Book review "CALL Research Perspectives"

[EN] Edited by Joy L. Egbert and Gina Mikel Petrie, CALL Research Perspectives Series: ESL & Applied LinguisticsProfessional Series. Series Editor: Eli Hinkel Oxford: Routledge, 2005, 216 pp. ISBN: 0-8508-5135-2Navarro Laboulais, CT. (2011). Book review "CALL Research Perspectives". The EuroCALL Review. 19(0):87-88. https://doi.org/10.4995/eurocall.2011.16276878819

Influence of hydrogen peroxide in the tribocorrosion behaviour of a CoCrMo biomedical alloy

This paper studies the influence of hydrogen peroxide (H2O2) in simulated body fluids on the wear and corrosion behaviour of a CoCrMo biomedical alloy. CoCrMo are passive materials commonly used in prosthesis and implants because of its high corrosion resistance and mechanical properties. Hydrogen peroxide is produced by bacteria and leukocytes as a consequence of an inflammatory reaction which may modify the tribo-electrochemical response of metals implanted in the human body. Indeed, the oxidizing environment generated by the presence of the peroxide increases the metal dissolution rate. Electrochemical and tribocorrosion tests were carried out in a PBS solution with different addition of H2O2 (0.5, 2, 4 and 12%).The authors acknowledge Generalitat Valencia for the Gerónimo Forteza financial support and to the Electron Microscopy Service of the UPV for the SEM images

Diseño de un plan de comunicación turística que muestre el patrimonio cultural matrilineal del pueblo Bribri (Talamanca, Costa Rica)

[EN] This research develops a tourism communication plan for the indigenous Bribri community. The main objectives of the plan are to attract quality tourism by showcasing the intangible cultural heritage of the Bribi and so help preserve their culture. We use an analytical-descriptive methodology based on an analysis of the environment and a definition of actions through participatory processes with the community. These processes are oriented towards the empowerment of indigenous women. The Bribri live in the canton of Talamanca(Costa Rica). The Bribi and other ethnic groups in the area can be distinguished from neighbouring communities because they have a matrilineal social structure, and their economies are based on farming ¿ to which has been added an incipient tourism. To enhance the durability of their cultural heritage, various actions are being implemented by the Bribri in collaboration with the Universitat Politècnica de València (UPV) and the Instituto Tecnológico de Costa Rica (TEC). These actions include the development of this communications plan ¿ which aims to preserve the imprint of Bribri culture and develop a method that can be used by other indigenous communities with similar characteristics.[ES] Esta investigación desarrolla un plan de comunicación turística para la comunidad indígena Bribri. Los principales objetivos del plan son atraer turismo de calidad mostrando el patrimonio cultural inmaterial de los Bribi y ayudar así a preservar su cultura. Se utiliza una metodología analítico-descriptiva basada en el análisis del entorno y la definición de acciones a través de procesos participativos con la comunidad. Estos procesos están orientados al empoderamiento de las mujeres indígenas. Los Bribri viven en el cantón de Talamanca (Costa Rica). Los Bribi y otras etnias de la zona se distinguen de las comunidades vecinas porque presentan una estructura social matrilineal. Su economía se basa en la agricultura, a lo que se ha sumado un incipiente turismo. Para hacer perdurar su patrimonio cultural, los Bribri están implementando diversas acciones en colaboración con la Universitat Politècnica de València (UPV) y el Instituto Tecnológico de Costa Rica (TEC). Estas acciones incluyen el desarrollo de este plan de comunicación, que tiene como objetivo preservar la impronta de la cultura Bribri y desarrollar un método que pueda ser utilizado por otras comunidades indígenas con características similares.Alonso-López, N.; Morant González, M.; Navarro Laboulais, CT. (2021). Design of a tourist communication plan that shows the matrilineal cultural heritage of the Bribri people (Talamanca, Costa Rica). Trama: Revista de Ciencias Sociales y Humanidades. 10(2):43-66. https://doi.org/10.18845/tramarcsh.v10i2.6303436610

Re-entry survival analysis and ground risk assessment of space debris considering by-products generation

[EN] Space debris that re-enter the Earth's atmosphere can be partially or fully ablated along the trajectory path after hitting the atmosphere layers, once these become denser (approximately below 82 km). This paper combines reentry survival analysis to by-product generation analyses according to specific trajectory analysis and different levels of modelling within the re-entry simulation tool. Particular attention is made on metallic alloy decomposition and metallic oxides formation from the debris' materials ablation. Generic alloys present within satellite constructions are considered. The flow field in the induced shock layer is considered to be in non-equilibrium and the trajectory tool is based on a 3DOF object-oriented approach. The by-product analyses give important information on emitted species in the atmosphere at different altitudes, and the risk of substances reaching the ground is evaluated as a function of the initial break-up altitude. The non-equilibrium atmospheric chemistry within the shock layer has a significant impact for the re-entry analysis.This work was supported by the Swiss Government Excellence Scholarship (ESKAS No. 2019.0535) awarded by Federal Commission for Scholarships (FCS). The collaboration with UPV was partially financed as part of an activity performed with TAS-I in the context of an ESA subcontract ARA, under ITT-A0/1-8558/16/NL/KML.Park, S.; Navarro-Laboulais, J.; Leyland, P.; Mischler, S. (2021). Re-entry survival analysis and ground risk assessment of space debris considering by-products generation. Acta Astronautica. 179:604-618. https://doi.org/10.1016/j.actaastro.2020.09.03460461817

Dynamic optimization of a gas-liquid reactor

The final publication is available at Springer via http://dx.doi.org/10.1007/s10910-011-9941-1A dynamic gas-liquid transfer model without chemical reaction based on unsteady film theory is considered. In this case, the mathematical model presented for gas-liquid mass-transfer processes is based on mass balances of the transferred substance in both phases. The identificability property of this model is studied in order to confirm the possible identifiable parameters of the model from a given set of experimental data. For that, a different modeled of the system is given. A procedure for the identification is proposed. On the other hand, the aim of this work is to solve the quadratic optimal control problem, using an explicit representation of the model. The problem includes some results on controllability, observability and stability criteria and the relation between these properties and the parameters of the model. Using the optimal control problem we study the stability of the system and show how the choice of the weighting matrices can improve the behavior of the system but with an increase of the energy control cost. © 2011 Springer Science+Business Media, LLC.This work has been partially supported by PAID-05-10-003-295 and by MTM2010-18228.Cantó Colomina, B.; Cardona Navarrete, SC.; Coll, C.; Navarro-Laboulais, J.; Sánchez, E. (2012). Dynamic optimization of a gas-liquid reactor. Journal of Mathematical Chemistry. 50(2):381-393. https://doi.org/10.1007/s10910-011-9941-1S381393502Bayón L., Grau J.M., Ruiz M.M., Suárez P.M.: Initial guess of the solution of dynamic optimization of chemical processes. J. Math. Chem. Model. 48, 28–37 (2010)Ben-Zvi A., McLellan P.J., McAuley K.B.: Ind. Eng. Chem. Res. 42, 6607–6618 (2003)Cantó B., Coll C., Sánchez E.: Structural identifiability of a model of dialysis. Math. Comp. Model. 50, 733–737 (2009)Cantó B., Coll C., Sánchez E.: Identifiability of a class of discretized linear partial differential algebraic equations. Math. Probl. Eng. 2011, 1–12 (2011)Craciun G., Pantea C.: Identifiability of chemical reaction networks. J. Math. Chem. 44, 244–259 (2008)Dai L.: Descriptor Control Systems. Springer, New York (1989)Deckwer W.D.: Bubble Column Reactors. Wiley, Chichester (1992)Kantarci N., Borak F., Ulgen K.O.: Bubble column reactors. Proc. Biochem. 40(7), 2263–2283 (2005)Kawakernaak H., Sivan R.: Linear Optimal Control Systems. Wiley-Interscience, New York (1972)Kuo B.C.: Automatic Control Systems, 6th edn. Prentice-Hall, Englewood Cliffs (1991)Navarro-Laboulais J., Cardona S.C., Torregrosa J.I., Abad A., López F.: Practical identifiability analysis in dynamic gas-liquid reactors. Optimal experimental design for mass-transfer parameters determination. Comp. Chem. Eng. 32, 2382–2394 (2008)Navarro-Laboulais J., López F., Torregrosa J.I., Cardona S.C., Abad A.: Transient response, model structure and systematic errors in hybrid respirometers: structural identifiabilit analysis based on OUR and DO measurements. J. Math. Chem. 44(4), 969–990 (2007)Patel R., Munro N.: Multivariable Systen. Theory and Design. Pergamon Press, New York (1982)Sondergeld K.: A generalization of the Routh–Hurwitz stability criteria and a application to a problem in robust controller design. IEEE Trans. Automat. Contr. AC-28(10), 965–970 (1983

Automatizar los exámenes del Diploma de Español como Lengua Extranjera (DELE) ¿utopía o realidad?

