Critical velocity in kink solutions of the sine-Gordon equation

The goal of this work is to present a way to deduce the value of the critical velocity observed in soliton-like solutions of a perturbed version of the sine-Gordon equation. To do so, an ODE system is obtained from the perturbed sine-Gordon equation using a variational approach; the resulting Hamiltonian system is then studied. From that, a Melnikov integral formula for the critical velocity is deduced via an energy balance reasoning. Finally, the problem is approached from a geometrical point of view that allows for an interpretation of the previous results in terms of intersections of invariant manifolds of periodic orbits

Safety-informed design of lead-cooled reactors on mobile platforms

Nuclear power has a prominent role to play in the energy landscape of the 21st century. To- gether with large reactor designs that make the most out of economies of scale, small, modular reactors (SMR) may also play a role thanks to their potential modular, factory-based and fast deployment, which have the potential to minimize the capital cost of nuclear, which is one of its main drawbacks. Among such designs, lead-cooled fast reactors (LFR) present some unique strengths, among others their lack of pressurization of the primary system and their potential to passively remove decay heat by means of natural convection. The SUNRISE project, in Sweden, is an effort by, among others, KTH to prove the feasability of this technology. In that context, the analytical design tool ADELE, which draws from the BELLA code produced at KTH, is developed. Its goal is to provide a fast-to-iterate algorithm that uses basic physics constraints to obtain the core design without relying on more computationally costly methods, like Monte Carlo simulations, which are regularly used for that purpose. Specifically, a system that is capable of removing all the residual heat via convective cooling is obtained from a short list of basic input values. This algorithm is implemented into a mobile application, with the goal of being available to Nuclear Engineering students. The resulting code is capable of replicating reference core designs with a reasonable degree of accuracy, given the simplicity of the assumptions used in the process

A structural study of the behavior of bumper cars compared to a system of spatially uncorrelated hard disks

2014/201

Causas de la no selección del boxeo olímpico por parte del profesorado en las clases de secundaria

This work is part of a broader research attempts to analyze the presence of combat sports in Secondary Education. The study investigates the presence of boxing in the teaching programs of the faculty, and the factors that influence their choice, based on what they know, what they think and what they need on this modality. The instrument used was a questionnaire sent via online to active Physical Education faculty in secondary schools of Valencian Community (Spain), which was answered by 81 teachers. From the results highlights that faculty choose team sports such as basketball, handball and volleyball, but they are very few that include in their programming combat sports, judo being the most chosen. The main factors that justify their limited presence refer to the teacher is not able to impart a teaching unit about these topic, who consider him dangerous, risky and unsuitable for work in values. They mark that they need more specialized teaching materials in the initiation and further training in the basics of fighting.El presente trabajo es parte de una investigación más amplia que analiza la presencia de los deportes de combate en la Educación Secundaria. Este estudio indaga la presencia del boxeo en las programaciones didácticas del profesorado, así como qué factores condicionan su elección, en base a qué sabe, qué piensa y qué necesita sobre dicha modalidad. El instrumento utilizado fue un cuestionario enviado vía online al profesorado en activo de Educación Física en los centros de Educación Secundaria de la Comunidad Valenciana (España), el cual fue respondido por 81 profesores. De los resultados obtenidos se destaca que la mayoría del profesorado elige deportes colectivos como baloncesto, balonmano y voleibol, sin embargo, son muy pocos los que incluyen en su programación deportes de combate, siendo el judo el más elegido. Los principales factores que justifican su escasa presencia hacen referencia a que el profesorado no se ve capaz de impartir una Unidad Didáctica sobre el tema ya que lo consideran peligroso, arriesgado y poco adecuado para el trabajo en valores. Señalan que necesitan más material didáctico especializado en la iniciación y mayor formación en los fundamentos básicos de la lucha.Ciencias de la Actividad Física y del Deport

Modelling human behaviour in a bumper car ride using molecular dynamics tools: a student project

