1,515 research outputs found
Resilient Strategies for Internet-Based Education: Investigating Engineering Students in the Canary Islands in the Aftermath of COVID-19
[EN] The COVID-19 pandemic has brought about notable changes in the education sector, specif-
ically the shift towards online learning. This study examined the experiences of 124 engineering
students in the Canary Islands, an EU ultra-peripheral region, as they adapted to online education
during the pandemic. A comprehensive survey assessed students’ experiences in five key dimensions,
including satisfaction with traditional face-to-face learning, perceptions of the engineering depart-
ment’s transition to online learning, module-specific adaptations, personal adaptation strategies,
and the adaptation of teaching staff. The study’s methodology involved statistical analyses using
Microsoft Excel v16.0 and SPSS 27 tools to identify patterns and draw conclusions. The findings
indicate a nuanced landscape. Students demonstrated strong technological literacy and readiness for
online learning. However, they expressed concerns about educators’ digital proficiency and perceived
a decline in educational quality. These results emphasize the critical need for sustainable, adaptable,
and inclusive educational strategies, particularly in regions like the Canary Islands that face unique
challenges. The implications of the study have broader relevance to digital education. It is essential
to note the need for educators to receive comprehensive training in digital tools and methodologies
to improve the quality of online learnin
Modelo local de simulación de nivel de napa freática en la Depresión del Salado
p.155-158A partir del esquema clásico del balance hidrológico seriado se elaboró un modelo que estima la variación mensual del nivel de napa freática a partir de las características físicas del suelo y de la precipitación y la evapotranspiración potencial mensuales. El modelo se ajustó tomando como referencia las series mensuales de las localidades de Dolores (1942-1977) y Chascomús (1945-1951). Pudo comprobarse que, tomando como partida los datos observados, el modelo reproduce ajustadamente el comportamiento de la napa durante 7 años, apartándose luego gradualmente. Por lo que posee capacidad para interpolar largos períodos faltantes en las series de observaciones, problema que se presenta frecuentemente con los registros de napa freática. El estudio se realizó para localidades situadas en la Depresión del Salado, lo que determina que el modelo sea de validez local ya que no se consideró el aporte de agua desde otras localidades debido a la escasa pendiente de la zona y a las características de drenaje de los suelos, las cuales determinan un movimiento vertical lento del agua debido a la presencia de horizontes de escasa permeabilidad
Cronología de inundaciones y sequías en el noreste de la provincia de Buenos Aires 1911 - 1989
p.241-249El objetivo del presente trabajo consistió en reproducir, por medio del balance hídrico del suelo, la cronología de inundaciones y sequías del Noreste de la Provincia de Buenos Aires y evaluar si la misma pudo darse dentro de un régimen de lluvias completamente aleatorio o si requirió que el mismo contuviera componentes determinísticas, como ciclos, periodicidades o saltos climáticos para producirse. Muchas de las series de datos mensuales empleadas presentaron una leve tendencia positiva, aunque en ningún caso resultó significativa debido a la alta variabilidad natural del fenómeno, que también puede ser interpretado como un salto de los promedios 1971-89 con respecto a los 1911-70, dado que tomados aisladamente ninguno de los dos períodos presenta tendencia. El análisis espectral reveló algunos picos levemente significativos y cuasi significativos, pero con una contribución muy pequeña a la variancia total, lo que hace descartar los efectos de procesos periódicos o cuasi periódicos. El estudio de rachas reveló que las de precipitación son completamente aleatorias y ráramente exceden los tres meses de duración, mientras que las de humedad del suelo muestran un proceso markoviano con alta persistencia pudiendo llegar a los 18 meses de extensión. Comparado con el período 1911 -70, el período 1971 -89 presentó un predominio de las rachas húmedas
Maneuver Optimization for Simultaneous Airspeed Calibration and Wind Estimation
[EN] The purpose of this work is to optimize systematically the maneuver required to identify the wind and calibrate the airspeed sensor of a subsonic aircraft using a GPS method. The optimization is based on sensitivity analyses that require a considerable number of flight simulations. To face this challenging computational effort, we adapted and parallelized a particle swarm optimization algorithm. We also introduced a new formulation of the sensor model in the Bernstein form. The results show stability using the selected formulation and bring out non-obvious aliasing and precision loss effects that depend on the maneuver configuration. The knowledge of these effects allowed us to fine-tune the maneuver in order to improve the estimation's precision. Finally, we validated the method using the JSBSim flight simulator under calm and light turbulence conditions.S
An evaluation of the feasibility of electrostatic separation for physical soil washing
[EN] We present the first application of electrostatic separation for soil washing. Soil samples were collected from the PTE-containing area of La Cruz in Linares, southern Spain. Using a single-phase high-tension roll separator with voltages ranging from 20 kV to 41.5 kV, we achieved yield values between 0.69% and 9%, with high recovery rates for certain elements such as Zn, Cu, and Mo. SEM-EDX analysis revealed three particle types, including a non-conductive fraction composed of feldspar, a middling fraction composed of mica, and a conductive fraction consisting of PTE-bearing slag grains. Attributive analysis showed that 41.5 kV was the optimal voltage for maximizing PTE concentration. Overall, electrostatic separation is a promising approach for treating soils contaminated with PTEs, particularly in dry climate areas impacted by mining activities.S
