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Validation of Dynamic Natural Ventilation Protocols for Optimal Indoor Air Quality and Thermal Adaptive Comfort during the Winter Season in Subtropical‐Climate School Buildings
Get PDFThe need for energy-efficient buildings must be based on strong effective passive-design techniques, which coordinate indoor air quality and thermal comfort. This research describes the principles, simulation, implementation, and monitoring of two different natural cross-ventilation algorithm scenarios applied to a school-building case study affected by a subtropical climate during the winter season. These ventilation protocols, the steady and dynamic versions, can control the carbon dioxide concentration and actuate the window openings according to pre-defined window-to-wall ratios. The implementation of the monitoring process during three non-consecutive days in the winter of 2021 validates the opening strategy to maintain carbon dioxide below 800 ppm, described by the protocol Hygiene Measures Against COVID-19, and the temperature within the comfort ranges suggested by the adaptive UNE-EN 16798. The study shows that a steady opening of 2.16% window-to-wall equivalent ratio can be enough to maintain the requested comfort and carbon dioxide conditions. The use of the dynamic window ratios, from 0.23% to 2.16%, modified according to the measured carbon dioxide concentration, can partially maintain the carbon dioxide below the required limits for ASHRAE 62.1, Hygiene Measures Against COVID-19 and UNE-EN 16798 between 48.28% to 74.14% of the time. However, the carbon dioxide limit proposed by RITE, 500 ppm, is only achieved for 15.52% of the time, which demonstrates the inadequacy of the natural ventilation to fulfil the standard. Further improvements in the dynamic control of the openings in these buildings could lead to lower carbon dioxide concentrations while maintaining the thermal comfort in mild winter climates.This work has been funded by the Research Center for Technology, Energy and Sustainability (CITES) at the University of Huelva (Spain).Ingeniería Electrónica, de Sistemas Informáticos y Automátic
Magnetic analysis of slates from Courel Mountains UNESCO Global Geopark (Spain) for determining maximum temperatures of forest fires
No full textEspaña es el país más afectado por incendios forestales de Europa y su frecuencia va aumentando. Por tanto, es importante caracterizar los efectos que el aumento de temperatura genera sobre las
rocas, especialmente en contextos en los que el patrimonio geológico pueda verse afectado. Este trabajo presenta el estudio de magnetismo de rocas como una potencial técnica para conocer los efectos
producidos por el aumento de temperatura. Esta técnica permite
conocer la mineralogía, transformaciones mineralógicas asociadas
a la temperatura y tiempo, así como la temperatura máxima alcanzada durante un incendioSpain is the country in Europe most affected by forest fires and
they are increasingly frequent. Therefore, it is important characterising the effects on rocks of temperature increase, particularly in
contexts in which geological heritage could be affected. This paper
presents the study of rock magnetism as a potential technique to
know the effects of temperature increase. This technique allows
knowing mineralogy, mineralogical transformations associated with
temperature and time, as well as the maximum temperatures reached during a fir
Sustainability of Environmental Solidarity Initiatives in Colombia Within Elinor Ostrom's Organizational Design Principles
No full textColombia ha iniciado su proceso de participación
en los proyectos ambientales de la
agenda global de las Naciones Unidas para la
mitigación del cambio climático y la protección
de la biodiversidad. Por ello las organizaciones
del sector solidario han formulado proyectos
buscando alinearse con los programas
regionales y propender por el liderazgo en el
desarrollo rural a través de las iniciativas ambientales
solidarias. Entre ellas se encuentran
las organizaciones Canapro Ambiental, Cooperación
Verde y Cootregua por su participación
y acompañamiento a los proyectos ambientales
locales. De esta manera se han identificado
los elementos comunes relacionados a los
principios del diseño organizacional, los cuales
fueron planteados por Elinor Ostrom como metodología
cualitativa para la sostenibilidad basada
en la investigación exploratoria de campo.