Amusement parks are excellent laboratories of physics, not only to check physical laws, but also to investigate if those physical laws might also be applied to human behaviour. A group of Physics Engineering students from Universitat Politècnica de Catalunya has investigated if human behaviour, when driving bumper cars, can be modelled using tools borrowed from the analysis of molecular dynamics simulations, such as the radial and angular distribution functions. After acquiring several clips and obtaining the coordinates of the cars, those magnitudes are computed and analysed. Additionally, an analogous hard disks system is simulated to compare its distribution functions to those obtained from the cars' coordinates. Despite the clear difference between bumper cars and a hard disk-like particle system, the obtained distribution functions are very similar. This suggests that there is no important effect of the individuals in the collective behaviour of the system in terms of structure. The research, performed by the students, has been undertaken in the frame of a motivational project designed to approach the scientific method for university students named FISIDABO. This project offers both the logistical and technical support to undertake the experiments designed by students at the amusement park of Barcelona TIBIDABO and accompanies them all along the scientific process.Postprint (published version

Dataciones radiocarbónicas de la Cova de la Sarsa (Bocairent, València)

La revisión de los materiales arqueológicos recuperados en la Cova de la Sarsa nos ha llevado a establecer una serie de propuestas sobre sus diferentes ocupaciones y su funcionalidad. En relación con estos estudios se han seleccionado una serie de muestras para su datación por radiocarbono. Presentamos los resultados de dichas dataciones. La revisió dels materials arqueològics recuperats en la Cova de la Sarsa ens ha portat a establir una série de propostes sobre les seues diferents ocupacions i la seua funcionalitat. En relació amb aquests estudis s"han seleccionat una série de mostres per a la seua datació per radiocarbon. Presentem els resultats de les dites datacions. The revision of the archaeological materials recovered from Cova de la Sarsa has enabled us to put forward several proposals regarding the site"s occupation and functionality. In order to better assess these materials, eight bone samples have been chosen for radiocarbon dating. In this paper we present and discuss these results

Factors affecting the presence of wrestling in school programs

This work is part of a broader research that attempts to analyse the presence of combat sports in secondary education. The study investigates the presence of Olympic wrestling in the curricula of teacher preparation programs, as well as the factors influencing the choice, based on the knowledge, perspective and the needs about these disciplines. Eighty-one active physical education (PE) teachers of Valencia’s secondary schools completed an online questionnaire (51 men and 30 women). Results highlight that most of the teachers select team sports such as basketball, handball and volleyball; however, only a few included combat sports in their program, with judo being the most frequently selected. The main factor justifying the scarcity of combative sports, refers to the fact that teachers are not able to provide an instructional unit, and that these activities are considered dangerous, risky and unsuitable to instructional values. These viewpoints indicate that more specialized instructional tools for basic education in the fundamentals of combative sports, including wrestling are needed.Ciencias de la Actividad Física y del Deport

Dataciones radiocarbónicas de la Cova de la Sarsa (Bocairent, València)

La revisión de los materiales arqueológicos recuperados en la Cova de la Sarsa nos ha llevado a establecer una serie de propuestas sobre sus diferente

Irrigation Post-Modernization. Farmers Envisioning Irrigation Policy in the Region of Valencia (Spain)

