1,721,234 research outputs found
CIL:27851
No full textOne of the principal challenges in counting or segmenting nuclei is dealing with clustered nuclei. To help assess algorithms' performance in this regard, this synthetic image set consists of five subsets with increasing degree of clustering. Five subsets of 20 images each are provided. Each image contains 300 objects, but the objects overlap and cluster with overlap probability ranging from 0.0 to 0.6, and can be found with CIL 27833, 27853, 28754, 28734, and 28714, respectively. This image set has 0.0 probability overlap. The images were generated with the SIMCEP (http://www.cs.tut.fi/sgn/csb/simcep/tool.html) simulating platform for fluorescent cell population images (Lehmussola et al., IEEE T. Med. Imaging, 2007 and Lehmussola et al., P. IEEE, 2008). Ground truth for foreground/background segmentation are available as binary images as the second image in the tiff image stack.
Recommended citation We used the Synthetic 1 image set (Ruusuvuori et al., in Proc. of the 16th European Signal Processing Conference (EUSIPCO-2008), 2008), available from the Broad Bioimage Benchmark Collection (www.broad.mit.edu/bbbc)
Self-imaging technique for beam collimation
Get PDF© 2014 Optical Society of America. The authors thank to Jose Luis Vilas for his valuable comments. This work has been supported by the Ministry of Science and Innovation of Spain (project DPI2011-27851) and project Art. 83 LOU "Estudio de tecnologia para la realizacion de codificadores opticos de 2 mu m de periodo" with Fagor Automation S. Coop.A simple collimation technique based on measuring the period of one self-image produced by a diffraction grating is proposed. Transversal displacement of the grating is not required, and then automatic single-frame processing can be performed. The self-image is acquired with a CMOS camera, and the period is computed using the variogram function. Analytical and experimental results are obtained, which show the simplicity and accuracy of the proposed technique.Ministerio de Ciencia e Innovación (MICINN), EspañaFagor Automation S. CoopDepto. de ÓpticaFac. de Ciencias FísicasTRUEpu
Lissajous figure-based single-frame collimation technique
Get PDF© 2015 Elsevier B.V. This work has been supported by the Ministry of Science and Innovation of Spain (project DPI2011-27851).An accurate collimation technique based on a double grating system is proposed. Transversal displacement of the grating is not required and then, automatic single-frame processing can be performed. Talbot self-images are projected onto a mask composed by several shifted diffraction gratings. A Lissajous figure is obtained with the signals acquired by a CMOS camera where the mask is simulated by software. The collimation degree is determined by measuring the ellipticity of the Lissajous figure. Visual or automatic procedures for simple and accurate collimation of a light source are proposed. Experimental results are obtained which show a resolution of δϕ ≈ 4.16 μrad in the divergence of the beam when a lens with focal length f = 25 mm and diameter D = 20 mm is used for collimation.Ministerio de Ciencia e Innovación (MICINN), EspañaDepto. de ÓpticaFac. de Ciencias FísicasTRUEpu
Near field diffraction of cylindrical convex gratings
Get PDF© 2015 IOP Publishing Ltd. The authors thank Jose Maria Herrera-Fernandez for his help with graphics. This work has been supported by the project DPI2011-27851 of the Ministry of Science and Innovation of Spain and the project Fagor Automation-UCM Ref. 92/2014.We analyze the field produced by a cylindrical convex diffraction grating at the Fresnel regime for several kinds of light sources, including a monochromatic quasipunctual source, finite size, and polychromatic sources. These results can help one understand the functioning of rotary optical encoder technology. A decrease in the self-image contrast is produced for finite nonpunctual sources. In addition, the polychromaticity of the source affects the smoothness of the self-images, making them quasicontinuous from a certain distance from the grating forward. Finally, we experimentally validate the obtained analytical predictions.Ministerio de Ciencia e Innovación (MICINN), EspañaProject Fagor Automation-UCMUniversidad Complutense de Madrid (UCM)Depto. de ÓpticaFac. de Ciencias FísicasTRUEpu
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Near field of stacked diffraction gratings
No full text© 2013 Elsevier GmbH.
This work has been partially supported by projects DPI2011-27851 and INNPACTO “FORE”, IPT-020000-2010-9 of the Ministerio de Ciencia e Innovación of Spain.We obtain a general analytical formulation for determining the near field produced by N diffraction gratings disposed in stack using a scalar approximation. Parameters of the gratings such as type-amplitude/phase-, fill factors, periods and relative positions between gratings along the x and y axes are considered. The obtained formulation is useful for analyzing problems which involve several diffraction gratings, such as optical encoders since it is computationally faster than integral formulations. Finally, analytical results are compared with numerical simulations based on the Rayleigh–Sommerfeld equation.Ministerio de Ciencia e Innovación (MICINN), EspañaDepto. de ÓpticaFac. de Ciencias FísicasTRUEpu
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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