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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
V. P. Beskachko O. A. Golovnya A. E. Korenchenko 《Journal of Engineering Physics and Thermophysics》2007,80(1):132-135
The results of a numerical solution of the problem of vibrations of a torsion viscosimeter filled with an incompressible viscoplastic
liquid are presented. It has been shown that in the vicinity of the rotation axis there appears a dead zone, whose boundary
changes in the process of vibrations. The influence of plastic properties of the liquid on the characteristics of viscosimeter
vibrations has been determined. A method for identifying viscoplastic properties by the observed parameters of vibrations
is proposed.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 1, pp. 124–127, January–February, 2007. 相似文献
992.
993.
V. V. Emtsev P. Ehrhart D. S. Poloskin K. V. Emtsev 《Journal of Materials Science: Materials in Electronics》2007,18(7):711-714
Production processes of electrically active defects in degenerate silicon subjected to 2.5 MeV electron irradiation at T = 4.2 K and T = 300 K have been studied. The production rates of primary and secondary defects in irradiated samples are analyzed on the basis
of the known properties of radiation-produced defects in Si. It has been demonstrated that a striking difference in the production
rates of electrically active defects in n- and p-Si under irradiation at cryogenic temperatures may be related to the different
fate of Frenkel pairs in both materials. The production rate of primary defects in degenerate Si was found to be between 1.5 cm−1 and 2 cm−1. 相似文献
994.
995.
996.
This paper presents new inverse modeling for synchronous reluctance motor (SyRM). This modeling is valid when the inductances are sinusoidal or nonsinusoidal and even when the machine is saturated. This technique involves the generation of constant torque curves as a function of two-phase currents in the Concordia's reference frame when the rotor angle is fixed. We also introduce an experimental method to obtain directly the inverse modeling. This practical method takes into account the saturation of the motor. This technique allows the reduction of the low torque ripple in the case of nonsinusoidal inductances. 相似文献
997.
998.
999.
Hyun-Chul Kim Author VitaeDaijin KimAuthor Vitae Sung Yang Bang Author Vitae 《Pattern recognition》2003,36(5):1095-1105
Linear discriminant analysis (LDA) is a data discrimination technique that seeks transformation to maximize the ratio of the between-class scatter and the within-class scatter. While it has been successfully applied to several applications, it has two limitations, both concerning the underfitting problem. First, it fails to discriminate data with complex distributions since all data in each class are assumed to be distributed in the Gaussian manner. Second, it can lose class-wise information, since it produces only one transformation over the entire range of classes. We propose three extensions of LDA to overcome the above problems. The first extension overcomes the first problem by modelling the within-class scatter using a PCA mixture model that can represent more complex distribution. The second extension overcomes the second problem by taking different transformation for each class in order to provide class-wise features. The third extension combines these two modifications by representing each class in terms of the PCA mixture model and taking different transformation for each mixture component. It is shown that all our proposed extensions of LDA outperform LDA concerning classification errors for synthetic data classification, hand-written digit recognition, and alphabet recognition. 相似文献
1000.
P. A. Borodovskii A. F. Buldygin A. S. Tokarev E. V. Chernyavskii 《Russian Microelectronics》2005,34(5):316-324
A further investigation is conducted into a new microwave method for evaluating bulk lifetime in silicon ingots 相似文献