8,599 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)

    Greek-latin mythology and rock. The myth of Prometheus in lyrics of Extremoduro, Tierra Santa and Kutxi Romero & Ja ta Ja

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    A pesar de la creencia de que las letras de la música rock española actual están llenas de mensajes vacíos y de tópicos repetidos, podemos encontrar grupos y solistas cuyas composiciones se alejan de ese cliché para servir de vehículo de transmisión de cuestiones culturales como pueda ser la mitología clásica. Además, esta transmisión no siempre se queda en la mera anécdota de la cita culturalista, sino que en ocasiones va más allá, haciendo que el mito sirva como elemento de comparación o, incluso, recreándolo. Las siguientes páginas pasarán revista a la aparición del mito de Prometeo en las letras de tres grupos de rock nacional contemporáneos: Extremoduro, Tierra Santa y la colaboración entre el cantante y letrista de Marea, Kutxi Romero, con Ja ta Ja.In spite of the belief that the lyrics of current Spanish rock music are full of empty messages and repeated topics, we can find groups and soloist whose compositions move away from that chiclé to serve as a transmission vehicle of cultural questions such as classical mythology. Besides, this transmission is not always just a mere anecdote of the culturalist quote, but on some occasions it goes further, making the myth an element of comparison, or even recreating it. The following pages will review the appearance of the Prometheus myth in the lyrics of three contemporary national rock groups: Extremoduro, Tierra Santa and the collaboration between the singer and composer of Marea, Kutxi Romero, with Ja ta Ja.peerReviewe

    Can ecosystem properties be fully translated into service values? an economic valuation of aquatic plant services

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    Ecological Applications 21. 5 (2011): 3083-3103 copyright by the Ecological Society of AmericaWe carried out an integrated analysis of ecosystem services in the Doñana social-ecological system (southwestern Spain), from the providers (different aquatic plant functional groups) to the beneficiaries (different stakeholders living in or visiting the area). We explored the ecosystem services supplied by aquatic plants by linking these services to different plant functional traits, identifying relevant ecosystem services and then working our way backward to ecosystem properties and the functional traits underpinning them. We started from 15 ecosystem services associated with aquatic systems (freshwater marshes, salt marshes, ponds on aeolian sheets, temporal coastal ponds, and estuaries) and related them to plant traits (directly or indirectly through intermediate ecosystem properties). We gathered information from the literature on the functional traits of 144 plants occurring in the aquatic ecosystems of Doñana. We analyzed the species×trait matrix with multivariate classification and ordination techniques and obtained seven functional groups with different potentials for delivering ecosystem services. A survey was then administered to 477 stakeholders to analyze, through the use of a contingent valuation exercise, how the ecosystem services provided by the different functional groups were valued. We identified connections between individual plant traits, ecosystem processes, and ecosystem services, but a mismatch appeared between the functional groups and the economic values placed on them by the beneficiaries. We found that contingent valuation applied to ecosystem services tended to ignore the ecosystem properties and biodiversity underpinning them. Our results cast doubts over the suitability of the economic valuation framework of ecosystem services to capture the full value of biodiversity and ecosystems to peopleThis research was partially supported by a grant from the Madrid Regional Government of Education, which was co-funded by the Social European Fund (F.S.E.), the Spanish Ministry of Education and Science (Project CGL2006- 14121/BOS), and the Spanish Ministry of the Environment and Rural and Marine Affairs through project 018/2009. S. Díaz acknowledges support from FONCyT and CONICET (Argentina) and IAI (CRN 2015, supported by US NSF GEO- 0452325

    Detection of inter-turn faults in multi-phase ferrite-PM assisted synchronous reluctance machine

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    Inter-turn winding faults in five-phase ferrite-permanent magnet-assisted synchronous reluctance motors (fPMa-SynRMs) can lead to catastrophic consequences if not detected in a timely manner, since they can quickly progress into more severe short-circuit faults, such as coil-to-coil, phase-to-ground or phase-to-phase faults. This paper analyzes the feasibility of detecting such harmful faults in their early stage, with only one short-circuited turn, since there is a lack of works related to this topic in multi-phase fPMa-SynRMs. Two methods are tested for this purpose, the analysis of the spectral content of the zero-sequence voltage component (ZSVC) and the analysis of the stator current spectra, also known as motor current signature analysis (MCSA), which is a well-known fault diagnosis method. This paper compares the performance and sensitivity of both methods under different operating conditions. It is proven that inter-turn faults can be detected in the early stage, with the ZSVC providing more sensitivity than the MCSA method. It is also proven that the working conditions have little effect on the sensitivity of both methods. To conclude, this paper proposes two inter-turn fault indicators and the threshold values to detect such faults in the early stage, which are calculated from the spectral information of the ZSVC and the line currentsPeer ReviewedPostprint (published version

    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;

    The long shadow of the digital framework. Dossier presentation: History of the new Digital Media

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    Desde la Comunicación nos interesa la complejidad abierta por el entramado digital en las sociedades porque solo así, en ese contexto en el que emergen renovadas formas de organización social y de prácticas sociales, podemos entender los flujos comunicativos en el nuevo mundo de la sociedad red. De ese escenario, nuestros objetos de estudio dirigen el foco, de forma preferente, a las tecnologías digitales en tanto que entraron en los medios electrónicos, analógicos primero y digitales más tarde. Lo que ocurre es que todavía el tiempo transcurrido del digitalismo suma pocos dígitos y la mirada interpretativa histórica, aunque es factible y ha posibilitado brillantes aportaciones, encuentra algunas limitaciones para un análisis fundamentado que abarque todas las dimensiones de los procesos que envuelven tal complejidad

    “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

    Valoración de las tablas 'input-output' interregionales de la economía española

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    En el presente artículo, y tras una primera presentación del proceso de elaboración de las tablas interregionales estimadas por el Instituto L. R. Klein, se aborda un análisis cuantitativo que trata de valorar los posibles sesgos derivados de la utilización de tablas interregionales, frente a las tablas unirregionales clásicas, así como las desviaciones entre los resultados que se obtendrían de estas tablas estimadas con procedimientos indirectos (non-survey) frente a las realizadas con procedimientos directos (survey). Los resultados iniciales parecen confirmar, tanto la eficacia de los métodos indirectos de estimación de tablas input-output interregionales, como la existencia de un cierto sesgo de agregación espacial

    Embedded optimization-based controllers for industrial processes

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    © 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Due to the growth of computational capabilities and the proliferation of field-programmable gate arrays (FPGA), the utilization of model predictive control (MPC) for embedded applications in the industry has become a possibility and a fact. This paper presents and discusses the possibilities of the use of online MPC, embedded in an educational device from National Instruments, using two different optimization algorithms and code generators, which have come out in recent years by the academia: CVXGEN, which implements a primal-dual interior-point algorithm, and qpOASES, which relies on the online active-set strategy algorithm. Both algorithms have been tested both in simulation and in real-time experimentation to control a four-tank pilot plant.Peer ReviewedPostprint (author's final draft
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