Diseño y cálculo de condensadores evaporativos

En el presente trabajo se lleva a cabo un diseño y análisis general de condensadores evaporativos, utilizando la aplicación informática de programación Matlab. Para llevar a cabo este diseño se ha desarrollado un método de cálculo basado en los balances de masa y energía en el interior de dicho condensador, obteniendo la evolución de las variables que gobiernan el comportamiento del mismo. Mediante los datos de entrada del condensador, tales como las condiciones ambientales externas, la potencia que debe evacuar el condensador, junto con el tipo de refrigerante y sus condiciones de condensación y la configuración geométrica del mismo, se va a obtener como resultado la evolución de estos datos en el interior del condensador, así como los datos de salida del mismo. Para desarrollar este método de cálculo se hace imprescindible el uso de aplicaciones informáticas, ya que es necesario resolver varias ecuaciones diferenciales mediante méto-dos iterativos. En este caso se ha optado por utilizar el lenguaje de programación Matlab, mediante la herramienta de interfaz gráfica GUI. Se han implementado los cálculos en este lenguaje de programación, así como las distintas alternativas de diseño que se van a exponer durante el trabajo. Además, se van a comparar los resultados obtenidos en el condensador evaporativo con los resultados en otro tipo de condensadores que existen en el mercado, para las mis-mas condiciones de operación. Finalmente, se comentarán las conclusiones extraídas por el autor durante la realización del presente trabajo, haciendo especial hincapié en el desarrollo de la aplicación con Matlab.At this paper a general design and analysis of evaporative condensers is made, using the computer application Matlab. To carry out this design, a calculation method based on mass and energy balances in the condenser has been developed, obtaining the evolution of variables that govern the behavior of the condenser. Through condenser input data, such as air conditions, the removed heat by the condenser, its geometric and the type of refrigerant and its condensation conditions; the evolution and output of these data have been obtained as a result. To develop this method, the use of computer applications is essential, because it is necessary to solve several differential equations, using iterative methods. In this case, the Matlab programming language has been chosen, by using of GUI tool. Required calculations for this method have been implemented in this programming language, as well as the design alternatives presented at this paper. In addition, results obtained for the same operating conditions for the evaporative condenser and the other types of condensers present in the industry, have been compared and analyzed. Finally, conclusions obtained by the author during the course of this project, with par-ticular emphasis on the development of implementation with Matlab, have been commented.Ingeniería Mecánic

Osteochemonecrosis of the jaws due to bisphosphonate treatments : update

Bisphosphonates (BP),were initially used in industry and later as a drug due to their great affinity to osseous tissue, because of their powerful antiresorptive effect as a treatment in various osteopathies, such as osteoporosis, Paget disease or hypercalcemia associated with some malignant tumors, as myeloma or breast cancer. They are administered orally or intravenously, and although well tolerated, the most frequent side effects are gastrointestinal, in addition to osteonecrosis when they are administered via endovenous. The aim of this work has been to evaluate the existing publications in accredited scientific literature on biphosphonates and their action mechanism and the relationship with the appearance of osteonecrosis of the jaws. Although the mechanism by which osteonecrosis of the jaws develops is not known exactly, there seems to be influence by osteoclast inhibiton, antiangiogenic action, an inhibitory effect on the cellular cycle by the keratinocytes, as well as, reinforcement of the chemiotoxic action in oncological patients treated with other drugs. Clinically, it ranges from a non-specificity of symptoms to lesions such as osteomyelitis with necrosis and osseous sequesters that may be accompanied by fetor ex oris, with the appearance of many Actinomyces contaminated lesions. As for published antecedents on osteonecrosis due to bisphosphonate treatment found until 2006: 46.5% had a previous diagnosis of multiple myeloma; 38.8% were patients with metastatic breast cancer; 6.2% patients of metastatic prostate cancer; 4.1% suffered from osteoporosis; 3.5% from other metastatic diseases and 0.8% had Paget disease. The drugs that seem to have the highest incidence of osteochemionecrosis are: zoledronate, pamidronate, alendronate, risendronate and ibandronate, from the greatest to the least. Additionally, the risk of osteonecrosis being produced is accumulative and may reach 21% in the third year of intravenous bisphosphonate use

