203 research outputs found
On the use of NASGRO software to estimate fatigue crack growth under variable amplitude loading in aluminium alloy 2024-T351
This work uses the strip yield model implemented in NASGRO software to estimate fatigue life under random loading. Simulated results were compared with experimental data previously obtained by the authors using different random loading processes in Al2024-T351. Test data under constant amplitude loading from different authors have been considered in order to characterize the material behaviour and fit the model parameters. The two different strip yield model implemented in NASGRO software were considered. The ratio of simulated to experimental fatigue lives was between 0.71 and 1.52 considering all options and between 0.87 and 1.12 with the best option.Ministerio de Economía y Competitividad DPI2012-33382Junta de Andalucía TEP-324
Perturbaciones tropicales en el Atlántico norte suroriental. Estado de la cuestión y perspectivas de futuro
This study analyzes tropical disturbances in a region usually not affected by these events, the southeastern North Atlantic. This is an extensive area between Macaronesia and the coasts of northwest Africa and the southwest of the Iberian Peninsula. In the context of climate change, a statistical analysis has been conducted of the main database of the National Hurricane Center for the Atlantic basin, as well as a bibliographical compilation, in order to analyze the temporal and spatial evolution of these phenomena. The starting hypothesis is to verify the existence of an increase in the risk of these situations in the region of study, through research that characterizes and charts these phenomena. The results indicate that, although with long periods of recurrence, some events with notable impacts had occurred before the first systematic records were kept. In addition, over the last fifty years, a much more reliable period from a scientific perspective, there has been an increase in their number, especially in recent decades. Furthermore, an approximate estimate is made of the population likely to be affected by tropical disturbances, which estimates that more than twenty million people are at risk.Se presenta un estudio sobre las perturbaciones tropicales en una región habitualmente no afectada por estos eventos, el Atlántico norte suroriental. Se trata de una extensa área entre la Macaronesia y las costas del noroeste de África y suroeste de la península ibérica. En el contexto del cambio climático se hace un análisis estadístico de la principal base de datos del National Hurricane Center para la cuenca atlántica, así como una recopilación bibliográfica, con el fin de analizar la evolución temporal y espacial de estos fenómenos. La hipótesis de partida es comprobar la existencia de un incremento en el riesgo de estas situaciones en la región de análisis, para lo que se elabora un estudio que las caracteriza y contabiliza. Los resultados señalan que, aunque con periodos de recurrencia largos, se han dado algunos eventos con destacados impactos antes del comienzo sistemático de su registro. Además, en los últimos 50 años, periodo mucho más fiable desde una perspectiva científica, se constata un aumento en su número, especialmente en las últimas décadas. Asimismo, se hace una aproximación a la población susceptible de ser afectada por las perturbaciones tropicales, la cual se estima en más de 20 millones de personas en riesgo.This research is part of the research project “MYRIAD-EU: Multi-hazard and sYstemic framework for enhancing Risk-Informed mAnagement and Decision-making in the EU”
ASSESSMENT OF STUDENTS IN THE USE OF MATLAB GUIDE TEMPLATES FOR SOLVING MATERIAL BALANCES. A TEACHING EXPERIENCE IN CHEMICAL ENGINEERING DEGREE
Domínguez-Candela, I.; Cardona, SC.; Lora-García, J.; López Pérez, MF.; Fombuena, V. (2021). ASSESSMENT OF STUDENTS IN THE USE OF MATLAB GUIDE TEMPLATES FOR SOLVING MATERIAL BALANCES. A TEACHING EXPERIENCE IN CHEMICAL ENGINEERING DEGREE. IATED Academy. 5926-5933. https://doi.org/10.21125/inted.2021.11885926593
