19,676 research outputs found

    Influence of Embankments with Parapets on the Cross-Wind Turbulence Intensity at the Contact Wire of Railway Overheads

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    Winds as an environmental factor can cause significant difficulties for the railway system operation. The railway overhead has been particularly vulnerable to cross-winds related problems, such as development of undamped oscillations due to galloping phenomenon. The installation of windbreaks to decrease the aerodynamic loads on the train can affect the loads on railway overheads triggering cable galloping. One essential parameter to indicate the influence of the parapet wake on the catenary contact wire is the turbulence intensity. In this paper the results of an experimental analysis of the turbulence intensity due to the presence of parapets carried out in a wind tunnel are reported. Embankments equipped with different parapets have been tested and turbulence intensity has been measured at both contact wire locations, windward and leeward. The relative influence of the parapets is measured through a reduced turbulence intensity, defined as the ratio between the turbulence intensity measured with parapet and the turbulence intensity in the case without any parapet on the embankment. In general the reduced turbulence intensity increases as the height of the parapet increases

    The Telephonic Work of Spanish Pioneer Electrician Enrique Bonnet

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    The authors summarize the results of their research to bring to light and put into an international context the activities of this little-known, Cádiz-based inventor and entrepreneur who seems to have built Bell-type telephones as early as 1876, introducing his own commercial version in January 1878. In June 1878 he also had Hughes-type microphones for sale, and one year later he had combined them with his telephones in a set that included all the necessary elements to make and receive calls. Details of these instruments are given, taken from the descriptions written by Bonnet himself in an 1882 patent, and by one of his superiors in the State Telegraphs in a book published in 1884. Some considerations on the diffusion of his apparatus are also included

    Neutrino Energy Reconstruction and the Shape of the CCQE-like Total Cross Section

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    We show that because of the multinucleon mechanism effects, the algorithm used to reconstruct the neutrino energy is not adequate when dealing with quasielastic-like events, and a distortion of the total flux unfolded cross section shape is produced. This amounts to a redistribution of strength from high to low energies, which gives rise to a sizable excess (deficit) of low (high) energy neutrinos. This distortion of the shape leads to a good description of the MiniBooNE unfolded CCQE-like cross sections published in Phys.Rev. D81 (2010) 092005. However, these changes in the shape are artifacts of the unfolding process that ignores multinucleon mechanisms.Comment: 11 pages, 6 figures. Some references and comments adde

    The Public Institutiones Of Higher Education: Analysis Of The Factors That Affects The Educational System

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    En la presente investigación se retoma la teoría de la motivación humana que propone jerarquías de las necesidades, puesto que los seres humanos son motivados por necesidades múltiples y que solo existen en un orden jerárquico. Sin embargo, en las instituciones Públicas de Educación Superior en México, no hay resultados contundentes de la aplicación de esta teoría, ya que las áreas de oportunidad en el factor de motivación refleja que el personal que labora en estas instituciones no es se siente motivado por el trabajo que desempeña. Se analizaron siete instituciones de educación superior donde se encuestaron 224 sujetos divididos en directivo, mandos medios y personal operativo, en los subsistemas de educación Tecnológicas, Autónomas, Politécnicas, Tecnológicos de Estudios Superiores e Institutos Tecnológicos Superiores, en los estados de México, Puebla e Hidalgo. Considerando los factores de comunicación, motivación, satisfacción laboral, identidad, trabajo en equipo y liderazgo. Se logró comprobar la hipótesis estadística planteada, para lo cual se analizaron los factores de comunicación, motivación, satisfacción laboral, identidad, trabajo en equipo y liderazgo en los directivos, mandos medios y personal operativo. A partir de lo anterior, se acepta la hipótesis alternativa, es decir, que existe correlación significativa entre todas las variables estudiadas y se puede afirmar que son generalizables para toda la población.The purpose of the present research is to study the effects of statistical data on the behavior of Higher Education Faculties (IPES) in some states of the Mexican Republic. According to the ANUIES (2012) data base, in Hidalgo State 17% of students concluded their career, while 10.7% is graduated, this is associated that some students delay the academic process. In Mexico State 14.4% students complete the higher studies, but only 74.25% obtain their professional grade. Puebla indicates that 18% finished their studies and only 76% are graduated. Therefore, the most outstanding problems in higher education are the following situations: • Inequity in access to the detriment of young people from low economic status. • Limited relations with industrial-productive areas. • Discrepancy with other educational levels. • Insufficient economical support for research in public Universities and restricted relationship with the science and technology system. • Weak relevance and quality. • Growth of student population in higher institutions. Finally, the problematic considers that IPES has influences in the commitment of human resource to improve the results of the academic institutions, since in the higher education is one of the main factors in the educational process. Within the functional areas of the IPES, the main component to be studied is the academic employees, who provide the institution with knowledge, skills, abilities and capacities, which become human resource advantages; In return for this, the employees obtain benefits of salary, rewards, gratuities and promotions, therefore the degree of satisfaction increases its disposition when maintaining lines of activity with the educational organization. In this relationship of economic-social interchange the norm of reciprocity and variables such as communication, motivation, job satisfaction, identity, teamwork and leadership, so the degree of employee satisfaction generates a sense of belonging that favors the achievement of organizational objectives

    Flipped Classroom, an experience of open and flexible learning

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    El trabajo que presentamos muestra parte de un Proyecto desarrollado por el Grupo de Investigación InnoEduca de la Universidad de Málaga, que pretende conocer más acerca una metodología transformadora como es la clase invertida, buscando igualmente dar a conocer la flipped classroom como estrategia metodológica. La clase invertida consiste fundamentalmente en utilizar el tiempo fuera del aula en realizar ciertos procesos de enseñanza-aprendizaje que se han desarrollado dentro de la misma generalmente, en el aula el tiempo se emplea fundamentalmente en potenciar y facilitar otros procesos de adquisición y práctica de conocimientos. Entre los resultados obtenidos destacar la predisposición del alumnado para trabajar con metodologías innovadoras en las que asumen un papel más activo en los procesos de enseñanza-aprendizaje es positiva, a pesar de lo cual no se han observado cambios importantes en los hábitos de estudio. En estos momentos en los que las instituciones educativas pretenden mejorar las experiencias de aprendizaje y captar la atención de los estudiantes, las posibilidades que presenta el aula invertida hacen de esta un valor a tener en cuenta.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Groundwater pollution in quaternary aquifer of Vitoria - Gasteiz (Basque Country, Spain)

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    As a result of diverse changes in land use and in water-resource management in the high basin of the Zadorra River (Basque Country), an important loss of water resources and an intense contamination by nitrogen compounds has taken place. The purpose of this paper is to detail the land transformations that have taken place on the aquifer since the 1950s: increase of drainage network, change from dry to irrigated farming, and diversion of rivers at the aquifer unit inlet. Furthermore, we analyze the impact of these transformations on the hydrodynamics and water quality of this aquifer system
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