Temperature Measurement in PV Facilities on a Per-Panel Scale

This work is a contribution of the DPI2010-17123 Project supported by the Spanish Ministry of Education and Science and the TEP-6124 Project supported by the Regional Government of Andalusia (Spain). Both projects are also supported by the European Union Regional Development Fund.This paper presents the design, construction and testing of an instrumentation system for temperature measurement in PV facilities on a per-panel scale (i.e., one or more temperature measurements per panel). Its main characteristics are: precision, ease of connection, immunity to noise, remote operation, easy scaling; and all of this at a very low cost. The paper discusses the advantages of temperature measurements in PV facilities on a per-panel scale. The paper presents the whole development to implementation of a real system that is being tested in an actual facility. This has enabled the authors to provide the readers with practical guidelines, which would be very difficult to achieve if the developments were implemented by just simulation or in a theoretical way. The instrumentation system is fully developed, from the temperature sensing to its presentation in a virtual instrument. The developed instrumentation system is able to work both locally and remotely connected to both wired and wireless network

Molecular weight dependence and stereoselective chain cleavage during the early stages of the isotactic polypropylene pyrolysis

The comparative study on the pyrolysis of two Polypropylene samples, with a similar high isotactic character but quite distinct molecular weights, reveals a significant difference in their thermal performances. The detailed qualitative analysis of the parameters, which are expected to govern the thermal degradation, leads to reasonably assume a main role of the molecular weight in their relative early stabilities. Furthermore, the correlation found between the sharp initial build-up of the Eact and the selective cleavage of isotactic stereosequences in both samples, suggests the relevance of the stereoregular length into the energy required for chain scissionThe authors acknowledge the financial support of project MAT2016-79869-C2-1-P (AEI/FEDER, UE), as well as the kindly assistance of Repsol for the supply of samples.Peer reviewe

Relevance of Skills in Total Quality Management in Engineering Studies as a Tool for Performing Their Jobs