COVID-XNet: a custom Deep Learning system to diagnose and locate COVID-19 in chest X-ray images
The COVID-19 pandemic caused by the new coronavirus SARS-CoV-2 has changed the world as we know it. An early diagnosis is crucial in order to prevent new outbreaks and control its rapid spread. Medical imaging techniques, such as X-ray or chest computed tomography, are commonly used for this purpose due to their reliability for COVID-19 diagnosis. Computer-aided diagnosis systems could play an essential role in aiding radiologists in the screening process. In this work, a novel Deep Learning-based system, called COVID-XNet, is presented for COVID-19 diagnosis in chest X-ray images. The proposed system performs a set of preprocessing algorithms to the input images for variability reduction and contrast enhancement, which are then fed to a custom Convolutional Neural Network in order to extract relevant features and perform the classification between COVID-19 and normal cases. The system is trained and validated using a 5-fold cross-validation scheme, achieving an average accuracy of 94.43% and an AUC of 0.988. The output of the system can be visualized using Class Activation Maps, highlighting the main findings for COVID-19 in X-ray images. These promising results indicate that COVID-XNet could be used as a tool to aid radiologists and contribute to the fight against COVID-19.European Regional Development Fund COFNET TEC2016-77785-PAndalusian Regional (Spain) / FEDER Project PAIDI2020Andalusian Regional /FEDER PROMETEO AT17-5410-US
HOW TO GUIDE CHEMICAL ENGINEERING STUDENTS IN THE SOLUTION OF COMPLEX ENGINEERING PROBLEMS
[EN] If we analyse some of the specific skills of Chemical Engineering degree, and it would not be very
different in other disciplines of engineering, the verbs design, analyse or simulate stand out above all.
In essence, calculating is an intrinsic activity for the engineer and, therefore, for engineering students.
How is this activity developed? When we face a real problem we translate it into mathematical language
(modelling). We solve the resulting mathematical problem to obtain the mathematical solution
(simulation). The analysis of the results allows us to extract information from the real problem. If the
interpretation of the results does not fit with the real problem studied, we must rethink the mathematical
model obtained, and so on.
Teachers often restrict the real problems that students face to simple situations so that the resulting
mathematical problem is simple and, if possible, provides an analytical solution. Why should we do this
today if we have numerical methods, a big computing power and mathematical software available to our
students? Examples of complex mathematical problems arise from analysis and design of heat
exchangers, chemical reactors, distillation columns, etc, both in steady and transitory regimes. These
mathematical problems can be classified in groups: solving algebraic equations, ordinary differential
equations or partial differential equations systems.
According to this classification, some teachers of the Chemical Engineering degree at Campus of Alcoy
are providing our students with Matlab guide templates to solve these types of mathematical problems,
regardless of the subjects in which these problems appear. This action makes it easier for students to
face real problems by reducing the mathematical difficulties associated.
This paper shows how these Matlab guide templates are and how students use them in different
subjects. It allows students to focus on the engineering aspect of the processes, leaving the difficulty of
the associated mathematical problem in a second plane. It also makes easy to modify process
parameters to quickly see the effect on the main variables of the process (what if? analysis).
