Известия Нац. академии наук Беларуси. Сер. физ.-матем. наук, 1999, No.4
/ Издания академии / Научные журналы
Известия Нац. академии наук Беларуси. Сер. физ.-матем. наук, 1999, No.4
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Известия Национальной академии наук Беларуси
СЕРИЯ ФИЗИКО-МАТЕМАТИЧЕСКИХ НАУКИздатель: Институт математики НАН Беларуси, Минск, Республика Беларусь |
Номер 4, 1999
СОДЕРЖАНИЕ
МАТЕМАТИКА
Trubnikov Yu. V.
On some method of finding of Chebyshev iterative parameters. pp. 5--9
Summary: The paper is devoted to the proof of a convergence of iterative processes based on polynomials of least deviation.
Manyuk E.M., Yanovich L.A.
On formulae of linear and quadratic interpolation of functionals in the space of differentiable functions. pp. 10--15
Summary: Linear and quadratic interpolation formulas for functionals in the space of differentiable functions are constructed.
Tsekhan O.B.
Parameter identifiability of linear time-varying singularly perturbed systems with delay. pp. 16--22
Summary: A problem of parameter identifiability of linear time-varying singularly perturbed systems with delay is considered. The necessary, sufficient algebraic conditions of identifiability have been proved. They are expressed by means of the system determining equations solutions.
Lipnitsky A.A.
Elliptic curves with bad additive reduction defined over real formal power series and their Brauer groups. pp. 23--27
Summary: The complete description of Brauer groups of elliptic curves with bad additive reduction defined over real formal power series is obtained.
Vasil'ev D.V.
On an analogue of Schmidt's theorem for curves in the space C3. pp. 28--32
Summary: An extremality of general type curves in C3 is proven.
Troush N.N., Markovskaya N.V.
Investigation of the estimate of mutual covariance function. pp. 33--38
Summary: The estimation of mutual covariance function of stationary stochastic process with discrete time is constructed. Moments of this estimation are found, their asymptotic behaviour and limit distribution of the estimation are investigated.
Metelskii N.N., Naidenko V.G.
Partially convex hull in space Rn. pp. 39--42
Summary: It is shown to be a NP-hard problem to decide whether a given point of Rn is contained in the partially convex hull of a given finite point set.
Gaishun L.N., Goryachkin V.V., Krahotko V.V.
The problem of the minimal realization of discrete 2D-systems. pp. 43--48
Summary: The method of construction of a minimal realization for discrete 2D-system is proposed.
Dolgopolova O.B., Zverovich B.I., Shtin S.L.
About the possibility of an explicit solution of the Riemann's matrix problem. pp. 49--52
Summary: We develop some tool for the solution of Riemanns problem by means of construction an analog of Cauchy kernel on a given Riemann surface.
Blinova E.I., Zalesky B.A.
Properties of the clusters that arise in maximum a posteriori estimates in Ising models. pp. 53--58
Summary: In this paper, for binary images degraded with independent Bernoullian noise, we study the maximum a posteriori (MAP) estimates properties in the case of the well-known Ising model prior distribution.MAP estimates of the black image with great probability do not contain large clusters of white points.
ФИЗИКА
Sirota N.N.
The influence of energy excitation on the physical-chemical properties of the Debye solids. pp. 59--63
Summary: The variation of thermodynamical properties as the thermal expansion coefficients, the temperature coefficients of thermal conductivity, conductivity, self-diffusion coefficients connected with harmonic and anharmonic atomic mean-square displacements as function of variation of characteristic temperature as a measure of energy excitation of solids with the Debye phonon spectra (the Debye solids) are qualitatively analyzed.
Sirota N.N., Sirota I.M.
The values and temperature dependence of Debye integrals and functions. pp. 64--66
Summary: The new forms of essential Debye integrals which are used for calculating of thermodynamical and some physical properties of Debye solids are considered.Tabulated values of Debye integrals and functions with respect to temperature X = Q/T are given.
Otchik V.S.
