33,619 research outputs found

    Social innovation practices: focus on success factors for crowdfunding

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    This article explores what are the success factor for interaction with platforms of crowdfunding in Italy. Through a Principal Component Analysis we outline three variables and through a multiple regression analysis we demonstrate that the interaction on crowdfunding is positive correlated with socio-economic propensity and cultural level. The analysis has been conducted on a sample of 316 of projects funded in the Crowdfunding platform Produzioni dal Basso, the first platform born in Italy. We draw on SD logic and relationship marketing to underscore the importance of networks of actors and integration to create a co-creation of value. This view emphasizes the social and economic factors that influence, and are influenced by, crowdfundin

    A 300 GHz "Always-in-Focus" Focusing System for Target Detection

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    A focusing system for a 300 GHz radar with 5 m target distance and 10 mm diameter spot size resolution is proposed. The focusing system is based on a Gaussian telescope scheme and its main parameters have been de¬signed using Gaussian beam quasi-optical propagation theory with an in-house developed MATLAB® based analysis tool. Then, this approach has been applied to a real focusing system based on two elliptical mirrors in order to reduce the distortion and cross-polar level and a plane mirror to provide scanning capabilities. The over¬all system has been simulated with a full-wave electromag¬netic simulator and its behavior is presented. With this approach, the focusing system always works "in-focus" since the only mirror that is rotated when scanning is the output plane mirror, so the beam is almost not distorted. The design process, although based in the well-known Gaussian beam quasi-optical propagation theory, provides a fast and accurate method and minimizes the overall size of the mirrors. As a consequence, the size of the focusing system is also reduced

    Feature extraction of the wear label of carpets by using a novel 3D scanner

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    In the textile industry, the quality of carpets is still determined through visual assessment by human experts. Human assessment is somewhat subjective, so there is a need for a more objective assessment which yields to automated systems. However, existing computer models are at this moment not yet capable of matching the human expertise. Most attempts at automated assessment have focused on image analysis of two dimensional images of worn carpet. These do not adequately capture the three dimensional structure of the carpet that is also evaluated by the experts and the image processing is very dependent on the lighting conditions. One previous attempt however used a laser scanner to obtain three dimensional images of the carpet and process them for carpet assessment. This paper describes the development of a new scanner to acquire wear label characteristics in three dimensions based on a structured light pattern. Now an appropriate technique based on the local binary patterns (LBP) and the Kullback-Leibler divergence has been developed. We show that the new laser scanning system is less dependent on the lighting conditions and color of the carpet and obtains data points on a structured grid instead of sparse points. The new system is also more than five times cheaper, scans more than seven times faster and is specifically designed for scanning carpets instead of 3D objects. Previous attempts to classify the carpet wear were based on several extracted features. Only one of them - the height difference between worn and unworn part - showed a good correlation of 0.70 with the carpet wear label. However, experiments demonstrate that our approach - using the LBP technique - gives rise to promising results, with correlation factors from 0.89 to 0.99 between the Kullback-Leibler divergence and quality labels. This new laser scanner system is a significant step forward in the automated assessment of carpet wear using 3D images

    Beyond divide and rule: weak dictators, natural resources and civil conflict

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    We propose a model where an autocrat rules over an ethnically divided society. The dictator selects the tax rate over domestic production and the nation's natural resources to maximize his rents under the threat of a regime-switching revolution. We show that a weak ruler may let the country plunge in civil war to increase his personal rents. Inter-group fighting weakens potential opposition to the ruler, thereby allowing him to increase fiscal pressure. We show that the presence of natural resources exacerbatesthe incentives of the ruler to promote civil conflict for his own profit, especially if the resources are unequally distributed across ethnic groups. We validate the main predictions of the model using cross-country data over the period 1960-2007, and show that our empirical results are not likely to be driven by omitted observable determinants of civil war incidence or by unobservable country-specific heterogeneity.

