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31.
Daniel B. Carr Anthony R. Olsen Suzanne M. Pierson Jean-Yves P. Courbois 《Data mining and knowledge discovery》2000,4(1):43-67
The paper introduces linked micromap (LM) plots for presenting environmental summaries. The LM template includes parallel
sequences of micromap, label, and statistical summary graphics panels with attention paid to perceptual grouping, sorting
and linking of the summary components. The applications show LM plots for Omernik Level II Ecoregions. The summarized United
States continental data includes USGS digital elevation, 30-year normal precipitation and temperature, and 8 million AVHRR
pixels classified into 159 types of land cover. One LM plot uses a line-height glyph to represent all 159 land cover percentages
per ecoregion. LM plots represent new visualization methodology that is useful in the data and knowledge based pattern representation
and knowledge discovery process. The LM plots focus on providing an orienting overview. The overview provides a starting place
for subsequent drilling down to what could otherwise be viewed as an overwhelming mass of data. The overview also provides
a starting place to learn about the intellectual structure that lies behind the notion of ecoregions and begins to connect
this abstract structure to quantitative methods. 相似文献
32.
Baudouin Jean-Yves; Vernet Mathilde; Franck Nicolas 《Canadian Metallurgical Quarterly》2008,22(3):313
This study investigated the processing of second-order relational face information in schizophrenia. Twenty-eight schizophrenic patients and 28 controls were asked to say whether the space between the eyes was the same in 2 side-by-side faces. The 2 faces were derived from the same original face, but the spacing between the eyes was either the same or differed by various distances. The results showed that schizophrenic patients needed a space that was twice as great as controls to see a difference. The authors conclude that schizophrenic patients have a deficit in processing second-order relational face information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
My Ahmed Said Azizi Samir Arauca Montero Mateos Jean-Yves Sanchez 《Electrochimica acta》2004,49(26):4667-4677
Nanocomposite polymer electrolytes based on a plasticized high molecular weight poly(oxyethylene) (POE) reinforced with high aspect ratio cellulose nanoparticles were reported. The influence of tetra(ethylene) glycol dimethyl ether (TEGDME) as plasticizer is investigated. The study mainly focuses on the dynamic mechanical behavior and ionic conductivity performances. The miscibility of the blend POE/TEGDME was investigated using both thermal and mechanical investigations. Viable polymer electrolytes can be obtained from this combination, conciliating acceptable ionic conductivities and outstanding mechanical performances on a large temperature range. 相似文献
34.
Weihua Zhuang Abbas Yongacoglu Jean-Yves Chouinard 《International Journal of Satellite Communications and Networking》1995,13(3):159-169
Mobile satellite communication systems at Ka/K band (30/20 GHz) are attractive because of their large bandwidth availability and potentiality to support smaller earth-stations and satellite antennas compared with L-band (1·6/1·5 GHz) systems. In this paper, multiple-symbol Viterbi decoding and dual-space equal-gain diversity reception for trellis-coded differential M-ary phase-shift-keying (DPSK) modulation are investigated as two mitigation techniques for severe channel impairments expected from a land mobile satellite communication channel at K band and, for comparison purposes, at L band. The multiple-symbol Viterbi decoder (MSVD) is a modified Viterbi decoder with inputs from multiple differential detectors. The channel is modelled as Rayleigh distributed multipath fading with a lognormally distributed line-of-sight (LOS) component due to shadowing. Four trellis-coded modulation (TCM) schemes are studied. The dependency of the system performance improvement on the decoder structure, the TCM scheme, and the system RF frequency band is presented. 相似文献
35.
An investigation into the antimicrobial mechanisms of action of two contact lens biocides using electron microscopy. 总被引:1,自引:0,他引:1
Caroline E Codling Anthony C Hann Jean-Yves Maillard A Denver Russell 《Contact lens & anterior eye》2005,28(4):163-168
Polyquaternium-1 (PQ-1) and myristamidopropyl dimethylamine (MAPD) are biocides used commercially in a contact lens disinfecting solutions. Electron microscopy was used to provide further evidence on the mechanism(s) of action of these agents against a wide range of ocular pathogens including bacteria, fungi and protozoa. Both PQ-1 and MAPD caused multiple forms of damage to the organisms tested, evidenced by structural alterations, blebbing, leakage and cell destruction. The extent of damage and the selectivity against specific type of microorganisms was consistent with the antimicrobial activity of these agents. Although electron microscopy is a powerful tool, it has its limitations when used to examine the mode of action of biocides. Indeed, there was no evidence of gross structural alteration to Acanthamoeba castellani or Aspergillus fumigatus following treatment. 相似文献
36.
