Vol 17, No 8 (2011)

Articles

N-ORDER MOMENT FUNCTION FOR THE SOLUTION OF THE CAUCHY PROBLEM FOR DIFFUSION EQUATION WITH RANDOM COEFFICIENTS

Besedina T.

Abstract

Formula for n-order moment function for the solution of the Cauchy problem for three-dimensional diffusion equation with random coefficients and random initial condition is derived.
Vestnik of Samara University. Natural Science Series. 2011;17(8):5-20
pages 5-20 views

SMOOTH APPROXIMATION FOR THE SOLUTIONS OF ELLIPTIC SYSTEMS

Boluchevskaya A.

Abstract

The paper is devoted to the problem of piecewise-linear approximation of mapping for the elliptic system of solutions defined on triangular grids. A mapping is build to approximate the differential, and the estimate of error of approximation that does not depend on the degree of degeneracy of triangles of the grid. An analogous estimate is obtained for mappings which approximate the differential of solution of Beltrami equation.
Vestnik of Samara University. Natural Science Series. 2011;17(8):21-28
pages 21-28 views

A MIXED PROBLEM WITH INTEGRAL CONDITION FOR A DEGENERATIVE EQUATION OF THE HYPERBOLIC TYPE

Kirichenko S.

Abstract

In this article, the mixed problem for the hyperbolic degenerate equation with an integral condition is considered. The existence and uniqueness of a generalized solution are proved.
Vestnik of Samara University. Natural Science Series. 2011;17(8):29-36
pages 29-36 views

THE SYSTEM OF SHIFTS OF FUNCTIONS

Klimova E.

Abstract

The system of shift of functions  in L2 (R) space is considered in this paper. We find conditions on real sequence g(x), which provide such properties of the system as to be a frame, Bessel system, complete sequence in the space L2 (R).

Vestnik of Samara University. Natural Science Series. 2011;17(8):37-44
pages 37-44 views

NUMERICAL METHOD OF AN EVALUATION OF LIMITS OF MAXIMAL MEANS FOR PERIODIC FUNCTIONS

Lepilov A.

Abstract

The method of approximate calculation of limit of maximal mean for periodic function depending on the time and basic variables and differential inclusion with a constant right hand is offered.
Vestnik of Samara University. Natural Science Series. 2011;17(8):45-49
pages 45-49 views

FOURIER VECTOR TRANSFORMATION WITH DISCONTINUOUS COEFFICIENTS IN THE THEORY OF ELASTICITY

Malyshev A., Jaremko O.

Abstract

The article deals with the description of the method of Fourier vector transformation with discontinuous coefficients. The dynamics of the theory of elasticity illustrates the technique of method in solving problems of mathematical physics of heterogeneous media.
Vestnik of Samara University. Natural Science Series. 2011;17(8):50-58
pages 50-58 views

L-STABLE (4,2)-METHOD OF THE FOURTH ORDER FOR SOLVING STIFF PROBLEMS

Novikov E.

Abstract

(M,k)-methods for solving stiff problems, in which on each step two times the right-hand side of the system of differential equations is calculated are investigated. It is shown that the maximum order of accuracy of the L-stable (m,2)-method is equal to four. (4,2)-method of maximal order is built.
Vestnik of Samara University. Natural Science Series. 2011;17(8):59-68
pages 59-68 views

LIMIT THEOREM FOR INDEPENDENCE TRANSFORMATIONS COPULAS OF STUDENT'S t-DISTRIBUTION

Savinov E.

Abstract

In the paper we study copulas obtained as a result of independence transformation of random vectors with Student's t-distribution. For the triangular scheme of dependent r.v. connected by such IT-copulas central limit theorem is proved. In addition, it is shown that two-dimensional IT-copula of Cauchy distribution is not associated.
Vestnik of Samara University. Natural Science Series. 2011;17(8):69-85
pages 69-85 views

LOCAL SOLVABILITY OF SOME PROBLEM WITH FREE BORDER

Selivanova N., Shamolin M.

Abstract

A certain single-phase problem with free border is studied. The local solvability of such problem is proved. The more general method investigated earlier is used in concrete event in this work.
Vestnik of Samara University. Natural Science Series. 2011;17(8):86-94
pages 86-94 views

INITIAL-BOUNDARY VALUE PROBLEM FOR ONE-DIMENSION HYPERBOLIC EQUATION WITH INTEGRAL BOUNDARY CONDITION

Strigun M.