Consequently, students improve their ability to analyse and interpret the results obtained and their
critical thinking skills. And, finally, they know useful computer tools that can be used both academically
and professionallyCarbonell Alcaina, C.; Cardona, SC.; Domínguez-Candela, I.; Fombuena, V.; López Pérez, MF.; Lora-García, J. (2021). HOW TO GUIDE CHEMICAL ENGINEERING STUDENTS IN THE SOLUTION OF COMPLEX ENGINEERING PROBLEMS. IATED. 9442-9450. https://doi.org/10.21125/inted.2021.1977S9442945
Synthesis of 3-amino-2-ethoxycarbonyl pyrido[1,2-a]thieno-[2,3-d]-4-pyrimidone derivatives and their antimalarial and cytotoxic activities in vitro
A series of 3-amino-2-ethoxycarbonyl pyrido[1,2-a]thieno[2,3-d]-4-pyrimidone 10-13 were prepared in order to investigate their cytotoxicity and antimalarial activities. Some of the them showed a promising activity. The detailed synthesis, spectroscopic, computational and biological data are described.Fil: Charris, Jaime. Universidad Central de Venezuela; VenezuelaFil: Domínguez, José. Universidad Central de Venezuela; VenezuelaFil: Cordero, Mary. Universidad Central de Venezuela; VenezuelaFil: Orfila, Luz. Universidad Central de Venezuela; VenezuelaFil: Riggione, Flavia. Universidad Central de Venezuela; VenezuelaFil: López, Simón E.. Universidad Simon Bolivar. Departamento de Quimica.; VenezuelaFil: Enriz, Ricardo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Suviere, Fernando. Universidad Nacional de San Luis. Facultad de Ciencias Físico- Matemáticas y Naturales; Argentin
Acute effects of a single tennis match on passive shoulder rotation range of motion, isometric strength and serve speed in professional tennis players
Shoulder pain has been associated with glenohumeral internal rotation deficit (GIRD) and a
reduction in external rotation (ER) strength; however, in tennis players, there is scarce evi-
dence regarding the impact of a single match on shoulder range of motion (ROM), strength
and serve speed. The aim of this study was to determine the acute effect of a single tennis
match on shoulder rotation ROM, isometric strength and serve speed. Twenty-six profes-
sional tennis players participated in the study (20.4±4.4 years; 10.5±3.2 years tennis exper-
tise; 20.5±5.4 h/week training). Passive shoulder external (ER-ROM) and internal rotation
ROM (IR-ROM), ER and IR isometric strength were measured before and after a single ten-
nis match (80.3±21.3 min) in both shoulder´s. Moreover, the total arc of motion (TAM) and
ER/IR strength ratio were calculated. Video analysis was used to assess the number of
serves and groundstrokes, while a radar gun was utilized to measure maximal ball speed. In
the dominant shoulder, compared to pre-match levels, IR-ROM was significantly reduced
(-1.3%; p = 0.042), while ER-ROM (5.3%; p = 0.037) and TAM (3.1%; p = 0.050) were signif-
icantly increased. In the non-dominant shoulder, ER-ROM (3.7%; p = 0.006) was increased.
Furthermore, in the dominant shoulder, the isometric ER strength was significantly reduced
after the match (-4.8%; p = 0.012), whereas serve speed was not significantly reduced after
match (-1.16%; p = 0.197). A single tennis match leads to significant reductions in shoulder
ROM (e.g., IR of the dominant shoulder) and isometric strength (e.g., ER of the dominant
shoulder). This study reveals the importance of recovery strategies prescription aiming at
minimize post-match alteration in the shoulders.SIThe authors would like to express their gratitude to the tennis players for their participation.The authors received no specific funding for this work
Can we predict psychostimulant use in youths? A study with structural equation modeling analysis
Conocer qué factores predicen el consumo de psicoestimulantes en jóvenes es importante para el diseño de programas preventivos y para identificar a los jóvenes que tienen una mayor probabilidad de consumir y así evitar que aparezcan los problemas derivados de dicho consumo. El objetivo de este estudio fue analizar la relación entre la disponibilidad percibida, la percepción de riesgo, los rasgos de personalidad, los patrones de personalidad antisocial y el consumo de otras sustancias en la predicción del consumo de psicoestimulantes. La muestra estuvo formada por 1.177 jóvenes (584 varones y 593 mujeres) de entre 14 y 25 años en España, reclutados aleatoriamente, estratificados por consumo-no consumo de
