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41.
MacDonald Angus W. III; Goghari Vina M.; Hicks Brian M.; Flory Janine D.; Carter Cameron S.; Manuck Stephen B. 《Canadian Metallurgical Quarterly》2005,19(6):814
Convergent and divergent validity are critically important in developing psychological measures that reveal interpretable deficits in disordered populations. This article reports on 2 studies that evaluated the validity of context processing measures. In Experiment 1, a confirmatory factor analysis of data from 481 healthy adults established the convergent validity of 2 context processing measures and showed that context processing accounted for significant amounts of variance in standard IQ and working memory measures. In Experiment 2, 20 schizophrenia patients, 16 of their healthy siblings, and 28 controls were evaluated using a novel, short context processing measure, the dot pattern expectancy (DPX) task. The DPX was sensitive to specific deficits in schizophrenia patients and their healthy siblings. These findings support the construct validity of context processing measures, suggest context processing is a component of intellectual functioning, and demonstrate that brief context processing measures remain sensitive to psychopathological deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
Stephen O. Dean 《Journal of Fusion Energy》2003,22(3):181-190
This paper summarizes recent progress in fusion Innovative Confinement Concepts (ICC) as reported at the 2004 ICC Workshop held May 25–28, 2004 in Madison, Wisconsin. This was the third in an annual series of workshops on this topic. The purpose of these workshops is to provide a forum for those who are thinking and working beyond what is considered to be the current state of understanding of fusion concepts. 相似文献
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44.
Velocity Distribution in the Roughness Layer of Rough-Bed Flows 总被引:1,自引:0,他引:1
Vladimir Nikora Katinka Koll Ian McEwan Stephen McLean Andreas Dittrich 《Canadian Metallurgical Quarterly》2004,130(10):1036-1042
Several models for the vertical distribution of the double-averaged (in time and in the plane parallel to the mean bed) longitudinal velocity in the flow region between roughness troughs and roughness tops are suggested. We found that the same model for velocity distribution may be applicable to a range of flow conditions and roughness types, which share some common features. The suggested models for velocity distribution in the near-bed region are: (1) Constant velocity; (2) exponential velocity distribution; and (3) linear velocity distribution. The measured velocity distributions may be approximated by a single model or by a combination of models depending on roughness geometry and flow conditions. The validity of these models for velocity distribution is supported by laboratory data. 相似文献
45.
The classification of agricultural tillage systems has proven challenging in the past using traditional classification methods due to the similarity of spectral reflectance signatures of soils and senescent crop residues. In this study, five classification methods were examined to determine the most suitable classification algorithm for the identification of no-till (NT) and traditional tillage (TT) cropping methods: minimum distance (MD), Mahalanobis distance, Maximum Likelihood (ML), spectral angle mapping (SAM), and the cosine of the angle concept (CAC). A Landsat ETM+ image acquired over southern Michigan and northern Indiana was used to test these classification methods. Each classification method was validated with 293 ground truth sampling locations collected commensurate with the satellite overpass. Classification accuracy was then assessed using error matrix analysis, Kappa statistics, and tests for statistical significance. The results indicate that of the classification routines examined, the two spectral angle methods were superior to the others. The cosine of the angle concept algorithm outperformed all the other classification routines for tillage practice identification and mapping, yielding an overall accuracy of 97.2% (Kappa=0.959). 相似文献
46.
Stephen Mason 《Computer Fraud & Security》2004,2004(3):6-13
Technology has long been used in the process of voting, and the use of electronic machines was introduced in the United States of America in the 1970s. More recently, vendors have encouraged the use of remote electronic voting methods, and politicians have begun to consider such options, including the use of the Internet, telephone, text messaging and interactive digital television. This paper considers some of the practical and security issues that affect remote electronic voting. 相似文献
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Results from wear studies in repetitive impact sliding are described in this paper. The material pair studied consisted of steel CPM-10V (specimen) (where CPM denotes crucible particle metallurgy) and 17-4 precipitationhardened (PH) steel (counterface) with transverse sliding velocities of 4 and 8 m s?1. By means of scanning electron microscopy, energy-dispersive analysis of X-rays and X-ray diffraction methods it is shown that the wear is due to a material transport of the counterface 17-4 PH steel to the CPM-10V surface. In the wear process, a change in microhardness of the counterface substrate is apparent, and X-ray diffraction of debris confirms the presence of transformed metal. These products include γ-Fe together with trace amounts of α-Fe2O3; however, virtually no carbide from the CPM-10V steel was detected. 相似文献
49.
Scanning electron microscope (SEM) tribometric data on polycrystalline silicon (poly-Si) vs. poly-Si, Si(100) vs. Si(100)
and Si(111) vs. Si(111) interfaces, obtained in
Torr and in 0.2 Torr partial pressure of hydrogen gas (
) from room temperature to 850°C, were performed under standard and much slower thermal ramping rates. The friction data were analyzed per the methodology
described in part I of this paper series. The results indicate a highly beneficial friction- and wear-reducing regime within
a relatively narrow thermal region. This desirable region coincides with some chemisorption of excited species of molecular
hydrogen just before the mass thermal desorption of surface hydrides. These data represent the tribochemical equivalent of
a method routinely used in electronics, whereby deep electron traps (dangling Si bonds) are passivated by baking in molecular
hydrogen. The
also exerts a moderating influence on the size of the friction noise at all test temperatures. However, the general level
of friction beyond the beneficial thermal region is high. In parallel, the general wear rate of Si representative of the entire
range of standard thermal ramping in both atmospheric environments is in the extremely high 10-12m3/(N m) range. Operating strictly in the beneficial, low-friction thermal regime resulted in a several orders-of-magnitude
reduction in the wear rate over those measured under standard thermal ramping conditions. Although the results confirm previous
findings that Si is not a good material of construction for miniaturized moving mechanical assemblies (e.g., microbearings
and gears), there seems to be some limited possibility of gas-phase lubrication of Si micromechanisms with rarefied hydrogen
at surface temperatures between 100 and 300°C.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
50.