53,723 research outputs found

    Fusing Audio, Textual and Visual Features for Sentiment Analysis of News Videos

    Full text link
    This paper presents a novel approach to perform sentiment analysis of news videos, based on the fusion of audio, textual and visual clues extracted from their contents. The proposed approach aims at contributing to the semiodiscoursive study regarding the construction of the ethos (identity) of this media universe, which has become a central part of the modern-day lives of millions of people. To achieve this goal, we apply state-of-the-art computational methods for (1) automatic emotion recognition from facial expressions, (2) extraction of modulations in the participants' speeches and (3) sentiment analysis from the closed caption associated to the videos of interest. More specifically, we compute features, such as, visual intensities of recognized emotions, field sizes of participants, voicing probability, sound loudness, speech fundamental frequencies and the sentiment scores (polarities) from text sentences in the closed caption. Experimental results with a dataset containing 520 annotated news videos from three Brazilian and one American popular TV newscasts show that our approach achieves an accuracy of up to 84% in the sentiments (tension levels) classification task, thus demonstrating its high potential to be used by media analysts in several applications, especially, in the journalistic domain.Comment: 5 pages, 1 figure, International AAAI Conference on Web and Social Medi

    Passiv damping on spacecraft sandwich panels

    Get PDF
    For reusable and expendable launch vehicles as well as for other spacecraft structural vibration loads are safety critical design drivers impacting mass and lifetime. Here, the improvement of reliability and safety, the reduction of mass, the extension of service life, as well as the reduction of cost for manufacturing are desired. Spacecraft structural design in general is a compromise between lightweight design and robustness with regard to dynamic loads. The structural stresses and strains due to displacements caused by dynamic loads can be reduced by mechanical damping based on passive or active measures. Passive damping systems can be relatively simple and yet are capable of suppressing a wide range of mechanical vibrations. Concepts are low priced in development, manufacturing and application as well as maintenancefree. Compared to active damping measures passive elements do not require electronics, control algorithms, power, actuators, sensors as well as complex maintenance. Moreover, a reliable application of active dampers for higher temperatures and short response times (e. g. re-entry environment) is questionable. The physical effect of passive dampers is based on the dissipation of load induced energy. Recent activities performed by OHB have shown the function of a passive friction-damping device for a vertical tail model of the German X-vehicle PHÖNIX but also for general sandwich structures. The present paper shows brand new results from a corresponding ESA-funded activity where passive damping elements are placed between the face sheets of large spacecraft relevant composite sandwich panels to demonstrate dynamic load reduction in vibration experiments on a shaker. Several passive damping measures are investigated and compared

    Time-scale analysis non-local diffusion systems, applied to disease models

    Full text link
    The objective of the present paper is to use the well known Ross-Macdonald models as a prototype, incorporating spatial movements, identifying different times scales and proving a singular perturbation result using a system of local and non-local diffusion. This results can be applied to the prototype model, where the vector has a fast dynamics, local in space, and the host has a slow dynamics, non-local in space

    Semilinear elliptic equations in thin regions with terms concentrating on oscillatory boundaries

    Get PDF
    In this work we study the behavior of a family of solutions of a semilinear elliptic equation, with homogeneous Neumann boundary condition, posed in a two-dimensional oscillating thin region with reaction terms concentrated in a neighborhood of the oscillatory boundary. Our main result is concerned with the upper and lower semicontinuity of the set of solutions. We show that the solutions of our perturbed equation can be approximated with ones of a one-dimensional equation, which also captures the effects of all relevant physical processes that take place in the original problem

    Detection of new eruptions in the Magellanic Clouds LBVs R 40 and R 110

    Full text link
    We performed a spectroscopic and photometric analysis to study new eruptions in two luminous blue variables (LBVs) in the Magellanic Clouds. We detected a strong new eruption in the LBV R40 that reached V∼9.2V \sim 9.2 in 2016, which is around 1.31.3 mag brighter than the minimum registered in 1985. During this new eruption, the star changed from an A-type to a late F-type spectrum. Based on photometric and spectroscopic empirical calibrations and synthetic spectral modeling, we determine that R\,40 reached Teff=5800−6300T_{\mathrm{eff}} = 5800-6300~K during this new eruption. This object is thereby probably one of the coolest identified LBVs. We could also identify an enrichment of nitrogen and r- and s-process elements. We detected a weak eruption in the LBV R 110 with a maximum of V∼9.9V \sim 9.9 mag in 2011, that is, around 1.01.0 mag brighter than in the quiescent phase. On the other hand, this new eruption is about 0.20.2 mag fainter than the first eruption detected in 1990, but the temperature did not decrease below 8500 K. Spitzer spectra show indications of cool dust in the circumstellar environment of both stars, but no hot or warm dust was present, except by the probable presence of PAHs in R\,110. We also discuss a possible post-red supergiant nature for both stars
    • …
    corecore