[EN] During the last three decades, like many other Mediterranean states, Spain has intensively promoted the modernization of irrigation, focusing mainly on the introduction of pressurized irrigation systems. Following 30 years of investment, a shift in irrigation policies is needed to solve some of the deficiencies in this modernization process and to incorporate new measures to cope with upcoming challenges generated by international markets, climate change and other social and economic processes. This paper describes and analyses the results of participatory research carried out with the water user associations in the autonomous region of Valencia, in order to define post-modernization irrigation policies. A survey and 24 local workshops involving 304 water user associations were conducted during the irrigation season of 2018 in order to form an assessment of the sector and design new irrigation policies. The results show that after 30 years of important investment, the obsolescence of the infrastructure has become the current main priority, making farmers dependent on public subsidies. New necessities have also emerged, such as renewable energies and nonconventional water resources, which farmers consider indispensable in order to reduce operating costs and guarantee water supply.This work has been developed under the framework of the research agreement "Estudio para la modernizacion del regadio en la Comunidad Valenciana", between the Universitat Politecnica de Valencia and the Generalitat Valenciana, and conducted as part of the research project "Design and evaluation of strategies to adapt to global climate change in Mediterranean watersheds by using irrigation water intensively (ADAPTAMED)" (RTI2018-101483-B-I00), funded by the Ministerio de Economia y Competitividad (MINECO) of Spain and with EU FEDER funds.Sanchis Ibor, C.; Ortega-Reig, M.; Guillem-Garcia, A.; Carricondo, JM.; Manzano Juarez, J.; García Molla, M.; Royuela, A. (2021). Irrigation Post-Modernization. Farmers Envisioning Irrigation Policy in the Region of Valencia (Spain). Agriculture. 11(4):1-21. https://doi.org/10.3390/agriculture11040317S121114Siebert, S., Kummu, M., Porkka, M., Döll, P., Ramankutty, N., & Scanlon, B. R. (2015). A global data set of the extent of irrigated land from 1900 to 2005. Hydrology and Earth System Sciences, 19(3), 1521-1545. doi:10.5194/hess-19-1521-2015Projects in Irrigation and Drainage https://projects.worldbank.org/en/projects-operations/projects-list?sectorcode_exact=AIInternational Commission on Irrigation and Drainage (ICID), World Irrigated Area 2018 https://www.icid.org/world-irrigated-area.pdfBenouniche, M., Zwarteveen, M., & Kuper, M. (2014). BRICOLAGEAS INNOVATION: OPENING THE BLACK BOX OF DRIP IRRIGATION SYSTEMS. Irrigation and Drainage, 63(5), 651-658. doi:10.1002/ird.1854Van der Kooij, S., Zwarteveen, M., & Kuper, M. (2015). The material of the social: the mutual shaping of institutions by irrigation technology and society in Seguia Khrichfa, Morocco. International Journal of the Commons, 9(1), 129. doi:10.18352/ijc.539Ortega-Reig, M., Sanchis-Ibor, C., Palau-Salvador, G., García-Mollá, M., & Avellá-Reus, L. (2017). Institutional and management implications of drip irrigation introduction in collective irrigation systems in Spain. Agricultural Water Management, 187, 164-172. doi:10.1016/j.agwat.2017.03.009García-Mollá, M., Ortega-Reig, M., Boelens, R., & Sanchis-Ibor, C. (2020). Hybridizing the commons. Privatizing and outsourcing collective irrigation management after technological change in Spain. World Development, 132, 104983. doi:10.1016/j.worlddev.2020.104983Lecina, S., Isidoro, D., Playán, E., & Aragüés, R. (2010). Irrigation Modernization in Spain: Effects on Water Quantity and Quality—A Conceptual Approach. International Journal of Water Resources Development, 26(2), 265-282. doi:10.1080/07900621003655734Berbel, J., & Mateos, L. (2014). Does investment in irrigation technology necessarily generate rebound effects? A simulation analysis based on an agro-economic model. Agricultural Systems, 128, 25-34. doi:10.1016/j.agsy.2014.04.002Berbel, J., Gutiérrez-Martín, C., Rodríguez-Díaz, J. A., Camacho, E., & Montesinos, P. (2014). Literature Review on Rebound Effect of Water Saving Measures and Analysis of a Spanish Case Study. Water Resources Management, 29(3), 663-678. doi:10.1007/s11269-014-0839-0Berbel, J., Gutiérrez-Martín, C., & Expósito, A. (2018). Impacts of irrigation efficiency improvement on water use, water consumption and response to water price at field level. Agricultural Water Management, 203, 423-429. doi:10.1016/j.agwat.2018.02.026Molle, F., & Tanouti, O. (2017). Squaring the circle: Agricultural intensification vs. water conservation in Morocco. Agricultural Water Management, 192, 170-179. doi:10.1016/j.agwat.2017.07.009Pérez-Blanco, C. D., Hrast-Essenfelder, A., & Perry, C. (2020). Irrigation Technology and Water Conservation: A Review of the Theory and Evidence. Review of Environmental Economics and Policy, 14(2), 216-239. doi:10.1093/reep/reaa004Rodríguez-Díaz, J. A., Pérez-Urrestarazu, L., Camacho-Poyato, E., & Montesinos, P. (2011). The paradox of irrigation scheme modernization: more efficient water use linked to higher energy demand. Spanish Journal of Agricultural Research, 9(4), 1000. doi:10.5424/sjar/20110904-492-10Rocamora, C., Vera, J., & Abadía, R. (2012). Strategy for Efficient Energy Management to solve energy problems in modernized irrigation: analysis of the Spanish case. Irrigation Science, 31(5), 1139-1158. doi:10.1007/s00271-012-0394-5Espinosa-Tasón, J., Berbel, J., & Gutiérrez-Martín, C. (2020). Energized water: Evolution of water-energy nexus in the Spanish irrigated agriculture, 1950–2017. Agricultural Water Management, 233, 106073. doi:10.1016/j.agwat.2020.106073Lopez-Gunn, E., Zorrilla, P., Prieto, F., & Llamas, M. R. (2012). Lost in translation? Water efficiency in Spanish agriculture. Agricultural Water Management, 108, 83-95. doi:10.1016/j.agwat.2012.01.005Garb, Y., & Friedlander, L. (2014). From transfer to translation: Using systemic understandings of technology to understand drip irrigation uptake. Agricultural Systems, 128, 13-24. doi:10.1016/j.agsy.2014.04.003Venot, J.