(Vestsi Natsiyanalnai Akademii Navuk Belarusi)
SERIES OF PHYSICAL-MATHEMATICAL SCIENCES
Published by Belaruskaya Navuka Publishing House, Minsk, Republic of Belarus
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Proceedings of the National Academy of Sciences of Belarus (Vestsi Natsiyanalnai Akademii Navuk Belarusi) SERIES OF PHYSICAL-MATHEMATICAL SCIENCES Published by Belaruskaya Navuka Publishing House, Minsk, Republic of Belarus |
Summary: Gauss-type quadrature formulas for rational functions on real axis has been investigated.
Zabrejko P. P., Shevelevich K. V.
Estimates of the spectral radius for nonnegative matrices. pp. 11--15
Summary: The article deals with bounds of the spectral radius for nonnegative matrices. In particular, the analogues of the theorems, known early only for nondecomposable matrices, are stated for any nonnegative, even decomposable, matrices. Also, the statements concerning with nonnegative eigenvector corresponding to the spectral radius and having the maximal number of non-zero coordinates are presented.
Barabanov E. A., Fominykh E. I.
Singular exponents of linear differential system and exponents of its solutions. pp. 16--22
Summary: The typical properties of singular exponents of the linear differential systems and its Lyapunov and Perron exponents axe considered. The description of singular exponents of the linear differential systems and its Lyapunov and Perron exponents of two-dimensional system is given.
Demenchuk A. K.
On irregular forced almost periodic solutions to linear systems in critical nonresonance case. pp. 23--27
Summary: Let x = A(t)x + j(t) be an almost periodic differential system and mod (A) Ç mod (j) = {0}. The existence conditions for irregular forced almost periodic solutions of such systems are obtained in nonresonance critical case.
Marzan S. A.
An approximate solution of the Cauchy problem with Caputo fractional derivative of order. pp. 28--34
Summary: It is investigated the Cauchy problem for the nonlinear differential equation with the Caputo fractional derivative in the space of continuous functions on a finite interval of the real line. An approximate method of an average functional corrections is applied to an approximate solution of the problem considered. Numerical examples are given.
Yadchenko A. A.
On normal Hall subgroups of Ï-separable linear groups. pp. 35--39
Summary: Finite Ï-separable complex linear groups are considered. Certain sufficient conditions under which Hall Ï-subgroups of these groups are normal and Abelian, are found. The results obtained yield a solution of a well known Isaacs problem in some particular cases.
Kamornikov S. F., Kuzmenkova I. A.
Idempotents of the semigroup of all formations and regular transitive semigroup functors. pp. 40--44
Summary: Functor characterization of S-closed and Sn-closed idempotents of the semigroup of all formations is given.
Baranovskaya T. A.
On building of solutions to inhomogeneous power-type boundary value problem in special classes of functions. pp. 45--49
Summary: It is considered a possibility to construct a single-valued solution with finite number of zeroes in corresponding domains to the inhomogeneous power-type boundary value problem. Sufficient conditions of single-valuedness of solutions in particular cases are found.
Zhuk E. E., Serikova E. V.
Stepwise discriminant analysis in the space of principal components. pp. 50--55
Summary: The problem of discriminant analysis of multivariate Gaussian observations in the space of principal components is considered. The stepwise discriminant analysis procedure based on the dynamics of the interclass distances in the space of principal components is proposed and its efficiency is experimentally investigated.
Mukha V. S.
Differentiation of functions of symmetrical multidimensional matrices. pp. 56--61
Summary: Techniques for matrix differentiation in the case where the variable is symmetric multidimensional matrix is developed.
Summary: Formula for the carrier mobility in semiconductors is obtained on a basis of nonasymptotic expression for the transport cross section conditioned by Coulomb scattering of the carriers at the charged impurities. Comparison of the nonasymptotic analysis with the model of Conwell -- Weisskopf is carried out. It is shown that dependence of the mobility on some semiconductor parameters can be essentially differed for both cases.
Gorbatsievich A. K., Fatma Desokey
Construction of exact axisymmetric static vacuum solutions in the 5-dimensional Projective Unified Field Theory. pp. 67--70
Summary: In the framework of the 5-dimensional Projective Unified Field Theory (PUFT) in which gravitation is described by both space-time curvature and some hypothetical scalar field, we modify a method for construction of exact axisymmetric static vacuum solutions which was developed for General Relativity by Jordan, Ehlers, and Kundt. It is shown that the search of the axisymmetric static vacuum solutions of the PUFT's nonlinear field equations is reduced to the solving of the well familiar 2-dimensional Laplace's equation.