A Discussion on the Effective Ventilation Distance in Dead-End Tunnels
[EN] Forcing ventilation is the most widely used system to remove noxious gases from a working
face during tunnel construction. This system creates a region near the face (dead zone), in which
ventilation takes place by natural diffusion, rather than being directly swept by the air current. Despite
the extensive use of this system, there is still a lack of parametrical studies discerning the main
parameters affecting its formation as well as a correlation indicating their interrelation. With this aim
in mind, computational fluid dynamics (CFDs) models were used to define the dead zone based on
the airflow field patterns. The formation of counter vortices, which although maintain the movement
of air hinder its renewal, allowed us to discuss the old paradigm of defining the dead zone as a very
low air velocity zone. Moreover, further simulations using a model of air mixed with NO2 offered an
idea of NO2 concentrations over time and distance to the face, allowing us to derive at a more realistic
equation for the effective distance. The results given here confirm the degree of conservativism of
present-day regulations and may assist engineers to improve ventilation efficiency in tunnels by
modifying the duct end-to-face distanc
Nanoscale zero-valent iron-assisted soil washing for the removal of potentially toxic elements
The present study focuses on soil washing enhancement via soil pretreatment with nanoscale zero-valent iron (nZVI) for the remediation of potentially toxic elements. To this end, soil polluted with As, Cu, Hg, Pb and Sb was partitioned into various grain sizes (500?2000, 125?500 and <125??m). The fractions were pretreated with nZVI and subsequently subjected, according to grain size, to Wet-High Intensity Magnetic Separation (WHIMS) or hydrocycloning. The results were compared with those obtained in the absence of nanoparticles.
An exhaustive characterization of the magnetic signal of the nanoparticles was done. This provided valuable information regarding potentially toxic elements (PTEs) fate, and allowed a metallurgical accounting correction considering the dilution effects caused by nanoparticle addition.
As a result, remarkable recovery yields were obtained for Cu, Pb and Sb, which concentrated with the nZVI in the magnetically separated fraction (WHIMS tests) and underflow (hydrocyclone tests). In contrast, Hg, concentrated in the non-magnetic fraction and overflow respectively, while the behavior of As was unaltered by the nZVI pretreatment. All things considered, the addition of nZVI enhanced the efficiency of soil washing, particularly for larger fractions (125?2000??m). The proposed methodology lays the foundations for nanoparticle utilization in soil washing operations.This work was supported by Project CTM2016-75894-P (MINECO). Carlos Boente obtained a grant from the “Formación del Profesorado Universitario” program, financed by the “Ministerio de Educación, Cultura y Deporte de España”. The authors thank the “Servicio Cientifico-Técnico de Medidas Magnéticas” of the University of Oviedo
Psychosocial and psychopathological characteristics of Spanish adolescents sample throw Youth Self-Report/11-18
En este estudio se analizan las competencias psicosociales y características psicopatológicas evaluadas por el YSR/11-18 (Achenbach y Rescorla, 2000, 2001) en una muestra de 961 adolescentes españoles de 13-18 años de edad. Los resultados encontrados indicaron que los varones puntúan de forma elevada en distintas actividades sociales y psicopatología externalizante, mientras que las mujeres presentan mayores puntuaciones en rendimiento en diferentes tareas y sintomatología internalizante. Los adolescentes de menor edad presentan puntuaciones más altas que los mayores en la participación en grupos y organizaciones, así como en la mayoría de las escalas sindrómicas del YSR/11-18, mientras que los se-gundos prefieren realizar actividades no deportivas y trabajos o tareas. Los alumnos de ESO y Bachillerato presentan más actividad en todas las com-petencias psicosociales que los de Ciclos Formativos, aunque éstos últimos superan a los primeros en la mayoría de las escalas sindrómicas. Los ado-lescentes sin relación de pareja puntuaron más alto en las competencias psicosociales que los que disfrutan de la misma, aunque éstos muestran más psicopatología que los primeros. Por último, realizar una actividad laboral (además de estudiar) no parece ser relevante a la hora de establecer diferencias respecto a las competencias psicosociales y a las escalas sin-drómicas.In this study we analyzed the psychosocial competences and psychopathological characteristics assessed by the YSR/11-18 in a sample of 961 Spanish adolescents from 13-18 years. The results indicated that men scored high in various social activities and externalized psychopa-thologies, while women have high scores for performance in different tasks and internalized symptoms. Younger adolescents showed higher scores than older ones in participation in groups and organizations, as well as in most of the YSR/11-18 syndromic scales, while older adolescent’s preferred no sports activities and works or tasks. Students at Compulsory Secondary Education and Non-Compulsory Secondary Education showed more activity than those in Vocational Training Cycles in all psychosocial competencies, but the latter overcame the first in most of the syndromic scales. Adolescents without romantic relation scored higher in the psycho-social competencies than those who enjoyed romantic relation, although the second ones showed more psychopathology than the first ones. Fi-nally, working (in addition to studying) did not seem to be relevant in determining differences regarding the psychosocial competencies and syndromic scales
Eutanàsia en animals de companyia : quan està justificada?
Treball presentat a l'assignatura de Deontologia i Veterinària Legal (21223
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