Instalación eléctrica de una residencia de ancianos

Instalación eléctrica de una residencia de ancianos ubicada en Maella

Creación y puesta en marcha de una empresa. Aplicación a "Holydreams, vacaciones sin maletas"

[ES] Creación y puesta en marcha de una empresa del sector servicios y análisis de la viabilidad económica del proyecto.[EN] Creation and start-up of a company in the services sector and analysis of the economic viability of the project.Morales Aznar, R. (2018). Creación y puesta en marcha de una empresa. Aplicación a "HOLYDREAMS, vacaciones sin maletas". http://hdl.handle.net/10251/106348TFG

Fracture test of a Gothic ribbed vault

A Gothic ribbed vault has been built at the School of Architecture of Madrid in order to investigate the construction complexities of this kind of vaults. The ribbed vault is described in the manuscript of Alonso de Vandelvira, and its shape was reconstructed making using the drawings this architect from the 16th century. The fracture test was carried on by loading the central keystone of the vault until its collapse took place. The experiment was filmed and by doing so, it was possible to observe the failure mechanism of the vault. At the same time, it was interesting to compare this collapse experience with the results obtained using two different me-thods. First, a stability calculation was carried out through graphic statics, and secondly a calcu-lation was performed using the rigid-block analysis method. The focus of this paper is to show and analyze the results of both studies

An Alternate Representation of the Vector of Apparent Power and Unbalanced Power in Three-Phase Electrical Systems