-P., Zwarteveen, M., Kuper, M., Boesveld, H., Bossenbroek, L., Kooij, S. V. D., … Verma, S. (2014). BEYOND THE PROMISES OF TECHNOLOGY: A REVIEW OF THE DISCOURSES AND ACTORS WHO MAKE DRIP IRRIGATION. Irrigation and Drainage, 63(2), 186-194. doi:10.1002/ird.1839Soto-García, M., Martínez-Alvarez, V., García-Bastida, P. A., Alcon, F., & Martin-Gorriz, B. (2013). Effect of water scarcity and modernisation on the performance of irrigation districts in south-eastern Spain. Agricultural Water Management, 124, 11-19. doi:10.1016/j.agwat.2013.03.019Playán, E., Salvador, R., López, C., Lecina, S., Dechmi, F., & Zapata, N. (2014). Solid-Set Sprinkler Irrigation Controllers Driven by Simulation Models: Opportunities and Bottlenecks. Journal of Irrigation and Drainage Engineering, 140(1), 04013001. doi:10.1061/(asce)ir.1943-4774.0000653Tarjuelo, J. M., Rodriguez-Diaz, J. A., Abadía, R., Camacho, E., Rocamora, C., & Moreno, M. A. (2015). Efficient water and energy use in irrigation modernization: Lessons from Spanish case studies. Agricultural Water Management, 162, 67-77. doi:10.1016/j.agwat.2015.08.009Informe Del Sector Agrari Valencià 2019: València: Generalitat Valenciana 2021 http://www.agroambient.gva.es/va/informes-del-sector-agrario-valencianoPlan Hidrológico de la Cuenca Del Júcar 2015–2021 https://www.chj.es/es-es/medioambiente/planificacionhidrologica/Paginas/PHC-2015–2021-Plan-Hidrologico-cuenca.aspxPlan Hidrológico de la Demarcación Del Segura 2015–2021 https://www.chsegura.es/es/cuenca/planificacion/planificacion-2015–2021/plan-hidrologico-2015–2021/index.htmlMaster Plan for the Modernization of Irrigation in the Valencia Region, DECRETO 13/1995 de 10 de Enero, Del Gobierno Valenciano, Por El Que Se Aprueba El Plan Director de Modernización Del Regadío de la Comunidad http://www.dogv.gva.es/portal/ficha_disposicion_pc.jsp?sig=0185/1995&L=1Scheierling, S. M., Young, R. A., & Cardon, G. E. (2006). Public subsidies for water-conserving irrigation investments: Hydrologic, agronomic, and economic assessment. Water Resources Research, 42(3). doi:10.1029/2004wr003809Ward, F. A., & Pulido-Velazquez, M. (2008). Water conservation in irrigation can increase water use. Proceedings of the National Academy of Sciences, 105(47), 18215-18220. doi:10.1073/pnas.0805554105Pfeiffer, L., & Lin, C.-Y. C. (2014). Does efficient irrigation technology lead to reduced groundwater extraction? Empirical evidence. Journal of Environmental Economics and Management, 67(2), 189-208. doi:10.1016/j.jeem.2013.12.002Dagnino, M., & Ward, F. A. (2012). Economics of Agricultural Water Conservation: Empirical Analysis and Policy Implications. International Journal of Water Resources Development, 28(4), 577-600. doi:10.1080/07900627.2012.665801A Blueprint to Safeguard Europe’s Water Resources, Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions 2012 https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:52012DC0673&from=ENSanchis-Ibor, C., García-Mollá, M., & Avellà-Reus, L. (2016). Effects of drip irrigation promotion policies on water use and irrigation costs in Valencia, Spain. Water Policy, 19(1), 165-180. doi:10.2166/wp.2016.025LIU, B., MEI, X., LI, Y., & YANG, Y. (2007). The Connotation and Extension of Agricultural Water Resources Security. Agricultural Sciences in China, 6(1), 11-16. doi:10.1016/s1671-2927(07)60011-xMalekian, A., Hayati, D., & Aarts, N. (2017). Conceptualizations of water security in the agricultural sector: Perceptions, practices, and paradigms. Journal of Hydrology, 544, 224-232. doi:10.1016/j.jhydrol.2016.11.026Swyngedouw, E. (2013). Into the Sea: Desalination as Hydro-Social Fix in Spain. Annals of the Association of American Geographers, 103(2), 261-270. doi:10.1080/00045608.2013.754688Swyngedouw, E., & Williams, J. (2016). From Spain’s hydro-deadlock to the desalination fix. Water International, 41(1), 54-73. doi:10.1080/02508060.2016.1107705Análisis y Evaluación de Las Relaciones Entre El Agua y la Energía, Papeles de Agua Virtual 6, Madrid: Fundación Botín https://www.fundacionbotin.org/89dguuytdfr276ed_uploads/Observatorio%20Tendencias/PUBLICACIONES/MONOGRAFIAS/PAV/PAV6.pdfHardy, L., Garrido, A., & Juana, L. (2012). Evaluation of Spain’s Water-Energy Nexus. International Journal of Water Resources Development, 28(1), 151-170. doi:10.1080/07900627.2012.642240Mayor, B., López-Gunn, E., Villarroya, F. I., & Montero, E. (2015). Application of a water–energy–food nexus framework for the Duero river basin in Spain. 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On the Need to Further Refine Stock Quality Specifications to Improve Reforestation under Climatic Extremes

