tema 0. Introducción al pensamiento y a los movimientos sociales y políticos (2022-2023)
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Policy and Accounting Implications for Ocean Sustainability: Exploring the Ocean 100 Keystone Actors
No full textArtículo de revisiónVirdin et al. (Citation2021) explore the level of concentration of companies within and across eight ocean economy industries, and raise policy implications for ocean sustainability. These industries are offshore oil & gas, marine equipment and construction, seafood, container shipping, shipbuilding and repair, cruise tourism, port activities, and offshore wind
Saturdays of Science. An Experimental Learning and Training Scenario in CLIL and IBSE: A Case Study
No full textWe present a case study where the use of both Content and Language Integrated Learning (CLIL) and Inquiry-Based Science Education (IBSE) can be observed and studied as a hybrid methodology applied in a non-formal context in primary education. The context is the teaching of science in a Foreign Language (English) and the aim is to determine didactic strategies that are useful for improving teaching/learning processes. It is conducted in the non-formal context of science workshops, known as Saturdays of Science. 102 children in primary education attended the workshops, at which both the CLIL and the IBSE approaches were combined and which were supervised by 17 future teachers of primary education. The workshops were observed and analysed together with the changes introduced in the methodology and in the successive improvements to the teaching experience, examining the way in which they influenced the perceptions of the children and the future teachers. These results offer useful strategies for teachers in charge of CLIL teaching in primary education
Multimethod palaeointensity results from a rapidly emitted upper Miocene lava flow sequence in São Vicente (Cape Verde): new data for the African record
No full textWe present new radiometric ages and full-vector palaeomagnetic data from São Vicente Island, Cape Verde. Samples were obtained from a sequence of 11 flows. A K-Ar age determination was performed on the lowermost flow of the sequence, yielding an upper Miocene age of 6.07 ± 0.16 (2σ) Ma. Considering the normal polarity observed in all flows, the age of the sequence could be narrowed down to an interval between 6.03 and 6.23 Ma.
The mean palaeomagnetic direction of the studied sequence was compared with the expected direction, calculated from the African Apparent Polar Wander Path (5 Ma). While inclinations approximately agree, the palaeodeclination appears westwardly deviated by 26.5° ± 2.9°. Moreover, nearly no scatter of virtual geomagnetic poles around their mean value is observed and its comparison with the scatter observed in palaeomagnetic directions obtained from geomagnetic field model SHA.DIF.14k suggests that the sequence was very rapidly emplaced in only a few centuries. Thus, the obtained anomalous palaeomagnetic direction seems to reflect the effect of non-averaged secular variation, although a local vertical-axis counter-clockwise rotation of the sequence, cannot be entirely ruled out.
Thellier–Coe palaeointensity experiments on 66 specimens yielded 22 successful determinations and multispecimen (MS) palaeointensity experiments on 11 samples yielded 8 successful determinations. In the upper part of the sequence, Thellier–Coe determinations fail due to the presence of multidomain (MD) grains, but the MS method yields successful results in several of these flows, demonstrating that this method can provide reliable palaeointensity determinations on samples with a higher MD grain fraction. A mean palaeointensity BSV = (18.5 ± 1.9) µT is obtained from the joint analysis of the results from both methods. This value lies clearly below the present-day value BP = 33.1 μT. The virtual axial dipole moment (VADM = 4.3 × 1022 Am2), however, cannot be considered anomalous if compared to available upper Miocene–Pliocene data and represents a new high-reliability contribution to the very limited African palaeointensity database.This work was funded by project PID2019-105796GB-100/AEI/10.13039/501100011033 (Spanish Agencia Estatal de Investigación)
Compact climatization system for mechanical ventilation with heat recovery
No full textComunicación presentada en: XII Congreso Nacional y III Internacional de Ingeniería Termodinámica (12 CNIT), June 19- July 1, Madrid (Spain)Nearly zero energy (NZEB) or PASSIVHAUSS buildings are characterized by a very low energy consumption to meet the needs of air climatization (cooling and heating). Although in the design philosophy of these buildings, air conditioning and heating systems would be unnecessary, in some climatic regions, mainly due to user requirements, equipment such as geothermal or aerothermal heat pumps is usually installed. This type of house is conceived from the design stage to achieve high energy efficiency. The orientation of the building and distribution of windows and facades are studied in detail to reduce the building's energy demand by taking advantage of solar radiation in winter and avoiding overheating during summer. Another important aspect is the excellent insulation of the building envelope, reducing heat losses to the environment.The authors gratefully acknowledge the financial support provided by the Spanish Ministry of Science & Innovation under the I+D +i state program “Challenges Research Projects” (Ref. RTI2018-098900-B-I00). Diego Granados-López thanks grant PIRTU Program, ORDEN EDU/556/2019, for financial support
Why is the effect of recycled concrete aggregate on the compressive strength of self-compacting concrete not homogeneous? A bibliographic review