[EN] Low-voltage distribution systems are typically unbalanced. These ine¿ciencies cause unbalanced powers that can significantly increase the apparent power of the system. Analysing and measuring these ine¿cient powers appropriately allows us to compensate for them and obtain a more e¿cient system. Correcting the imbalance at some nodes can worsen the rest of the system; therefore, it is essential that all nodes are analysed such that action can be taken when necessary. In most studies, the unbalanced power is measured from the modulus. Other more recent studies have proposed phasor expressions of unbalanced powers; however, in both cases, these are not enough to address the compensation of unbalanced powers in systems with unbalanced voltages. In this work, a di¿erent representation of the vector expressions for analysis of the unbalanced powers and the apparent powers of the three-phase linear systems is proposed. Additionally, these vector expressions are extended to nonlinear systems to quantify the harmonic apparent powers. These expressions have been formulated from the power of Buchholz and are valid for systems with unbalanced voltages and currents. To help understand the use of the proposed formulation, a practical case of a three-phase four-wire system with unbalanced loads and voltages is demonstrated.This work is supported by the Spanish Ministry of Science, Innovation and Universities (MICINN) and the European Regional Development Fund (ERDF) under Grant RTI2018-100732-B-C21.Blasco Espinosa, PA.; Montoya-Mira, R.; Diez-Aznar, J.; Montoya Villena, R. (2020). An Alternate Representation of the Vector of Apparent Power and Unbalanced Power in Three-Phase Electrical Systems. Applied Sciences. 10(11):1-16. https://doi.org/10.3390/app10113756S1161011Emanuel, A. E. (1993). On the definition of power factor and apparent power in unbalanced polyphase circuits with sinusoidal voltage and currents. IEEE Transactions on Power Delivery, 8(3), 841-852. doi:10.1109/61.252612Willems, J. L. (2004). Reflections on Apparent Power and Power Factor in Nonsinusoidal and Polyphase Situations. IEEE Transactions on Power Delivery, 19(2), 835-840. doi:10.1109/tpwrd.2003.823182Emanuel, A. E. (1999). Apparent power definitions for three-phase systems. IEEE Transactions on Power Delivery, 14(3), 767-772. doi:10.1109/61.772313Czarnecki, L. S. (1994). Misinterpretations of some power properties of electric circuits. IEEE Transactions on Power Delivery, 9(4), 1760-1769. doi:10.1109/61.329509Kersting, W. H. (2001). Causes and effects of unbalanced voltages serving an induction motor. IEEE Transactions on Industry Applications, 37(1), 165-170. doi:10.1109/28.903142Pillay, P., & Manyage, M. (2006). Loss of Life in Induction Machines Operating With Unbalanced Supplies. IEEE Transactions on Energy Conversion, 21(4), 813-822. doi:10.1109/tec.2005.853724Poblador, M. L. A., & Lopez, G. A. R. (2013). Power calculations in nonlinear and unbalanced conditions according to IEEE Std 1459-2010. 2013 Workshop on Power Electronics and Power Quality Applications (PEPQA). doi:10.1109/pepqa.2013.6614957Langella, R., Testa, A., & Emanuel, A. E. (2012). Unbalance Definition for Electrical Power Systems in the Presence of Harmonics and Interharmonics. IEEE Transactions on Instrumentation and Measurement, 61(10), 2622-2631. doi:10.1109/tim.2012.2209909Kukačka, L., Kraus, J., Kolář, M., Dupuis, P., & Zissis, G. (2016). Review of AC power theories under stationary and non‐stationary, clean and distorted conditions. IET Generation, Transmission & Distribution, 10(1), 221-231. doi:10.1049/iet-gtd.2015.0713Chicco, G., Postolache, P., & Toader, C. (2007). Analysis of Three-Phase Systems With Neutral Under Distorted and Unbalanced Conditions in the Symmetrical Component-Based Framework. IEEE Transactions on Power Delivery, 22(1), 674-683. doi:10.1109/tpwrd.2006.887095Paap, G. C. (2000). Symmetrical components in the time domain and their application to power network calculations. IEEE Transactions on Power Systems, 15(2), 522-528. doi:10.1109/59.867135León-Martínez, V., & Montañana-Romeu, J. (2018). Formulations for the apparent and unbalanced power vectors in three-phase sinusoidal systems. Electric Power Systems Research, 160, 37-43. doi:10.1016/j.epsr.2018.01.028Castilla, M., Bravo, J. C., Ordonez, M., & Montano, J. C. (2008). Clifford Theory: A Geometrical Interpretation of Multivectorial Apparent Power. IEEE Transactions on Circuits and Systems I: Regular Papers, 55(10), 3358-3367. doi:10.1109/tcsi.2008.924885Diez, J. M., Blasco, P. A., & Montoya, R. (2016). Formulation of phasor unbalance power: application to sinusoidal power systems. IET Generation, Transmission & Distribution, 10(16), 4178-4186. doi:10.1049/iet-gtd.2016.0730Tongxin Zheng, Makram, E. B., & Girgis, A. A. (2003). Evaluating power system unbalance in the presence of harmonic distortion. IEEE Transactions on Power Delivery, 18(2), 393-397. doi:10.1109/tpwrd.2002.807460Mohamadian, S., & Shoulaie, A. (2011). Comprehensive Definitions for Evaluating Harmonic Distortion and Unbalanced Conditions in Three- and Four-Wire Three-Phase Systems Based on IEEE Standard 1459. IEEE Transactions on Power Delivery, 26(3), 1774-1782. doi:10.1109/tpwrd.2011.2126609Blasco, P. A., Montoya-Mira, R., Diez, J. M., Montoya, R., & Reig, M. J. (2019). Compensation of Reactive Power and Unbalanced Power in Three-Phase Three-Wire Systems Connected to an Infinite Power Network. Applied Sciences, 10(1), 113. doi:10.3390/app10010113Montoya-Mira, R., Blasco, P. A., Diez, J. M., Montoya, R., & Reig, M. J. (2020). Unbalanced and Reactive Currents Compensation in Three-Phase Four-Wire Sinusoidal Power Systems. Applied Sciences, 10(5), 1764. doi:10.3390/app10051764Salmerón, P., Vázquez, J. R., Herrera, R. S., & Litrán, S. P. (2007). Apparent power and power factor in unbalanced and distorted systems. Applications in three phase load compensations. Renewable Energy and Power Quality Journal, 1(05), 442-447. doi:10.24084/repqj05.31

Comparing the Min–Max–Median/IQR Approach with the Min–Max Approach, Logistic Regression and XGBoost, maximising the Youden index

Although linearly combining multiple variables can provide adequate diagnostic performance, certain algorithms have the limitation of being computationally demanding when the number of variables is sufficiently high. Liu et al. proposed the min–max approach that linearly combines the minimum and maximum values of biomarkers, which is computationally tractable and has been shown to be optimal in certain scenarios. We developed the Min–Max–Median/IQR algorithm under Youden index optimisation which, although more computationally intensive, is still approachable and includes more information. The aim of this work is to compare the performance of these algorithms with well-known Machine Learning algorithms, namely logistic regression and XGBoost, which have proven to be efficient in various fields of applications, particularly in the health sector. This comparison is performed on a wide range of different scenarios of simulated symmetric or asymmetric data, as well as on real clinical diagnosis data sets. The results provide useful information for binary classification problems of better algorithms in terms of performance depending on the scenario

On the behavior of the Sierpinski multiband fractal antenna

The multiband behavior of the fractal Sierpinski antenna is described. Due to its mainly triangular shape, the antenna is compared to the well-known single-band bow-tie antenna. Both experimental and numerical results show that the self-similarity properties of the fractal shape are translated into its electromagnetic behavior. A deeper physical insight on such a behavior is achieved by means of the computed current densities over the antenna surface, which also display some similarity properties through the bands.Peer Reviewe

