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41.
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Preliminary data analysis in the identification of multidimensional discrete–continuous processes is considered. A method is proposed for generating a working sample from an initial training sample consisting of normal operating data. The method somewhat resembles the bootstrap process. In the present case, the process begins with a training sample that reflects the properties of the object to be identified. By means of the proposed method, the unknown stochastic dependence at the limit of definition of the corresponding input–output variables for the object may be automatically derived. The identification of the oxygen-converter process in converter shop 2 at OAO EVRAZ ZSMK is considered in the case with insufficient available information and gaps in the observation sample. The model is based on a new working sample containing both the measurements and data generated by the proposed method. By using the working sample as a training sample, the precision of identification is doubled. 相似文献
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Russian Journal of Nondestructive Testing - To increase the speed of recording of echo signals and increase the speed of reconstruction of the image of reflectors, it is proposed to use a sparse... 相似文献
47.
V. S. Teslenko V. I. Rostovtsev K. A. Lomanovich A. P. Drozhzhin R. N. Medvedev 《Journal of Mining Science》2007,43(1):91-97
Absract The effect of electrical blast parameters is studied for grinding mineral materials by example of copper-nickel ore. It is
shown that the average energy consumed by the electrical blasting is within 5–50 J/g. The particle disintegration mechanism
has been considered at high and low electric conductivity of ore. It is established that grinding and separation of particles
by size are possible to be performed conjointly in the same apparatus.
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Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 100–107, January–February, 2007. 相似文献
48.
Enhanced transport properties of Sn-substituted proton-conducting BaZr0.8Sc0.2O3–δ ceramic materials
Inna A. Zvonareva Anna V. Kasyanova Artem P. Tarutin Gennady K. Vdovin Julia G. Lyagaeva Dmitry A. Medvedev 《Journal of the American Ceramic Society》2022,105(3):2105-2115
High-temperature proton conductors based on acceptor-doped barium zirconate exhibit excellent chemical stability in atmospheres containing CO2 or H2O. However, due to their refractory nature, these conductors have a low grain growth rate, which negatively affects the overall electrical conductivity. A possible strategy for increasing the ionic conductivity of zirconates lies in the partial substitution of Zr-ions with other isovalent dopants. In this work, we carried out systematic studies of the crystal structure, microstructure, hydration capacity, transport, and thermal properties of BaZr0.8–xSnxSc0.2O3–δ (x = 0, 0.1, and 0.2). According to X-ray powder diffraction and scanning electron microscopy data, all studied ceramic samples have a cubic perovskite structure, whose average grain size decreases with tin doping. It is found that the composition with x = 0.1 exhibits the highest values in terms of total, ionic, grain, and grain-boundary conductivities. The complex analysis of the obtained data shows that a low-level substitution of Zr4+- with Sn4+-ions is a competent approach for designing new proton-conducting electrolytes attractive for high-temperature applications. 相似文献
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O. N. Alyakrinskiy D. Yu. Bolkhovityanov P. V. Logachev A. M. Medvedev Yu. I. Semenov A. A. Starostenko 《Russian Engineering Research》2016,36(5):360-363
Thermal conditions for the additive manufacture of components by melting metal and alloy wire are presented. In an experiment, a prototype 3D printer is used to print components in vacuum. 相似文献
50.
E. F. Medvedev 《Glass and Ceramics》2001,58(7-8):235-238
The author analyzes certain parameters determining the structure of glasses, which ought to be taken into account in developing chemical compositions for microspheres, namely, the molar volume, the silicate modulus (for silicate glasses), the gas permeability coefficient, and the structure coherence factor. Furthermore, the parameter of internal porosity is proposed. 相似文献