3,621 research outputs found

    Remarks on twisted theories with matter

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    We investigate some aspects of N=2 twisted theories with matter hypermultiplets in the fundamental representation of the gauge group. A consistent formulation of these theories on a general four-manifold requires turning on a particular magnetic flux, which we write down explicitly in the case of SU(2k). We obtain the blowup formula and show that the blowup function is given by a hyperelliptic sigma-function with singular characteristic. We compute the contact terms and find, as a corollary, interesting identities between hyperelliptic Theta functions.Comment: 18 pages, harvmac, one figur

    Design of an Efficient Interconnection Network of Temperature Sensors

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    Temperature has become a first class design constraint because high temperatures adversely affect circuit reliability, static power and degrade the performance. In this scenario, thermal characterization of ICs and on-chip temperature monitoring represent fundamental tasks in electronic design. In this work, we analyze the features that an interconnection network of temperature sensors must fulfill. Departing from the network topology, we continue with the proposal of a very light-weight network architecture based on digitalization resource sharing. Our proposal supposes a 16% improvement in area and power consumption compared to traditional approache

    UrOAC: Urban Objects in Any-light Conditions

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    In the past years, several works on urban object detection from the point of view of a person have been made. These works are intended to provide an enhanced understanding of the environ- ment for blind and visually challenged people. The mentioned approaches mostly rely in deep learning and machine learning methods. Nonetheless, these approaches only work with direct and bright light, namely, they will only perform correctly on daylight conditions. This is because deep learning algorithms require large amounts of data and the currently available datasets do not address this matter. In this work, we propose UrOAC, a dataset of urban objects captured in a range of different lightning conditions, from bright daylight to low and poor night-time lighting conditions. In the latter, the objects are only lit by low ambient light, street lamps and headlights of passing-by vehicles. The dataset depicts the following objects: pedestrian crosswalks, green traffic lights and red traffic lights. The annotations include the category and the bounding-box of each object. This dataset could be used for improve the performance at night-time and under low-light conditions of any vision-based method that involves urban objects. For instance, guidance and object detection devices for the visually challenged or self-driving and intelligent vehicles.This work has been supported by the Spanish Government PID2019-104818RB-I00 Grant, co-funded by EU Structural Funds

    Common visual preference for curved contours in humans and great apes

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    This study was funded by research grants FFI2010-20759 and FFI2013-43270-P from the Spanish Government Ministerio de Economía y Competitividad. Gerardo Gomez-Puerto was supported by the grant BES-2011-047441.Among the visual preferences that guide many everyday activities and decisions, from consumer choices to social judgment, preference for curved over sharp-angled contours is commonly thought to have played an adaptive role throughout human evolution, favoring the avoidance of potentially harmful objects. However, because nonhuman primates also exhibit preferences for certain visual qualities, it is conceivable that humans' preference for curved contours is grounded on perceptual and cognitive mechanisms shared with extant nonhuman primate species. Here we aimed to determine whether nonhuman great apes and humans share a visual preference for curved over sharp-angled contours using a 2-alternative forced choice experimental paradigm under comparable conditions. Our results revealed that the human group and the great ape group indeed share a common preference for curved over sharp-angled contours, but that they differ in the manner and magnitude with which this preference is expressed behaviorally. These results suggest that humans' visual preference for curved objects evolved from earlier primate species' visual preferences, and that during this process it became stronger, but also more susceptible to the influence of higher cognitive processes and preference for other visual features.Publisher PDFPeer reviewe

    Análisis Preliminar de la Influencia del Proceso de Torneado en la vida a fatiga de la Aleación de Aluminio UNS A92024-T351

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    Generalmente los elementos estructurales metálicos de las aeronaves se ubican en zonas de carga crítica, en la mayoría de los casos, estos elementos son conformados mediante procesos de mecanizado. La vida a fatiga de estos componentes es una propiedad dinámica muy importante que puede verse intensamente afectada por las condiciones superficiales producidas durante el proceso de mecanizado. En este trabajo se lleva a cabo un primer estudio de la influencia de los parámetros de corte en la resistencia a la fatiga de piezas torneadas de la aleación de aluminio aeronáutico UNS A92024-T351. Se ha prestado especial atención a la relación con el acabado superficial evaluado a partir de la rugosidad media aritmétic

    An analysis of geographical concentration of productivity: the case of manufacture firms in the Ebro Valley

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    En este trabajo se analiza la concentración espacial de las empresas de manufacturas ubicadas en el Valle del Ebro, atendiendo a sus niveles de productividad. El periodo que utilizamos es 1996 a 2009. Los resultados obtenidos nos permiten valorar el impacto del entorno socioeconómico y geográfico del Valle del Ebro en la tendencia a la concentración de la productividad, lo que se conoce como externalidades espaciales. Estos resultados muestran una fuerte correlación entre tamaño del municipio, densidad y productividad. A nivel provincial, destacan las concentraciones de alta productividad en Barcelona, La Rioja, Girona y Navarra. Otros factores que ejercen un efecto positivo sobre la concentración de la productividad son: i) el atractivo del emplazamiento con preferencia por la litoralidad; ii) la cercanía a infraestructuras de comunicaciones como la autopista A2; iii) la diversidad de empresas entendida como existencia, en el entorno de una empresa, de otras empresas de sectores complementarios. Entre los aspectos que influyen negativamente sobre los datos de productividad destacan las dificultades de comunicación con el exterior, la falta de presión demográfica y la desventaja tecnológica.In this work we analyse the spatial concentration of manufacture firms in the Ebro Valley, in relation to their productivity level. We use data for the period 1996 to 2009. The results allow to evaluate the impact of socio-economic and geographic aspects of the Ebro Valley on productivity concentration, known as spatial externalities. Results show a positive strong correlation among size of municipality, density and productivity. Among provinces, it is remarkable the high concentration of productivity in Barcelona, La Rioja, Girona and Navarra. Other factors with a positive effect on productivity concentration are the following: i) the environment attractiveness, with a strong preference for the coast; ii) the accessibility to communication infrastructures such as the A2 highway; iii) diversity, understood as the existence, in the proximity, of other firms belonging to different and complementary activity sectors. Factors that negatively affect the concentration of productivity are accessibility difficulties, low demographic pressure and technological disadvantages.Fil: Angulo, Ana M.. Universidad de Zaragoza; España;Fil: Herrera Gomez, Marcos Hernan. Universidad Nacional de Salta. Facultad de Ciencias Económicas, Jurídicas y Sociales. Instituto de Estudios Laborales y del Desarrollo Económico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta; ArgentinaFil: Atwi , Majed. Universidad de Zaragoza; España

    On the relation of negations in Nelson algebras

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    The aim of this paper is to investigate the relation between the strong and the “weak” or intuitionistic negation in Nelson algebras. To do this, we define the variety of Kleene algebras with intuitionistic negation and explore the Kalman’s construction for pseudocomplemented distributive lattices. We also study the centered algebras of this variety.Fil: Gomez, Conrado Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Matemática Aplicada del Litoral. Universidad Nacional del Litoral. Instituto de Matemática Aplicada del Litoral; ArgentinaFil: Marcos, Miguel. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: San Martín, Hernán Javier. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
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