On the connection between spherical and parabolic bases in the quantum mechanical Kepler problem in the Lobachevsky space. pp. 67--72
Summary: The relations between solutions of the Schrodinger equation with the Coulomb potential in two coordinate systems of the Lobachevsky space are studied. An explicit form of coefficients is found in the expansion of separated solutions in the parabolic coordinate system in terms of separated solutions in the spherical one.
Kapshai V.N., Fursin A.I.
Consequences of the system of field and gauge equations in non-abelian case in the Lorentz gauge. pp. 73--76
Summary: An equation is obtained as a consequence of the system of gauge and field equations in non-abelian case. All these equations are checked in bottom orders with the help of generating functionals calculated in the raw according to perturbation theory. All calculations are made in Lorentz gauge.
Pilipovich V.A., Esman A.K., Goncharenko I.A., Posedko V.S., Solonovich I.F.
Multiparameter coding in optical fibre digital information transmission systems. pp. 77--81
Summary: The use of multiparameter coding of optical signals for increasing the information capacity of digital optical fibre communication systems is proposed.
Time delay during the propagation of optical signals coded on different parameters is estimated. It is shown, that the variations of the delay of the pulses propagating on different carrier frequencies and the ones for the pulses with different polarisations are the values of the same order. That gives the possibility of their mutual compensation.
Voytenko I.G., Kulak G.V., Kulak V.I., Ropot P.I.
Efficiency of the acoustooptic interactions by the flexural ultrasonic waves in singe-mode fibers with birefringence. pp. 82--86
Summary: Specific features of the acoustooptic interaction by the flexural ultrasonic waves in single-mode fiber with birefringence are investigated for pulsed and continuous diffraction regimes. It is shown that under enhensing the pulse width the diffraction efficiency may be decreased. The new scheme of acoustooptical interaction in fiber-optic waveguides is carried out on the bases of which the diffraction efficiency may be only less then one hundred percent. It is shown that light pulse evelope of diffracted wave significantly changed to incidence light pulse evelope (gaussian), when time group duration of diffracted wave bigger then that of incidence pulse.
Korshunov F. P., Kurilovich N. F., Prokhorenko T. A., Troshchinskii V. T., Shesholko V. K.
The influence of electron irradiation at the various temperatures and annealing on carriers mobility at the low temperatures in neutron transmutation doped gallium arsenide. pp. 87--90
Summary: The influence of electron irradiation at the various temperatures and annealing on measured at T = 100 K carriers mobility in neutron transmutation doped GaAs have been investigated. It was detected that rate of mobility decreasing with irradiation dose increasing decreases when irradiation temperature increases. It was shown that at the same time it take place the radiation defects creating and their particular or full annealing (in the dependence on irradiation temperature). Radiation-stimulated annealing (annealing that take place during irradiation at the elevated temperatures) is more effective than the annealing at the same temperatures that take place after crystals are irradiated at room temperature. It means that any defects annealing during irradiation at elevated temperatures take place at more low temperatures than that during annealing after irradiation at room temperature.
Orlova N.S., Andreeva O.E., Pushkarev A.V., Yakimovich V.N., Orlik L .K.
X-ray study of character of elastic anisotropy in the AgGaSe2 compound. pp. 91--97
Summary: The investigations on the anisotropy of the elastic properties of the AgGaSe2 ternary compound with the chalcopyrite-type tetragonal structure were performed by the method of X-ray thermal diffuse scattering as well as by a X-ray powder difiractometry technique under high pressure. The mean-square atomic displacements of the Ag, Ga, Se and S ions in lattice of AgGaSe2 and AgGaS2 were also determined from X-ray powder diffraction data, measured at different temperatures. The comparative analysis of the character of the elastic anisotropy for the ternary compounds AgGaSe2 and AgGaS2 with the chalcopyrite structure and the binary analogs ZnSe, CdSe and ZnS, CdS with the sphalerite structure was carried out.
Novysh B.V., Dorozhkin N.N.
Interpolation scheme for calculation of electron-phonon matrix elements. pp. 98--101
Summary: Calculation scheme to assess electron-phonon matrix elements is presented using their expansion into angular components. The scheme may be used in the framework of various methods utilizing first-principle calculation of EP matrix elements, e.g. frozen-phonon approximation, where the direct calculation is very difficult and time-consuming.