Así fue posible corroborar la relevancia de los
principios para las iniciativas ambientales solidarias,
en el favorecimiento de los objetivos de
la sostenibilidad y la gobernanza.Colombia has begun the process of participating
in the environmental projects of the
United Nations Global Agenda for the mitigation
of climate change and the protection of
biodiversity. For this reason, organizations in
the solidarity sector have formulated projects
that seek to align themselves with regional
programs and promote leadership in rural
development through solidarity-based environmental
initiatives. Among them are the organizations
Canapro Ambiental, Cooperación
Verde and Cootregua for their participation
and accompaniment of local environmental
projects, which are the focus of this study. In
this way, common elements were identified related
to the principles of organizational design
proposed by Elinor Ostrom as a methodology
for qualitative validation of sustainability based
on exploratory field research. In this way,
the relevance of the principles for environmental
solidarity initiatives has been confirmed, in
favor of the objectives of sustainability and
governance
Study of vulnerabilities in the Dynamixel communications protocol applied to robotic platforms
No full textLa seguridad en las plataformas robóticas es una necesidad detectada por distintas instancias de alto nivel, como el Instituto Nacional de Ciberseguridad. En este contexto, el artículo presenta un estudio sobre las vulnerabilidades de un protocolo de comunicaciones utilizado en plataformas robóticas, el protocolo Dynamixel que soporta la transmisión de comandos de control utilizada por los actuadores digitales de esta marca. Dicho estudio ha revelado que el protocolo es vulnerable frente a ataques
del tipo ”hombre de en medio”. Con el fin de abordar el estudio de esta vulnerabilidad, se han implementado transmisores de
paquetes y módulos de ataque desarrollados mediante lenguaje VHDL, para su implantación en plataformas basadas en FPGA.
Seguidamente, se han puesto de manifiesto las vulnerabilidades utilizadas por el atacante para llevar a cabo tal ataque, así como posibles estrategias de defensa que pueden ser implementadas en la arquitectura de la plataforma robótica.Security in robotic platforms is a need detected by high-level entities such as the National Cybersecurity Institute. In this
context, the article presents a study on the vulnerabilities of a communication protocol used in robotic platforms, the Dynamixel
protocol, that is used by digital actuators developed by this company. This study has revealed that the protocol is vulnerable to
man-in-the-middle attacks. To this end, packet transmitters and attack modules implemented in VHDL have been developed for
implementation on FPGA-based platforms. Next, the vulnerabilities used by the attacker to carry out such an attack have been
revealed, as well as possible defense strategies that can be implemented in the robotic architecture.Ingeniería Electrónica, de Sistemas Informáticos y AutomáticaTecnologías de la Informació
Study of the 7Be(d,3He)6Li* reaction at 5 MeV/u
No full textThe measurement of the 7Be(d,3He)6Li* transfer cross section at 5 MeV/u is carried out. The population of the 2.186 MeV excited state of 6Li in this reaction channel is observed for the first time. The experimental angular distributions have been analyzed in the finite range DWBA and coupled-channel frameworks. The effect of the 7Be(d,3He)6Li reaction on both the 6Li and 7Li abundances are investigated at the relevant big-bang nucleosynthesis energies. The excitation function is calculated by TALYS and normalized to the experimental data. The S factor of the (d,3He) channel from the present work is about 50% lower than existing data at nearby energies. At big-bang energies, the S factor is about three orders of magnitude smaller than that of the () channel. The (d,3He) reaction rate is found to have a less than 0.1% effect on the 6,7Li abundances.The authors thank the ISOLDE engineers in charge, RILIS team and
Target Group at CERN for their support. D. Gupta acknowledges research
funding from the European Union’s Horizon 2020 research and
innovation programme under grant agreement no. 654002 (ENSAR2)
and ISRO, Government of India under grant no. ISRO/RES/2/378/