Unbalanced and Reactive Currents Compensation in Three-Phase Four-Wire Sinusoidal Power Systems

[EN] In an unbalanced linear three-phase electrical system, there are inefficient powers that increase the apparent power supplied by the network, line losses, machine malfunctions, etc. These inefficiencies are mainly due to the use of unbalanced loads. Unlike a three-wire unbalanced system, a four-wire system has zero sequence currents that circulate through the neutral wire and can be compensated by means of compensation equipment, which prevents it from being delivered by the network. To design a compensator that works with unbalanced voltages, it is necessary to consider the interactions between it and the other compensators used to compensate for negative-sequence currents and positive-sequence reactive currents. In this paper, through passive compensation, a new method is proposed to develop the zero sequence current compensation equipment. The method does not require iteration algorithms and is valid for unbalanced voltages. In addition, the interactions between all compensators are analyzed, and the necessary modifications in the calculations are proposed to obtain a total compensation. To facilitate the application of the method and demonstrate its validity, a case study is developed from a three-phase linear four-wire system with unbalanced voltages and loads. The results obtained are compared with other compensation methods that also use passive elements.This work is supported by the Spanish Ministry of Science, Innovation and Universities (MICINN) and the European Regional Development Fund (ERDF) under grant RTI2018-100732-B-C21.Montoya-Mira, R.; Blasco Espinosa, PA.; Diez-Aznar, J.; Montoya Villena, R.; Reig-Pérez, MJ. (2020). Unbalanced and Reactive Currents Compensation in Three-Phase Four-Wire Sinusoidal Power Systems. Applied Sciences. 10(5):1-23. https://doi.org/10.3390/app10051764S123105Sainz, L., Caro, M., & Caro, E. (2009). Analytical Study of the Series Resonance in Power Systems With the Steinmetz Circuit. IEEE Transactions on Power Delivery, 24(4), 2090-2098. doi:10.1109/tpwrd.2009.2028790Emanuel, A. E. (1993). On the definition of power factor and apparent power in unbalanced polyphase circuits with sinusoidal voltage and currents. IEEE Transactions on Power Delivery, 8(3), 841-852. doi:10.1109/61.252612Willems, J. L. (2004). Reflections on Apparent Power and Power Factor in Nonsinusoidal and Polyphase Situations. IEEE Transactions on Power Delivery, 19(2), 835-840. doi:10.1109/tpwrd.2003.823182Pillay, P., & Manyage, M. (2006). Loss of Life in Induction Machines Operating With Unbalanced Supplies. IEEE Transactions on Energy Conversion, 21(4), 813-822. doi:10.1109/tec.2005.853724Poblador, M. L. A., & Lopez, G. A. R. (2013). Power calculations in nonlinear and unbalanced conditions according to IEEE Std 1459-2010. 2013 Workshop on Power Electronics and Power Quality Applications (PEPQA). doi:10.1109/pepqa.2013.6614957IEEE Recommended Practice for Monitoring Electric Power Quality. (s. f.). doi:10.1109/ieeestd.2019.8796486Blasco, P. A., Montoya-Mira, R., Diez, J. M., Montoya, R., & Reig, M. J. (2019). Compensation of Reactive Power and Unbalanced Power in Three-Phase Three-Wire Systems Connected to an Infinite Power Network. Applied Sciences, 10(1), 113. doi:10.3390/app10010113San-Yi Lee, & Chi-Jui Wu. (1993). On-line reactive power compensation schemes for unbalanced three phase four wire distribution feeders. IEEE Transactions on Power Delivery, 8(4), 1958-1965. doi:10.1109/61.248308Otto, R. A., Putman, T. H., & Gyugyi, L. (1978). Principles and Applications of Static, Thyristor-Controlled Shunt Compensators. IEEE Transactions on Power Apparatus and Systems, PAS-97(5), 1935-1945. doi:10.1109/tpas.1978.354690Origa de Oliveira, L. C., Barros Neto, M. C., & de Souza, J. B. (s. f.). Load compensation in four-wire electrical power systems. PowerCon 2000. 2000 International Conference on Power System Technology. Proceedings (Cat. No.00EX409). doi:10.1109/icpst.2000.898206Li, E., Sheng, W., Wang, X., & Wang, B. (2011). Combined compensation strategies based on instantaneous reactive power theory for reactive power compensation and load balancing. 2011 International Conference on Electrical and Control Engineering. doi:10.1109/iceceng.2011.6057765Leon-Martinez, V., & Montanana-Romeu, J. (2014). Representation of load imbalances through reactances. Application to working standards. 2014 16th International Conference on Harmonics and Quality of Power (ICHQP). doi:10.1109/ichqp.2014.6842894Czarnecki, L. S., & Haley, P. M. (2015). Unbalanced Power in Four-Wire Systems and Its Reactive Compensation. IEEE Transactions on Power Delivery, 30(1), 53-63. doi:10.1109/tpwrd.2014.2314599Czarnecki, L. S. (1989). Reactive and unbalanced currents compensation in three-phase asymmetrical circuits under nonsinusoidal conditions. IEEE Transactions on Instrumentation and Measurement, 38(3), 754-759. doi:10.1109/19.32187Czarnecki, L. S. (1988). Orthogonal decomposition of the currents in a 3-phase nonlinear asymmetrical circuit with a nonsinusoidal voltage source. IEEE Transactions on Instrumentation and Measurement, 37(1), 30-34. doi:10.1109/19.2658Pană, A., Băloi, A., & Molnar-Matei, F. (2018). From the Balancing Reactive Compensator to the Balancing Capacitive Compensator. Energies, 11(8), 1979. doi:10.3390/en1108197