[EN] The Spanish higher education system needs to adapt to the requirements of the European Higher Education Area and to this end, it is necessary for higher education institutions to improve the quality of university education, leading to an increase in competency-based learning activities aimed at developing the skills of graduates. Since university graduates face a large number of requirements when entering the labour market, they need to develop and constantly update the appropriate skills to carry out their work properly. This paper aims to address two fundamental questions. First, do engineering graduates need acquired skills in Total Quality Management (TQM) to perform their jobs successfully? Secondly, which job profile requires the highest level of Total Quality Management training and knowledge? We carried out different multivariate statistical analyses using a sample of engineering graduates who had been in the labour market for two years. The results show that knowledge of this type of management philosophy is necessary for adequate job performance. The job profile requiring the highest level of skills in TQM is described.Martínez-Gómez, M.; Jabaloyes Vivas, JM.; Carrión García, A. (2020). Relevance of Skills in Total Quality Management in Engineering Studies as a Tool for Performing Their Jobs. Sustainability. 12(5):1-15. https://doi.org/10.3390/su12052065S115125Kanji, G. K., Malek, A., & Tambi, B. A. (1999). Total quality management in UK higher education institutions. Total Quality Management, 10(1), 129-153. doi:10.1080/0954412998126Heijke, H., Meng, C., & Ramaekers, G. (2003). An investigation into the role of human capital competences and their pay‐off. International Journal of Manpower, 24(7), 750-773. doi:10.1108/01437720310502113Jaca, C., & Psomas, E. (2015). Total quality management practices and performance outcomes in Spanish service companies. Total Quality Management & Business Excellence, 26(9-10), 958-970. doi:10.1080/14783363.2015.1068588Chen, R., Lee, Y.-D., & Wang, C.-H. (2018). Total quality management and sustainable competitive advantage: serial mediation of transformational leadership and executive ability. Total Quality Management & Business Excellence, 31(5-6), 451-468. doi:10.1080/14783363.2018.1476132Weil, S. (1999). Re-creating universities for ‘beyond the stable state’: from ‘Dearingesque’ systematic control to post-Dearing systemic learning and inquiry. Systems Research and Behavioral Science, 16(2), 171-190. doi:10.1002/(sici)1099-1743(199903/04)16:23.0.co;2-aSleezer, C. M., Gularte, M. A., Waldner, L., & Cook, J. (2008). Business and Higher Education Partner to Develop a High-Skilled Workforce: A Case Study. Performance Improvement Quarterly, 17(2), 65-81. doi:10.1111/j.1937-8327.2004.tb00308.xPossa, G. (2006). Europe’s Universities in Response to Europe’s Challenges. Higher Education in Europe, 31(4), 355-357. doi:10.1080/03797720701302907Andrews, J., & Higson, H. (2008). Graduate Employability, ‘Soft Skills’ Versus ‘Hard’ Business Knowledge: A European Study. Higher Education in Europe, 33(4), 411-422. doi:10.1080/03797720802522627Yusof, S. M., & Aspinwall, E. (2000). Total quality management implementation frameworks: Comparison and review. Total Quality Management, 11(3), 281-294. doi:10.1080/0954412006801Dean, J. W., & Bowen, D. E. (1994). MANAGEMENT THEORY AND TOTAL QUALITY: IMPROVING RESEARCH AND PRACTICE THROUGH THEORY DEVELOPMENT. Academy of Management Review, 19(3), 392-418. doi:10.5465/amr.1994.9412271803Hellsten, U., & Klefsjö, B. (2000). TQM as a management system consisting of values, techniques and tools. The TQM Magazine, 12(4), 238-244. doi:10.1108/09544780010325822Curry, A., & Kadasah, N. (2002). Focusing on key elements of TQM – evaluation for sustainability. The TQM Magazine, 14(4), 207-216. doi:10.1108/09544780210429816Hackman, J. R., & Wageman, R. (1995). Total Quality Management: Empirical, Conceptual, and Practical Issues. Administrative Science Quarterly, 40(2), 309. doi:10.2307/2393640Singh, P. J., & Smith, A. J. R. (2004). Relationship between TQM and innovation: an empirical study. Journal of Manufacturing Technology Management, 15(5), 394-401. doi:10.1108/17410380410540381Asif, M., Searcy, C., Garvare, R., & Ahmad, N. (2011). Including sustainability in business excellence models. Total Quality Management & Business Excellence, 22(7), 773-786. doi:10.1080/14783363.2011.585784Rocha-Lona, L., Garza-Reyes, J. A., Lim, M. K., & Kumar, V. (2015). Corporate Sustainability and Business Excellence. 2015 International Conference on Industrial Engineering and Operations Management (IEOM). doi:10.1109/ieom.2015.7093844Zink, K. J. (2007). From total quality management to corporate sustainability based on a stakeholder management. Journal of Management History, 13(4), 394-401. doi:10.1108/17511340710819615Lagrosen, Y., & Lagrosen, S. (2019). Creating a culture for sustainability and quality – a lean-inspired way of working. Total Quality Management & Business Excellence, 1-15. doi:10.1080/14783363.2019.1575199Motwani, J. (2001). Critical factors and performance measures of TQM. The TQM Magazine, 13(4), 292-300. doi:10.1108/13683040010362300Rahman, S. (2001). A comparative study of TQM practice and organisational performance of SMEs with and without ISO 9000 certification. International Journal of Quality & Reliability Management, 18(1), 35-49. doi:10.1108/02656710110364486Petroni, A. (2002). Critical factors of MRP implementation in small and medium‐sized firms. International Journal of Operations & Production Management, 22(3), 329-348. doi:10.1108/01443570210417623Brah, S. A., & Ying Lim, H. (2006). The effects of technology and TQM on the performance of logistics companies. International Journal of Physical Distribution & Logistics Management, 36(3), 192-209. doi:10.1108/09600030610661796Hervás Jorge, A., Ayats, J. C., Desantes, R., & Juliá, J. F. (2012). Las prácticas en empresa como uno de los ejes vertebradores de la empleabilidad. Revista Iberoamericana de Educación Superior. doi:10.22201/iisue.20072872e.2012.8.70Kass, G. V. (1980). An Exploratory Technique for Investigating Large Quantities of Categorical Data. Applied Statistics, 29(2), 119. doi:10.2307/2986296Kaiser, H. F. (1958). The varimax criterion for analytic rotation in factor analysis. Psychometrika, 23(3), 187-200. doi:10.1007/bf0228923

Professional Certifications of a University Master’s Degree and Employability: Impact on Students’ Perception

[Abstract]: Professional certifications represent for many university degrees, especially postgraduate degrees, a recognition of their academic quality and the future employability of the graduates. This article contributes to the analysis of the impact of external accreditations on students’ perception of employability and satisfaction. We offer a case of study, a Master of Science (MSc) in Banking and Finance that became the first academic degree in Spain to obtain the two professional accreditations required for employees in financial institutions since 2019. A survey to a sample of students who graduated two academic years before and two years after the MSc was recognised is used to measure students' motivations for enrolment and satisfaction. The results provide significant evidence that professional accreditation became a key motivation for students to enrol the master, is associated with a more diverse geographical origin of students, and students highlight the higher quality and better coordination of the teaching staff.R&D+i Program Oriented to Society’s Challenges ; PID2019-106273RBI0

Influencia de la competencia lingüística del profesorado en la implantación AICLE en Educación Física

