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81.
Feng Ning Damien Delhomme Yann LeCun Fabio Piano Léon Bottou Paolo Emilio Barbano 《IEEE transactions on image processing》2005,14(9):1360-1371
We describe a trainable system for analyzing videos of developing C. elegans embryos. The system automatically detects, segments, and locates cells and nuclei in microscopic images. The system was designed as the central component of a fully automated phenotyping system. The system contains three modules 1) a convolutional network trained to classify each pixel into five categories: cell wall, cytoplasm, nucleus membrane, nucleus, outside medium; 2) an energy-based model, which cleans up the output of the convolutional network by learning local consistency constraints that must be satisfied by label images; 3) a set of elastic models of the embryo at various stages of development that are matched to the label images. 相似文献
82.
A SAXS method for the quantitative assessment of the morphology of polymer layered silicate nanocomposites is proposed. Fitting the SAXS patterns, the number of clay layers, the periodicity of the layers in the tactoids, the thickness of the regions interposed between the clay platelets and their distributions can be measured. A good agreement with TEM data was obtained, avoiding the inconsistencies with microscopical observations often reported in the literature. 相似文献
83.
Marcio Albuquerque de Souza Emilio Carlos Acocella Abraham Alcaim 《International journal of imaging systems and technology》2003,13(3):179-187
In order to attain perfect reconstruction, subband decomposition of arbitrarily shaped objects requires special strategies to deal with the decimation problem. One of the two strategies described in this paper (scheme 1) inserts pixels with amplitudes equal to the mean values of the neighboring ones belonging to the object. The requirement of transmitting (coding) these pixels reduces the coding gain and is avoided by the second strategy (scheme 2) examined in this paper. This strategy determines specific values of the pixels added to the object in such a way that they result in predefined amplitudes after decimation. For this reason, this method outperforms scheme 1. PSNR versus bit rate are presented for two objects. © 2003 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 179–187, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10054 相似文献
84.
Journal of Low Temperature Physics - We have investigated disorder phenomena in solid 4He near megting in presence of vacancies by means of Quantum Monte Carlo (MC) simulations using the Shadow... 相似文献
85.
86.
In this paper we analyze the determination of “key” sectors in the final energy consumption. We approach this issue from an input–output perspective and we design a methodology based on the elasticities of the demands of final energy consumption. As an exercise, we apply the proposed methodology to the Spanish economy. The analysis allows us to indicate the greater or lesser relevance of the different sectors in the consumption of final energy, pointing out which sectors deserve greater attention in the Spanish case and showing the implications for energy policy. 相似文献
87.
Alejandro Montes-García Jose María Álvarez-Rodríguez Jose Emilio Labra-Gayo Marcos Martínez-Merino 《Expert systems with applications》2013,40(17):6735-6741
The present paper introduces a context-aware recommendation system for journalists to enable the identification of similar topics across different sources. More specifically a journalist-based recommendation system that can be automatically configured is presented to exploit news according to expert preferences. News contextual features are also taken into account due to the their special nature: time, current user interests, location or existing trends are combined with traditional recommendation techniques to provide an adaptive framework that deals with heterogeneous data providing an enhanced collaborative filtering system. Since the Wesomender approach is able to generate context-aware recommendations in the journalism field, a quantitative evaluation with the aim of comparing Wesomender results with the expectations of a team of experts is also performed to show that a context-aware adaptive recommendation engine can fulfil the needs of journalists daily work when retrieving timely and primary information is required. 相似文献
88.
Luca Massimiliano Capisani Tullio Facchinetti Antonella Ferrara Alessandro Martinelli 《Journal of Intelligent and Robotic Systems》2013,71(2):159-178
Trajectory planning and tracking are crucial tasks in any application using robot manipulators. These tasks become particularly challenging when obstacles are present in the manipulator workspace. In this paper a n-joint planar robot manipulator is considered and it is assumed that obstacles located in its workspace can be approximated in a conservative way with circles. The goal is to represent the obstacles in the robot configuration space. The representation allows to obtain an efficient and accurate trajectory planning and tracking. A simple but effective path planning strategy is proposed in the paper. Since path planning depends on tracking accuracy, in this paper an adequate tracking accuracy is guaranteed by means of a suitably designed Second Order Sliding Mode Controller (SOSMC). The proposed approach guarantees a collision-free motion of the manipulator in its workspace in spite of the presence of obstacles, as confirmed by experimental results. 相似文献
89.
The roles of textural images in improving land-cover classification in the Brazilian Amazon 总被引:1,自引:0,他引:1
Dengsheng Lu Guiying Li Emilio Moran Luciano Dutra Mateus Batistella 《International journal of remote sensing》2013,34(24):8188-8207
Texture has long been recognized as valuable in improving land-cover classification, but how data from different sensors with varying spatial resolutions affect the selection of textural images is poorly understood. This research examines textural images from the Landsat Thematic Mapper (TM), ALOS (Advanced Land Observing Satellite) PALSAR (Phased Array type L-band Synthetic Aperture Radar), the SPOT (Satellite Pour l’Observation de la Terre) high-resolution geometric (HRG) instrument, and the QuickBird satellite, which have pixel sizes of 30, 12.5, 10/5, and 0.6 m, respectively, for land-cover classification in the Brazilian Amazon. GLCM (grey-level co-occurrence matrix)-based texture measures with various sizes of moving windows are used to extract textural images from the aforementioned sensor data. An index based on standard deviations and correlation coefficients is used to identify the best texture combination following separability analysis of land-cover types based on training sample plots. A maximum likelihood classifier is used to conduct the land-cover classification, and the results are evaluated using field survey data. This research shows the importance of textural images in improving land-cover classification, and the importance becomes more significant as the pixel size improved. It is also shown that texture is especially important in the case of the ALOS PALSAR and QuickBird data. Overall, textural images have less capability in distinguishing land-cover types than spectral signatures, especially for Landsat TM imagery, but incorporation of textures into radiometric data is valuable for improving land-cover classification. The classification accuracy can be improved by 5.2–13.4% as the pixel size changes from 30 to 0.6 m. 相似文献
90.
Radiation synthesis of a thermo-pH responsive binary graft copolymer (PP-g-DMAEMA)-g-NIPAAm by a two step
method 总被引:1,自引:1,他引:0
Summary (PP-g-DMAEMA)-g-NIPAAm was synthesized using gamma radiation from a 60Co
source. Graft polymerization of N,N’-dimethylaminoethylmethacrylate (DMAEMA) onto polypropylene (PP)
was accomplished in about 100 percent yield by the mutual irradiation technique at a dose of 10 kGy.
Grafting of N-isopropylacrylamide (NIPAAm) onto PP-g-DMAEMA was carried out by the pre-irradiation method
with doses from 20 to 100 kGy. The influence of temperature, reaction time, and monomer concentration
on grafting yield was studied. Grafting processes were confirmed by infrared spectroscopy (FTIR-ATR).
(PP-g-DMAEMA)-g-NIPAAm films were characterized by thermogravimetric analysis (TGA) and differential
scanning calorimetry (DSC). The lower critical solution temperature (LCST) and critical pH point of
the films were obtained by water contact angle and percent swelling measurements. The LCST was also
determined by DSC. We report here hare a new binary graft copolymer which shows two LCST values, synthesized
in two steps. 相似文献