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1.
2.
Borodina I. A. Zaitsev B. D. Kuznetsova I. E. Teplykh A. A. Shurygin V. V. 《Technical Physics Letters》2003,29(9):781-783
The conditions for hybridization of the zero-order and high-order acoustic waves propagating in a piezoelectric crystal plate have been studied. The dependence of the phase velocity of the hybrid waves on the parameter hf (h is the plate thickness and f is the wave frequency) is established for the potassium niobate and lithium niobate plates possessing various crystallographic orientations and conductivities. It is found that hybridization takes place when the conductivity of a thin surface layer exceeds a certain critical value, which can vary within broad limits depending on the plate material and orientation. The degree of dispersive repulsion of the coupled modes grows with increasing electromechanical coupling coefficient. 相似文献
3.
E. Kh. Shakhpazov I. G. Rodionova O. N. Baklanova A. I. Zaitsev D. A. Burko A. D. Gorin S. D. Zinchenko 《Metallurgist》2006,50(1-2):65-70
It is shown that the corrosion resistance of automobile sheet can be improved by ensuring that steels of this type have a
low content of corrosion-active nonmetallic inclusions (CANI). The main mechanisms responsible for the formation of CANI in
automobile sheet have been established, and recommendations have been developed to reduce their concentration in this product
• optimize the deoxidation processes that are used by ensuring that the proportions of the additions made to the steel are
consistent with the composition of the ladle slag and that certain key temperature-time parameters of these processes are
maintained
• control the composition of the ladle slag to prevent the formation of solid phases in the slag and their transfer to the
metal; certain conditions must also be observed in the argon blow and the introduction of the addtions.
Use of the above recommendations to make automobile sheet and tube steels cleaner with respect to their content of CANI and
thus help optimize out-of-furnace treatments at metallurgical and pipe plants will make it possible to improve the corrosion
resistance of metal products used in automotive manufacturing.
__________
Translated from Metallurg, No. 2, pp. 45–48, February, 2006. 相似文献
4.
V. G. Zaitsev 《Strength of Materials》1994,26(3):216-222
A study is made of the distribution law for the amplitudes of random stresses and associated parameters. A theoretical law is proposed to describe an empirical distribution, and a comparison is made between the deviations of the endurances corresponding to these laws and the coefficient of variation of random endurance values. An empirical formula is obtained to determine maximum stress amplitudes.Translated from Problemy Prochnosti, No. 3, pp. 63–70, March, 1994. 相似文献
5.
Conclusions Theoretical and practical results indicate that the SAA method can be efficiently applied for the solution of road construction optimization problems with allowance for construction dynamics.We have experimentally established the possibility of replacing the traditional static designs, based only on average initial data, with dynamic designs relying on accurate information about the current conditions. The dynamic designs can be used to develop the best managerial decisions for roadbed construction.Our results again emphasize the need for the development of a qualitatively new scientific-technical base of construction controls relying on integrated application of efficient mathematical methods and computing tools for the analysis and optimal revision of design, technological, and organizational solutions. Our research has led to the development (jointly with Glavbamstroi design office) of a proposal for a program of radical improvement of preparation in the construction industry by establishing an interactive link between CAD systems and MIS. The proposal has been approved by the college of the Ministry of Transportation Construction.This research is merely the first step toward the development of optimization algorithms for an integrated computerized management system for road construction, which should substantially accelerate the search for best design and managerial solutions by allowing sequential optimal revision of earlier alternatives in different stages of the life cycle of the project, strengthening the currently weak feedback from construction to design, and encouraging the experts to assume an active role in on-line search for the best man-machine solutions. Our results to a certain extent have stimulated the organization of design and construction associations, approved by the Resolution of the Central Communist Party of the USSR and the Council of Ministers of the USSR, whose function is to improve the economics of construction and in particular to accelerate large-scale adoption of research results in practice.In addition to the authors, many other researchers took part in this project: V. I. Biletskii (in the development of algorithms and programs and in running the line optimization computations for the longitudinal profile), V. V. Yatskevich (in improvement of programs and in running the earth mass distribution optimization), V. S. Belopol, I. A. Vasilevskii, G. M. Eremeev, E. V. Ivanov, A. P. Kozhevnikov, V. A. Maslov, Yu. B. Narusov, V. S. Plastun, I. S. Rozanov, A. A. Yakubov, V. F. Temnikov, V. A. Shamuratov, V. I. Avdonin, V. A. Baranov, and others (in substantive formulation of the problems, in organization of pilot work, in the analysis of the results, in the development of input data and generalization of the results).Translated from Kibernetika, No. 5, pp. 63–69, September–October, 1988. 相似文献
6.