Este artículo trata de mostrar las dificultades y beneficios, tanto desde la perspectiva institucional como desde la del usuario, de automatizar el Diploma de Español como Lengua Extranjera (DELE). El artículo trata sobre cuestiones lingüísticas e informáticas tales como el diseño web, las realidades del uso de la lengua y, por encima de todo, muestra la necesidad de la implementación de dicho proyecto. Asimismo, muestra que si el examen de DELE se pusiera en funcionamiento, debería satisfacer tres áreas: diseño, cuestiones de la lengua y la mejora y adecuación tecnológica. En este sentido, la puesta en funcionamiento de un examen asistido por ordenador puede ser vista como una herramienta beneficiosa que permite evaluar las cuatro destrezas tradicionales más el uso de la lengua de manera más eficiente que el sistema actual de papel y lápi

Wear model for describing the time dependence of the material degradation mechanisms of the AISI 316L in a NaCl solution

[EN] The tribo-electrochemical behavior of AISI 316L has been investigated under tribocorrosion conditions in a 3% NaCl solution and the material damage evolution with time has been analyzed. A numerical contact model based on a Boundary Element Method (BEM) has been developed in order to determine the contact pressure distribution and to quantify the worn material as a function of time. The time dependence of the tribological behavior of the material has been described. At the initial state, the high contact pressures generate a material flow causing an increase in the worn area. After around 300 cycles, the Archard wear model linearly describes the wear evolution with time. The proposed model describes the evolution with time of the wear profiles of the tested material and takes into account the plastic behavior of the material during the first cycles.This work has been funded by the Spanish Ministry of Economy and Competitiveness under the Ref. MAT2014-53764-C3-3-R and the Generalitat Valenciana under the PROMETEO program Ref. 2016/040.Dalmau-Borrás, A.; Roda Buch, A.; Rovira, A.; Navarro-Laboulais, J.; Igual Muñoz, AN. (2018). Wear model for describing the time dependence of the material degradation mechanisms of the AISI 316L in a NaCl solution. Wear. 394-395:166-175. https://doi.org/10.1016/j.wear.2017.10.015S166175394-39

Chemo-mechanical effects on the tribocorrosion behavior of titanium/ceramic dental implant pairs in artificial saliva

[EN] In this paper, the degradation mechanisms of the ceramic and the metal in Titanium/Zirconia pairs for biomedical applications were analyzed. To do that, an experimental set-up with well-controlled mechanical and chemical conditions was used based on a unidirectional ball-on-disk tribometer coupled to a potentiostat. Tribocorrosion tests were carried out in artificial saliva at different applied potentials, this is, different chemical conditions of the surface. Wear damage of the titanium/zirconia pair was influenced by the properties and the behavior of wear debris in the contact. Under passive conditions metallic and oxidized titanium particles (formed by the cyclic removal of the passive film and subsequent repassivation) were smeared and mechanically mixed within the contact forming compacted wear debris through which the loading was carried out. Properties and amount of oxidized titanium lead to low wear at low passive conditions (OCP) and higher wear at high passive conditions. Zirconia did not suffer any damage under all the studied conditions and oxidized titanium was transferred to the ball at anodic applied potentials.Authors would like to acknowledge the Generalitat Valenciana for the financial support under the PROMETEO/2016/040 and GV/2017/042 projects. A. Dalmau acknowledges the Generalitat Valenciana for her contract (APOSTD/2017/051).Dalmau-Borrás, A.; Roda Buch, A.; Rovira, A.; Navarro-Laboulais, J.; Igual Muñoz, AN. (2019). Chemo-mechanical effects on the tribocorrosion behavior of titanium/ceramic dental implant pairs in artificial saliva. Wear. 426-427:162-170. https://doi.org/10.1016/j.wear.2018.12.052162170426-42

Análisis estructural de los problemas orientado al aprendizaje de Operaciones de Separación