Abstract

In this paper, we study an initial-boundary value problem with nonlocal integral condition for a hyperbolic equation. The existence and uniqueness of a generalized solution of the problem is proved.
Vestnik of Samara University. Natural Science Series. 2011;17(8):95-101
pages 95-101 views

A PROBLEM WITH DISPLACEMENTS IN THE BOUNDARY CONDITIONS

Utkina E.

Abstract

A problem with conditions relating to the values of an unknown function on the opposite sides of a rectangular characteristiс domain D for a linear hyperbolic equations is considered. This problem is reduced to the system of Fredholm equations of the second kind. The proof of solvability is based on the a priori estimates of additional conditions on the coefficients of the equation.
Vestnik of Samara University. Natural Science Series. 2011;17(8):102-107
pages 102-107 views

NONLOCAL PROBLEMS FOR THE EQUATION OF THE MIXED PARABOLIC-HYPERBOLIC TYPE

Yunusova G.

Abstract

Boundary value problems with non-local conditions for partial differential equation are considered. In these problems, non-local conditions connect the values of a required solutions on the opposite sides of a rectangular domain. Criteria of uniqueness of each of the problems are obtained. Solutions to both problems are constructed as sums of Fourier series. The stability of solutions is proved.
Vestnik of Samara University. Natural Science Series. 2011;17(8):108-117
pages 108-117 views

MODELING OF DOUBLY PERIODIC SYSTEM OF PRODUCING WELLS. 2. PRODUCTIVITY INDEX

Astafiev V., Roters P.

Abstract

The question of productivity of doubly periodic systems of production wells is considered. Using the idealized production regime with a constant flow rate the analytical representation for the productivity index (PI) of the well was obtained and values depending on the drainage shapes were analyzed. Also an analytic representation for the Dietz's shape factor, which agrees with numerical calculations by the method of imaginary producing wells was obtained.
Vestnik of Samara University. Natural Science Series. 2011;17(8):118-127
pages 118-127 views

A RECTANGULAR PLATE ON A TWO-PARAMETER ELASTIC BASE: THE ANALYTICAL SOLUTION

Bolshakov A.

Abstract

In the paper the approximate solution for a problem of a rectangular plate on a two-parameter elastic base is suggested. The double series of beam functions satisfying elastic support boundary conditions are constructed. The analytical expressions for series function coefficients are obtained.
Vestnik of Samara University. Natural Science Series. 2011;17(8):128-133
pages 128-133 views

FILM EVAPORATION FLOWING ON THE WALL OF THE VERTICAL PLANE CHANNEL

Kluev N., Muryskin A., Mingulov K.

Abstract

This paper presents a mathematical model of a film evaporation of a liquid flowing downward by gravity on the wall of the vertical plane channel.
Vestnik of Samara University. Natural Science Series. 2011;17(8):134-141
pages 134-141 views

THE COMPELLED AXISYMMETRIC BENDING FLUCTUATIONS OF THICK ROUND RIGID PLATE

Shlyakhin D.

Abstract

The new closed solution of axially symmetric nonstationary problem of the theory of elasticity for thick round anisotropic plate with rigid of its external radial surface is constructed. Calculated relations are obtained by method of expansion in eigen vector-functions in the form of structural algorithm of finite transformations. Numerical results allow to define the natural-vibration frequency, and also the stress-strain state of the testing element.
Vestnik of Samara University. Natural Science Series. 2011;17(8):142-152
pages 142-152 views

THE INFLUENCE OF DIPOLE-DIPOLE INTERACTION ON THE ENTANGLEMENT FOR MANY-PHOTON TAVIS — CUMMINGS MODEL

Bashkirov E., Mastygin M.

Abstract

The influence of dipole-dipole interaction on the entanglement between two atoms and field in many-photon Tavis — Cummings with coherent cavity mode has been investigated. The results show that in the case of one-photon model the dipole-dipole interaction leads to the stabilization of atom-field entanglement.
Vestnik of Samara University. Natural Science Series. 2011;17(8):153-156
pages 153-156 views

DENS-PHORESIS — A RATIONAL WAY OF USING MEDICAL MUD IN THE TREATMENT OF OSTEOARTHRITIS OF THE KNEE JOINT

Vorobyev D., Garshina E., Zeleva O., Potapova I., Machenko Z., Raducrieva E., Burova E., Isxakova G.

