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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
According to D. E. Broadbent's (1958) selective filter theory, people do not process unattended stimuli beyond the analysis of basic physical properties. This theory was later rejected on the basis of numerous findings that people identify irrelevant (and supposedly unattended) stimuli. A careful review of this evidence, however, reveals strong reasons to doubt that these irrelevant stimuli were in fact unattended. This review exposed a clear need for new experiments with tight control over the locus of attention. The authors present 5 such experiments using a priming paradigm. When steps were taken to ensure that irrelevant stimuli were not attended, these stimuli produced no priming effects. Hence, the authors found no evidence that unattended stimuli can be identified. The results support a modern version of Broadbent's selective theory, updated to reflect recent research advances. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
The possibility of optimum filtration of the radiation of a mercury arc lamp for subterahertz Hilbert-transform spectroscopy with a frequency-selective Josephson detector is demonstrated. Hilbert-transform spectroscopy was used for the first time for measuring the transmission spectrum of a high-pass filter. 相似文献
993.
994.
A study is made of the statistical characteristics of isotropic velocity and scalar fields in supply of the kinetic energy
of turbulence from the energy of the average flow. Two models based on the distributions of the kinetic turbulence energy
and the intensity of scalar-field pulsations by wave numbers and length scales are used for calculation of the statistical
characteristics of turbulent velocity and scalar fields. The calculation results are compared to the data of the direct numerical
modeling performed under the same initial conditions.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 79, No. 1, pp. 148–154, January–February, 2006. 相似文献
995.
A stochastic model is proposed for a basic mechanism in the formation of uncertainties in physical quantity measurements.
__________
Translated from Izmeritel'naya Tekhnika, No. 1, pp. 12–17, January, 2006. 相似文献
996.
997.
Yu. V. Alekseev G. Yu. Alekseev V. A. Bityurin A. V. Plaskeev 《Protection of Metals》2006,42(6):526-531
A simplified topokinetic dissolution model of a solid taking into account the correlation between the dissolution rate and
the atomic surface topography enables one to interpret a linear (in semilogarithmic coordinates) segment of the steady-state
curves of the active anodic dissolution of metals. Its slope corresponds to the product of a concentration of kinks and the
elementary reaction rate, both of which exponentially depend on the potential, rather than a simple (Tafel) elementary rate
of the atom dissolution at a semi-crystal kink.
Original Russian Text ? Yu.V. Alekseev, G.Yu. Alekseev, V.A. Bityurin, A.V. Plaskeev, 2006, published in Zashchita Metallov,
2006, Vol. 42, No. 6, pp. 568–573. 相似文献
998.
Gerasimov S. A. Zhikharev A. V. Berezina E. V. Zubarev G. I. Pryanichnikov V. A. 《Metal Science and Heat Treatment》2004,46(1-2):13-17
The main laws of formation of structure and properties of nitrided structural steels are studied depending on their composition, parameters of preliminary heat treatment, and nitriding modes. New factors controlling the structure and operational properties based on new concepts of the mechanism of formation of nitride particles in the nitriding process are determined. 相似文献
999.
Transformations in machining. Part 1. enhancement of wavelet transformation neural network (WT-NN) combination with a preprocessor 总被引:2,自引:0,他引:2
X. Wang P. Chen I.N. Tansel Yenilmez A 《International Journal of Machine Tools and Manufacture》2006,46(1):36-42
Properly selected transformation methods obtain the most significant characteristics of metal cutting data efficiently and simplify the classification. Wavelet Transformation (WT) and Neural Networks (NN) combination was used to classify the experimental cutting force data of milling operations previously. Preprocessing (PreP) of the approximation coefficients of the WT is proposed just before the classification by using the Adaptive Resonance Theory (ART2) type NNs. Genetic Algorithm (GA) was used to estimate the weights of each coefficient of the PreP. The WT-PreP-NN (ART2) combination worked at lower vigilances by creating only a few meaningful categories without any errors. The WT-NN (ART2) combination could obtain the same error rate only if very high vigilances are used and many categories are allowed. 相似文献
1000.
B. P. Mikhaĭlov I. A. Rudnev P. V. Bobin A. R. Kadyrbaev A. B. Mikhaĭlova S. V. Pokrovskiĭ 《Technical Physics Letters》2006,32(10):901-903
We present the results of investigation of the magnetic, transport, structural, and mechanical properties of composites obtained by introducing finely dispersed zirconium nitride into a matrix of a Bi2Sr2Ca2Cu3O10 + δ (Bi2223) high-temperature superconductor. It is established that the introduction of ZrN particles in the range of very small concentrations (0.1–0.3 wt %) leads to a significant (more than threefold) increase in the critical current density of Bi2223 and increases the density of the composite, while the microhardness of the superconducting phase remains unchanged. 相似文献