No full textLa presente revisión bibliográfica profundiza en cómo las características del Árido de Hormigón Reciclado (AHR) afectan al comportamiento resistente del Hormigón AutoCompactante (HAC) y cómo el efecto esperado del AHR puede alterarse por cambios en la composición del HAC. Se demuestra que, si la trabajabilidad del HAC se mantiene constante, la resistencia a compresión disminuye linealmente con el contenido de AHR, aunque este descenso será menor si el AHR procede del machaqueo de un hormigón de mayor resistencia. La disminución de la relación agua/cemento permite compensar esta pérdida de resistencia, aunque su valor debe permitir también mantener una adecuada trabajabilidad del HAC. La absorción de agua del AHR y su interacción con otros compontes incrementan la variabilidad del efecto del AHR. Debido a la gran cantidad de factores implicados en este comportamiento, es recomendable un estudio experimental del AHR y del HAC producido con él antes de su utilización.This literature review deepens in how the properties of Recycled Concrete Aggregate (RCA) affect the strength behavior of Self-Compacting Concrete (SCC) and how the expected effect of RCA can be modified by changes in its composition. It is demonstrated that, if the flowability of the SCC remains constant, the compressive strength decreases linearly with the RCA content, although this decrease is lower if the RCA is obtained from the crushing of a concrete with higher strength. The decrease of the water-to-cement ratio allows compensating this loss of strength, although its value should also allow keeping a suitable flowability. The water absorption of RCA and its interaction with other components of the mix increase the variability of the effect of RCA. Therefore, due to the large number of factors involved in this behavior, it is recommended to experimentally study the RCA and the SCC produced with it before its use.El presente trabajo ha sido financiado por el Ministerio de Ciencia e Innovación (MCINN), la Agencia Estatal de Investigación (AEI) y el Fondo Europeo De Desarrollo Regional (FEDER) [código ayuda FPU 17/03374]; la Junta de Castilla y León (JCyL) y el Fondo Europeo De Desarrollo Regional (FEDER) [código proyecto UIC-231; BU119P17]; la iniciativa de empleo juvenil de la Junta de Castilla y León y el Fondo Social Europeo (ESF) [código ayuda UBU05B_1274]; y, finalmente, la Universidad de Burgos (UBU) [código ayuda SUCONS, Y135.GI]. Los autores desean agradecer a todas estas instituciones su apoyo en este estudio
Effects of fiber material in concrete manufactured with electric arc furnace slag: Experimental and numerical study
No full textOver recent years, Electric Arc Furnace Slag (EAFS), a by-product of the steel-making industry, has been used as a replacement of natural aggregates to produce high-performance concrete. In EAFS concrete, fibers are normally added to improve post-cracking behavior, thereby prolonging the durability and range of applications of the composite. Despite the rise in its production, the mechanical performance of fiber-reinforced EAFS concrete is still poorly understood, posing important barriers to its daily use.
This paper aims to study the effect of fiber materials (steel and synthetic) on EAFS concrete performance. To do so, the paper proposes, firstly, an experimental campaign and, secondly, a numerical simulation to model the effect of fibers both in the pre-cracking and post-cracking stages. Importantly, for the numerical study, an in-house Finite Element (FE) code is developed using interface elements to capture crack propagation. The FE code uses, as input, data obtained in the experimental campaign and is validated against previously unseen experimental results. The overall framework gives important insights on how fibers improve the post-cracking behavior of EAFS concrete and the relevance of fiber material in the overall performance. The validated numerical tool can be used in the future to design EAFS fiber-reinforced concrete structures and therefore increase the applicability of such composite material.The authors wish to express their gratitude to the following entities for having funded this research work: the Spanish Ministries MCI, AEI, EU and ERDF [RTI2018-097079-B-C31; PID2020-113837RB-I00; 10.13039/501100011033]; the Junta de Castilla y León (Regional Government) and ERDF [UIC-231, BU119P17]; the Basque Government research group [IT1619-22 SAREN]; the University of Burgos [Y135.GI]
University Social Responsibility: the case of the Spanish Universities. Tools for their communication
No full textAño tras año, la Responsabilidad Social Universitaria (RSU) gana importancia
en las Universidades. Se presenta un estudio de revisión de la situación de las
universidades españolas que hacen RSU en 2020 y su evolución temporal a lo largo
de 10 años. Primero se revisa el concepto de RSU y se plantea una definición para,
seguidamente, realizar un estudio exploratorio en motores de búsqueda, directorios
y sitios web de universidades que analiza tipología, grupos de interés o la estructura
organizativa para gestionar la RSU, además de mostrar cómo se lleva a cabo su
comunicación y las memorias de Responsabilidad Social publicadas.Year after year, University Social Responsibility (USR) is gaining importance in universities. A study is presented to review the situation of Spanish universities that
carry out USR in 2020 and its evolution over 10 years. Firstly, the concept of USR is
reviewed and a definition is proposed, followed by an exploratory study in search
engines, directories and university websites that analysis typology, stakeholders or
the organizational structure to manage USR, as well as showing how communication and published reports of Social Responsibility are carried out