[EN] The subject Unit Operations of the Bachelor degree in Chemical Engineering is focused on learning the common operations used in chemical processes. After our experience, most of the students perceive that the subject is made up of independent learning units which requires the study of a great amount of theoretical concepts involving several unconnected calculations for each one, so they think the subject is tedious and complex. The reason is that they are not aware about the similarities among the unit operations. Besides, the procedures required to solve full exercises are hard for them and they misunderstood the reasoning process. A deep analysis of the exercises used to learning the unit operation calculations was carried out. Besides, the main features of mathematical software used (Mathcad) were considered. The aim is to do the reasoning process more visual, to facilitate the awareness of the transversality of the several unit operations and to reduce the time spent on the problem-solving. The result has been the restructuration of the exercise by means of “calculation areas” and the implementation of “function libraries”, which has improved the learning outcomes[ES] La asignatura Operaciones de Separación del Grado de Ingeniería Química se centra en el aprendizaje de las operaciones de mayor aplicación en procesos de ingeniería química. La falta de conciencia de las similitudes entre las distintas operaciones hace que una gran parte de los alumnos tenga la visión de que la asignatura está formada por unidades inconexas que requieren el estudio de muchos conceptos teóricos con cálculos diferenciados para todos ellos, de manera que les parece poco atractiva, compleja y voluminosa. La resolución de un problema completo les resulta, en general, larga y tienden a perderse en el proceso de razonamiento. Estas dificultades se han hecho más evidentes en los estudios de Grado, respecto a la misma asignatura de la anterior titulación de Ingeniero Químico. Por ello, se ha realizado un profundo análisis de los problemas utilizados para aprender los cálculos de cada operación, así como de las características del software utilizado en su resolución (Mathcad). Todo ello con el objetivo de hacer facilitar el proceso de razonamiento y la conciencia de transversalidad entre las distintas operaciones y de disminuir el tiempo requerido. Como resultado se han restructurado los problemas con el uso de “zonas de cálculo” y la creación de “librerías de funciones”, lo que ha supuesto una mejora en el aprendizaje.Los miembros del grupo ASEI agradecen al Vicerrectorado de Estudios y Convergencia Europea y al Instituto de Ciencias de Educación de la Universitat Politècnica de València la concesión del PIME A26/14 “Desarrollo de estrategias para la mejora del aprendizaje y evaluación de los problemas de Operaciones de Separación”Santafé Moros, MA.; Gozálvez Zafrilla, JM.; Navarro Laboulais, JJ. (2015). Análisis estructural de los problemas orientado al aprendizaje de Operaciones de Separación. En In-Red 2015 - CONGRESO NACIONAL DE INNOVACIÓN EDUCATIVA Y DE DOCENCIA EN RED. Editorial Universitat Politècnica de València. https://doi.org/10.4995/INRED2015.2015.1632OC

Adaptación de metodologías docentes para la enseñanza de problemas en aula informática con el objetivo de formar en competencias de nivel de Máster

[EN] This work analyzes the adaptation and development of teaching methodologies for problem solving strategies in the subject “Advanced Unit Operations” of the Master in Chemical Engineering for developing transversal key competences. As starting point, it has been used the teaching methodology developed in the former curriculum adapted to the new one. The adaptation was performed through two different ways. On the one hand, problems of open response supported by mathematical software were included. On the other hand, new computational resources, like simulation and design software, were introduced to make the student easier the exploration of different process alternatives. The inclusion of these problems implied changes in the evaluation procedure. The effects of the methodological changes performed are shown in relation with the acquired competences by the students and with the necessary changes in the evaluation procedure. A survey among the students shows a positive opinion in relation to the methodological adaptations performed.[ES] En este trabajo se analiza la adaptación y desarrollo de metodologías docentes para el aprendizaje de la resolución de problemas en la asignatura del Máster de Ingeniería Química “Operaciones de Separación Avanzadas” con el objetivo de desarrollar competencias transversales. Como punto de partida se considera la metodología que desarrollamos para las clases de problemas del plan de estudios previo. La adaptación se realizó a través de dos vías diferentes. Por una parte, se realizaron cambios en el tipo de problemas propuestos y en la forma de evaluación, trabajándose con problemas de tipo más abierto apoyados por software matemático. Por otra parte, se introdujeron nuevos recursos como programas de simulación y de diseño de procesos con el fin de facilitar al alumno la posibilidad de explorar alternativas. Los efectos de estos cambios se indican en este artículo relacionándolos con las competencias que favorecen y con los cambios en el sistema de evaluación necesarios. El análisis de los resultados de una encuesta mostró una opinión favorable hacia las adaptaciones metodológicas realizadas.Los autores agradecen al Vicerrectorado de Estudios y Convergencia Europea y al Instituto de Ciencias de Educación de la Universitat Politècnica de València la concesión del Proyecto de Innovación y Mejora Educativa PIME A26/14 “Desarrollo de estrategias para la mejora del aprendizaje y evaluación de los problemas de Operaciones de Separación”Gozálvez Zafrilla, JM.; Santafé Moros, MA.; Navarro Laboulais, JJ. (2015). Adaptación de metodologías docentes para la enseñanza de problemas en aula informática con el objetivo de formar en competencias de nivel de Máster. En In-Red 2015 - CONGRESO NACIONAL DE INNOVACIÓN EDUCATIVA Y DE DOCENCIA EN RED. Editorial Universitat Politècnica de València. https://doi.org/10.4995/INRED2015.2015.163