The aim of this paper was to know the influence of the qualification level in the second foreign language in order to see the differences in teacher perception in Bilingual Physical Education classes (AICLE). For this, 146 active teachers in Physical Education participated in the present study, to whom the Physical Education Session Evaluation questionnaire (CESEFA) was administered through. Effects based on the sex of the participants and age category were also checked. The analysis of results showed that the participants who had a C1 level of English had a more positive perception of all categories analyzed. In turn, no differences were found based on the sex of the participants, but were found based on the age category, finding that those under 36 with a B2 level had a better perception of their classes in the items: take advantage of breaks, adaptation of content and feedback. It is concluded that the degree of qualification influences the perception of Physical Education classes, and that in the case of the youngest subjects, there are elements related to the individual efficacy variable, where no differences were found according to the degree of qualification or even these are positive in favor of level B2El objetivo de este trabajo fue conocer la influencia del nivel de calificación en la segunda lengua extranjera para ver las diferencias en la percepción del profesorado en las clases de Educación Física Bilingüe (AICLE). Para ello, en el presente estudio participaron 146 profesores activos de Educación Física, a quienes se les aplicó el cuestionario de Evaluación de Sesiones de Educación Física (CESEFA). También se comprobaron los efectos según el sexo de los participantes y la categoría de edad. El análisis de resultados mostró que los participantes que tenían un nivel C1 de inglés tenían una percepción más positiva de todas las categorías analizadas. A su vez, no se encontraron diferencias según el sexo de los participantes, pero sí según la categoría de edad, encontrando que los menores de 36 años con un nivel B2 tuvieron una mejor percepción de sus clases en los ítems: aprovechar descansos, adaptación de contenido y comentarios. Se concluye que el grado de calificación influye en la percepción de las clases de Educación Física, y que en el caso de los sujetos más jóvenes existen elementos relacionados con la variable eficacia individual, donde no se encontraron diferencias según el grado de calificación o incluso estos son positivos a favor del nivel B2.

Influencia de la competencia lingüística del profesorado en la implantación AICLE en Educación Física

The aim of this paper was to know the influence of the qualification level in the second foreign language in order to see the differences in teacher perception in Bilingual Physical Education classes (AICLE). For this, 146 active teachers in Physical Education participated in the present study, to whom the Physical Education Session Evaluation questionnaire (CESEFA) was administered through. Effects based on the sex of the participants and age category were also checked. The analysis of results showed that the participants who had a C1 level of English had a more positive perception of all categories analyzed. In turn, no differences were found based on the sex of the participants, but were found based on the age category, finding that those under 36 with a B2 level had a better perception of their classes in the items: take advantage of breaks, adaptation of content and feedback. It is concluded that the degree of qualification influences the perception of Physical Education classes, and that in the case of the youngest subjects, there are elements related to the individual efficacy variable, where no differences were found according to the degree of qualification or even these are positive in favor of level B2.El objetivo de este trabajo fue conocer la influencia del nivel de calificación en la segunda lengua extranjera para ver las diferencias en la percepción del profesorado en las clases de Educación Física Bilingüe (AICLE). Para ello, en el presente estudio participaron 146 profesores activos de Educación Física, a quienes se les aplicó el cuestionario de Evaluación de Sesiones de Educación Física (CESEFA). También se comprobaron los efectos según el sexo de los participantes y la categoría de edad. El análisis de resultados mostró que los participantes que tenían un nivel C1 de inglés tenían una percepción más positiva de todas las categorías analizadas. A su vez, no se encontraron diferencias según el sexo de los participantes, pero sí según la categoría de edad, encontrando que los menores de 36 años con un nivel B2 tuvieron una mejor percepción de sus clases en los ítems: aprovechar descansos, adaptación de contenido y comentarios. Se concluye que el grado de calificación influye en la percepción de las clases de Educación Física, y que en el caso de los sujetos más jóvenes existen elementos relacionados con la variable eficacia individual

Nuevos copolímeros a base de indol

Referencia OEPM: 9300155.-- Fecha de solicitud: 28/01/1993.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC).Nuevos copolímeros a base de indol (ver figura en archivo de texto adjunto). La presente invención se refiere a un nuevo tipo de copolímeros de base indol de fórmula general (I), en la que R puede ser los heterociclos tiofeno y pirrol, DP son restos del agente oxidante que actúa como agente dopante. Para la obtención de los copolímeros se hace reaccionar indol con los heterociclos tiofeno o pirrol preferentemente a temperatura entre 25-30ºC en presencia de agente oxidante tal como el cloruro férrico, disueltos en cloroformo. En ambos casos se utilizan distintas relaciones molares de oxidante/monómero entre 1.5 y 5 y de comonómero/indol entre 1.5 y 9. Al final de la reacción se precipita el copolímero con una mezcla metanol/agua (1:1 en peso). Estos polímeros se caracterizan por presentar una marcada conductividad eléctrica y ser fácilmente solubles, lo que les hace ser aptos para diversas aplicaciones como conductores.Peer reviewe