    Analysing wear in carpets by detecting varying local binary patterns

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    Currently, carpet companies assess the quality of their products based on their appearance retention capabilities. For this, carpet samples with different degrees of wear after a traffic exposure simulation process are rated with wear labels by human experts. Experts compare changes in appearance in the worn samples to samples with original appearance. This process is subjective and humans can make mistakes up to 10% in rating. In search of an objective assessment, research using texture analysis has been conducted to automate the process. Particularly, Local Binary Pattern (LBP) technique combined with a Symmetric adaptation of the Kullback-Leibler divergence (SKL) are successful for extracting texture features related to the wear labels either from intensity and range images. We present in this paper a novel extension of the LBP techniques that improves the representation of the distinct wear labels. The technique consists in detecting those patters that monotonically change with the wear labels while grouping the others. Computing the SKL from these patters considerably increases the discrimination between the consecutive groups even for carpet types where other LBP variations fail. We present results for carpet types representing 72% of the existing references for the EN1471:1996 European standard

    Analyzing {\gamma}-rays of the Galactic Center with Deep Learning

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    We present a new method to interpret the γ\gamma-ray data of our inner Galaxy as measured by the Fermi Large Area Telescope (Fermi LAT). We train and test convolutional neural networks with simulated Fermi-LAT images based on models tuned to real data. We use this method to investigate the origin of an excess emission of GeV γ\gamma-rays seen in previous studies. Interpretations of this excess include γ\gamma rays created by the annihilation of dark matter particles and γ\gamma rays originating from a collection of unresolved point sources, such as millisecond pulsars. Our new method allows precise measurements of the contribution and properties of an unresolved population of γ\gamma-ray point sources in the interstellar diffuse emission model.Comment: 24 pages, 11 figure

    Versión reducida de la escala de actitudes frente al alcohol, alcoholismo y al alcohólico: resultados preliminares

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    Este estudo teve como objetivo analisar os itens da Escala de Atitudes frente ao Álcool, ao Alcoolismo e ao Alcoolista, a fim de elaborar uma versão reduzida, mantendo as propriedades psicométricas do instrumento. Em sua versão preliminar, a escala foi constituída por 165 itens, sendo aplicada a uma amostra de 144 estudantes de enfermagem. O processo de avaliação dos itens deu-se pela análise da correlação do item total e a confiabilidade do instrumento foi estimada pelo coeficiente alfa de Crombach. Os resultados obtidos indicaram a permanência de 83 itens, divididos em cinco fatores que apresentaram valores satisfatórios nos diferentes coeficientes de consistência interna. Concluiu-se que o resultado do estudo abre perspectivas para novas pesquisas, com a necessidade de ampliação da amostra com vistas a dar continuidade ao processo de validação da Escala de Atitudes frente ao Álcool, ao Alcoolismo e ao Alcoolista entre profissionais da saúde.This study aimed to analyze the items of the Scale of Attitudes toward Alcohol, alcoholism and alcoholics in order to prepare a reduced version keeping the instrument's psychometric properties. The preliminary version of the Scale composed by 165 items was tested in a sample with 144 nursing student. The evaluation process of the items consisted of the total-item coefficient correlation and reliability of the instrument was estimated by Cronbach's alpha coefficient. Results indicate the permanence of 83 items, divided into five factors that showed satisfactory values in the different coefficients of internal consistency. Further studies are needed with larger samples in order to give continuity to the process of scale validation among health professionals.Este estudio objetivó analizar los ítems de la Escala de Actitudes frente al Alcohol, al Alcoholismo y al Alcohólico, a fin de elaborar una versión reducida manteniendo las propiedades psicométricas del instrumento. En su versión preliminar, la escala se constituyó de 165 ítems, aplicándose a muestra de 144 estudiantes de enfermería. El proceso de evaluación de ítems se realizó por análisis de correlación de ítem total; la confiabilidad del instrumento se estimó por coeficiente alfa de Crombach. Los resultados obtenidos indicaron la permanencia de 83 ítems, divididos en cinco factores que presentaron valores satisfactorios en los diferentes coeficientes de consistencia interna. Se concluyó en que el resultado del estudio abre perspectivas para nuevas investigaciones, con necesidad de ampliación de la muestra, a fin de dar continuidad al proceso de validación de Escala de Actitudes frente al Alcohol, al Alcoholismo y al Alcohólico entre profesionales de la salud

    Observing Grasping Actions Directed to Emotion-Laden Objects: Effects upon Corticospinal Excitability

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    The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE). Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs) were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS) while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1) maximum grip aperture, and (2) object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system.Fil: Nogueira Campos, Anaelli A.. Universidade Federal de Juiz de Fora; BrasilFil: Saunier, Ghislain. Universidade Federal do Pará; BrasilFil: Della Maggiore, Valeria Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: De Oliveira, Laura A. S.. Centro Universitário Augusto Motta; BrasilFil: Rodrigues, Erika C.. Centro Universitário Augusto Motta; BrasilFil: Vargas, Claudia D.. Universidade Federal do Rio de Janeiro; Brasi
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