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71.
72.
采用学习—测试二阶段实验范式,对比了类别标签与类别特征在类别特征推理中的极化效应.研究结果表明,在类别标签组,标签匹配项目上的特征推理分数显著高于标签不匹配项目上的特征推理分数;在特征标签组,标签匹配项目上的特征推理分数与标签不匹配项目上的特征推理分数之间差异不显著.类别标签组的失匹配分数显著高于特征标签组.即在类别特征推理任务中,类别标签的极化效应显著高于类别特征的极化效应,因此,类别标签与类别特征存在本质差异,类别标签在类别特征推理中起主导作用.而且,本研究还发现,高前提概率条件下的特征推理分数都显著高于低前提概率条件下的特征推理分数,所以,前提概率也影响类别特征推理任务. 相似文献
73.
Abstract A quasicrystalline Al-Fe phase has been formed by room-temperature ion mixing of AI-Fe multiple layers with no additional postannealing. The quasicrystalline phase was dispersed as grain in an amorphous matrix. The size of the grains was about 10-30nm, and the composition was determined to be Al80Fe20. The structure of the quasicrystalline phase was identified by calculating some 20 sharp diffraction rings in the selected-area diffraction pattern and found to be similar to that of the rapidly quenched AI-Mn quasicrystalline phase. 相似文献
74.
Y. Z. Liu X. T. Zu J. Lian L. Wang X. Q. Huang Z. G. Wang 《Philosophical Magazine Letters》2013,93(11):705-712
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer. 相似文献
75.
The compressive deformation and fracture features of Zr59Cu20Al10Ni8Ti3 bulk metallic glassy samples with aspect ratios in the range of 0.67–2.00 have been investigated. The compressive plastic strain of the glass monotonically increases with decreasing aspect ratio, but the maximum strength almost maintains a constant value of 1.77–1.88?GPa. All the compressive shear-band angles are equal to?~40° if modified by the rotation of the primary shear bands. 相似文献
76.
77.
The grain size variation in a gradient surface produced by a punching and recovery process on a Cu-30Ni alloy has been observed by atomic force microscopy. The friction characteristics of the gradient surface in a 3.5 wt% NaCl solution were investigated using a micro-indenter probe, a pin-on-disc type tribometer, a strain sensor and an optical microscope. The results showed that the hardness and grain size can be well represented by the Hall–Petch relationship when the gain size is more than 30?nm. The wear rate, friction coefficient and adhesive force all increase depth below the surface. These variations are attributed to a gradual increasing grain size with depth. The morphologies of the worn track were also studied to understand further the corrosive wear behaviour of gradient surfaces. 相似文献
78.
Armando X. Estrada Tahira M. Probst Jeremiah Brown Maja Graso 《Military psychology》2013,25(2):220-236
We use classical test theory (CTT) and item response theory (IRT) methodologies to examine the psychometric and measurement properties of an instrument designed to assess sexual orientation harassment among military personnel (N?=?71,989). CTT analyses indicated that items were unidimensional and exhibited adequate levels of reliability. IRT analyses demonstrated that the items functioned similarly and exhibited appropriate levels of item discrimination. However, the analyses also suggested that the sensitivity of the items may be limited. Differential test functioning analyses provided evidence of the measurement equivalence of the instrument across male and female respondents. The findings provide support for the psychometric properties and measurement equivalence of the instrument for measuring sexual orientation harassment among male and female military personnel. We discuss the implications of our findings for future research on sexual orientation harassment in the workplace. 相似文献
79.
80.
S. X. Dou J. P. Zhou N. Savvides A. J. Bourdillon C. C. Sorrell N. X. Tan 《Philosophical Magazine Letters》2013,93(2):149-153
Abstract Superconducting and mechanical properties of Y1 Ba2Cu3 O7 can be improved by the use of sintering aids. 0·2 wt% of finely divided laser-ablated platinum powder has been mixed with the parent material and produced a dense product with exaggerated grain growth and improved critical current density and Vickers hardness. At higher concentrations of platinum, while the mechanical properties are further improved, the increased density appeared to inhibit access of oxygen for the tetragonal to orthorhombic phase transition and the current density was reduced. 相似文献