psicoestimulantes (cocaína o éxtasis) alguna vez en la vida. El path que mejor predijo el consumo de psicoestimulantes fue: rasgos de personalidad-patrones de personalidad antisocial- consumo de psicoestimulantes. El siguiente path fue: rasgos de personalidad- patrones de personalidad antisocial-consumo de psicoestimulantes. La percepción de riesgo y la disponibilidad percibida fueron significativas en la predicción pero aportaron una contribución menor. Los resultados de este estudio sugieren que el modelo evaluado es adecuado para la predicción del consumo de psicoestimulantes en jóvenes. Este modelo puede ser de utilidad para desarrollar estrategias preventivas y para identificar a aquellos jóvenes con riesgo de tener problemas relacionados con el consumo de drogasKnowing which factors predict the use of psychostimulant drugs among youths is important for designing preventive programs and the identification of youths with the highest probability of use, to avoid some of the problems that can be derived from it. The purpose of this study is to examine the relationship between perceived availability, risk perception, personality traits, antisocial personality patterns, and use of other substances in the prediction of psychostimulant use. The sample was composed by 1,177 youths (584 males and 593 females) aged 14 to 25 in Spain, recruited randomly, stratified by lifetime use- non use of psychostimulants (cocaine or ecstasy). The path which best predicts psychostimulant use is: Personality traits-legal substance use-cannabis use-psychostimulant use. The next path is: Personality traits-antisocial personality patterns-psychostimulant use. Risk perception and perceived availability were significant in the prediction, but made a smaller
contribution. The results of this study suggest that the model evaluated can predict psychostimulant use in youths. This model can be seen as a useful tool for developing preventive strategies and for identifying those youths that are at risk for problems related to drug useThis research was supported by Xunta de Galicia, Servicio Galego de Saúde (SERGAS) by a cooperation agreement between Xunta de Galicia-SERGAS and University of Santiago de Compostela, SpainS
Project-Based Learning as a Coordination Methodology between Subjects in a Chemical Engineering Degree
[EN] An important issue in any academic degree is to develop a high level of vertical/horizontal coordination between the different subjects taught along the four courses. This activity takes into account the coordination of the contents and methodologies that the teachers teach and the students acquire, the timing when the students learn them and the homework/exams that they do. As a result, both teachers and students gain an overall view of the degree and the teaching-learning process improves.
According to this idea, the teachers of the Chemical Engineering degree at Campus of Alcoy are participating in an Educational Innovation and Improvement Project (EIIP) for applying the project-based learning methodology to the design of an adsorption system for the elimination of dyes in wastewater from the textile industry. This work is scheduled along the four courses and is distributed between some of the basic or specialized subjects that the students attend. The adsorption column design is partially solved in each subject and the results obtained in one subject are used in the following. As a result, the project is completed sequentially throughout the degree applying a methodology based on teamwork.
This paper shows some of the activities proposed in different subjects, their timing and assessments during four courses. These activities include laboratory work for obtaining adsorption equilibrium and adsorption kinetics experimental data together with column dynamic performance. Other activities belong to the modelling and simulation domain for establishing the mathematical equations corresponding to the different phenomena linked to adsorption. Also there are activities focused on experimental data treatment for estimating the parameters characterizing the adsorption isotherms or mass transfer coefficients. Finally, other activities are devoted to the column design and control, cost estimation, and oral/writing communication of the work done by the students.This article has been supported by Universitat Politècnica de València, particularly by the Vice-rectorate
for Digital Resources and Documentation (Vicerrectorado de Recursos Digitales y Documentación) and
Vice-Rectorate for Studies, Quality and Accreditation (Vicerrectorado de Estudios, Calidad y
Acreditación) under the Call for Learning + Teaching (Convocatoria A+D2019: Aprendizaje + Docencia.
Proyectos de Innovación y Mejora Educativa) and Project Code: A157. The authors would like to
acknowledge the support of the Institute of Educational Sciences (Instituto de Ciencias de la Educación),
the Evaluation and Monitoring Commission for Educational Innovation and Improvement Projects
(Comisión de Evaluación y Seguimiento de Proyectos de Innovación y Mejora Educativa (CESPIME)
and Escuela Politécnica Superior de Alcoy.Carbonell Alcaina, C.; Cardona, SC.; Domínguez-Candela, I.; Fombuena, V.; López Pérez, MF.; Lora-García, J.; Sanchis, R. (2021). Project-Based Learning as a Coordination Methodology between Subjects in a Chemical
Engineering Degree. INTED proceedings (Online). 5965-5974. https://doi.org/10.21125/inted.2021.1193S5965597
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