Petrashko V.V., Semenenko Yu.A., Prytkova N.A., Novysh B.V., Yarunichev V.P.
Synthesis and investigations of properties of (Bi,Pb) -- (Sr,K) -- (Ca,K) -- Cu -- (O,F) superconductors. pp. 102--106
Summary: We investigate the influence of F and K as well as time and temperature of synthesis on phase composition and superconducting properties of (Bi,Pb) -- Sr -- Ca -- Cu --O system. These partial substitutions were shown to increase the output of 2223 phase. Critical temperature is more sensitive to synthesis conditions than to volume content of 2223 phase.
Loginov V.F., Kuznetsov G.P., Mikutsky V.S.
Numarical modelling of a daily course of the meteorological parameters. pp. 107--111
Summary: The mathematical simulation of daily change of vertical structures of wind speed, temperature and moisture is considered. Unlike before used ways of the closing of system of hydrothermodynamics equations the two-parametrical method of closing of system of atmosphere non-stationary boundary layer equations is applied. The heat balance of underlying surface equation is used to take into account its influence. The computing experiment shows a considerable influence of underlying surface conditions on meteofield values. So, calculated temperature in a city is higher than in agricultural district, maximal difference of these temperatures is reached at night time.
Homyakov P.A.
Perturbation theory for the one-dimensional optical polaron. pp. 112--114
Summary: The ground energy of the one-dimensional optical polaron was calculated by the perturbation theory method using a special diagrammatic technique in the forth oder in coupling constant a. It was pointed to a possibility of the phase-like transition analysis in this polaron system.
ИНФОРМАТИКА
Gagarin A.V.
Chordal (1,b)-polar graphs. pp. 115--118
Summary: A class of (a,b)-polar graphs is hereditary and can be characterized in terms of forbidden induced subgraphs. We give the finite list of forbidden induced subgraphs for chordal (l, b)-polar graphs. Minimal forbidden induced subgraphs for (l, ¥)-polar graphs are shown. Also we conjecture here the finiteness of such a list for (l,b)-polar graphs in the general case.
Emelichev V.A., Berdysheva R.A.
On measure of stability in the vector integer programming problem of a lexicographic optimization. pp. 119--124
Summary: Lower and upper bounds of stability radius and formula for the quasistability radius of a lexicographic set in the vector linear integer programming problem have been found.
Guschinsky N. N., Levin G.M.
Models and methods to optimize a structure and parameters of multiposition machining. pp. 125--131
Summary: Mathematical models and methods for automation of designing manufacturing process for machining on automatic transfer lines are considered. The following parameters of the designed process are determined: number of workstations, assigning of the given set of manufacturing steps to the workstations; orientation of the part, number of positions and cutting conditions for each workstation. To solve the obtained optimization problem the special multilevel decomposition scheme is proposed. It based on the decomposition approaches in combination with methods of nonlinear and discrete programming.
Zverovich I.B.
Strong hereditariness of graphical sequences and hereditary classes of intersection graphs. pp. 132--137
Summary: A general model of hereditary systems is considered. It is applied to the set Õ of all graphical sequences with the following partial order £ : p £ s if and only if a has a realization which contains a realization of p as a subgraph (not necessary induced). For the hereditary system (Õ, £) a variant of Rao's conjecture is proved: every hereditary subclass in (Õ, £) has a finite characterization in terms of forbidden graphical sequences. This result can be applied to characterization of forcibly P-graphic degree sequences.
A method for characterization of hereditary subclasses of intersection graphs is worked out.
АННОТАЦИИ ДЕПОНИРОВАННЫХ СТАТЕЙ
Stalevskaya S.N.
Robust version of "approximating" approach in parameter estimation for econometric simultaneous equations models. p. 138
Krushevsky A.E., Kondratyuk V.F.
About a linear dependence of the variational equations at the solution of boundary value problems of a theory of elastic strength. p. 138
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Разработана и поддерживается Николаем Н. Костюковичем. Последнее обновление: 2 декабря 2006 г.
Создана при участии Игнатия И. Корсака
Копирайт © 2000-2006 Национальная академии наук Беларуси
Копирайт © 1999 Издательство "Беларуская навука"
