14,985 research outputs found

    A note on representation of references

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    We consider a class of relations which includes irreflexive preference relations and interdependent preferences. For this class, we obtain necessary and sufficient conditions for representation of the relation by two numerical functions in the sense of a < x if and only if u(a) < v(x)

    Micro-Jet Test Facility for Aerospace Propulsion Engineering Education

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    This paper describes the methodology that has been developed and implemented at the School ofAeronautics (ETSIA) of the Universidad Politecnica de Madrid (UPM) to familiarize aerospaceengineering students with the operation of real complex jet engine systems. This methodology has atwo-pronged approach: students carry out preparatory work by using, first, a gas turbineperformance prediction numerical code; then they validate their assumptions and results on anexperimental test rig. When looking at the educational aspects, we have taken care that, apart frombeing sufficiently robust and flexible, the experimental set-up is similar to real jet engine rigs, so thestudents are not constrained to exploring a much too limited parametric space. Also, because afacility like this is usually subject to extensive and somewhat rugged use, we have focused on a lowcost design

    The Pacific Alliance and the potential effects of a Trans-Pacific Economic Cooperation Agreement without the United States

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    This article analyzes the possible consequences of the entry into force of the Trans-Pacific Partnership Agreement (TPP) without the United States for the countries of the Pacific Alliance (PA). It develops a descriptive analysis of the evolution of trade between PA countries and TPP member countries during the period 1980-2015. Gravitational models are also estimated to empirically examine the determinants of trade flows in these countries. As a result, the paper shows that TPP may favor trade flows in PA countries, and that the withdrawal of the U.S. from TPP would not affect these trade flows.Este artículo analiza las posibles consecuencias, para los países de la Alianza del Pacífico (AP), de la entrada en vigor del Acuerdo de Asociación Transpacífico (TPP) sin Estados Unidos. Para ello, se desarrolla un análisis descriptivo de la evolución del comercio de los países de la AP con el resto de los países miembro del TPP durante el periodo 1980-2015. También se estiman modelos gravitacionales para examinar empíricamente los determinantes de los flujos comerciales de estos países. Se encuentra que el TPP puede favorecer los flujos comerciales de los países de la AP y que la salida de Estados Unidos del TPP no afectaría estos flujos comerciales

    “Zombie attack” a new way to teach Chemistry

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    The Higher Education requires new models which allow training people able to adapt and survive in changing environments. It is based on the use of technologies and the adaptation of knowledge to people. It is about an education according to circumstances, which is adapted to context and virtual behaviour of people. One of the main difficulties that lecturers find in the classroom is how to maintain students' attention and interest in their subject, especially when students also think that the subject is not important for their training. In order to motivate these students, innovation in educational techniques and methodologies, such as experiential learning, are progressively being imposed to and/or coordinated with the traditional ones. Escape Room is a very modern concept in education, based on the development of mental skills for the solution of enigmas and problems. It is a tool to develop the cooperative, cognitive, deductive and logical reasoning skills of the students. In this work, an educational gamification experience based on the escape room concept is presented. The students have 1 hour and 30 minutes to carry out this activity. They will have to solve four puzzles and enigmas that will give them the key to open a treasure chest and finally let them escape from the classroom. Logic, ingenuity and teamwork will allow participants to develop not only chemical competence, but also other basic skills. The story that is told throughout the escape room is a zombie attack: the city has been infected (with a virus) and only the occupants of the room where the activity takes place have not been infected. In addition, they can all protect themselves if they are able to open the chest where the antidote is located. The aim of this activity is to enhance the knowledge acquired throughout the semester as well as the development of skills.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    Morpho-kinematic analysis of the point-symmetric, bipolar planetary nebulae Hb 5 and K 3-17, a pathway to poly-polarity

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    The kinematics of the bipolar planetary nebulae Hb~5 and K 3-17 are investigated in detail by means of a comprehensive set of spatially resolved high spectral resolution, long-slit spectra. Both objects share particularly interesting characteristics, such as a complex filamentary, rosette-type nucleus, axial point-symmetry and very fast bipolar outflows. The kinematic information of Hb~5 is combined with {\it HST} imagery to construct a detailed 3D model of the nebula using the code SHAPE. The model shows that the large scale lobes are growing in a non-homologous way. The filamentary loops in the core are proven to actually be secondary lobes emerging from what appears to be a randomly punctured, dense, gaseous core and the material that forms the point symmetric structure flows within the lobes with a distinct kinematic pattern and its interaction with the lobes has had a shaping effect on them. Hb~5 and K~3-17 may represent a class of fast evolving planetary nebulae that will develop poly-polar characteristics once the nebular core evolves and expands.Comment: 19 pages, 8 figures. To appear in The Astrophysical Journa

    A note on representation of references.

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    We consider a class of relations which includes irreflexive preference relations and interdependent preferences. For this class, we obtain necessary and sufficient conditions for representation of the relation by two numerical functions in the sense of aPreference; Continuous representation; Pseudotransitivity; Biorders;

    Influence on yield and fruit quality of commercial rootstocks of pepper (Capsicum annuum L.)

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    El cultivo del pimiento en Almería es muy importante; se producen 7000 ha en la provincia. La importancia de este cultivo hace que se hayan adoptado nuevas técnicas para incrementar la producción, tales como el fertirriego, el entutorado y el manejo integrado de plagas. Sin embargo el uso de plantas injertadas aun no está bien implementado en la región, debido a la falta de patrones comerciales que sean del todo satisfactorios. Por esta razón se planteó evaluar el uso de patrones comerciales de pimiento. El experimento constó de cuatro tratamientos con tres repeticiones, tres de los tratamientos fueron plantas injertadas de pimiento variedad Urano sobre los patrones Atlante, AR40 y Tresor, a una densidad de 1,6 plantas/m2, como testigo el cultivar Urano a una densidad de 2,3 plantas/m2. Se midieron parámetros de producción y calidad. En producción, los pimientos injertados sobre los patrones Atlante y AR40 no mostraron diferencias significativas con respecto al Testigo. En los parámetros de calidad tampoco hubo diferencias significativas entre los frutos procedentes de planta injertada con respecto al Testigo. El tratamiento donde se utilizó el patrón Tresor fue el menos productivo con diferencias significativas, sin embargo fue el que produjo frutos de mayor peso y con más grosor de pared. Los resultados indican que el uso de ciertos patrones incrementa el rendimiento por planta en el cultivo del pimiento a la vez que pueden modificar algunas características del fruto
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