2,162 research outputs found

    Embrapa Technological Information: a bridge between research and society

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    This paper presents the efforts undertaken by the Brazilian Agricultural Research Corporation regarding Science and Technology information management, through one of its Decentralized Units, Embrapa Technological Information (Scientific and Technological Information Service', SCT). The major aim of SCT is to promote and improve the processes of scientific communication - information that feeds and that results from research activities - and of science and technology dissemination - information that results from research activities and that is directed to the general publi

    Multiscale Astronomical Image Processing Based on Nonlinear Partial Differential Equations

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    Astronomical applications of recent advances in the field of nonastronomical image processing are presented. These innovative methods, applied to multiscale astronomical images, increase signal-to-noise ratio, do not smear point sources or extended diffuse structures, and are thus a highly useful preliminary step for detection of different features including point sources, smoothing of clumpy data, and removal of contaminants from background maps. We show how the new methods, combined with other algorithms of image processing, unveil fine diffuse structures while at the same time enhance detection of localized objects, thus facilitating interactive morphology studies and paving the way for the automated recognition and classification of different features. We have also developed a new application framework for astronomical image processing that implements some recent advances made in computer vision and modern image processing, along with original algorithms based on nonlinear partial differential equations. The framework enables the user to easily set up and customize an image-processing pipeline interactively; it has various common and new visualization features and provides access to many astronomy data archives. Altogether, the results presented here demonstrate the first implementation of a novel synergistic approach based on integration of image processing, image visualization, and image quality assessment

    Enhancement of Historical Printed Document Images by Combining Total Variation Regularization and Non-Local Means Filtering

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    This paper proposes a novel method for document enhancement which combines two recent powerful noise-reduction steps. The first step is based on the total variation framework. It flattens background grey-levels and produces an intermediate image where background noise is considerably reduced. This image is used as a mask to produce an image with a cleaner background while keeping character details. The second step is applied to the cleaner image and consists of a filter based on non-local means: character edges are smoothed by searching for similar patch images in pixel neighborhoods. The document images to be enhanced are real historical printed documents from several periods which include several defects in their background and on character edges. These defects result from scanning, paper aging and bleed- through. The proposed method enhances document images by combining the total variation and the non-local means techniques in order to improve OCR recognition. The method is shown to be more powerful than when these techniques are used alone and than other enhancement methods

    PDE Based Enhancement of Color Images in RGB Space

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    International audienceA novel method for color image enhancement is proposed as an extension of scalar diffusion-shock filter coupling model, where noisy and blurred images are denoised and sharpened. The proposed model is based on using single vectors of the gradient magnitude and the second derivatives as a technique to relate different color components of the image. This model can be viewed as a generalization of Bettahar-Stambouli filter to multi-valued images. The proposed algorithm is more efficient than the mentioned filter and some previous works on color image denoising and deblurring without creating false colors

    Managing quality assurance and enhancement processes in higher education with special reference to initial teacher training provision

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    My intention in carrying out this project was to examine the relevance of developing refined approaches toward quality assurance in order to accommodate external demand under a common system. Each area of critical analysis established sources of conflict of interest amongst academics in the School and provided an indication of the way in which these might be resolved. The academic provision in the School is diverse and is subject to external scrutiny through the Quality Assurance Agency (QAA) and Teacher Training Agency (TTA) the latter of whom works alongside the Office for Standards in Teacher Education, OfSTED. Throughout this time the University has operated an internal quality assurance and enhancement process based on the QAA quality assurance methodology whereas Initial Teacher Training programmes within the School have been subject to the inspection methodology of OfSTED. Three areas of critical analysis formed the basis of my research methodology conducted through case study and primary document analysis. The self assessment document is a product of QAA demand and contrasts with OfSTED inspection demand, the subject specification raises questions about knowledge and its control in higher education when compared with the TTA Standards for the Award of Qualified Teacher Status, and the School Annual Monitoring Report represents the internal dichotomy of demand that sometimes exists for members of academic staff who engage in the process of writing such reports. My main finding suggests that the 'self imposed burden' of quality assurance can be reduced within the University and School in order to facilitate a more coherent and effective QA process

    A Mask-Based Enhancement Method for Historical Documents

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    This paper proposes a novel method for document enhancement. The method is based on the combination of two state-of-the-art filters through the construction of a mask. The mask is applied to a TV (Total Variation) -regularized image where background noise has been reduced. The masked image is then filtered by NLmeans (Non-Local Means) which reduces the noise in the text areas located by the mask. The document images to be enhanced are real historical documents from several periods which include several defects in their background. These defects result from scanning, paper aging and bleed-through. We observe the improvement of this enhancement method through OCR accuracy

    Adulteration of Dietary Supplements by the Illegal Addition of Synthetic Drugs: a review

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    In the last few years, the consumption of dietary supplements, especially those having plants as ingredients, has been increasing due to the common idea that they are natural products posing no risks to human health. In the European Union and the United States, dietary supplements are legally considered as foods/special category of foods, thus are not being submitted to any safety assessment prior to their commercialization. Among the issues that can affect safety, adulteration by the illegal addition of pharmaceutical substances or their analogs is of major concern since unscrupulous producers can falsify these products to provide for quick effects and to increase sales. This review discusses the various classes of synthetic drugs most frequently described as being illegally added to dietary supplements marketed for weight loss, muscle building/sport performance and sexual performance enhancement. Information regarding regulation and consumption is also presented. Finally, several conventional and advanced analytical techniques used to detect and identify different adulterants in dietary supplements and therefore also in foods, with particular emphasis on plant food supplements, are critically described. This review demonstrates that dietary supplement adulteration is an emerging food safety problem and that an effective control by food regulatory authorities is needed to safeguard consumers.This work was supported by European Union (FEDER funds through COMPETE) and Natl. Funds (FCT, Fundação para a Ciência e Tecnologia) through projects EXPL/DTP-SAP/1438/2013 (Safety of plant food supplements: searching for adulterant pharmaceutical drugs and plants) and LAQV UID/QUI/50006/2013.info:eu-repo/semantics/publishedVersio

    Knowledge Discovery in Documents by Extracting Frequent Word Sequences

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    published or submitted for publicatio

    Anisotropic Diffusion Partial Differential Equations in Multi-Channel Image Processing : Framework and Applications

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    We review recent methods based on diffusion PDE's (Partial Differential Equations) for the purpose of multi-channel image regularization. Such methods have the ability to smooth multi-channel images anisotropically and can preserve then image contours while removing noise or other undesired local artifacts. We point out the pros and cons of the existing equations, providing at each time a local geometric interpretation of the corresponding processes. We focus then on an alternate and generic tensor-driven formulation, able to regularize images while specifically taking the curvatures of local image structures into account. This particular diffusion PDE variant is actually well suited for the preservation of thin structures and gives regularization results where important image features can be particularly well preserved compared to its competitors. A direct link between this curvature-preserving equation and a continuous formulation of the Line Integral Convolution technique (Cabral and Leedom, 1993) is demonstrated. It allows the design of a very fast and stable numerical scheme which implements the multi-valued regularization method by successive integrations of the pixel values along curved integral lines. Besides, the proposed implementation, based on a fourth-order Runge Kutta numerical integration, can be applied with a subpixel accuracy and preserves then thin image structures much better than classical finite-differences discretizations, usually chosen to implement PDE-based diffusions. We finally illustrate the efficiency of this diffusion PDE's for multi-channel image regularization - in terms of speed and visual quality - with various applications and results on color images, including image denoising, inpainting and edge-preserving interpolation
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