57,548 research outputs found

    The European Union and the United States, before the election: a much deeper mutual understanding. Jean Monnet/Robert Schuman Paper Series Vol. 12 Special, October 2012

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    From the Introduction. Governor Romney’s statement that President Obama was trying to convert the United States into a European state actually served to point out the need for a much deeper understanding of both entities to make considerable progress in the future. The need for a close alliance is taken for granted. However, the link is riddled with confusion and stereotypes. This relationship is considered a normal fact forged by mutual historical legacies. Hence the frequent signs of awkward behaviour and misunderstandings under the cover of the notion that potential damage will be corrected by the force of the special relationship. If conflicts are detected, both parties are said to be condemned to agree. If a lack of knowledge is detected, it will be modified by accessible means. Mechanisms for an understanding and cooperation are within reach. Therefore, an effective relationship is not utopian. However, there are areas in which much work is needed to strengthen the alliance and correct its shortcomings. There is a need, not only for agreements in economic and political issues, but also for a deeper understanding of the essence of both entities

    Categorical Comprehensions and Recursion

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    A new categorical setting is defined in order to characterize the subrecursive classes belonging to complexity hierarchies. This is achieved by means of coercion functors over a symmetric monoidal category endowed with certain recursion schemes that imitate the bounded recursion scheme. This gives a categorical counterpart of generalized safe composition and safe recursion.Comment: Comments are welcom

    Precision of cavity-enhanced optical rotation measurements

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    The signal to noise ratio in atomic magnetometry is fundamentally limited by the optical depth of the atomic ensemble. During the last decade, different technics for optical depth enhancement has been developed by several groups, some of them involving the implementation of an optical cavity. This thesis evaluates the performance of such an implementation by the polarization read out noise analysis of an optical cavity with similar characteristics as the already implemented by other groups. We obtained an estimated value for the signal to noise ratio enhancement with a cavity of 814 Finesse, and we studied the behaviour of the different sources of polarization noise in this system

    Domestic oven heated by a concentrating solar collector

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    A project to power a domestic oven by solar energy was developed. The focal axis of a cylindrical parabolic reflector usually reaches temperatures of up to 250ºC. A heat transfer fluid carries this heat to the heat exchanger in the oven. Current domestic ovens are generally electric and can reach 250ºC with a power of 2-3 kW. The installation is composed of pumps, valves, thermally insulated pipes, exchanger, etc. These elements transfer the heat collected by the solar collector to the oven in the house. If the installation has an accumulator tank with thermal insulation, the high temperature liquid makes it possible to use the oven at any time. Unlike current domestic solar ovens, this technology can reach the same temperature and power as an electric oven, and be used indoors at any time. Additionally, this system could be used for sanitary hot water purposes and radiating floors. In these cases, the high temperature is degraded mixing with cold water.Postprint (published version

    Adolescents from low-income sectors: the challenge of studying in a time of digital environments

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    This paper is about practices and perceptions regarding the study of adolescents from low-income sectors in the City of Buenos Aires. The methodology consisted of 26 in-depth interviews with low-income adolescents and participant observations in twenty cybercafés of the South Area of the City of Buenos Aires. Among the findings, these students highlight that ICTs allow them to handle information in a more agile and entertaining way, more consistent with their daily uses. However, doing research on school content is what students do the least, since adolescents use technology mainly for communicative, social and recreational ends. These adolescents recognise some disadvantages in using ICTs to study: the unreliable information, the difficulty to distinguish which topics related to school content are more appropriate and the disruptive and continuous use of social networks. In this sense, these adolescents tend to have more problems in benefitting from ICTs for academic purposes than other adolescents. While communication and recreational skills tend to be similar, the evaluation of different sources of information and the skill to make complex searches online are usually more strongly developed in adolescents of middle and high-income households. In conclusion, we think it is necessary to take these problems into consideration in the social sciences research of the area and besides when implementing digital literacy programs.Fil: Linne, Joaquín Walter. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigaciones ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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