[EN] The achievement of goals in forest landscape restoration strongly relies on successful plantation establishment, which is challenging in drylands, especially under climate change. Improvement of field performance through stock quality has been used for decades. Here, we use machine learning (ML) techniques to identify key stock traits involved in successful survival and to refine previous specifications that were developed under more conventional stock quality assessments carried out at the lifting-shipping phases in the nursery. Two differentiated stocklots in each species were used, both fitting in the regional quality standard. ML was used to infer a set of attributes for planted seedlings that were subsequently related to survival at the short-term (two years) and mid-term (ten years) in six different species planted in a harsh site with shallow soil that suffered the driest year on record during this study. Whilst stocklot quality, as measured in the lifting-shipping stage, had very poor importance to the survival response, individual plant traits presented a moderate to high diagnostic ability for seedling survival (area under the receiver operating characteristic (ROC) curve between 0.59 and 0.99). Early growth traits catch most of the importance in these models (approximate to 40%), followed by individual morphology traits (approximate to 28%) and site variation (approximate to 2%), with overall means varying across species. Aleppo pine and Phoenician juniper stocklots presented survival rates of 66-78% after ten years, and these rates were below 27% for the remaining species that suffered during the historical drought. In Aleppo pine, the plant attributes related to early field performance (growth in the first growing season) were more important in the drought-mediated mid-term performance than stock quality at the nursery stage. Within the technical framework of this study, our results allow for both testing and refining the regional quality standard specifications for harsh conditions such as those found in our study.This study is part of research projects: "Comprehensive quality control of the reforestation works in the public forest of Cortes de Pallas, Valencia" signed between UPV-ReForeST and the state-owned company TRAGSA, and "Monitoring and evaluation of the reforestation in the forest V-143 Muela de Cortes, in the municipality of Cortes de Pallas (Valencia), 10 years after its execution" (contract number CNMY18/0301/26), signed between UPV-ReForeST and Valencia Regional Government (CMAAUV, Generalitat Valenciana).Campo García, ADD.; Segura-Orenga, G.; Molina, AJ.; González-Sanchis, M.; Reyna, S.; Hermoso, J.; Ceacero, CJ. (2022). On the Need to Further Refine Stock Quality Specifications to Improve Reforestation under Climatic Extremes. Forests. 13(2):1-20. https://doi.org/10.3390/f1302016812013