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991.
Semiconductors - A model of a heterostructure consisting of a silicon-carbide single layer formed on a massive silicon substrate is proposed. The problem of the adsorption of alkali metal atoms and... 相似文献
992.
Baglov A. V. Chubenko E. B. Hnitsko A. A. Borisenko V. E. Malashevich A. A. Uglov V. V. 《Semiconductors》2020,54(2):228-232
Semiconductors - Interrelationship between the structure and optical properties of graphite-like semiconductor carbon nitride produced by the heat treatment of thiocarbamide in an oxygen-containing... 相似文献
993.
Kolmachikhina E. B. Sviridov A.V. Naumov K. D. 《Russian Journal of Non-Ferrous Metals》2020,61(5):488-493
Russian Journal of Non-Ferrous Metals - This article is devoted to the influence of sodium lignosulfonate (SL), anionic surfactants (sodium dodecylsulfate (SDS), sodium dodecylbenzene sulfonate... 相似文献
994.
Katok O. A. Kravchuk R. V. Kharchenko V. V. Rudnits’kyi M. P. Bisyk S. P. Davydovs’kyi L. S. Slyvins’kyi O. A. 《Strength of Materials》2020,52(5):715-721
Strength of Materials - The paper presents the indentation method for strength assessment of the welded joints in high-strength alloy steels, including base metal, heat-affected zone, and welded... 相似文献
995.
Traditionally, in supervised machine learning, (a significant) part of the available data (usually 50%-80%) is used for training and the rest—for validation. In many problems, however, the data are highly imbalanced in regard to different classes or does not have good coverage of the feasible data space which, in turn, creates problems in validation and usage phase. In this paper, we propose a technique for synthesizing feasible and likely data to help balance the classes as well as to boost the performance in terms of confusion matrix as well as overall. The idea, in a nutshell, is to synthesize data samples in close vicinity to the actual data samples specifically for the less represented (minority) classes. This has also implications to the so-called fairness of machine learning. In this paper, we propose a specific method for synthesizing data in a way to balance the classes and boost the performance, especially of the minority classes. It is generic and can be applied to different base algorithms, for example, support vector machines, k-nearest neighbour classifiers deep neural, rule-based classifiers, decision trees, and so forth. The results demonstrated that (a) a significantly more balanced (and fair) classification results can be achieved and (b) that the overall performance as well as the performance per class measured by confusion matrix can be boosted. In addition, this approach can be very valuable for the cases when the number of actual available labelled data is small which itself is one of the problems of the contemporary machine learning. 相似文献
996.
Kovalev I. D. Miloserdov P. A. Gorshkov V. A. Kovalev D. Yu. 《Russian Journal of Non-Ferrous Metals》2020,61(1):126-131
Russian Journal of Non-Ferrous Metals - A cast material based on the Nb2AlC MAX phase is formed by SHS metallurgy. The synthesis is performed using the Nb2O5–Al–C mixture with the... 相似文献
997.
Dorofeyev V. Yu. Sviridova A. N. Svistun L. I. 《Russian Journal of Non-Ferrous Metals》2020,61(3):354-361
Russian Journal of Non-Ferrous Metals - Rolling bearing rings comprise a large reserve for expanding powder metallurgy production. This reserve is being incompletely implemented. The hot forging of... 相似文献
998.
Journal of Communications Technology and Electronics - Abstract—The two-dimensional diffraction problem of a plane polarized TM-wave on two identical solid silver nanocylinders is considered.... 相似文献
999.
Akopdzhanyan T. G. Chemagina E. A. Borovinskaya I. P. 《Russian Journal of Non-Ferrous Metals》2020,61(6):686-690
Russian Journal of Non-Ferrous Metals - The synthesis and sintering of the (AlN)x(SiC)1 – x solid solution have been studied under conditions of self-propagating high-temperature synthesis... 相似文献
1000.
Scientometrics - The purpose of a doctorate is educating new researchers to later produce scientific articles derived from their doctoral thesis. The objective of this study is to verify if... 相似文献