15−16. O. Tengblad would like to acknowledge the support by
the Spanish Funding Agency (AEI / FEDER, EU) under the project
PID2019-104390GB-I00. I. Martel would like to acknowledge the
support by the Ministry of Science, Innovation and Universities of
Spain (Grant No. PGC2018-095640-B-I00). J. Cederkall acknowledges
grants from the Swedish Research Council (VR) under contract numbers
VR-2017-00637 and VR-2017-03986 as well as grants from the
Royal Physiographical Society. J. Park would like to acknowledge
the support by Institute for Basic Science (IBS-R031-D1). A.M.M. is
supported by the I+D+i project PID2020-114687GB-I00 funded by
MCIN/AEI/10.13039/501100011033, by the grant Group FQM-160
and by project P20_01247, funded by the Consejería de Economía,
Conocimiento, Empresas y Universidad, Junta de Andalucía (Spain)
and by “ERDF A way of making Europe”.Ciencias Integrada
Reseña del libro de José del Valle Lo político del lenguaje. Travesía por el español y sus malestares Santiago de Chile, Verba Volant, 2024, 188 pp. ISBN: 978-956-08071-0-6
No full textDesorption of rare earth elements (REEs) from schwertmannite under acid mine drainage (AMD) and AMD-seawater conditions
No full textSchwertmannite as a sink for rare earth elements (REEs) in environments affected by acid mine drainage (AMD) plays a significant role in the fate of these elements. The conditions to precipitate schwertmannite (i.e., sulfate-rich water and pH between 2.5 and 3.5) are not suitable for this Fe-oxyhydroxysulfate (Fe8O8(OH)6SO4) to adsorb REEs. In estuaries where AMD-impacted rivers meet (e.g. the Odiel and the Tinto rivers in the Ría de Huelva estuary in SW Spain), AMD mixes with seawater raising the pH between 4.5 and 8, thereby enabling REE adsorption on schwertmannite at circumneutral pH. However, the estuarine tidal dynamics exposes REE-enriched schwertmannite to more acidic water, inducing REE desorption, which has yet to be studied. In the present work, batch experiments were performed to study the REE desorption from a REE-enriched schwertmannite within the pH range 4.5–7 in the presence of sulfate at room temperature. Solution-chemistry data were used to obtain the REE desorption surface constants from different surface complexation. Desorption of a Lu-enriched schwertmannite at different pH was investigated with High Energy X-Ray Diffraction (HEXD) and Extended X-ray Adsorption Fine Structure (EXAFS) to characterize the changes in the surface complexes during desorption. The results indicate that (1) REEs desorb from schwertmannite at pH < 6 and desorption is pH dependent, (2) desorption of light REEs is higher than that of heavy REEs, (3) REE sorption onto schwertmannite surface is not a totally reversible reaction, and that (4) both monodentate and bidentate surface complexes are involved in the Lu-desorption reaction. These observations indicate that (1) REE-enriched schwertmannite remains stable in the areas of the estuary nearer the sea and that (2) tidal fluctuations displace schwertmannite colloids towards areas that are more affected by AMD, inducing REE desorption from schwertmannite.This work has been funded by the CGL2017–82331-R, PID2020- 119196RB-C21, PID2020-119196RB-C22 and PID2023-153280OA-I00 projects (Spanish Ministry of Economy and Competitiveness), with contribution of FEDER funds, and by the 2021SGR00308 project funded by the Catalan Government. IDAEA-CSIC is a Severo Ochoa Center of Research Excellence (Spanish Ministry of Science and Innovation, Project CEX2018–000794-S). S. Carrero also thanks to Ramon y Cajal Program (RYC2023–04529-I). We would like to acknowledge the technical assistance of N. Moreno, J. Belles, R. Batrolí and M. Cabañas (IDAEA-CSIC). We also would like to thank the ESRF for beamtime allocation at BM30 and ID22, and their respective reviewing teams (proposals EV-438 and EV-488). We also thank the editor (Dr. Karen H. Johannesson) and three anonymous reviewers for their constructive comments that helped us to improve the quality of the manuscript.Ciencias de la Tierr
Reseña del libro de David González Ramírez, Eduardo Torres Corominas, José Julio Martín Romero, María Manuela Merino García y Juan Ramón Muñoz Sánchez (coords.), Entre historia y ficción: formas de la narrativa áurea, Madrid, Ediciones Polifemo, 2020, 292 pp.