Abstract

A new method of administering pharmaceutical substances with the help of apparatuses for dynamic electroneurostimulation (DENS) was suggested. This method is available in home conditions, preventoriums, social centers for communication and health. The article sets forth the results of experimental works on electrophoresis of medical mud with the help of the DENS apparatuses in patient with deforming osteoarthritis of the knee joint. The possibility of effective reduction of pain syndrome intensity in patients with osteoarthritis of II-III degrees was shown.
Vestnik of Samara University. Natural Science Series. 2011;17(8):157-162
pages 157-162 views

METHODS OF OBTAINING STRONTIUM AZIDE

Mokrov A., Kukushkin I.

Abstract

In this paper all the ordinary ways of obtaining strontium azide are discussed. A new and more appropriate method of obtaining strontium azide from sodium azide is introduced. The most effective conditions of this method are described.
Vestnik of Samara University. Natural Science Series. 2011;17(8):163-166
pages 163-166 views

PHARMACOLOGICAL ACTIVITY OF A PYRIMIDINE DERIVATIVES

Osipov A., Purygin P., Dubishchev A., Osipova A.

Abstract

The main directions of the search of biologically active compounds, pyrimi-dine derivatives are described.The synthesis of pyrimidines with anticancer, antimicrobial, antiviral activity is shown as the most frequent in recent years. The examples of compounds are given, which are already being used in medicine practice or may be good starting points for obtaining new drugs.
Vestnik of Samara University. Natural Science Series. 2011;17(8):167-172
pages 167-172 views

HEAVY METALS IN SOIL COVER OF ULIANOVSK CITY CHILDREN PARK

Efremova O., Prokopenko I., Prokhorova N.

Abstract

The features of heavy metals content and lateral distribution of heavy metals in soil cover of Ulianovsk city children park are described in the article. The possible sources of polymetallic territory pollution are discussed.
Vestnik of Samara University. Natural Science Series. 2011;17(8):173-178
pages 173-178 views

INFLUENCE OF DEFICIENCY OF CALCIUM AND MAGNESIUM ON MAINTENANCE OF PEPTIDE CONNECTIONS IN HUMAN ERYTHROCYTES AT THE INCUBATION IN VITRO

Isaeva A., Klenov R., Klenova N.

Abstract

The maintenance of peptide connections inside red blood cells and in the incubatory environment in the conditions of presence and absence of ions of calcium and magnesium, action of 1,3-dimetilksantin and АТГ is studied. The increase in the maintenance of peptides inside erythrocytes in the conditions of blocking L-calcium of channels and АТГ and reduction of their maintenance in the incubatory environment which is not containing ions of calcium is revealed.
Vestnik of Samara University. Natural Science Series. 2011;17(8):179-182
pages 179-182 views

SOME MATERIALS ABOUT FEATURES OF STRUCTURE OF BIOLOGICAL GROUPS OF PLANTS IN THE AFFORESTATIONS SERVING AS HABITATS OF CONVALLARIA MAJALIS L

Matveev N., Katsovets E., Korchikov E.

Abstract

The floristic structure of the investigated afforestations with participation of Convallaria majalis L. is considered. The rare species of plants growing together with Convallaria majalis L. are established. Potential stocks of medicinal raw materials of cenopopulations of Convallaria majalis L. in various afforestations are defined.
Vestnik of Samara University. Natural Science Series. 2011;17(8):183-195
pages 183-195 views

ANATOMO-HISTOLOGICAL RESEARCH OF LEAFLETS OF DIFFICULT SHEET HEDYSARUM GRANDIFLORUM PALL

Popova I., Plaksina T., Ryzhov Y., Tarasenko L.

Abstract

There were studied microscopical constitution features of the compound leaf leaflets of a large-flowered tick trefoil Hedysarum grandiflorum Pall. that was gathered in Kinel district of the Samara region, in 2,5 km to the south - east from the village of Preobrazhenka, in June, 2009. The result of the survey helped to confirm, specify and enlarge information about morphological and histological characteristics of the leaflet of a compound leaf one of the genus Hedysarum family.
Vestnik of Samara University. Natural Science Series. 2011;17(8):196-201
pages 196-201 views

LIVER FAT DYNAMICS OF AMUR SLEEPER PERCCOTTUS GLENII DYBOWSKI, 1877

Shemonaev E., Kirilenko E.

Abstract

According to the materials received in 2007 and 2009 years, the data on liver fat reserve dynamics of Amur sleeper in concordance with their age, sex and maturity stage throughout the vegetation period is given.
Vestnik of Samara University. Natural Science Series. 2011;17(8):202-205
pages 202-205 views

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies