Escuela de Politécnica Superior

This study delves into the fascinating history of the destruction of the walls of Jericho as describedinthe biblical account in the book of Joshua. Over the last century, prominent archaeologistssuchasCarl Watzinger, John Garstang, Kathleen Kenyon, and Bryant Wood have excavatedthesite,confirming the existence of the ancient city and its fortified walls during the approximate periodoftheevent.The study explores the possibility that the destruction of Jericho's walls could haveascientificexplanation based on natural phenomena. The theory of resonance is proposed, suggestingthat soundwaves generated by the human shouting might have matched the natural frequency of thewalls,weakening their structure and causing their collapse. Resonance calculations indicate that humanshouting (300 Hz) was closer to the wall's natural frequency (121.72 Hz) than the trumpets (1400Hz),implying a higher potential for resonance with the shouting.Despite these plausible explanations, thestudy emphasizes the historical and religious ambiguity surrounding the event. The biblical accountofthe conquest of Jericho has been regarded as a miraculous event, and the exact cause of thewalls'destruction remains unresolved. This event has left a profound impact on Westerncultureandreligion, with interpretations continuing to be subject to debate and contemplation.Thestudyhighlights the significance of dialogue between science and religion. Archaeology and scienceofferanobjective and data-based perspective, while religious beliefs provide spiritual and moral meaningtohistorical events. The coexistence of these approaches enriches our understanding of thepastandcultural heritage.The present work offers a multidisciplinary view that encompasses archaeology,science, and religious beliefs. Although plausible scientific explanations have been proposed, theexactnature of the destruction of Jericho's walls remains a mystery, underscoring the richness of historicaland cultural interpretations surrounding this event.

Traditionally, in the construction sector it has been common to use materials indigenous to the construction site, such as bricks, cork, wood, etc. and this has significantly reduced energy costs and environmental impact. Similarly, there has been an adjustment of building design to local climatic conditions, resulting in improved building quality and thermal comfort for occupants. Currently, the massive use of global materials such as cement, aluminum, concrete, PVC, etc., has led to a significant increase in energy and environmental costs.

In buildings, ventilation, or rather, a lack of airtightness facilitates air leaks, from the outside to the inside and vice versa, and is not controlled. Cold air enters through the enclosure, and warm air is lost to the outdoors, due to the poor hermeticity of the facades, roofs, carpentry, ducts, etc. In order to quantify the airtightness in multi-family dwellings in Madrid, 151 blower door tests have been carried out in multi-family dwellings built in different periods whose execution has been regulated by the UNE-EN 13829 standard. Through its quantification by an n50 value, the average values of 5.8 renovations per hour have been obtained in addition to detecting the main points where air infiltration occurs. The constant improvement in the transmittance of construction elements has indicated that the entry of outside air has a progressively greater relevance to the total energy consumed by the residential sector while facilitating the uncontrolled movement of air through the building envelope. This not only implies higher energy consumption but also generates a series of problems that affect the health of the occupants, such as a lack of thermal comfort, entry of pollutants and odours, noise, inadequate operation of ventilation systems, and less protection against fire.

El enfoque principal de este estudio es discutir la influencia de la longitud del proyectil en los resultados de un experimento de la barra Hopkinson de tracción (SHTB). Se han realizado simulaciones por medio de elementos finitos utilizando el software comercial ABAQUS en ensayos de tracción a altas velocidades de deformación en muestras de aleación de aluminio 7017T73 variando la longitud del proyectil. Los análisis por elementos finitos se han aplicado para simular los efectos de la variación de la longitud del proyectil en las mediciones obtenidas en las barras incidente, reflejada y transmitida. Se han obtenido diferentes velocidades de deformación, al variar la longitud del proyectil permaneciendo su velocidad constante. Los resultados de la simulación muestran que la longitud del proyectil tiene un efecto significativo en la tensión obtenida en la muestra y también en la curva de tensión-deformación. Se puede concluir que la longitud del proyectil es un factor que influye en los ensayos de tracción dinámica, ya que tiene un efecto significativo en la tensión obtenida dentro de la probeta. Las simulaciones también proporcionan información complementaria a los experimentos y una comprensión profunda del comportamiento de la probeta.

Residents of nursing homes have been significantly affected by COVID-19 in Spain. The factors that have contributed to the vulnerability of this population are very diverse. In this study, physical agents, chemical pollutants, population density and different capacities of residences were analysed to understand their influence on the number of elderly people who have died in geriatric centres in different autonomous communities (AACCs) of Spain. A statistical analysis was carried out on the variables observed. The results show that many residences with a larger number of deaths were private, with some exceptions. Physical agents and pollutants were found to be determining factors, especially for the communities of Extremadura and Castilla–La Mancha, although the large number of factors involved makes this study complicated. The compromise between air quality and energy efficiency is of great importance, especially when human health is at stake.