No full textTwists About the Longitudinal Axis in Motor Practice. Bibliometric Analysis
No full textEn el ámbito deportivo, existen numerosas disciplinas
que implican rotaciones del eje longitudinal, como la
gimnasia, el salto de trampolín, la danza y el patinaje artístico. El objetivo de esta revisión bibliométrica es analizar los deportes y acciones más estudiados que implican
este tipo de rotación, así como identificar los autores, revistas y países más prolíficos y destacados, e identificar
las palabras clave y artículos más relevantes. Se siguieron las leyes tradicionales de la bibliometría. Los datos
se extrajeron de las bases de datos WoS y Scopus. Los
resultados mostraron un crecimiento exponencial con
un índice de bondad de ajuste del 78,07% entre los 150
documentos analizados. Las 68 revistas se clasificaron en
núcleo (4 revistas), zona 1 (16 revistas) y zona 2 (48 revistas). Entre los 298 autores, 24 destacaron como prolíficos
y 7 como destacados. EE.UU. fue el país más prolífico y
citado. Cabe destacar que los 21 documentos más citados se consideraron relevantes. De las 291 palabras clave, las 17 primeras son relevantes y se distribuyen en tres
grupos temáticos. El documento más antiguo, publicado
en 1971, está relacionado con el ballet, al igual que el
más citado. Los autores más relevantes son M. R. Yeadon
y M. J. Hiley, y las revistas principales están relacionadas
con la biomecánicaIn the realm of sports, there are numerous disciplines that
involve longitudinal axis rotations, such as gymnastics,
trampoline jumping, dance, and figure skating. The objective of this bibliometric review is to analyze the most
studied sports and actions that involve this type of rotation, as well as to identify the most prolific and prominent authors, journals and countries, and to identify the
most relevant keywords and articles. The traditional laws
of bibliometrics were followed. The data was extracted
from WoS and Scopus databases. The results showed exponential growth with a goodness-of-fit index of 78.07%
among the 150 documents analyzed. The 68 journals
were categorized into core (4 journals), zone 1 (16 journals), and zone 2 (48 journals). Among the 298 authors,
24 stood out as prolific and 7 as prominent authors. USA
was the most prolific and cited country. Notably, the 21
most cited documents were considered relevant. Out of
the 291 keywords, the first 17 are relevant and are distributed into three thematic groups. The oldest document,
published in 1971, is related to ballet, as is the most cited. The most relevant authors are M. R. Yeadon and M. J.
Hiley, and the core journals are related to biomechanic
Virtual and semiotics landscape of autoimmune diseases: the case of lupus
No full textEn este artículo se analiza el paisaje semiótico virtual en la imagen gráfica de las enfermedades autoinmunes, en concreto el lupus. Metodológicamente, partimos de la enfermedad
como un proceso sociosanitario y analizamos los modos actuales de visibilización discursiva de este tipo de enfermedades a través de redes sociales para conseguir resultados inmediatos sobre su percepción y aceptación en pacientes, familiares y conjunto de la sociedad.
La conclusión es que, aunque los síntomas en términos de medicina no son solo reductibles
a los signos físicos, la atenta mirada médica del territorio corporal es vital para el diagnóstico de muchas enfermedades, caso de la mariposa facial del lupusThis article analyzes the virtual semiotic landscape in the graphic image of autoimmune
diseases, specifically lupus. Methodologically, we start from the disease as a socio-sanitary process and we analyze the current ways of discursive visibility of this type of diseases
through social networks to achieve immediate results on its perception and acceptance in
patients, relatives and the entire society. The conclusion is that, although the symptoms
in terms of medicine are not only reducible to physical signs, a careful medical look at the
body’s territory is vital for the diagnosis of many diseases, such as the lupus facial butterflyEste trabajo se inscribe dentro del proyecto «Paisaje lingüístico andaluz: planificación y observación cartográfica» PLANEO (PY20-00640; Plan Andaluz de Investigación, Desarrollo e Innovación)Filologí