Two experiments were carried out to study the role of gender category in evaluations of face distinctiveness. In Experiment 1, participants had to evaluate the distinctiveness and the femininity-masculinity of real or artificial composite faces. The composite faces were created by blending either faces of the same gender (sexed composite faces, approximating the sexed prototypes) or faces of both genders (nonsexed composite faces, approximating the face prototype). The results show that the distinctiveness ratings decreased as the number of blended faces increased. Distinctiveness and gender ratings did not covary for real faces or sexed composite faces, but they did vary for nonsexed composite faces. In Experiment 2, participants were asked to state which of two composite faces, one sexed and one nonsexed, was more distinctive. Sexed composite faces were selected less often. The results are interpreted as indicating that distinctiveness is based on sexed prototypes. Implications for face recognition models are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
37.
Through the variation of their cross sections, the in vivo response of lower back muscles to low loading in an upright seated posture is explored by the Fourier-transform profilometry technique. The maximization of its sensitivity allows us to reach an adequate resolution for the evaluation of low-back displacements. Refinements of the fringe pattern analysis permit the minimization of errors. The experiments show an asymmetric distribution of the displacement during head rotation movements. Significant contribution of the lower back to grasping exertions is also observed. These results are thought to be useful for early defect detection in the lower back. 相似文献
38.
Nicolas Dobigeon Saïd Moussaoui Jean-Yves Tourneret Cdric Carteret 《Signal processing》2009,89(12):2657
This paper addresses the problem of separating spectral sources which are linearly mixed with unknown proportions. The main difficulty of the problem is to ensure the full additivity (sum-to-one) of the mixing coefficients and non-negativity of sources and mixing coefficients. A Bayesian estimation approach based on Gamma priors was recently proposed to handle the non-negativity constraints in a linear mixture model. However, incorporating the full additivity constraint requires further developments. This paper studies a new hierarchical Bayesian model appropriate to the non-negativity and sum-to-one constraints associated to the sources and the mixing coefficients of linear mixtures. The estimation of the unknown parameters of this model is performed using samples obtained with an appropriate Gibbs algorithm. The performance of the proposed algorithm is evaluated through simulation results conducted on synthetic mixture data. The proposed approach is also applied to the processing of multicomponent chemical mixtures resulting from Raman spectroscopy. 相似文献
39.
This paper proposes a case study of the design of robust control for flexible axes. Robust parametric methods are worked out, and an heuristic initial tuning of the PID controller is proposed from additional pole-placement constraints on the rigid mode. Experimental validations highlight the relevance of adequate closed-loop control and trajectory planning design. 相似文献
40.
Auffan M Achouak W Rose J Roncato MA Chanéac C Waite DT Masion A Woicik JC Wiesner MR Bottero JY 《Environmental science & technology》2008,42(17):6730-6735
Iron-based nanoparticles have been proposed for an increasing number of biomedical or environmental applications although in vitro toxicity has been observed. The aim of this study was to understand the relationship between the redox state of iron-based nanoparticles and their cytotoxicity toward a Gram-negative bacterium, Escherichia coli. While chemically stable nanoparticles (gammaFe2O3) have no apparent cytotoxicity, nanoparticles containing ferrous and, particularly, zerovalent iron are cytotoxic. The cytotoxic effects appear to be associated principally with an oxidative stress as demonstrated using a mutant strain of E. coli completely devoid of superoxide dismutase activity. This stress can result from the generation of reactive oxygen species with the interplay of oxygen with reduced iron species (Fe(II) and/or Fe(0)) or from the disturbance of the electronic and/or ionic transport chains due to the strong affinity of the nanoparticles for the cell membrane. 相似文献