Enseñanza del sistema de numeración decimal en primer curso de educación primaria

En este trabajo de fin de grado, se expone un estudio sobre la enseñanza del Sistema de Numeración Decimal (SND) en un aula de primer curso de Educación Primaria del colegio Sagrado Corazón-Moncayo en Zaragoza. A lo largo del mismo se profundiza en el contenido matemático asociado al SND, caracterizando los momentos iniciales de la enseñanza actual del SND a partir del análisis de libro de texto que siguen en el colegio donde se va a realizar la parte experimental de este trabajo. Posteriormente, estudiamos las dificultades de aprendizaje de un grupo- clase de primer curso de Educación Primaria que ha recibido previamente enseñanza del SND a partir de los resultados obtenidos en una prueba inicial diagnostica y, finalmente, se diseña, desarrolla y evalúa una propuesta parcial de enseñanza en ese grupo natural de primer curso de Educación Primaria

Improving the energy efficiency of slightly inductive three-phase three-wire linear systems through single-phase capacitors banks

[EN] Recent low-voltage, three-phase distribution networks carry inefficient power, which can be attributed to the reactive power, imbalance of linear loads, and increase in non-linear loads. Researchers have mainly focused on developing active filters to improve the quality of electrical energy. However, in most cases, compensating for the reactive power is sufficient, considering cost and quality. Active filters are expensive, thus, passive compensators are more appealing. These devices are composed of single-phase or three-phase capacitor banks that act on the reactive power consumed by the load. The operation of these devices has been sufficiently validated owing to their long-term use. For unbalanced power, compensators that contain coils are used. A methodology to obtain compensators comprising only single-phase capacitors for the inductive reactive power consumed by the load is presented here; if designed appropriately, these compensators can compensate for a part of or the entire unbalanced power, resulting in greater efficiency in the transfer of electrical energy.Spanish Ministry of Science, Innovation, and Universities (MICINN); European Regional Development Fund (ERDF), Grant/AwardNumber: RTI2018100732-B-C21Blasco Espinosa, PA.; Montoya-Mira, R.; Diez-Aznar, J.; Montoya Villena, R.; Garcerá, G.; Figueres Amorós, E. (2022). Improving the energy efficiency of slightly inductive three-phase three-wire linear systems through single-phase capacitors banks. IET Generation Transmission & Distribution. 16(6):1212-1224. https://doi.org/10.1049/gtd2.12361S1212122416

La protección de la mujer frente al mobbing y el acoso sexual laboral

En el ámbito laboral existen diferentes tipos de riesgos: los físicos, a los que se suele atender de manera principal, y otros de carácter psicológico y moral. Hoy en día la salud de los trabajadores, en general , y la de las mujeres trabajadoras, en particular, se ve amenazada por la presencia de estos riesgos, siendo uno de los principales peligros el acoso en sus distintas variantes: sexual, moral, por razón de sexo, etc., que a su vez pueden provenir del propio empresario, pero también de otros trabajadores de la empresa.. Es por esto que existen diferentes normativas y protocolos con intención de proteger a la mujer, que, como ya he dicho, en muchas ocasiones va a ser la principal víctima de este tipo de conductas. Aunque la labor preventiva es una de las claves, es evidente que en muchas ocasiones no se van a poder evitar estos comportamientos, por lo que el ordenamiento jurídico también ofrece una serie de mecanismos de tutela a quienes han sufrido acoso en el medio laboral. A lo largo de este trabajo se van a analizar el concepto y los distintos tipos de acoso, las normas y medidas preventivas para evitar estos daños, así como los diferentes mecanismos de tutela que se le ofrecen a la víctima, junto con las sanciones y consecuencias jurídicas para el agresor.<br /