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81.
A method of processing complex signals in passive multi-element antenna arrays based on an analysis of the natural values of the correlation matrix of the signal is considered. By means of the method it is possible to substantially increase the output signal-to-noise ratio. An iterational process by means of which optimal estimators of both the signal and the amplitude-phase distribution may be obtained, is proposed. Theoretical estimators of the efficiency of the method are given. It is proved that, in terms of the efficiency, the approach considered in the article comes close to the technique of matched filtration. Results of statistical modeling that confirm the statistical results are presented. 相似文献
82.
Cunningham Stacey C.; Corrigan Sheila A.; Malow Robert M.; Smason Ivan H. 《Canadian Metallurgical Quarterly》1993,7(4):246
Assessed the differences between cocaine- and cocaine-plus-alcohol-dependent inpatients along several psychological variables. Of the 144 men that served as Ss, 113 were cocaine dependent and 31 were dependent on both cocaine and alcohol (CD-AD). CD-AD Ss showed significantly more symptoms of depression and anxiety and were more likely to have antisocial and avoidant personality disorders. The CD-AD group scored higher overall on the MMPI clinical scales. Results suggest that patients dependent on both cocaine and alcohol require increased attention to psychopathology during treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
S. M. Barinov D. A. Ivanov V. Ya. Shevchenko G. A. Fomina 《Journal of Materials Science》1992,27(20):5558-5560
Fracture experiments under conditions of subcritical crack extension were performed with double torsion and single-edge notched bend specimens of different alumina-based ceramic composites having layered granular structure. It is shown that it is possible to increase significantly the work-of-fracture as a result of layered granular structure organization. The pecularities of structure influence on the crack propagation kinetics were investigated, and the possibilities of acceleration and deceleration of subcritical crack growth are reported. 相似文献
84.
85.
V. N. Shevchenko N. M. Ivanov Yu. A. Zvezdina 《Optoelectronics, Instrumentation and Data Processing》2007,43(1):1-6
A non-quadratic regularization algorithm modification is proposed. It ensures identifying and filtering angular spectrum false components by choosing regularizing functional parameters. The algorithm efficiency was proved by modeling while solving the problem of multibeam wavefield division using one input data realization. 相似文献
86.
Ivan Cimrák 《Archives of Computational Methods in Engineering》2007,15(3):277-309
The Landau-Lifshitz (LL)equation of micromagnetism governs rich variety of the evolution of magnetization patterns in ferromagnetic
media. This is due to the complexity of physical quantities appearing in the LL equation. This complexity causes also an interesting
mathematical properties of the LL equation: nonlocal character for some quantities,nonconvex side-constraints, strongly nonlinear
terms. These effects influence also the numerical approximations. In this work, recent developments on the approximation of
weak solutions, together with the overview of well-known methods for strong solutions,are addressed.
Author is supported by the Fund for Scientific Research - Flanders FWO (Belgium). 相似文献
87.
A. S. Gouralnik N. G. Galkin V. A. Ivanov M. V. Ivanchenko E. A. Chusovitin 《Instruments and Experimental Techniques》2007,50(3):408-410
The design of a simple pulse-type evaporator ensuring a high rate (up to ~104 nm/s) of deposition of thin films (0.01–100 nm thick) onto a solid surface in ultrahigh vacuum is described. The evaporation pulse is created by discharge of a capacitor bank via a fast-response evaporator produced from a tungsten foil. Results illustrating the efficiency of this device are presented. 相似文献
88.
89.
A. V. Ivanov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(6):327-331
Successful introduction of pisciculture to reservoirs by the method of migratory fish-farm pasturing is described.
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Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 9, September 2007, pp. 36–40. 相似文献
90.