S. N. Zaitsev 《Problems of Information Transmission》2016,52(4):391-399
Skew maximum-period polynomials (MP polynomials) are a kind of pseudorandom sequence generators with good cryptographic properties and efficient implementation on modern processors using parallelism technologies. There are two known classes of MP polynomials, presented in various papers (actually coinciding, as will be shown below), obtained constructively. Here we describe a wider class of skew MP polynomials. 相似文献
7.
A. V. Zaitsev Yu. D. Kislitsyn 《Journal of Computer and Systems Sciences International》2017,56(2):208-217
We propose a constructive algorithm for determining the guaranteed accuracy of estimating the state vector of an unperturbed linear dynamic system for an arbitrarily taken algorithm in the context of a problem with measuring errors that are limited in magnitude [1]. We also present the results of determining the measure of the guaranteed accuracy of estimation for the class of algorithms that minimize the Hölder norm. 相似文献
8.
D. A. Zaitsev 《Automatic Control and Computer Sciences》2012,46(7):345-355
An inhibitor Petri net with a fixed structure that executes an arbitrary given Markov normal algorithm is constructed. The algorithm and its input string are encoded by nonnegative integer numbers and put into dedicated places of the Petri net, which implements the application of the algorithm productions over the string of symbols. Rules of encoding sequential, branching, and cyclic processes by Petri nets are used. Upon completion of the net operation, the output string is restored (decoded) from the integer form of the representation. Within the paradigm of computations on Petri nets, the constructed net provides the compatibility of systems. 相似文献
9.
D. D. Zaitsev E. A. Gravchikova P. E. Kazin A. V. Garshev Yu. D. Tret’yakov M. Jansen 《Inorganic Materials》2006,42(3):326-330
Glasses with the nominal compositions SrFe12O19 + nNa2Sr2B4O9 (n = 4, 6, 8, 10) and SrFe12O19 + 6Na2Sr3B4O10 were prepared via rapid quenching of oxide melts and were then heat-treated between 500 and 800°C in order to produce glass-ceramics containing fine SrFe12O19 particles. The materials were characterized by x-ray diffraction, differential thermal analysis, electron microscopy, and magnetic measurements. The crystallization behavior of the glasses was investigated. The coercivity of the glass-ceramics was shown to increase with heat-treatment temperature, up to 486 kA/m. By dissolving the nonmagnetic matrix of the glass-ceramics with the nominal compositions SrFe12O19 + 6Na2Sr3B4O10 and SrFe12O19 + 4Na2Sr2B4O9, submicron-sized strontium hexaferrite particles were obtained. 相似文献
10.
D. D. Zaitsev P. E. Kazin A. V. Garshev Yu. D. Tret'yakov M. Jansen 《Inorganic Materials》2004,40(8):881-885
Glasses with nominal compositions of SrFe12O19 + 8SrB2O4 (I) and SrFe12O19 + 12Sr2B2O5 (II) are prepared by rapid quenching from the liquid state and are converted to glass-ceramics containing fine magnetic particles of SrFe12O19 by heat treatment between 600 and 950°C. The materials are characterized by x-ray diffraction, differential thermal analysis, electron microscopy, and magnetic measurements. The phase transformations accompanying glass crystallization are identified. The glass composition and heat-treatment conditions are shown to influence the aspect ratio of the forming submicron-sized strontium hexaferrite particles. The strongest coercive fields reached in glass-ceramics I and II are 504 and 456 kA/m, respectively. 相似文献