Blinkouski A. A.
Homogeneous isotropic cosmological models with stiff matter in the five-dimensional Projective Unified Field Theory. pp. 71--77
Summary: A homogeneous isotropic model of the Universe with stiff matter is considered in the framework of the five-dimensional Projective Unified Field Theory in which gravitation is described by both space-time curvature and some hypothetical scalar field. New exact solutions are found and analysed. It is shown that the model above mentioned admits solutions with Friedmann asymptotics.
Korshunov F. P., Zdanovich N. E., Marchenko I. G.
Electron irradiation influence on reverce-biased n-Si p-n-structures. pp. 78--82
Summary: The investigation of electron irradiation (4 MeV at 77 K) influence on electro-physical parameters of silicon p-n-structures have been carried. Sample irradiation was made with average electron beam intensity 2.1012 cm-2 • s-1 in two modes of operation: active -- at bias voltage 100 V, inducing electric field strength 104 ¸ 105 V/cm, and passive (without bias). It is established that at the same forward current the voltage drop is 1.6--1.8 larger in samples irradiated in passive mode though non-equilibrium charge carriers (holes) lifetime was equal for both modes of irradiation. The assumption was made that observed differences in parameters changes depending on irradiation mode are associated with electric field influence on distribution of main radiation centers in depth of structure base region.
Kovalev A. A., Zhvavyi S. P., Zhukov G. L.
Simulation of melting and solidification processes induced in cadmium telluride by pulsed laser irradiation. pp. 83--87
Summary: The calculated temperature dependence of thermal conductivity was used in computer simulation of phase transitions induced by laser irradiation (l = 694 nm, t = 80ns) in CdTe wafers. Results obtained from the numerical solution are in a reasonable agreement with experimental data.
Serhiyenya S. A., Pilipovich V. A., Zalesski V. B.
A calculation of solar cell parameters by its volt-ampere characteristic. pp. 88--93
Summary: Calculation methods of main parameters of solar cells are investigated. For increasing a calculation accuracy the least squares method is used. Various fitting strategies are analysed. The fitting strategy with different weights for minimizing of the sum of weight squares is proposed.
Brinkevich D. I., Prosolovich V. S.
The quenched-in defects in silicon doped with III goup impurities. pp. 94--97
Summary: The quenched-in defects introduction and annealing processes were studied in monocrystal silicon by Hall effect and IR absorption methods. Ga and In doping increase the concentration of quenched-in defects. Maximal efficiency of quenched-in defects generation in Si:Al was observed at 1100 °C. Doping with isovalent Sn-impurity leads to increasing of quenched-in defects concentration and displace annealing temperature in high-temperature
Summary: An approach for vectorization and intellectual extraction of line objects is proposed which works with color cartographic images. As well approach can be applied to process other types of color images (CAD\CAM engineering drawings, schematic plots, charts and etc.) It consists of four main stages: homogeneity region creation, local thinning, connected path search and automatic vectorization. The proposed approach doesn't intend to complete automatic vectorization and recognition replacement. But it's extremely useful and essential as an important addition to existent automatic algorithms and it allows to edit and to digitize the most difficult image areas.
Agievich S. V., Afonenko A. A.
On the properties of exponential substitutions. pp. 106--112
Summary: Exponentiation in the field of characteristic 2 is proposed to construct substitutions for cryptographic needs. Some properties of these substitutions that are related to differential and linear cryptanalysis methods are obtained.
Reznik I. A., Sadykhov R. Kh.
The modified algorithm for transfer and processing of the hidden images. pp. 113--120
Summary: In the given work the system of the hidden transfer of the information is considered. The algorithm of hiding binary and half-tone images in grayscale pictures is offered. The steganografic system is based on model of the two-dimensional spatial correlator. As filter function of the given correlator the secret key is used. The problems of efficiency, robustness, accuracy and performance of the suggested method are considered.
Dichkovskaya S. A.
Research of one of approximate algorithm of the solution of the multicriteria three-index axial decision problem. pp. 121--122
Kazakevich L. A.
Effect of internal elastic stress fields on defect formation in silicon. p. 122
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