1,721,261 research outputs found
Segmentation, recognition and tracing analysis for high-content cell-cycle screening
No full textWe present in this paper some new and efficient algorithms for segmentation, recognition and tracing analysis of cell phases for high-content screening. The conceptual frameworks are based on the morphological structures of cells where a series of morphological structural points are established. Furthermore, we address the issue of touching cells and then propose morphological techniques for cell separation, reconstruction and tracing analysis. The new segmentation method can resolve the question of over-segmentation. The tracing analysis of cell phases is based on cell shape, geometrical features and difference information of corresponding neighbor frames. Experiment results test the efficiency of the new metho
Modeling of Subsurface Tile Drainage using MIKE SHE
Full text linkAccurate estimation of subsurface drainage flow is essential for effectively evaluating the performance of management strategies in tile-drained landscapes. The objectives of this study were to calibrate and validate MIKE SHE for simulating subsurface tile drainage flow in central Iowa and to evaluate the simulated impact of two specific management strategies on tile flow. The model was calibrated and validated using the measured daily drainage in a 15.2 × 38 m row-cropped plot during 2006-2009 with a split-sample method. Drainage time constant and macropore flow were found to be important in predicting drainage flow. The calibrated drainage time constant of 5.6 h was outside the recommended range, which might be attributed to the shorter response time of subsurface flow at the plot scale used in this study. The calibrated model showed a satisfactory performance in simulating daily tile drainage flow with Nash-Sutcliffe model coefficient values of 0.78 and 0.73 for the calibration and validation periods, respectively. The measured and predicted total drainage from 2006-2009 were 865 and 958 mm, respectively. The results suggest that MIKE SHE has potential for predicting tile drainage flows; guiding management decisions and for assessment of drainage design of water flow to downstream water bodies.This article is published as Zhou, Xiaobo, Matthew Helmers, and Zhiming Qi. "Modeling of subsurface tile drainage using MIKE SHE." Applied Engineering in Agriculture 29, no. 6 (2013): 865-873. DOI: 10.13031/aea.29.9568. Copyright 2013 American Society of Agricultural and Biological Engineers. Posted with permission
Secure SWIPT for directional modulation aided AF relaying networks
No full textSecure wireless information and power transfer based on directional modulation is conceived for amplify-andforward (AF) relaying networks. Explicitly, we first formulate a secrecy rate maximization (SRM) problem, which can be decomposed into a twin-level optimization problem and solved by a one-dimensional (1D) search and semidefinite relaxation (SDR) technique. Then in order to reduce the search complexity, we formulate an optimization problem based on maximizing the signal-to-leakage-AN-noise-ratio (Max-SLANR) criterion, and transform it into a SDR problem. Additionally, the relaxation is proved to be tight according to the classic Karush-Kuhn- Tucker (KKT) conditions. Finally, to reduce the computational complexity, a successive convex approximation (SCA) scheme is proposed to find a near-optimal solution. The complexity of the SCA scheme is much lower than that of the SRM and the Max-SLANR schemes. Simulation results demonstrate that the performance of the SCA scheme is very close to that of the SRM scheme in terms of its secrecy rate and bit error rate (BER), but much better than that of the zero forcing (ZF) scheme.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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